Kconfig 66 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991001011021031041051061071081091101111121131141151161171181191201211221231241251261271281291301311321331341351361371381391401411421431441451461471481491501511521531541551561571581591601611621631641651661671681691701711721731741751761771781791801811821831841851861871881891901911921931941951961971981992002012022032042052062072082092102112122132142152162172182192202212222232242252262272282292302312322332342352362372382392402412422432442452462472482492502512522532542552562572582592602612622632642652662672682692702712722732742752762772782792802812822832842852862872882892902912922932942952962972982993003013023033043053063073083093103113123133143153163173183193203213223233243253263273283293303313323333343353363373383393403413423433443453463473483493503513523533543553563573583593603613623633643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943953963973983994004014024034044054064074084094104114124134144154164174184194204214224234244254264274284294304314324334344354364374384394404414424434444454464474484494504514524534544554564574584594604614624634644654664674684694704714724734744754764774784794804814824834844854864874884894904914924934944954964974984995005015025035045055065075085095105115125135145155165175185195205215225235245255265275285295305315325335345355365375385395405415425435445455465475485495505515525535545555565575585595605615625635645655665675685695705715725735745755765775785795805815825835845855865875885895905915925935945955965975985996006016026036046056066076086096106116126136146156166176186196206216226236246256266276286296306316326336346356366376386396406416426436446456466476486496506516526536546556566576586596606616626636646656666676686696706716726736746756766776786796806816826836846856866876886896906916926936946956966976986997007017027037047057067077087097107117127137147157167177187197207217227237247257267277287297307317327337347357367377387397407417427437447457467477487497507517527537547557567577587597607617627637647657667677687697707717727737747757767777787797807817827837847857867877887897907917927937947957967977987998008018028038048058068078088098108118128138148158168178188198208218228238248258268278288298308318328338348358368378388398408418428438448458468478488498508518528538548558568578588598608618628638648658668678688698708718728738748758768778788798808818828838848858868878888898908918928938948958968978988999009019029039049059069079089099109119129139149159169179189199209219229239249259269279289299309319329339349359369379389399409419429439449459469479489499509519529539549559569579589599609619629639649659669679689699709719729739749759769779789799809819829839849859869879889899909919929939949959969979989991000100110021003100410051006100710081009101010111012101310141015101610171018101910201021102210231024102510261027102810291030103110321033103410351036103710381039104010411042104310441045104610471048104910501051105210531054105510561057105810591060106110621063106410651066106710681069107010711072107310741075107610771078107910801081108210831084108510861087108810891090109110921093109410951096109710981099110011011102110311041105110611071108110911101111111211131114111511161117111811191120112111221123112411251126112711281129113011311132113311341135113611371138113911401141114211431144114511461147114811491150115111521153115411551156115711581159116011611162116311641165116611671168116911701171117211731174117511761177117811791180118111821183118411851186118711881189119011911192119311941195119611971198119912001201120212031204120512061207120812091210121112121213121412151216121712181219122012211222122312241225122612271228122912301231123212331234123512361237123812391240124112421243124412451246124712481249125012511252125312541255125612571258125912601261126212631264126512661267126812691270127112721273127412751276127712781279128012811282128312841285128612871288128912901291129212931294129512961297129812991300130113021303130413051306130713081309131013111312131313141315131613171318131913201321132213231324132513261327132813291330133113321333133413351336133713381339134013411342134313441345134613471348134913501351135213531354135513561357135813591360136113621363136413651366136713681369137013711372137313741375137613771378137913801381138213831384138513861387138813891390139113921393139413951396139713981399140014011402140314041405140614071408140914101411141214131414141514161417141814191420142114221423142414251426142714281429143014311432143314341435143614371438143914401441144214431444144514461447144814491450145114521453145414551456145714581459146014611462146314641465146614671468146914701471147214731474147514761477147814791480148114821483148414851486148714881489149014911492149314941495149614971498149915001501150215031504150515061507150815091510151115121513151415151516151715181519152015211522152315241525152615271528152915301531153215331534153515361537153815391540154115421543154415451546154715481549155015511552155315541555155615571558155915601561156215631564156515661567156815691570157115721573157415751576157715781579158015811582158315841585158615871588158915901591159215931594159515961597159815991600160116021603160416051606160716081609161016111612161316141615161616171618161916201621162216231624162516261627162816291630163116321633163416351636163716381639164016411642164316441645164616471648164916501651165216531654165516561657165816591660166116621663166416651666166716681669167016711672167316741675167616771678167916801681168216831684168516861687168816891690169116921693169416951696169716981699170017011702170317041705170617071708170917101711171217131714171517161717171817191720172117221723172417251726172717281729173017311732173317341735173617371738173917401741174217431744174517461747174817491750175117521753175417551756175717581759176017611762176317641765176617671768176917701771177217731774177517761777177817791780178117821783178417851786178717881789179017911792179317941795179617971798179918001801180218031804180518061807180818091810181118121813181418151816181718181819182018211822182318241825182618271828182918301831183218331834183518361837183818391840184118421843184418451846184718481849185018511852185318541855185618571858185918601861186218631864186518661867186818691870187118721873187418751876187718781879188018811882188318841885188618871888188918901891189218931894189518961897189818991900190119021903190419051906190719081909191019111912191319141915191619171918191919201921192219231924192519261927192819291930193119321933193419351936193719381939194019411942194319441945194619471948194919501951195219531954195519561957195819591960196119621963196419651966196719681969197019711972197319741975197619771978197919801981198219831984198519861987198819891990199119921993199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026202720282029203020312032203320342035203620372038203920402041204220432044204520462047204820492050205120522053205420552056205720582059206020612062206320642065206620672068206920702071207220732074207520762077207820792080208120822083208420852086208720882089209020912092209320942095209620972098209921002101210221032104210521062107
  1. # Select 32 or 64 bit
  2. config 64BIT
  3. bool "64-bit kernel" if ARCH = "x86"
  4. default ARCH = "x86_64"
  5. ---help---
  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. config X86_32
  9. def_bool !64BIT
  10. select CLKSRC_I8253
  11. config X86_64
  12. def_bool 64BIT
  13. ### Arch settings
  14. config X86
  15. def_bool y
  16. select HAVE_AOUT if X86_32
  17. select HAVE_UNSTABLE_SCHED_CLOCK
  18. select HAVE_IDE
  19. select HAVE_OPROFILE
  20. select HAVE_PCSPKR_PLATFORM
  21. select HAVE_PERF_EVENTS
  22. select HAVE_IRQ_WORK
  23. select HAVE_IOREMAP_PROT
  24. select HAVE_KPROBES
  25. select HAVE_MEMBLOCK
  26. select ARCH_WANT_OPTIONAL_GPIOLIB
  27. select ARCH_WANT_FRAME_POINTERS
  28. select HAVE_DMA_ATTRS
  29. select HAVE_KRETPROBES
  30. select HAVE_OPTPROBES
  31. select HAVE_FTRACE_MCOUNT_RECORD
  32. select HAVE_C_RECORDMCOUNT
  33. select HAVE_DYNAMIC_FTRACE
  34. select HAVE_FUNCTION_TRACER
  35. select HAVE_FUNCTION_GRAPH_TRACER
  36. select HAVE_FUNCTION_GRAPH_FP_TEST
  37. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  38. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  39. select HAVE_SYSCALL_TRACEPOINTS
  40. select HAVE_KVM
  41. select HAVE_ARCH_KGDB
  42. select HAVE_ARCH_TRACEHOOK
  43. select HAVE_GENERIC_DMA_COHERENT if X86_32
  44. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  45. select USER_STACKTRACE_SUPPORT
  46. select HAVE_REGS_AND_STACK_ACCESS_API
  47. select HAVE_DMA_API_DEBUG
  48. select HAVE_KERNEL_GZIP
  49. select HAVE_KERNEL_BZIP2
  50. select HAVE_KERNEL_LZMA
  51. select HAVE_KERNEL_XZ
  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_FIND_FIRST_BIT
  65. select GENERIC_IRQ_PROBE
  66. select GENERIC_PENDING_IRQ if SMP
  67. select GENERIC_IRQ_SHOW
  68. select IRQ_FORCED_THREADING
  69. select USE_GENERIC_SMP_HELPERS if SMP
  70. select HAVE_BPF_JIT if (X86_64 && NET)
  71. select CLKEVT_I8253
  72. config INSTRUCTION_DECODER
  73. def_bool (KPROBES || PERF_EVENTS)
  74. config OUTPUT_FORMAT
  75. string
  76. default "elf32-i386" if X86_32
  77. default "elf64-x86-64" if X86_64
  78. config ARCH_DEFCONFIG
  79. string
  80. default "arch/x86/configs/i386_defconfig" if X86_32
  81. default "arch/x86/configs/x86_64_defconfig" if X86_64
  82. config GENERIC_CMOS_UPDATE
  83. def_bool y
  84. config CLOCKSOURCE_WATCHDOG
  85. def_bool y
  86. config GENERIC_CLOCKEVENTS
  87. def_bool y
  88. config ARCH_CLOCKSOURCE_DATA
  89. def_bool y
  90. depends on X86_64
  91. config GENERIC_CLOCKEVENTS_BROADCAST
  92. def_bool y
  93. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  94. config LOCKDEP_SUPPORT
  95. def_bool y
  96. config STACKTRACE_SUPPORT
  97. def_bool y
  98. config HAVE_LATENCYTOP_SUPPORT
  99. def_bool y
  100. config MMU
  101. def_bool y
  102. config ZONE_DMA
  103. bool "DMA memory allocation support" if EXPERT
  104. default y
  105. help
  106. DMA memory allocation support allows devices with less than 32-bit
  107. addressing to allocate within the first 16MB of address space.
  108. Disable if no such devices will be used.
  109. If unsure, say Y.
  110. config SBUS
  111. bool
  112. config NEED_DMA_MAP_STATE
  113. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  114. config NEED_SG_DMA_LENGTH
  115. def_bool y
  116. config GENERIC_ISA_DMA
  117. def_bool ISA_DMA_API
  118. config GENERIC_IOMAP
  119. def_bool y
  120. config GENERIC_BUG
  121. def_bool y
  122. depends on BUG
  123. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  124. config GENERIC_BUG_RELATIVE_POINTERS
  125. bool
  126. config GENERIC_HWEIGHT
  127. def_bool y
  128. config GENERIC_GPIO
  129. bool
  130. config ARCH_MAY_HAVE_PC_FDC
  131. def_bool ISA_DMA_API
  132. config RWSEM_GENERIC_SPINLOCK
  133. def_bool !X86_XADD
  134. config RWSEM_XCHGADD_ALGORITHM
  135. def_bool X86_XADD
  136. config ARCH_HAS_CPU_IDLE_WAIT
  137. def_bool y
  138. config GENERIC_CALIBRATE_DELAY
  139. def_bool y
  140. config GENERIC_TIME_VSYSCALL
  141. bool
  142. default X86_64
  143. config ARCH_HAS_CPU_RELAX
  144. def_bool y
  145. config ARCH_HAS_DEFAULT_IDLE
  146. def_bool y
  147. config ARCH_HAS_CACHE_LINE_SIZE
  148. def_bool y
  149. config HAVE_SETUP_PER_CPU_AREA
  150. def_bool y
  151. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  152. def_bool y
  153. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  154. def_bool y
  155. config HAVE_CPUMASK_OF_CPU_MAP
  156. def_bool X86_64_SMP
  157. config ARCH_HIBERNATION_POSSIBLE
  158. def_bool y
  159. config ARCH_SUSPEND_POSSIBLE
  160. def_bool y
  161. config ZONE_DMA32
  162. bool
  163. default X86_64
  164. config ARCH_POPULATES_NODE_MAP
  165. def_bool y
  166. config AUDIT_ARCH
  167. bool
  168. default X86_64
  169. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  170. def_bool y
  171. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  172. def_bool y
  173. config HAVE_INTEL_TXT
  174. def_bool y
  175. depends on EXPERIMENTAL && DMAR && ACPI
  176. config X86_32_SMP
  177. def_bool y
  178. depends on X86_32 && SMP
  179. config X86_64_SMP
  180. def_bool y
  181. depends on X86_64 && SMP
  182. config X86_HT
  183. def_bool y
  184. depends on SMP
  185. config X86_32_LAZY_GS
  186. def_bool y
  187. depends on X86_32 && !CC_STACKPROTECTOR
  188. config ARCH_HWEIGHT_CFLAGS
  189. string
  190. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  191. 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
  192. config KTIME_SCALAR
  193. def_bool X86_32
  194. config ARCH_CPU_PROBE_RELEASE
  195. def_bool y
  196. depends on HOTPLUG_CPU
  197. source "init/Kconfig"
  198. source "kernel/Kconfig.freezer"
  199. menu "Processor type and features"
  200. source "kernel/time/Kconfig"
  201. config SMP
  202. bool "Symmetric multi-processing support"
  203. ---help---
  204. This enables support for systems with more than one CPU. If you have
  205. a system with only one CPU, like most personal computers, say N. If
  206. you have a system with more than one CPU, say Y.
  207. If you say N here, the kernel will run on single and multiprocessor
  208. machines, but will use only one CPU of a multiprocessor machine. If
  209. you say Y here, the kernel will run on many, but not all,
  210. singleprocessor machines. On a singleprocessor machine, the kernel
  211. will run faster if you say N here.
  212. Note that if you say Y here and choose architecture "586" or
  213. "Pentium" under "Processor family", the kernel will not work on 486
  214. architectures. Similarly, multiprocessor kernels for the "PPro"
  215. architecture may not work on all Pentium based boards.
  216. People using multiprocessor machines who say Y here should also say
  217. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  218. Management" code will be disabled if you say Y here.
  219. See also <file:Documentation/i386/IO-APIC.txt>,
  220. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  221. <http://www.tldp.org/docs.html#howto>.
  222. If you don't know what to do here, say N.
  223. config X86_X2APIC
  224. bool "Support x2apic"
  225. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  226. ---help---
  227. This enables x2apic support on CPUs that have this feature.
  228. This allows 32-bit apic IDs (so it can support very large systems),
  229. and accesses the local apic via MSRs not via mmio.
  230. If you don't know what to do here, say N.
  231. config X86_MPPARSE
  232. bool "Enable MPS table" if ACPI
  233. default y
  234. depends on X86_LOCAL_APIC
  235. ---help---
  236. For old smp systems that do not have proper acpi support. Newer systems
  237. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  238. config X86_BIGSMP
  239. bool "Support for big SMP systems with more than 8 CPUs"
  240. depends on X86_32 && SMP
  241. ---help---
  242. This option is needed for the systems that have more than 8 CPUs
  243. if X86_32
  244. config X86_EXTENDED_PLATFORM
  245. bool "Support for extended (non-PC) x86 platforms"
  246. default y
  247. ---help---
  248. If you disable this option then the kernel will only support
  249. standard PC platforms. (which covers the vast majority of
  250. systems out there.)
  251. If you enable this option then you'll be able to select support
  252. for the following (non-PC) 32 bit x86 platforms:
  253. AMD Elan
  254. NUMAQ (IBM/Sequent)
  255. RDC R-321x SoC
  256. SGI 320/540 (Visual Workstation)
  257. Summit/EXA (IBM x440)
  258. Unisys ES7000 IA32 series
  259. Moorestown MID devices
  260. If you have one of these systems, or if you want to build a
  261. generic distribution kernel, say Y here - otherwise say N.
  262. endif
  263. if X86_64
  264. config X86_EXTENDED_PLATFORM
  265. bool "Support for extended (non-PC) x86 platforms"
  266. default y
  267. ---help---
  268. If you disable this option then the kernel will only support
  269. standard PC platforms. (which covers the vast majority of
  270. systems out there.)
  271. If you enable this option then you'll be able to select support
  272. for the following (non-PC) 64 bit x86 platforms:
  273. ScaleMP vSMP
  274. SGI Ultraviolet
  275. If you have one of these systems, or if you want to build a
  276. generic distribution kernel, say Y here - otherwise say N.
  277. endif
  278. # This is an alphabetically sorted list of 64 bit extended platforms
  279. # Please maintain the alphabetic order if and when there are additions
  280. config X86_VSMP
  281. bool "ScaleMP vSMP"
  282. select PARAVIRT_GUEST
  283. select PARAVIRT
  284. depends on X86_64 && PCI
  285. depends on X86_EXTENDED_PLATFORM
  286. ---help---
  287. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  288. supposed to run on these EM64T-based machines. Only choose this option
  289. if you have one of these machines.
  290. config X86_UV
  291. bool "SGI Ultraviolet"
  292. depends on X86_64
  293. depends on X86_EXTENDED_PLATFORM
  294. depends on NUMA
  295. depends on X86_X2APIC
  296. ---help---
  297. This option is needed in order to support SGI Ultraviolet systems.
  298. If you don't have one of these, you should say N here.
  299. # Following is an alphabetically sorted list of 32 bit extended platforms
  300. # Please maintain the alphabetic order if and when there are additions
  301. config X86_INTEL_CE
  302. bool "CE4100 TV platform"
  303. depends on PCI
  304. depends on PCI_GODIRECT
  305. depends on X86_32
  306. depends on X86_EXTENDED_PLATFORM
  307. select X86_REBOOTFIXUPS
  308. select OF
  309. select OF_EARLY_FLATTREE
  310. ---help---
  311. Select for the Intel CE media processor (CE4100) SOC.
  312. This option compiles in support for the CE4100 SOC for settop
  313. boxes and media devices.
  314. config X86_INTEL_MID
  315. bool "Intel MID platform support"
  316. depends on X86_32
  317. depends on X86_EXTENDED_PLATFORM
  318. ---help---
  319. Select to build a kernel capable of supporting Intel MID platform
  320. systems which do not have the PCI legacy interfaces (Moorestown,
  321. Medfield). If you are building for a PC class system say N here.
  322. if X86_INTEL_MID
  323. config X86_MRST
  324. bool "Moorestown MID platform"
  325. depends on PCI
  326. depends on PCI_GOANY
  327. depends on X86_IO_APIC
  328. select APB_TIMER
  329. select I2C
  330. select SPI
  331. select INTEL_SCU_IPC
  332. select X86_PLATFORM_DEVICES
  333. ---help---
  334. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  335. Internet Device(MID) platform. Moorestown consists of two chips:
  336. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  337. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  338. nor standard legacy replacement devices/features. e.g. Moorestown does
  339. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  340. endif
  341. config X86_RDC321X
  342. bool "RDC R-321x SoC"
  343. depends on X86_32
  344. depends on X86_EXTENDED_PLATFORM
  345. select M486
  346. select X86_REBOOTFIXUPS
  347. ---help---
  348. This option is needed for RDC R-321x system-on-chip, also known
  349. as R-8610-(G).
  350. If you don't have one of these chips, you should say N here.
  351. config X86_32_NON_STANDARD
  352. bool "Support non-standard 32-bit SMP architectures"
  353. depends on X86_32 && SMP
  354. depends on X86_EXTENDED_PLATFORM
  355. ---help---
  356. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  357. subarchitectures. It is intended for a generic binary kernel.
  358. if you select them all, kernel will probe it one by one. and will
  359. fallback to default.
  360. # Alphabetically sorted list of Non standard 32 bit platforms
  361. config X86_NUMAQ
  362. bool "NUMAQ (IBM/Sequent)"
  363. depends on X86_32_NON_STANDARD
  364. depends on PCI
  365. select NUMA
  366. select X86_MPPARSE
  367. ---help---
  368. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  369. NUMA multiquad box. This changes the way that processors are
  370. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  371. of Flat Logical. You will need a new lynxer.elf file to flash your
  372. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  373. config X86_SUPPORTS_MEMORY_FAILURE
  374. def_bool y
  375. # MCE code calls memory_failure():
  376. depends on X86_MCE
  377. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  378. depends on !X86_NUMAQ
  379. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  380. depends on X86_64 || !SPARSEMEM
  381. select ARCH_SUPPORTS_MEMORY_FAILURE
  382. config X86_VISWS
  383. bool "SGI 320/540 (Visual Workstation)"
  384. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  385. depends on X86_32_NON_STANDARD
  386. ---help---
  387. The SGI Visual Workstation series is an IA32-based workstation
  388. based on SGI systems chips with some legacy PC hardware attached.
  389. Say Y here to create a kernel to run on the SGI 320 or 540.
  390. A kernel compiled for the Visual Workstation will run on general
  391. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  392. config X86_SUMMIT
  393. bool "Summit/EXA (IBM x440)"
  394. depends on X86_32_NON_STANDARD
  395. ---help---
  396. This option is needed for IBM systems that use the Summit/EXA chipset.
  397. In particular, it is needed for the x440.
  398. config X86_ES7000
  399. bool "Unisys ES7000 IA32 series"
  400. depends on X86_32_NON_STANDARD && X86_BIGSMP
  401. ---help---
  402. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  403. supposed to run on an IA32-based Unisys ES7000 system.
  404. config X86_32_IRIS
  405. tristate "Eurobraille/Iris poweroff module"
  406. depends on X86_32
  407. ---help---
  408. The Iris machines from EuroBraille do not have APM or ACPI support
  409. to shut themselves down properly. A special I/O sequence is
  410. needed to do so, which is what this module does at
  411. kernel shutdown.
  412. This is only for Iris machines from EuroBraille.
  413. If unused, say N.
  414. config SCHED_OMIT_FRAME_POINTER
  415. def_bool y
  416. prompt "Single-depth WCHAN output"
  417. depends on X86
  418. ---help---
  419. Calculate simpler /proc/<PID>/wchan values. If this option
  420. is disabled then wchan values will recurse back to the
  421. caller function. This provides more accurate wchan values,
  422. at the expense of slightly more scheduling overhead.
  423. If in doubt, say "Y".
  424. menuconfig PARAVIRT_GUEST
  425. bool "Paravirtualized guest support"
  426. ---help---
  427. Say Y here to get to see options related to running Linux under
  428. various hypervisors. This option alone does not add any kernel code.
  429. If you say N, all options in this submenu will be skipped and disabled.
  430. if PARAVIRT_GUEST
  431. source "arch/x86/xen/Kconfig"
  432. config KVM_CLOCK
  433. bool "KVM paravirtualized clock"
  434. select PARAVIRT
  435. select PARAVIRT_CLOCK
  436. ---help---
  437. Turning on this option will allow you to run a paravirtualized clock
  438. when running over the KVM hypervisor. Instead of relying on a PIT
  439. (or probably other) emulation by the underlying device model, the host
  440. provides the guest with timing infrastructure such as time of day, and
  441. system time
  442. config KVM_GUEST
  443. bool "KVM Guest support"
  444. select PARAVIRT
  445. ---help---
  446. This option enables various optimizations for running under the KVM
  447. hypervisor.
  448. source "arch/x86/lguest/Kconfig"
  449. config PARAVIRT
  450. bool "Enable paravirtualization code"
  451. ---help---
  452. This changes the kernel so it can modify itself when it is run
  453. under a hypervisor, potentially improving performance significantly
  454. over full virtualization. However, when run without a hypervisor
  455. the kernel is theoretically slower and slightly larger.
  456. config PARAVIRT_SPINLOCKS
  457. bool "Paravirtualization layer for spinlocks"
  458. depends on PARAVIRT && SMP && EXPERIMENTAL
  459. ---help---
  460. Paravirtualized spinlocks allow a pvops backend to replace the
  461. spinlock implementation with something virtualization-friendly
  462. (for example, block the virtual CPU rather than spinning).
  463. Unfortunately the downside is an up to 5% performance hit on
  464. native kernels, with various workloads.
  465. If you are unsure how to answer this question, answer N.
  466. config PARAVIRT_CLOCK
  467. bool
  468. endif
  469. config PARAVIRT_DEBUG
  470. bool "paravirt-ops debugging"
  471. depends on PARAVIRT && DEBUG_KERNEL
  472. ---help---
  473. Enable to debug paravirt_ops internals. Specifically, BUG if
  474. a paravirt_op is missing when it is called.
  475. config NO_BOOTMEM
  476. def_bool y
  477. config MEMTEST
  478. bool "Memtest"
  479. ---help---
  480. This option adds a kernel parameter 'memtest', which allows memtest
  481. to be set.
  482. memtest=0, mean disabled; -- default
  483. memtest=1, mean do 1 test pattern;
  484. ...
  485. memtest=4, mean do 4 test patterns.
  486. If you are unsure how to answer this question, answer N.
  487. config X86_SUMMIT_NUMA
  488. def_bool y
  489. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  490. config X86_CYCLONE_TIMER
  491. def_bool y
  492. depends on X86_32_NON_STANDARD
  493. source "arch/x86/Kconfig.cpu"
  494. config HPET_TIMER
  495. def_bool X86_64
  496. prompt "HPET Timer Support" if X86_32
  497. ---help---
  498. Use the IA-PC HPET (High Precision Event Timer) to manage
  499. time in preference to the PIT and RTC, if a HPET is
  500. present.
  501. HPET is the next generation timer replacing legacy 8254s.
  502. The HPET provides a stable time base on SMP
  503. systems, unlike the TSC, but it is more expensive to access,
  504. as it is off-chip. You can find the HPET spec at
  505. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  506. You can safely choose Y here. However, HPET will only be
  507. activated if the platform and the BIOS support this feature.
  508. Otherwise the 8254 will be used for timing services.
  509. Choose N to continue using the legacy 8254 timer.
  510. config HPET_EMULATE_RTC
  511. def_bool y
  512. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  513. config APB_TIMER
  514. def_bool y if MRST
  515. prompt "Langwell APB Timer Support" if X86_MRST
  516. select DW_APB_TIMER
  517. help
  518. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  519. The APBT provides a stable time base on SMP
  520. systems, unlike the TSC, but it is more expensive to access,
  521. as it is off-chip. APB timers are always running regardless of CPU
  522. C states, they are used as per CPU clockevent device when possible.
  523. # Mark as expert because too many people got it wrong.
  524. # The code disables itself when not needed.
  525. config DMI
  526. default y
  527. bool "Enable DMI scanning" if EXPERT
  528. ---help---
  529. Enabled scanning of DMI to identify machine quirks. Say Y
  530. here unless you have verified that your setup is not
  531. affected by entries in the DMI blacklist. Required by PNP
  532. BIOS code.
  533. config GART_IOMMU
  534. bool "GART IOMMU support" if EXPERT
  535. default y
  536. select SWIOTLB
  537. depends on X86_64 && PCI && AMD_NB
  538. ---help---
  539. Support for full DMA access of devices with 32bit memory access only
  540. on systems with more than 3GB. This is usually needed for USB,
  541. sound, many IDE/SATA chipsets and some other devices.
  542. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  543. based hardware IOMMU and a software bounce buffer based IOMMU used
  544. on Intel systems and as fallback.
  545. The code is only active when needed (enough memory and limited
  546. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  547. too.
  548. config CALGARY_IOMMU
  549. bool "IBM Calgary IOMMU support"
  550. select SWIOTLB
  551. depends on X86_64 && PCI && EXPERIMENTAL
  552. ---help---
  553. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  554. systems. Needed to run systems with more than 3GB of memory
  555. properly with 32-bit PCI devices that do not support DAC
  556. (Double Address Cycle). Calgary also supports bus level
  557. isolation, where all DMAs pass through the IOMMU. This
  558. prevents them from going anywhere except their intended
  559. destination. This catches hard-to-find kernel bugs and
  560. mis-behaving drivers and devices that do not use the DMA-API
  561. properly to set up their DMA buffers. The IOMMU can be
  562. turned off at boot time with the iommu=off parameter.
  563. Normally the kernel will make the right choice by itself.
  564. If unsure, say Y.
  565. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  566. def_bool y
  567. prompt "Should Calgary be enabled by default?"
  568. depends on CALGARY_IOMMU
  569. ---help---
  570. Should Calgary be enabled by default? if you choose 'y', Calgary
  571. will be used (if it exists). If you choose 'n', Calgary will not be
  572. used even if it exists. If you choose 'n' and would like to use
  573. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  574. If unsure, say Y.
  575. # need this always selected by IOMMU for the VIA workaround
  576. config SWIOTLB
  577. def_bool y if X86_64
  578. ---help---
  579. Support for software bounce buffers used on x86-64 systems
  580. which don't have a hardware IOMMU (e.g. the current generation
  581. of Intel's x86-64 CPUs). Using this PCI devices which can only
  582. access 32-bits of memory can be used on systems with more than
  583. 3 GB of memory. If unsure, say Y.
  584. config IOMMU_HELPER
  585. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  586. config MAXSMP
  587. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  588. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  589. select CPUMASK_OFFSTACK
  590. ---help---
  591. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  592. If unsure, say N.
  593. config NR_CPUS
  594. int "Maximum number of CPUs" if SMP && !MAXSMP
  595. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  596. range 2 512 if SMP && !MAXSMP
  597. default "1" if !SMP
  598. default "4096" if MAXSMP
  599. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  600. default "8" if SMP
  601. ---help---
  602. This allows you to specify the maximum number of CPUs which this
  603. kernel will support. The maximum supported value is 512 and the
  604. minimum value which makes sense is 2.
  605. This is purely to save memory - each supported CPU adds
  606. approximately eight kilobytes to the kernel image.
  607. config SCHED_SMT
  608. bool "SMT (Hyperthreading) scheduler support"
  609. depends on X86_HT
  610. ---help---
  611. SMT scheduler support improves the CPU scheduler's decision making
  612. when dealing with Intel Pentium 4 chips with HyperThreading at a
  613. cost of slightly increased overhead in some places. If unsure say
  614. N here.
  615. config SCHED_MC
  616. def_bool y
  617. prompt "Multi-core scheduler support"
  618. depends on X86_HT
  619. ---help---
  620. Multi-core scheduler support improves the CPU scheduler's decision
  621. making when dealing with multi-core CPU chips at a cost of slightly
  622. increased overhead in some places. If unsure say N here.
  623. config IRQ_TIME_ACCOUNTING
  624. bool "Fine granularity task level IRQ time accounting"
  625. default n
  626. ---help---
  627. Select this option to enable fine granularity task irq time
  628. accounting. This is done by reading a timestamp on each
  629. transitions between softirq and hardirq state, so there can be a
  630. small performance impact.
  631. If in doubt, say N here.
  632. source "kernel/Kconfig.preempt"
  633. config X86_UP_APIC
  634. bool "Local APIC support on uniprocessors"
  635. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  636. ---help---
  637. A local APIC (Advanced Programmable Interrupt Controller) is an
  638. integrated interrupt controller in the CPU. If you have a single-CPU
  639. system which has a processor with a local APIC, you can say Y here to
  640. enable and use it. If you say Y here even though your machine doesn't
  641. have a local APIC, then the kernel will still run with no slowdown at
  642. all. The local APIC supports CPU-generated self-interrupts (timer,
  643. performance counters), and the NMI watchdog which detects hard
  644. lockups.
  645. config X86_UP_IOAPIC
  646. bool "IO-APIC support on uniprocessors"
  647. depends on X86_UP_APIC
  648. ---help---
  649. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  650. SMP-capable replacement for PC-style interrupt controllers. Most
  651. SMP systems and many recent uniprocessor systems have one.
  652. If you have a single-CPU system with an IO-APIC, you can say Y here
  653. to use it. If you say Y here even though your machine doesn't have
  654. an IO-APIC, then the kernel will still run with no slowdown at all.
  655. config X86_LOCAL_APIC
  656. def_bool y
  657. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  658. config X86_IO_APIC
  659. def_bool y
  660. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
  661. config X86_VISWS_APIC
  662. def_bool y
  663. depends on X86_32 && X86_VISWS
  664. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  665. bool "Reroute for broken boot IRQs"
  666. depends on X86_IO_APIC
  667. ---help---
  668. This option enables a workaround that fixes a source of
  669. spurious interrupts. This is recommended when threaded
  670. interrupt handling is used on systems where the generation of
  671. superfluous "boot interrupts" cannot be disabled.
  672. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  673. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  674. kernel does during interrupt handling). On chipsets where this
  675. boot IRQ generation cannot be disabled, this workaround keeps
  676. the original IRQ line masked so that only the equivalent "boot
  677. IRQ" is delivered to the CPUs. The workaround also tells the
  678. kernel to set up the IRQ handler on the boot IRQ line. In this
  679. way only one interrupt is delivered to the kernel. Otherwise
  680. the spurious second interrupt may cause the kernel to bring
  681. down (vital) interrupt lines.
  682. Only affects "broken" chipsets. Interrupt sharing may be
  683. increased on these systems.
  684. config X86_MCE
  685. bool "Machine Check / overheating reporting"
  686. ---help---
  687. Machine Check support allows the processor to notify the
  688. kernel if it detects a problem (e.g. overheating, data corruption).
  689. The action the kernel takes depends on the severity of the problem,
  690. ranging from warning messages to halting the machine.
  691. config X86_MCE_INTEL
  692. def_bool y
  693. prompt "Intel MCE features"
  694. depends on X86_MCE && X86_LOCAL_APIC
  695. ---help---
  696. Additional support for intel specific MCE features such as
  697. the thermal monitor.
  698. config X86_MCE_AMD
  699. def_bool y
  700. prompt "AMD MCE features"
  701. depends on X86_MCE && X86_LOCAL_APIC
  702. ---help---
  703. Additional support for AMD specific MCE features such as
  704. the DRAM Error Threshold.
  705. config X86_ANCIENT_MCE
  706. bool "Support for old Pentium 5 / WinChip machine checks"
  707. depends on X86_32 && X86_MCE
  708. ---help---
  709. Include support for machine check handling on old Pentium 5 or WinChip
  710. systems. These typically need to be enabled explicitely on the command
  711. line.
  712. config X86_MCE_THRESHOLD
  713. depends on X86_MCE_AMD || X86_MCE_INTEL
  714. def_bool y
  715. config X86_MCE_INJECT
  716. depends on X86_MCE
  717. tristate "Machine check injector support"
  718. ---help---
  719. Provide support for injecting machine checks for testing purposes.
  720. If you don't know what a machine check is and you don't do kernel
  721. QA it is safe to say n.
  722. config X86_THERMAL_VECTOR
  723. def_bool y
  724. depends on X86_MCE_INTEL
  725. config VM86
  726. bool "Enable VM86 support" if EXPERT
  727. default y
  728. depends on X86_32
  729. ---help---
  730. This option is required by programs like DOSEMU to run 16-bit legacy
  731. code on X86 processors. It also may be needed by software like
  732. XFree86 to initialize some video cards via BIOS. Disabling this
  733. option saves about 6k.
  734. config TOSHIBA
  735. tristate "Toshiba Laptop support"
  736. depends on X86_32
  737. ---help---
  738. This adds a driver to safely access the System Management Mode of
  739. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  740. not work on models with a Phoenix BIOS. The System Management Mode
  741. is used to set the BIOS and power saving options on Toshiba portables.
  742. For information on utilities to make use of this driver see the
  743. Toshiba Linux utilities web site at:
  744. <http://www.buzzard.org.uk/toshiba/>.
  745. Say Y if you intend to run this kernel on a Toshiba portable.
  746. Say N otherwise.
  747. config I8K
  748. tristate "Dell laptop support"
  749. select HWMON
  750. ---help---
  751. This adds a driver to safely access the System Management Mode
  752. of the CPU on the Dell Inspiron 8000. The System Management Mode
  753. is used to read cpu temperature and cooling fan status and to
  754. control the fans on the I8K portables.
  755. This driver has been tested only on the Inspiron 8000 but it may
  756. also work with other Dell laptops. You can force loading on other
  757. models by passing the parameter `force=1' to the module. Use at
  758. your own risk.
  759. For information on utilities to make use of this driver see the
  760. I8K Linux utilities web site at:
  761. <http://people.debian.org/~dz/i8k/>
  762. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  763. Say N otherwise.
  764. config X86_REBOOTFIXUPS
  765. bool "Enable X86 board specific fixups for reboot"
  766. depends on X86_32
  767. ---help---
  768. This enables chipset and/or board specific fixups to be done
  769. in order to get reboot to work correctly. This is only needed on
  770. some combinations of hardware and BIOS. The symptom, for which
  771. this config is intended, is when reboot ends with a stalled/hung
  772. system.
  773. Currently, the only fixup is for the Geode machines using
  774. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  775. Say Y if you want to enable the fixup. Currently, it's safe to
  776. enable this option even if you don't need it.
  777. Say N otherwise.
  778. config MICROCODE
  779. tristate "/dev/cpu/microcode - microcode support"
  780. select FW_LOADER
  781. ---help---
  782. If you say Y here, you will be able to update the microcode on
  783. certain Intel and AMD processors. The Intel support is for the
  784. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  785. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  786. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  787. You will obviously need the actual microcode binary data itself
  788. which is not shipped with the Linux kernel.
  789. This option selects the general module only, you need to select
  790. at least one vendor specific module as well.
  791. To compile this driver as a module, choose M here: the
  792. module will be called microcode.
  793. config MICROCODE_INTEL
  794. bool "Intel microcode patch loading support"
  795. depends on MICROCODE
  796. default MICROCODE
  797. select FW_LOADER
  798. ---help---
  799. This options enables microcode patch loading support for Intel
  800. processors.
  801. For latest news and information on obtaining all the required
  802. Intel ingredients for this driver, check:
  803. <http://www.urbanmyth.org/microcode/>.
  804. config MICROCODE_AMD
  805. bool "AMD microcode patch loading support"
  806. depends on MICROCODE
  807. select FW_LOADER
  808. ---help---
  809. If you select this option, microcode patch loading support for AMD
  810. processors will be enabled.
  811. config MICROCODE_OLD_INTERFACE
  812. def_bool y
  813. depends on MICROCODE
  814. config X86_MSR
  815. tristate "/dev/cpu/*/msr - Model-specific register support"
  816. ---help---
  817. This device gives privileged processes access to the x86
  818. Model-Specific Registers (MSRs). It is a character device with
  819. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  820. MSR accesses are directed to a specific CPU on multi-processor
  821. systems.
  822. config X86_CPUID
  823. tristate "/dev/cpu/*/cpuid - CPU information support"
  824. ---help---
  825. This device gives processes access to the x86 CPUID instruction to
  826. be executed on a specific processor. It is a character device
  827. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  828. /dev/cpu/31/cpuid.
  829. choice
  830. prompt "High Memory Support"
  831. default HIGHMEM64G if X86_NUMAQ
  832. default HIGHMEM4G
  833. depends on X86_32
  834. config NOHIGHMEM
  835. bool "off"
  836. depends on !X86_NUMAQ
  837. ---help---
  838. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  839. However, the address space of 32-bit x86 processors is only 4
  840. Gigabytes large. That means that, if you have a large amount of
  841. physical memory, not all of it can be "permanently mapped" by the
  842. kernel. The physical memory that's not permanently mapped is called
  843. "high memory".
  844. If you are compiling a kernel which will never run on a machine with
  845. more than 1 Gigabyte total physical RAM, answer "off" here (default
  846. choice and suitable for most users). This will result in a "3GB/1GB"
  847. split: 3GB are mapped so that each process sees a 3GB virtual memory
  848. space and the remaining part of the 4GB virtual memory space is used
  849. by the kernel to permanently map as much physical memory as
  850. possible.
  851. If the machine has between 1 and 4 Gigabytes physical RAM, then
  852. answer "4GB" here.
  853. If more than 4 Gigabytes is used then answer "64GB" here. This
  854. selection turns Intel PAE (Physical Address Extension) mode on.
  855. PAE implements 3-level paging on IA32 processors. PAE is fully
  856. supported by Linux, PAE mode is implemented on all recent Intel
  857. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  858. then the kernel will not boot on CPUs that don't support PAE!
  859. The actual amount of total physical memory will either be
  860. auto detected or can be forced by using a kernel command line option
  861. such as "mem=256M". (Try "man bootparam" or see the documentation of
  862. your boot loader (lilo or loadlin) about how to pass options to the
  863. kernel at boot time.)
  864. If unsure, say "off".
  865. config HIGHMEM4G
  866. bool "4GB"
  867. depends on !X86_NUMAQ
  868. ---help---
  869. Select this if you have a 32-bit processor and between 1 and 4
  870. gigabytes of physical RAM.
  871. config HIGHMEM64G
  872. bool "64GB"
  873. depends on !M386 && !M486
  874. select X86_PAE
  875. ---help---
  876. Select this if you have a 32-bit processor and more than 4
  877. gigabytes of physical RAM.
  878. endchoice
  879. choice
  880. depends on EXPERIMENTAL
  881. prompt "Memory split" if EXPERT
  882. default VMSPLIT_3G
  883. depends on X86_32
  884. ---help---
  885. Select the desired split between kernel and user memory.
  886. If the address range available to the kernel is less than the
  887. physical memory installed, the remaining memory will be available
  888. as "high memory". Accessing high memory is a little more costly
  889. than low memory, as it needs to be mapped into the kernel first.
  890. Note that increasing the kernel address space limits the range
  891. available to user programs, making the address space there
  892. tighter. Selecting anything other than the default 3G/1G split
  893. will also likely make your kernel incompatible with binary-only
  894. kernel modules.
  895. If you are not absolutely sure what you are doing, leave this
  896. option alone!
  897. config VMSPLIT_3G
  898. bool "3G/1G user/kernel split"
  899. config VMSPLIT_3G_OPT
  900. depends on !X86_PAE
  901. bool "3G/1G user/kernel split (for full 1G low memory)"
  902. config VMSPLIT_2G
  903. bool "2G/2G user/kernel split"
  904. config VMSPLIT_2G_OPT
  905. depends on !X86_PAE
  906. bool "2G/2G user/kernel split (for full 2G low memory)"
  907. config VMSPLIT_1G
  908. bool "1G/3G user/kernel split"
  909. endchoice
  910. config PAGE_OFFSET
  911. hex
  912. default 0xB0000000 if VMSPLIT_3G_OPT
  913. default 0x80000000 if VMSPLIT_2G
  914. default 0x78000000 if VMSPLIT_2G_OPT
  915. default 0x40000000 if VMSPLIT_1G
  916. default 0xC0000000
  917. depends on X86_32
  918. config HIGHMEM
  919. def_bool y
  920. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  921. config X86_PAE
  922. bool "PAE (Physical Address Extension) Support"
  923. depends on X86_32 && !HIGHMEM4G
  924. ---help---
  925. PAE is required for NX support, and furthermore enables
  926. larger swapspace support for non-overcommit purposes. It
  927. has the cost of more pagetable lookup overhead, and also
  928. consumes more pagetable space per process.
  929. config ARCH_PHYS_ADDR_T_64BIT
  930. def_bool X86_64 || X86_PAE
  931. config ARCH_DMA_ADDR_T_64BIT
  932. def_bool X86_64 || HIGHMEM64G
  933. config DIRECT_GBPAGES
  934. bool "Enable 1GB pages for kernel pagetables" if EXPERT
  935. default y
  936. depends on X86_64
  937. ---help---
  938. Allow the kernel linear mapping to use 1GB pages on CPUs that
  939. support it. This can improve the kernel's performance a tiny bit by
  940. reducing TLB pressure. If in doubt, say "Y".
  941. # Common NUMA Features
  942. config NUMA
  943. bool "Numa Memory Allocation and Scheduler Support"
  944. depends on SMP
  945. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  946. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  947. ---help---
  948. Enable NUMA (Non Uniform Memory Access) support.
  949. The kernel will try to allocate memory used by a CPU on the
  950. local memory controller of the CPU and add some more
  951. NUMA awareness to the kernel.
  952. For 64-bit this is recommended if the system is Intel Core i7
  953. (or later), AMD Opteron, or EM64T NUMA.
  954. For 32-bit this is only needed on (rare) 32-bit-only platforms
  955. that support NUMA topologies, such as NUMAQ / Summit, or if you
  956. boot a 32-bit kernel on a 64-bit NUMA platform.
  957. Otherwise, you should say N.
  958. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  959. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  960. config AMD_NUMA
  961. def_bool y
  962. prompt "Old style AMD Opteron NUMA detection"
  963. depends on X86_64 && NUMA && PCI
  964. ---help---
  965. Enable AMD NUMA node topology detection. You should say Y here if
  966. you have a multi processor AMD system. This uses an old method to
  967. read the NUMA configuration directly from the builtin Northbridge
  968. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  969. which also takes priority if both are compiled in.
  970. config X86_64_ACPI_NUMA
  971. def_bool y
  972. prompt "ACPI NUMA detection"
  973. depends on X86_64 && NUMA && ACPI && PCI
  974. select ACPI_NUMA
  975. ---help---
  976. Enable ACPI SRAT based node topology detection.
  977. # Some NUMA nodes have memory ranges that span
  978. # other nodes. Even though a pfn is valid and
  979. # between a node's start and end pfns, it may not
  980. # reside on that node. See memmap_init_zone()
  981. # for details.
  982. config NODES_SPAN_OTHER_NODES
  983. def_bool y
  984. depends on X86_64_ACPI_NUMA
  985. config NUMA_EMU
  986. bool "NUMA emulation"
  987. depends on NUMA
  988. ---help---
  989. Enable NUMA emulation. A flat machine will be split
  990. into virtual nodes when booted with "numa=fake=N", where N is the
  991. number of nodes. This is only useful for debugging.
  992. config NODES_SHIFT
  993. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  994. range 1 10
  995. default "10" if MAXSMP
  996. default "6" if X86_64
  997. default "4" if X86_NUMAQ
  998. default "3"
  999. depends on NEED_MULTIPLE_NODES
  1000. ---help---
  1001. Specify the maximum number of NUMA Nodes available on the target
  1002. system. Increases memory reserved to accommodate various tables.
  1003. config HAVE_ARCH_BOOTMEM
  1004. def_bool y
  1005. depends on X86_32 && NUMA
  1006. config HAVE_ARCH_ALLOC_REMAP
  1007. def_bool y
  1008. depends on X86_32 && NUMA
  1009. config ARCH_HAVE_MEMORY_PRESENT
  1010. def_bool y
  1011. depends on X86_32 && DISCONTIGMEM
  1012. config NEED_NODE_MEMMAP_SIZE
  1013. def_bool y
  1014. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1015. config ARCH_FLATMEM_ENABLE
  1016. def_bool y
  1017. depends on X86_32 && !NUMA
  1018. config ARCH_DISCONTIGMEM_ENABLE
  1019. def_bool y
  1020. depends on NUMA && X86_32
  1021. config ARCH_DISCONTIGMEM_DEFAULT
  1022. def_bool y
  1023. depends on NUMA && X86_32
  1024. config ARCH_SPARSEMEM_ENABLE
  1025. def_bool y
  1026. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1027. select SPARSEMEM_STATIC if X86_32
  1028. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1029. config ARCH_SPARSEMEM_DEFAULT
  1030. def_bool y
  1031. depends on X86_64
  1032. config ARCH_SELECT_MEMORY_MODEL
  1033. def_bool y
  1034. depends on ARCH_SPARSEMEM_ENABLE
  1035. config ARCH_MEMORY_PROBE
  1036. def_bool X86_64
  1037. depends on MEMORY_HOTPLUG
  1038. config ARCH_PROC_KCORE_TEXT
  1039. def_bool y
  1040. depends on X86_64 && PROC_KCORE
  1041. config ILLEGAL_POINTER_VALUE
  1042. hex
  1043. default 0 if X86_32
  1044. default 0xdead000000000000 if X86_64
  1045. source "mm/Kconfig"
  1046. config HIGHPTE
  1047. bool "Allocate 3rd-level pagetables from highmem"
  1048. depends on HIGHMEM
  1049. ---help---
  1050. The VM uses one page table entry for each page of physical memory.
  1051. For systems with a lot of RAM, this can be wasteful of precious
  1052. low memory. Setting this option will put user-space page table
  1053. entries in high memory.
  1054. config X86_CHECK_BIOS_CORRUPTION
  1055. bool "Check for low memory corruption"
  1056. ---help---
  1057. Periodically check for memory corruption in low memory, which
  1058. is suspected to be caused by BIOS. Even when enabled in the
  1059. configuration, it is disabled at runtime. Enable it by
  1060. setting "memory_corruption_check=1" on the kernel command
  1061. line. By default it scans the low 64k of memory every 60
  1062. seconds; see the memory_corruption_check_size and
  1063. memory_corruption_check_period parameters in
  1064. Documentation/kernel-parameters.txt to adjust this.
  1065. When enabled with the default parameters, this option has
  1066. almost no overhead, as it reserves a relatively small amount
  1067. of memory and scans it infrequently. It both detects corruption
  1068. and prevents it from affecting the running system.
  1069. It is, however, intended as a diagnostic tool; if repeatable
  1070. BIOS-originated corruption always affects the same memory,
  1071. you can use memmap= to prevent the kernel from using that
  1072. memory.
  1073. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1074. bool "Set the default setting of memory_corruption_check"
  1075. depends on X86_CHECK_BIOS_CORRUPTION
  1076. default y
  1077. ---help---
  1078. Set whether the default state of memory_corruption_check is
  1079. on or off.
  1080. config X86_RESERVE_LOW
  1081. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1082. default 64
  1083. range 4 640
  1084. ---help---
  1085. Specify the amount of low memory to reserve for the BIOS.
  1086. The first page contains BIOS data structures that the kernel
  1087. must not use, so that page must always be reserved.
  1088. By default we reserve the first 64K of physical RAM, as a
  1089. number of BIOSes are known to corrupt that memory range
  1090. during events such as suspend/resume or monitor cable
  1091. insertion, so it must not be used by the kernel.
  1092. You can set this to 4 if you are absolutely sure that you
  1093. trust the BIOS to get all its memory reservations and usages
  1094. right. If you know your BIOS have problems beyond the
  1095. default 64K area, you can set this to 640 to avoid using the
  1096. entire low memory range.
  1097. If you have doubts about the BIOS (e.g. suspend/resume does
  1098. not work or there's kernel crashes after certain hardware
  1099. hotplug events) then you might want to enable
  1100. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1101. typical corruption patterns.
  1102. Leave this to the default value of 64 if you are unsure.
  1103. config MATH_EMULATION
  1104. bool
  1105. prompt "Math emulation" if X86_32
  1106. ---help---
  1107. Linux can emulate a math coprocessor (used for floating point
  1108. operations) if you don't have one. 486DX and Pentium processors have
  1109. a math coprocessor built in, 486SX and 386 do not, unless you added
  1110. a 487DX or 387, respectively. (The messages during boot time can
  1111. give you some hints here ["man dmesg"].) Everyone needs either a
  1112. coprocessor or this emulation.
  1113. If you don't have a math coprocessor, you need to say Y here; if you
  1114. say Y here even though you have a coprocessor, the coprocessor will
  1115. be used nevertheless. (This behavior can be changed with the kernel
  1116. command line option "no387", which comes handy if your coprocessor
  1117. is broken. Try "man bootparam" or see the documentation of your boot
  1118. loader (lilo or loadlin) about how to pass options to the kernel at
  1119. boot time.) This means that it is a good idea to say Y here if you
  1120. intend to use this kernel on different machines.
  1121. More information about the internals of the Linux math coprocessor
  1122. emulation can be found in <file:arch/x86/math-emu/README>.
  1123. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1124. kernel, it won't hurt.
  1125. config MTRR
  1126. def_bool y
  1127. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1128. ---help---
  1129. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1130. the Memory Type Range Registers (MTRRs) may be used to control
  1131. processor access to memory ranges. This is most useful if you have
  1132. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1133. allows bus write transfers to be combined into a larger transfer
  1134. before bursting over the PCI/AGP bus. This can increase performance
  1135. of image write operations 2.5 times or more. Saying Y here creates a
  1136. /proc/mtrr file which may be used to manipulate your processor's
  1137. MTRRs. Typically the X server should use this.
  1138. This code has a reasonably generic interface so that similar
  1139. control registers on other processors can be easily supported
  1140. as well:
  1141. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1142. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1143. these, the ARRs are used to emulate the MTRRs.
  1144. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1145. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1146. write-combining. All of these processors are supported by this code
  1147. and it makes sense to say Y here if you have one of them.
  1148. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1149. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1150. can lead to all sorts of problems, so it's good to say Y here.
  1151. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1152. just add about 9 KB to your kernel.
  1153. See <file:Documentation/x86/mtrr.txt> for more information.
  1154. config MTRR_SANITIZER
  1155. def_bool y
  1156. prompt "MTRR cleanup support"
  1157. depends on MTRR
  1158. ---help---
  1159. Convert MTRR layout from continuous to discrete, so X drivers can
  1160. add writeback entries.
  1161. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1162. The largest mtrr entry size for a continuous block can be set with
  1163. mtrr_chunk_size.
  1164. If unsure, say Y.
  1165. config MTRR_SANITIZER_ENABLE_DEFAULT
  1166. int "MTRR cleanup enable value (0-1)"
  1167. range 0 1
  1168. default "0"
  1169. depends on MTRR_SANITIZER
  1170. ---help---
  1171. Enable mtrr cleanup default value
  1172. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1173. int "MTRR cleanup spare reg num (0-7)"
  1174. range 0 7
  1175. default "1"
  1176. depends on MTRR_SANITIZER
  1177. ---help---
  1178. mtrr cleanup spare entries default, it can be changed via
  1179. mtrr_spare_reg_nr=N on the kernel command line.
  1180. config X86_PAT
  1181. def_bool y
  1182. prompt "x86 PAT support" if EXPERT
  1183. depends on MTRR
  1184. ---help---
  1185. Use PAT attributes to setup page level cache control.
  1186. PATs are the modern equivalents of MTRRs and are much more
  1187. flexible than MTRRs.
  1188. Say N here if you see bootup problems (boot crash, boot hang,
  1189. spontaneous reboots) or a non-working video driver.
  1190. If unsure, say Y.
  1191. config ARCH_USES_PG_UNCACHED
  1192. def_bool y
  1193. depends on X86_PAT
  1194. config EFI
  1195. bool "EFI runtime service support"
  1196. depends on ACPI
  1197. ---help---
  1198. This enables the kernel to use EFI runtime services that are
  1199. available (such as the EFI variable services).
  1200. This option is only useful on systems that have EFI firmware.
  1201. In addition, you should use the latest ELILO loader available
  1202. at <http://elilo.sourceforge.net> in order to take advantage
  1203. of EFI runtime services. However, even with this option, the
  1204. resultant kernel should continue to boot on existing non-EFI
  1205. platforms.
  1206. config SECCOMP
  1207. def_bool y
  1208. prompt "Enable seccomp to safely compute untrusted bytecode"
  1209. ---help---
  1210. This kernel feature is useful for number crunching applications
  1211. that may need to compute untrusted bytecode during their
  1212. execution. By using pipes or other transports made available to
  1213. the process as file descriptors supporting the read/write
  1214. syscalls, it's possible to isolate those applications in
  1215. their own address space using seccomp. Once seccomp is
  1216. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1217. and the task is only allowed to execute a few safe syscalls
  1218. defined by each seccomp mode.
  1219. If unsure, say Y. Only embedded should say N here.
  1220. config CC_STACKPROTECTOR
  1221. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1222. ---help---
  1223. This option turns on the -fstack-protector GCC feature. This
  1224. feature puts, at the beginning of functions, a canary value on
  1225. the stack just before the return address, and validates
  1226. the value just before actually returning. Stack based buffer
  1227. overflows (that need to overwrite this return address) now also
  1228. overwrite the canary, which gets detected and the attack is then
  1229. neutralized via a kernel panic.
  1230. This feature requires gcc version 4.2 or above, or a distribution
  1231. gcc with the feature backported. Older versions are automatically
  1232. detected and for those versions, this configuration option is
  1233. ignored. (and a warning is printed during bootup)
  1234. source kernel/Kconfig.hz
  1235. config KEXEC
  1236. bool "kexec system call"
  1237. ---help---
  1238. kexec is a system call that implements the ability to shutdown your
  1239. current kernel, and to start another kernel. It is like a reboot
  1240. but it is independent of the system firmware. And like a reboot
  1241. you can start any kernel with it, not just Linux.
  1242. The name comes from the similarity to the exec system call.
  1243. It is an ongoing process to be certain the hardware in a machine
  1244. is properly shutdown, so do not be surprised if this code does not
  1245. initially work for you. It may help to enable device hotplugging
  1246. support. As of this writing the exact hardware interface is
  1247. strongly in flux, so no good recommendation can be made.
  1248. config CRASH_DUMP
  1249. bool "kernel crash dumps"
  1250. depends on X86_64 || (X86_32 && HIGHMEM)
  1251. ---help---
  1252. Generate crash dump after being started by kexec.
  1253. This should be normally only set in special crash dump kernels
  1254. which are loaded in the main kernel with kexec-tools into
  1255. a specially reserved region and then later executed after
  1256. a crash by kdump/kexec. The crash dump kernel must be compiled
  1257. to a memory address not used by the main kernel or BIOS using
  1258. PHYSICAL_START, or it must be built as a relocatable image
  1259. (CONFIG_RELOCATABLE=y).
  1260. For more details see Documentation/kdump/kdump.txt
  1261. config KEXEC_JUMP
  1262. bool "kexec jump (EXPERIMENTAL)"
  1263. depends on EXPERIMENTAL
  1264. depends on KEXEC && HIBERNATION
  1265. ---help---
  1266. Jump between original kernel and kexeced kernel and invoke
  1267. code in physical address mode via KEXEC
  1268. config PHYSICAL_START
  1269. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1270. default "0x1000000"
  1271. ---help---
  1272. This gives the physical address where the kernel is loaded.
  1273. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1274. bzImage will decompress itself to above physical address and
  1275. run from there. Otherwise, bzImage will run from the address where
  1276. it has been loaded by the boot loader and will ignore above physical
  1277. address.
  1278. In normal kdump cases one does not have to set/change this option
  1279. as now bzImage can be compiled as a completely relocatable image
  1280. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1281. address. This option is mainly useful for the folks who don't want
  1282. to use a bzImage for capturing the crash dump and want to use a
  1283. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1284. to be specifically compiled to run from a specific memory area
  1285. (normally a reserved region) and this option comes handy.
  1286. So if you are using bzImage for capturing the crash dump,
  1287. leave the value here unchanged to 0x1000000 and set
  1288. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1289. for capturing the crash dump change this value to start of
  1290. the reserved region. In other words, it can be set based on
  1291. the "X" value as specified in the "crashkernel=YM@XM"
  1292. command line boot parameter passed to the panic-ed
  1293. kernel. Please take a look at Documentation/kdump/kdump.txt
  1294. for more details about crash dumps.
  1295. Usage of bzImage for capturing the crash dump is recommended as
  1296. one does not have to build two kernels. Same kernel can be used
  1297. as production kernel and capture kernel. Above option should have
  1298. gone away after relocatable bzImage support is introduced. But it
  1299. is present because there are users out there who continue to use
  1300. vmlinux for dump capture. This option should go away down the
  1301. line.
  1302. Don't change this unless you know what you are doing.
  1303. config RELOCATABLE
  1304. bool "Build a relocatable kernel"
  1305. default y
  1306. ---help---
  1307. This builds a kernel image that retains relocation information
  1308. so it can be loaded someplace besides the default 1MB.
  1309. The relocations tend to make the kernel binary about 10% larger,
  1310. but are discarded at runtime.
  1311. One use is for the kexec on panic case where the recovery kernel
  1312. must live at a different physical address than the primary
  1313. kernel.
  1314. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1315. it has been loaded at and the compile time physical address
  1316. (CONFIG_PHYSICAL_START) is ignored.
  1317. # Relocation on x86-32 needs some additional build support
  1318. config X86_NEED_RELOCS
  1319. def_bool y
  1320. depends on X86_32 && RELOCATABLE
  1321. config PHYSICAL_ALIGN
  1322. hex "Alignment value to which kernel should be aligned" if X86_32
  1323. default "0x1000000"
  1324. range 0x2000 0x1000000
  1325. ---help---
  1326. This value puts the alignment restrictions on physical address
  1327. where kernel is loaded and run from. Kernel is compiled for an
  1328. address which meets above alignment restriction.
  1329. If bootloader loads the kernel at a non-aligned address and
  1330. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1331. address aligned to above value and run from there.
  1332. If bootloader loads the kernel at a non-aligned address and
  1333. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1334. load address and decompress itself to the address it has been
  1335. compiled for and run from there. The address for which kernel is
  1336. compiled already meets above alignment restrictions. Hence the
  1337. end result is that kernel runs from a physical address meeting
  1338. above alignment restrictions.
  1339. Don't change this unless you know what you are doing.
  1340. config HOTPLUG_CPU
  1341. bool "Support for hot-pluggable CPUs"
  1342. depends on SMP && HOTPLUG
  1343. ---help---
  1344. Say Y here to allow turning CPUs off and on. CPUs can be
  1345. controlled through /sys/devices/system/cpu.
  1346. ( Note: power management support will enable this option
  1347. automatically on SMP systems. )
  1348. Say N if you want to disable CPU hotplug.
  1349. config COMPAT_VDSO
  1350. def_bool y
  1351. prompt "Compat VDSO support"
  1352. depends on X86_32 || IA32_EMULATION
  1353. ---help---
  1354. Map the 32-bit VDSO to the predictable old-style address too.
  1355. Say N here if you are running a sufficiently recent glibc
  1356. version (2.3.3 or later), to remove the high-mapped
  1357. VDSO mapping and to exclusively use the randomized VDSO.
  1358. If unsure, say Y.
  1359. config CMDLINE_BOOL
  1360. bool "Built-in kernel command line"
  1361. ---help---
  1362. Allow for specifying boot arguments to the kernel at
  1363. build time. On some systems (e.g. embedded ones), it is
  1364. necessary or convenient to provide some or all of the
  1365. kernel boot arguments with the kernel itself (that is,
  1366. to not rely on the boot loader to provide them.)
  1367. To compile command line arguments into the kernel,
  1368. set this option to 'Y', then fill in the
  1369. the boot arguments in CONFIG_CMDLINE.
  1370. Systems with fully functional boot loaders (i.e. non-embedded)
  1371. should leave this option set to 'N'.
  1372. config CMDLINE
  1373. string "Built-in kernel command string"
  1374. depends on CMDLINE_BOOL
  1375. default ""
  1376. ---help---
  1377. Enter arguments here that should be compiled into the kernel
  1378. image and used at boot time. If the boot loader provides a
  1379. command line at boot time, it is appended to this string to
  1380. form the full kernel command line, when the system boots.
  1381. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1382. change this behavior.
  1383. In most cases, the command line (whether built-in or provided
  1384. by the boot loader) should specify the device for the root
  1385. file system.
  1386. config CMDLINE_OVERRIDE
  1387. bool "Built-in command line overrides boot loader arguments"
  1388. depends on CMDLINE_BOOL
  1389. ---help---
  1390. Set this option to 'Y' to have the kernel ignore the boot loader
  1391. command line, and use ONLY the built-in command line.
  1392. This is used to work around broken boot loaders. This should
  1393. be set to 'N' under normal conditions.
  1394. endmenu
  1395. config ARCH_ENABLE_MEMORY_HOTPLUG
  1396. def_bool y
  1397. depends on X86_64 || (X86_32 && HIGHMEM)
  1398. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1399. def_bool y
  1400. depends on MEMORY_HOTPLUG
  1401. config USE_PERCPU_NUMA_NODE_ID
  1402. def_bool y
  1403. depends on NUMA
  1404. menu "Power management and ACPI options"
  1405. config ARCH_HIBERNATION_HEADER
  1406. def_bool y
  1407. depends on X86_64 && HIBERNATION
  1408. source "kernel/power/Kconfig"
  1409. source "drivers/acpi/Kconfig"
  1410. source "drivers/sfi/Kconfig"
  1411. config X86_APM_BOOT
  1412. def_bool y
  1413. depends on APM || APM_MODULE
  1414. menuconfig APM
  1415. tristate "APM (Advanced Power Management) BIOS support"
  1416. depends on X86_32 && PM_SLEEP
  1417. ---help---
  1418. APM is a BIOS specification for saving power using several different
  1419. techniques. This is mostly useful for battery powered laptops with
  1420. APM compliant BIOSes. If you say Y here, the system time will be
  1421. reset after a RESUME operation, the /proc/apm device will provide
  1422. battery status information, and user-space programs will receive
  1423. notification of APM "events" (e.g. battery status change).
  1424. If you select "Y" here, you can disable actual use of the APM
  1425. BIOS by passing the "apm=off" option to the kernel at boot time.
  1426. Note that the APM support is almost completely disabled for
  1427. machines with more than one CPU.
  1428. In order to use APM, you will need supporting software. For location
  1429. and more information, read <file:Documentation/power/pm.txt> and the
  1430. Battery Powered Linux mini-HOWTO, available from
  1431. <http://www.tldp.org/docs.html#howto>.
  1432. This driver does not spin down disk drives (see the hdparm(8)
  1433. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1434. VESA-compliant "green" monitors.
  1435. This driver does not support the TI 4000M TravelMate and the ACER
  1436. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1437. desktop machines also don't have compliant BIOSes, and this driver
  1438. may cause those machines to panic during the boot phase.
  1439. Generally, if you don't have a battery in your machine, there isn't
  1440. much point in using this driver and you should say N. If you get
  1441. random kernel OOPSes or reboots that don't seem to be related to
  1442. anything, try disabling/enabling this option (or disabling/enabling
  1443. APM in your BIOS).
  1444. Some other things you should try when experiencing seemingly random,
  1445. "weird" problems:
  1446. 1) make sure that you have enough swap space and that it is
  1447. enabled.
  1448. 2) pass the "no-hlt" option to the kernel
  1449. 3) switch on floating point emulation in the kernel and pass
  1450. the "no387" option to the kernel
  1451. 4) pass the "floppy=nodma" option to the kernel
  1452. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1453. all but the first 4 MB of RAM)
  1454. 6) make sure that the CPU is not over clocked.
  1455. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1456. 8) disable the cache from your BIOS settings
  1457. 9) install a fan for the video card or exchange video RAM
  1458. 10) install a better fan for the CPU
  1459. 11) exchange RAM chips
  1460. 12) exchange the motherboard.
  1461. To compile this driver as a module, choose M here: the
  1462. module will be called apm.
  1463. if APM
  1464. config APM_IGNORE_USER_SUSPEND
  1465. bool "Ignore USER SUSPEND"
  1466. ---help---
  1467. This option will ignore USER SUSPEND requests. On machines with a
  1468. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1469. series notebooks, it is necessary to say Y because of a BIOS bug.
  1470. config APM_DO_ENABLE
  1471. bool "Enable PM at boot time"
  1472. ---help---
  1473. Enable APM features at boot time. From page 36 of the APM BIOS
  1474. specification: "When disabled, the APM BIOS does not automatically
  1475. power manage devices, enter the Standby State, enter the Suspend
  1476. State, or take power saving steps in response to CPU Idle calls."
  1477. This driver will make CPU Idle calls when Linux is idle (unless this
  1478. feature is turned off -- see "Do CPU IDLE calls", below). This
  1479. should always save battery power, but more complicated APM features
  1480. will be dependent on your BIOS implementation. You may need to turn
  1481. this option off if your computer hangs at boot time when using APM
  1482. support, or if it beeps continuously instead of suspending. Turn
  1483. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1484. T400CDT. This is off by default since most machines do fine without
  1485. this feature.
  1486. config APM_CPU_IDLE
  1487. bool "Make CPU Idle calls when idle"
  1488. ---help---
  1489. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1490. On some machines, this can activate improved power savings, such as
  1491. a slowed CPU clock rate, when the machine is idle. These idle calls
  1492. are made after the idle loop has run for some length of time (e.g.,
  1493. 333 mS). On some machines, this will cause a hang at boot time or
  1494. whenever the CPU becomes idle. (On machines with more than one CPU,
  1495. this option does nothing.)
  1496. config APM_DISPLAY_BLANK
  1497. bool "Enable console blanking using APM"
  1498. ---help---
  1499. Enable console blanking using the APM. Some laptops can use this to
  1500. turn off the LCD backlight when the screen blanker of the Linux
  1501. virtual console blanks the screen. Note that this is only used by
  1502. the virtual console screen blanker, and won't turn off the backlight
  1503. when using the X Window system. This also doesn't have anything to
  1504. do with your VESA-compliant power-saving monitor. Further, this
  1505. option doesn't work for all laptops -- it might not turn off your
  1506. backlight at all, or it might print a lot of errors to the console,
  1507. especially if you are using gpm.
  1508. config APM_ALLOW_INTS
  1509. bool "Allow interrupts during APM BIOS calls"
  1510. ---help---
  1511. Normally we disable external interrupts while we are making calls to
  1512. the APM BIOS as a measure to lessen the effects of a badly behaving
  1513. BIOS implementation. The BIOS should reenable interrupts if it
  1514. needs to. Unfortunately, some BIOSes do not -- especially those in
  1515. many of the newer IBM Thinkpads. If you experience hangs when you
  1516. suspend, try setting this to Y. Otherwise, say N.
  1517. endif # APM
  1518. source "drivers/cpufreq/Kconfig"
  1519. source "drivers/cpuidle/Kconfig"
  1520. source "drivers/idle/Kconfig"
  1521. endmenu
  1522. menu "Bus options (PCI etc.)"
  1523. config PCI
  1524. bool "PCI support"
  1525. default y
  1526. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1527. ---help---
  1528. Find out whether you have a PCI motherboard. PCI is the name of a
  1529. bus system, i.e. the way the CPU talks to the other stuff inside
  1530. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1531. VESA. If you have PCI, say Y, otherwise N.
  1532. choice
  1533. prompt "PCI access mode"
  1534. depends on X86_32 && PCI
  1535. default PCI_GOANY
  1536. ---help---
  1537. On PCI systems, the BIOS can be used to detect the PCI devices and
  1538. determine their configuration. However, some old PCI motherboards
  1539. have BIOS bugs and may crash if this is done. Also, some embedded
  1540. PCI-based systems don't have any BIOS at all. Linux can also try to
  1541. detect the PCI hardware directly without using the BIOS.
  1542. With this option, you can specify how Linux should detect the
  1543. PCI devices. If you choose "BIOS", the BIOS will be used,
  1544. if you choose "Direct", the BIOS won't be used, and if you
  1545. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1546. If you choose "Any", the kernel will try MMCONFIG, then the
  1547. direct access method and falls back to the BIOS if that doesn't
  1548. work. If unsure, go with the default, which is "Any".
  1549. config PCI_GOBIOS
  1550. bool "BIOS"
  1551. config PCI_GOMMCONFIG
  1552. bool "MMConfig"
  1553. config PCI_GODIRECT
  1554. bool "Direct"
  1555. config PCI_GOOLPC
  1556. bool "OLPC XO-1"
  1557. depends on OLPC
  1558. config PCI_GOANY
  1559. bool "Any"
  1560. endchoice
  1561. config PCI_BIOS
  1562. def_bool y
  1563. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1564. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1565. config PCI_DIRECT
  1566. def_bool y
  1567. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1568. config PCI_MMCONFIG
  1569. def_bool y
  1570. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1571. config PCI_OLPC
  1572. def_bool y
  1573. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1574. config PCI_XEN
  1575. def_bool y
  1576. depends on PCI && XEN
  1577. select SWIOTLB_XEN
  1578. config PCI_DOMAINS
  1579. def_bool y
  1580. depends on PCI
  1581. config PCI_MMCONFIG
  1582. bool "Support mmconfig PCI config space access"
  1583. depends on X86_64 && PCI && ACPI
  1584. config PCI_CNB20LE_QUIRK
  1585. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1586. default n
  1587. depends on PCI && EXPERIMENTAL
  1588. help
  1589. Read the PCI windows out of the CNB20LE host bridge. This allows
  1590. PCI hotplug to work on systems with the CNB20LE chipset which do
  1591. not have ACPI.
  1592. There's no public spec for this chipset, and this functionality
  1593. is known to be incomplete.
  1594. You should say N unless you know you need this.
  1595. source "drivers/pci/pcie/Kconfig"
  1596. source "drivers/pci/Kconfig"
  1597. # x86_64 have no ISA slots, but can have ISA-style DMA.
  1598. config ISA_DMA_API
  1599. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  1600. default y
  1601. help
  1602. Enables ISA-style DMA support for devices requiring such controllers.
  1603. If unsure, say Y.
  1604. if X86_32
  1605. config ISA
  1606. bool "ISA support"
  1607. ---help---
  1608. Find out whether you have ISA slots on your motherboard. ISA is the
  1609. name of a bus system, i.e. the way the CPU talks to the other stuff
  1610. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1611. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1612. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1613. config EISA
  1614. bool "EISA support"
  1615. depends on ISA
  1616. ---help---
  1617. The Extended Industry Standard Architecture (EISA) bus was
  1618. developed as an open alternative to the IBM MicroChannel bus.
  1619. The EISA bus provided some of the features of the IBM MicroChannel
  1620. bus while maintaining backward compatibility with cards made for
  1621. the older ISA bus. The EISA bus saw limited use between 1988 and
  1622. 1995 when it was made obsolete by the PCI bus.
  1623. Say Y here if you are building a kernel for an EISA-based machine.
  1624. Otherwise, say N.
  1625. source "drivers/eisa/Kconfig"
  1626. config MCA
  1627. bool "MCA support"
  1628. ---help---
  1629. MicroChannel Architecture is found in some IBM PS/2 machines and
  1630. laptops. It is a bus system similar to PCI or ISA. See
  1631. <file:Documentation/mca.txt> (and especially the web page given
  1632. there) before attempting to build an MCA bus kernel.
  1633. source "drivers/mca/Kconfig"
  1634. config SCx200
  1635. tristate "NatSemi SCx200 support"
  1636. ---help---
  1637. This provides basic support for National Semiconductor's
  1638. (now AMD's) Geode processors. The driver probes for the
  1639. PCI-IDs of several on-chip devices, so its a good dependency
  1640. for other scx200_* drivers.
  1641. If compiled as a module, the driver is named scx200.
  1642. config SCx200HR_TIMER
  1643. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1644. depends on SCx200
  1645. default y
  1646. ---help---
  1647. This driver provides a clocksource built upon the on-chip
  1648. 27MHz high-resolution timer. Its also a workaround for
  1649. NSC Geode SC-1100's buggy TSC, which loses time when the
  1650. processor goes idle (as is done by the scheduler). The
  1651. other workaround is idle=poll boot option.
  1652. config OLPC
  1653. bool "One Laptop Per Child support"
  1654. depends on !X86_PAE
  1655. select GPIOLIB
  1656. select OF
  1657. select OF_PROMTREE
  1658. ---help---
  1659. Add support for detecting the unique features of the OLPC
  1660. XO hardware.
  1661. config OLPC_XO1
  1662. tristate "OLPC XO-1 support"
  1663. depends on OLPC && MFD_CS5535
  1664. ---help---
  1665. Add support for non-essential features of the OLPC XO-1 laptop.
  1666. endif # X86_32
  1667. config AMD_NB
  1668. def_bool y
  1669. depends on CPU_SUP_AMD && PCI
  1670. source "drivers/pcmcia/Kconfig"
  1671. source "drivers/pci/hotplug/Kconfig"
  1672. config RAPIDIO
  1673. bool "RapidIO support"
  1674. depends on PCI
  1675. default n
  1676. help
  1677. If you say Y here, the kernel will include drivers and
  1678. infrastructure code to support RapidIO interconnect devices.
  1679. source "drivers/rapidio/Kconfig"
  1680. endmenu
  1681. menu "Executable file formats / Emulations"
  1682. source "fs/Kconfig.binfmt"
  1683. config IA32_EMULATION
  1684. bool "IA32 Emulation"
  1685. depends on X86_64
  1686. select COMPAT_BINFMT_ELF
  1687. ---help---
  1688. Include code to run 32-bit programs under a 64-bit kernel. You should
  1689. likely turn this on, unless you're 100% sure that you don't have any
  1690. 32-bit programs left.
  1691. config IA32_AOUT
  1692. tristate "IA32 a.out support"
  1693. depends on IA32_EMULATION
  1694. ---help---
  1695. Support old a.out binaries in the 32bit emulation.
  1696. config COMPAT
  1697. def_bool y
  1698. depends on IA32_EMULATION
  1699. config COMPAT_FOR_U64_ALIGNMENT
  1700. def_bool COMPAT
  1701. depends on X86_64
  1702. config SYSVIPC_COMPAT
  1703. def_bool y
  1704. depends on COMPAT && SYSVIPC
  1705. config KEYS_COMPAT
  1706. bool
  1707. depends on COMPAT && KEYS
  1708. default y
  1709. endmenu
  1710. config HAVE_ATOMIC_IOMAP
  1711. def_bool y
  1712. depends on X86_32
  1713. config HAVE_TEXT_POKE_SMP
  1714. bool
  1715. select STOP_MACHINE if SMP
  1716. source "net/Kconfig"
  1717. source "drivers/Kconfig"
  1718. source "drivers/firmware/Kconfig"
  1719. source "fs/Kconfig"
  1720. source "arch/x86/Kconfig.debug"
  1721. source "security/Kconfig"
  1722. source "crypto/Kconfig"
  1723. source "arch/x86/kvm/Kconfig"
  1724. source "lib/Kconfig"