mm/page_alloc: remove realsize in free_area_init_core()
[linux-block.git] / arch / x86 / Kconfig
CommitLineData
b2441318 1# SPDX-License-Identifier: GPL-2.0
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SR
2# Select 32 or 64 bit
3config 64BIT
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MY
4 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
8f9ca475 6 ---help---
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SR
7 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
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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
f616ab59 31 select NEED_DMA_MAP_STATE
09230cbc 32 select SWIOTLB
d94e0685 33 select X86_DEV_DMA_OPS
f8781c4a 34 select ARCH_HAS_SYSCALL_WRAPPER
1032c0ba 35
d94e0685
IM
36#
37# Arch settings
38#
39# ( Note that options that are marked 'if X86_64' could in principle be
40# ported to 32-bit as well. )
41#
8d5fffb9 42config X86
3c2362e6 43 def_bool y
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IM
44 #
45 # Note: keep this list sorted alphabetically
46 #
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IM
47 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
48 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
49 select ANON_INODES
50 select ARCH_CLOCKSOURCE_DATA
51 select ARCH_DISCARD_MEMBLOCK
c763ea26 52 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
fa5b6ec9 53 select ARCH_HAS_DEBUG_VIRTUAL
21266be9 54 select ARCH_HAS_DEVMEM_IS_ALLOWED
6471b825 55 select ARCH_HAS_ELF_RANDOMIZE
72d93104 56 select ARCH_HAS_FAST_MULTIPLIER
316d097c 57 select ARCH_HAS_FILTER_PGPROT
6974f0c4 58 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 59 select ARCH_HAS_GCOV_PROFILE_ALL
5c9a8750 60 select ARCH_HAS_KCOV if X86_64
10bcc80e 61 select ARCH_HAS_MEMBARRIER_SYNC_CORE
c763ea26 62 select ARCH_HAS_PMEM_API if X86_64
39208aa7 63 select ARCH_HAS_REFCOUNT
0aed55af 64 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
8780356e 65 select ARCH_HAS_UACCESS_MCSAFE if X86_64
d2852a22 66 select ARCH_HAS_SET_MEMORY
6471b825 67 select ARCH_HAS_SG_CHAIN
ad21fc4f
LA
68 select ARCH_HAS_STRICT_KERNEL_RWX
69 select ARCH_HAS_STRICT_MODULE_RWX
ac1ab12a 70 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
c6d30853 71 select ARCH_HAS_UBSAN_SANITIZE_ALL
65f7d049 72 select ARCH_HAS_ZONE_DEVICE if X86_64
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IM
73 select ARCH_HAVE_NMI_SAFE_CMPXCHG
74 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
77fbbc81 75 select ARCH_MIGHT_HAVE_PC_PARPORT
5e2c18c0 76 select ARCH_MIGHT_HAVE_PC_SERIO
6471b825 77 select ARCH_SUPPORTS_ATOMIC_RMW
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IM
78 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
79 select ARCH_USE_BUILTIN_BSWAP
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IM
80 select ARCH_USE_QUEUED_RWLOCKS
81 select ARCH_USE_QUEUED_SPINLOCKS
ce4a4e56 82 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
c763ea26 83 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
38d8b4e6 84 select ARCH_WANTS_THP_SWAP if X86_64
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IM
85 select BUILDTIME_EXTABLE_SORT
86 select CLKEVT_I8253
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IM
87 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
88 select CLOCKSOURCE_WATCHDOG
6471b825 89 select DCACHE_WORD_ACCESS
fec777c3 90 select DMA_DIRECT_OPS
45471cd9
LT
91 select EDAC_ATOMIC_SCRUB
92 select EDAC_SUPPORT
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IM
93 select GENERIC_CLOCKEVENTS
94 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
95 select GENERIC_CLOCKEVENTS_MIN_ADJUST
96 select GENERIC_CMOS_UPDATE
97 select GENERIC_CPU_AUTOPROBE
61dc0f55 98 select GENERIC_CPU_VULNERABILITIES
5b7c73e0 99 select GENERIC_EARLY_IOREMAP
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IM
100 select GENERIC_FIND_FIRST_BIT
101 select GENERIC_IOMAP
c7d6c9dd 102 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
0fa115da 103 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
ad7a929f 104 select GENERIC_IRQ_MIGRATION if SMP
6471b825 105 select GENERIC_IRQ_PROBE
c201c917 106 select GENERIC_IRQ_RESERVATION_MODE
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IM
107 select GENERIC_IRQ_SHOW
108 select GENERIC_PENDING_IRQ if SMP
109 select GENERIC_SMP_IDLE_THREAD
110 select GENERIC_STRNCPY_FROM_USER
111 select GENERIC_STRNLEN_USER
112 select GENERIC_TIME_VSYSCALL
7edaeb68 113 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
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IM
114 select HAVE_ACPI_APEI if ACPI
115 select HAVE_ACPI_APEI_NMI if ACPI
116 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
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117 select HAVE_ARCH_AUDITSYSCALL
118 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
119 select HAVE_ARCH_JUMP_LABEL
d17a1d97 120 select HAVE_ARCH_KASAN if X86_64
6471b825 121 select HAVE_ARCH_KGDB
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DC
122 select HAVE_ARCH_MMAP_RND_BITS if MMU
123 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
1b028f78 124 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
6471b825 125 select HAVE_ARCH_SECCOMP_FILTER
f7d83c1c 126 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
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IM
127 select HAVE_ARCH_TRACEHOOK
128 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
a00cc7d9 129 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
e37e43a4 130 select HAVE_ARCH_VMAP_STACK if X86_64
c763ea26 131 select HAVE_ARCH_WITHIN_STACK_FRAMES
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IM
132 select HAVE_CC_STACKPROTECTOR
133 select HAVE_CMPXCHG_DOUBLE
134 select HAVE_CMPXCHG_LOCAL
135 select HAVE_CONTEXT_TRACKING if X86_64
c1bd55f9 136 select HAVE_COPY_THREAD_TLS
cf4db259 137 select HAVE_C_RECORDMCOUNT
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IM
138 select HAVE_DEBUG_KMEMLEAK
139 select HAVE_DEBUG_STACKOVERFLOW
6471b825 140 select HAVE_DMA_CONTIGUOUS
677aa9f7 141 select HAVE_DYNAMIC_FTRACE
06aeaaea 142 select HAVE_DYNAMIC_FTRACE_WITH_REGS
03f5781b 143 select HAVE_EBPF_JIT
58340a07 144 select HAVE_EFFICIENT_UNALIGNED_ACCESS
5f56a5df 145 select HAVE_EXIT_THREAD
644e0e8d 146 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
6471b825 147 select HAVE_FTRACE_MCOUNT_RECORD
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IM
148 select HAVE_FUNCTION_GRAPH_TRACER
149 select HAVE_FUNCTION_TRACER
6b90bd4b 150 select HAVE_GCC_PLUGINS
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IM
151 select HAVE_HW_BREAKPOINT
152 select HAVE_IDE
153 select HAVE_IOREMAP_PROT
154 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
155 select HAVE_IRQ_TIME_ACCOUNTING
2e9f3bdd 156 select HAVE_KERNEL_BZIP2
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IM
157 select HAVE_KERNEL_GZIP
158 select HAVE_KERNEL_LZ4
2e9f3bdd 159 select HAVE_KERNEL_LZMA
13510997 160 select HAVE_KERNEL_LZO
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IM
161 select HAVE_KERNEL_XZ
162 select HAVE_KPROBES
163 select HAVE_KPROBES_ON_FTRACE
540adea3 164 select HAVE_FUNCTION_ERROR_INJECTION
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IM
165 select HAVE_KRETPROBES
166 select HAVE_KVM
167 select HAVE_LIVEPATCH if X86_64
168 select HAVE_MEMBLOCK
169 select HAVE_MEMBLOCK_NODE_MAP
0102752e 170 select HAVE_MIXED_BREAKPOINTS_REGS
ee9f8fce 171 select HAVE_MOD_ARCH_SPECIFIC
42a0bb3f 172 select HAVE_NMI
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IM
173 select HAVE_OPROFILE
174 select HAVE_OPTPROBES
175 select HAVE_PCSPKR_PLATFORM
176 select HAVE_PERF_EVENTS
c01d4323 177 select HAVE_PERF_EVENTS_NMI
92e5aae4 178 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
c5e63197 179 select HAVE_PERF_REGS
c5ebcedb 180 select HAVE_PERF_USER_STACK_DUMP
9e52fc2b 181 select HAVE_RCU_TABLE_FREE
6471b825 182 select HAVE_REGS_AND_STACK_ACCESS_API
11af8474 183 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
c763ea26 184 select HAVE_STACK_VALIDATION if X86_64
6471b825 185 select HAVE_SYSCALL_TRACEPOINTS
6471b825 186 select HAVE_UNSTABLE_SCHED_CLOCK
7c68af6e 187 select HAVE_USER_RETURN_NOTIFIER
c0185808 188 select IRQ_FORCED_THREADING
86596f0a 189 select NEED_SG_DMA_LENGTH
df65c1bc 190 select PCI_LOCKLESS_CONFIG
6471b825 191 select PERF_EVENTS
3195ef59 192 select RTC_LIB
d6faca40 193 select RTC_MC146818_LIB
6471b825 194 select SPARSE_IRQ
83fe27ea 195 select SRCU
6471b825 196 select SYSCTL_EXCEPTION_TRACE
15f4eae7 197 select THREAD_INFO_IN_TASK
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IM
198 select USER_STACKTRACE_SUPPORT
199 select VIRT_TO_BUS
6471b825 200 select X86_FEATURE_NAMES if PROC_FS
7d8330a5 201
ba7e4d13 202config INSTRUCTION_DECODER
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JB
203 def_bool y
204 depends on KPROBES || PERF_EVENTS || UPROBES
ba7e4d13 205
51b26ada
LT
206config OUTPUT_FORMAT
207 string
208 default "elf32-i386" if X86_32
209 default "elf64-x86-64" if X86_64
210
73531905 211config ARCH_DEFCONFIG
b9b39bfb 212 string
73531905
SR
213 default "arch/x86/configs/i386_defconfig" if X86_32
214 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 215
8d5fffb9 216config LOCKDEP_SUPPORT
3c2362e6 217 def_bool y
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SR
218
219config STACKTRACE_SUPPORT
3c2362e6 220 def_bool y
8d5fffb9 221
8d5fffb9 222config MMU
3c2362e6 223 def_bool y
8d5fffb9 224
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DC
225config ARCH_MMAP_RND_BITS_MIN
226 default 28 if 64BIT
227 default 8
228
229config ARCH_MMAP_RND_BITS_MAX
230 default 32 if 64BIT
231 default 16
232
233config ARCH_MMAP_RND_COMPAT_BITS_MIN
234 default 8
235
236config ARCH_MMAP_RND_COMPAT_BITS_MAX
237 default 16
238
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SR
239config SBUS
240 bool
241
242config GENERIC_ISA_DMA
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JB
243 def_bool y
244 depends on ISA_DMA_API
8d5fffb9 245
8d5fffb9 246config GENERIC_BUG
3c2362e6 247 def_bool y
8d5fffb9 248 depends on BUG
b93a531e
JB
249 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
250
251config GENERIC_BUG_RELATIVE_POINTERS
252 bool
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SR
253
254config GENERIC_HWEIGHT
3c2362e6 255 def_bool y
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SR
256
257config ARCH_MAY_HAVE_PC_FDC
3120e25e
JB
258 def_bool y
259 depends on ISA_DMA_API
8d5fffb9 260
1032c0ba 261config RWSEM_XCHGADD_ALGORITHM
3120e25e 262 def_bool y
1032c0ba 263
1032c0ba
SR
264config GENERIC_CALIBRATE_DELAY
265 def_bool y
266
9a0b8415 267config ARCH_HAS_CPU_RELAX
268 def_bool y
269
1b27d05b
PE
270config ARCH_HAS_CACHE_LINE_SIZE
271 def_bool y
272
316d097c
DH
273config ARCH_HAS_FILTER_PGPROT
274 def_bool y
275
dd5af90a 276config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 277 def_bool y
b32ef636 278
08fc4580
TH
279config NEED_PER_CPU_EMBED_FIRST_CHUNK
280 def_bool y
281
282config NEED_PER_CPU_PAGE_FIRST_CHUNK
11124411
TH
283 def_bool y
284
801e4062
JB
285config ARCH_HIBERNATION_POSSIBLE
286 def_bool y
801e4062 287
f4cb5700
JB
288config ARCH_SUSPEND_POSSIBLE
289 def_bool y
f4cb5700 290
cfe28c5d
SC
291config ARCH_WANT_HUGE_PMD_SHARE
292 def_bool y
293
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SC
294config ARCH_WANT_GENERAL_HUGETLB
295 def_bool y
296
8d5fffb9 297config ZONE_DMA32
e0fd24a3 298 def_bool y if X86_64
8d5fffb9 299
8d5fffb9 300config AUDIT_ARCH
e0fd24a3 301 def_bool y if X86_64
8d5fffb9 302
765c68bd
IM
303config ARCH_SUPPORTS_OPTIMIZED_INLINING
304 def_bool y
305
6a11f75b
AM
306config ARCH_SUPPORTS_DEBUG_PAGEALLOC
307 def_bool y
308
d6f2d75a
AR
309config KASAN_SHADOW_OFFSET
310 hex
311 depends on KASAN
312 default 0xdffffc0000000000
313
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SW
314config HAVE_INTEL_TXT
315 def_bool y
6ea30386 316 depends on INTEL_IOMMU && ACPI
69575d38 317
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SR
318config X86_32_SMP
319 def_bool y
320 depends on X86_32 && SMP
321
322config X86_64_SMP
323 def_bool y
324 depends on X86_64 && SMP
325
ccbeed3a
TH
326config X86_32_LAZY_GS
327 def_bool y
2bc2f688 328 depends on X86_32 && CC_STACKPROTECTOR_NONE
ccbeed3a 329
2b144498
SD
330config ARCH_SUPPORTS_UPROBES
331 def_bool y
332
d20642f0
RH
333config FIX_EARLYCON_MEM
334 def_bool y
335
98233368
KS
336config PGTABLE_LEVELS
337 int
77ef56e4 338 default 5 if X86_5LEVEL
98233368
KS
339 default 4 if X86_64
340 default 3 if X86_PAE
341 default 2
342
506f1d07 343source "init/Kconfig"
dc52ddc0 344source "kernel/Kconfig.freezer"
8d5fffb9 345
506f1d07
SR
346menu "Processor type and features"
347
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RD
348config ZONE_DMA
349 bool "DMA memory allocation support" if EXPERT
350 default y
351 help
352 DMA memory allocation support allows devices with less than 32-bit
353 addressing to allocate within the first 16MB of address space.
354 Disable if no such devices will be used.
355
356 If unsure, say Y.
357
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SR
358config SMP
359 bool "Symmetric multi-processing support"
360 ---help---
361 This enables support for systems with more than one CPU. If you have
4a474157
RG
362 a system with only one CPU, say N. If you have a system with more
363 than one CPU, say Y.
506f1d07 364
4a474157 365 If you say N here, the kernel will run on uni- and multiprocessor
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SR
366 machines, but will use only one CPU of a multiprocessor machine. If
367 you say Y here, the kernel will run on many, but not all,
4a474157 368 uniprocessor machines. On a uniprocessor machine, the kernel
506f1d07
SR
369 will run faster if you say N here.
370
371 Note that if you say Y here and choose architecture "586" or
372 "Pentium" under "Processor family", the kernel will not work on 486
373 architectures. Similarly, multiprocessor kernels for the "PPro"
374 architecture may not work on all Pentium based boards.
375
376 People using multiprocessor machines who say Y here should also say
377 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
378 Management" code will be disabled if you say Y here.
379
395cf969 380 See also <file:Documentation/x86/i386/IO-APIC.txt>,
c9525a3f 381 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
506f1d07
SR
382 <http://www.tldp.org/docs.html#howto>.
383
384 If you don't know what to do here, say N.
385
9def39be
JT
386config X86_FEATURE_NAMES
387 bool "Processor feature human-readable names" if EMBEDDED
388 default y
389 ---help---
390 This option compiles in a table of x86 feature bits and corresponding
391 names. This is required to support /proc/cpuinfo and a few kernel
392 messages. You can disable this to save space, at the expense of
393 making those few kernel messages show numeric feature bits instead.
394
395 If in doubt, say Y.
396
06cd9a7d
YL
397config X86_X2APIC
398 bool "Support x2apic"
19e3d60d 399 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
06cd9a7d
YL
400 ---help---
401 This enables x2apic support on CPUs that have this feature.
402
403 This allows 32-bit apic IDs (so it can support very large systems),
404 and accesses the local apic via MSRs not via mmio.
405
06cd9a7d
YL
406 If you don't know what to do here, say N.
407
6695c85b 408config X86_MPPARSE
6e87f9b7 409 bool "Enable MPS table" if ACPI || SFI
7a527688 410 default y
5ab74722 411 depends on X86_LOCAL_APIC
8f9ca475 412 ---help---
6695c85b
YL
413 For old smp systems that do not have proper acpi support. Newer systems
414 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 415
ddd70cf9
JN
416config GOLDFISH
417 def_bool y
418 depends on X86_GOLDFISH
419
76b04384
DW
420config RETPOLINE
421 bool "Avoid speculative indirect branches in kernel"
422 default y
d5028ba8 423 select STACK_VALIDATION if HAVE_STACK_VALIDATION
76b04384
DW
424 help
425 Compile kernel with the retpoline compiler options to guard against
426 kernel-to-user data leaks by avoiding speculative indirect
427 branches. Requires a compiler with -mindirect-branch=thunk-extern
428 support for full protection. The kernel may run slower.
429
430 Without compiler support, at least indirect branches in assembler
431 code are eliminated. Since this includes the syscall entry path,
432 it is not entirely pointless.
433
f01d7d51
VS
434config INTEL_RDT
435 bool "Intel Resource Director Technology support"
78e99b4a
FY
436 default n
437 depends on X86 && CPU_SUP_INTEL
59fe5a77 438 select KERNFS
78e99b4a 439 help
f01d7d51
VS
440 Select to enable resource allocation and monitoring which are
441 sub-features of Intel Resource Director Technology(RDT). More
442 information about RDT can be found in the Intel x86
443 Architecture Software Developer Manual.
78e99b4a
FY
444
445 Say N if unsure.
446
8425091f 447if X86_32
a0d0bb4d
RD
448config X86_BIGSMP
449 bool "Support for big SMP systems with more than 8 CPUs"
450 depends on SMP
451 ---help---
452 This option is needed for the systems that have more than 8 CPUs
453
c5c606d9
RT
454config X86_EXTENDED_PLATFORM
455 bool "Support for extended (non-PC) x86 platforms"
456 default y
8f9ca475 457 ---help---
06ac8346
IM
458 If you disable this option then the kernel will only support
459 standard PC platforms. (which covers the vast majority of
460 systems out there.)
461
8425091f
RT
462 If you enable this option then you'll be able to select support
463 for the following (non-PC) 32 bit x86 platforms:
cb7b8023 464 Goldfish (Android emulator)
8425091f 465 AMD Elan
8425091f
RT
466 RDC R-321x SoC
467 SGI 320/540 (Visual Workstation)
83125a3a 468 STA2X11-based (e.g. Northville)
3f4110a4 469 Moorestown MID devices
06ac8346
IM
470
471 If you have one of these systems, or if you want to build a
472 generic distribution kernel, say Y here - otherwise say N.
8425091f 473endif
06ac8346 474
8425091f
RT
475if X86_64
476config X86_EXTENDED_PLATFORM
477 bool "Support for extended (non-PC) x86 platforms"
478 default y
479 ---help---
480 If you disable this option then the kernel will only support
481 standard PC platforms. (which covers the vast majority of
482 systems out there.)
483
484 If you enable this option then you'll be able to select support
485 for the following (non-PC) 64 bit x86 platforms:
44b111b5 486 Numascale NumaChip
8425091f
RT
487 ScaleMP vSMP
488 SGI Ultraviolet
489
490 If you have one of these systems, or if you want to build a
491 generic distribution kernel, say Y here - otherwise say N.
492endif
c5c606d9
RT
493# This is an alphabetically sorted list of 64 bit extended platforms
494# Please maintain the alphabetic order if and when there are additions
44b111b5
SP
495config X86_NUMACHIP
496 bool "Numascale NumaChip"
497 depends on X86_64
498 depends on X86_EXTENDED_PLATFORM
499 depends on NUMA
500 depends on SMP
501 depends on X86_X2APIC
f9726bfd 502 depends on PCI_MMCONFIG
44b111b5
SP
503 ---help---
504 Adds support for Numascale NumaChip large-SMP systems. Needed to
505 enable more than ~168 cores.
506 If you don't have one of these, you should say N here.
506f1d07 507
c5c606d9
RT
508config X86_VSMP
509 bool "ScaleMP vSMP"
6276a074 510 select HYPERVISOR_GUEST
c5c606d9
RT
511 select PARAVIRT
512 depends on X86_64 && PCI
513 depends on X86_EXTENDED_PLATFORM
ead91d4b 514 depends on SMP
8f9ca475 515 ---help---
c5c606d9
RT
516 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
517 supposed to run on these EM64T-based machines. Only choose this option
518 if you have one of these machines.
5e3a77e9 519
03b48632
NP
520config X86_UV
521 bool "SGI Ultraviolet"
522 depends on X86_64
c5c606d9 523 depends on X86_EXTENDED_PLATFORM
54c28d29 524 depends on NUMA
1ecb4ae5 525 depends on EFI
9d6c26e7 526 depends on X86_X2APIC
1222e564 527 depends on PCI
8f9ca475 528 ---help---
03b48632
NP
529 This option is needed in order to support SGI Ultraviolet systems.
530 If you don't have one of these, you should say N here.
531
c5c606d9
RT
532# Following is an alphabetically sorted list of 32 bit extended platforms
533# Please maintain the alphabetic order if and when there are additions
506f1d07 534
ddd70cf9
JN
535config X86_GOLDFISH
536 bool "Goldfish (Virtual Platform)"
cb7b8023 537 depends on X86_EXTENDED_PLATFORM
ddd70cf9
JN
538 ---help---
539 Enable support for the Goldfish virtual platform used primarily
540 for Android development. Unless you are building for the Android
541 Goldfish emulator say N here.
542
c751e17b
TG
543config X86_INTEL_CE
544 bool "CE4100 TV platform"
545 depends on PCI
546 depends on PCI_GODIRECT
6084a6e2 547 depends on X86_IO_APIC
c751e17b
TG
548 depends on X86_32
549 depends on X86_EXTENDED_PLATFORM
37bc9f50 550 select X86_REBOOTFIXUPS
da6b737b
SAS
551 select OF
552 select OF_EARLY_FLATTREE
c751e17b
TG
553 ---help---
554 Select for the Intel CE media processor (CE4100) SOC.
555 This option compiles in support for the CE4100 SOC for settop
556 boxes and media devices.
557
4cb9b00f 558config X86_INTEL_MID
43605ef1 559 bool "Intel MID platform support"
43605ef1 560 depends on X86_EXTENDED_PLATFORM
edc6bc78 561 depends on X86_PLATFORM_DEVICES
1ea7c673 562 depends on PCI
3fda5bb4 563 depends on X86_64 || (PCI_GOANY && X86_32)
1ea7c673 564 depends on X86_IO_APIC
7c9c3a1e 565 select SFI
4cb9b00f 566 select I2C
7c9c3a1e 567 select DW_APB_TIMER
1ea7c673 568 select APB_TIMER
1ea7c673 569 select INTEL_SCU_IPC
15a713df 570 select MFD_INTEL_MSIC
1ea7c673 571 ---help---
4cb9b00f
DC
572 Select to build a kernel capable of supporting Intel MID (Mobile
573 Internet Device) platform systems which do not have the PCI legacy
574 interfaces. If you are building for a PC class system say N here.
1ea7c673 575
4cb9b00f
DC
576 Intel MID platforms are based on an Intel processor and chipset which
577 consume less power than most of the x86 derivatives.
43605ef1 578
8bbc2a13
BD
579config X86_INTEL_QUARK
580 bool "Intel Quark platform support"
581 depends on X86_32
582 depends on X86_EXTENDED_PLATFORM
583 depends on X86_PLATFORM_DEVICES
584 depends on X86_TSC
585 depends on PCI
586 depends on PCI_GOANY
587 depends on X86_IO_APIC
588 select IOSF_MBI
589 select INTEL_IMR
9ab6eb51 590 select COMMON_CLK
8bbc2a13
BD
591 ---help---
592 Select to include support for Quark X1000 SoC.
593 Say Y here if you have a Quark based system such as the Arduino
594 compatible Intel Galileo.
595
3d48aab1
MW
596config X86_INTEL_LPSS
597 bool "Intel Low Power Subsystem Support"
eebb3e8d 598 depends on X86 && ACPI
3d48aab1 599 select COMMON_CLK
0f531431 600 select PINCTRL
eebb3e8d 601 select IOSF_MBI
3d48aab1
MW
602 ---help---
603 Select to build support for Intel Low Power Subsystem such as
604 found on Intel Lynxpoint PCH. Selecting this option enables
0f531431
MN
605 things like clock tree (common clock framework) and pincontrol
606 which are needed by the LPSS peripheral drivers.
3d48aab1 607
92082a88
KX
608config X86_AMD_PLATFORM_DEVICE
609 bool "AMD ACPI2Platform devices support"
610 depends on ACPI
611 select COMMON_CLK
612 select PINCTRL
613 ---help---
614 Select to interpret AMD specific ACPI device to platform device
615 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
616 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
617 implemented under PINCTRL subsystem.
618
ced3ce76
DB
619config IOSF_MBI
620 tristate "Intel SoC IOSF Sideband support for SoC platforms"
621 depends on PCI
622 ---help---
623 This option enables sideband register access support for Intel SoC
624 platforms. On these platforms the IOSF sideband is used in lieu of
625 MSR's for some register accesses, mostly but not limited to thermal
626 and power. Drivers may query the availability of this device to
627 determine if they need the sideband in order to work on these
628 platforms. The sideband is available on the following SoC products.
629 This list is not meant to be exclusive.
630 - BayTrail
631 - Braswell
632 - Quark
633
634 You should say Y if you are running a kernel on one of these SoC's.
635
ed2226bd
DB
636config IOSF_MBI_DEBUG
637 bool "Enable IOSF sideband access through debugfs"
638 depends on IOSF_MBI && DEBUG_FS
639 ---help---
640 Select this option to expose the IOSF sideband access registers (MCR,
641 MDR, MCRX) through debugfs to write and read register information from
642 different units on the SoC. This is most useful for obtaining device
643 state information for debug and analysis. As this is a general access
644 mechanism, users of this option would have specific knowledge of the
645 device they want to access.
646
647 If you don't require the option or are in doubt, say N.
648
c5c606d9
RT
649config X86_RDC321X
650 bool "RDC R-321x SoC"
506f1d07 651 depends on X86_32
c5c606d9
RT
652 depends on X86_EXTENDED_PLATFORM
653 select M486
654 select X86_REBOOTFIXUPS
655 ---help---
656 This option is needed for RDC R-321x system-on-chip, also known
657 as R-8610-(G).
658 If you don't have one of these chips, you should say N here.
659
e0c7ae37 660config X86_32_NON_STANDARD
9c398017
IM
661 bool "Support non-standard 32-bit SMP architectures"
662 depends on X86_32 && SMP
c5c606d9 663 depends on X86_EXTENDED_PLATFORM
8f9ca475 664 ---help---
b5660ba7
PA
665 This option compiles in the bigsmp and STA2X11 default
666 subarchitectures. It is intended for a generic binary
667 kernel. If you select them all, kernel will probe it one by
668 one and will fallback to default.
d49c4288 669
c5c606d9 670# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 671
d949f36f 672config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 673 def_bool y
d949f36f
LT
674 # MCE code calls memory_failure():
675 depends on X86_MCE
676 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
d949f36f
LT
677 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
678 depends on X86_64 || !SPARSEMEM
679 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 680
83125a3a
AR
681config STA2X11
682 bool "STA2X11 Companion Chip Support"
683 depends on X86_32_NON_STANDARD && PCI
b6e05477 684 select ARCH_HAS_PHYS_TO_DMA
83125a3a
AR
685 select X86_DEV_DMA_OPS
686 select X86_DMA_REMAP
687 select SWIOTLB
688 select MFD_STA2X11
0145071b 689 select GPIOLIB
83125a3a
AR
690 default n
691 ---help---
692 This adds support for boards based on the STA2X11 IO-Hub,
693 a.k.a. "ConneXt". The chip is used in place of the standard
694 PC chipset, so all "standard" peripherals are missing. If this
695 option is selected the kernel will still be able to boot on
696 standard PC machines.
697
82148d1d
S
698config X86_32_IRIS
699 tristate "Eurobraille/Iris poweroff module"
700 depends on X86_32
701 ---help---
702 The Iris machines from EuroBraille do not have APM or ACPI support
703 to shut themselves down properly. A special I/O sequence is
704 needed to do so, which is what this module does at
705 kernel shutdown.
706
707 This is only for Iris machines from EuroBraille.
708
709 If unused, say N.
710
ae1e9130 711config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
712 def_bool y
713 prompt "Single-depth WCHAN output"
a87d0914 714 depends on X86
8f9ca475 715 ---help---
506f1d07
SR
716 Calculate simpler /proc/<PID>/wchan values. If this option
717 is disabled then wchan values will recurse back to the
718 caller function. This provides more accurate wchan values,
719 at the expense of slightly more scheduling overhead.
720
721 If in doubt, say "Y".
722
6276a074
BP
723menuconfig HYPERVISOR_GUEST
724 bool "Linux guest support"
8f9ca475 725 ---help---
6276a074
BP
726 Say Y here to enable options for running Linux under various hyper-
727 visors. This option enables basic hypervisor detection and platform
728 setup.
506f1d07 729
6276a074
BP
730 If you say N, all options in this submenu will be skipped and
731 disabled, and Linux guest support won't be built in.
506f1d07 732
6276a074 733if HYPERVISOR_GUEST
506f1d07 734
e61bd94a
EPH
735config PARAVIRT
736 bool "Enable paravirtualization code"
8f9ca475 737 ---help---
e61bd94a
EPH
738 This changes the kernel so it can modify itself when it is run
739 under a hypervisor, potentially improving performance significantly
740 over full virtualization. However, when run without a hypervisor
741 the kernel is theoretically slower and slightly larger.
742
6276a074
BP
743config PARAVIRT_DEBUG
744 bool "paravirt-ops debugging"
745 depends on PARAVIRT && DEBUG_KERNEL
746 ---help---
747 Enable to debug paravirt_ops internals. Specifically, BUG if
748 a paravirt_op is missing when it is called.
749
b4ecc126
JF
750config PARAVIRT_SPINLOCKS
751 bool "Paravirtualization layer for spinlocks"
6ea30386 752 depends on PARAVIRT && SMP
b4ecc126
JF
753 ---help---
754 Paravirtualized spinlocks allow a pvops backend to replace the
755 spinlock implementation with something virtualization-friendly
756 (for example, block the virtual CPU rather than spinning).
757
4c4e4f61
R
758 It has a minimal impact on native kernels and gives a nice performance
759 benefit on paravirtualized KVM / Xen kernels.
b4ecc126 760
4c4e4f61 761 If you are unsure how to answer this question, answer Y.
b4ecc126 762
45e898b7
WL
763config QUEUED_LOCK_STAT
764 bool "Paravirt queued spinlock statistics"
cfd8983f 765 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
45e898b7
WL
766 ---help---
767 Enable the collection of statistical data on the slowpath
768 behavior of paravirtualized queued spinlocks and report
769 them on debugfs.
770
6276a074 771source "arch/x86/xen/Kconfig"
7af192c9 772
6276a074
BP
773config KVM_GUEST
774 bool "KVM Guest support (including kvmclock)"
775 depends on PARAVIRT
776 select PARAVIRT_CLOCK
777 default y
8f9ca475 778 ---help---
6276a074
BP
779 This option enables various optimizations for running under the KVM
780 hypervisor. It includes a paravirtualized clock, so that instead
781 of relying on a PIT (or probably other) emulation by the
782 underlying device model, the host provides the guest with
783 timing infrastructure such as time of day, and system time
506f1d07 784
1e20eb85
SV
785config KVM_DEBUG_FS
786 bool "Enable debug information for KVM Guests in debugfs"
787 depends on KVM_GUEST && DEBUG_FS
788 default n
789 ---help---
790 This option enables collection of various statistics for KVM guest.
791 Statistics are displayed in debugfs filesystem. Enabling this option
792 may incur significant overhead.
793
6276a074
BP
794config PARAVIRT_TIME_ACCOUNTING
795 bool "Paravirtual steal time accounting"
796 depends on PARAVIRT
797 default n
8f9ca475 798 ---help---
6276a074
BP
799 Select this option to enable fine granularity task steal time
800 accounting. Time spent executing other tasks in parallel with
801 the current vCPU is discounted from the vCPU power. To account for
802 that, there can be a small performance impact.
803
804 If in doubt, say N here.
805
806config PARAVIRT_CLOCK
807 bool
97349135 808
4a362601
JK
809config JAILHOUSE_GUEST
810 bool "Jailhouse non-root cell support"
abde587b 811 depends on X86_64 && PCI
87e65d05 812 select X86_PM_TIMER
4a362601
JK
813 ---help---
814 This option allows to run Linux as guest in a Jailhouse non-root
815 cell. You can leave this option disabled if you only want to start
816 Jailhouse and run Linux afterwards in the root cell.
817
6276a074 818endif #HYPERVISOR_GUEST
97349135 819
08677214 820config NO_BOOTMEM
774ea0bc 821 def_bool y
08677214 822
506f1d07
SR
823source "arch/x86/Kconfig.cpu"
824
825config HPET_TIMER
3c2362e6 826 def_bool X86_64
506f1d07 827 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
828 ---help---
829 Use the IA-PC HPET (High Precision Event Timer) to manage
830 time in preference to the PIT and RTC, if a HPET is
831 present.
832 HPET is the next generation timer replacing legacy 8254s.
833 The HPET provides a stable time base on SMP
834 systems, unlike the TSC, but it is more expensive to access,
4e7f9df2
MT
835 as it is off-chip. The interface used is documented
836 in the HPET spec, revision 1.
506f1d07 837
8f9ca475
IM
838 You can safely choose Y here. However, HPET will only be
839 activated if the platform and the BIOS support this feature.
840 Otherwise the 8254 will be used for timing services.
506f1d07 841
8f9ca475 842 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
843
844config HPET_EMULATE_RTC
3c2362e6 845 def_bool y
9d8af78b 846 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 847
bb24c471 848config APB_TIMER
933b9463
AC
849 def_bool y if X86_INTEL_MID
850 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
06c3df49 851 select DW_APB_TIMER
a0c3832a 852 depends on X86_INTEL_MID && SFI
bb24c471
JP
853 help
854 APB timer is the replacement for 8254, HPET on X86 MID platforms.
855 The APBT provides a stable time base on SMP
856 systems, unlike the TSC, but it is more expensive to access,
857 as it is off-chip. APB timers are always running regardless of CPU
858 C states, they are used as per CPU clockevent device when possible.
859
6a108a14 860# Mark as expert because too many people got it wrong.
506f1d07 861# The code disables itself when not needed.
7ae9392c
TP
862config DMI
863 default y
cf074402 864 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
6a108a14 865 bool "Enable DMI scanning" if EXPERT
8f9ca475 866 ---help---
7ae9392c
TP
867 Enabled scanning of DMI to identify machine quirks. Say Y
868 here unless you have verified that your setup is not
869 affected by entries in the DMI blacklist. Required by PNP
870 BIOS code.
871
506f1d07 872config GART_IOMMU
38901f1c 873 bool "Old AMD GART IOMMU support"
a4ce5a48 874 select IOMMU_HELPER
506f1d07 875 select SWIOTLB
23ac4ae8 876 depends on X86_64 && PCI && AMD_NB
8f9ca475 877 ---help---
ced3c42c
IM
878 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
879 GART based hardware IOMMUs.
880
881 The GART supports full DMA access for devices with 32-bit access
882 limitations, on systems with more than 3 GB. This is usually needed
883 for USB, sound, many IDE/SATA chipsets and some other devices.
884
885 Newer systems typically have a modern AMD IOMMU, supported via
886 the CONFIG_AMD_IOMMU=y config option.
887
888 In normal configurations this driver is only active when needed:
889 there's more than 3 GB of memory and the system contains a
890 32-bit limited device.
891
892 If unsure, say Y.
506f1d07
SR
893
894config CALGARY_IOMMU
895 bool "IBM Calgary IOMMU support"
a4ce5a48 896 select IOMMU_HELPER
506f1d07 897 select SWIOTLB
6ea30386 898 depends on X86_64 && PCI
8f9ca475 899 ---help---
506f1d07
SR
900 Support for hardware IOMMUs in IBM's xSeries x366 and x460
901 systems. Needed to run systems with more than 3GB of memory
902 properly with 32-bit PCI devices that do not support DAC
903 (Double Address Cycle). Calgary also supports bus level
904 isolation, where all DMAs pass through the IOMMU. This
905 prevents them from going anywhere except their intended
906 destination. This catches hard-to-find kernel bugs and
907 mis-behaving drivers and devices that do not use the DMA-API
908 properly to set up their DMA buffers. The IOMMU can be
909 turned off at boot time with the iommu=off parameter.
910 Normally the kernel will make the right choice by itself.
911 If unsure, say Y.
912
913config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
914 def_bool y
915 prompt "Should Calgary be enabled by default?"
506f1d07 916 depends on CALGARY_IOMMU
8f9ca475 917 ---help---
506f1d07
SR
918 Should Calgary be enabled by default? if you choose 'y', Calgary
919 will be used (if it exists). If you choose 'n', Calgary will not be
920 used even if it exists. If you choose 'n' and would like to use
921 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
922 If unsure, say Y.
506f1d07 923
1184dc2f 924config MAXSMP
ddb0c5a6 925 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
6ea30386 926 depends on X86_64 && SMP && DEBUG_KERNEL
36f5101a 927 select CPUMASK_OFFSTACK
8f9ca475 928 ---help---
ddb0c5a6 929 Enable maximum number of CPUS and NUMA Nodes for this architecture.
1184dc2f 930 If unsure, say N.
506f1d07 931
aec6487e
IM
932#
933# The maximum number of CPUs supported:
934#
935# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
936# and which can be configured interactively in the
937# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
938#
939# The ranges are different on 32-bit and 64-bit kernels, depending on
940# hardware capabilities and scalability features of the kernel.
941#
942# ( If MAXSMP is enabled we just use the highest possible value and disable
943# interactive configuration. )
944#
945
946config NR_CPUS_RANGE_BEGIN
a0d0bb4d 947 int
aec6487e
IM
948 default NR_CPUS_RANGE_END if MAXSMP
949 default 1 if !SMP
950 default 2
a0d0bb4d 951
aec6487e 952config NR_CPUS_RANGE_END
a0d0bb4d 953 int
aec6487e
IM
954 depends on X86_32
955 default 64 if SMP && X86_BIGSMP
956 default 8 if SMP && !X86_BIGSMP
957 default 1 if !SMP
a0d0bb4d 958
aec6487e 959config NR_CPUS_RANGE_END
a0d0bb4d 960 int
aec6487e
IM
961 depends on X86_64
962 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
963 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
964 default 1 if !SMP
a0d0bb4d 965
aec6487e 966config NR_CPUS_DEFAULT
a0d0bb4d
RD
967 int
968 depends on X86_32
aec6487e
IM
969 default 32 if X86_BIGSMP
970 default 8 if SMP
971 default 1 if !SMP
a0d0bb4d 972
aec6487e 973config NR_CPUS_DEFAULT
a0d0bb4d
RD
974 int
975 depends on X86_64
aec6487e
IM
976 default 8192 if MAXSMP
977 default 64 if SMP
978 default 1 if !SMP
a0d0bb4d 979
506f1d07 980config NR_CPUS
36f5101a 981 int "Maximum number of CPUs" if SMP && !MAXSMP
aec6487e
IM
982 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
983 default NR_CPUS_DEFAULT
8f9ca475 984 ---help---
506f1d07 985 This allows you to specify the maximum number of CPUs which this
bb61ccc7 986 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
cad14bb9 987 supported value is 8192, otherwise the maximum value is 512. The
506f1d07
SR
988 minimum value which makes sense is 2.
989
aec6487e
IM
990 This is purely to save memory: each supported CPU adds about 8KB
991 to the kernel image.
506f1d07
SR
992
993config SCHED_SMT
994 bool "SMT (Hyperthreading) scheduler support"
c8e56d20 995 depends on SMP
8f9ca475 996 ---help---
506f1d07
SR
997 SMT scheduler support improves the CPU scheduler's decision making
998 when dealing with Intel Pentium 4 chips with HyperThreading at a
999 cost of slightly increased overhead in some places. If unsure say
1000 N here.
1001
1002config SCHED_MC
3c2362e6
HH
1003 def_bool y
1004 prompt "Multi-core scheduler support"
c8e56d20 1005 depends on SMP
8f9ca475 1006 ---help---
506f1d07
SR
1007 Multi-core scheduler support improves the CPU scheduler's decision
1008 making when dealing with multi-core CPU chips at a cost of slightly
1009 increased overhead in some places. If unsure say N here.
1010
de966cf4
TC
1011config SCHED_MC_PRIO
1012 bool "CPU core priorities scheduler support"
0a21fc12
IM
1013 depends on SCHED_MC && CPU_SUP_INTEL
1014 select X86_INTEL_PSTATE
1015 select CPU_FREQ
de966cf4 1016 default y
5e76b2ab 1017 ---help---
0a21fc12
IM
1018 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1019 core ordering determined at manufacturing time, which allows
1020 certain cores to reach higher turbo frequencies (when running
1021 single threaded workloads) than others.
de966cf4 1022
0a21fc12
IM
1023 Enabling this kernel feature teaches the scheduler about
1024 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1025 scheduler's CPU selection logic accordingly, so that higher
1026 overall system performance can be achieved.
de966cf4 1027
0a21fc12 1028 This feature will have no effect on CPUs without this feature.
de966cf4 1029
0a21fc12 1030 If unsure say Y here.
5e76b2ab 1031
506f1d07
SR
1032source "kernel/Kconfig.preempt"
1033
30b8b006
TG
1034config UP_LATE_INIT
1035 def_bool y
ba360f88 1036 depends on !SMP && X86_LOCAL_APIC
30b8b006 1037
506f1d07 1038config X86_UP_APIC
50849eef
JB
1039 bool "Local APIC support on uniprocessors" if !PCI_MSI
1040 default PCI_MSI
38a1dfda 1041 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 1042 ---help---
506f1d07
SR
1043 A local APIC (Advanced Programmable Interrupt Controller) is an
1044 integrated interrupt controller in the CPU. If you have a single-CPU
1045 system which has a processor with a local APIC, you can say Y here to
1046 enable and use it. If you say Y here even though your machine doesn't
1047 have a local APIC, then the kernel will still run with no slowdown at
1048 all. The local APIC supports CPU-generated self-interrupts (timer,
1049 performance counters), and the NMI watchdog which detects hard
1050 lockups.
1051
1052config X86_UP_IOAPIC
1053 bool "IO-APIC support on uniprocessors"
1054 depends on X86_UP_APIC
8f9ca475 1055 ---help---
506f1d07
SR
1056 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1057 SMP-capable replacement for PC-style interrupt controllers. Most
1058 SMP systems and many recent uniprocessor systems have one.
1059
1060 If you have a single-CPU system with an IO-APIC, you can say Y here
1061 to use it. If you say Y here even though your machine doesn't have
1062 an IO-APIC, then the kernel will still run with no slowdown at all.
1063
1064config X86_LOCAL_APIC
3c2362e6 1065 def_bool y
0dbc6078 1066 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
b5dc8e6c 1067 select IRQ_DOMAIN_HIERARCHY
52f518a3 1068 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
506f1d07
SR
1069
1070config X86_IO_APIC
b1da1e71
JB
1071 def_bool y
1072 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
506f1d07 1073
41b9eb26
SA
1074config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1075 bool "Reroute for broken boot IRQs"
41b9eb26 1076 depends on X86_IO_APIC
8f9ca475 1077 ---help---
41b9eb26
SA
1078 This option enables a workaround that fixes a source of
1079 spurious interrupts. This is recommended when threaded
1080 interrupt handling is used on systems where the generation of
1081 superfluous "boot interrupts" cannot be disabled.
1082
1083 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1084 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1085 kernel does during interrupt handling). On chipsets where this
1086 boot IRQ generation cannot be disabled, this workaround keeps
1087 the original IRQ line masked so that only the equivalent "boot
1088 IRQ" is delivered to the CPUs. The workaround also tells the
1089 kernel to set up the IRQ handler on the boot IRQ line. In this
1090 way only one interrupt is delivered to the kernel. Otherwise
1091 the spurious second interrupt may cause the kernel to bring
1092 down (vital) interrupt lines.
1093
1094 Only affects "broken" chipsets. Interrupt sharing may be
1095 increased on these systems.
1096
506f1d07 1097config X86_MCE
bab9bc65 1098 bool "Machine Check / overheating reporting"
648ed940 1099 select GENERIC_ALLOCATOR
e57dbaf7 1100 default y
506f1d07 1101 ---help---
bab9bc65
AK
1102 Machine Check support allows the processor to notify the
1103 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 1104 The action the kernel takes depends on the severity of the problem,
bab9bc65 1105 ranging from warning messages to halting the machine.
4efc0670 1106
5de97c9f
TL
1107config X86_MCELOG_LEGACY
1108 bool "Support for deprecated /dev/mcelog character device"
1109 depends on X86_MCE
1110 ---help---
1111 Enable support for /dev/mcelog which is needed by the old mcelog
1112 userspace logging daemon. Consider switching to the new generation
1113 rasdaemon solution.
1114
506f1d07 1115config X86_MCE_INTEL
3c2362e6
HH
1116 def_bool y
1117 prompt "Intel MCE features"
c1ebf835 1118 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 1119 ---help---
506f1d07
SR
1120 Additional support for intel specific MCE features such as
1121 the thermal monitor.
1122
1123config X86_MCE_AMD
3c2362e6
HH
1124 def_bool y
1125 prompt "AMD MCE features"
f5382de9 1126 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
8f9ca475 1127 ---help---
506f1d07
SR
1128 Additional support for AMD specific MCE features such as
1129 the DRAM Error Threshold.
1130
4efc0670 1131config X86_ANCIENT_MCE
6fc108a0 1132 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 1133 depends on X86_32 && X86_MCE
cd13adcc
HS
1134 ---help---
1135 Include support for machine check handling on old Pentium 5 or WinChip
5065a706 1136 systems. These typically need to be enabled explicitly on the command
cd13adcc 1137 line.
4efc0670 1138
b2762686
AK
1139config X86_MCE_THRESHOLD
1140 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 1141 def_bool y
b2762686 1142
ea149b36 1143config X86_MCE_INJECT
bc8e80d5 1144 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
ea149b36
AK
1145 tristate "Machine check injector support"
1146 ---help---
1147 Provide support for injecting machine checks for testing purposes.
1148 If you don't know what a machine check is and you don't do kernel
1149 QA it is safe to say n.
1150
4efc0670
AK
1151config X86_THERMAL_VECTOR
1152 def_bool y
5bb38adc 1153 depends on X86_MCE_INTEL
4efc0670 1154
07dc900e 1155source "arch/x86/events/Kconfig"
e633c65a 1156
5aef51c3 1157config X86_LEGACY_VM86
1e642812 1158 bool "Legacy VM86 support"
5aef51c3 1159 default n
506f1d07 1160 depends on X86_32
8f9ca475 1161 ---help---
5aef51c3
AL
1162 This option allows user programs to put the CPU into V8086
1163 mode, which is an 80286-era approximation of 16-bit real mode.
1164
1165 Some very old versions of X and/or vbetool require this option
1166 for user mode setting. Similarly, DOSEMU will use it if
1167 available to accelerate real mode DOS programs. However, any
1168 recent version of DOSEMU, X, or vbetool should be fully
1169 functional even without kernel VM86 support, as they will all
1e642812
IM
1170 fall back to software emulation. Nevertheless, if you are using
1171 a 16-bit DOS program where 16-bit performance matters, vm86
1172 mode might be faster than emulation and you might want to
1173 enable this option.
5aef51c3 1174
1e642812
IM
1175 Note that any app that works on a 64-bit kernel is unlikely to
1176 need this option, as 64-bit kernels don't, and can't, support
1177 V8086 mode. This option is also unrelated to 16-bit protected
1178 mode and is not needed to run most 16-bit programs under Wine.
5aef51c3 1179
1e642812
IM
1180 Enabling this option increases the complexity of the kernel
1181 and slows down exception handling a tiny bit.
5aef51c3 1182
1e642812 1183 If unsure, say N here.
5aef51c3
AL
1184
1185config VM86
1186 bool
1187 default X86_LEGACY_VM86
34273f41
PA
1188
1189config X86_16BIT
1190 bool "Enable support for 16-bit segments" if EXPERT
1191 default y
a5b9e5a2 1192 depends on MODIFY_LDT_SYSCALL
34273f41
PA
1193 ---help---
1194 This option is required by programs like Wine to run 16-bit
1195 protected mode legacy code on x86 processors. Disabling
1196 this option saves about 300 bytes on i386, or around 6K text
1197 plus 16K runtime memory on x86-64,
1198
1199config X86_ESPFIX32
1200 def_bool y
1201 depends on X86_16BIT && X86_32
506f1d07 1202
197725de
PA
1203config X86_ESPFIX64
1204 def_bool y
34273f41 1205 depends on X86_16BIT && X86_64
506f1d07 1206
1ad83c85
AL
1207config X86_VSYSCALL_EMULATION
1208 bool "Enable vsyscall emulation" if EXPERT
1209 default y
1210 depends on X86_64
1211 ---help---
1212 This enables emulation of the legacy vsyscall page. Disabling
1213 it is roughly equivalent to booting with vsyscall=none, except
1214 that it will also disable the helpful warning if a program
1215 tries to use a vsyscall. With this option set to N, offending
1216 programs will just segfault, citing addresses of the form
1217 0xffffffffff600?00.
1218
1219 This option is required by many programs built before 2013, and
1220 care should be used even with newer programs if set to N.
1221
1222 Disabling this option saves about 7K of kernel size and
1223 possibly 4K of additional runtime pagetable memory.
1224
506f1d07
SR
1225config TOSHIBA
1226 tristate "Toshiba Laptop support"
1227 depends on X86_32
1228 ---help---
1229 This adds a driver to safely access the System Management Mode of
1230 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1231 not work on models with a Phoenix BIOS. The System Management Mode
1232 is used to set the BIOS and power saving options on Toshiba portables.
1233
1234 For information on utilities to make use of this driver see the
1235 Toshiba Linux utilities web site at:
1236 <http://www.buzzard.org.uk/toshiba/>.
1237
1238 Say Y if you intend to run this kernel on a Toshiba portable.
1239 Say N otherwise.
1240
1241config I8K
039ae585 1242 tristate "Dell i8k legacy laptop support"
949a9d70 1243 select HWMON
039ae585 1244 select SENSORS_DELL_SMM
506f1d07 1245 ---help---
039ae585
PR
1246 This option enables legacy /proc/i8k userspace interface in hwmon
1247 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1248 temperature and allows controlling fan speeds of Dell laptops via
1249 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1250 it reports also power and hotkey status. For fan speed control is
1251 needed userspace package i8kutils.
1252
1253 Say Y if you intend to run this kernel on old Dell laptops or want to
1254 use userspace package i8kutils.
506f1d07
SR
1255 Say N otherwise.
1256
1257config X86_REBOOTFIXUPS
9ba16087
JB
1258 bool "Enable X86 board specific fixups for reboot"
1259 depends on X86_32
506f1d07
SR
1260 ---help---
1261 This enables chipset and/or board specific fixups to be done
1262 in order to get reboot to work correctly. This is only needed on
1263 some combinations of hardware and BIOS. The symptom, for which
1264 this config is intended, is when reboot ends with a stalled/hung
1265 system.
1266
1267 Currently, the only fixup is for the Geode machines using
5e3a77e9 1268 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
1269
1270 Say Y if you want to enable the fixup. Currently, it's safe to
1271 enable this option even if you don't need it.
1272 Say N otherwise.
1273
1274config MICROCODE
9a2bc335
BP
1275 bool "CPU microcode loading support"
1276 default y
80030e3d 1277 depends on CPU_SUP_AMD || CPU_SUP_INTEL
506f1d07
SR
1278 select FW_LOADER
1279 ---help---
1280 If you say Y here, you will be able to update the microcode on
5f9c01aa
BP
1281 Intel and AMD processors. The Intel support is for the IA32 family,
1282 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1283 AMD support is for families 0x10 and later. You will obviously need
1284 the actual microcode binary data itself which is not shipped with
1285 the Linux kernel.
1286
1287 The preferred method to load microcode from a detached initrd is described
1897a969 1288 in Documentation/x86/microcode.txt. For that you need to enable
5f9c01aa
BP
1289 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1290 initrd for microcode blobs.
1291
c508c46e
BG
1292 In addition, you can build the microcode into the kernel. For that you
1293 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1294 config option.
506f1d07 1295
8d86f390 1296config MICROCODE_INTEL
e43f6e67 1297 bool "Intel microcode loading support"
8f9ca475
IM
1298 depends on MICROCODE
1299 default MICROCODE
1300 select FW_LOADER
1301 ---help---
1302 This options enables microcode patch loading support for Intel
1303 processors.
1304
b8989db9
A
1305 For the current Intel microcode data package go to
1306 <https://downloadcenter.intel.com> and search for
1307 'Linux Processor Microcode Data File'.
8d86f390 1308
80cc9f10 1309config MICROCODE_AMD
e43f6e67 1310 bool "AMD microcode loading support"
8f9ca475
IM
1311 depends on MICROCODE
1312 select FW_LOADER
1313 ---help---
1314 If you select this option, microcode patch loading support for AMD
1315 processors will be enabled.
80cc9f10 1316
8f9ca475 1317config MICROCODE_OLD_INTERFACE
3c2362e6 1318 def_bool y
506f1d07 1319 depends on MICROCODE
506f1d07
SR
1320
1321config X86_MSR
1322 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1323 ---help---
506f1d07
SR
1324 This device gives privileged processes access to the x86
1325 Model-Specific Registers (MSRs). It is a character device with
1326 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1327 MSR accesses are directed to a specific CPU on multi-processor
1328 systems.
1329
1330config X86_CPUID
1331 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1332 ---help---
506f1d07
SR
1333 This device gives processes access to the x86 CPUID instruction to
1334 be executed on a specific processor. It is a character device
1335 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1336 /dev/cpu/31/cpuid.
1337
1338choice
1339 prompt "High Memory Support"
6fc108a0 1340 default HIGHMEM4G
506f1d07
SR
1341 depends on X86_32
1342
1343config NOHIGHMEM
1344 bool "off"
506f1d07
SR
1345 ---help---
1346 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1347 However, the address space of 32-bit x86 processors is only 4
1348 Gigabytes large. That means that, if you have a large amount of
1349 physical memory, not all of it can be "permanently mapped" by the
1350 kernel. The physical memory that's not permanently mapped is called
1351 "high memory".
1352
1353 If you are compiling a kernel which will never run on a machine with
1354 more than 1 Gigabyte total physical RAM, answer "off" here (default
1355 choice and suitable for most users). This will result in a "3GB/1GB"
1356 split: 3GB are mapped so that each process sees a 3GB virtual memory
1357 space and the remaining part of the 4GB virtual memory space is used
1358 by the kernel to permanently map as much physical memory as
1359 possible.
1360
1361 If the machine has between 1 and 4 Gigabytes physical RAM, then
1362 answer "4GB" here.
1363
1364 If more than 4 Gigabytes is used then answer "64GB" here. This
1365 selection turns Intel PAE (Physical Address Extension) mode on.
1366 PAE implements 3-level paging on IA32 processors. PAE is fully
1367 supported by Linux, PAE mode is implemented on all recent Intel
1368 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1369 then the kernel will not boot on CPUs that don't support PAE!
1370
1371 The actual amount of total physical memory will either be
1372 auto detected or can be forced by using a kernel command line option
1373 such as "mem=256M". (Try "man bootparam" or see the documentation of
1374 your boot loader (lilo or loadlin) about how to pass options to the
1375 kernel at boot time.)
1376
1377 If unsure, say "off".
1378
1379config HIGHMEM4G
1380 bool "4GB"
8f9ca475 1381 ---help---
506f1d07
SR
1382 Select this if you have a 32-bit processor and between 1 and 4
1383 gigabytes of physical RAM.
1384
1385config HIGHMEM64G
1386 bool "64GB"
69b8d3fc 1387 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
506f1d07 1388 select X86_PAE
8f9ca475 1389 ---help---
506f1d07
SR
1390 Select this if you have a 32-bit processor and more than 4
1391 gigabytes of physical RAM.
1392
1393endchoice
1394
1395choice
6a108a14 1396 prompt "Memory split" if EXPERT
506f1d07
SR
1397 default VMSPLIT_3G
1398 depends on X86_32
8f9ca475 1399 ---help---
506f1d07
SR
1400 Select the desired split between kernel and user memory.
1401
1402 If the address range available to the kernel is less than the
1403 physical memory installed, the remaining memory will be available
1404 as "high memory". Accessing high memory is a little more costly
1405 than low memory, as it needs to be mapped into the kernel first.
1406 Note that increasing the kernel address space limits the range
1407 available to user programs, making the address space there
1408 tighter. Selecting anything other than the default 3G/1G split
1409 will also likely make your kernel incompatible with binary-only
1410 kernel modules.
1411
1412 If you are not absolutely sure what you are doing, leave this
1413 option alone!
1414
1415 config VMSPLIT_3G
1416 bool "3G/1G user/kernel split"
1417 config VMSPLIT_3G_OPT
1418 depends on !X86_PAE
1419 bool "3G/1G user/kernel split (for full 1G low memory)"
1420 config VMSPLIT_2G
1421 bool "2G/2G user/kernel split"
1422 config VMSPLIT_2G_OPT
1423 depends on !X86_PAE
1424 bool "2G/2G user/kernel split (for full 2G low memory)"
1425 config VMSPLIT_1G
1426 bool "1G/3G user/kernel split"
1427endchoice
1428
1429config PAGE_OFFSET
1430 hex
1431 default 0xB0000000 if VMSPLIT_3G_OPT
1432 default 0x80000000 if VMSPLIT_2G
1433 default 0x78000000 if VMSPLIT_2G_OPT
1434 default 0x40000000 if VMSPLIT_1G
1435 default 0xC0000000
1436 depends on X86_32
1437
1438config HIGHMEM
3c2362e6 1439 def_bool y
506f1d07 1440 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1441
1442config X86_PAE
9ba16087 1443 bool "PAE (Physical Address Extension) Support"
506f1d07 1444 depends on X86_32 && !HIGHMEM4G
d4a451d5 1445 select PHYS_ADDR_T_64BIT
9d99c712 1446 select SWIOTLB
8f9ca475 1447 ---help---
506f1d07
SR
1448 PAE is required for NX support, and furthermore enables
1449 larger swapspace support for non-overcommit purposes. It
1450 has the cost of more pagetable lookup overhead, and also
1451 consumes more pagetable space per process.
1452
77ef56e4
KS
1453config X86_5LEVEL
1454 bool "Enable 5-level page tables support"
eedb92ab 1455 select DYNAMIC_MEMORY_LAYOUT
162434e7 1456 select SPARSEMEM_VMEMMAP
77ef56e4
KS
1457 depends on X86_64
1458 ---help---
1459 5-level paging enables access to larger address space:
1460 upto 128 PiB of virtual address space and 4 PiB of
1461 physical address space.
1462
1463 It will be supported by future Intel CPUs.
1464
6657fca0
KS
1465 A kernel with the option enabled can be booted on machines that
1466 support 4- or 5-level paging.
77ef56e4
KS
1467
1468 See Documentation/x86/x86_64/5level-paging.txt for more
1469 information.
1470
1471 Say N if unsure.
1472
10971ab2 1473config X86_DIRECT_GBPAGES
e5008abe 1474 def_bool y
4675ff05 1475 depends on X86_64 && !DEBUG_PAGEALLOC
8f9ca475 1476 ---help---
10971ab2
IM
1477 Certain kernel features effectively disable kernel
1478 linear 1 GB mappings (even if the CPU otherwise
1479 supports them), so don't confuse the user by printing
1480 that we have them enabled.
9e899816 1481
7744ccdb
TL
1482config ARCH_HAS_MEM_ENCRYPT
1483 def_bool y
1484
1485config AMD_MEM_ENCRYPT
1486 bool "AMD Secure Memory Encryption (SME) support"
1487 depends on X86_64 && CPU_SUP_AMD
1488 ---help---
1489 Say yes to enable support for the encryption of system memory.
1490 This requires an AMD processor that supports Secure Memory
1491 Encryption (SME).
1492
1493config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1494 bool "Activate AMD Secure Memory Encryption (SME) by default"
1495 default y
1496 depends on AMD_MEM_ENCRYPT
1497 ---help---
1498 Say yes to have system memory encrypted by default if running on
1499 an AMD processor that supports Secure Memory Encryption (SME).
1500
1501 If set to Y, then the encryption of system memory can be
1502 deactivated with the mem_encrypt=off command line option.
1503
1504 If set to N, then the encryption of system memory can be
1505 activated with the mem_encrypt=on command line option.
1506
f88a68fa
TL
1507config ARCH_USE_MEMREMAP_PROT
1508 def_bool y
1509 depends on AMD_MEM_ENCRYPT
1510
506f1d07
SR
1511# Common NUMA Features
1512config NUMA
fd51b2d7 1513 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1514 depends on SMP
b5660ba7
PA
1515 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1516 default y if X86_BIGSMP
8f9ca475 1517 ---help---
506f1d07 1518 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1519
506f1d07
SR
1520 The kernel will try to allocate memory used by a CPU on the
1521 local memory controller of the CPU and add some more
1522 NUMA awareness to the kernel.
1523
c280ea5e 1524 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1525 (or later), AMD Opteron, or EM64T NUMA.
1526
b5660ba7 1527 For 32-bit this is only needed if you boot a 32-bit
7cf6c945 1528 kernel on a 64-bit NUMA platform.
fd51b2d7
KM
1529
1530 Otherwise, you should say N.
506f1d07 1531
eec1d4fa 1532config AMD_NUMA
3c2362e6
HH
1533 def_bool y
1534 prompt "Old style AMD Opteron NUMA detection"
5da0ef9a 1535 depends on X86_64 && NUMA && PCI
8f9ca475 1536 ---help---
eec1d4fa
HR
1537 Enable AMD NUMA node topology detection. You should say Y here if
1538 you have a multi processor AMD system. This uses an old method to
1539 read the NUMA configuration directly from the builtin Northbridge
1540 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1541 which also takes priority if both are compiled in.
506f1d07
SR
1542
1543config X86_64_ACPI_NUMA
3c2362e6
HH
1544 def_bool y
1545 prompt "ACPI NUMA detection"
506f1d07
SR
1546 depends on X86_64 && NUMA && ACPI && PCI
1547 select ACPI_NUMA
8f9ca475 1548 ---help---
506f1d07
SR
1549 Enable ACPI SRAT based node topology detection.
1550
6ec6e0d9
SS
1551# Some NUMA nodes have memory ranges that span
1552# other nodes. Even though a pfn is valid and
1553# between a node's start and end pfns, it may not
1554# reside on that node. See memmap_init_zone()
1555# for details.
1556config NODES_SPAN_OTHER_NODES
1557 def_bool y
1558 depends on X86_64_ACPI_NUMA
1559
506f1d07
SR
1560config NUMA_EMU
1561 bool "NUMA emulation"
1b7e03ef 1562 depends on NUMA
8f9ca475 1563 ---help---
506f1d07
SR
1564 Enable NUMA emulation. A flat machine will be split
1565 into virtual nodes when booted with "numa=fake=N", where N is the
1566 number of nodes. This is only useful for debugging.
1567
1568config NODES_SHIFT
d25e26b6 1569 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1570 range 1 10
1571 default "10" if MAXSMP
506f1d07 1572 default "6" if X86_64
506f1d07
SR
1573 default "3"
1574 depends on NEED_MULTIPLE_NODES
8f9ca475 1575 ---help---
1184dc2f 1576 Specify the maximum number of NUMA Nodes available on the target
692105b8 1577 system. Increases memory reserved to accommodate various tables.
506f1d07 1578
506f1d07 1579config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1580 def_bool y
506f1d07 1581 depends on X86_32 && DISCONTIGMEM
506f1d07 1582
506f1d07
SR
1583config ARCH_FLATMEM_ENABLE
1584 def_bool y
3b16651f 1585 depends on X86_32 && !NUMA
506f1d07
SR
1586
1587config ARCH_DISCONTIGMEM_ENABLE
1588 def_bool y
b263295d 1589 depends on NUMA && X86_32
506f1d07
SR
1590
1591config ARCH_DISCONTIGMEM_DEFAULT
1592 def_bool y
b263295d
CL
1593 depends on NUMA && X86_32
1594
506f1d07
SR
1595config ARCH_SPARSEMEM_ENABLE
1596 def_bool y
6ea30386 1597 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
506f1d07
SR
1598 select SPARSEMEM_STATIC if X86_32
1599 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1600
3b16651f
TH
1601config ARCH_SPARSEMEM_DEFAULT
1602 def_bool y
1603 depends on X86_64
1604
506f1d07
SR
1605config ARCH_SELECT_MEMORY_MODEL
1606 def_bool y
b263295d 1607 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1608
1609config ARCH_MEMORY_PROBE
a0842b70 1610 bool "Enable sysfs memory/probe interface"
3120e25e 1611 depends on X86_64 && MEMORY_HOTPLUG
a0842b70
TK
1612 help
1613 This option enables a sysfs memory/probe interface for testing.
1614 See Documentation/memory-hotplug.txt for more information.
1615 If you are unsure how to answer this question, answer N.
506f1d07 1616
3b16651f
TH
1617config ARCH_PROC_KCORE_TEXT
1618 def_bool y
1619 depends on X86_64 && PROC_KCORE
1620
a29815a3
AK
1621config ILLEGAL_POINTER_VALUE
1622 hex
1623 default 0 if X86_32
1624 default 0xdead000000000000 if X86_64
1625
506f1d07
SR
1626source "mm/Kconfig"
1627
7a67832c
DW
1628config X86_PMEM_LEGACY_DEVICE
1629 bool
1630
ec776ef6 1631config X86_PMEM_LEGACY
7a67832c 1632 tristate "Support non-standard NVDIMMs and ADR protected memory"
9f53f9fa
DW
1633 depends on PHYS_ADDR_T_64BIT
1634 depends on BLK_DEV
7a67832c 1635 select X86_PMEM_LEGACY_DEVICE
9f53f9fa 1636 select LIBNVDIMM
ec776ef6
CH
1637 help
1638 Treat memory marked using the non-standard e820 type of 12 as used
1639 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1640 The kernel will offer these regions to the 'pmem' driver so
1641 they can be used for persistent storage.
1642
1643 Say Y if unsure.
1644
506f1d07
SR
1645config HIGHPTE
1646 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1647 depends on HIGHMEM
8f9ca475 1648 ---help---
506f1d07
SR
1649 The VM uses one page table entry for each page of physical memory.
1650 For systems with a lot of RAM, this can be wasteful of precious
1651 low memory. Setting this option will put user-space page table
1652 entries in high memory.
1653
9f077871 1654config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1655 bool "Check for low memory corruption"
1656 ---help---
1657 Periodically check for memory corruption in low memory, which
1658 is suspected to be caused by BIOS. Even when enabled in the
1659 configuration, it is disabled at runtime. Enable it by
1660 setting "memory_corruption_check=1" on the kernel command
1661 line. By default it scans the low 64k of memory every 60
1662 seconds; see the memory_corruption_check_size and
1663 memory_corruption_check_period parameters in
8c27ceff 1664 Documentation/admin-guide/kernel-parameters.rst to adjust this.
8f9ca475
IM
1665
1666 When enabled with the default parameters, this option has
1667 almost no overhead, as it reserves a relatively small amount
1668 of memory and scans it infrequently. It both detects corruption
1669 and prevents it from affecting the running system.
1670
1671 It is, however, intended as a diagnostic tool; if repeatable
1672 BIOS-originated corruption always affects the same memory,
1673 you can use memmap= to prevent the kernel from using that
1674 memory.
9f077871 1675
c885df50 1676config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1677 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1678 depends on X86_CHECK_BIOS_CORRUPTION
1679 default y
8f9ca475
IM
1680 ---help---
1681 Set whether the default state of memory_corruption_check is
1682 on or off.
c885df50 1683
9ea77bdb 1684config X86_RESERVE_LOW
d0cd7425
PA
1685 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1686 default 64
1687 range 4 640
8f9ca475 1688 ---help---
d0cd7425
PA
1689 Specify the amount of low memory to reserve for the BIOS.
1690
1691 The first page contains BIOS data structures that the kernel
1692 must not use, so that page must always be reserved.
1693
1694 By default we reserve the first 64K of physical RAM, as a
1695 number of BIOSes are known to corrupt that memory range
1696 during events such as suspend/resume or monitor cable
1697 insertion, so it must not be used by the kernel.
fc381519 1698
d0cd7425
PA
1699 You can set this to 4 if you are absolutely sure that you
1700 trust the BIOS to get all its memory reservations and usages
1701 right. If you know your BIOS have problems beyond the
1702 default 64K area, you can set this to 640 to avoid using the
1703 entire low memory range.
fc381519 1704
d0cd7425
PA
1705 If you have doubts about the BIOS (e.g. suspend/resume does
1706 not work or there's kernel crashes after certain hardware
1707 hotplug events) then you might want to enable
1708 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1709 typical corruption patterns.
fc381519 1710
d0cd7425 1711 Leave this to the default value of 64 if you are unsure.
fc381519 1712
506f1d07
SR
1713config MATH_EMULATION
1714 bool
a5b9e5a2 1715 depends on MODIFY_LDT_SYSCALL
506f1d07
SR
1716 prompt "Math emulation" if X86_32
1717 ---help---
1718 Linux can emulate a math coprocessor (used for floating point
1719 operations) if you don't have one. 486DX and Pentium processors have
1720 a math coprocessor built in, 486SX and 386 do not, unless you added
1721 a 487DX or 387, respectively. (The messages during boot time can
1722 give you some hints here ["man dmesg"].) Everyone needs either a
1723 coprocessor or this emulation.
1724
1725 If you don't have a math coprocessor, you need to say Y here; if you
1726 say Y here even though you have a coprocessor, the coprocessor will
1727 be used nevertheless. (This behavior can be changed with the kernel
1728 command line option "no387", which comes handy if your coprocessor
1729 is broken. Try "man bootparam" or see the documentation of your boot
1730 loader (lilo or loadlin) about how to pass options to the kernel at
1731 boot time.) This means that it is a good idea to say Y here if you
1732 intend to use this kernel on different machines.
1733
1734 More information about the internals of the Linux math coprocessor
1735 emulation can be found in <file:arch/x86/math-emu/README>.
1736
1737 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1738 kernel, it won't hurt.
1739
1740config MTRR
6fc108a0 1741 def_bool y
6a108a14 1742 prompt "MTRR (Memory Type Range Register) support" if EXPERT
506f1d07
SR
1743 ---help---
1744 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1745 the Memory Type Range Registers (MTRRs) may be used to control
1746 processor access to memory ranges. This is most useful if you have
1747 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1748 allows bus write transfers to be combined into a larger transfer
1749 before bursting over the PCI/AGP bus. This can increase performance
1750 of image write operations 2.5 times or more. Saying Y here creates a
1751 /proc/mtrr file which may be used to manipulate your processor's
1752 MTRRs. Typically the X server should use this.
1753
1754 This code has a reasonably generic interface so that similar
1755 control registers on other processors can be easily supported
1756 as well:
1757
1758 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1759 Registers (ARRs) which provide a similar functionality to MTRRs. For
1760 these, the ARRs are used to emulate the MTRRs.
1761 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1762 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1763 write-combining. All of these processors are supported by this code
1764 and it makes sense to say Y here if you have one of them.
1765
1766 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1767 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1768 can lead to all sorts of problems, so it's good to say Y here.
1769
1770 You can safely say Y even if your machine doesn't have MTRRs, you'll
1771 just add about 9 KB to your kernel.
1772
7225e751 1773 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1774
95ffa243 1775config MTRR_SANITIZER
2ffb3501 1776 def_bool y
95ffa243
YL
1777 prompt "MTRR cleanup support"
1778 depends on MTRR
8f9ca475 1779 ---help---
aba3728c
TG
1780 Convert MTRR layout from continuous to discrete, so X drivers can
1781 add writeback entries.
95ffa243 1782
aba3728c 1783 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1784 The largest mtrr entry size for a continuous block can be set with
aba3728c 1785 mtrr_chunk_size.
95ffa243 1786
2ffb3501 1787 If unsure, say Y.
95ffa243
YL
1788
1789config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1790 int "MTRR cleanup enable value (0-1)"
1791 range 0 1
1792 default "0"
95ffa243 1793 depends on MTRR_SANITIZER
8f9ca475 1794 ---help---
f5098d62 1795 Enable mtrr cleanup default value
95ffa243 1796
12031a62
YL
1797config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1798 int "MTRR cleanup spare reg num (0-7)"
1799 range 0 7
1800 default "1"
1801 depends on MTRR_SANITIZER
8f9ca475 1802 ---help---
12031a62 1803 mtrr cleanup spare entries default, it can be changed via
aba3728c 1804 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1805
2e5d9c85 1806config X86_PAT
6fc108a0 1807 def_bool y
6a108a14 1808 prompt "x86 PAT support" if EXPERT
2a8a2719 1809 depends on MTRR
8f9ca475 1810 ---help---
2e5d9c85 1811 Use PAT attributes to setup page level cache control.
042b78e4 1812
2e5d9c85 1813 PATs are the modern equivalents of MTRRs and are much more
1814 flexible than MTRRs.
1815
1816 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1817 spontaneous reboots) or a non-working video driver.
2e5d9c85 1818
1819 If unsure, say Y.
1820
46cf98cd
VP
1821config ARCH_USES_PG_UNCACHED
1822 def_bool y
1823 depends on X86_PAT
1824
628c6246
PA
1825config ARCH_RANDOM
1826 def_bool y
1827 prompt "x86 architectural random number generator" if EXPERT
1828 ---help---
1829 Enable the x86 architectural RDRAND instruction
1830 (Intel Bull Mountain technology) to generate random numbers.
1831 If supported, this is a high bandwidth, cryptographically
1832 secure hardware random number generator.
1833
51ae4a2d
PA
1834config X86_SMAP
1835 def_bool y
1836 prompt "Supervisor Mode Access Prevention" if EXPERT
1837 ---help---
1838 Supervisor Mode Access Prevention (SMAP) is a security
1839 feature in newer Intel processors. There is a small
1840 performance cost if this enabled and turned on; there is
1841 also a small increase in the kernel size if this is enabled.
1842
1843 If unsure, say Y.
1844
aa35f896 1845config X86_INTEL_UMIP
796ebc81 1846 def_bool y
aa35f896
RN
1847 depends on CPU_SUP_INTEL
1848 prompt "Intel User Mode Instruction Prevention" if EXPERT
1849 ---help---
1850 The User Mode Instruction Prevention (UMIP) is a security
1851 feature in newer Intel processors. If enabled, a general
796ebc81
RN
1852 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1853 or STR instructions are executed in user mode. These instructions
1854 unnecessarily expose information about the hardware state.
1855
1856 The vast majority of applications do not use these instructions.
1857 For the very few that do, software emulation is provided in
1858 specific cases in protected and virtual-8086 modes. Emulated
1859 results are dummy.
aa35f896 1860
72e9b5fe
DH
1861config X86_INTEL_MPX
1862 prompt "Intel MPX (Memory Protection Extensions)"
1863 def_bool n
df3735c5
RR
1864 # Note: only available in 64-bit mode due to VMA flags shortage
1865 depends on CPU_SUP_INTEL && X86_64
1866 select ARCH_USES_HIGH_VMA_FLAGS
72e9b5fe
DH
1867 ---help---
1868 MPX provides hardware features that can be used in
1869 conjunction with compiler-instrumented code to check
1870 memory references. It is designed to detect buffer
1871 overflow or underflow bugs.
1872
1873 This option enables running applications which are
1874 instrumented or otherwise use MPX. It does not use MPX
1875 itself inside the kernel or to protect the kernel
1876 against bad memory references.
1877
1878 Enabling this option will make the kernel larger:
1879 ~8k of kernel text and 36 bytes of data on a 64-bit
1880 defconfig. It adds a long to the 'mm_struct' which
1881 will increase the kernel memory overhead of each
1882 process and adds some branches to paths used during
1883 exec() and munmap().
1884
1885 For details, see Documentation/x86/intel_mpx.txt
1886
1887 If unsure, say N.
1888
35e97790 1889config X86_INTEL_MEMORY_PROTECTION_KEYS
284244a9 1890 prompt "Intel Memory Protection Keys"
35e97790 1891 def_bool y
284244a9 1892 # Note: only available in 64-bit mode
35e97790 1893 depends on CPU_SUP_INTEL && X86_64
52c8e601
IM
1894 select ARCH_USES_HIGH_VMA_FLAGS
1895 select ARCH_HAS_PKEYS
284244a9
DH
1896 ---help---
1897 Memory Protection Keys provides a mechanism for enforcing
1898 page-based protections, but without requiring modification of the
1899 page tables when an application changes protection domains.
1900
1901 For details, see Documentation/x86/protection-keys.txt
1902
1903 If unsure, say y.
35e97790 1904
506f1d07 1905config EFI
9ba16087 1906 bool "EFI runtime service support"
5b83683f 1907 depends on ACPI
f6ce5002 1908 select UCS2_STRING
022ee6c5 1909 select EFI_RUNTIME_WRAPPERS
506f1d07 1910 ---help---
8f9ca475
IM
1911 This enables the kernel to use EFI runtime services that are
1912 available (such as the EFI variable services).
506f1d07 1913
8f9ca475
IM
1914 This option is only useful on systems that have EFI firmware.
1915 In addition, you should use the latest ELILO loader available
1916 at <http://elilo.sourceforge.net> in order to take advantage
1917 of EFI runtime services. However, even with this option, the
1918 resultant kernel should continue to boot on existing non-EFI
1919 platforms.
506f1d07 1920
291f3632
MF
1921config EFI_STUB
1922 bool "EFI stub support"
b16d8c23 1923 depends on EFI && !X86_USE_3DNOW
7b2a583a 1924 select RELOCATABLE
291f3632
MF
1925 ---help---
1926 This kernel feature allows a bzImage to be loaded directly
1927 by EFI firmware without the use of a bootloader.
1928
4172fe2f 1929 See Documentation/efi-stub.txt for more information.
0c759662 1930
7d453eee
MF
1931config EFI_MIXED
1932 bool "EFI mixed-mode support"
1933 depends on EFI_STUB && X86_64
1934 ---help---
1935 Enabling this feature allows a 64-bit kernel to be booted
1936 on a 32-bit firmware, provided that your CPU supports 64-bit
1937 mode.
1938
1939 Note that it is not possible to boot a mixed-mode enabled
1940 kernel via the EFI boot stub - a bootloader that supports
1941 the EFI handover protocol must be used.
1942
1943 If unsure, say N.
1944
506f1d07 1945config SECCOMP
3c2362e6
HH
1946 def_bool y
1947 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1948 ---help---
506f1d07
SR
1949 This kernel feature is useful for number crunching applications
1950 that may need to compute untrusted bytecode during their
1951 execution. By using pipes or other transports made available to
1952 the process as file descriptors supporting the read/write
1953 syscalls, it's possible to isolate those applications in
1954 their own address space using seccomp. Once seccomp is
9c0bbee8 1955 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1956 and the task is only allowed to execute a few safe syscalls
1957 defined by each seccomp mode.
1958
1959 If unsure, say Y. Only embedded should say N here.
1960
506f1d07
SR
1961source kernel/Kconfig.hz
1962
1963config KEXEC
1964 bool "kexec system call"
2965faa5 1965 select KEXEC_CORE
8f9ca475 1966 ---help---
506f1d07
SR
1967 kexec is a system call that implements the ability to shutdown your
1968 current kernel, and to start another kernel. It is like a reboot
1969 but it is independent of the system firmware. And like a reboot
1970 you can start any kernel with it, not just Linux.
1971
1972 The name comes from the similarity to the exec system call.
1973
1974 It is an ongoing process to be certain the hardware in a machine
1975 is properly shutdown, so do not be surprised if this code does not
bf220695
GU
1976 initially work for you. As of this writing the exact hardware
1977 interface is strongly in flux, so no good recommendation can be
1978 made.
506f1d07 1979
74ca317c
VG
1980config KEXEC_FILE
1981 bool "kexec file based system call"
2965faa5 1982 select KEXEC_CORE
74ca317c 1983 select BUILD_BIN2C
74ca317c
VG
1984 depends on X86_64
1985 depends on CRYPTO=y
1986 depends on CRYPTO_SHA256=y
1987 ---help---
1988 This is new version of kexec system call. This system call is
1989 file based and takes file descriptors as system call argument
1990 for kernel and initramfs as opposed to list of segments as
1991 accepted by previous system call.
1992
b799a09f
AT
1993config ARCH_HAS_KEXEC_PURGATORY
1994 def_bool KEXEC_FILE
1995
8e7d8381
VG
1996config KEXEC_VERIFY_SIG
1997 bool "Verify kernel signature during kexec_file_load() syscall"
74ca317c 1998 depends on KEXEC_FILE
8e7d8381
VG
1999 ---help---
2000 This option makes kernel signature verification mandatory for
d8eb8940
BP
2001 the kexec_file_load() syscall.
2002
2003 In addition to that option, you need to enable signature
2004 verification for the corresponding kernel image type being
2005 loaded in order for this to work.
8e7d8381
VG
2006
2007config KEXEC_BZIMAGE_VERIFY_SIG
2008 bool "Enable bzImage signature verification support"
2009 depends on KEXEC_VERIFY_SIG
2010 depends on SIGNED_PE_FILE_VERIFICATION
2011 select SYSTEM_TRUSTED_KEYRING
2012 ---help---
2013 Enable bzImage signature verification support.
2014
506f1d07 2015config CRASH_DUMP
04b69447 2016 bool "kernel crash dumps"
506f1d07 2017 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 2018 ---help---
506f1d07
SR
2019 Generate crash dump after being started by kexec.
2020 This should be normally only set in special crash dump kernels
2021 which are loaded in the main kernel with kexec-tools into
2022 a specially reserved region and then later executed after
2023 a crash by kdump/kexec. The crash dump kernel must be compiled
2024 to a memory address not used by the main kernel or BIOS using
2025 PHYSICAL_START, or it must be built as a relocatable image
2026 (CONFIG_RELOCATABLE=y).
2027 For more details see Documentation/kdump/kdump.txt
2028
3ab83521 2029config KEXEC_JUMP
6ea30386 2030 bool "kexec jump"
fee7b0d8 2031 depends on KEXEC && HIBERNATION
8f9ca475 2032 ---help---
89081d17
HY
2033 Jump between original kernel and kexeced kernel and invoke
2034 code in physical address mode via KEXEC
3ab83521 2035
506f1d07 2036config PHYSICAL_START
6a108a14 2037 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
ceefccc9 2038 default "0x1000000"
8f9ca475 2039 ---help---
506f1d07
SR
2040 This gives the physical address where the kernel is loaded.
2041
2042 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2043 bzImage will decompress itself to above physical address and
2044 run from there. Otherwise, bzImage will run from the address where
2045 it has been loaded by the boot loader and will ignore above physical
2046 address.
2047
2048 In normal kdump cases one does not have to set/change this option
2049 as now bzImage can be compiled as a completely relocatable image
2050 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2051 address. This option is mainly useful for the folks who don't want
2052 to use a bzImage for capturing the crash dump and want to use a
2053 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2054 to be specifically compiled to run from a specific memory area
2055 (normally a reserved region) and this option comes handy.
2056
ceefccc9
PA
2057 So if you are using bzImage for capturing the crash dump,
2058 leave the value here unchanged to 0x1000000 and set
2059 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2060 for capturing the crash dump change this value to start of
2061 the reserved region. In other words, it can be set based on
2062 the "X" value as specified in the "crashkernel=YM@XM"
2063 command line boot parameter passed to the panic-ed
2064 kernel. Please take a look at Documentation/kdump/kdump.txt
2065 for more details about crash dumps.
506f1d07
SR
2066
2067 Usage of bzImage for capturing the crash dump is recommended as
2068 one does not have to build two kernels. Same kernel can be used
2069 as production kernel and capture kernel. Above option should have
2070 gone away after relocatable bzImage support is introduced. But it
2071 is present because there are users out there who continue to use
2072 vmlinux for dump capture. This option should go away down the
2073 line.
2074
2075 Don't change this unless you know what you are doing.
2076
2077config RELOCATABLE
26717808
PA
2078 bool "Build a relocatable kernel"
2079 default y
8f9ca475 2080 ---help---
506f1d07
SR
2081 This builds a kernel image that retains relocation information
2082 so it can be loaded someplace besides the default 1MB.
2083 The relocations tend to make the kernel binary about 10% larger,
2084 but are discarded at runtime.
2085
2086 One use is for the kexec on panic case where the recovery kernel
2087 must live at a different physical address than the primary
2088 kernel.
2089
2090 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2091 it has been loaded at and the compile time physical address
8ab3820f 2092 (CONFIG_PHYSICAL_START) is used as the minimum location.
506f1d07 2093
8ab3820f 2094config RANDOMIZE_BASE
e8581e3d 2095 bool "Randomize the address of the kernel image (KASLR)"
8ab3820f 2096 depends on RELOCATABLE
6807c846 2097 default y
8ab3820f 2098 ---help---
e8581e3d
BH
2099 In support of Kernel Address Space Layout Randomization (KASLR),
2100 this randomizes the physical address at which the kernel image
2101 is decompressed and the virtual address where the kernel
2102 image is mapped, as a security feature that deters exploit
2103 attempts relying on knowledge of the location of kernel
2104 code internals.
2105
ed9f007e
KC
2106 On 64-bit, the kernel physical and virtual addresses are
2107 randomized separately. The physical address will be anywhere
2108 between 16MB and the top of physical memory (up to 64TB). The
2109 virtual address will be randomized from 16MB up to 1GB (9 bits
2110 of entropy). Note that this also reduces the memory space
2111 available to kernel modules from 1.5GB to 1GB.
2112
2113 On 32-bit, the kernel physical and virtual addresses are
2114 randomized together. They will be randomized from 16MB up to
2115 512MB (8 bits of entropy).
e8581e3d
BH
2116
2117 Entropy is generated using the RDRAND instruction if it is
2118 supported. If RDTSC is supported, its value is mixed into
2119 the entropy pool as well. If neither RDRAND nor RDTSC are
ed9f007e
KC
2120 supported, then entropy is read from the i8254 timer. The
2121 usable entropy is limited by the kernel being built using
2122 2GB addressing, and that PHYSICAL_ALIGN must be at a
2123 minimum of 2MB. As a result, only 10 bits of entropy are
2124 theoretically possible, but the implementations are further
2125 limited due to memory layouts.
e8581e3d 2126
6807c846 2127 If unsure, say Y.
8ab3820f
KC
2128
2129# Relocation on x86 needs some additional build support
845adf72
PA
2130config X86_NEED_RELOCS
2131 def_bool y
8ab3820f 2132 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
845adf72 2133
506f1d07 2134config PHYSICAL_ALIGN
a0215061 2135 hex "Alignment value to which kernel should be aligned"
8ab3820f 2136 default "0x200000"
a0215061
KC
2137 range 0x2000 0x1000000 if X86_32
2138 range 0x200000 0x1000000 if X86_64
8f9ca475 2139 ---help---
506f1d07
SR
2140 This value puts the alignment restrictions on physical address
2141 where kernel is loaded and run from. Kernel is compiled for an
2142 address which meets above alignment restriction.
2143
2144 If bootloader loads the kernel at a non-aligned address and
2145 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2146 address aligned to above value and run from there.
2147
2148 If bootloader loads the kernel at a non-aligned address and
2149 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2150 load address and decompress itself to the address it has been
2151 compiled for and run from there. The address for which kernel is
2152 compiled already meets above alignment restrictions. Hence the
2153 end result is that kernel runs from a physical address meeting
2154 above alignment restrictions.
2155
a0215061
KC
2156 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2157 this value must be a multiple of 0x200000.
2158
506f1d07
SR
2159 Don't change this unless you know what you are doing.
2160
eedb92ab
KS
2161config DYNAMIC_MEMORY_LAYOUT
2162 bool
2163 ---help---
2164 This option makes base addresses of vmalloc and vmemmap as well as
2165 __PAGE_OFFSET movable during boot.
2166
0483e1fa
TG
2167config RANDOMIZE_MEMORY
2168 bool "Randomize the kernel memory sections"
2169 depends on X86_64
2170 depends on RANDOMIZE_BASE
eedb92ab 2171 select DYNAMIC_MEMORY_LAYOUT
0483e1fa
TG
2172 default RANDOMIZE_BASE
2173 ---help---
2174 Randomizes the base virtual address of kernel memory sections
2175 (physical memory mapping, vmalloc & vmemmap). This security feature
2176 makes exploits relying on predictable memory locations less reliable.
2177
2178 The order of allocations remains unchanged. Entropy is generated in
2179 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2180 configuration have in average 30,000 different possible virtual
2181 addresses for each memory section.
2182
6807c846 2183 If unsure, say Y.
0483e1fa 2184
90397a41
TG
2185config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2186 hex "Physical memory mapping padding" if EXPERT
2187 depends on RANDOMIZE_MEMORY
2188 default "0xa" if MEMORY_HOTPLUG
2189 default "0x0"
2190 range 0x1 0x40 if MEMORY_HOTPLUG
2191 range 0x0 0x40
2192 ---help---
2193 Define the padding in terabytes added to the existing physical
2194 memory size during kernel memory randomization. It is useful
2195 for memory hotplug support but reduces the entropy available for
2196 address randomization.
2197
2198 If unsure, leave at the default value.
2199
506f1d07 2200config HOTPLUG_CPU
7c13e6a3 2201 bool "Support for hot-pluggable CPUs"
40b31360 2202 depends on SMP
506f1d07 2203 ---help---
7c13e6a3
DS
2204 Say Y here to allow turning CPUs off and on. CPUs can be
2205 controlled through /sys/devices/system/cpu.
2206 ( Note: power management support will enable this option
2207 automatically on SMP systems. )
2208 Say N if you want to disable CPU hotplug.
506f1d07 2209
80aa1dff
FY
2210config BOOTPARAM_HOTPLUG_CPU0
2211 bool "Set default setting of cpu0_hotpluggable"
2212 default n
2c922cd0 2213 depends on HOTPLUG_CPU
80aa1dff
FY
2214 ---help---
2215 Set whether default state of cpu0_hotpluggable is on or off.
2216
2217 Say Y here to enable CPU0 hotplug by default. If this switch
2218 is turned on, there is no need to give cpu0_hotplug kernel
2219 parameter and the CPU0 hotplug feature is enabled by default.
2220
2221 Please note: there are two known CPU0 dependencies if you want
2222 to enable the CPU0 hotplug feature either by this switch or by
2223 cpu0_hotplug kernel parameter.
2224
2225 First, resume from hibernate or suspend always starts from CPU0.
2226 So hibernate and suspend are prevented if CPU0 is offline.
2227
2228 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2229 offline if any interrupt can not migrate out of CPU0. There may
2230 be other CPU0 dependencies.
2231
2232 Please make sure the dependencies are under your control before
2233 you enable this feature.
2234
2235 Say N if you don't want to enable CPU0 hotplug feature by default.
2236 You still can enable the CPU0 hotplug feature at boot by kernel
2237 parameter cpu0_hotplug.
2238
a71c8bc5
FY
2239config DEBUG_HOTPLUG_CPU0
2240 def_bool n
2241 prompt "Debug CPU0 hotplug"
2c922cd0 2242 depends on HOTPLUG_CPU
a71c8bc5
FY
2243 ---help---
2244 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2245 soon as possible and boots up userspace with CPU0 offlined. User
2246 can online CPU0 back after boot time.
2247
2248 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2249 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2250 compilation or giving cpu0_hotplug kernel parameter at boot.
2251
2252 If unsure, say N.
2253
506f1d07 2254config COMPAT_VDSO
b0b49f26
AL
2255 def_bool n
2256 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
953fee1d 2257 depends on COMPAT_32
8f9ca475 2258 ---help---
b0b49f26
AL
2259 Certain buggy versions of glibc will crash if they are
2260 presented with a 32-bit vDSO that is not mapped at the address
2261 indicated in its segment table.
e84446de 2262
b0b49f26
AL
2263 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2264 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2265 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2266 the only released version with the bug, but OpenSUSE 9
2267 contains a buggy "glibc 2.3.2".
506f1d07 2268
b0b49f26
AL
2269 The symptom of the bug is that everything crashes on startup, saying:
2270 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2271
2272 Saying Y here changes the default value of the vdso32 boot
2273 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2274 This works around the glibc bug but hurts performance.
2275
2276 If unsure, say N: if you are compiling your own kernel, you
2277 are unlikely to be using a buggy version of glibc.
506f1d07 2278
3dc33bd3
KC
2279choice
2280 prompt "vsyscall table for legacy applications"
2281 depends on X86_64
2282 default LEGACY_VSYSCALL_EMULATE
2283 help
2284 Legacy user code that does not know how to find the vDSO expects
2285 to be able to issue three syscalls by calling fixed addresses in
2286 kernel space. Since this location is not randomized with ASLR,
2287 it can be used to assist security vulnerability exploitation.
2288
2289 This setting can be changed at boot time via the kernel command
076ca272 2290 line parameter vsyscall=[emulate|none].
3dc33bd3
KC
2291
2292 On a system with recent enough glibc (2.14 or newer) and no
2293 static binaries, you can say None without a performance penalty
2294 to improve security.
2295
2296 If unsure, select "Emulate".
2297
3dc33bd3
KC
2298 config LEGACY_VSYSCALL_EMULATE
2299 bool "Emulate"
2300 help
2301 The kernel traps and emulates calls into the fixed
2302 vsyscall address mapping. This makes the mapping
2303 non-executable, but it still contains known contents,
2304 which could be used in certain rare security vulnerability
2305 exploits. This configuration is recommended when userspace
2306 still uses the vsyscall area.
2307
2308 config LEGACY_VSYSCALL_NONE
2309 bool "None"
2310 help
2311 There will be no vsyscall mapping at all. This will
2312 eliminate any risk of ASLR bypass due to the vsyscall
2313 fixed address mapping. Attempts to use the vsyscalls
2314 will be reported to dmesg, so that either old or
2315 malicious userspace programs can be identified.
2316
2317endchoice
2318
516cbf37
TB
2319config CMDLINE_BOOL
2320 bool "Built-in kernel command line"
8f9ca475 2321 ---help---
516cbf37
TB
2322 Allow for specifying boot arguments to the kernel at
2323 build time. On some systems (e.g. embedded ones), it is
2324 necessary or convenient to provide some or all of the
2325 kernel boot arguments with the kernel itself (that is,
2326 to not rely on the boot loader to provide them.)
2327
2328 To compile command line arguments into the kernel,
2329 set this option to 'Y', then fill in the
69711ca1 2330 boot arguments in CONFIG_CMDLINE.
516cbf37
TB
2331
2332 Systems with fully functional boot loaders (i.e. non-embedded)
2333 should leave this option set to 'N'.
2334
2335config CMDLINE
2336 string "Built-in kernel command string"
2337 depends on CMDLINE_BOOL
2338 default ""
8f9ca475 2339 ---help---
516cbf37
TB
2340 Enter arguments here that should be compiled into the kernel
2341 image and used at boot time. If the boot loader provides a
2342 command line at boot time, it is appended to this string to
2343 form the full kernel command line, when the system boots.
2344
2345 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2346 change this behavior.
2347
2348 In most cases, the command line (whether built-in or provided
2349 by the boot loader) should specify the device for the root
2350 file system.
2351
2352config CMDLINE_OVERRIDE
2353 bool "Built-in command line overrides boot loader arguments"
516cbf37 2354 depends on CMDLINE_BOOL
8f9ca475 2355 ---help---
516cbf37
TB
2356 Set this option to 'Y' to have the kernel ignore the boot loader
2357 command line, and use ONLY the built-in command line.
2358
2359 This is used to work around broken boot loaders. This should
2360 be set to 'N' under normal conditions.
2361
a5b9e5a2
AL
2362config MODIFY_LDT_SYSCALL
2363 bool "Enable the LDT (local descriptor table)" if EXPERT
2364 default y
2365 ---help---
2366 Linux can allow user programs to install a per-process x86
2367 Local Descriptor Table (LDT) using the modify_ldt(2) system
2368 call. This is required to run 16-bit or segmented code such as
2369 DOSEMU or some Wine programs. It is also used by some very old
2370 threading libraries.
2371
2372 Enabling this feature adds a small amount of overhead to
2373 context switches and increases the low-level kernel attack
2374 surface. Disabling it removes the modify_ldt(2) system call.
2375
2376 Saying 'N' here may make sense for embedded or server kernels.
2377
b700e7f0
SJ
2378source "kernel/livepatch/Kconfig"
2379
506f1d07
SR
2380endmenu
2381
3072e413
MH
2382config ARCH_HAS_ADD_PAGES
2383 def_bool y
2384 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2385
506f1d07
SR
2386config ARCH_ENABLE_MEMORY_HOTPLUG
2387 def_bool y
2388 depends on X86_64 || (X86_32 && HIGHMEM)
2389
35551053
GH
2390config ARCH_ENABLE_MEMORY_HOTREMOVE
2391 def_bool y
2392 depends on MEMORY_HOTPLUG
2393
e534c7c5 2394config USE_PERCPU_NUMA_NODE_ID
645a7919 2395 def_bool y
e534c7c5
LS
2396 depends on NUMA
2397
9491846f
KS
2398config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2399 def_bool y
2400 depends on X86_64 || X86_PAE
2401
c177c81e
NH
2402config ARCH_ENABLE_HUGEPAGE_MIGRATION
2403 def_bool y
2404 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2405
9c670ea3
NH
2406config ARCH_ENABLE_THP_MIGRATION
2407 def_bool y
2408 depends on X86_64 && TRANSPARENT_HUGEPAGE
2409
da85f865 2410menu "Power management and ACPI options"
e279b6c1
SR
2411
2412config ARCH_HIBERNATION_HEADER
3c2362e6 2413 def_bool y
e279b6c1 2414 depends on X86_64 && HIBERNATION
e279b6c1
SR
2415
2416source "kernel/power/Kconfig"
2417
2418source "drivers/acpi/Kconfig"
2419
efafc8b2
FT
2420source "drivers/sfi/Kconfig"
2421
a6b68076 2422config X86_APM_BOOT
6fc108a0 2423 def_bool y
282e5aab 2424 depends on APM
a6b68076 2425
e279b6c1
SR
2426menuconfig APM
2427 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 2428 depends on X86_32 && PM_SLEEP
e279b6c1
SR
2429 ---help---
2430 APM is a BIOS specification for saving power using several different
2431 techniques. This is mostly useful for battery powered laptops with
2432 APM compliant BIOSes. If you say Y here, the system time will be
2433 reset after a RESUME operation, the /proc/apm device will provide
2434 battery status information, and user-space programs will receive
2435 notification of APM "events" (e.g. battery status change).
2436
2437 If you select "Y" here, you can disable actual use of the APM
2438 BIOS by passing the "apm=off" option to the kernel at boot time.
2439
2440 Note that the APM support is almost completely disabled for
2441 machines with more than one CPU.
2442
2443 In order to use APM, you will need supporting software. For location
2dc98fd3
MW
2444 and more information, read <file:Documentation/power/apm-acpi.txt>
2445 and the Battery Powered Linux mini-HOWTO, available from
e279b6c1
SR
2446 <http://www.tldp.org/docs.html#howto>.
2447
2448 This driver does not spin down disk drives (see the hdparm(8)
2449 manpage ("man 8 hdparm") for that), and it doesn't turn off
2450 VESA-compliant "green" monitors.
2451
2452 This driver does not support the TI 4000M TravelMate and the ACER
2453 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2454 desktop machines also don't have compliant BIOSes, and this driver
2455 may cause those machines to panic during the boot phase.
2456
2457 Generally, if you don't have a battery in your machine, there isn't
2458 much point in using this driver and you should say N. If you get
2459 random kernel OOPSes or reboots that don't seem to be related to
2460 anything, try disabling/enabling this option (or disabling/enabling
2461 APM in your BIOS).
2462
2463 Some other things you should try when experiencing seemingly random,
2464 "weird" problems:
2465
2466 1) make sure that you have enough swap space and that it is
2467 enabled.
2468 2) pass the "no-hlt" option to the kernel
2469 3) switch on floating point emulation in the kernel and pass
2470 the "no387" option to the kernel
2471 4) pass the "floppy=nodma" option to the kernel
2472 5) pass the "mem=4M" option to the kernel (thereby disabling
2473 all but the first 4 MB of RAM)
2474 6) make sure that the CPU is not over clocked.
2475 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2476 8) disable the cache from your BIOS settings
2477 9) install a fan for the video card or exchange video RAM
2478 10) install a better fan for the CPU
2479 11) exchange RAM chips
2480 12) exchange the motherboard.
2481
2482 To compile this driver as a module, choose M here: the
2483 module will be called apm.
2484
2485if APM
2486
2487config APM_IGNORE_USER_SUSPEND
2488 bool "Ignore USER SUSPEND"
8f9ca475 2489 ---help---
e279b6c1
SR
2490 This option will ignore USER SUSPEND requests. On machines with a
2491 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2492 series notebooks, it is necessary to say Y because of a BIOS bug.
2493
2494config APM_DO_ENABLE
2495 bool "Enable PM at boot time"
2496 ---help---
2497 Enable APM features at boot time. From page 36 of the APM BIOS
2498 specification: "When disabled, the APM BIOS does not automatically
2499 power manage devices, enter the Standby State, enter the Suspend
2500 State, or take power saving steps in response to CPU Idle calls."
2501 This driver will make CPU Idle calls when Linux is idle (unless this
2502 feature is turned off -- see "Do CPU IDLE calls", below). This
2503 should always save battery power, but more complicated APM features
2504 will be dependent on your BIOS implementation. You may need to turn
2505 this option off if your computer hangs at boot time when using APM
2506 support, or if it beeps continuously instead of suspending. Turn
2507 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2508 T400CDT. This is off by default since most machines do fine without
2509 this feature.
2510
2511config APM_CPU_IDLE
dd8af076 2512 depends on CPU_IDLE
e279b6c1 2513 bool "Make CPU Idle calls when idle"
8f9ca475 2514 ---help---
e279b6c1
SR
2515 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2516 On some machines, this can activate improved power savings, such as
2517 a slowed CPU clock rate, when the machine is idle. These idle calls
2518 are made after the idle loop has run for some length of time (e.g.,
2519 333 mS). On some machines, this will cause a hang at boot time or
2520 whenever the CPU becomes idle. (On machines with more than one CPU,
2521 this option does nothing.)
2522
2523config APM_DISPLAY_BLANK
2524 bool "Enable console blanking using APM"
8f9ca475 2525 ---help---
e279b6c1
SR
2526 Enable console blanking using the APM. Some laptops can use this to
2527 turn off the LCD backlight when the screen blanker of the Linux
2528 virtual console blanks the screen. Note that this is only used by
2529 the virtual console screen blanker, and won't turn off the backlight
2530 when using the X Window system. This also doesn't have anything to
2531 do with your VESA-compliant power-saving monitor. Further, this
2532 option doesn't work for all laptops -- it might not turn off your
2533 backlight at all, or it might print a lot of errors to the console,
2534 especially if you are using gpm.
2535
2536config APM_ALLOW_INTS
2537 bool "Allow interrupts during APM BIOS calls"
8f9ca475 2538 ---help---
e279b6c1
SR
2539 Normally we disable external interrupts while we are making calls to
2540 the APM BIOS as a measure to lessen the effects of a badly behaving
2541 BIOS implementation. The BIOS should reenable interrupts if it
2542 needs to. Unfortunately, some BIOSes do not -- especially those in
2543 many of the newer IBM Thinkpads. If you experience hangs when you
2544 suspend, try setting this to Y. Otherwise, say N.
2545
e279b6c1
SR
2546endif # APM
2547
bb0a56ec 2548source "drivers/cpufreq/Kconfig"
e279b6c1
SR
2549
2550source "drivers/cpuidle/Kconfig"
2551
27471fdb
AH
2552source "drivers/idle/Kconfig"
2553
e279b6c1
SR
2554endmenu
2555
2556
2557menu "Bus options (PCI etc.)"
2558
2559config PCI
1ac97018 2560 bool "PCI support"
1c858087 2561 default y
8f9ca475 2562 ---help---
e279b6c1
SR
2563 Find out whether you have a PCI motherboard. PCI is the name of a
2564 bus system, i.e. the way the CPU talks to the other stuff inside
2565 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2566 VESA. If you have PCI, say Y, otherwise N.
2567
e279b6c1
SR
2568choice
2569 prompt "PCI access mode"
efefa6f6 2570 depends on X86_32 && PCI
e279b6c1
SR
2571 default PCI_GOANY
2572 ---help---
2573 On PCI systems, the BIOS can be used to detect the PCI devices and
2574 determine their configuration. However, some old PCI motherboards
2575 have BIOS bugs and may crash if this is done. Also, some embedded
2576 PCI-based systems don't have any BIOS at all. Linux can also try to
2577 detect the PCI hardware directly without using the BIOS.
2578
2579 With this option, you can specify how Linux should detect the
2580 PCI devices. If you choose "BIOS", the BIOS will be used,
2581 if you choose "Direct", the BIOS won't be used, and if you
2582 choose "MMConfig", then PCI Express MMCONFIG will be used.
2583 If you choose "Any", the kernel will try MMCONFIG, then the
2584 direct access method and falls back to the BIOS if that doesn't
2585 work. If unsure, go with the default, which is "Any".
2586
2587config PCI_GOBIOS
2588 bool "BIOS"
2589
2590config PCI_GOMMCONFIG
2591 bool "MMConfig"
2592
2593config PCI_GODIRECT
2594 bool "Direct"
2595
3ef0e1f8 2596config PCI_GOOLPC
76fb6570 2597 bool "OLPC XO-1"
3ef0e1f8
AS
2598 depends on OLPC
2599
2bdd1b03
AS
2600config PCI_GOANY
2601 bool "Any"
2602
e279b6c1
SR
2603endchoice
2604
2605config PCI_BIOS
3c2362e6 2606 def_bool y
efefa6f6 2607 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
e279b6c1
SR
2608
2609# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2610config PCI_DIRECT
3c2362e6 2611 def_bool y
0aba496f 2612 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
e279b6c1
SR
2613
2614config PCI_MMCONFIG
b45c9f36
JK
2615 bool "Support mmconfig PCI config space access" if X86_64
2616 default y
8364e1f8 2617 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
b45c9f36 2618 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
e279b6c1 2619
3ef0e1f8 2620config PCI_OLPC
2bdd1b03
AS
2621 def_bool y
2622 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 2623
b5401a96
AN
2624config PCI_XEN
2625 def_bool y
2626 depends on PCI && XEN
2627 select SWIOTLB_XEN
2628
e279b6c1 2629config PCI_DOMAINS
3c2362e6 2630 def_bool y
e279b6c1 2631 depends on PCI
e279b6c1 2632
8364e1f8
JK
2633config MMCONF_FAM10H
2634 def_bool y
2635 depends on X86_64 && PCI_MMCONFIG && ACPI
e279b6c1 2636
3f6ea84a 2637config PCI_CNB20LE_QUIRK
6a108a14 2638 bool "Read CNB20LE Host Bridge Windows" if EXPERT
6ea30386 2639 depends on PCI
3f6ea84a
IS
2640 help
2641 Read the PCI windows out of the CNB20LE host bridge. This allows
2642 PCI hotplug to work on systems with the CNB20LE chipset which do
2643 not have ACPI.
2644
64a5fed6
BH
2645 There's no public spec for this chipset, and this functionality
2646 is known to be incomplete.
2647
2648 You should say N unless you know you need this.
2649
e279b6c1
SR
2650source "drivers/pci/Kconfig"
2651
3a495511 2652config ISA_BUS
17a2a129 2653 bool "ISA bus support on modern systems" if EXPERT
3a495511 2654 help
17a2a129
WBG
2655 Expose ISA bus device drivers and options available for selection and
2656 configuration. Enable this option if your target machine has an ISA
2657 bus. ISA is an older system, displaced by PCI and newer bus
2658 architectures -- if your target machine is modern, it probably does
2659 not have an ISA bus.
3a495511
WBG
2660
2661 If unsure, say N.
2662
1c00f016 2663# x86_64 have no ISA slots, but can have ISA-style DMA.
e279b6c1 2664config ISA_DMA_API
1c00f016
DR
2665 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2666 default y
2667 help
2668 Enables ISA-style DMA support for devices requiring such controllers.
2669 If unsure, say Y.
e279b6c1 2670
51e68d05
LT
2671if X86_32
2672
e279b6c1
SR
2673config ISA
2674 bool "ISA support"
8f9ca475 2675 ---help---
e279b6c1
SR
2676 Find out whether you have ISA slots on your motherboard. ISA is the
2677 name of a bus system, i.e. the way the CPU talks to the other stuff
2678 inside your box. Other bus systems are PCI, EISA, MicroChannel
2679 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2680 newer boards don't support it. If you have ISA, say Y, otherwise N.
2681
2682config EISA
2683 bool "EISA support"
2684 depends on ISA
2685 ---help---
2686 The Extended Industry Standard Architecture (EISA) bus was
2687 developed as an open alternative to the IBM MicroChannel bus.
2688
2689 The EISA bus provided some of the features of the IBM MicroChannel
2690 bus while maintaining backward compatibility with cards made for
2691 the older ISA bus. The EISA bus saw limited use between 1988 and
2692 1995 when it was made obsolete by the PCI bus.
2693
2694 Say Y here if you are building a kernel for an EISA-based machine.
2695
2696 Otherwise, say N.
2697
2698source "drivers/eisa/Kconfig"
2699
e279b6c1
SR
2700config SCx200
2701 tristate "NatSemi SCx200 support"
8f9ca475 2702 ---help---
e279b6c1
SR
2703 This provides basic support for National Semiconductor's
2704 (now AMD's) Geode processors. The driver probes for the
2705 PCI-IDs of several on-chip devices, so its a good dependency
2706 for other scx200_* drivers.
2707
2708 If compiled as a module, the driver is named scx200.
2709
2710config SCx200HR_TIMER
2711 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
592913ec 2712 depends on SCx200
e279b6c1 2713 default y
8f9ca475 2714 ---help---
e279b6c1
SR
2715 This driver provides a clocksource built upon the on-chip
2716 27MHz high-resolution timer. Its also a workaround for
2717 NSC Geode SC-1100's buggy TSC, which loses time when the
2718 processor goes idle (as is done by the scheduler). The
2719 other workaround is idle=poll boot option.
2720
3ef0e1f8
AS
2721config OLPC
2722 bool "One Laptop Per Child support"
54008979 2723 depends on !X86_PAE
3c554946 2724 select GPIOLIB
dc3119e7 2725 select OF
45bb1674 2726 select OF_PROMTREE
b4e51854 2727 select IRQ_DOMAIN
8f9ca475 2728 ---help---
3ef0e1f8
AS
2729 Add support for detecting the unique features of the OLPC
2730 XO hardware.
2731
a3128588
DD
2732config OLPC_XO1_PM
2733 bool "OLPC XO-1 Power Management"
97c4cb71 2734 depends on OLPC && MFD_CS5535 && PM_SLEEP
a3128588 2735 select MFD_CORE
bf1ebf00 2736 ---help---
97c4cb71 2737 Add support for poweroff and suspend of the OLPC XO-1 laptop.
bf1ebf00 2738
cfee9597
DD
2739config OLPC_XO1_RTC
2740 bool "OLPC XO-1 Real Time Clock"
2741 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2742 ---help---
2743 Add support for the XO-1 real time clock, which can be used as a
2744 programmable wakeup source.
2745
7feda8e9
DD
2746config OLPC_XO1_SCI
2747 bool "OLPC XO-1 SCI extras"
92e830f2 2748 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
ed8e47fe 2749 depends on INPUT=y
d8d01a63 2750 select POWER_SUPPLY
7feda8e9
DD
2751 ---help---
2752 Add support for SCI-based features of the OLPC XO-1 laptop:
7bc74b3d 2753 - EC-driven system wakeups
7feda8e9 2754 - Power button
7bc74b3d 2755 - Ebook switch
2cf2baea 2756 - Lid switch
e1040ac6
DD
2757 - AC adapter status updates
2758 - Battery status updates
7feda8e9 2759
a0f30f59
DD
2760config OLPC_XO15_SCI
2761 bool "OLPC XO-1.5 SCI extras"
d8d01a63
DD
2762 depends on OLPC && ACPI
2763 select POWER_SUPPLY
a0f30f59
DD
2764 ---help---
2765 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2766 - EC-driven system wakeups
2767 - AC adapter status updates
2768 - Battery status updates
bf1ebf00 2769
d4f3e350
EW
2770config ALIX
2771 bool "PCEngines ALIX System Support (LED setup)"
2772 select GPIOLIB
2773 ---help---
2774 This option enables system support for the PCEngines ALIX.
2775 At present this just sets up LEDs for GPIO control on
2776 ALIX2/3/6 boards. However, other system specific setup should
2777 get added here.
2778
2779 Note: You must still enable the drivers for GPIO and LED support
2780 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2781
2782 Note: You have to set alix.force=1 for boards with Award BIOS.
2783
da4e3302
PP
2784config NET5501
2785 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2786 select GPIOLIB
2787 ---help---
2788 This option enables system support for the Soekris Engineering net5501.
2789
3197059a
PP
2790config GEOS
2791 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2792 select GPIOLIB
2793 depends on DMI
2794 ---help---
2795 This option enables system support for the Traverse Technologies GEOS.
2796
7d029125
VD
2797config TS5500
2798 bool "Technologic Systems TS-5500 platform support"
2799 depends on MELAN
2800 select CHECK_SIGNATURE
2801 select NEW_LEDS
2802 select LEDS_CLASS
2803 ---help---
2804 This option enables system support for the Technologic Systems TS-5500.
2805
bc0120fd
SR
2806endif # X86_32
2807
23ac4ae8 2808config AMD_NB
e279b6c1 2809 def_bool y
0e152cd7 2810 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2811
2812source "drivers/pcmcia/Kconfig"
2813
388b78ad 2814config RAPIDIO
fdf90abc 2815 tristate "RapidIO support"
388b78ad
AB
2816 depends on PCI
2817 default n
2818 help
fdf90abc 2819 If enabled this option will include drivers and the core
388b78ad
AB
2820 infrastructure code to support RapidIO interconnect devices.
2821
2822source "drivers/rapidio/Kconfig"
2823
e3263ab3
DH
2824config X86_SYSFB
2825 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2826 help
2827 Firmwares often provide initial graphics framebuffers so the BIOS,
2828 bootloader or kernel can show basic video-output during boot for
2829 user-guidance and debugging. Historically, x86 used the VESA BIOS
2830 Extensions and EFI-framebuffers for this, which are mostly limited
2831 to x86.
2832 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2833 framebuffers so the new generic system-framebuffer drivers can be
2834 used on x86. If the framebuffer is not compatible with the generic
2835 modes, it is adverticed as fallback platform framebuffer so legacy
2836 drivers like efifb, vesafb and uvesafb can pick it up.
2837 If this option is not selected, all system framebuffers are always
2838 marked as fallback platform framebuffers as usual.
2839
2840 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2841 not be able to pick up generic system framebuffers if this option
2842 is selected. You are highly encouraged to enable simplefb as
2843 replacement if you select this option. simplefb can correctly deal
2844 with generic system framebuffers. But you should still keep vesafb
2845 and others enabled as fallback if a system framebuffer is
2846 incompatible with simplefb.
2847
2848 If unsure, say Y.
2849
e279b6c1
SR
2850endmenu
2851
2852
2853menu "Executable file formats / Emulations"
2854
2855source "fs/Kconfig.binfmt"
2856
2857config IA32_EMULATION
2858 bool "IA32 Emulation"
2859 depends on X86_64
39f88911 2860 select ARCH_WANT_OLD_COMPAT_IPC
d1603990 2861 select BINFMT_ELF
a97f52e6 2862 select COMPAT_BINFMT_ELF
39f88911 2863 select COMPAT_OLD_SIGACTION
8f9ca475 2864 ---help---
5fd92e65
L
2865 Include code to run legacy 32-bit programs under a
2866 64-bit kernel. You should likely turn this on, unless you're
2867 100% sure that you don't have any 32-bit programs left.
e279b6c1
SR
2868
2869config IA32_AOUT
8f9ca475
IM
2870 tristate "IA32 a.out support"
2871 depends on IA32_EMULATION
2872 ---help---
2873 Support old a.out binaries in the 32bit emulation.
e279b6c1 2874
0bf62763 2875config X86_X32
6ea30386 2876 bool "x32 ABI for 64-bit mode"
9b54050b 2877 depends on X86_64
5fd92e65
L
2878 ---help---
2879 Include code to run binaries for the x32 native 32-bit ABI
2880 for 64-bit processors. An x32 process gets access to the
2881 full 64-bit register file and wide data path while leaving
2882 pointers at 32 bits for smaller memory footprint.
2883
2884 You will need a recent binutils (2.22 or later) with
2885 elf32_x86_64 support enabled to compile a kernel with this
2886 option set.
2887
953fee1d
IM
2888config COMPAT_32
2889 def_bool y
2890 depends on IA32_EMULATION || X86_32
2891 select HAVE_UID16
2892 select OLD_SIGSUSPEND3
2893
e279b6c1 2894config COMPAT
3c2362e6 2895 def_bool y
0bf62763 2896 depends on IA32_EMULATION || X86_X32
e279b6c1 2897
3120e25e 2898if COMPAT
e279b6c1 2899config COMPAT_FOR_U64_ALIGNMENT
3120e25e 2900 def_bool y
e279b6c1
SR
2901
2902config SYSVIPC_COMPAT
3c2362e6 2903 def_bool y
3120e25e 2904 depends on SYSVIPC
3120e25e 2905endif
ee009e4a 2906
e279b6c1
SR
2907endmenu
2908
2909
e5beae16
KP
2910config HAVE_ATOMIC_IOMAP
2911 def_bool y
2912 depends on X86_32
2913
4692d77f
AR
2914config X86_DEV_DMA_OPS
2915 bool
83125a3a 2916 depends on X86_64 || STA2X11
4692d77f 2917
f7219a53
AR
2918config X86_DMA_REMAP
2919 bool
83125a3a 2920 depends on STA2X11
f7219a53 2921
e585513b
KS
2922config HAVE_GENERIC_GUP
2923 def_bool y
2924
e279b6c1
SR
2925source "net/Kconfig"
2926
2927source "drivers/Kconfig"
2928
2929source "drivers/firmware/Kconfig"
2930
2931source "fs/Kconfig"
2932
e279b6c1
SR
2933source "arch/x86/Kconfig.debug"
2934
2935source "security/Kconfig"
2936
2937source "crypto/Kconfig"
2938
edf88417
AK
2939source "arch/x86/kvm/Kconfig"
2940
e279b6c1 2941source "lib/Kconfig"