Kconfig 68 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137113811391140114111421143114411451146114711481149115011511152115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188118911901191119211931194119511961197119811991200120112021203120412051206120712081209121012111212121312141215121612171218121912201221122212231224122512261227122812291230123112321233123412351236123712381239124012411242124312441245124612471248124912501251125212531254125512561257125812591260126112621263126412651266126712681269127012711272127312741275127612771278127912801281128212831284128512861287128812891290129112921293129412951296129712981299130013011302130313041305130613071308130913101311131213131314131513161317131813191320132113221323132413251326132713281329133013311332133313341335133613371338133913401341134213431344134513461347134813491350135113521353135413551356135713581359136013611362136313641365136613671368136913701371137213731374137513761377137813791380138113821383138413851386138713881389139013911392139313941395139613971398139914001401140214031404140514061407140814091410141114121413141414151416141714181419142014211422142314241425142614271428142914301431143214331434143514361437143814391440144114421443144414451446144714481449145014511452145314541455145614571458145914601461146214631464146514661467146814691470147114721473147414751476147714781479148014811482148314841485148614871488148914901491149214931494149514961497149814991500150115021503150415051506150715081509151015111512151315141515151615171518151915201521152215231524152515261527152815291530153115321533153415351536153715381539154015411542154315441545154615471548154915501551155215531554155515561557155815591560156115621563156415651566156715681569157015711572157315741575157615771578157915801581158215831584158515861587158815891590159115921593159415951596159715981599160016011602160316041605160616071608160916101611161216131614161516161617161816191620162116221623162416251626162716281629163016311632163316341635163616371638163916401641164216431644164516461647164816491650165116521653165416551656165716581659166016611662166316641665166616671668166916701671167216731674167516761677167816791680168116821683168416851686168716881689169016911692169316941695169616971698169917001701170217031704170517061707170817091710171117121713171417151716171717181719172017211722172317241725172617271728172917301731173217331734173517361737173817391740174117421743174417451746174717481749175017511752175317541755175617571758175917601761176217631764176517661767176817691770177117721773177417751776177717781779178017811782178317841785178617871788178917901791179217931794179517961797179817991800180118021803180418051806180718081809181018111812181318141815181618171818181918201821182218231824182518261827182818291830183118321833183418351836183718381839184018411842184318441845184618471848184918501851185218531854185518561857185818591860186118621863186418651866186718681869187018711872187318741875187618771878187918801881188218831884188518861887188818891890189118921893189418951896189718981899190019011902190319041905190619071908190919101911191219131914191519161917191819191920192119221923192419251926192719281929193019311932193319341935193619371938193919401941194219431944194519461947194819491950195119521953195419551956195719581959196019611962196319641965196619671968196919701971197219731974197519761977197819791980198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016201720182019202020212022202320242025202620272028202920302031203220332034203520362037203820392040204120422043204420452046204720482049205020512052205320542055205620572058205920602061206220632064206520662067206820692070207120722073207420752076207720782079208020812082208320842085208620872088208920902091209220932094209520962097209820992100210121022103210421052106210721082109211021112112211321142115211621172118211921202121212221232124212521262127212821292130213121322133213421352136
  1. # x86 configuration
  2. mainmenu "Linux Kernel Configuration for x86"
  3. # Select 32 or 64 bit
  4. config 64BIT
  5. bool "64-bit kernel" if ARCH = "x86"
  6. default ARCH = "x86_64"
  7. ---help---
  8. Say yes to build a 64-bit kernel - formerly known as x86_64
  9. Say no to build a 32-bit kernel - formerly known as i386
  10. config X86_32
  11. def_bool !64BIT
  12. config X86_64
  13. def_bool 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select HAVE_AOUT if X86_32
  18. select HAVE_READQ
  19. select HAVE_WRITEQ
  20. select HAVE_UNSTABLE_SCHED_CLOCK
  21. select HAVE_IDE
  22. select HAVE_OPROFILE
  23. select HAVE_PERF_EVENTS if (!M386 && !M486)
  24. select HAVE_IRQ_WORK
  25. select HAVE_IOREMAP_PROT
  26. select HAVE_KPROBES
  27. select ARCH_WANT_OPTIONAL_GPIOLIB
  28. select ARCH_WANT_FRAME_POINTERS
  29. select HAVE_DMA_ATTRS
  30. select HAVE_KRETPROBES
  31. select HAVE_OPTPROBES
  32. select HAVE_FTRACE_MCOUNT_RECORD
  33. select HAVE_C_RECORDMCOUNT
  34. select HAVE_DYNAMIC_FTRACE
  35. select HAVE_FUNCTION_TRACER
  36. select HAVE_FUNCTION_GRAPH_TRACER
  37. select HAVE_FUNCTION_GRAPH_FP_TEST
  38. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  39. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  40. select HAVE_SYSCALL_TRACEPOINTS
  41. select HAVE_KVM
  42. select HAVE_ARCH_KGDB
  43. select HAVE_ARCH_TRACEHOOK
  44. select HAVE_GENERIC_DMA_COHERENT if X86_32
  45. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  46. select USER_STACKTRACE_SUPPORT
  47. select HAVE_REGS_AND_STACK_ACCESS_API
  48. select HAVE_DMA_API_DEBUG
  49. select HAVE_KERNEL_GZIP
  50. select HAVE_KERNEL_BZIP2
  51. select HAVE_KERNEL_LZMA
  52. select HAVE_KERNEL_LZO
  53. select HAVE_HW_BREAKPOINT
  54. select HAVE_MIXED_BREAKPOINTS_REGS
  55. select PERF_EVENTS
  56. select HAVE_PERF_EVENTS_NMI
  57. select ANON_INODES
  58. select HAVE_ARCH_KMEMCHECK
  59. select HAVE_USER_RETURN_NOTIFIER
  60. select HAVE_ARCH_JUMP_LABEL
  61. select HAVE_TEXT_POKE_SMP
  62. select HAVE_GENERIC_HARDIRQS
  63. select HAVE_SPARSE_IRQ
  64. select GENERIC_IRQ_PROBE
  65. select GENERIC_PENDING_IRQ if SMP
  66. config INSTRUCTION_DECODER
  67. def_bool (KPROBES || PERF_EVENTS)
  68. config OUTPUT_FORMAT
  69. string
  70. default "elf32-i386" if X86_32
  71. default "elf64-x86-64" if X86_64
  72. config ARCH_DEFCONFIG
  73. string
  74. default "arch/x86/configs/i386_defconfig" if X86_32
  75. default "arch/x86/configs/x86_64_defconfig" if X86_64
  76. config GENERIC_CMOS_UPDATE
  77. def_bool y
  78. config CLOCKSOURCE_WATCHDOG
  79. def_bool y
  80. config GENERIC_CLOCKEVENTS
  81. def_bool y
  82. config GENERIC_CLOCKEVENTS_BROADCAST
  83. def_bool y
  84. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  85. config LOCKDEP_SUPPORT
  86. def_bool y
  87. config STACKTRACE_SUPPORT
  88. def_bool y
  89. config HAVE_LATENCYTOP_SUPPORT
  90. def_bool y
  91. config MMU
  92. def_bool y
  93. config ZONE_DMA
  94. def_bool y
  95. config SBUS
  96. bool
  97. config NEED_DMA_MAP_STATE
  98. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  99. config NEED_SG_DMA_LENGTH
  100. def_bool y
  101. config GENERIC_ISA_DMA
  102. def_bool y
  103. config GENERIC_IOMAP
  104. def_bool y
  105. config GENERIC_BUG
  106. def_bool y
  107. depends on BUG
  108. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  109. config GENERIC_BUG_RELATIVE_POINTERS
  110. bool
  111. config GENERIC_HWEIGHT
  112. def_bool y
  113. config GENERIC_GPIO
  114. bool
  115. config ARCH_MAY_HAVE_PC_FDC
  116. def_bool y
  117. config RWSEM_GENERIC_SPINLOCK
  118. def_bool !X86_XADD
  119. config RWSEM_XCHGADD_ALGORITHM
  120. def_bool X86_XADD
  121. config ARCH_HAS_CPU_IDLE_WAIT
  122. def_bool y
  123. config GENERIC_CALIBRATE_DELAY
  124. def_bool y
  125. config GENERIC_TIME_VSYSCALL
  126. bool
  127. default X86_64
  128. config ARCH_HAS_CPU_RELAX
  129. def_bool y
  130. config ARCH_HAS_DEFAULT_IDLE
  131. def_bool y
  132. config ARCH_HAS_CACHE_LINE_SIZE
  133. def_bool y
  134. config HAVE_SETUP_PER_CPU_AREA
  135. def_bool y
  136. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  137. def_bool y
  138. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  139. def_bool y
  140. config HAVE_CPUMASK_OF_CPU_MAP
  141. def_bool X86_64_SMP
  142. config ARCH_HIBERNATION_POSSIBLE
  143. def_bool y
  144. config ARCH_SUSPEND_POSSIBLE
  145. def_bool y
  146. config ZONE_DMA32
  147. bool
  148. default X86_64
  149. config ARCH_POPULATES_NODE_MAP
  150. def_bool y
  151. config AUDIT_ARCH
  152. bool
  153. default X86_64
  154. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  155. def_bool y
  156. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  157. def_bool y
  158. config HAVE_EARLY_RES
  159. def_bool y
  160. config HAVE_INTEL_TXT
  161. def_bool y
  162. depends on EXPERIMENTAL && DMAR && ACPI
  163. config USE_GENERIC_SMP_HELPERS
  164. def_bool y
  165. depends on SMP
  166. config X86_32_SMP
  167. def_bool y
  168. depends on X86_32 && SMP
  169. config X86_64_SMP
  170. def_bool y
  171. depends on X86_64 && SMP
  172. config X86_HT
  173. def_bool y
  174. depends on SMP
  175. config X86_TRAMPOLINE
  176. def_bool y
  177. depends on SMP || (64BIT && ACPI_SLEEP)
  178. config X86_32_LAZY_GS
  179. def_bool y
  180. depends on X86_32 && !CC_STACKPROTECTOR
  181. config ARCH_HWEIGHT_CFLAGS
  182. string
  183. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  184. 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
  185. config KTIME_SCALAR
  186. def_bool X86_32
  187. config ARCH_CPU_PROBE_RELEASE
  188. def_bool y
  189. depends on HOTPLUG_CPU
  190. source "init/Kconfig"
  191. source "kernel/Kconfig.freezer"
  192. menu "Processor type and features"
  193. source "kernel/time/Kconfig"
  194. config SMP
  195. bool "Symmetric multi-processing support"
  196. ---help---
  197. This enables support for systems with more than one CPU. If you have
  198. a system with only one CPU, like most personal computers, say N. If
  199. you have a system with more than one CPU, say Y.
  200. If you say N here, the kernel will run on single and multiprocessor
  201. machines, but will use only one CPU of a multiprocessor machine. If
  202. you say Y here, the kernel will run on many, but not all,
  203. singleprocessor machines. On a singleprocessor machine, the kernel
  204. will run faster if you say N here.
  205. Note that if you say Y here and choose architecture "586" or
  206. "Pentium" under "Processor family", the kernel will not work on 486
  207. architectures. Similarly, multiprocessor kernels for the "PPro"
  208. architecture may not work on all Pentium based boards.
  209. People using multiprocessor machines who say Y here should also say
  210. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  211. Management" code will be disabled if you say Y here.
  212. See also <file:Documentation/i386/IO-APIC.txt>,
  213. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  214. <http://www.tldp.org/docs.html#howto>.
  215. If you don't know what to do here, say N.
  216. config X86_X2APIC
  217. bool "Support x2apic"
  218. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  219. ---help---
  220. This enables x2apic support on CPUs that have this feature.
  221. This allows 32-bit apic IDs (so it can support very large systems),
  222. and accesses the local apic via MSRs not via mmio.
  223. If you don't know what to do here, say N.
  224. config X86_MPPARSE
  225. bool "Enable MPS table" if ACPI
  226. default y
  227. depends on X86_LOCAL_APIC
  228. ---help---
  229. For old smp systems that do not have proper acpi support. Newer systems
  230. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  231. config X86_BIGSMP
  232. bool "Support for big SMP systems with more than 8 CPUs"
  233. depends on X86_32 && SMP
  234. ---help---
  235. This option is needed for the systems that have more than 8 CPUs
  236. if X86_32
  237. config X86_EXTENDED_PLATFORM
  238. bool "Support for extended (non-PC) x86 platforms"
  239. default y
  240. ---help---
  241. If you disable this option then the kernel will only support
  242. standard PC platforms. (which covers the vast majority of
  243. systems out there.)
  244. If you enable this option then you'll be able to select support
  245. for the following (non-PC) 32 bit x86 platforms:
  246. AMD Elan
  247. NUMAQ (IBM/Sequent)
  248. RDC R-321x SoC
  249. SGI 320/540 (Visual Workstation)
  250. Summit/EXA (IBM x440)
  251. Unisys ES7000 IA32 series
  252. Moorestown MID devices
  253. If you have one of these systems, or if you want to build a
  254. generic distribution kernel, say Y here - otherwise say N.
  255. endif
  256. if X86_64
  257. config X86_EXTENDED_PLATFORM
  258. bool "Support for extended (non-PC) x86 platforms"
  259. default y
  260. ---help---
  261. If you disable this option then the kernel will only support
  262. standard PC platforms. (which covers the vast majority of
  263. systems out there.)
  264. If you enable this option then you'll be able to select support
  265. for the following (non-PC) 64 bit x86 platforms:
  266. ScaleMP vSMP
  267. SGI Ultraviolet
  268. If you have one of these systems, or if you want to build a
  269. generic distribution kernel, say Y here - otherwise say N.
  270. endif
  271. # This is an alphabetically sorted list of 64 bit extended platforms
  272. # Please maintain the alphabetic order if and when there are additions
  273. config X86_VSMP
  274. bool "ScaleMP vSMP"
  275. select PARAVIRT
  276. depends on X86_64 && PCI
  277. depends on X86_EXTENDED_PLATFORM
  278. ---help---
  279. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  280. supposed to run on these EM64T-based machines. Only choose this option
  281. if you have one of these machines.
  282. config X86_UV
  283. bool "SGI Ultraviolet"
  284. depends on X86_64
  285. depends on X86_EXTENDED_PLATFORM
  286. depends on NUMA
  287. depends on X86_X2APIC
  288. ---help---
  289. This option is needed in order to support SGI Ultraviolet systems.
  290. If you don't have one of these, you should say N here.
  291. # Following is an alphabetically sorted list of 32 bit extended platforms
  292. # Please maintain the alphabetic order if and when there are additions
  293. config X86_ELAN
  294. bool "AMD Elan"
  295. depends on X86_32
  296. depends on X86_EXTENDED_PLATFORM
  297. ---help---
  298. Select this for an AMD Elan processor.
  299. Do not use this option for K6/Athlon/Opteron processors!
  300. If unsure, choose "PC-compatible" instead.
  301. config X86_MRST
  302. bool "Moorestown MID platform"
  303. depends on PCI
  304. depends on PCI_GOANY
  305. depends on X86_32
  306. depends on X86_EXTENDED_PLATFORM
  307. depends on X86_IO_APIC
  308. select APB_TIMER
  309. ---help---
  310. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  311. Internet Device(MID) platform. Moorestown consists of two chips:
  312. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  313. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  314. nor standard legacy replacement devices/features. e.g. Moorestown does
  315. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  316. config X86_RDC321X
  317. bool "RDC R-321x SoC"
  318. depends on X86_32
  319. depends on X86_EXTENDED_PLATFORM
  320. select M486
  321. select X86_REBOOTFIXUPS
  322. ---help---
  323. This option is needed for RDC R-321x system-on-chip, also known
  324. as R-8610-(G).
  325. If you don't have one of these chips, you should say N here.
  326. config X86_32_NON_STANDARD
  327. bool "Support non-standard 32-bit SMP architectures"
  328. depends on X86_32 && SMP
  329. depends on X86_EXTENDED_PLATFORM
  330. ---help---
  331. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  332. subarchitectures. It is intended for a generic binary kernel.
  333. if you select them all, kernel will probe it one by one. and will
  334. fallback to default.
  335. # Alphabetically sorted list of Non standard 32 bit platforms
  336. config X86_NUMAQ
  337. bool "NUMAQ (IBM/Sequent)"
  338. depends on X86_32_NON_STANDARD
  339. depends on PCI
  340. select NUMA
  341. select X86_MPPARSE
  342. ---help---
  343. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  344. NUMA multiquad box. This changes the way that processors are
  345. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  346. of Flat Logical. You will need a new lynxer.elf file to flash your
  347. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  348. config X86_SUPPORTS_MEMORY_FAILURE
  349. def_bool y
  350. # MCE code calls memory_failure():
  351. depends on X86_MCE
  352. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  353. depends on !X86_NUMAQ
  354. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  355. depends on X86_64 || !SPARSEMEM
  356. select ARCH_SUPPORTS_MEMORY_FAILURE
  357. config X86_VISWS
  358. bool "SGI 320/540 (Visual Workstation)"
  359. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  360. depends on X86_32_NON_STANDARD
  361. ---help---
  362. The SGI Visual Workstation series is an IA32-based workstation
  363. based on SGI systems chips with some legacy PC hardware attached.
  364. Say Y here to create a kernel to run on the SGI 320 or 540.
  365. A kernel compiled for the Visual Workstation will run on general
  366. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  367. config X86_SUMMIT
  368. bool "Summit/EXA (IBM x440)"
  369. depends on X86_32_NON_STANDARD
  370. ---help---
  371. This option is needed for IBM systems that use the Summit/EXA chipset.
  372. In particular, it is needed for the x440.
  373. config X86_ES7000
  374. bool "Unisys ES7000 IA32 series"
  375. depends on X86_32_NON_STANDARD && X86_BIGSMP
  376. ---help---
  377. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  378. supposed to run on an IA32-based Unisys ES7000 system.
  379. config SCHED_OMIT_FRAME_POINTER
  380. def_bool y
  381. prompt "Single-depth WCHAN output"
  382. depends on X86
  383. ---help---
  384. Calculate simpler /proc/<PID>/wchan values. If this option
  385. is disabled then wchan values will recurse back to the
  386. caller function. This provides more accurate wchan values,
  387. at the expense of slightly more scheduling overhead.
  388. If in doubt, say "Y".
  389. menuconfig PARAVIRT_GUEST
  390. bool "Paravirtualized guest support"
  391. ---help---
  392. Say Y here to get to see options related to running Linux under
  393. various hypervisors. This option alone does not add any kernel code.
  394. If you say N, all options in this submenu will be skipped and disabled.
  395. if PARAVIRT_GUEST
  396. source "arch/x86/xen/Kconfig"
  397. config KVM_CLOCK
  398. bool "KVM paravirtualized clock"
  399. select PARAVIRT
  400. select PARAVIRT_CLOCK
  401. ---help---
  402. Turning on this option will allow you to run a paravirtualized clock
  403. when running over the KVM hypervisor. Instead of relying on a PIT
  404. (or probably other) emulation by the underlying device model, the host
  405. provides the guest with timing infrastructure such as time of day, and
  406. system time
  407. config KVM_GUEST
  408. bool "KVM Guest support"
  409. select PARAVIRT
  410. ---help---
  411. This option enables various optimizations for running under the KVM
  412. hypervisor.
  413. source "arch/x86/lguest/Kconfig"
  414. config PARAVIRT
  415. bool "Enable paravirtualization code"
  416. ---help---
  417. This changes the kernel so it can modify itself when it is run
  418. under a hypervisor, potentially improving performance significantly
  419. over full virtualization. However, when run without a hypervisor
  420. the kernel is theoretically slower and slightly larger.
  421. config PARAVIRT_SPINLOCKS
  422. bool "Paravirtualization layer for spinlocks"
  423. depends on PARAVIRT && SMP && EXPERIMENTAL
  424. ---help---
  425. Paravirtualized spinlocks allow a pvops backend to replace the
  426. spinlock implementation with something virtualization-friendly
  427. (for example, block the virtual CPU rather than spinning).
  428. Unfortunately the downside is an up to 5% performance hit on
  429. native kernels, with various workloads.
  430. If you are unsure how to answer this question, answer N.
  431. config PARAVIRT_CLOCK
  432. bool
  433. endif
  434. config PARAVIRT_DEBUG
  435. bool "paravirt-ops debugging"
  436. depends on PARAVIRT && DEBUG_KERNEL
  437. ---help---
  438. Enable to debug paravirt_ops internals. Specifically, BUG if
  439. a paravirt_op is missing when it is called.
  440. config NO_BOOTMEM
  441. default y
  442. bool "Disable Bootmem code"
  443. ---help---
  444. Use early_res directly instead of bootmem before slab is ready.
  445. - allocator (buddy) [generic]
  446. - early allocator (bootmem) [generic]
  447. - very early allocator (reserve_early*()) [x86]
  448. - very very early allocator (early brk model) [x86]
  449. So reduce one layer between early allocator to final allocator
  450. config MEMTEST
  451. bool "Memtest"
  452. ---help---
  453. This option adds a kernel parameter 'memtest', which allows memtest
  454. to be set.
  455. memtest=0, mean disabled; -- default
  456. memtest=1, mean do 1 test pattern;
  457. ...
  458. memtest=4, mean do 4 test patterns.
  459. If you are unsure how to answer this question, answer N.
  460. config X86_SUMMIT_NUMA
  461. def_bool y
  462. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  463. config X86_CYCLONE_TIMER
  464. def_bool y
  465. depends on X86_32_NON_STANDARD
  466. source "arch/x86/Kconfig.cpu"
  467. config HPET_TIMER
  468. def_bool X86_64
  469. prompt "HPET Timer Support" if X86_32
  470. ---help---
  471. Use the IA-PC HPET (High Precision Event Timer) to manage
  472. time in preference to the PIT and RTC, if a HPET is
  473. present.
  474. HPET is the next generation timer replacing legacy 8254s.
  475. The HPET provides a stable time base on SMP
  476. systems, unlike the TSC, but it is more expensive to access,
  477. as it is off-chip. You can find the HPET spec at
  478. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  479. You can safely choose Y here. However, HPET will only be
  480. activated if the platform and the BIOS support this feature.
  481. Otherwise the 8254 will be used for timing services.
  482. Choose N to continue using the legacy 8254 timer.
  483. config HPET_EMULATE_RTC
  484. def_bool y
  485. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  486. config APB_TIMER
  487. def_bool y if MRST
  488. prompt "Langwell APB Timer Support" if X86_MRST
  489. help
  490. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  491. The APBT provides a stable time base on SMP
  492. systems, unlike the TSC, but it is more expensive to access,
  493. as it is off-chip. APB timers are always running regardless of CPU
  494. C states, they are used as per CPU clockevent device when possible.
  495. # Mark as embedded because too many people got it wrong.
  496. # The code disables itself when not needed.
  497. config DMI
  498. default y
  499. bool "Enable DMI scanning" if EMBEDDED
  500. ---help---
  501. Enabled scanning of DMI to identify machine quirks. Say Y
  502. here unless you have verified that your setup is not
  503. affected by entries in the DMI blacklist. Required by PNP
  504. BIOS code.
  505. config GART_IOMMU
  506. bool "GART IOMMU support" if EMBEDDED
  507. default y
  508. select SWIOTLB
  509. depends on X86_64 && PCI && AMD_NB
  510. ---help---
  511. Support for full DMA access of devices with 32bit memory access only
  512. on systems with more than 3GB. This is usually needed for USB,
  513. sound, many IDE/SATA chipsets and some other devices.
  514. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  515. based hardware IOMMU and a software bounce buffer based IOMMU used
  516. on Intel systems and as fallback.
  517. The code is only active when needed (enough memory and limited
  518. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  519. too.
  520. config CALGARY_IOMMU
  521. bool "IBM Calgary IOMMU support"
  522. select SWIOTLB
  523. depends on X86_64 && PCI && EXPERIMENTAL
  524. ---help---
  525. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  526. systems. Needed to run systems with more than 3GB of memory
  527. properly with 32-bit PCI devices that do not support DAC
  528. (Double Address Cycle). Calgary also supports bus level
  529. isolation, where all DMAs pass through the IOMMU. This
  530. prevents them from going anywhere except their intended
  531. destination. This catches hard-to-find kernel bugs and
  532. mis-behaving drivers and devices that do not use the DMA-API
  533. properly to set up their DMA buffers. The IOMMU can be
  534. turned off at boot time with the iommu=off parameter.
  535. Normally the kernel will make the right choice by itself.
  536. If unsure, say Y.
  537. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  538. def_bool y
  539. prompt "Should Calgary be enabled by default?"
  540. depends on CALGARY_IOMMU
  541. ---help---
  542. Should Calgary be enabled by default? if you choose 'y', Calgary
  543. will be used (if it exists). If you choose 'n', Calgary will not be
  544. used even if it exists. If you choose 'n' and would like to use
  545. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  546. If unsure, say Y.
  547. config AMD_IOMMU
  548. bool "AMD IOMMU support"
  549. select SWIOTLB
  550. select PCI_MSI
  551. depends on X86_64 && PCI && ACPI
  552. ---help---
  553. With this option you can enable support for AMD IOMMU hardware in
  554. your system. An IOMMU is a hardware component which provides
  555. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  556. can isolate the the DMA memory of different devices and protect the
  557. system from misbehaving device drivers or hardware.
  558. You can find out if your system has an AMD IOMMU if you look into
  559. your BIOS for an option to enable it or if you have an IVRS ACPI
  560. table.
  561. config AMD_IOMMU_STATS
  562. bool "Export AMD IOMMU statistics to debugfs"
  563. depends on AMD_IOMMU
  564. select DEBUG_FS
  565. ---help---
  566. This option enables code in the AMD IOMMU driver to collect various
  567. statistics about whats happening in the driver and exports that
  568. information to userspace via debugfs.
  569. If unsure, say N.
  570. # need this always selected by IOMMU for the VIA workaround
  571. config SWIOTLB
  572. def_bool y if X86_64
  573. ---help---
  574. Support for software bounce buffers used on x86-64 systems
  575. which don't have a hardware IOMMU (e.g. the current generation
  576. of Intel's x86-64 CPUs). Using this PCI devices which can only
  577. access 32-bits of memory can be used on systems with more than
  578. 3 GB of memory. If unsure, say Y.
  579. config IOMMU_HELPER
  580. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  581. config IOMMU_API
  582. def_bool (AMD_IOMMU || DMAR)
  583. config MAXSMP
  584. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  585. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  586. select CPUMASK_OFFSTACK
  587. ---help---
  588. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  589. If unsure, say N.
  590. config NR_CPUS
  591. int "Maximum number of CPUs" if SMP && !MAXSMP
  592. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  593. range 2 512 if SMP && !MAXSMP
  594. default "1" if !SMP
  595. default "4096" if MAXSMP
  596. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  597. default "8" if SMP
  598. ---help---
  599. This allows you to specify the maximum number of CPUs which this
  600. kernel will support. The maximum supported value is 512 and the
  601. minimum value which makes sense is 2.
  602. This is purely to save memory - each supported CPU adds
  603. approximately eight kilobytes to the kernel image.
  604. config SCHED_SMT
  605. bool "SMT (Hyperthreading) scheduler support"
  606. depends on X86_HT
  607. ---help---
  608. SMT scheduler support improves the CPU scheduler's decision making
  609. when dealing with Intel Pentium 4 chips with HyperThreading at a
  610. cost of slightly increased overhead in some places. If unsure say
  611. N here.
  612. config SCHED_MC
  613. def_bool y
  614. prompt "Multi-core scheduler support"
  615. depends on X86_HT
  616. ---help---
  617. Multi-core scheduler support improves the CPU scheduler's decision
  618. making when dealing with multi-core CPU chips at a cost of slightly
  619. increased overhead in some places. If unsure say N here.
  620. config IRQ_TIME_ACCOUNTING
  621. bool "Fine granularity task level IRQ time accounting"
  622. default n
  623. ---help---
  624. Select this option to enable fine granularity task irq time
  625. accounting. This is done by reading a timestamp on each
  626. transitions between softirq and hardirq state, so there can be a
  627. small performance impact.
  628. If in doubt, say N here.
  629. source "kernel/Kconfig.preempt"
  630. config X86_UP_APIC
  631. bool "Local APIC support on uniprocessors"
  632. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  633. ---help---
  634. A local APIC (Advanced Programmable Interrupt Controller) is an
  635. integrated interrupt controller in the CPU. If you have a single-CPU
  636. system which has a processor with a local APIC, you can say Y here to
  637. enable and use it. If you say Y here even though your machine doesn't
  638. have a local APIC, then the kernel will still run with no slowdown at
  639. all. The local APIC supports CPU-generated self-interrupts (timer,
  640. performance counters), and the NMI watchdog which detects hard
  641. lockups.
  642. config X86_UP_IOAPIC
  643. bool "IO-APIC support on uniprocessors"
  644. depends on X86_UP_APIC
  645. ---help---
  646. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  647. SMP-capable replacement for PC-style interrupt controllers. Most
  648. SMP systems and many recent uniprocessor systems have one.
  649. If you have a single-CPU system with an IO-APIC, you can say Y here
  650. to use it. If you say Y here even though your machine doesn't have
  651. an IO-APIC, then the kernel will still run with no slowdown at all.
  652. config X86_LOCAL_APIC
  653. def_bool y
  654. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  655. config X86_IO_APIC
  656. def_bool y
  657. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  658. config X86_VISWS_APIC
  659. def_bool y
  660. depends on X86_32 && X86_VISWS
  661. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  662. bool "Reroute for broken boot IRQs"
  663. depends on X86_IO_APIC
  664. ---help---
  665. This option enables a workaround that fixes a source of
  666. spurious interrupts. This is recommended when threaded
  667. interrupt handling is used on systems where the generation of
  668. superfluous "boot interrupts" cannot be disabled.
  669. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  670. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  671. kernel does during interrupt handling). On chipsets where this
  672. boot IRQ generation cannot be disabled, this workaround keeps
  673. the original IRQ line masked so that only the equivalent "boot
  674. IRQ" is delivered to the CPUs. The workaround also tells the
  675. kernel to set up the IRQ handler on the boot IRQ line. In this
  676. way only one interrupt is delivered to the kernel. Otherwise
  677. the spurious second interrupt may cause the kernel to bring
  678. down (vital) interrupt lines.
  679. Only affects "broken" chipsets. Interrupt sharing may be
  680. increased on these systems.
  681. config X86_MCE
  682. bool "Machine Check / overheating reporting"
  683. ---help---
  684. Machine Check support allows the processor to notify the
  685. kernel if it detects a problem (e.g. overheating, data corruption).
  686. The action the kernel takes depends on the severity of the problem,
  687. ranging from warning messages to halting the machine.
  688. config X86_MCE_INTEL
  689. def_bool y
  690. prompt "Intel MCE features"
  691. depends on X86_MCE && X86_LOCAL_APIC
  692. ---help---
  693. Additional support for intel specific MCE features such as
  694. the thermal monitor.
  695. config X86_MCE_AMD
  696. def_bool y
  697. prompt "AMD MCE features"
  698. depends on X86_MCE && X86_LOCAL_APIC
  699. ---help---
  700. Additional support for AMD specific MCE features such as
  701. the DRAM Error Threshold.
  702. config X86_ANCIENT_MCE
  703. bool "Support for old Pentium 5 / WinChip machine checks"
  704. depends on X86_32 && X86_MCE
  705. ---help---
  706. Include support for machine check handling on old Pentium 5 or WinChip
  707. systems. These typically need to be enabled explicitely on the command
  708. line.
  709. config X86_MCE_THRESHOLD
  710. depends on X86_MCE_AMD || X86_MCE_INTEL
  711. def_bool y
  712. config X86_MCE_INJECT
  713. depends on X86_MCE
  714. tristate "Machine check injector support"
  715. ---help---
  716. Provide support for injecting machine checks for testing purposes.
  717. If you don't know what a machine check is and you don't do kernel
  718. QA it is safe to say n.
  719. config X86_THERMAL_VECTOR
  720. def_bool y
  721. depends on X86_MCE_INTEL
  722. config VM86
  723. bool "Enable VM86 support" if EMBEDDED
  724. default y
  725. depends on X86_32
  726. ---help---
  727. This option is required by programs like DOSEMU to run 16-bit legacy
  728. code on X86 processors. It also may be needed by software like
  729. XFree86 to initialize some video cards via BIOS. Disabling this
  730. option saves about 6k.
  731. config TOSHIBA
  732. tristate "Toshiba Laptop support"
  733. depends on X86_32
  734. ---help---
  735. This adds a driver to safely access the System Management Mode of
  736. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  737. not work on models with a Phoenix BIOS. The System Management Mode
  738. is used to set the BIOS and power saving options on Toshiba portables.
  739. For information on utilities to make use of this driver see the
  740. Toshiba Linux utilities web site at:
  741. <http://www.buzzard.org.uk/toshiba/>.
  742. Say Y if you intend to run this kernel on a Toshiba portable.
  743. Say N otherwise.
  744. config I8K
  745. tristate "Dell laptop support"
  746. ---help---
  747. This adds a driver to safely access the System Management Mode
  748. of the CPU on the Dell Inspiron 8000. The System Management Mode
  749. is used to read cpu temperature and cooling fan status and to
  750. control the fans on the I8K portables.
  751. This driver has been tested only on the Inspiron 8000 but it may
  752. also work with other Dell laptops. You can force loading on other
  753. models by passing the parameter `force=1' to the module. Use at
  754. your own risk.
  755. For information on utilities to make use of this driver see the
  756. I8K Linux utilities web site at:
  757. <http://people.debian.org/~dz/i8k/>
  758. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  759. Say N otherwise.
  760. config X86_REBOOTFIXUPS
  761. bool "Enable X86 board specific fixups for reboot"
  762. depends on X86_32
  763. ---help---
  764. This enables chipset and/or board specific fixups to be done
  765. in order to get reboot to work correctly. This is only needed on
  766. some combinations of hardware and BIOS. The symptom, for which
  767. this config is intended, is when reboot ends with a stalled/hung
  768. system.
  769. Currently, the only fixup is for the Geode machines using
  770. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  771. Say Y if you want to enable the fixup. Currently, it's safe to
  772. enable this option even if you don't need it.
  773. Say N otherwise.
  774. config MICROCODE
  775. tristate "/dev/cpu/microcode - microcode support"
  776. select FW_LOADER
  777. ---help---
  778. If you say Y here, you will be able to update the microcode on
  779. certain Intel and AMD processors. The Intel support is for the
  780. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  781. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  782. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  783. You will obviously need the actual microcode binary data itself
  784. which is not shipped with the Linux kernel.
  785. This option selects the general module only, you need to select
  786. at least one vendor specific module as well.
  787. To compile this driver as a module, choose M here: the
  788. module will be called microcode.
  789. config MICROCODE_INTEL
  790. bool "Intel microcode patch loading support"
  791. depends on MICROCODE
  792. default MICROCODE
  793. select FW_LOADER
  794. ---help---
  795. This options enables microcode patch loading support for Intel
  796. processors.
  797. For latest news and information on obtaining all the required
  798. Intel ingredients for this driver, check:
  799. <http://www.urbanmyth.org/microcode/>.
  800. config MICROCODE_AMD
  801. bool "AMD microcode patch loading support"
  802. depends on MICROCODE
  803. select FW_LOADER
  804. ---help---
  805. If you select this option, microcode patch loading support for AMD
  806. processors will be enabled.
  807. config MICROCODE_OLD_INTERFACE
  808. def_bool y
  809. depends on MICROCODE
  810. config X86_MSR
  811. tristate "/dev/cpu/*/msr - Model-specific register support"
  812. ---help---
  813. This device gives privileged processes access to the x86
  814. Model-Specific Registers (MSRs). It is a character device with
  815. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  816. MSR accesses are directed to a specific CPU on multi-processor
  817. systems.
  818. config X86_CPUID
  819. tristate "/dev/cpu/*/cpuid - CPU information support"
  820. ---help---
  821. This device gives processes access to the x86 CPUID instruction to
  822. be executed on a specific processor. It is a character device
  823. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  824. /dev/cpu/31/cpuid.
  825. choice
  826. prompt "High Memory Support"
  827. default HIGHMEM64G if X86_NUMAQ
  828. default HIGHMEM4G
  829. depends on X86_32
  830. config NOHIGHMEM
  831. bool "off"
  832. depends on !X86_NUMAQ
  833. ---help---
  834. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  835. However, the address space of 32-bit x86 processors is only 4
  836. Gigabytes large. That means that, if you have a large amount of
  837. physical memory, not all of it can be "permanently mapped" by the
  838. kernel. The physical memory that's not permanently mapped is called
  839. "high memory".
  840. If you are compiling a kernel which will never run on a machine with
  841. more than 1 Gigabyte total physical RAM, answer "off" here (default
  842. choice and suitable for most users). This will result in a "3GB/1GB"
  843. split: 3GB are mapped so that each process sees a 3GB virtual memory
  844. space and the remaining part of the 4GB virtual memory space is used
  845. by the kernel to permanently map as much physical memory as
  846. possible.
  847. If the machine has between 1 and 4 Gigabytes physical RAM, then
  848. answer "4GB" here.
  849. If more than 4 Gigabytes is used then answer "64GB" here. This
  850. selection turns Intel PAE (Physical Address Extension) mode on.
  851. PAE implements 3-level paging on IA32 processors. PAE is fully
  852. supported by Linux, PAE mode is implemented on all recent Intel
  853. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  854. then the kernel will not boot on CPUs that don't support PAE!
  855. The actual amount of total physical memory will either be
  856. auto detected or can be forced by using a kernel command line option
  857. such as "mem=256M". (Try "man bootparam" or see the documentation of
  858. your boot loader (lilo or loadlin) about how to pass options to the
  859. kernel at boot time.)
  860. If unsure, say "off".
  861. config HIGHMEM4G
  862. bool "4GB"
  863. depends on !X86_NUMAQ
  864. ---help---
  865. Select this if you have a 32-bit processor and between 1 and 4
  866. gigabytes of physical RAM.
  867. config HIGHMEM64G
  868. bool "64GB"
  869. depends on !M386 && !M486
  870. select X86_PAE
  871. ---help---
  872. Select this if you have a 32-bit processor and more than 4
  873. gigabytes of physical RAM.
  874. endchoice
  875. choice
  876. depends on EXPERIMENTAL
  877. prompt "Memory split" if EMBEDDED
  878. default VMSPLIT_3G
  879. depends on X86_32
  880. ---help---
  881. Select the desired split between kernel and user memory.
  882. If the address range available to the kernel is less than the
  883. physical memory installed, the remaining memory will be available
  884. as "high memory". Accessing high memory is a little more costly
  885. than low memory, as it needs to be mapped into the kernel first.
  886. Note that increasing the kernel address space limits the range
  887. available to user programs, making the address space there
  888. tighter. Selecting anything other than the default 3G/1G split
  889. will also likely make your kernel incompatible with binary-only
  890. kernel modules.
  891. If you are not absolutely sure what you are doing, leave this
  892. option alone!
  893. config VMSPLIT_3G
  894. bool "3G/1G user/kernel split"
  895. config VMSPLIT_3G_OPT
  896. depends on !X86_PAE
  897. bool "3G/1G user/kernel split (for full 1G low memory)"
  898. config VMSPLIT_2G
  899. bool "2G/2G user/kernel split"
  900. config VMSPLIT_2G_OPT
  901. depends on !X86_PAE
  902. bool "2G/2G user/kernel split (for full 2G low memory)"
  903. config VMSPLIT_1G
  904. bool "1G/3G user/kernel split"
  905. endchoice
  906. config PAGE_OFFSET
  907. hex
  908. default 0xB0000000 if VMSPLIT_3G_OPT
  909. default 0x80000000 if VMSPLIT_2G
  910. default 0x78000000 if VMSPLIT_2G_OPT
  911. default 0x40000000 if VMSPLIT_1G
  912. default 0xC0000000
  913. depends on X86_32
  914. config HIGHMEM
  915. def_bool y
  916. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  917. config X86_PAE
  918. bool "PAE (Physical Address Extension) Support"
  919. depends on X86_32 && !HIGHMEM4G
  920. ---help---
  921. PAE is required for NX support, and furthermore enables
  922. larger swapspace support for non-overcommit purposes. It
  923. has the cost of more pagetable lookup overhead, and also
  924. consumes more pagetable space per process.
  925. config ARCH_PHYS_ADDR_T_64BIT
  926. def_bool X86_64 || X86_PAE
  927. config ARCH_DMA_ADDR_T_64BIT
  928. def_bool X86_64 || HIGHMEM64G
  929. config DIRECT_GBPAGES
  930. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  931. default y
  932. depends on X86_64
  933. ---help---
  934. Allow the kernel linear mapping to use 1GB pages on CPUs that
  935. support it. This can improve the kernel's performance a tiny bit by
  936. reducing TLB pressure. If in doubt, say "Y".
  937. # Common NUMA Features
  938. config NUMA
  939. bool "Numa Memory Allocation and Scheduler Support"
  940. depends on SMP
  941. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  942. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  943. ---help---
  944. Enable NUMA (Non Uniform Memory Access) support.
  945. The kernel will try to allocate memory used by a CPU on the
  946. local memory controller of the CPU and add some more
  947. NUMA awareness to the kernel.
  948. For 64-bit this is recommended if the system is Intel Core i7
  949. (or later), AMD Opteron, or EM64T NUMA.
  950. For 32-bit this is only needed on (rare) 32-bit-only platforms
  951. that support NUMA topologies, such as NUMAQ / Summit, or if you
  952. boot a 32-bit kernel on a 64-bit NUMA platform.
  953. Otherwise, you should say N.
  954. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  955. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  956. config K8_NUMA
  957. def_bool y
  958. prompt "Old style AMD Opteron NUMA detection"
  959. depends on X86_64 && NUMA && PCI
  960. ---help---
  961. Enable K8 NUMA node topology detection. You should say Y here if
  962. you have a multi processor AMD K8 system. This uses an old
  963. method to read the NUMA configuration directly from the builtin
  964. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  965. instead, which also takes priority if both are compiled in.
  966. config X86_64_ACPI_NUMA
  967. def_bool y
  968. prompt "ACPI NUMA detection"
  969. depends on X86_64 && NUMA && ACPI && PCI
  970. select ACPI_NUMA
  971. ---help---
  972. Enable ACPI SRAT based node topology detection.
  973. # Some NUMA nodes have memory ranges that span
  974. # other nodes. Even though a pfn is valid and
  975. # between a node's start and end pfns, it may not
  976. # reside on that node. See memmap_init_zone()
  977. # for details.
  978. config NODES_SPAN_OTHER_NODES
  979. def_bool y
  980. depends on X86_64_ACPI_NUMA
  981. config NUMA_EMU
  982. bool "NUMA emulation"
  983. depends on X86_64 && NUMA
  984. ---help---
  985. Enable NUMA emulation. A flat machine will be split
  986. into virtual nodes when booted with "numa=fake=N", where N is the
  987. number of nodes. This is only useful for debugging.
  988. config NODES_SHIFT
  989. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  990. range 1 10
  991. default "10" if MAXSMP
  992. default "6" if X86_64
  993. default "4" if X86_NUMAQ
  994. default "3"
  995. depends on NEED_MULTIPLE_NODES
  996. ---help---
  997. Specify the maximum number of NUMA Nodes available on the target
  998. system. Increases memory reserved to accommodate various tables.
  999. config HAVE_ARCH_BOOTMEM
  1000. def_bool y
  1001. depends on X86_32 && NUMA
  1002. config ARCH_HAVE_MEMORY_PRESENT
  1003. def_bool y
  1004. depends on X86_32 && DISCONTIGMEM
  1005. config NEED_NODE_MEMMAP_SIZE
  1006. def_bool y
  1007. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1008. config HAVE_ARCH_ALLOC_REMAP
  1009. def_bool y
  1010. depends on X86_32 && NUMA
  1011. config ARCH_FLATMEM_ENABLE
  1012. def_bool y
  1013. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1014. config ARCH_DISCONTIGMEM_ENABLE
  1015. def_bool y
  1016. depends on NUMA && X86_32
  1017. config ARCH_DISCONTIGMEM_DEFAULT
  1018. def_bool y
  1019. depends on NUMA && X86_32
  1020. config ARCH_PROC_KCORE_TEXT
  1021. def_bool y
  1022. depends on X86_64 && PROC_KCORE
  1023. config ARCH_SPARSEMEM_DEFAULT
  1024. def_bool y
  1025. depends on X86_64
  1026. config ARCH_SPARSEMEM_ENABLE
  1027. def_bool y
  1028. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1029. select SPARSEMEM_STATIC if X86_32
  1030. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1031. config ARCH_SELECT_MEMORY_MODEL
  1032. def_bool y
  1033. depends on ARCH_SPARSEMEM_ENABLE
  1034. config ARCH_MEMORY_PROBE
  1035. def_bool X86_64
  1036. depends on MEMORY_HOTPLUG
  1037. config ILLEGAL_POINTER_VALUE
  1038. hex
  1039. default 0 if X86_32
  1040. default 0xdead000000000000 if X86_64
  1041. source "mm/Kconfig"
  1042. config HIGHPTE
  1043. bool "Allocate 3rd-level pagetables from highmem"
  1044. depends on HIGHMEM
  1045. ---help---
  1046. The VM uses one page table entry for each page of physical memory.
  1047. For systems with a lot of RAM, this can be wasteful of precious
  1048. low memory. Setting this option will put user-space page table
  1049. entries in high memory.
  1050. config X86_CHECK_BIOS_CORRUPTION
  1051. bool "Check for low memory corruption"
  1052. ---help---
  1053. Periodically check for memory corruption in low memory, which
  1054. is suspected to be caused by BIOS. Even when enabled in the
  1055. configuration, it is disabled at runtime. Enable it by
  1056. setting "memory_corruption_check=1" on the kernel command
  1057. line. By default it scans the low 64k of memory every 60
  1058. seconds; see the memory_corruption_check_size and
  1059. memory_corruption_check_period parameters in
  1060. Documentation/kernel-parameters.txt to adjust this.
  1061. When enabled with the default parameters, this option has
  1062. almost no overhead, as it reserves a relatively small amount
  1063. of memory and scans it infrequently. It both detects corruption
  1064. and prevents it from affecting the running system.
  1065. It is, however, intended as a diagnostic tool; if repeatable
  1066. BIOS-originated corruption always affects the same memory,
  1067. you can use memmap= to prevent the kernel from using that
  1068. memory.
  1069. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1070. bool "Set the default setting of memory_corruption_check"
  1071. depends on X86_CHECK_BIOS_CORRUPTION
  1072. default y
  1073. ---help---
  1074. Set whether the default state of memory_corruption_check is
  1075. on or off.
  1076. config X86_RESERVE_LOW
  1077. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1078. default 64
  1079. range 4 640
  1080. ---help---
  1081. Specify the amount of low memory to reserve for the BIOS.
  1082. The first page contains BIOS data structures that the kernel
  1083. must not use, so that page must always be reserved.
  1084. By default we reserve the first 64K of physical RAM, as a
  1085. number of BIOSes are known to corrupt that memory range
  1086. during events such as suspend/resume or monitor cable
  1087. insertion, so it must not be used by the kernel.
  1088. You can set this to 4 if you are absolutely sure that you
  1089. trust the BIOS to get all its memory reservations and usages
  1090. right. If you know your BIOS have problems beyond the
  1091. default 64K area, you can set this to 640 to avoid using the
  1092. entire low memory range.
  1093. If you have doubts about the BIOS (e.g. suspend/resume does
  1094. not work or there's kernel crashes after certain hardware
  1095. hotplug events) then you might want to enable
  1096. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1097. typical corruption patterns.
  1098. Leave this to the default value of 64 if you are unsure.
  1099. config MATH_EMULATION
  1100. bool
  1101. prompt "Math emulation" if X86_32
  1102. ---help---
  1103. Linux can emulate a math coprocessor (used for floating point
  1104. operations) if you don't have one. 486DX and Pentium processors have
  1105. a math coprocessor built in, 486SX and 386 do not, unless you added
  1106. a 487DX or 387, respectively. (The messages during boot time can
  1107. give you some hints here ["man dmesg"].) Everyone needs either a
  1108. coprocessor or this emulation.
  1109. If you don't have a math coprocessor, you need to say Y here; if you
  1110. say Y here even though you have a coprocessor, the coprocessor will
  1111. be used nevertheless. (This behavior can be changed with the kernel
  1112. command line option "no387", which comes handy if your coprocessor
  1113. is broken. Try "man bootparam" or see the documentation of your boot
  1114. loader (lilo or loadlin) about how to pass options to the kernel at
  1115. boot time.) This means that it is a good idea to say Y here if you
  1116. intend to use this kernel on different machines.
  1117. More information about the internals of the Linux math coprocessor
  1118. emulation can be found in <file:arch/x86/math-emu/README>.
  1119. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1120. kernel, it won't hurt.
  1121. config MTRR
  1122. def_bool y
  1123. prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
  1124. ---help---
  1125. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1126. the Memory Type Range Registers (MTRRs) may be used to control
  1127. processor access to memory ranges. This is most useful if you have
  1128. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1129. allows bus write transfers to be combined into a larger transfer
  1130. before bursting over the PCI/AGP bus. This can increase performance
  1131. of image write operations 2.5 times or more. Saying Y here creates a
  1132. /proc/mtrr file which may be used to manipulate your processor's
  1133. MTRRs. Typically the X server should use this.
  1134. This code has a reasonably generic interface so that similar
  1135. control registers on other processors can be easily supported
  1136. as well:
  1137. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1138. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1139. these, the ARRs are used to emulate the MTRRs.
  1140. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1141. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1142. write-combining. All of these processors are supported by this code
  1143. and it makes sense to say Y here if you have one of them.
  1144. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1145. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1146. can lead to all sorts of problems, so it's good to say Y here.
  1147. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1148. just add about 9 KB to your kernel.
  1149. See <file:Documentation/x86/mtrr.txt> for more information.
  1150. config MTRR_SANITIZER
  1151. def_bool y
  1152. prompt "MTRR cleanup support"
  1153. depends on MTRR
  1154. ---help---
  1155. Convert MTRR layout from continuous to discrete, so X drivers can
  1156. add writeback entries.
  1157. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1158. The largest mtrr entry size for a continuous block can be set with
  1159. mtrr_chunk_size.
  1160. If unsure, say Y.
  1161. config MTRR_SANITIZER_ENABLE_DEFAULT
  1162. int "MTRR cleanup enable value (0-1)"
  1163. range 0 1
  1164. default "0"
  1165. depends on MTRR_SANITIZER
  1166. ---help---
  1167. Enable mtrr cleanup default value
  1168. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1169. int "MTRR cleanup spare reg num (0-7)"
  1170. range 0 7
  1171. default "1"
  1172. depends on MTRR_SANITIZER
  1173. ---help---
  1174. mtrr cleanup spare entries default, it can be changed via
  1175. mtrr_spare_reg_nr=N on the kernel command line.
  1176. config X86_PAT
  1177. def_bool y
  1178. prompt "x86 PAT support" if EMBEDDED
  1179. depends on MTRR
  1180. ---help---
  1181. Use PAT attributes to setup page level cache control.
  1182. PATs are the modern equivalents of MTRRs and are much more
  1183. flexible than MTRRs.
  1184. Say N here if you see bootup problems (boot crash, boot hang,
  1185. spontaneous reboots) or a non-working video driver.
  1186. If unsure, say Y.
  1187. config ARCH_USES_PG_UNCACHED
  1188. def_bool y
  1189. depends on X86_PAT
  1190. config EFI
  1191. bool "EFI runtime service support"
  1192. depends on ACPI
  1193. ---help---
  1194. This enables the kernel to use EFI runtime services that are
  1195. available (such as the EFI variable services).
  1196. This option is only useful on systems that have EFI firmware.
  1197. In addition, you should use the latest ELILO loader available
  1198. at <http://elilo.sourceforge.net> in order to take advantage
  1199. of EFI runtime services. However, even with this option, the
  1200. resultant kernel should continue to boot on existing non-EFI
  1201. platforms.
  1202. config SECCOMP
  1203. def_bool y
  1204. prompt "Enable seccomp to safely compute untrusted bytecode"
  1205. ---help---
  1206. This kernel feature is useful for number crunching applications
  1207. that may need to compute untrusted bytecode during their
  1208. execution. By using pipes or other transports made available to
  1209. the process as file descriptors supporting the read/write
  1210. syscalls, it's possible to isolate those applications in
  1211. their own address space using seccomp. Once seccomp is
  1212. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1213. and the task is only allowed to execute a few safe syscalls
  1214. defined by each seccomp mode.
  1215. If unsure, say Y. Only embedded should say N here.
  1216. config CC_STACKPROTECTOR
  1217. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1218. ---help---
  1219. This option turns on the -fstack-protector GCC feature. This
  1220. feature puts, at the beginning of functions, a canary value on
  1221. the stack just before the return address, and validates
  1222. the value just before actually returning. Stack based buffer
  1223. overflows (that need to overwrite this return address) now also
  1224. overwrite the canary, which gets detected and the attack is then
  1225. neutralized via a kernel panic.
  1226. This feature requires gcc version 4.2 or above, or a distribution
  1227. gcc with the feature backported. Older versions are automatically
  1228. detected and for those versions, this configuration option is
  1229. ignored. (and a warning is printed during bootup)
  1230. source kernel/Kconfig.hz
  1231. config KEXEC
  1232. bool "kexec system call"
  1233. ---help---
  1234. kexec is a system call that implements the ability to shutdown your
  1235. current kernel, and to start another kernel. It is like a reboot
  1236. but it is independent of the system firmware. And like a reboot
  1237. you can start any kernel with it, not just Linux.
  1238. The name comes from the similarity to the exec system call.
  1239. It is an ongoing process to be certain the hardware in a machine
  1240. is properly shutdown, so do not be surprised if this code does not
  1241. initially work for you. It may help to enable device hotplugging
  1242. support. As of this writing the exact hardware interface is
  1243. strongly in flux, so no good recommendation can be made.
  1244. config CRASH_DUMP
  1245. bool "kernel crash dumps"
  1246. depends on X86_64 || (X86_32 && HIGHMEM)
  1247. ---help---
  1248. Generate crash dump after being started by kexec.
  1249. This should be normally only set in special crash dump kernels
  1250. which are loaded in the main kernel with kexec-tools into
  1251. a specially reserved region and then later executed after
  1252. a crash by kdump/kexec. The crash dump kernel must be compiled
  1253. to a memory address not used by the main kernel or BIOS using
  1254. PHYSICAL_START, or it must be built as a relocatable image
  1255. (CONFIG_RELOCATABLE=y).
  1256. For more details see Documentation/kdump/kdump.txt
  1257. config KEXEC_JUMP
  1258. bool "kexec jump (EXPERIMENTAL)"
  1259. depends on EXPERIMENTAL
  1260. depends on KEXEC && HIBERNATION
  1261. ---help---
  1262. Jump between original kernel and kexeced kernel and invoke
  1263. code in physical address mode via KEXEC
  1264. config PHYSICAL_START
  1265. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1266. default "0x1000000"
  1267. ---help---
  1268. This gives the physical address where the kernel is loaded.
  1269. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1270. bzImage will decompress itself to above physical address and
  1271. run from there. Otherwise, bzImage will run from the address where
  1272. it has been loaded by the boot loader and will ignore above physical
  1273. address.
  1274. In normal kdump cases one does not have to set/change this option
  1275. as now bzImage can be compiled as a completely relocatable image
  1276. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1277. address. This option is mainly useful for the folks who don't want
  1278. to use a bzImage for capturing the crash dump and want to use a
  1279. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1280. to be specifically compiled to run from a specific memory area
  1281. (normally a reserved region) and this option comes handy.
  1282. So if you are using bzImage for capturing the crash dump,
  1283. leave the value here unchanged to 0x1000000 and set
  1284. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1285. for capturing the crash dump change this value to start of
  1286. the reserved region. In other words, it can be set based on
  1287. the "X" value as specified in the "crashkernel=YM@XM"
  1288. command line boot parameter passed to the panic-ed
  1289. kernel. Please take a look at Documentation/kdump/kdump.txt
  1290. for more details about crash dumps.
  1291. Usage of bzImage for capturing the crash dump is recommended as
  1292. one does not have to build two kernels. Same kernel can be used
  1293. as production kernel and capture kernel. Above option should have
  1294. gone away after relocatable bzImage support is introduced. But it
  1295. is present because there are users out there who continue to use
  1296. vmlinux for dump capture. This option should go away down the
  1297. line.
  1298. Don't change this unless you know what you are doing.
  1299. config RELOCATABLE
  1300. bool "Build a relocatable kernel"
  1301. default y
  1302. ---help---
  1303. This builds a kernel image that retains relocation information
  1304. so it can be loaded someplace besides the default 1MB.
  1305. The relocations tend to make the kernel binary about 10% larger,
  1306. but are discarded at runtime.
  1307. One use is for the kexec on panic case where the recovery kernel
  1308. must live at a different physical address than the primary
  1309. kernel.
  1310. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1311. it has been loaded at and the compile time physical address
  1312. (CONFIG_PHYSICAL_START) is ignored.
  1313. # Relocation on x86-32 needs some additional build support
  1314. config X86_NEED_RELOCS
  1315. def_bool y
  1316. depends on X86_32 && RELOCATABLE
  1317. config PHYSICAL_ALIGN
  1318. hex "Alignment value to which kernel should be aligned" if X86_32
  1319. default "0x1000000"
  1320. range 0x2000 0x1000000
  1321. ---help---
  1322. This value puts the alignment restrictions on physical address
  1323. where kernel is loaded and run from. Kernel is compiled for an
  1324. address which meets above alignment restriction.
  1325. If bootloader loads the kernel at a non-aligned address and
  1326. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1327. address aligned to above value and run from there.
  1328. If bootloader loads the kernel at a non-aligned address and
  1329. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1330. load address and decompress itself to the address it has been
  1331. compiled for and run from there. The address for which kernel is
  1332. compiled already meets above alignment restrictions. Hence the
  1333. end result is that kernel runs from a physical address meeting
  1334. above alignment restrictions.
  1335. Don't change this unless you know what you are doing.
  1336. config HOTPLUG_CPU
  1337. bool "Support for hot-pluggable CPUs"
  1338. depends on SMP && HOTPLUG
  1339. ---help---
  1340. Say Y here to allow turning CPUs off and on. CPUs can be
  1341. controlled through /sys/devices/system/cpu.
  1342. ( Note: power management support will enable this option
  1343. automatically on SMP systems. )
  1344. Say N if you want to disable CPU hotplug.
  1345. config COMPAT_VDSO
  1346. def_bool y
  1347. prompt "Compat VDSO support"
  1348. depends on X86_32 || IA32_EMULATION
  1349. ---help---
  1350. Map the 32-bit VDSO to the predictable old-style address too.
  1351. Say N here if you are running a sufficiently recent glibc
  1352. version (2.3.3 or later), to remove the high-mapped
  1353. VDSO mapping and to exclusively use the randomized VDSO.
  1354. If unsure, say Y.
  1355. config CMDLINE_BOOL
  1356. bool "Built-in kernel command line"
  1357. ---help---
  1358. Allow for specifying boot arguments to the kernel at
  1359. build time. On some systems (e.g. embedded ones), it is
  1360. necessary or convenient to provide some or all of the
  1361. kernel boot arguments with the kernel itself (that is,
  1362. to not rely on the boot loader to provide them.)
  1363. To compile command line arguments into the kernel,
  1364. set this option to 'Y', then fill in the
  1365. the boot arguments in CONFIG_CMDLINE.
  1366. Systems with fully functional boot loaders (i.e. non-embedded)
  1367. should leave this option set to 'N'.
  1368. config CMDLINE
  1369. string "Built-in kernel command string"
  1370. depends on CMDLINE_BOOL
  1371. default ""
  1372. ---help---
  1373. Enter arguments here that should be compiled into the kernel
  1374. image and used at boot time. If the boot loader provides a
  1375. command line at boot time, it is appended to this string to
  1376. form the full kernel command line, when the system boots.
  1377. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1378. change this behavior.
  1379. In most cases, the command line (whether built-in or provided
  1380. by the boot loader) should specify the device for the root
  1381. file system.
  1382. config CMDLINE_OVERRIDE
  1383. bool "Built-in command line overrides boot loader arguments"
  1384. depends on CMDLINE_BOOL
  1385. ---help---
  1386. Set this option to 'Y' to have the kernel ignore the boot loader
  1387. command line, and use ONLY the built-in command line.
  1388. This is used to work around broken boot loaders. This should
  1389. be set to 'N' under normal conditions.
  1390. endmenu
  1391. config ARCH_ENABLE_MEMORY_HOTPLUG
  1392. def_bool y
  1393. depends on X86_64 || (X86_32 && HIGHMEM)
  1394. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1395. def_bool y
  1396. depends on MEMORY_HOTPLUG
  1397. config HAVE_ARCH_EARLY_PFN_TO_NID
  1398. def_bool X86_64
  1399. depends on NUMA
  1400. config USE_PERCPU_NUMA_NODE_ID
  1401. def_bool X86_64
  1402. depends on NUMA
  1403. menu "Power management and ACPI options"
  1404. config ARCH_HIBERNATION_HEADER
  1405. def_bool y
  1406. depends on X86_64 && HIBERNATION
  1407. source "kernel/power/Kconfig"
  1408. source "drivers/acpi/Kconfig"
  1409. source "drivers/sfi/Kconfig"
  1410. config X86_APM_BOOT
  1411. def_bool y
  1412. depends on APM || APM_MODULE
  1413. menuconfig APM
  1414. tristate "APM (Advanced Power Management) BIOS support"
  1415. depends on X86_32 && PM_SLEEP
  1416. ---help---
  1417. APM is a BIOS specification for saving power using several different
  1418. techniques. This is mostly useful for battery powered laptops with
  1419. APM compliant BIOSes. If you say Y here, the system time will be
  1420. reset after a RESUME operation, the /proc/apm device will provide
  1421. battery status information, and user-space programs will receive
  1422. notification of APM "events" (e.g. battery status change).
  1423. If you select "Y" here, you can disable actual use of the APM
  1424. BIOS by passing the "apm=off" option to the kernel at boot time.
  1425. Note that the APM support is almost completely disabled for
  1426. machines with more than one CPU.
  1427. In order to use APM, you will need supporting software. For location
  1428. and more information, read <file:Documentation/power/pm.txt> and the
  1429. Battery Powered Linux mini-HOWTO, available from
  1430. <http://www.tldp.org/docs.html#howto>.
  1431. This driver does not spin down disk drives (see the hdparm(8)
  1432. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1433. VESA-compliant "green" monitors.
  1434. This driver does not support the TI 4000M TravelMate and the ACER
  1435. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1436. desktop machines also don't have compliant BIOSes, and this driver
  1437. may cause those machines to panic during the boot phase.
  1438. Generally, if you don't have a battery in your machine, there isn't
  1439. much point in using this driver and you should say N. If you get
  1440. random kernel OOPSes or reboots that don't seem to be related to
  1441. anything, try disabling/enabling this option (or disabling/enabling
  1442. APM in your BIOS).
  1443. Some other things you should try when experiencing seemingly random,
  1444. "weird" problems:
  1445. 1) make sure that you have enough swap space and that it is
  1446. enabled.
  1447. 2) pass the "no-hlt" option to the kernel
  1448. 3) switch on floating point emulation in the kernel and pass
  1449. the "no387" option to the kernel
  1450. 4) pass the "floppy=nodma" option to the kernel
  1451. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1452. all but the first 4 MB of RAM)
  1453. 6) make sure that the CPU is not over clocked.
  1454. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1455. 8) disable the cache from your BIOS settings
  1456. 9) install a fan for the video card or exchange video RAM
  1457. 10) install a better fan for the CPU
  1458. 11) exchange RAM chips
  1459. 12) exchange the motherboard.
  1460. To compile this driver as a module, choose M here: the
  1461. module will be called apm.
  1462. if APM
  1463. config APM_IGNORE_USER_SUSPEND
  1464. bool "Ignore USER SUSPEND"
  1465. ---help---
  1466. This option will ignore USER SUSPEND requests. On machines with a
  1467. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1468. series notebooks, it is necessary to say Y because of a BIOS bug.
  1469. config APM_DO_ENABLE
  1470. bool "Enable PM at boot time"
  1471. ---help---
  1472. Enable APM features at boot time. From page 36 of the APM BIOS
  1473. specification: "When disabled, the APM BIOS does not automatically
  1474. power manage devices, enter the Standby State, enter the Suspend
  1475. State, or take power saving steps in response to CPU Idle calls."
  1476. This driver will make CPU Idle calls when Linux is idle (unless this
  1477. feature is turned off -- see "Do CPU IDLE calls", below). This
  1478. should always save battery power, but more complicated APM features
  1479. will be dependent on your BIOS implementation. You may need to turn
  1480. this option off if your computer hangs at boot time when using APM
  1481. support, or if it beeps continuously instead of suspending. Turn
  1482. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1483. T400CDT. This is off by default since most machines do fine without
  1484. this feature.
  1485. config APM_CPU_IDLE
  1486. bool "Make CPU Idle calls when idle"
  1487. ---help---
  1488. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1489. On some machines, this can activate improved power savings, such as
  1490. a slowed CPU clock rate, when the machine is idle. These idle calls
  1491. are made after the idle loop has run for some length of time (e.g.,
  1492. 333 mS). On some machines, this will cause a hang at boot time or
  1493. whenever the CPU becomes idle. (On machines with more than one CPU,
  1494. this option does nothing.)
  1495. config APM_DISPLAY_BLANK
  1496. bool "Enable console blanking using APM"
  1497. ---help---
  1498. Enable console blanking using the APM. Some laptops can use this to
  1499. turn off the LCD backlight when the screen blanker of the Linux
  1500. virtual console blanks the screen. Note that this is only used by
  1501. the virtual console screen blanker, and won't turn off the backlight
  1502. when using the X Window system. This also doesn't have anything to
  1503. do with your VESA-compliant power-saving monitor. Further, this
  1504. option doesn't work for all laptops -- it might not turn off your
  1505. backlight at all, or it might print a lot of errors to the console,
  1506. especially if you are using gpm.
  1507. config APM_ALLOW_INTS
  1508. bool "Allow interrupts during APM BIOS calls"
  1509. ---help---
  1510. Normally we disable external interrupts while we are making calls to
  1511. the APM BIOS as a measure to lessen the effects of a badly behaving
  1512. BIOS implementation. The BIOS should reenable interrupts if it
  1513. needs to. Unfortunately, some BIOSes do not -- especially those in
  1514. many of the newer IBM Thinkpads. If you experience hangs when you
  1515. suspend, try setting this to Y. Otherwise, say N.
  1516. endif # APM
  1517. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1518. source "drivers/cpuidle/Kconfig"
  1519. source "drivers/idle/Kconfig"
  1520. endmenu
  1521. menu "Bus options (PCI etc.)"
  1522. config PCI
  1523. bool "PCI support"
  1524. default y
  1525. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1526. ---help---
  1527. Find out whether you have a PCI motherboard. PCI is the name of a
  1528. bus system, i.e. the way the CPU talks to the other stuff inside
  1529. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1530. VESA. If you have PCI, say Y, otherwise N.
  1531. choice
  1532. prompt "PCI access mode"
  1533. depends on X86_32 && PCI
  1534. default PCI_GOANY
  1535. ---help---
  1536. On PCI systems, the BIOS can be used to detect the PCI devices and
  1537. determine their configuration. However, some old PCI motherboards
  1538. have BIOS bugs and may crash if this is done. Also, some embedded
  1539. PCI-based systems don't have any BIOS at all. Linux can also try to
  1540. detect the PCI hardware directly without using the BIOS.
  1541. With this option, you can specify how Linux should detect the
  1542. PCI devices. If you choose "BIOS", the BIOS will be used,
  1543. if you choose "Direct", the BIOS won't be used, and if you
  1544. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1545. If you choose "Any", the kernel will try MMCONFIG, then the
  1546. direct access method and falls back to the BIOS if that doesn't
  1547. work. If unsure, go with the default, which is "Any".
  1548. config PCI_GOBIOS
  1549. bool "BIOS"
  1550. config PCI_GOMMCONFIG
  1551. bool "MMConfig"
  1552. config PCI_GODIRECT
  1553. bool "Direct"
  1554. config PCI_GOOLPC
  1555. bool "OLPC XO-1"
  1556. depends on OLPC
  1557. config PCI_GOANY
  1558. bool "Any"
  1559. endchoice
  1560. config PCI_BIOS
  1561. def_bool y
  1562. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1563. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1564. config PCI_DIRECT
  1565. def_bool y
  1566. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1567. config PCI_MMCONFIG
  1568. def_bool y
  1569. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1570. config PCI_OLPC
  1571. def_bool y
  1572. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1573. config PCI_DOMAINS
  1574. def_bool y
  1575. depends on PCI
  1576. config PCI_MMCONFIG
  1577. bool "Support mmconfig PCI config space access"
  1578. depends on X86_64 && PCI && ACPI
  1579. config PCI_CNB20LE_QUIRK
  1580. bool "Read CNB20LE Host Bridge Windows"
  1581. depends on PCI
  1582. help
  1583. Read the PCI windows out of the CNB20LE host bridge. This allows
  1584. PCI hotplug to work on systems with the CNB20LE chipset which do
  1585. not have ACPI.
  1586. config DMAR
  1587. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1588. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1589. help
  1590. DMA remapping (DMAR) devices support enables independent address
  1591. translations for Direct Memory Access (DMA) from devices.
  1592. These DMA remapping devices are reported via ACPI tables
  1593. and include PCI device scope covered by these DMA
  1594. remapping devices.
  1595. config DMAR_DEFAULT_ON
  1596. def_bool y
  1597. prompt "Enable DMA Remapping Devices by default"
  1598. depends on DMAR
  1599. help
  1600. Selecting this option will enable a DMAR device at boot time if
  1601. one is found. If this option is not selected, DMAR support can
  1602. be enabled by passing intel_iommu=on to the kernel. It is
  1603. recommended you say N here while the DMAR code remains
  1604. experimental.
  1605. config DMAR_BROKEN_GFX_WA
  1606. bool "Workaround broken graphics drivers (going away soon)"
  1607. depends on DMAR && BROKEN
  1608. ---help---
  1609. Current Graphics drivers tend to use physical address
  1610. for DMA and avoid using DMA APIs. Setting this config
  1611. option permits the IOMMU driver to set a unity map for
  1612. all the OS-visible memory. Hence the driver can continue
  1613. to use physical addresses for DMA, at least until this
  1614. option is removed in the 2.6.32 kernel.
  1615. config DMAR_FLOPPY_WA
  1616. def_bool y
  1617. depends on DMAR
  1618. ---help---
  1619. Floppy disk drivers are known to bypass DMA API calls
  1620. thereby failing to work when IOMMU is enabled. This
  1621. workaround will setup a 1:1 mapping for the first
  1622. 16MiB to make floppy (an ISA device) work.
  1623. config INTR_REMAP
  1624. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1625. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1626. ---help---
  1627. Supports Interrupt remapping for IO-APIC and MSI devices.
  1628. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1629. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1630. source "drivers/pci/pcie/Kconfig"
  1631. source "drivers/pci/Kconfig"
  1632. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1633. config ISA_DMA_API
  1634. def_bool y
  1635. if X86_32
  1636. config ISA
  1637. bool "ISA support"
  1638. ---help---
  1639. Find out whether you have ISA slots on your motherboard. ISA is the
  1640. name of a bus system, i.e. the way the CPU talks to the other stuff
  1641. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1642. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1643. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1644. config EISA
  1645. bool "EISA support"
  1646. depends on ISA
  1647. ---help---
  1648. The Extended Industry Standard Architecture (EISA) bus was
  1649. developed as an open alternative to the IBM MicroChannel bus.
  1650. The EISA bus provided some of the features of the IBM MicroChannel
  1651. bus while maintaining backward compatibility with cards made for
  1652. the older ISA bus. The EISA bus saw limited use between 1988 and
  1653. 1995 when it was made obsolete by the PCI bus.
  1654. Say Y here if you are building a kernel for an EISA-based machine.
  1655. Otherwise, say N.
  1656. source "drivers/eisa/Kconfig"
  1657. config MCA
  1658. bool "MCA support"
  1659. ---help---
  1660. MicroChannel Architecture is found in some IBM PS/2 machines and
  1661. laptops. It is a bus system similar to PCI or ISA. See
  1662. <file:Documentation/mca.txt> (and especially the web page given
  1663. there) before attempting to build an MCA bus kernel.
  1664. source "drivers/mca/Kconfig"
  1665. config SCx200
  1666. tristate "NatSemi SCx200 support"
  1667. ---help---
  1668. This provides basic support for National Semiconductor's
  1669. (now AMD's) Geode processors. The driver probes for the
  1670. PCI-IDs of several on-chip devices, so its a good dependency
  1671. for other scx200_* drivers.
  1672. If compiled as a module, the driver is named scx200.
  1673. config SCx200HR_TIMER
  1674. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1675. depends on SCx200
  1676. default y
  1677. ---help---
  1678. This driver provides a clocksource built upon the on-chip
  1679. 27MHz high-resolution timer. Its also a workaround for
  1680. NSC Geode SC-1100's buggy TSC, which loses time when the
  1681. processor goes idle (as is done by the scheduler). The
  1682. other workaround is idle=poll boot option.
  1683. config OLPC
  1684. bool "One Laptop Per Child support"
  1685. select GPIOLIB
  1686. select OLPC_OPENFIRMWARE
  1687. ---help---
  1688. Add support for detecting the unique features of the OLPC
  1689. XO hardware.
  1690. config OLPC_XO1
  1691. tristate "OLPC XO-1 support"
  1692. depends on OLPC && PCI
  1693. ---help---
  1694. Add support for non-essential features of the OLPC XO-1 laptop.
  1695. config OLPC_OPENFIRMWARE
  1696. bool "Support for OLPC's Open Firmware"
  1697. depends on !X86_64 && !X86_PAE
  1698. default n
  1699. help
  1700. This option adds support for the implementation of Open Firmware
  1701. that is used on the OLPC XO-1 Children's Machine.
  1702. If unsure, say N here.
  1703. endif # X86_32
  1704. config AMD_NB
  1705. def_bool y
  1706. depends on CPU_SUP_AMD && PCI
  1707. source "drivers/pcmcia/Kconfig"
  1708. source "drivers/pci/hotplug/Kconfig"
  1709. endmenu
  1710. menu "Executable file formats / Emulations"
  1711. source "fs/Kconfig.binfmt"
  1712. config IA32_EMULATION
  1713. bool "IA32 Emulation"
  1714. depends on X86_64
  1715. select COMPAT_BINFMT_ELF
  1716. ---help---
  1717. Include code to run 32-bit programs under a 64-bit kernel. You should
  1718. likely turn this on, unless you're 100% sure that you don't have any
  1719. 32-bit programs left.
  1720. config IA32_AOUT
  1721. tristate "IA32 a.out support"
  1722. depends on IA32_EMULATION
  1723. ---help---
  1724. Support old a.out binaries in the 32bit emulation.
  1725. config COMPAT
  1726. def_bool y
  1727. depends on IA32_EMULATION
  1728. config COMPAT_FOR_U64_ALIGNMENT
  1729. def_bool COMPAT
  1730. depends on X86_64
  1731. config SYSVIPC_COMPAT
  1732. def_bool y
  1733. depends on COMPAT && SYSVIPC
  1734. endmenu
  1735. config HAVE_ATOMIC_IOMAP
  1736. def_bool y
  1737. depends on X86_32
  1738. config HAVE_TEXT_POKE_SMP
  1739. bool
  1740. select STOP_MACHINE if SMP
  1741. source "net/Kconfig"
  1742. source "drivers/Kconfig"
  1743. source "drivers/firmware/Kconfig"
  1744. source "fs/Kconfig"
  1745. source "arch/x86/Kconfig.debug"
  1746. source "security/Kconfig"
  1747. source "crypto/Kconfig"
  1748. source "arch/x86/kvm/Kconfig"
  1749. source "lib/Kconfig"