Merge branches 'acpica', 'acpi-video' and 'acpi-fan'
[deliverable/linux.git] / arch / x86 / Kconfig
CommitLineData
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1# Select 32 or 64 bit
2config 64BIT
6840999b 3 bool "64-bit kernel" if ARCH = "x86"
ffee0de4 4 default ARCH != "i386"
8f9ca475 5 ---help---
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6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9config X86_32
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10 def_bool y
11 depends on !64BIT
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12
13config X86_64
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14 def_bool y
15 depends on 64BIT
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16
17### Arch settings
8d5fffb9 18config X86
3c2362e6 19 def_bool y
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20 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
22 select ANON_INODES
23 select ARCH_CLOCKSOURCE_DATA
24 select ARCH_DISCARD_MEMBLOCK
25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
446f24d1 26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
6471b825 27 select ARCH_HAS_ELF_RANDOMIZE
72d93104 28 select ARCH_HAS_FAST_MULTIPLIER
957e3fac 29 select ARCH_HAS_GCOV_PROFILE_ALL
96601adb 30 select ARCH_HAS_PMEM_API if X86_64
67a3e8fe 31 select ARCH_HAS_MMIO_FLUSH
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32 select ARCH_HAS_SG_CHAIN
33 select ARCH_HAVE_NMI_SAFE_CMPXCHG
34 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
77fbbc81 35 select ARCH_MIGHT_HAVE_PC_PARPORT
5e2c18c0 36 select ARCH_MIGHT_HAVE_PC_SERIO
6471b825 37 select ARCH_SUPPORTS_ATOMIC_RMW
3b242c66 38 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
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39 select ARCH_SUPPORTS_INT128 if X86_64
40 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
41 select ARCH_USE_BUILTIN_BSWAP
42 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
43 select ARCH_USE_QUEUED_RWLOCKS
44 select ARCH_USE_QUEUED_SPINLOCKS
72b252ae 45 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
5aaeb5c0 46 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
da4276b8 47 select ARCH_WANT_FRAME_POINTERS
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48 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
49 select ARCH_WANT_OPTIONAL_GPIOLIB
50 select BUILDTIME_EXTABLE_SORT
51 select CLKEVT_I8253
52 select CLKSRC_I8253 if X86_32
53 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
54 select CLOCKSOURCE_WATCHDOG
55 select CLONE_BACKWARDS if X86_32
56 select COMPAT_OLD_SIGACTION if IA32_EMULATION
57 select DCACHE_WORD_ACCESS
45471cd9
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58 select EDAC_ATOMIC_SCRUB
59 select EDAC_SUPPORT
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60 select GENERIC_CLOCKEVENTS
61 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
62 select GENERIC_CLOCKEVENTS_MIN_ADJUST
63 select GENERIC_CMOS_UPDATE
64 select GENERIC_CPU_AUTOPROBE
5b7c73e0 65 select GENERIC_EARLY_IOREMAP
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66 select GENERIC_FIND_FIRST_BIT
67 select GENERIC_IOMAP
68 select GENERIC_IRQ_PROBE
69 select GENERIC_IRQ_SHOW
70 select GENERIC_PENDING_IRQ if SMP
71 select GENERIC_SMP_IDLE_THREAD
72 select GENERIC_STRNCPY_FROM_USER
73 select GENERIC_STRNLEN_USER
74 select GENERIC_TIME_VSYSCALL
75 select HAVE_ACPI_APEI if ACPI
76 select HAVE_ACPI_APEI_NMI if ACPI
77 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
78 select HAVE_AOUT if X86_32
79 select HAVE_ARCH_AUDITSYSCALL
80 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
81 select HAVE_ARCH_JUMP_LABEL
82 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
83 select HAVE_ARCH_KGDB
84 select HAVE_ARCH_KMEMCHECK
85 select HAVE_ARCH_SECCOMP_FILTER
86 select HAVE_ARCH_SOFT_DIRTY if X86_64
87 select HAVE_ARCH_TRACEHOOK
88 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
89 select HAVE_BPF_JIT if X86_64
90 select HAVE_CC_STACKPROTECTOR
91 select HAVE_CMPXCHG_DOUBLE
92 select HAVE_CMPXCHG_LOCAL
93 select HAVE_CONTEXT_TRACKING if X86_64
c1bd55f9 94 select HAVE_COPY_THREAD_TLS
cf4db259 95 select HAVE_C_RECORDMCOUNT
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96 select HAVE_DEBUG_KMEMLEAK
97 select HAVE_DEBUG_STACKOVERFLOW
98 select HAVE_DMA_API_DEBUG
99 select HAVE_DMA_ATTRS
100 select HAVE_DMA_CONTIGUOUS
677aa9f7 101 select HAVE_DYNAMIC_FTRACE
06aeaaea 102 select HAVE_DYNAMIC_FTRACE_WITH_REGS
58340a07 103 select HAVE_EFFICIENT_UNALIGNED_ACCESS
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104 select HAVE_FENTRY if X86_64
105 select HAVE_FTRACE_MCOUNT_RECORD
106 select HAVE_FUNCTION_GRAPH_FP_TEST
107 select HAVE_FUNCTION_GRAPH_TRACER
108 select HAVE_FUNCTION_TRACER
109 select HAVE_GENERIC_DMA_COHERENT if X86_32
110 select HAVE_HW_BREAKPOINT
111 select HAVE_IDE
112 select HAVE_IOREMAP_PROT
113 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
114 select HAVE_IRQ_TIME_ACCOUNTING
2e9f3bdd 115 select HAVE_KERNEL_BZIP2
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116 select HAVE_KERNEL_GZIP
117 select HAVE_KERNEL_LZ4
2e9f3bdd 118 select HAVE_KERNEL_LZMA
13510997 119 select HAVE_KERNEL_LZO
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120 select HAVE_KERNEL_XZ
121 select HAVE_KPROBES
122 select HAVE_KPROBES_ON_FTRACE
123 select HAVE_KRETPROBES
124 select HAVE_KVM
125 select HAVE_LIVEPATCH if X86_64
126 select HAVE_MEMBLOCK
127 select HAVE_MEMBLOCK_NODE_MAP
0102752e 128 select HAVE_MIXED_BREAKPOINTS_REGS
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129 select HAVE_OPROFILE
130 select HAVE_OPTPROBES
131 select HAVE_PCSPKR_PLATFORM
132 select HAVE_PERF_EVENTS
c01d4323 133 select HAVE_PERF_EVENTS_NMI
c5e63197 134 select HAVE_PERF_REGS
c5ebcedb 135 select HAVE_PERF_USER_STACK_DUMP
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136 select HAVE_REGS_AND_STACK_ACCESS_API
137 select HAVE_SYSCALL_TRACEPOINTS
0c3619ea 138 select HAVE_UID16 if X86_32 || IA32_EMULATION
6471b825 139 select HAVE_UNSTABLE_SCHED_CLOCK
7c68af6e 140 select HAVE_USER_RETURN_NOTIFIER
c0185808 141 select IRQ_FORCED_THREADING
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142 select MODULES_USE_ELF_RELA if X86_64
143 select MODULES_USE_ELF_REL if X86_32
144 select OLD_SIGACTION if X86_32
145 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
146 select PERF_EVENTS
3195ef59 147 select RTC_LIB
6471b825 148 select SPARSE_IRQ
83fe27ea 149 select SRCU
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150 select SYSCTL_EXCEPTION_TRACE
151 select USER_STACKTRACE_SUPPORT
152 select VIRT_TO_BUS
153 select X86_DEV_DMA_OPS if X86_64
154 select X86_FEATURE_NAMES if PROC_FS
7d8330a5 155
ba7e4d13 156config INSTRUCTION_DECODER
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157 def_bool y
158 depends on KPROBES || PERF_EVENTS || UPROBES
ba7e4d13 159
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160config PERF_EVENTS_INTEL_UNCORE
161 def_bool y
ce5686d4 162 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
7fb0f1de 163
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164config OUTPUT_FORMAT
165 string
166 default "elf32-i386" if X86_32
167 default "elf64-x86-64" if X86_64
168
73531905 169config ARCH_DEFCONFIG
b9b39bfb 170 string
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SR
171 default "arch/x86/configs/i386_defconfig" if X86_32
172 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 173
8d5fffb9 174config LOCKDEP_SUPPORT
3c2362e6 175 def_bool y
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176
177config STACKTRACE_SUPPORT
3c2362e6 178 def_bool y
8d5fffb9 179
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180config HAVE_LATENCYTOP_SUPPORT
181 def_bool y
182
8d5fffb9 183config MMU
3c2362e6 184 def_bool y
8d5fffb9 185
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SR
186config SBUS
187 bool
188
3bc4e459 189config NEED_DMA_MAP_STATE
3120e25e 190 def_bool y
a6dfa128 191 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
3bc4e459 192
18e98307 193config NEED_SG_DMA_LENGTH
4a14d84e 194 def_bool y
18e98307 195
8d5fffb9 196config GENERIC_ISA_DMA
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197 def_bool y
198 depends on ISA_DMA_API
8d5fffb9 199
8d5fffb9 200config GENERIC_BUG
3c2362e6 201 def_bool y
8d5fffb9 202 depends on BUG
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203 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
204
205config GENERIC_BUG_RELATIVE_POINTERS
206 bool
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207
208config GENERIC_HWEIGHT
3c2362e6 209 def_bool y
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210
211config ARCH_MAY_HAVE_PC_FDC
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212 def_bool y
213 depends on ISA_DMA_API
8d5fffb9 214
1032c0ba 215config RWSEM_XCHGADD_ALGORITHM
3120e25e 216 def_bool y
1032c0ba 217
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218config GENERIC_CALIBRATE_DELAY
219 def_bool y
220
9a0b8415 221config ARCH_HAS_CPU_RELAX
222 def_bool y
223
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224config ARCH_HAS_CACHE_LINE_SIZE
225 def_bool y
226
dd5af90a 227config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 228 def_bool y
b32ef636 229
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230config NEED_PER_CPU_EMBED_FIRST_CHUNK
231 def_bool y
232
233config NEED_PER_CPU_PAGE_FIRST_CHUNK
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234 def_bool y
235
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236config ARCH_HIBERNATION_POSSIBLE
237 def_bool y
801e4062 238
f4cb5700
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239config ARCH_SUSPEND_POSSIBLE
240 def_bool y
f4cb5700 241
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242config ARCH_WANT_HUGE_PMD_SHARE
243 def_bool y
244
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245config ARCH_WANT_GENERAL_HUGETLB
246 def_bool y
247
8d5fffb9 248config ZONE_DMA32
e0fd24a3 249 def_bool y if X86_64
8d5fffb9 250
8d5fffb9 251config AUDIT_ARCH
e0fd24a3 252 def_bool y if X86_64
8d5fffb9 253
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254config ARCH_SUPPORTS_OPTIMIZED_INLINING
255 def_bool y
256
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257config ARCH_SUPPORTS_DEBUG_PAGEALLOC
258 def_bool y
259
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260config KASAN_SHADOW_OFFSET
261 hex
262 depends on KASAN
263 default 0xdffffc0000000000
264
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265config HAVE_INTEL_TXT
266 def_bool y
6ea30386 267 depends on INTEL_IOMMU && ACPI
69575d38 268
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SR
269config X86_32_SMP
270 def_bool y
271 depends on X86_32 && SMP
272
273config X86_64_SMP
274 def_bool y
275 depends on X86_64 && SMP
276
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TH
277config X86_32_LAZY_GS
278 def_bool y
60a5317f 279 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 280
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281config ARCH_HWEIGHT_CFLAGS
282 string
283 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
284 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
285
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286config ARCH_SUPPORTS_UPROBES
287 def_bool y
288
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289config FIX_EARLYCON_MEM
290 def_bool y
291
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292config PGTABLE_LEVELS
293 int
294 default 4 if X86_64
295 default 3 if X86_PAE
296 default 2
297
506f1d07 298source "init/Kconfig"
dc52ddc0 299source "kernel/Kconfig.freezer"
8d5fffb9 300
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301menu "Processor type and features"
302
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303config ZONE_DMA
304 bool "DMA memory allocation support" if EXPERT
305 default y
306 help
307 DMA memory allocation support allows devices with less than 32-bit
308 addressing to allocate within the first 16MB of address space.
309 Disable if no such devices will be used.
310
311 If unsure, say Y.
312
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313config SMP
314 bool "Symmetric multi-processing support"
315 ---help---
316 This enables support for systems with more than one CPU. If you have
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317 a system with only one CPU, say N. If you have a system with more
318 than one CPU, say Y.
506f1d07 319
4a474157 320 If you say N here, the kernel will run on uni- and multiprocessor
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SR
321 machines, but will use only one CPU of a multiprocessor machine. If
322 you say Y here, the kernel will run on many, but not all,
4a474157 323 uniprocessor machines. On a uniprocessor machine, the kernel
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SR
324 will run faster if you say N here.
325
326 Note that if you say Y here and choose architecture "586" or
327 "Pentium" under "Processor family", the kernel will not work on 486
328 architectures. Similarly, multiprocessor kernels for the "PPro"
329 architecture may not work on all Pentium based boards.
330
331 People using multiprocessor machines who say Y here should also say
332 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
333 Management" code will be disabled if you say Y here.
334
395cf969 335 See also <file:Documentation/x86/i386/IO-APIC.txt>,
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SR
336 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
337 <http://www.tldp.org/docs.html#howto>.
338
339 If you don't know what to do here, say N.
340
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JT
341config X86_FEATURE_NAMES
342 bool "Processor feature human-readable names" if EMBEDDED
343 default y
344 ---help---
345 This option compiles in a table of x86 feature bits and corresponding
346 names. This is required to support /proc/cpuinfo and a few kernel
347 messages. You can disable this to save space, at the expense of
348 making those few kernel messages show numeric feature bits instead.
349
350 If in doubt, say Y.
351
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BP
352config X86_FAST_FEATURE_TESTS
353 bool "Fast CPU feature tests" if EMBEDDED
354 default y
355 ---help---
356 Some fast-paths in the kernel depend on the capabilities of the CPU.
357 Say Y here for the kernel to patch in the appropriate code at runtime
358 based on the capabilities of the CPU. The infrastructure for patching
359 code at runtime takes up some additional space; space-constrained
360 embedded systems may wish to say N here to produce smaller, slightly
361 slower code.
362
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363config X86_X2APIC
364 bool "Support x2apic"
19e3d60d 365 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
06cd9a7d
YL
366 ---help---
367 This enables x2apic support on CPUs that have this feature.
368
369 This allows 32-bit apic IDs (so it can support very large systems),
370 and accesses the local apic via MSRs not via mmio.
371
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372 If you don't know what to do here, say N.
373
6695c85b 374config X86_MPPARSE
6e87f9b7 375 bool "Enable MPS table" if ACPI || SFI
7a527688 376 default y
5ab74722 377 depends on X86_LOCAL_APIC
8f9ca475 378 ---help---
6695c85b
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379 For old smp systems that do not have proper acpi support. Newer systems
380 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 381
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382config X86_BIGSMP
383 bool "Support for big SMP systems with more than 8 CPUs"
384 depends on X86_32 && SMP
8f9ca475 385 ---help---
26f7ef14 386 This option is needed for the systems that have more than 8 CPUs
506f1d07 387
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388config GOLDFISH
389 def_bool y
390 depends on X86_GOLDFISH
391
8425091f 392if X86_32
c5c606d9
RT
393config X86_EXTENDED_PLATFORM
394 bool "Support for extended (non-PC) x86 platforms"
395 default y
8f9ca475 396 ---help---
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IM
397 If you disable this option then the kernel will only support
398 standard PC platforms. (which covers the vast majority of
399 systems out there.)
400
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401 If you enable this option then you'll be able to select support
402 for the following (non-PC) 32 bit x86 platforms:
cb7b8023 403 Goldfish (Android emulator)
8425091f 404 AMD Elan
8425091f
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405 RDC R-321x SoC
406 SGI 320/540 (Visual Workstation)
83125a3a 407 STA2X11-based (e.g. Northville)
3f4110a4 408 Moorestown MID devices
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409
410 If you have one of these systems, or if you want to build a
411 generic distribution kernel, say Y here - otherwise say N.
8425091f 412endif
06ac8346 413
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RT
414if X86_64
415config X86_EXTENDED_PLATFORM
416 bool "Support for extended (non-PC) x86 platforms"
417 default y
418 ---help---
419 If you disable this option then the kernel will only support
420 standard PC platforms. (which covers the vast majority of
421 systems out there.)
422
423 If you enable this option then you'll be able to select support
424 for the following (non-PC) 64 bit x86 platforms:
44b111b5 425 Numascale NumaChip
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426 ScaleMP vSMP
427 SGI Ultraviolet
428
429 If you have one of these systems, or if you want to build a
430 generic distribution kernel, say Y here - otherwise say N.
431endif
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RT
432# This is an alphabetically sorted list of 64 bit extended platforms
433# Please maintain the alphabetic order if and when there are additions
44b111b5
SP
434config X86_NUMACHIP
435 bool "Numascale NumaChip"
436 depends on X86_64
437 depends on X86_EXTENDED_PLATFORM
438 depends on NUMA
439 depends on SMP
440 depends on X86_X2APIC
f9726bfd 441 depends on PCI_MMCONFIG
44b111b5
SP
442 ---help---
443 Adds support for Numascale NumaChip large-SMP systems. Needed to
444 enable more than ~168 cores.
445 If you don't have one of these, you should say N here.
506f1d07 446
c5c606d9
RT
447config X86_VSMP
448 bool "ScaleMP vSMP"
6276a074 449 select HYPERVISOR_GUEST
c5c606d9
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450 select PARAVIRT
451 depends on X86_64 && PCI
452 depends on X86_EXTENDED_PLATFORM
ead91d4b 453 depends on SMP
8f9ca475 454 ---help---
c5c606d9
RT
455 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
456 supposed to run on these EM64T-based machines. Only choose this option
457 if you have one of these machines.
5e3a77e9 458
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NP
459config X86_UV
460 bool "SGI Ultraviolet"
461 depends on X86_64
c5c606d9 462 depends on X86_EXTENDED_PLATFORM
54c28d29 463 depends on NUMA
9d6c26e7 464 depends on X86_X2APIC
1222e564 465 depends on PCI
8f9ca475 466 ---help---
03b48632
NP
467 This option is needed in order to support SGI Ultraviolet systems.
468 If you don't have one of these, you should say N here.
469
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470# Following is an alphabetically sorted list of 32 bit extended platforms
471# Please maintain the alphabetic order if and when there are additions
506f1d07 472
ddd70cf9
JN
473config X86_GOLDFISH
474 bool "Goldfish (Virtual Platform)"
cb7b8023 475 depends on X86_EXTENDED_PLATFORM
ddd70cf9
JN
476 ---help---
477 Enable support for the Goldfish virtual platform used primarily
478 for Android development. Unless you are building for the Android
479 Goldfish emulator say N here.
480
c751e17b
TG
481config X86_INTEL_CE
482 bool "CE4100 TV platform"
483 depends on PCI
484 depends on PCI_GODIRECT
6084a6e2 485 depends on X86_IO_APIC
c751e17b
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486 depends on X86_32
487 depends on X86_EXTENDED_PLATFORM
37bc9f50 488 select X86_REBOOTFIXUPS
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489 select OF
490 select OF_EARLY_FLATTREE
c751e17b
TG
491 ---help---
492 Select for the Intel CE media processor (CE4100) SOC.
493 This option compiles in support for the CE4100 SOC for settop
494 boxes and media devices.
495
4cb9b00f 496config X86_INTEL_MID
43605ef1
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497 bool "Intel MID platform support"
498 depends on X86_32
499 depends on X86_EXTENDED_PLATFORM
edc6bc78 500 depends on X86_PLATFORM_DEVICES
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501 depends on PCI
502 depends on PCI_GOANY
503 depends on X86_IO_APIC
7c9c3a1e 504 select SFI
4cb9b00f 505 select I2C
7c9c3a1e 506 select DW_APB_TIMER
1ea7c673 507 select APB_TIMER
1ea7c673 508 select INTEL_SCU_IPC
15a713df 509 select MFD_INTEL_MSIC
1ea7c673 510 ---help---
4cb9b00f
DC
511 Select to build a kernel capable of supporting Intel MID (Mobile
512 Internet Device) platform systems which do not have the PCI legacy
513 interfaces. If you are building for a PC class system say N here.
1ea7c673 514
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DC
515 Intel MID platforms are based on an Intel processor and chipset which
516 consume less power than most of the x86 derivatives.
43605ef1 517
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518config X86_INTEL_QUARK
519 bool "Intel Quark platform support"
520 depends on X86_32
521 depends on X86_EXTENDED_PLATFORM
522 depends on X86_PLATFORM_DEVICES
523 depends on X86_TSC
524 depends on PCI
525 depends on PCI_GOANY
526 depends on X86_IO_APIC
527 select IOSF_MBI
528 select INTEL_IMR
9ab6eb51 529 select COMMON_CLK
8bbc2a13
BD
530 ---help---
531 Select to include support for Quark X1000 SoC.
532 Say Y here if you have a Quark based system such as the Arduino
533 compatible Intel Galileo.
534
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MW
535config X86_INTEL_LPSS
536 bool "Intel Low Power Subsystem Support"
eebb3e8d 537 depends on X86 && ACPI
3d48aab1 538 select COMMON_CLK
0f531431 539 select PINCTRL
eebb3e8d 540 select IOSF_MBI
3d48aab1
MW
541 ---help---
542 Select to build support for Intel Low Power Subsystem such as
543 found on Intel Lynxpoint PCH. Selecting this option enables
0f531431
MN
544 things like clock tree (common clock framework) and pincontrol
545 which are needed by the LPSS peripheral drivers.
3d48aab1 546
92082a88
KX
547config X86_AMD_PLATFORM_DEVICE
548 bool "AMD ACPI2Platform devices support"
549 depends on ACPI
550 select COMMON_CLK
551 select PINCTRL
552 ---help---
553 Select to interpret AMD specific ACPI device to platform device
554 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
555 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
556 implemented under PINCTRL subsystem.
557
ced3ce76
DB
558config IOSF_MBI
559 tristate "Intel SoC IOSF Sideband support for SoC platforms"
560 depends on PCI
561 ---help---
562 This option enables sideband register access support for Intel SoC
563 platforms. On these platforms the IOSF sideband is used in lieu of
564 MSR's for some register accesses, mostly but not limited to thermal
565 and power. Drivers may query the availability of this device to
566 determine if they need the sideband in order to work on these
567 platforms. The sideband is available on the following SoC products.
568 This list is not meant to be exclusive.
569 - BayTrail
570 - Braswell
571 - Quark
572
573 You should say Y if you are running a kernel on one of these SoC's.
574
ed2226bd
DB
575config IOSF_MBI_DEBUG
576 bool "Enable IOSF sideband access through debugfs"
577 depends on IOSF_MBI && DEBUG_FS
578 ---help---
579 Select this option to expose the IOSF sideband access registers (MCR,
580 MDR, MCRX) through debugfs to write and read register information from
581 different units on the SoC. This is most useful for obtaining device
582 state information for debug and analysis. As this is a general access
583 mechanism, users of this option would have specific knowledge of the
584 device they want to access.
585
586 If you don't require the option or are in doubt, say N.
587
c5c606d9
RT
588config X86_RDC321X
589 bool "RDC R-321x SoC"
506f1d07 590 depends on X86_32
c5c606d9
RT
591 depends on X86_EXTENDED_PLATFORM
592 select M486
593 select X86_REBOOTFIXUPS
594 ---help---
595 This option is needed for RDC R-321x system-on-chip, also known
596 as R-8610-(G).
597 If you don't have one of these chips, you should say N here.
598
e0c7ae37 599config X86_32_NON_STANDARD
9c398017
IM
600 bool "Support non-standard 32-bit SMP architectures"
601 depends on X86_32 && SMP
c5c606d9 602 depends on X86_EXTENDED_PLATFORM
8f9ca475 603 ---help---
b5660ba7
PA
604 This option compiles in the bigsmp and STA2X11 default
605 subarchitectures. It is intended for a generic binary
606 kernel. If you select them all, kernel will probe it one by
607 one and will fallback to default.
d49c4288 608
c5c606d9 609# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 610
d949f36f 611config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 612 def_bool y
d949f36f
LT
613 # MCE code calls memory_failure():
614 depends on X86_MCE
615 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
d949f36f
LT
616 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
617 depends on X86_64 || !SPARSEMEM
618 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 619
83125a3a
AR
620config STA2X11
621 bool "STA2X11 Companion Chip Support"
622 depends on X86_32_NON_STANDARD && PCI
623 select X86_DEV_DMA_OPS
624 select X86_DMA_REMAP
625 select SWIOTLB
626 select MFD_STA2X11
627 select ARCH_REQUIRE_GPIOLIB
628 default n
629 ---help---
630 This adds support for boards based on the STA2X11 IO-Hub,
631 a.k.a. "ConneXt". The chip is used in place of the standard
632 PC chipset, so all "standard" peripherals are missing. If this
633 option is selected the kernel will still be able to boot on
634 standard PC machines.
635
82148d1d
S
636config X86_32_IRIS
637 tristate "Eurobraille/Iris poweroff module"
638 depends on X86_32
639 ---help---
640 The Iris machines from EuroBraille do not have APM or ACPI support
641 to shut themselves down properly. A special I/O sequence is
642 needed to do so, which is what this module does at
643 kernel shutdown.
644
645 This is only for Iris machines from EuroBraille.
646
647 If unused, say N.
648
ae1e9130 649config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
650 def_bool y
651 prompt "Single-depth WCHAN output"
a87d0914 652 depends on X86
8f9ca475 653 ---help---
506f1d07
SR
654 Calculate simpler /proc/<PID>/wchan values. If this option
655 is disabled then wchan values will recurse back to the
656 caller function. This provides more accurate wchan values,
657 at the expense of slightly more scheduling overhead.
658
659 If in doubt, say "Y".
660
6276a074
BP
661menuconfig HYPERVISOR_GUEST
662 bool "Linux guest support"
8f9ca475 663 ---help---
6276a074
BP
664 Say Y here to enable options for running Linux under various hyper-
665 visors. This option enables basic hypervisor detection and platform
666 setup.
506f1d07 667
6276a074
BP
668 If you say N, all options in this submenu will be skipped and
669 disabled, and Linux guest support won't be built in.
506f1d07 670
6276a074 671if HYPERVISOR_GUEST
506f1d07 672
e61bd94a
EPH
673config PARAVIRT
674 bool "Enable paravirtualization code"
8f9ca475 675 ---help---
e61bd94a
EPH
676 This changes the kernel so it can modify itself when it is run
677 under a hypervisor, potentially improving performance significantly
678 over full virtualization. However, when run without a hypervisor
679 the kernel is theoretically slower and slightly larger.
680
6276a074
BP
681config PARAVIRT_DEBUG
682 bool "paravirt-ops debugging"
683 depends on PARAVIRT && DEBUG_KERNEL
684 ---help---
685 Enable to debug paravirt_ops internals. Specifically, BUG if
686 a paravirt_op is missing when it is called.
687
b4ecc126
JF
688config PARAVIRT_SPINLOCKS
689 bool "Paravirtualization layer for spinlocks"
6ea30386 690 depends on PARAVIRT && SMP
62c7a1e9 691 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
b4ecc126
JF
692 ---help---
693 Paravirtualized spinlocks allow a pvops backend to replace the
694 spinlock implementation with something virtualization-friendly
695 (for example, block the virtual CPU rather than spinning).
696
4c4e4f61
R
697 It has a minimal impact on native kernels and gives a nice performance
698 benefit on paravirtualized KVM / Xen kernels.
b4ecc126 699
4c4e4f61 700 If you are unsure how to answer this question, answer Y.
b4ecc126 701
45e898b7
WL
702config QUEUED_LOCK_STAT
703 bool "Paravirt queued spinlock statistics"
704 depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS
705 ---help---
706 Enable the collection of statistical data on the slowpath
707 behavior of paravirtualized queued spinlocks and report
708 them on debugfs.
709
6276a074 710source "arch/x86/xen/Kconfig"
7af192c9 711
6276a074
BP
712config KVM_GUEST
713 bool "KVM Guest support (including kvmclock)"
714 depends on PARAVIRT
715 select PARAVIRT_CLOCK
716 default y
8f9ca475 717 ---help---
6276a074
BP
718 This option enables various optimizations for running under the KVM
719 hypervisor. It includes a paravirtualized clock, so that instead
720 of relying on a PIT (or probably other) emulation by the
721 underlying device model, the host provides the guest with
722 timing infrastructure such as time of day, and system time
506f1d07 723
1e20eb85
SV
724config KVM_DEBUG_FS
725 bool "Enable debug information for KVM Guests in debugfs"
726 depends on KVM_GUEST && DEBUG_FS
727 default n
728 ---help---
729 This option enables collection of various statistics for KVM guest.
730 Statistics are displayed in debugfs filesystem. Enabling this option
731 may incur significant overhead.
732
6276a074
BP
733source "arch/x86/lguest/Kconfig"
734
735config PARAVIRT_TIME_ACCOUNTING
736 bool "Paravirtual steal time accounting"
737 depends on PARAVIRT
738 default n
8f9ca475 739 ---help---
6276a074
BP
740 Select this option to enable fine granularity task steal time
741 accounting. Time spent executing other tasks in parallel with
742 the current vCPU is discounted from the vCPU power. To account for
743 that, there can be a small performance impact.
744
745 If in doubt, say N here.
746
747config PARAVIRT_CLOCK
748 bool
97349135 749
6276a074 750endif #HYPERVISOR_GUEST
97349135 751
08677214 752config NO_BOOTMEM
774ea0bc 753 def_bool y
08677214 754
506f1d07
SR
755source "arch/x86/Kconfig.cpu"
756
757config HPET_TIMER
3c2362e6 758 def_bool X86_64
506f1d07 759 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
760 ---help---
761 Use the IA-PC HPET (High Precision Event Timer) to manage
762 time in preference to the PIT and RTC, if a HPET is
763 present.
764 HPET is the next generation timer replacing legacy 8254s.
765 The HPET provides a stable time base on SMP
766 systems, unlike the TSC, but it is more expensive to access,
767 as it is off-chip. You can find the HPET spec at
768 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
506f1d07 769
8f9ca475
IM
770 You can safely choose Y here. However, HPET will only be
771 activated if the platform and the BIOS support this feature.
772 Otherwise the 8254 will be used for timing services.
506f1d07 773
8f9ca475 774 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
775
776config HPET_EMULATE_RTC
3c2362e6 777 def_bool y
9d8af78b 778 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 779
bb24c471 780config APB_TIMER
933b9463
AC
781 def_bool y if X86_INTEL_MID
782 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
06c3df49 783 select DW_APB_TIMER
a0c3832a 784 depends on X86_INTEL_MID && SFI
bb24c471
JP
785 help
786 APB timer is the replacement for 8254, HPET on X86 MID platforms.
787 The APBT provides a stable time base on SMP
788 systems, unlike the TSC, but it is more expensive to access,
789 as it is off-chip. APB timers are always running regardless of CPU
790 C states, they are used as per CPU clockevent device when possible.
791
6a108a14 792# Mark as expert because too many people got it wrong.
506f1d07 793# The code disables itself when not needed.
7ae9392c
TP
794config DMI
795 default y
cf074402 796 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
6a108a14 797 bool "Enable DMI scanning" if EXPERT
8f9ca475 798 ---help---
7ae9392c
TP
799 Enabled scanning of DMI to identify machine quirks. Say Y
800 here unless you have verified that your setup is not
801 affected by entries in the DMI blacklist. Required by PNP
802 BIOS code.
803
506f1d07 804config GART_IOMMU
38901f1c 805 bool "Old AMD GART IOMMU support"
506f1d07 806 select SWIOTLB
23ac4ae8 807 depends on X86_64 && PCI && AMD_NB
8f9ca475 808 ---help---
ced3c42c
IM
809 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
810 GART based hardware IOMMUs.
811
812 The GART supports full DMA access for devices with 32-bit access
813 limitations, on systems with more than 3 GB. This is usually needed
814 for USB, sound, many IDE/SATA chipsets and some other devices.
815
816 Newer systems typically have a modern AMD IOMMU, supported via
817 the CONFIG_AMD_IOMMU=y config option.
818
819 In normal configurations this driver is only active when needed:
820 there's more than 3 GB of memory and the system contains a
821 32-bit limited device.
822
823 If unsure, say Y.
506f1d07
SR
824
825config CALGARY_IOMMU
826 bool "IBM Calgary IOMMU support"
827 select SWIOTLB
6ea30386 828 depends on X86_64 && PCI
8f9ca475 829 ---help---
506f1d07
SR
830 Support for hardware IOMMUs in IBM's xSeries x366 and x460
831 systems. Needed to run systems with more than 3GB of memory
832 properly with 32-bit PCI devices that do not support DAC
833 (Double Address Cycle). Calgary also supports bus level
834 isolation, where all DMAs pass through the IOMMU. This
835 prevents them from going anywhere except their intended
836 destination. This catches hard-to-find kernel bugs and
837 mis-behaving drivers and devices that do not use the DMA-API
838 properly to set up their DMA buffers. The IOMMU can be
839 turned off at boot time with the iommu=off parameter.
840 Normally the kernel will make the right choice by itself.
841 If unsure, say Y.
842
843config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
844 def_bool y
845 prompt "Should Calgary be enabled by default?"
506f1d07 846 depends on CALGARY_IOMMU
8f9ca475 847 ---help---
506f1d07
SR
848 Should Calgary be enabled by default? if you choose 'y', Calgary
849 will be used (if it exists). If you choose 'n', Calgary will not be
850 used even if it exists. If you choose 'n' and would like to use
851 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
852 If unsure, say Y.
853
854# need this always selected by IOMMU for the VIA workaround
855config SWIOTLB
a1afd01c 856 def_bool y if X86_64
8f9ca475 857 ---help---
506f1d07 858 Support for software bounce buffers used on x86-64 systems
4454d327
JM
859 which don't have a hardware IOMMU. Using this PCI devices
860 which can only access 32-bits of memory can be used on systems
861 with more than 3 GB of memory.
862 If unsure, say Y.
506f1d07 863
a8522509 864config IOMMU_HELPER
3120e25e
JB
865 def_bool y
866 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
d25e26b6 867
1184dc2f 868config MAXSMP
ddb0c5a6 869 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
6ea30386 870 depends on X86_64 && SMP && DEBUG_KERNEL
36f5101a 871 select CPUMASK_OFFSTACK
8f9ca475 872 ---help---
ddb0c5a6 873 Enable maximum number of CPUS and NUMA Nodes for this architecture.
1184dc2f 874 If unsure, say N.
506f1d07
SR
875
876config NR_CPUS
36f5101a 877 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 878 range 2 8 if SMP && X86_32 && !X86_BIGSMP
bb61ccc7 879 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
b53b5eda 880 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
78637a97 881 default "1" if !SMP
b53b5eda 882 default "8192" if MAXSMP
b5660ba7 883 default "32" if SMP && X86_BIGSMP
c5c19941
KS
884 default "8" if SMP && X86_32
885 default "64" if SMP
8f9ca475 886 ---help---
506f1d07 887 This allows you to specify the maximum number of CPUs which this
bb61ccc7 888 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
cad14bb9 889 supported value is 8192, otherwise the maximum value is 512. The
506f1d07
SR
890 minimum value which makes sense is 2.
891
892 This is purely to save memory - each supported CPU adds
893 approximately eight kilobytes to the kernel image.
894
895config SCHED_SMT
896 bool "SMT (Hyperthreading) scheduler support"
c8e56d20 897 depends on SMP
8f9ca475 898 ---help---
506f1d07
SR
899 SMT scheduler support improves the CPU scheduler's decision making
900 when dealing with Intel Pentium 4 chips with HyperThreading at a
901 cost of slightly increased overhead in some places. If unsure say
902 N here.
903
904config SCHED_MC
3c2362e6
HH
905 def_bool y
906 prompt "Multi-core scheduler support"
c8e56d20 907 depends on SMP
8f9ca475 908 ---help---
506f1d07
SR
909 Multi-core scheduler support improves the CPU scheduler's decision
910 making when dealing with multi-core CPU chips at a cost of slightly
911 increased overhead in some places. If unsure say N here.
912
913source "kernel/Kconfig.preempt"
914
30b8b006
TG
915config UP_LATE_INIT
916 def_bool y
ba360f88 917 depends on !SMP && X86_LOCAL_APIC
30b8b006 918
506f1d07 919config X86_UP_APIC
50849eef
JB
920 bool "Local APIC support on uniprocessors" if !PCI_MSI
921 default PCI_MSI
38a1dfda 922 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 923 ---help---
506f1d07
SR
924 A local APIC (Advanced Programmable Interrupt Controller) is an
925 integrated interrupt controller in the CPU. If you have a single-CPU
926 system which has a processor with a local APIC, you can say Y here to
927 enable and use it. If you say Y here even though your machine doesn't
928 have a local APIC, then the kernel will still run with no slowdown at
929 all. The local APIC supports CPU-generated self-interrupts (timer,
930 performance counters), and the NMI watchdog which detects hard
931 lockups.
932
933config X86_UP_IOAPIC
934 bool "IO-APIC support on uniprocessors"
935 depends on X86_UP_APIC
8f9ca475 936 ---help---
506f1d07
SR
937 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
938 SMP-capable replacement for PC-style interrupt controllers. Most
939 SMP systems and many recent uniprocessor systems have one.
940
941 If you have a single-CPU system with an IO-APIC, you can say Y here
942 to use it. If you say Y here even though your machine doesn't have
943 an IO-APIC, then the kernel will still run with no slowdown at all.
944
945config X86_LOCAL_APIC
3c2362e6 946 def_bool y
0dbc6078 947 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
b5dc8e6c 948 select IRQ_DOMAIN_HIERARCHY
52f518a3 949 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
506f1d07
SR
950
951config X86_IO_APIC
b1da1e71
JB
952 def_bool y
953 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
506f1d07 954
41b9eb26
SA
955config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
956 bool "Reroute for broken boot IRQs"
41b9eb26 957 depends on X86_IO_APIC
8f9ca475 958 ---help---
41b9eb26
SA
959 This option enables a workaround that fixes a source of
960 spurious interrupts. This is recommended when threaded
961 interrupt handling is used on systems where the generation of
962 superfluous "boot interrupts" cannot be disabled.
963
964 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
965 entry in the chipset's IO-APIC is masked (as, e.g. the RT
966 kernel does during interrupt handling). On chipsets where this
967 boot IRQ generation cannot be disabled, this workaround keeps
968 the original IRQ line masked so that only the equivalent "boot
969 IRQ" is delivered to the CPUs. The workaround also tells the
970 kernel to set up the IRQ handler on the boot IRQ line. In this
971 way only one interrupt is delivered to the kernel. Otherwise
972 the spurious second interrupt may cause the kernel to bring
973 down (vital) interrupt lines.
974
975 Only affects "broken" chipsets. Interrupt sharing may be
976 increased on these systems.
977
506f1d07 978config X86_MCE
bab9bc65 979 bool "Machine Check / overheating reporting"
648ed940 980 select GENERIC_ALLOCATOR
e57dbaf7 981 default y
506f1d07 982 ---help---
bab9bc65
AK
983 Machine Check support allows the processor to notify the
984 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 985 The action the kernel takes depends on the severity of the problem,
bab9bc65 986 ranging from warning messages to halting the machine.
4efc0670 987
506f1d07 988config X86_MCE_INTEL
3c2362e6
HH
989 def_bool y
990 prompt "Intel MCE features"
c1ebf835 991 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 992 ---help---
506f1d07
SR
993 Additional support for intel specific MCE features such as
994 the thermal monitor.
995
996config X86_MCE_AMD
3c2362e6
HH
997 def_bool y
998 prompt "AMD MCE features"
c1ebf835 999 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 1000 ---help---
506f1d07
SR
1001 Additional support for AMD specific MCE features such as
1002 the DRAM Error Threshold.
1003
4efc0670 1004config X86_ANCIENT_MCE
6fc108a0 1005 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 1006 depends on X86_32 && X86_MCE
cd13adcc
HS
1007 ---help---
1008 Include support for machine check handling on old Pentium 5 or WinChip
5065a706 1009 systems. These typically need to be enabled explicitly on the command
cd13adcc 1010 line.
4efc0670 1011
b2762686
AK
1012config X86_MCE_THRESHOLD
1013 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 1014 def_bool y
b2762686 1015
ea149b36 1016config X86_MCE_INJECT
c1ebf835 1017 depends on X86_MCE
ea149b36
AK
1018 tristate "Machine check injector support"
1019 ---help---
1020 Provide support for injecting machine checks for testing purposes.
1021 If you don't know what a machine check is and you don't do kernel
1022 QA it is safe to say n.
1023
4efc0670
AK
1024config X86_THERMAL_VECTOR
1025 def_bool y
5bb38adc 1026 depends on X86_MCE_INTEL
4efc0670 1027
5aef51c3 1028config X86_LEGACY_VM86
1e642812 1029 bool "Legacy VM86 support"
5aef51c3 1030 default n
506f1d07 1031 depends on X86_32
8f9ca475 1032 ---help---
5aef51c3
AL
1033 This option allows user programs to put the CPU into V8086
1034 mode, which is an 80286-era approximation of 16-bit real mode.
1035
1036 Some very old versions of X and/or vbetool require this option
1037 for user mode setting. Similarly, DOSEMU will use it if
1038 available to accelerate real mode DOS programs. However, any
1039 recent version of DOSEMU, X, or vbetool should be fully
1040 functional even without kernel VM86 support, as they will all
1e642812
IM
1041 fall back to software emulation. Nevertheless, if you are using
1042 a 16-bit DOS program where 16-bit performance matters, vm86
1043 mode might be faster than emulation and you might want to
1044 enable this option.
5aef51c3 1045
1e642812
IM
1046 Note that any app that works on a 64-bit kernel is unlikely to
1047 need this option, as 64-bit kernels don't, and can't, support
1048 V8086 mode. This option is also unrelated to 16-bit protected
1049 mode and is not needed to run most 16-bit programs under Wine.
5aef51c3 1050
1e642812
IM
1051 Enabling this option increases the complexity of the kernel
1052 and slows down exception handling a tiny bit.
5aef51c3 1053
1e642812 1054 If unsure, say N here.
5aef51c3
AL
1055
1056config VM86
1057 bool
1058 default X86_LEGACY_VM86
34273f41
PA
1059
1060config X86_16BIT
1061 bool "Enable support for 16-bit segments" if EXPERT
1062 default y
a5b9e5a2 1063 depends on MODIFY_LDT_SYSCALL
34273f41
PA
1064 ---help---
1065 This option is required by programs like Wine to run 16-bit
1066 protected mode legacy code on x86 processors. Disabling
1067 this option saves about 300 bytes on i386, or around 6K text
1068 plus 16K runtime memory on x86-64,
1069
1070config X86_ESPFIX32
1071 def_bool y
1072 depends on X86_16BIT && X86_32
506f1d07 1073
197725de
PA
1074config X86_ESPFIX64
1075 def_bool y
34273f41 1076 depends on X86_16BIT && X86_64
506f1d07 1077
1ad83c85
AL
1078config X86_VSYSCALL_EMULATION
1079 bool "Enable vsyscall emulation" if EXPERT
1080 default y
1081 depends on X86_64
1082 ---help---
1083 This enables emulation of the legacy vsyscall page. Disabling
1084 it is roughly equivalent to booting with vsyscall=none, except
1085 that it will also disable the helpful warning if a program
1086 tries to use a vsyscall. With this option set to N, offending
1087 programs will just segfault, citing addresses of the form
1088 0xffffffffff600?00.
1089
1090 This option is required by many programs built before 2013, and
1091 care should be used even with newer programs if set to N.
1092
1093 Disabling this option saves about 7K of kernel size and
1094 possibly 4K of additional runtime pagetable memory.
1095
506f1d07
SR
1096config TOSHIBA
1097 tristate "Toshiba Laptop support"
1098 depends on X86_32
1099 ---help---
1100 This adds a driver to safely access the System Management Mode of
1101 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1102 not work on models with a Phoenix BIOS. The System Management Mode
1103 is used to set the BIOS and power saving options on Toshiba portables.
1104
1105 For information on utilities to make use of this driver see the
1106 Toshiba Linux utilities web site at:
1107 <http://www.buzzard.org.uk/toshiba/>.
1108
1109 Say Y if you intend to run this kernel on a Toshiba portable.
1110 Say N otherwise.
1111
1112config I8K
039ae585 1113 tristate "Dell i8k legacy laptop support"
949a9d70 1114 select HWMON
039ae585 1115 select SENSORS_DELL_SMM
506f1d07 1116 ---help---
039ae585
PR
1117 This option enables legacy /proc/i8k userspace interface in hwmon
1118 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1119 temperature and allows controlling fan speeds of Dell laptops via
1120 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1121 it reports also power and hotkey status. For fan speed control is
1122 needed userspace package i8kutils.
1123
1124 Say Y if you intend to run this kernel on old Dell laptops or want to
1125 use userspace package i8kutils.
506f1d07
SR
1126 Say N otherwise.
1127
1128config X86_REBOOTFIXUPS
9ba16087
JB
1129 bool "Enable X86 board specific fixups for reboot"
1130 depends on X86_32
506f1d07
SR
1131 ---help---
1132 This enables chipset and/or board specific fixups to be done
1133 in order to get reboot to work correctly. This is only needed on
1134 some combinations of hardware and BIOS. The symptom, for which
1135 this config is intended, is when reboot ends with a stalled/hung
1136 system.
1137
1138 Currently, the only fixup is for the Geode machines using
5e3a77e9 1139 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
1140
1141 Say Y if you want to enable the fixup. Currently, it's safe to
1142 enable this option even if you don't need it.
1143 Say N otherwise.
1144
1145config MICROCODE
9a2bc335
BP
1146 bool "CPU microcode loading support"
1147 default y
80030e3d 1148 depends on CPU_SUP_AMD || CPU_SUP_INTEL
fe055896 1149 depends on BLK_DEV_INITRD
506f1d07
SR
1150 select FW_LOADER
1151 ---help---
e43f6e67 1152
506f1d07 1153 If you say Y here, you will be able to update the microcode on
80cc9f10 1154 certain Intel and AMD processors. The Intel support is for the
e43f6e67
BP
1155 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1156 Xeon etc. The AMD support is for families 0x10 and later. You will
1157 obviously need the actual microcode binary data itself which is not
1158 shipped with the Linux kernel.
506f1d07 1159
8d86f390
PO
1160 This option selects the general module only, you need to select
1161 at least one vendor specific module as well.
506f1d07 1162
e43f6e67
BP
1163 To compile this driver as a module, choose M here: the module
1164 will be called microcode.
506f1d07 1165
8d86f390 1166config MICROCODE_INTEL
e43f6e67 1167 bool "Intel microcode loading support"
8f9ca475
IM
1168 depends on MICROCODE
1169 default MICROCODE
1170 select FW_LOADER
1171 ---help---
1172 This options enables microcode patch loading support for Intel
1173 processors.
1174
b8989db9
A
1175 For the current Intel microcode data package go to
1176 <https://downloadcenter.intel.com> and search for
1177 'Linux Processor Microcode Data File'.
8d86f390 1178
80cc9f10 1179config MICROCODE_AMD
e43f6e67 1180 bool "AMD microcode loading support"
8f9ca475
IM
1181 depends on MICROCODE
1182 select FW_LOADER
1183 ---help---
1184 If you select this option, microcode patch loading support for AMD
1185 processors will be enabled.
80cc9f10 1186
8f9ca475 1187config MICROCODE_OLD_INTERFACE
3c2362e6 1188 def_bool y
506f1d07 1189 depends on MICROCODE
506f1d07
SR
1190
1191config X86_MSR
1192 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1193 ---help---
506f1d07
SR
1194 This device gives privileged processes access to the x86
1195 Model-Specific Registers (MSRs). It is a character device with
1196 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1197 MSR accesses are directed to a specific CPU on multi-processor
1198 systems.
1199
1200config X86_CPUID
1201 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1202 ---help---
506f1d07
SR
1203 This device gives processes access to the x86 CPUID instruction to
1204 be executed on a specific processor. It is a character device
1205 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1206 /dev/cpu/31/cpuid.
1207
1208choice
1209 prompt "High Memory Support"
6fc108a0 1210 default HIGHMEM4G
506f1d07
SR
1211 depends on X86_32
1212
1213config NOHIGHMEM
1214 bool "off"
506f1d07
SR
1215 ---help---
1216 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1217 However, the address space of 32-bit x86 processors is only 4
1218 Gigabytes large. That means that, if you have a large amount of
1219 physical memory, not all of it can be "permanently mapped" by the
1220 kernel. The physical memory that's not permanently mapped is called
1221 "high memory".
1222
1223 If you are compiling a kernel which will never run on a machine with
1224 more than 1 Gigabyte total physical RAM, answer "off" here (default
1225 choice and suitable for most users). This will result in a "3GB/1GB"
1226 split: 3GB are mapped so that each process sees a 3GB virtual memory
1227 space and the remaining part of the 4GB virtual memory space is used
1228 by the kernel to permanently map as much physical memory as
1229 possible.
1230
1231 If the machine has between 1 and 4 Gigabytes physical RAM, then
1232 answer "4GB" here.
1233
1234 If more than 4 Gigabytes is used then answer "64GB" here. This
1235 selection turns Intel PAE (Physical Address Extension) mode on.
1236 PAE implements 3-level paging on IA32 processors. PAE is fully
1237 supported by Linux, PAE mode is implemented on all recent Intel
1238 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1239 then the kernel will not boot on CPUs that don't support PAE!
1240
1241 The actual amount of total physical memory will either be
1242 auto detected or can be forced by using a kernel command line option
1243 such as "mem=256M". (Try "man bootparam" or see the documentation of
1244 your boot loader (lilo or loadlin) about how to pass options to the
1245 kernel at boot time.)
1246
1247 If unsure, say "off".
1248
1249config HIGHMEM4G
1250 bool "4GB"
8f9ca475 1251 ---help---
506f1d07
SR
1252 Select this if you have a 32-bit processor and between 1 and 4
1253 gigabytes of physical RAM.
1254
1255config HIGHMEM64G
1256 bool "64GB"
eb068e78 1257 depends on !M486
506f1d07 1258 select X86_PAE
8f9ca475 1259 ---help---
506f1d07
SR
1260 Select this if you have a 32-bit processor and more than 4
1261 gigabytes of physical RAM.
1262
1263endchoice
1264
1265choice
6a108a14 1266 prompt "Memory split" if EXPERT
506f1d07
SR
1267 default VMSPLIT_3G
1268 depends on X86_32
8f9ca475 1269 ---help---
506f1d07
SR
1270 Select the desired split between kernel and user memory.
1271
1272 If the address range available to the kernel is less than the
1273 physical memory installed, the remaining memory will be available
1274 as "high memory". Accessing high memory is a little more costly
1275 than low memory, as it needs to be mapped into the kernel first.
1276 Note that increasing the kernel address space limits the range
1277 available to user programs, making the address space there
1278 tighter. Selecting anything other than the default 3G/1G split
1279 will also likely make your kernel incompatible with binary-only
1280 kernel modules.
1281
1282 If you are not absolutely sure what you are doing, leave this
1283 option alone!
1284
1285 config VMSPLIT_3G
1286 bool "3G/1G user/kernel split"
1287 config VMSPLIT_3G_OPT
1288 depends on !X86_PAE
1289 bool "3G/1G user/kernel split (for full 1G low memory)"
1290 config VMSPLIT_2G
1291 bool "2G/2G user/kernel split"
1292 config VMSPLIT_2G_OPT
1293 depends on !X86_PAE
1294 bool "2G/2G user/kernel split (for full 2G low memory)"
1295 config VMSPLIT_1G
1296 bool "1G/3G user/kernel split"
1297endchoice
1298
1299config PAGE_OFFSET
1300 hex
1301 default 0xB0000000 if VMSPLIT_3G_OPT
1302 default 0x80000000 if VMSPLIT_2G
1303 default 0x78000000 if VMSPLIT_2G_OPT
1304 default 0x40000000 if VMSPLIT_1G
1305 default 0xC0000000
1306 depends on X86_32
1307
1308config HIGHMEM
3c2362e6 1309 def_bool y
506f1d07 1310 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1311
1312config X86_PAE
9ba16087 1313 bool "PAE (Physical Address Extension) Support"
506f1d07 1314 depends on X86_32 && !HIGHMEM4G
9d99c712 1315 select SWIOTLB
8f9ca475 1316 ---help---
506f1d07
SR
1317 PAE is required for NX support, and furthermore enables
1318 larger swapspace support for non-overcommit purposes. It
1319 has the cost of more pagetable lookup overhead, and also
1320 consumes more pagetable space per process.
1321
600715dc 1322config ARCH_PHYS_ADDR_T_64BIT
3120e25e
JB
1323 def_bool y
1324 depends on X86_64 || X86_PAE
600715dc 1325
66f2b061 1326config ARCH_DMA_ADDR_T_64BIT
3120e25e
JB
1327 def_bool y
1328 depends on X86_64 || HIGHMEM64G
66f2b061 1329
10971ab2 1330config X86_DIRECT_GBPAGES
e5008abe
LR
1331 def_bool y
1332 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
8f9ca475 1333 ---help---
10971ab2
IM
1334 Certain kernel features effectively disable kernel
1335 linear 1 GB mappings (even if the CPU otherwise
1336 supports them), so don't confuse the user by printing
1337 that we have them enabled.
9e899816 1338
506f1d07
SR
1339# Common NUMA Features
1340config NUMA
fd51b2d7 1341 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1342 depends on SMP
b5660ba7
PA
1343 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1344 default y if X86_BIGSMP
8f9ca475 1345 ---help---
506f1d07 1346 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1347
506f1d07
SR
1348 The kernel will try to allocate memory used by a CPU on the
1349 local memory controller of the CPU and add some more
1350 NUMA awareness to the kernel.
1351
c280ea5e 1352 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1353 (or later), AMD Opteron, or EM64T NUMA.
1354
b5660ba7 1355 For 32-bit this is only needed if you boot a 32-bit
7cf6c945 1356 kernel on a 64-bit NUMA platform.
fd51b2d7
KM
1357
1358 Otherwise, you should say N.
506f1d07 1359
eec1d4fa 1360config AMD_NUMA
3c2362e6
HH
1361 def_bool y
1362 prompt "Old style AMD Opteron NUMA detection"
5da0ef9a 1363 depends on X86_64 && NUMA && PCI
8f9ca475 1364 ---help---
eec1d4fa
HR
1365 Enable AMD NUMA node topology detection. You should say Y here if
1366 you have a multi processor AMD system. This uses an old method to
1367 read the NUMA configuration directly from the builtin Northbridge
1368 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1369 which also takes priority if both are compiled in.
506f1d07
SR
1370
1371config X86_64_ACPI_NUMA
3c2362e6
HH
1372 def_bool y
1373 prompt "ACPI NUMA detection"
506f1d07
SR
1374 depends on X86_64 && NUMA && ACPI && PCI
1375 select ACPI_NUMA
8f9ca475 1376 ---help---
506f1d07
SR
1377 Enable ACPI SRAT based node topology detection.
1378
6ec6e0d9
SS
1379# Some NUMA nodes have memory ranges that span
1380# other nodes. Even though a pfn is valid and
1381# between a node's start and end pfns, it may not
1382# reside on that node. See memmap_init_zone()
1383# for details.
1384config NODES_SPAN_OTHER_NODES
1385 def_bool y
1386 depends on X86_64_ACPI_NUMA
1387
506f1d07
SR
1388config NUMA_EMU
1389 bool "NUMA emulation"
1b7e03ef 1390 depends on NUMA
8f9ca475 1391 ---help---
506f1d07
SR
1392 Enable NUMA emulation. A flat machine will be split
1393 into virtual nodes when booted with "numa=fake=N", where N is the
1394 number of nodes. This is only useful for debugging.
1395
1396config NODES_SHIFT
d25e26b6 1397 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1398 range 1 10
1399 default "10" if MAXSMP
506f1d07 1400 default "6" if X86_64
506f1d07
SR
1401 default "3"
1402 depends on NEED_MULTIPLE_NODES
8f9ca475 1403 ---help---
1184dc2f 1404 Specify the maximum number of NUMA Nodes available on the target
692105b8 1405 system. Increases memory reserved to accommodate various tables.
506f1d07 1406
506f1d07 1407config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1408 def_bool y
506f1d07 1409 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1410
1411config NEED_NODE_MEMMAP_SIZE
3c2362e6 1412 def_bool y
506f1d07 1413 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07 1414
506f1d07
SR
1415config ARCH_FLATMEM_ENABLE
1416 def_bool y
3b16651f 1417 depends on X86_32 && !NUMA
506f1d07
SR
1418
1419config ARCH_DISCONTIGMEM_ENABLE
1420 def_bool y
b263295d 1421 depends on NUMA && X86_32
506f1d07
SR
1422
1423config ARCH_DISCONTIGMEM_DEFAULT
1424 def_bool y
b263295d
CL
1425 depends on NUMA && X86_32
1426
506f1d07
SR
1427config ARCH_SPARSEMEM_ENABLE
1428 def_bool y
6ea30386 1429 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
506f1d07
SR
1430 select SPARSEMEM_STATIC if X86_32
1431 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1432
3b16651f
TH
1433config ARCH_SPARSEMEM_DEFAULT
1434 def_bool y
1435 depends on X86_64
1436
506f1d07
SR
1437config ARCH_SELECT_MEMORY_MODEL
1438 def_bool y
b263295d 1439 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1440
1441config ARCH_MEMORY_PROBE
a0842b70 1442 bool "Enable sysfs memory/probe interface"
3120e25e 1443 depends on X86_64 && MEMORY_HOTPLUG
a0842b70
TK
1444 help
1445 This option enables a sysfs memory/probe interface for testing.
1446 See Documentation/memory-hotplug.txt for more information.
1447 If you are unsure how to answer this question, answer N.
506f1d07 1448
3b16651f
TH
1449config ARCH_PROC_KCORE_TEXT
1450 def_bool y
1451 depends on X86_64 && PROC_KCORE
1452
a29815a3
AK
1453config ILLEGAL_POINTER_VALUE
1454 hex
1455 default 0 if X86_32
1456 default 0xdead000000000000 if X86_64
1457
506f1d07
SR
1458source "mm/Kconfig"
1459
7a67832c
DW
1460config X86_PMEM_LEGACY_DEVICE
1461 bool
1462
ec776ef6 1463config X86_PMEM_LEGACY
7a67832c 1464 tristate "Support non-standard NVDIMMs and ADR protected memory"
9f53f9fa
DW
1465 depends on PHYS_ADDR_T_64BIT
1466 depends on BLK_DEV
7a67832c 1467 select X86_PMEM_LEGACY_DEVICE
9f53f9fa 1468 select LIBNVDIMM
ec776ef6
CH
1469 help
1470 Treat memory marked using the non-standard e820 type of 12 as used
1471 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1472 The kernel will offer these regions to the 'pmem' driver so
1473 they can be used for persistent storage.
1474
1475 Say Y if unsure.
1476
506f1d07
SR
1477config HIGHPTE
1478 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1479 depends on HIGHMEM
8f9ca475 1480 ---help---
506f1d07
SR
1481 The VM uses one page table entry for each page of physical memory.
1482 For systems with a lot of RAM, this can be wasteful of precious
1483 low memory. Setting this option will put user-space page table
1484 entries in high memory.
1485
9f077871 1486config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1487 bool "Check for low memory corruption"
1488 ---help---
1489 Periodically check for memory corruption in low memory, which
1490 is suspected to be caused by BIOS. Even when enabled in the
1491 configuration, it is disabled at runtime. Enable it by
1492 setting "memory_corruption_check=1" on the kernel command
1493 line. By default it scans the low 64k of memory every 60
1494 seconds; see the memory_corruption_check_size and
1495 memory_corruption_check_period parameters in
1496 Documentation/kernel-parameters.txt to adjust this.
1497
1498 When enabled with the default parameters, this option has
1499 almost no overhead, as it reserves a relatively small amount
1500 of memory and scans it infrequently. It both detects corruption
1501 and prevents it from affecting the running system.
1502
1503 It is, however, intended as a diagnostic tool; if repeatable
1504 BIOS-originated corruption always affects the same memory,
1505 you can use memmap= to prevent the kernel from using that
1506 memory.
9f077871 1507
c885df50 1508config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1509 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1510 depends on X86_CHECK_BIOS_CORRUPTION
1511 default y
8f9ca475
IM
1512 ---help---
1513 Set whether the default state of memory_corruption_check is
1514 on or off.
c885df50 1515
9ea77bdb 1516config X86_RESERVE_LOW
d0cd7425
PA
1517 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1518 default 64
1519 range 4 640
8f9ca475 1520 ---help---
d0cd7425
PA
1521 Specify the amount of low memory to reserve for the BIOS.
1522
1523 The first page contains BIOS data structures that the kernel
1524 must not use, so that page must always be reserved.
1525
1526 By default we reserve the first 64K of physical RAM, as a
1527 number of BIOSes are known to corrupt that memory range
1528 during events such as suspend/resume or monitor cable
1529 insertion, so it must not be used by the kernel.
fc381519 1530
d0cd7425
PA
1531 You can set this to 4 if you are absolutely sure that you
1532 trust the BIOS to get all its memory reservations and usages
1533 right. If you know your BIOS have problems beyond the
1534 default 64K area, you can set this to 640 to avoid using the
1535 entire low memory range.
fc381519 1536
d0cd7425
PA
1537 If you have doubts about the BIOS (e.g. suspend/resume does
1538 not work or there's kernel crashes after certain hardware
1539 hotplug events) then you might want to enable
1540 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1541 typical corruption patterns.
fc381519 1542
d0cd7425 1543 Leave this to the default value of 64 if you are unsure.
fc381519 1544
506f1d07
SR
1545config MATH_EMULATION
1546 bool
a5b9e5a2 1547 depends on MODIFY_LDT_SYSCALL
506f1d07
SR
1548 prompt "Math emulation" if X86_32
1549 ---help---
1550 Linux can emulate a math coprocessor (used for floating point
1551 operations) if you don't have one. 486DX and Pentium processors have
1552 a math coprocessor built in, 486SX and 386 do not, unless you added
1553 a 487DX or 387, respectively. (The messages during boot time can
1554 give you some hints here ["man dmesg"].) Everyone needs either a
1555 coprocessor or this emulation.
1556
1557 If you don't have a math coprocessor, you need to say Y here; if you
1558 say Y here even though you have a coprocessor, the coprocessor will
1559 be used nevertheless. (This behavior can be changed with the kernel
1560 command line option "no387", which comes handy if your coprocessor
1561 is broken. Try "man bootparam" or see the documentation of your boot
1562 loader (lilo or loadlin) about how to pass options to the kernel at
1563 boot time.) This means that it is a good idea to say Y here if you
1564 intend to use this kernel on different machines.
1565
1566 More information about the internals of the Linux math coprocessor
1567 emulation can be found in <file:arch/x86/math-emu/README>.
1568
1569 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1570 kernel, it won't hurt.
1571
1572config MTRR
6fc108a0 1573 def_bool y
6a108a14 1574 prompt "MTRR (Memory Type Range Register) support" if EXPERT
506f1d07
SR
1575 ---help---
1576 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1577 the Memory Type Range Registers (MTRRs) may be used to control
1578 processor access to memory ranges. This is most useful if you have
1579 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1580 allows bus write transfers to be combined into a larger transfer
1581 before bursting over the PCI/AGP bus. This can increase performance
1582 of image write operations 2.5 times or more. Saying Y here creates a
1583 /proc/mtrr file which may be used to manipulate your processor's
1584 MTRRs. Typically the X server should use this.
1585
1586 This code has a reasonably generic interface so that similar
1587 control registers on other processors can be easily supported
1588 as well:
1589
1590 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1591 Registers (ARRs) which provide a similar functionality to MTRRs. For
1592 these, the ARRs are used to emulate the MTRRs.
1593 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1594 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1595 write-combining. All of these processors are supported by this code
1596 and it makes sense to say Y here if you have one of them.
1597
1598 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1599 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1600 can lead to all sorts of problems, so it's good to say Y here.
1601
1602 You can safely say Y even if your machine doesn't have MTRRs, you'll
1603 just add about 9 KB to your kernel.
1604
7225e751 1605 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1606
95ffa243 1607config MTRR_SANITIZER
2ffb3501 1608 def_bool y
95ffa243
YL
1609 prompt "MTRR cleanup support"
1610 depends on MTRR
8f9ca475 1611 ---help---
aba3728c
TG
1612 Convert MTRR layout from continuous to discrete, so X drivers can
1613 add writeback entries.
95ffa243 1614
aba3728c 1615 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1616 The largest mtrr entry size for a continuous block can be set with
aba3728c 1617 mtrr_chunk_size.
95ffa243 1618
2ffb3501 1619 If unsure, say Y.
95ffa243
YL
1620
1621config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1622 int "MTRR cleanup enable value (0-1)"
1623 range 0 1
1624 default "0"
95ffa243 1625 depends on MTRR_SANITIZER
8f9ca475 1626 ---help---
f5098d62 1627 Enable mtrr cleanup default value
95ffa243 1628
12031a62
YL
1629config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1630 int "MTRR cleanup spare reg num (0-7)"
1631 range 0 7
1632 default "1"
1633 depends on MTRR_SANITIZER
8f9ca475 1634 ---help---
12031a62 1635 mtrr cleanup spare entries default, it can be changed via
aba3728c 1636 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1637
2e5d9c85 1638config X86_PAT
6fc108a0 1639 def_bool y
6a108a14 1640 prompt "x86 PAT support" if EXPERT
2a8a2719 1641 depends on MTRR
8f9ca475 1642 ---help---
2e5d9c85 1643 Use PAT attributes to setup page level cache control.
042b78e4 1644
2e5d9c85 1645 PATs are the modern equivalents of MTRRs and are much more
1646 flexible than MTRRs.
1647
1648 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1649 spontaneous reboots) or a non-working video driver.
2e5d9c85 1650
1651 If unsure, say Y.
1652
46cf98cd
VP
1653config ARCH_USES_PG_UNCACHED
1654 def_bool y
1655 depends on X86_PAT
1656
628c6246
PA
1657config ARCH_RANDOM
1658 def_bool y
1659 prompt "x86 architectural random number generator" if EXPERT
1660 ---help---
1661 Enable the x86 architectural RDRAND instruction
1662 (Intel Bull Mountain technology) to generate random numbers.
1663 If supported, this is a high bandwidth, cryptographically
1664 secure hardware random number generator.
1665
51ae4a2d
PA
1666config X86_SMAP
1667 def_bool y
1668 prompt "Supervisor Mode Access Prevention" if EXPERT
1669 ---help---
1670 Supervisor Mode Access Prevention (SMAP) is a security
1671 feature in newer Intel processors. There is a small
1672 performance cost if this enabled and turned on; there is
1673 also a small increase in the kernel size if this is enabled.
1674
1675 If unsure, say Y.
1676
72e9b5fe
DH
1677config X86_INTEL_MPX
1678 prompt "Intel MPX (Memory Protection Extensions)"
1679 def_bool n
1680 depends on CPU_SUP_INTEL
1681 ---help---
1682 MPX provides hardware features that can be used in
1683 conjunction with compiler-instrumented code to check
1684 memory references. It is designed to detect buffer
1685 overflow or underflow bugs.
1686
1687 This option enables running applications which are
1688 instrumented or otherwise use MPX. It does not use MPX
1689 itself inside the kernel or to protect the kernel
1690 against bad memory references.
1691
1692 Enabling this option will make the kernel larger:
1693 ~8k of kernel text and 36 bytes of data on a 64-bit
1694 defconfig. It adds a long to the 'mm_struct' which
1695 will increase the kernel memory overhead of each
1696 process and adds some branches to paths used during
1697 exec() and munmap().
1698
1699 For details, see Documentation/x86/intel_mpx.txt
1700
1701 If unsure, say N.
1702
506f1d07 1703config EFI
9ba16087 1704 bool "EFI runtime service support"
5b83683f 1705 depends on ACPI
f6ce5002 1706 select UCS2_STRING
022ee6c5 1707 select EFI_RUNTIME_WRAPPERS
506f1d07 1708 ---help---
8f9ca475
IM
1709 This enables the kernel to use EFI runtime services that are
1710 available (such as the EFI variable services).
506f1d07 1711
8f9ca475
IM
1712 This option is only useful on systems that have EFI firmware.
1713 In addition, you should use the latest ELILO loader available
1714 at <http://elilo.sourceforge.net> in order to take advantage
1715 of EFI runtime services. However, even with this option, the
1716 resultant kernel should continue to boot on existing non-EFI
1717 platforms.
506f1d07 1718
291f3632
MF
1719config EFI_STUB
1720 bool "EFI stub support"
b16d8c23 1721 depends on EFI && !X86_USE_3DNOW
7b2a583a 1722 select RELOCATABLE
291f3632
MF
1723 ---help---
1724 This kernel feature allows a bzImage to be loaded directly
1725 by EFI firmware without the use of a bootloader.
1726
4172fe2f 1727 See Documentation/efi-stub.txt for more information.
0c759662 1728
7d453eee
MF
1729config EFI_MIXED
1730 bool "EFI mixed-mode support"
1731 depends on EFI_STUB && X86_64
1732 ---help---
1733 Enabling this feature allows a 64-bit kernel to be booted
1734 on a 32-bit firmware, provided that your CPU supports 64-bit
1735 mode.
1736
1737 Note that it is not possible to boot a mixed-mode enabled
1738 kernel via the EFI boot stub - a bootloader that supports
1739 the EFI handover protocol must be used.
1740
1741 If unsure, say N.
1742
506f1d07 1743config SECCOMP
3c2362e6
HH
1744 def_bool y
1745 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1746 ---help---
506f1d07
SR
1747 This kernel feature is useful for number crunching applications
1748 that may need to compute untrusted bytecode during their
1749 execution. By using pipes or other transports made available to
1750 the process as file descriptors supporting the read/write
1751 syscalls, it's possible to isolate those applications in
1752 their own address space using seccomp. Once seccomp is
9c0bbee8 1753 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1754 and the task is only allowed to execute a few safe syscalls
1755 defined by each seccomp mode.
1756
1757 If unsure, say Y. Only embedded should say N here.
1758
506f1d07
SR
1759source kernel/Kconfig.hz
1760
1761config KEXEC
1762 bool "kexec system call"
2965faa5 1763 select KEXEC_CORE
8f9ca475 1764 ---help---
506f1d07
SR
1765 kexec is a system call that implements the ability to shutdown your
1766 current kernel, and to start another kernel. It is like a reboot
1767 but it is independent of the system firmware. And like a reboot
1768 you can start any kernel with it, not just Linux.
1769
1770 The name comes from the similarity to the exec system call.
1771
1772 It is an ongoing process to be certain the hardware in a machine
1773 is properly shutdown, so do not be surprised if this code does not
bf220695
GU
1774 initially work for you. As of this writing the exact hardware
1775 interface is strongly in flux, so no good recommendation can be
1776 made.
506f1d07 1777
74ca317c
VG
1778config KEXEC_FILE
1779 bool "kexec file based system call"
2965faa5 1780 select KEXEC_CORE
74ca317c 1781 select BUILD_BIN2C
74ca317c
VG
1782 depends on X86_64
1783 depends on CRYPTO=y
1784 depends on CRYPTO_SHA256=y
1785 ---help---
1786 This is new version of kexec system call. This system call is
1787 file based and takes file descriptors as system call argument
1788 for kernel and initramfs as opposed to list of segments as
1789 accepted by previous system call.
1790
8e7d8381
VG
1791config KEXEC_VERIFY_SIG
1792 bool "Verify kernel signature during kexec_file_load() syscall"
74ca317c 1793 depends on KEXEC_FILE
8e7d8381
VG
1794 ---help---
1795 This option makes kernel signature verification mandatory for
d8eb8940
BP
1796 the kexec_file_load() syscall.
1797
1798 In addition to that option, you need to enable signature
1799 verification for the corresponding kernel image type being
1800 loaded in order for this to work.
8e7d8381
VG
1801
1802config KEXEC_BZIMAGE_VERIFY_SIG
1803 bool "Enable bzImage signature verification support"
1804 depends on KEXEC_VERIFY_SIG
1805 depends on SIGNED_PE_FILE_VERIFICATION
1806 select SYSTEM_TRUSTED_KEYRING
1807 ---help---
1808 Enable bzImage signature verification support.
1809
506f1d07 1810config CRASH_DUMP
04b69447 1811 bool "kernel crash dumps"
506f1d07 1812 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1813 ---help---
506f1d07
SR
1814 Generate crash dump after being started by kexec.
1815 This should be normally only set in special crash dump kernels
1816 which are loaded in the main kernel with kexec-tools into
1817 a specially reserved region and then later executed after
1818 a crash by kdump/kexec. The crash dump kernel must be compiled
1819 to a memory address not used by the main kernel or BIOS using
1820 PHYSICAL_START, or it must be built as a relocatable image
1821 (CONFIG_RELOCATABLE=y).
1822 For more details see Documentation/kdump/kdump.txt
1823
3ab83521 1824config KEXEC_JUMP
6ea30386 1825 bool "kexec jump"
fee7b0d8 1826 depends on KEXEC && HIBERNATION
8f9ca475 1827 ---help---
89081d17
HY
1828 Jump between original kernel and kexeced kernel and invoke
1829 code in physical address mode via KEXEC
3ab83521 1830
506f1d07 1831config PHYSICAL_START
6a108a14 1832 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
ceefccc9 1833 default "0x1000000"
8f9ca475 1834 ---help---
506f1d07
SR
1835 This gives the physical address where the kernel is loaded.
1836
1837 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1838 bzImage will decompress itself to above physical address and
1839 run from there. Otherwise, bzImage will run from the address where
1840 it has been loaded by the boot loader and will ignore above physical
1841 address.
1842
1843 In normal kdump cases one does not have to set/change this option
1844 as now bzImage can be compiled as a completely relocatable image
1845 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1846 address. This option is mainly useful for the folks who don't want
1847 to use a bzImage for capturing the crash dump and want to use a
1848 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1849 to be specifically compiled to run from a specific memory area
1850 (normally a reserved region) and this option comes handy.
1851
ceefccc9
PA
1852 So if you are using bzImage for capturing the crash dump,
1853 leave the value here unchanged to 0x1000000 and set
1854 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1855 for capturing the crash dump change this value to start of
1856 the reserved region. In other words, it can be set based on
1857 the "X" value as specified in the "crashkernel=YM@XM"
1858 command line boot parameter passed to the panic-ed
1859 kernel. Please take a look at Documentation/kdump/kdump.txt
1860 for more details about crash dumps.
506f1d07
SR
1861
1862 Usage of bzImage for capturing the crash dump is recommended as
1863 one does not have to build two kernels. Same kernel can be used
1864 as production kernel and capture kernel. Above option should have
1865 gone away after relocatable bzImage support is introduced. But it
1866 is present because there are users out there who continue to use
1867 vmlinux for dump capture. This option should go away down the
1868 line.
1869
1870 Don't change this unless you know what you are doing.
1871
1872config RELOCATABLE
26717808
PA
1873 bool "Build a relocatable kernel"
1874 default y
8f9ca475 1875 ---help---
506f1d07
SR
1876 This builds a kernel image that retains relocation information
1877 so it can be loaded someplace besides the default 1MB.
1878 The relocations tend to make the kernel binary about 10% larger,
1879 but are discarded at runtime.
1880
1881 One use is for the kexec on panic case where the recovery kernel
1882 must live at a different physical address than the primary
1883 kernel.
1884
1885 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1886 it has been loaded at and the compile time physical address
8ab3820f 1887 (CONFIG_PHYSICAL_START) is used as the minimum location.
506f1d07 1888
8ab3820f
KC
1889config RANDOMIZE_BASE
1890 bool "Randomize the address of the kernel image"
1891 depends on RELOCATABLE
8ab3820f
KC
1892 default n
1893 ---help---
1894 Randomizes the physical and virtual address at which the
1895 kernel image is decompressed, as a security feature that
1896 deters exploit attempts relying on knowledge of the location
1897 of kernel internals.
1898
a653f356
KC
1899 Entropy is generated using the RDRAND instruction if it is
1900 supported. If RDTSC is supported, it is used as well. If
1901 neither RDRAND nor RDTSC are supported, then randomness is
1902 read from the i8254 timer.
8ab3820f
KC
1903
1904 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
a653f356
KC
1905 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1906 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1907 minimum of 2MiB, only 10 bits of entropy is theoretically
1908 possible. At best, due to page table layouts, 64-bit can use
1909 9 bits of entropy and 32-bit uses 8 bits.
8ab3820f 1910
da2b6fb9
KC
1911 If unsure, say N.
1912
8ab3820f 1913config RANDOMIZE_BASE_MAX_OFFSET
da2b6fb9 1914 hex "Maximum kASLR offset allowed" if EXPERT
8ab3820f 1915 depends on RANDOMIZE_BASE
6145cfe3
KC
1916 range 0x0 0x20000000 if X86_32
1917 default "0x20000000" if X86_32
1918 range 0x0 0x40000000 if X86_64
1919 default "0x40000000" if X86_64
8ab3820f 1920 ---help---
da2b6fb9
KC
1921 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1922 memory is used to determine the maximal offset in bytes that will
1923 be applied to the kernel when kernel Address Space Layout
1924 Randomization (kASLR) is active. This must be a multiple of
1925 PHYSICAL_ALIGN.
1926
1927 On 32-bit this is limited to 512MiB by page table layouts. The
1928 default is 512MiB.
6145cfe3 1929
da2b6fb9
KC
1930 On 64-bit this is limited by how the kernel fixmap page table is
1931 positioned, so this cannot be larger than 1GiB currently. Without
1932 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1933 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1934 modules area will shrink to compensate, up to the current maximum
1935 1GiB to 1GiB split. The default is 1GiB.
6145cfe3 1936
da2b6fb9 1937 If unsure, leave at the default value.
8ab3820f
KC
1938
1939# Relocation on x86 needs some additional build support
845adf72
PA
1940config X86_NEED_RELOCS
1941 def_bool y
8ab3820f 1942 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
845adf72 1943
506f1d07 1944config PHYSICAL_ALIGN
a0215061 1945 hex "Alignment value to which kernel should be aligned"
8ab3820f 1946 default "0x200000"
a0215061
KC
1947 range 0x2000 0x1000000 if X86_32
1948 range 0x200000 0x1000000 if X86_64
8f9ca475 1949 ---help---
506f1d07
SR
1950 This value puts the alignment restrictions on physical address
1951 where kernel is loaded and run from. Kernel is compiled for an
1952 address which meets above alignment restriction.
1953
1954 If bootloader loads the kernel at a non-aligned address and
1955 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1956 address aligned to above value and run from there.
1957
1958 If bootloader loads the kernel at a non-aligned address and
1959 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1960 load address and decompress itself to the address it has been
1961 compiled for and run from there. The address for which kernel is
1962 compiled already meets above alignment restrictions. Hence the
1963 end result is that kernel runs from a physical address meeting
1964 above alignment restrictions.
1965
a0215061
KC
1966 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1967 this value must be a multiple of 0x200000.
1968
506f1d07
SR
1969 Don't change this unless you know what you are doing.
1970
1971config HOTPLUG_CPU
7c13e6a3 1972 bool "Support for hot-pluggable CPUs"
40b31360 1973 depends on SMP
506f1d07 1974 ---help---
7c13e6a3
DS
1975 Say Y here to allow turning CPUs off and on. CPUs can be
1976 controlled through /sys/devices/system/cpu.
1977 ( Note: power management support will enable this option
1978 automatically on SMP systems. )
1979 Say N if you want to disable CPU hotplug.
506f1d07 1980
80aa1dff
FY
1981config BOOTPARAM_HOTPLUG_CPU0
1982 bool "Set default setting of cpu0_hotpluggable"
1983 default n
2c922cd0 1984 depends on HOTPLUG_CPU
80aa1dff
FY
1985 ---help---
1986 Set whether default state of cpu0_hotpluggable is on or off.
1987
1988 Say Y here to enable CPU0 hotplug by default. If this switch
1989 is turned on, there is no need to give cpu0_hotplug kernel
1990 parameter and the CPU0 hotplug feature is enabled by default.
1991
1992 Please note: there are two known CPU0 dependencies if you want
1993 to enable the CPU0 hotplug feature either by this switch or by
1994 cpu0_hotplug kernel parameter.
1995
1996 First, resume from hibernate or suspend always starts from CPU0.
1997 So hibernate and suspend are prevented if CPU0 is offline.
1998
1999 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2000 offline if any interrupt can not migrate out of CPU0. There may
2001 be other CPU0 dependencies.
2002
2003 Please make sure the dependencies are under your control before
2004 you enable this feature.
2005
2006 Say N if you don't want to enable CPU0 hotplug feature by default.
2007 You still can enable the CPU0 hotplug feature at boot by kernel
2008 parameter cpu0_hotplug.
2009
a71c8bc5
FY
2010config DEBUG_HOTPLUG_CPU0
2011 def_bool n
2012 prompt "Debug CPU0 hotplug"
2c922cd0 2013 depends on HOTPLUG_CPU
a71c8bc5
FY
2014 ---help---
2015 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2016 soon as possible and boots up userspace with CPU0 offlined. User
2017 can online CPU0 back after boot time.
2018
2019 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2020 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2021 compilation or giving cpu0_hotplug kernel parameter at boot.
2022
2023 If unsure, say N.
2024
506f1d07 2025config COMPAT_VDSO
b0b49f26
AL
2026 def_bool n
2027 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
af65d648 2028 depends on X86_32 || IA32_EMULATION
8f9ca475 2029 ---help---
b0b49f26
AL
2030 Certain buggy versions of glibc will crash if they are
2031 presented with a 32-bit vDSO that is not mapped at the address
2032 indicated in its segment table.
e84446de 2033
b0b49f26
AL
2034 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2035 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2036 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2037 the only released version with the bug, but OpenSUSE 9
2038 contains a buggy "glibc 2.3.2".
506f1d07 2039
b0b49f26
AL
2040 The symptom of the bug is that everything crashes on startup, saying:
2041 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2042
2043 Saying Y here changes the default value of the vdso32 boot
2044 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2045 This works around the glibc bug but hurts performance.
2046
2047 If unsure, say N: if you are compiling your own kernel, you
2048 are unlikely to be using a buggy version of glibc.
506f1d07 2049
3dc33bd3
KC
2050choice
2051 prompt "vsyscall table for legacy applications"
2052 depends on X86_64
2053 default LEGACY_VSYSCALL_EMULATE
2054 help
2055 Legacy user code that does not know how to find the vDSO expects
2056 to be able to issue three syscalls by calling fixed addresses in
2057 kernel space. Since this location is not randomized with ASLR,
2058 it can be used to assist security vulnerability exploitation.
2059
2060 This setting can be changed at boot time via the kernel command
2061 line parameter vsyscall=[native|emulate|none].
2062
2063 On a system with recent enough glibc (2.14 or newer) and no
2064 static binaries, you can say None without a performance penalty
2065 to improve security.
2066
2067 If unsure, select "Emulate".
2068
2069 config LEGACY_VSYSCALL_NATIVE
2070 bool "Native"
2071 help
2072 Actual executable code is located in the fixed vsyscall
2073 address mapping, implementing time() efficiently. Since
2074 this makes the mapping executable, it can be used during
2075 security vulnerability exploitation (traditionally as
2076 ROP gadgets). This configuration is not recommended.
2077
2078 config LEGACY_VSYSCALL_EMULATE
2079 bool "Emulate"
2080 help
2081 The kernel traps and emulates calls into the fixed
2082 vsyscall address mapping. This makes the mapping
2083 non-executable, but it still contains known contents,
2084 which could be used in certain rare security vulnerability
2085 exploits. This configuration is recommended when userspace
2086 still uses the vsyscall area.
2087
2088 config LEGACY_VSYSCALL_NONE
2089 bool "None"
2090 help
2091 There will be no vsyscall mapping at all. This will
2092 eliminate any risk of ASLR bypass due to the vsyscall
2093 fixed address mapping. Attempts to use the vsyscalls
2094 will be reported to dmesg, so that either old or
2095 malicious userspace programs can be identified.
2096
2097endchoice
2098
516cbf37
TB
2099config CMDLINE_BOOL
2100 bool "Built-in kernel command line"
8f9ca475 2101 ---help---
516cbf37
TB
2102 Allow for specifying boot arguments to the kernel at
2103 build time. On some systems (e.g. embedded ones), it is
2104 necessary or convenient to provide some or all of the
2105 kernel boot arguments with the kernel itself (that is,
2106 to not rely on the boot loader to provide them.)
2107
2108 To compile command line arguments into the kernel,
2109 set this option to 'Y', then fill in the
69711ca1 2110 boot arguments in CONFIG_CMDLINE.
516cbf37
TB
2111
2112 Systems with fully functional boot loaders (i.e. non-embedded)
2113 should leave this option set to 'N'.
2114
2115config CMDLINE
2116 string "Built-in kernel command string"
2117 depends on CMDLINE_BOOL
2118 default ""
8f9ca475 2119 ---help---
516cbf37
TB
2120 Enter arguments here that should be compiled into the kernel
2121 image and used at boot time. If the boot loader provides a
2122 command line at boot time, it is appended to this string to
2123 form the full kernel command line, when the system boots.
2124
2125 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2126 change this behavior.
2127
2128 In most cases, the command line (whether built-in or provided
2129 by the boot loader) should specify the device for the root
2130 file system.
2131
2132config CMDLINE_OVERRIDE
2133 bool "Built-in command line overrides boot loader arguments"
516cbf37 2134 depends on CMDLINE_BOOL
8f9ca475 2135 ---help---
516cbf37
TB
2136 Set this option to 'Y' to have the kernel ignore the boot loader
2137 command line, and use ONLY the built-in command line.
2138
2139 This is used to work around broken boot loaders. This should
2140 be set to 'N' under normal conditions.
2141
a5b9e5a2
AL
2142config MODIFY_LDT_SYSCALL
2143 bool "Enable the LDT (local descriptor table)" if EXPERT
2144 default y
2145 ---help---
2146 Linux can allow user programs to install a per-process x86
2147 Local Descriptor Table (LDT) using the modify_ldt(2) system
2148 call. This is required to run 16-bit or segmented code such as
2149 DOSEMU or some Wine programs. It is also used by some very old
2150 threading libraries.
2151
2152 Enabling this feature adds a small amount of overhead to
2153 context switches and increases the low-level kernel attack
2154 surface. Disabling it removes the modify_ldt(2) system call.
2155
2156 Saying 'N' here may make sense for embedded or server kernels.
2157
b700e7f0
SJ
2158source "kernel/livepatch/Kconfig"
2159
506f1d07
SR
2160endmenu
2161
2162config ARCH_ENABLE_MEMORY_HOTPLUG
2163 def_bool y
2164 depends on X86_64 || (X86_32 && HIGHMEM)
2165
35551053
GH
2166config ARCH_ENABLE_MEMORY_HOTREMOVE
2167 def_bool y
2168 depends on MEMORY_HOTPLUG
2169
e534c7c5 2170config USE_PERCPU_NUMA_NODE_ID
645a7919 2171 def_bool y
e534c7c5
LS
2172 depends on NUMA
2173
9491846f
KS
2174config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2175 def_bool y
2176 depends on X86_64 || X86_PAE
2177
c177c81e
NH
2178config ARCH_ENABLE_HUGEPAGE_MIGRATION
2179 def_bool y
2180 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2181
da85f865 2182menu "Power management and ACPI options"
e279b6c1
SR
2183
2184config ARCH_HIBERNATION_HEADER
3c2362e6 2185 def_bool y
e279b6c1 2186 depends on X86_64 && HIBERNATION
e279b6c1
SR
2187
2188source "kernel/power/Kconfig"
2189
2190source "drivers/acpi/Kconfig"
2191
efafc8b2
FT
2192source "drivers/sfi/Kconfig"
2193
a6b68076 2194config X86_APM_BOOT
6fc108a0 2195 def_bool y
282e5aab 2196 depends on APM
a6b68076 2197
e279b6c1
SR
2198menuconfig APM
2199 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 2200 depends on X86_32 && PM_SLEEP
e279b6c1
SR
2201 ---help---
2202 APM is a BIOS specification for saving power using several different
2203 techniques. This is mostly useful for battery powered laptops with
2204 APM compliant BIOSes. If you say Y here, the system time will be
2205 reset after a RESUME operation, the /proc/apm device will provide
2206 battery status information, and user-space programs will receive
2207 notification of APM "events" (e.g. battery status change).
2208
2209 If you select "Y" here, you can disable actual use of the APM
2210 BIOS by passing the "apm=off" option to the kernel at boot time.
2211
2212 Note that the APM support is almost completely disabled for
2213 machines with more than one CPU.
2214
2215 In order to use APM, you will need supporting software. For location
2dc98fd3
MW
2216 and more information, read <file:Documentation/power/apm-acpi.txt>
2217 and the Battery Powered Linux mini-HOWTO, available from
e279b6c1
SR
2218 <http://www.tldp.org/docs.html#howto>.
2219
2220 This driver does not spin down disk drives (see the hdparm(8)
2221 manpage ("man 8 hdparm") for that), and it doesn't turn off
2222 VESA-compliant "green" monitors.
2223
2224 This driver does not support the TI 4000M TravelMate and the ACER
2225 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2226 desktop machines also don't have compliant BIOSes, and this driver
2227 may cause those machines to panic during the boot phase.
2228
2229 Generally, if you don't have a battery in your machine, there isn't
2230 much point in using this driver and you should say N. If you get
2231 random kernel OOPSes or reboots that don't seem to be related to
2232 anything, try disabling/enabling this option (or disabling/enabling
2233 APM in your BIOS).
2234
2235 Some other things you should try when experiencing seemingly random,
2236 "weird" problems:
2237
2238 1) make sure that you have enough swap space and that it is
2239 enabled.
2240 2) pass the "no-hlt" option to the kernel
2241 3) switch on floating point emulation in the kernel and pass
2242 the "no387" option to the kernel
2243 4) pass the "floppy=nodma" option to the kernel
2244 5) pass the "mem=4M" option to the kernel (thereby disabling
2245 all but the first 4 MB of RAM)
2246 6) make sure that the CPU is not over clocked.
2247 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2248 8) disable the cache from your BIOS settings
2249 9) install a fan for the video card or exchange video RAM
2250 10) install a better fan for the CPU
2251 11) exchange RAM chips
2252 12) exchange the motherboard.
2253
2254 To compile this driver as a module, choose M here: the
2255 module will be called apm.
2256
2257if APM
2258
2259config APM_IGNORE_USER_SUSPEND
2260 bool "Ignore USER SUSPEND"
8f9ca475 2261 ---help---
e279b6c1
SR
2262 This option will ignore USER SUSPEND requests. On machines with a
2263 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2264 series notebooks, it is necessary to say Y because of a BIOS bug.
2265
2266config APM_DO_ENABLE
2267 bool "Enable PM at boot time"
2268 ---help---
2269 Enable APM features at boot time. From page 36 of the APM BIOS
2270 specification: "When disabled, the APM BIOS does not automatically
2271 power manage devices, enter the Standby State, enter the Suspend
2272 State, or take power saving steps in response to CPU Idle calls."
2273 This driver will make CPU Idle calls when Linux is idle (unless this
2274 feature is turned off -- see "Do CPU IDLE calls", below). This
2275 should always save battery power, but more complicated APM features
2276 will be dependent on your BIOS implementation. You may need to turn
2277 this option off if your computer hangs at boot time when using APM
2278 support, or if it beeps continuously instead of suspending. Turn
2279 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2280 T400CDT. This is off by default since most machines do fine without
2281 this feature.
2282
2283config APM_CPU_IDLE
dd8af076 2284 depends on CPU_IDLE
e279b6c1 2285 bool "Make CPU Idle calls when idle"
8f9ca475 2286 ---help---
e279b6c1
SR
2287 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2288 On some machines, this can activate improved power savings, such as
2289 a slowed CPU clock rate, when the machine is idle. These idle calls
2290 are made after the idle loop has run for some length of time (e.g.,
2291 333 mS). On some machines, this will cause a hang at boot time or
2292 whenever the CPU becomes idle. (On machines with more than one CPU,
2293 this option does nothing.)
2294
2295config APM_DISPLAY_BLANK
2296 bool "Enable console blanking using APM"
8f9ca475 2297 ---help---
e279b6c1
SR
2298 Enable console blanking using the APM. Some laptops can use this to
2299 turn off the LCD backlight when the screen blanker of the Linux
2300 virtual console blanks the screen. Note that this is only used by
2301 the virtual console screen blanker, and won't turn off the backlight
2302 when using the X Window system. This also doesn't have anything to
2303 do with your VESA-compliant power-saving monitor. Further, this
2304 option doesn't work for all laptops -- it might not turn off your
2305 backlight at all, or it might print a lot of errors to the console,
2306 especially if you are using gpm.
2307
2308config APM_ALLOW_INTS
2309 bool "Allow interrupts during APM BIOS calls"
8f9ca475 2310 ---help---
e279b6c1
SR
2311 Normally we disable external interrupts while we are making calls to
2312 the APM BIOS as a measure to lessen the effects of a badly behaving
2313 BIOS implementation. The BIOS should reenable interrupts if it
2314 needs to. Unfortunately, some BIOSes do not -- especially those in
2315 many of the newer IBM Thinkpads. If you experience hangs when you
2316 suspend, try setting this to Y. Otherwise, say N.
2317
e279b6c1
SR
2318endif # APM
2319
bb0a56ec 2320source "drivers/cpufreq/Kconfig"
e279b6c1
SR
2321
2322source "drivers/cpuidle/Kconfig"
2323
27471fdb
AH
2324source "drivers/idle/Kconfig"
2325
e279b6c1
SR
2326endmenu
2327
2328
2329menu "Bus options (PCI etc.)"
2330
2331config PCI
1ac97018 2332 bool "PCI support"
1c858087 2333 default y
8f9ca475 2334 ---help---
e279b6c1
SR
2335 Find out whether you have a PCI motherboard. PCI is the name of a
2336 bus system, i.e. the way the CPU talks to the other stuff inside
2337 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2338 VESA. If you have PCI, say Y, otherwise N.
2339
e279b6c1
SR
2340choice
2341 prompt "PCI access mode"
efefa6f6 2342 depends on X86_32 && PCI
e279b6c1
SR
2343 default PCI_GOANY
2344 ---help---
2345 On PCI systems, the BIOS can be used to detect the PCI devices and
2346 determine their configuration. However, some old PCI motherboards
2347 have BIOS bugs and may crash if this is done. Also, some embedded
2348 PCI-based systems don't have any BIOS at all. Linux can also try to
2349 detect the PCI hardware directly without using the BIOS.
2350
2351 With this option, you can specify how Linux should detect the
2352 PCI devices. If you choose "BIOS", the BIOS will be used,
2353 if you choose "Direct", the BIOS won't be used, and if you
2354 choose "MMConfig", then PCI Express MMCONFIG will be used.
2355 If you choose "Any", the kernel will try MMCONFIG, then the
2356 direct access method and falls back to the BIOS if that doesn't
2357 work. If unsure, go with the default, which is "Any".
2358
2359config PCI_GOBIOS
2360 bool "BIOS"
2361
2362config PCI_GOMMCONFIG
2363 bool "MMConfig"
2364
2365config PCI_GODIRECT
2366 bool "Direct"
2367
3ef0e1f8 2368config PCI_GOOLPC
76fb6570 2369 bool "OLPC XO-1"
3ef0e1f8
AS
2370 depends on OLPC
2371
2bdd1b03
AS
2372config PCI_GOANY
2373 bool "Any"
2374
e279b6c1
SR
2375endchoice
2376
2377config PCI_BIOS
3c2362e6 2378 def_bool y
efefa6f6 2379 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
e279b6c1
SR
2380
2381# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2382config PCI_DIRECT
3c2362e6 2383 def_bool y
0aba496f 2384 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
e279b6c1
SR
2385
2386config PCI_MMCONFIG
3c2362e6 2387 def_bool y
5f0db7a2 2388 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 2389
3ef0e1f8 2390config PCI_OLPC
2bdd1b03
AS
2391 def_bool y
2392 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 2393
b5401a96
AN
2394config PCI_XEN
2395 def_bool y
2396 depends on PCI && XEN
2397 select SWIOTLB_XEN
2398
e279b6c1 2399config PCI_DOMAINS
3c2362e6 2400 def_bool y
e279b6c1 2401 depends on PCI
e279b6c1
SR
2402
2403config PCI_MMCONFIG
2404 bool "Support mmconfig PCI config space access"
2405 depends on X86_64 && PCI && ACPI
2406
3f6ea84a 2407config PCI_CNB20LE_QUIRK
6a108a14 2408 bool "Read CNB20LE Host Bridge Windows" if EXPERT
6ea30386 2409 depends on PCI
3f6ea84a
IS
2410 help
2411 Read the PCI windows out of the CNB20LE host bridge. This allows
2412 PCI hotplug to work on systems with the CNB20LE chipset which do
2413 not have ACPI.
2414
64a5fed6
BH
2415 There's no public spec for this chipset, and this functionality
2416 is known to be incomplete.
2417
2418 You should say N unless you know you need this.
2419
e279b6c1
SR
2420source "drivers/pci/pcie/Kconfig"
2421
2422source "drivers/pci/Kconfig"
2423
1c00f016 2424# x86_64 have no ISA slots, but can have ISA-style DMA.
e279b6c1 2425config ISA_DMA_API
1c00f016
DR
2426 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2427 default y
2428 help
2429 Enables ISA-style DMA support for devices requiring such controllers.
2430 If unsure, say Y.
e279b6c1
SR
2431
2432if X86_32
2433
2434config ISA
2435 bool "ISA support"
8f9ca475 2436 ---help---
e279b6c1
SR
2437 Find out whether you have ISA slots on your motherboard. ISA is the
2438 name of a bus system, i.e. the way the CPU talks to the other stuff
2439 inside your box. Other bus systems are PCI, EISA, MicroChannel
2440 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2441 newer boards don't support it. If you have ISA, say Y, otherwise N.
2442
2443config EISA
2444 bool "EISA support"
2445 depends on ISA
2446 ---help---
2447 The Extended Industry Standard Architecture (EISA) bus was
2448 developed as an open alternative to the IBM MicroChannel bus.
2449
2450 The EISA bus provided some of the features of the IBM MicroChannel
2451 bus while maintaining backward compatibility with cards made for
2452 the older ISA bus. The EISA bus saw limited use between 1988 and
2453 1995 when it was made obsolete by the PCI bus.
2454
2455 Say Y here if you are building a kernel for an EISA-based machine.
2456
2457 Otherwise, say N.
2458
2459source "drivers/eisa/Kconfig"
2460
e279b6c1
SR
2461config SCx200
2462 tristate "NatSemi SCx200 support"
8f9ca475 2463 ---help---
e279b6c1
SR
2464 This provides basic support for National Semiconductor's
2465 (now AMD's) Geode processors. The driver probes for the
2466 PCI-IDs of several on-chip devices, so its a good dependency
2467 for other scx200_* drivers.
2468
2469 If compiled as a module, the driver is named scx200.
2470
2471config SCx200HR_TIMER
2472 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
592913ec 2473 depends on SCx200
e279b6c1 2474 default y
8f9ca475 2475 ---help---
e279b6c1
SR
2476 This driver provides a clocksource built upon the on-chip
2477 27MHz high-resolution timer. Its also a workaround for
2478 NSC Geode SC-1100's buggy TSC, which loses time when the
2479 processor goes idle (as is done by the scheduler). The
2480 other workaround is idle=poll boot option.
2481
3ef0e1f8
AS
2482config OLPC
2483 bool "One Laptop Per Child support"
54008979 2484 depends on !X86_PAE
3c554946 2485 select GPIOLIB
dc3119e7 2486 select OF
45bb1674 2487 select OF_PROMTREE
b4e51854 2488 select IRQ_DOMAIN
8f9ca475 2489 ---help---
3ef0e1f8
AS
2490 Add support for detecting the unique features of the OLPC
2491 XO hardware.
2492
a3128588
DD
2493config OLPC_XO1_PM
2494 bool "OLPC XO-1 Power Management"
97c4cb71 2495 depends on OLPC && MFD_CS5535 && PM_SLEEP
a3128588 2496 select MFD_CORE
bf1ebf00 2497 ---help---
97c4cb71 2498 Add support for poweroff and suspend of the OLPC XO-1 laptop.
bf1ebf00 2499
cfee9597
DD
2500config OLPC_XO1_RTC
2501 bool "OLPC XO-1 Real Time Clock"
2502 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2503 ---help---
2504 Add support for the XO-1 real time clock, which can be used as a
2505 programmable wakeup source.
2506
7feda8e9
DD
2507config OLPC_XO1_SCI
2508 bool "OLPC XO-1 SCI extras"
d8d01a63 2509 depends on OLPC && OLPC_XO1_PM
ed8e47fe 2510 depends on INPUT=y
d8d01a63 2511 select POWER_SUPPLY
7feda8e9
DD
2512 select GPIO_CS5535
2513 select MFD_CORE
2514 ---help---
2515 Add support for SCI-based features of the OLPC XO-1 laptop:
7bc74b3d 2516 - EC-driven system wakeups
7feda8e9 2517 - Power button
7bc74b3d 2518 - Ebook switch
2cf2baea 2519 - Lid switch
e1040ac6
DD
2520 - AC adapter status updates
2521 - Battery status updates
7feda8e9 2522
a0f30f59
DD
2523config OLPC_XO15_SCI
2524 bool "OLPC XO-1.5 SCI extras"
d8d01a63
DD
2525 depends on OLPC && ACPI
2526 select POWER_SUPPLY
a0f30f59
DD
2527 ---help---
2528 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2529 - EC-driven system wakeups
2530 - AC adapter status updates
2531 - Battery status updates
bf1ebf00 2532
d4f3e350
EW
2533config ALIX
2534 bool "PCEngines ALIX System Support (LED setup)"
2535 select GPIOLIB
2536 ---help---
2537 This option enables system support for the PCEngines ALIX.
2538 At present this just sets up LEDs for GPIO control on
2539 ALIX2/3/6 boards. However, other system specific setup should
2540 get added here.
2541
2542 Note: You must still enable the drivers for GPIO and LED support
2543 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2544
2545 Note: You have to set alix.force=1 for boards with Award BIOS.
2546
da4e3302
PP
2547config NET5501
2548 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2549 select GPIOLIB
2550 ---help---
2551 This option enables system support for the Soekris Engineering net5501.
2552
3197059a
PP
2553config GEOS
2554 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2555 select GPIOLIB
2556 depends on DMI
2557 ---help---
2558 This option enables system support for the Traverse Technologies GEOS.
2559
7d029125
VD
2560config TS5500
2561 bool "Technologic Systems TS-5500 platform support"
2562 depends on MELAN
2563 select CHECK_SIGNATURE
2564 select NEW_LEDS
2565 select LEDS_CLASS
2566 ---help---
2567 This option enables system support for the Technologic Systems TS-5500.
2568
bc0120fd
SR
2569endif # X86_32
2570
23ac4ae8 2571config AMD_NB
e279b6c1 2572 def_bool y
0e152cd7 2573 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2574
2575source "drivers/pcmcia/Kconfig"
2576
2577source "drivers/pci/hotplug/Kconfig"
2578
388b78ad 2579config RAPIDIO
fdf90abc 2580 tristate "RapidIO support"
388b78ad
AB
2581 depends on PCI
2582 default n
2583 help
fdf90abc 2584 If enabled this option will include drivers and the core
388b78ad
AB
2585 infrastructure code to support RapidIO interconnect devices.
2586
2587source "drivers/rapidio/Kconfig"
2588
e3263ab3
DH
2589config X86_SYSFB
2590 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2591 help
2592 Firmwares often provide initial graphics framebuffers so the BIOS,
2593 bootloader or kernel can show basic video-output during boot for
2594 user-guidance and debugging. Historically, x86 used the VESA BIOS
2595 Extensions and EFI-framebuffers for this, which are mostly limited
2596 to x86.
2597 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2598 framebuffers so the new generic system-framebuffer drivers can be
2599 used on x86. If the framebuffer is not compatible with the generic
2600 modes, it is adverticed as fallback platform framebuffer so legacy
2601 drivers like efifb, vesafb and uvesafb can pick it up.
2602 If this option is not selected, all system framebuffers are always
2603 marked as fallback platform framebuffers as usual.
2604
2605 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2606 not be able to pick up generic system framebuffers if this option
2607 is selected. You are highly encouraged to enable simplefb as
2608 replacement if you select this option. simplefb can correctly deal
2609 with generic system framebuffers. But you should still keep vesafb
2610 and others enabled as fallback if a system framebuffer is
2611 incompatible with simplefb.
2612
2613 If unsure, say Y.
2614
e279b6c1
SR
2615endmenu
2616
2617
2618menu "Executable file formats / Emulations"
2619
2620source "fs/Kconfig.binfmt"
2621
2622config IA32_EMULATION
2623 bool "IA32 Emulation"
2624 depends on X86_64
d1603990 2625 select BINFMT_ELF
a97f52e6 2626 select COMPAT_BINFMT_ELF
3bead553 2627 select ARCH_WANT_OLD_COMPAT_IPC
8f9ca475 2628 ---help---
5fd92e65
L
2629 Include code to run legacy 32-bit programs under a
2630 64-bit kernel. You should likely turn this on, unless you're
2631 100% sure that you don't have any 32-bit programs left.
e279b6c1
SR
2632
2633config IA32_AOUT
8f9ca475
IM
2634 tristate "IA32 a.out support"
2635 depends on IA32_EMULATION
2636 ---help---
2637 Support old a.out binaries in the 32bit emulation.
e279b6c1 2638
0bf62763 2639config X86_X32
6ea30386 2640 bool "x32 ABI for 64-bit mode"
9b54050b 2641 depends on X86_64
5fd92e65
L
2642 ---help---
2643 Include code to run binaries for the x32 native 32-bit ABI
2644 for 64-bit processors. An x32 process gets access to the
2645 full 64-bit register file and wide data path while leaving
2646 pointers at 32 bits for smaller memory footprint.
2647
2648 You will need a recent binutils (2.22 or later) with
2649 elf32_x86_64 support enabled to compile a kernel with this
2650 option set.
2651
e279b6c1 2652config COMPAT
3c2362e6 2653 def_bool y
0bf62763 2654 depends on IA32_EMULATION || X86_X32
e279b6c1 2655
3120e25e 2656if COMPAT
e279b6c1 2657config COMPAT_FOR_U64_ALIGNMENT
3120e25e 2658 def_bool y
e279b6c1
SR
2659
2660config SYSVIPC_COMPAT
3c2362e6 2661 def_bool y
3120e25e 2662 depends on SYSVIPC
e279b6c1 2663
ee009e4a 2664config KEYS_COMPAT
3120e25e
JB
2665 def_bool y
2666 depends on KEYS
2667endif
ee009e4a 2668
e279b6c1
SR
2669endmenu
2670
2671
e5beae16
KP
2672config HAVE_ATOMIC_IOMAP
2673 def_bool y
2674 depends on X86_32
2675
4692d77f
AR
2676config X86_DEV_DMA_OPS
2677 bool
83125a3a 2678 depends on X86_64 || STA2X11
4692d77f 2679
f7219a53
AR
2680config X86_DMA_REMAP
2681 bool
83125a3a 2682 depends on STA2X11
f7219a53 2683
93e5eadd
LA
2684config PMC_ATOM
2685 def_bool y
2686 depends on PCI
2687
e279b6c1
SR
2688source "net/Kconfig"
2689
2690source "drivers/Kconfig"
2691
2692source "drivers/firmware/Kconfig"
2693
2694source "fs/Kconfig"
2695
e279b6c1
SR
2696source "arch/x86/Kconfig.debug"
2697
2698source "security/Kconfig"
2699
2700source "crypto/Kconfig"
2701
edf88417
AK
2702source "arch/x86/kvm/Kconfig"
2703
e279b6c1 2704source "lib/Kconfig"
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