Kconfig 55 KB

12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394959697989910010110210310410510610710810911011111211311411511611711811912012112212312412512612712812913013113213313413513613713813914014114214314414514614714814915015115215315415515615715815916016116216316416516616716816917017117217317417517617717817918018118218318418518618718818919019119219319419519619719819920020120220320420520620720820921021121221321421521621721821922022122222322422522622722822923023123223323423523623723823924024124224324424524624724824925025125225325425525625725825926026126226326426526626726826927027127227327427527627727827928028128228328428528628728828929029129229329429529629729829930030130230330430530630730830931031131231331431531631731831932032132232332432532632732832933033133233333433533633733833934034134234334434534634734834935035135235335435535635735835936036136236336436536636736836937037137237337437537637737837938038138238338438538638738838939039139239339439539639739839940040140240340440540640740840941041141241341441541641741841942042142242342442542642742842943043143243343443543643743843944044144244344444544644744844945045145245345445545645745845946046146246346446546646746846947047147247347447547647747847948048148248348448548648748848949049149249349449549649749849950050150250350450550650750850951051151251351451551651751851952052152252352452552652752852953053153253353453553653753853954054154254354454554654754854955055155255355455555655755855956056156256356456556656756856957057157257357457557657757857958058158258358458558658758858959059159259359459559659759859960060160260360460560660760860961061161261361461561661761861962062162262362462562662762862963063163263363463563663763863964064164264364464564664764864965065165265365465565665765865966066166266366466566666766866967067167267367467567667767867968068168268368468568668768868969069169269369469569669769869970070170270370470570670770870971071171271371471571671771871972072172272372472572672772872973073173273373473573673773873974074174274374474574674774874975075175275375475575675775875976076176276376476576676776876977077177277377477577677777877978078178278378478578678778878979079179279379479579679779879980080180280380480580680780880981081181281381481581681781881982082182282382482582682782882983083183283383483583683783883984084184284384484584684784884985085185285385485585685785885986086186286386486586686786886987087187287387487587687787887988088188288388488588688788888989089189289389489589689789889990090190290390490590690790890991091191291391491591691791891992092192292392492592692792892993093193293393493593693793893994094194294394494594694794894995095195295395495595695795895996096196296396496596696796896997097197297397497597697797897998098198298398498598698798898999099199299399499599699799899910001001100210031004100510061007100810091010101110121013101410151016101710181019102010211022102310241025102610271028102910301031103210331034103510361037103810391040104110421043104410451046104710481049105010511052105310541055105610571058105910601061106210631064106510661067106810691070107110721073107410751076107710781079108010811082108310841085108610871088108910901091109210931094109510961097109810991100110111021103110411051106110711081109111011111112111311141115111611171118111911201121112211231124112511261127112811291130113111321133113411351136113711381139114011411142114311441145114611471148114911501151115211531154115511561157115811591160116111621163116411651166116711681169117011711172117311741175117611771178117911801181118211831184118511861187118811891190119111921193119411951196119711981199120012011202120312041205120612071208120912101211121212131214121512161217121812191220122112221223122412251226122712281229123012311232123312341235123612371238123912401241124212431244124512461247124812491250125112521253125412551256125712581259126012611262126312641265126612671268126912701271127212731274127512761277127812791280128112821283128412851286128712881289129012911292129312941295129612971298129913001301130213031304130513061307130813091310131113121313131413151316131713181319132013211322132313241325132613271328132913301331133213331334133513361337133813391340134113421343134413451346134713481349135013511352135313541355135613571358135913601361136213631364136513661367136813691370137113721373137413751376137713781379138013811382138313841385138613871388138913901391139213931394139513961397139813991400140114021403140414051406140714081409141014111412141314141415141614171418141914201421142214231424142514261427142814291430143114321433143414351436143714381439144014411442144314441445144614471448144914501451145214531454145514561457145814591460146114621463146414651466146714681469147014711472147314741475147614771478147914801481148214831484148514861487148814891490149114921493149414951496149714981499150015011502150315041505150615071508150915101511151215131514151515161517151815191520152115221523152415251526152715281529153015311532153315341535153615371538153915401541154215431544154515461547154815491550155115521553155415551556155715581559156015611562156315641565156615671568156915701571157215731574157515761577157815791580158115821583158415851586158715881589159015911592159315941595159615971598159916001601160216031604160516061607160816091610161116121613161416151616161716181619162016211622162316241625162616271628162916301631163216331634163516361637163816391640164116421643164416451646164716481649165016511652165316541655165616571658165916601661166216631664166516661667166816691670167116721673167416751676167716781679168016811682168316841685168616871688168916901691169216931694169516961697169816991700170117021703170417051706170717081709171017111712171317141715171617171718171917201721172217231724172517261727172817291730
  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_UNSTABLE_SCHED_CLOCK
  18. select HAVE_IDE
  19. select HAVE_OPROFILE
  20. select HAVE_KPROBES
  21. select HAVE_KRETPROBES
  22. select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
  23. select HAVE_ARCH_KGDB if !X86_VOYAGER
  24. config ARCH_DEFCONFIG
  25. string
  26. default "arch/x86/configs/i386_defconfig" if X86_32
  27. default "arch/x86/configs/x86_64_defconfig" if X86_64
  28. config GENERIC_LOCKBREAK
  29. def_bool n
  30. config GENERIC_TIME
  31. def_bool y
  32. config GENERIC_CMOS_UPDATE
  33. def_bool y
  34. config CLOCKSOURCE_WATCHDOG
  35. def_bool y
  36. config GENERIC_CLOCKEVENTS
  37. def_bool y
  38. config GENERIC_CLOCKEVENTS_BROADCAST
  39. def_bool y
  40. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  41. config LOCKDEP_SUPPORT
  42. def_bool y
  43. config STACKTRACE_SUPPORT
  44. def_bool y
  45. config HAVE_LATENCYTOP_SUPPORT
  46. def_bool y
  47. config FAST_CMPXCHG_LOCAL
  48. bool
  49. default y
  50. config MMU
  51. def_bool y
  52. config ZONE_DMA
  53. def_bool y
  54. config SBUS
  55. bool
  56. config GENERIC_ISA_DMA
  57. def_bool y
  58. config GENERIC_IOMAP
  59. def_bool y
  60. config GENERIC_BUG
  61. def_bool y
  62. depends on BUG
  63. config GENERIC_HWEIGHT
  64. def_bool y
  65. config GENERIC_GPIO
  66. def_bool n
  67. config ARCH_MAY_HAVE_PC_FDC
  68. def_bool y
  69. config RWSEM_GENERIC_SPINLOCK
  70. def_bool !X86_XADD
  71. config RWSEM_XCHGADD_ALGORITHM
  72. def_bool X86_XADD
  73. config ARCH_HAS_ILOG2_U32
  74. def_bool n
  75. config ARCH_HAS_ILOG2_U64
  76. def_bool n
  77. config ARCH_HAS_CPU_IDLE_WAIT
  78. def_bool y
  79. config GENERIC_CALIBRATE_DELAY
  80. def_bool y
  81. config GENERIC_TIME_VSYSCALL
  82. bool
  83. default X86_64
  84. config ARCH_HAS_CPU_RELAX
  85. def_bool y
  86. config ARCH_HAS_CACHE_LINE_SIZE
  87. def_bool y
  88. config HAVE_SETUP_PER_CPU_AREA
  89. def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
  90. config HAVE_CPUMASK_OF_CPU_MAP
  91. def_bool X86_64_SMP
  92. config ARCH_HIBERNATION_POSSIBLE
  93. def_bool y
  94. depends on !SMP || !X86_VOYAGER
  95. config ARCH_SUSPEND_POSSIBLE
  96. def_bool y
  97. depends on !X86_VOYAGER
  98. config ZONE_DMA32
  99. bool
  100. default X86_64
  101. config ARCH_POPULATES_NODE_MAP
  102. def_bool y
  103. config AUDIT_ARCH
  104. bool
  105. default X86_64
  106. config ARCH_SUPPORTS_AOUT
  107. def_bool y
  108. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  109. def_bool y
  110. # Use the generic interrupt handling code in kernel/irq/:
  111. config GENERIC_HARDIRQS
  112. bool
  113. default y
  114. config GENERIC_IRQ_PROBE
  115. bool
  116. default y
  117. config GENERIC_PENDING_IRQ
  118. bool
  119. depends on GENERIC_HARDIRQS && SMP
  120. default y
  121. config X86_SMP
  122. bool
  123. depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
  124. default y
  125. config X86_32_SMP
  126. def_bool y
  127. depends on X86_32 && SMP
  128. config X86_64_SMP
  129. def_bool y
  130. depends on X86_64 && SMP
  131. config X86_HT
  132. bool
  133. depends on SMP
  134. depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
  135. default y
  136. config X86_BIOS_REBOOT
  137. bool
  138. depends on !X86_VISWS && !X86_VOYAGER
  139. default y
  140. config X86_TRAMPOLINE
  141. bool
  142. depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
  143. default y
  144. config KTIME_SCALAR
  145. def_bool X86_32
  146. source "init/Kconfig"
  147. menu "Processor type and features"
  148. source "kernel/time/Kconfig"
  149. config SMP
  150. bool "Symmetric multi-processing support"
  151. ---help---
  152. This enables support for systems with more than one CPU. If you have
  153. a system with only one CPU, like most personal computers, say N. If
  154. you have a system with more than one CPU, say Y.
  155. If you say N here, the kernel will run on single and multiprocessor
  156. machines, but will use only one CPU of a multiprocessor machine. If
  157. you say Y here, the kernel will run on many, but not all,
  158. singleprocessor machines. On a singleprocessor machine, the kernel
  159. will run faster if you say N here.
  160. Note that if you say Y here and choose architecture "586" or
  161. "Pentium" under "Processor family", the kernel will not work on 486
  162. architectures. Similarly, multiprocessor kernels for the "PPro"
  163. architecture may not work on all Pentium based boards.
  164. People using multiprocessor machines who say Y here should also say
  165. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  166. Management" code will be disabled if you say Y here.
  167. See also <file:Documentation/i386/IO-APIC.txt>,
  168. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  169. <http://www.tldp.org/docs.html#howto>.
  170. If you don't know what to do here, say N.
  171. choice
  172. prompt "Subarchitecture Type"
  173. default X86_PC
  174. config X86_PC
  175. bool "PC-compatible"
  176. help
  177. Choose this option if your computer is a standard PC or compatible.
  178. config X86_ELAN
  179. bool "AMD Elan"
  180. depends on X86_32
  181. help
  182. Select this for an AMD Elan processor.
  183. Do not use this option for K6/Athlon/Opteron processors!
  184. If unsure, choose "PC-compatible" instead.
  185. config X86_VOYAGER
  186. bool "Voyager (NCR)"
  187. depends on X86_32 && (SMP || BROKEN)
  188. help
  189. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  190. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  191. *** WARNING ***
  192. If you do not specifically know you have a Voyager based machine,
  193. say N here, otherwise the kernel you build will not be bootable.
  194. config X86_NUMAQ
  195. bool "NUMAQ (IBM/Sequent)"
  196. depends on SMP && X86_32
  197. select NUMA
  198. help
  199. This option is used for getting Linux to run on a (IBM/Sequent) NUMA
  200. multiquad box. This changes the way that processors are bootstrapped,
  201. and uses Clustered Logical APIC addressing mode instead of Flat Logical.
  202. You will need a new lynxer.elf file to flash your firmware with - send
  203. email to <Martin.Bligh@us.ibm.com>.
  204. config X86_SUMMIT
  205. bool "Summit/EXA (IBM x440)"
  206. depends on X86_32 && SMP
  207. help
  208. This option is needed for IBM systems that use the Summit/EXA chipset.
  209. In particular, it is needed for the x440.
  210. If you don't have one of these computers, you should say N here.
  211. If you want to build a NUMA kernel, you must select ACPI.
  212. config X86_BIGSMP
  213. bool "Support for other sub-arch SMP systems with more than 8 CPUs"
  214. depends on X86_32 && SMP
  215. help
  216. This option is needed for the systems that have more than 8 CPUs
  217. and if the system is not of any sub-arch type above.
  218. If you don't have such a system, you should say N here.
  219. config X86_VISWS
  220. bool "SGI 320/540 (Visual Workstation)"
  221. depends on X86_32
  222. help
  223. The SGI Visual Workstation series is an IA32-based workstation
  224. based on SGI systems chips with some legacy PC hardware attached.
  225. Say Y here to create a kernel to run on the SGI 320 or 540.
  226. A kernel compiled for the Visual Workstation will not run on PCs
  227. and vice versa. See <file:Documentation/sgi-visws.txt> for details.
  228. config X86_GENERICARCH
  229. bool "Generic architecture (Summit, bigsmp, ES7000, default)"
  230. depends on X86_32
  231. help
  232. This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
  233. It is intended for a generic binary kernel.
  234. If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
  235. config X86_ES7000
  236. bool "Support for Unisys ES7000 IA32 series"
  237. depends on X86_32 && SMP
  238. help
  239. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  240. supposed to run on an IA32-based Unisys ES7000 system.
  241. Only choose this option if you have such a system, otherwise you
  242. should say N here.
  243. config X86_RDC321X
  244. bool "RDC R-321x SoC"
  245. depends on X86_32
  246. select M486
  247. select X86_REBOOTFIXUPS
  248. select GENERIC_GPIO
  249. select LEDS_CLASS
  250. select LEDS_GPIO
  251. select NEW_LEDS
  252. help
  253. This option is needed for RDC R-321x system-on-chip, also known
  254. as R-8610-(G).
  255. If you don't have one of these chips, you should say N here.
  256. config X86_VSMP
  257. bool "Support for ScaleMP vSMP"
  258. select PARAVIRT
  259. depends on X86_64
  260. help
  261. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  262. supposed to run on these EM64T-based machines. Only choose this option
  263. if you have one of these machines.
  264. endchoice
  265. config SCHED_NO_NO_OMIT_FRAME_POINTER
  266. def_bool y
  267. prompt "Single-depth WCHAN output"
  268. depends on X86_32
  269. help
  270. Calculate simpler /proc/<PID>/wchan values. If this option
  271. is disabled then wchan values will recurse back to the
  272. caller function. This provides more accurate wchan values,
  273. at the expense of slightly more scheduling overhead.
  274. If in doubt, say "Y".
  275. menuconfig PARAVIRT_GUEST
  276. bool "Paravirtualized guest support"
  277. help
  278. Say Y here to get to see options related to running Linux under
  279. various hypervisors. This option alone does not add any kernel code.
  280. If you say N, all options in this submenu will be skipped and disabled.
  281. if PARAVIRT_GUEST
  282. source "arch/x86/xen/Kconfig"
  283. config VMI
  284. bool "VMI Guest support"
  285. select PARAVIRT
  286. depends on X86_32
  287. depends on !(X86_VISWS || X86_VOYAGER)
  288. help
  289. VMI provides a paravirtualized interface to the VMware ESX server
  290. (it could be used by other hypervisors in theory too, but is not
  291. at the moment), by linking the kernel to a GPL-ed ROM module
  292. provided by the hypervisor.
  293. config KVM_CLOCK
  294. bool "KVM paravirtualized clock"
  295. select PARAVIRT
  296. depends on !(X86_VISWS || X86_VOYAGER)
  297. help
  298. Turning on this option will allow you to run a paravirtualized clock
  299. when running over the KVM hypervisor. Instead of relying on a PIT
  300. (or probably other) emulation by the underlying device model, the host
  301. provides the guest with timing infrastructure such as time of day, and
  302. system time
  303. config KVM_GUEST
  304. bool "KVM Guest support"
  305. select PARAVIRT
  306. depends on !(X86_VISWS || X86_VOYAGER)
  307. help
  308. This option enables various optimizations for running under the KVM
  309. hypervisor.
  310. source "arch/x86/lguest/Kconfig"
  311. config PARAVIRT
  312. bool "Enable paravirtualization code"
  313. depends on !(X86_VISWS || X86_VOYAGER)
  314. help
  315. This changes the kernel so it can modify itself when it is run
  316. under a hypervisor, potentially improving performance significantly
  317. over full virtualization. However, when run without a hypervisor
  318. the kernel is theoretically slower and slightly larger.
  319. config PARAVIRT_CLOCK
  320. bool
  321. default n
  322. endif
  323. config MEMTEST_BOOTPARAM
  324. bool "Memtest boot parameter"
  325. depends on X86_64
  326. default y
  327. help
  328. This option adds a kernel parameter 'memtest', which allows memtest
  329. to be disabled at boot. If this option is selected, memtest
  330. functionality can be disabled with memtest=0 on the kernel
  331. command line. The purpose of this option is to allow a single
  332. kernel image to be distributed with memtest built in, but not
  333. necessarily enabled.
  334. If you are unsure how to answer this question, answer Y.
  335. config MEMTEST_BOOTPARAM_VALUE
  336. int "Memtest boot parameter default value (0-4)"
  337. depends on MEMTEST_BOOTPARAM
  338. range 0 4
  339. default 0
  340. help
  341. This option sets the default value for the kernel parameter
  342. 'memtest', which allows memtest to be disabled at boot. If this
  343. option is set to 0 (zero), the memtest kernel parameter will
  344. default to 0, disabling memtest at bootup. If this option is
  345. set to 4, the memtest kernel parameter will default to 4,
  346. enabling memtest at bootup, and use that as pattern number.
  347. If you are unsure how to answer this question, answer 0.
  348. config ACPI_SRAT
  349. def_bool y
  350. depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  351. select ACPI_NUMA
  352. config HAVE_ARCH_PARSE_SRAT
  353. def_bool y
  354. depends on ACPI_SRAT
  355. config X86_SUMMIT_NUMA
  356. def_bool y
  357. depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  358. config X86_CYCLONE_TIMER
  359. def_bool y
  360. depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
  361. config ES7000_CLUSTERED_APIC
  362. def_bool y
  363. depends on SMP && X86_ES7000 && MPENTIUMIII
  364. source "arch/x86/Kconfig.cpu"
  365. config HPET_TIMER
  366. def_bool X86_64
  367. prompt "HPET Timer Support" if X86_32
  368. help
  369. Use the IA-PC HPET (High Precision Event Timer) to manage
  370. time in preference to the PIT and RTC, if a HPET is
  371. present.
  372. HPET is the next generation timer replacing legacy 8254s.
  373. The HPET provides a stable time base on SMP
  374. systems, unlike the TSC, but it is more expensive to access,
  375. as it is off-chip. You can find the HPET spec at
  376. <http://www.intel.com/hardwaredesign/hpetspec.htm>.
  377. You can safely choose Y here. However, HPET will only be
  378. activated if the platform and the BIOS support this feature.
  379. Otherwise the 8254 will be used for timing services.
  380. Choose N to continue using the legacy 8254 timer.
  381. config HPET_EMULATE_RTC
  382. def_bool y
  383. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  384. # Mark as embedded because too many people got it wrong.
  385. # The code disables itself when not needed.
  386. config DMI
  387. default y
  388. bool "Enable DMI scanning" if EMBEDDED
  389. help
  390. Enabled scanning of DMI to identify machine quirks. Say Y
  391. here unless you have verified that your setup is not
  392. affected by entries in the DMI blacklist. Required by PNP
  393. BIOS code.
  394. config GART_IOMMU
  395. bool "GART IOMMU support" if EMBEDDED
  396. default y
  397. select SWIOTLB
  398. select AGP
  399. depends on X86_64 && PCI
  400. help
  401. Support for full DMA access of devices with 32bit memory access only
  402. on systems with more than 3GB. This is usually needed for USB,
  403. sound, many IDE/SATA chipsets and some other devices.
  404. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  405. based hardware IOMMU and a software bounce buffer based IOMMU used
  406. on Intel systems and as fallback.
  407. The code is only active when needed (enough memory and limited
  408. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  409. too.
  410. config CALGARY_IOMMU
  411. bool "IBM Calgary IOMMU support"
  412. select SWIOTLB
  413. depends on X86_64 && PCI && EXPERIMENTAL
  414. help
  415. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  416. systems. Needed to run systems with more than 3GB of memory
  417. properly with 32-bit PCI devices that do not support DAC
  418. (Double Address Cycle). Calgary also supports bus level
  419. isolation, where all DMAs pass through the IOMMU. This
  420. prevents them from going anywhere except their intended
  421. destination. This catches hard-to-find kernel bugs and
  422. mis-behaving drivers and devices that do not use the DMA-API
  423. properly to set up their DMA buffers. The IOMMU can be
  424. turned off at boot time with the iommu=off parameter.
  425. Normally the kernel will make the right choice by itself.
  426. If unsure, say Y.
  427. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  428. def_bool y
  429. prompt "Should Calgary be enabled by default?"
  430. depends on CALGARY_IOMMU
  431. help
  432. Should Calgary be enabled by default? if you choose 'y', Calgary
  433. will be used (if it exists). If you choose 'n', Calgary will not be
  434. used even if it exists. If you choose 'n' and would like to use
  435. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  436. If unsure, say Y.
  437. # need this always selected by IOMMU for the VIA workaround
  438. config SWIOTLB
  439. bool
  440. help
  441. Support for software bounce buffers used on x86-64 systems
  442. which don't have a hardware IOMMU (e.g. the current generation
  443. of Intel's x86-64 CPUs). Using this PCI devices which can only
  444. access 32-bits of memory can be used on systems with more than
  445. 3 GB of memory. If unsure, say Y.
  446. config IOMMU_HELPER
  447. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
  448. config NR_CPUS
  449. int "Maximum number of CPUs (2-255)"
  450. range 2 255
  451. depends on SMP
  452. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  453. default "8"
  454. help
  455. This allows you to specify the maximum number of CPUs which this
  456. kernel will support. The maximum supported value is 255 and the
  457. minimum value which makes sense is 2.
  458. This is purely to save memory - each supported CPU adds
  459. approximately eight kilobytes to the kernel image.
  460. config SCHED_SMT
  461. bool "SMT (Hyperthreading) scheduler support"
  462. depends on X86_HT
  463. help
  464. SMT scheduler support improves the CPU scheduler's decision making
  465. when dealing with Intel Pentium 4 chips with HyperThreading at a
  466. cost of slightly increased overhead in some places. If unsure say
  467. N here.
  468. config SCHED_MC
  469. def_bool y
  470. prompt "Multi-core scheduler support"
  471. depends on X86_HT
  472. help
  473. Multi-core scheduler support improves the CPU scheduler's decision
  474. making when dealing with multi-core CPU chips at a cost of slightly
  475. increased overhead in some places. If unsure say N here.
  476. source "kernel/Kconfig.preempt"
  477. config X86_UP_APIC
  478. bool "Local APIC support on uniprocessors"
  479. depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
  480. help
  481. A local APIC (Advanced Programmable Interrupt Controller) is an
  482. integrated interrupt controller in the CPU. If you have a single-CPU
  483. system which has a processor with a local APIC, you can say Y here to
  484. enable and use it. If you say Y here even though your machine doesn't
  485. have a local APIC, then the kernel will still run with no slowdown at
  486. all. The local APIC supports CPU-generated self-interrupts (timer,
  487. performance counters), and the NMI watchdog which detects hard
  488. lockups.
  489. config X86_UP_IOAPIC
  490. bool "IO-APIC support on uniprocessors"
  491. depends on X86_UP_APIC
  492. help
  493. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  494. SMP-capable replacement for PC-style interrupt controllers. Most
  495. SMP systems and many recent uniprocessor systems have one.
  496. If you have a single-CPU system with an IO-APIC, you can say Y here
  497. to use it. If you say Y here even though your machine doesn't have
  498. an IO-APIC, then the kernel will still run with no slowdown at all.
  499. config X86_LOCAL_APIC
  500. def_bool y
  501. depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
  502. config X86_IO_APIC
  503. def_bool y
  504. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
  505. config X86_VISWS_APIC
  506. def_bool y
  507. depends on X86_32 && X86_VISWS
  508. config X86_MCE
  509. bool "Machine Check Exception"
  510. depends on !X86_VOYAGER
  511. ---help---
  512. Machine Check Exception support allows the processor to notify the
  513. kernel if it detects a problem (e.g. overheating, component failure).
  514. The action the kernel takes depends on the severity of the problem,
  515. ranging from a warning message on the console, to halting the machine.
  516. Your processor must be a Pentium or newer to support this - check the
  517. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  518. have a design flaw which leads to false MCE events - hence MCE is
  519. disabled on all P5 processors, unless explicitly enabled with "mce"
  520. as a boot argument. Similarly, if MCE is built in and creates a
  521. problem on some new non-standard machine, you can boot with "nomce"
  522. to disable it. MCE support simply ignores non-MCE processors like
  523. the 386 and 486, so nearly everyone can say Y here.
  524. config X86_MCE_INTEL
  525. def_bool y
  526. prompt "Intel MCE features"
  527. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  528. help
  529. Additional support for intel specific MCE features such as
  530. the thermal monitor.
  531. config X86_MCE_AMD
  532. def_bool y
  533. prompt "AMD MCE features"
  534. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  535. help
  536. Additional support for AMD specific MCE features such as
  537. the DRAM Error Threshold.
  538. config X86_MCE_NONFATAL
  539. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  540. depends on X86_32 && X86_MCE
  541. help
  542. Enabling this feature starts a timer that triggers every 5 seconds which
  543. will look at the machine check registers to see if anything happened.
  544. Non-fatal problems automatically get corrected (but still logged).
  545. Disable this if you don't want to see these messages.
  546. Seeing the messages this option prints out may be indicative of dying
  547. or out-of-spec (ie, overclocked) hardware.
  548. This option only does something on certain CPUs.
  549. (AMD Athlon/Duron and Intel Pentium 4)
  550. config X86_MCE_P4THERMAL
  551. bool "check for P4 thermal throttling interrupt."
  552. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
  553. help
  554. Enabling this feature will cause a message to be printed when the P4
  555. enters thermal throttling.
  556. config VM86
  557. bool "Enable VM86 support" if EMBEDDED
  558. default y
  559. depends on X86_32
  560. help
  561. This option is required by programs like DOSEMU to run 16-bit legacy
  562. code on X86 processors. It also may be needed by software like
  563. XFree86 to initialize some video cards via BIOS. Disabling this
  564. option saves about 6k.
  565. config TOSHIBA
  566. tristate "Toshiba Laptop support"
  567. depends on X86_32
  568. ---help---
  569. This adds a driver to safely access the System Management Mode of
  570. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  571. not work on models with a Phoenix BIOS. The System Management Mode
  572. is used to set the BIOS and power saving options on Toshiba portables.
  573. For information on utilities to make use of this driver see the
  574. Toshiba Linux utilities web site at:
  575. <http://www.buzzard.org.uk/toshiba/>.
  576. Say Y if you intend to run this kernel on a Toshiba portable.
  577. Say N otherwise.
  578. config I8K
  579. tristate "Dell laptop support"
  580. ---help---
  581. This adds a driver to safely access the System Management Mode
  582. of the CPU on the Dell Inspiron 8000. The System Management Mode
  583. is used to read cpu temperature and cooling fan status and to
  584. control the fans on the I8K portables.
  585. This driver has been tested only on the Inspiron 8000 but it may
  586. also work with other Dell laptops. You can force loading on other
  587. models by passing the parameter `force=1' to the module. Use at
  588. your own risk.
  589. For information on utilities to make use of this driver see the
  590. I8K Linux utilities web site at:
  591. <http://people.debian.org/~dz/i8k/>
  592. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  593. Say N otherwise.
  594. config X86_REBOOTFIXUPS
  595. def_bool n
  596. prompt "Enable X86 board specific fixups for reboot"
  597. depends on X86_32 && X86
  598. ---help---
  599. This enables chipset and/or board specific fixups to be done
  600. in order to get reboot to work correctly. This is only needed on
  601. some combinations of hardware and BIOS. The symptom, for which
  602. this config is intended, is when reboot ends with a stalled/hung
  603. system.
  604. Currently, the only fixup is for the Geode machines using
  605. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  606. Say Y if you want to enable the fixup. Currently, it's safe to
  607. enable this option even if you don't need it.
  608. Say N otherwise.
  609. config MICROCODE
  610. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  611. select FW_LOADER
  612. ---help---
  613. If you say Y here, you will be able to update the microcode on
  614. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  615. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  616. actual microcode binary data itself which is not shipped with the
  617. Linux kernel.
  618. For latest news and information on obtaining all the required
  619. ingredients for this driver, check:
  620. <http://www.urbanmyth.org/microcode/>.
  621. To compile this driver as a module, choose M here: the
  622. module will be called microcode.
  623. config MICROCODE_OLD_INTERFACE
  624. def_bool y
  625. depends on MICROCODE
  626. config X86_MSR
  627. tristate "/dev/cpu/*/msr - Model-specific register support"
  628. help
  629. This device gives privileged processes access to the x86
  630. Model-Specific Registers (MSRs). It is a character device with
  631. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  632. MSR accesses are directed to a specific CPU on multi-processor
  633. systems.
  634. config X86_CPUID
  635. tristate "/dev/cpu/*/cpuid - CPU information support"
  636. help
  637. This device gives processes access to the x86 CPUID instruction to
  638. be executed on a specific processor. It is a character device
  639. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  640. /dev/cpu/31/cpuid.
  641. choice
  642. prompt "High Memory Support"
  643. default HIGHMEM4G if !X86_NUMAQ
  644. default HIGHMEM64G if X86_NUMAQ
  645. depends on X86_32
  646. config NOHIGHMEM
  647. bool "off"
  648. depends on !X86_NUMAQ
  649. ---help---
  650. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  651. However, the address space of 32-bit x86 processors is only 4
  652. Gigabytes large. That means that, if you have a large amount of
  653. physical memory, not all of it can be "permanently mapped" by the
  654. kernel. The physical memory that's not permanently mapped is called
  655. "high memory".
  656. If you are compiling a kernel which will never run on a machine with
  657. more than 1 Gigabyte total physical RAM, answer "off" here (default
  658. choice and suitable for most users). This will result in a "3GB/1GB"
  659. split: 3GB are mapped so that each process sees a 3GB virtual memory
  660. space and the remaining part of the 4GB virtual memory space is used
  661. by the kernel to permanently map as much physical memory as
  662. possible.
  663. If the machine has between 1 and 4 Gigabytes physical RAM, then
  664. answer "4GB" here.
  665. If more than 4 Gigabytes is used then answer "64GB" here. This
  666. selection turns Intel PAE (Physical Address Extension) mode on.
  667. PAE implements 3-level paging on IA32 processors. PAE is fully
  668. supported by Linux, PAE mode is implemented on all recent Intel
  669. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  670. then the kernel will not boot on CPUs that don't support PAE!
  671. The actual amount of total physical memory will either be
  672. auto detected or can be forced by using a kernel command line option
  673. such as "mem=256M". (Try "man bootparam" or see the documentation of
  674. your boot loader (lilo or loadlin) about how to pass options to the
  675. kernel at boot time.)
  676. If unsure, say "off".
  677. config HIGHMEM4G
  678. bool "4GB"
  679. depends on !X86_NUMAQ
  680. help
  681. Select this if you have a 32-bit processor and between 1 and 4
  682. gigabytes of physical RAM.
  683. config HIGHMEM64G
  684. bool "64GB"
  685. depends on !M386 && !M486
  686. select X86_PAE
  687. help
  688. Select this if you have a 32-bit processor and more than 4
  689. gigabytes of physical RAM.
  690. endchoice
  691. choice
  692. depends on EXPERIMENTAL
  693. prompt "Memory split" if EMBEDDED
  694. default VMSPLIT_3G
  695. depends on X86_32
  696. help
  697. Select the desired split between kernel and user memory.
  698. If the address range available to the kernel is less than the
  699. physical memory installed, the remaining memory will be available
  700. as "high memory". Accessing high memory is a little more costly
  701. than low memory, as it needs to be mapped into the kernel first.
  702. Note that increasing the kernel address space limits the range
  703. available to user programs, making the address space there
  704. tighter. Selecting anything other than the default 3G/1G split
  705. will also likely make your kernel incompatible with binary-only
  706. kernel modules.
  707. If you are not absolutely sure what you are doing, leave this
  708. option alone!
  709. config VMSPLIT_3G
  710. bool "3G/1G user/kernel split"
  711. config VMSPLIT_3G_OPT
  712. depends on !X86_PAE
  713. bool "3G/1G user/kernel split (for full 1G low memory)"
  714. config VMSPLIT_2G
  715. bool "2G/2G user/kernel split"
  716. config VMSPLIT_2G_OPT
  717. depends on !X86_PAE
  718. bool "2G/2G user/kernel split (for full 2G low memory)"
  719. config VMSPLIT_1G
  720. bool "1G/3G user/kernel split"
  721. endchoice
  722. config PAGE_OFFSET
  723. hex
  724. default 0xB0000000 if VMSPLIT_3G_OPT
  725. default 0x80000000 if VMSPLIT_2G
  726. default 0x78000000 if VMSPLIT_2G_OPT
  727. default 0x40000000 if VMSPLIT_1G
  728. default 0xC0000000
  729. depends on X86_32
  730. config HIGHMEM
  731. def_bool y
  732. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  733. config X86_PAE
  734. def_bool n
  735. prompt "PAE (Physical Address Extension) Support"
  736. depends on X86_32 && !HIGHMEM4G
  737. select RESOURCES_64BIT
  738. help
  739. PAE is required for NX support, and furthermore enables
  740. larger swapspace support for non-overcommit purposes. It
  741. has the cost of more pagetable lookup overhead, and also
  742. consumes more pagetable space per process.
  743. # Common NUMA Features
  744. config NUMA
  745. bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
  746. depends on SMP
  747. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
  748. default n if X86_PC
  749. default y if (X86_NUMAQ || X86_SUMMIT)
  750. help
  751. Enable NUMA (Non Uniform Memory Access) support.
  752. The kernel will try to allocate memory used by a CPU on the
  753. local memory controller of the CPU and add some more
  754. NUMA awareness to the kernel.
  755. For i386 this is currently highly experimental and should be only
  756. used for kernel development. It might also cause boot failures.
  757. For x86_64 this is recommended on all multiprocessor Opteron systems.
  758. If the system is EM64T, you should say N unless your system is
  759. EM64T NUMA.
  760. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  761. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  762. config K8_NUMA
  763. def_bool y
  764. prompt "Old style AMD Opteron NUMA detection"
  765. depends on X86_64 && NUMA && PCI
  766. help
  767. Enable K8 NUMA node topology detection. You should say Y here if
  768. you have a multi processor AMD K8 system. This uses an old
  769. method to read the NUMA configuration directly from the builtin
  770. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  771. instead, which also takes priority if both are compiled in.
  772. config X86_64_ACPI_NUMA
  773. def_bool y
  774. prompt "ACPI NUMA detection"
  775. depends on X86_64 && NUMA && ACPI && PCI
  776. select ACPI_NUMA
  777. help
  778. Enable ACPI SRAT based node topology detection.
  779. # Some NUMA nodes have memory ranges that span
  780. # other nodes. Even though a pfn is valid and
  781. # between a node's start and end pfns, it may not
  782. # reside on that node. See memmap_init_zone()
  783. # for details.
  784. config NODES_SPAN_OTHER_NODES
  785. def_bool y
  786. depends on X86_64_ACPI_NUMA
  787. config NUMA_EMU
  788. bool "NUMA emulation"
  789. depends on X86_64 && NUMA
  790. help
  791. Enable NUMA emulation. A flat machine will be split
  792. into virtual nodes when booted with "numa=fake=N", where N is the
  793. number of nodes. This is only useful for debugging.
  794. config NODES_SHIFT
  795. int "Max num nodes shift(1-15)"
  796. range 1 15 if X86_64
  797. default "6" if X86_64
  798. default "4" if X86_NUMAQ
  799. default "3"
  800. depends on NEED_MULTIPLE_NODES
  801. config HAVE_ARCH_BOOTMEM_NODE
  802. def_bool y
  803. depends on X86_32 && NUMA
  804. config ARCH_HAVE_MEMORY_PRESENT
  805. def_bool y
  806. depends on X86_32 && DISCONTIGMEM
  807. config NEED_NODE_MEMMAP_SIZE
  808. def_bool y
  809. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  810. config HAVE_ARCH_ALLOC_REMAP
  811. def_bool y
  812. depends on X86_32 && NUMA
  813. config ARCH_FLATMEM_ENABLE
  814. def_bool y
  815. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
  816. config ARCH_DISCONTIGMEM_ENABLE
  817. def_bool y
  818. depends on NUMA && X86_32
  819. config ARCH_DISCONTIGMEM_DEFAULT
  820. def_bool y
  821. depends on NUMA && X86_32
  822. config ARCH_SPARSEMEM_DEFAULT
  823. def_bool y
  824. depends on X86_64
  825. config ARCH_SPARSEMEM_ENABLE
  826. def_bool y
  827. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
  828. select SPARSEMEM_STATIC if X86_32
  829. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  830. config ARCH_SELECT_MEMORY_MODEL
  831. def_bool y
  832. depends on ARCH_SPARSEMEM_ENABLE
  833. config ARCH_MEMORY_PROBE
  834. def_bool X86_64
  835. depends on MEMORY_HOTPLUG
  836. source "mm/Kconfig"
  837. config HIGHPTE
  838. bool "Allocate 3rd-level pagetables from highmem"
  839. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  840. help
  841. The VM uses one page table entry for each page of physical memory.
  842. For systems with a lot of RAM, this can be wasteful of precious
  843. low memory. Setting this option will put user-space page table
  844. entries in high memory.
  845. config MATH_EMULATION
  846. bool
  847. prompt "Math emulation" if X86_32
  848. ---help---
  849. Linux can emulate a math coprocessor (used for floating point
  850. operations) if you don't have one. 486DX and Pentium processors have
  851. a math coprocessor built in, 486SX and 386 do not, unless you added
  852. a 487DX or 387, respectively. (The messages during boot time can
  853. give you some hints here ["man dmesg"].) Everyone needs either a
  854. coprocessor or this emulation.
  855. If you don't have a math coprocessor, you need to say Y here; if you
  856. say Y here even though you have a coprocessor, the coprocessor will
  857. be used nevertheless. (This behavior can be changed with the kernel
  858. command line option "no387", which comes handy if your coprocessor
  859. is broken. Try "man bootparam" or see the documentation of your boot
  860. loader (lilo or loadlin) about how to pass options to the kernel at
  861. boot time.) This means that it is a good idea to say Y here if you
  862. intend to use this kernel on different machines.
  863. More information about the internals of the Linux math coprocessor
  864. emulation can be found in <file:arch/x86/math-emu/README>.
  865. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  866. kernel, it won't hurt.
  867. config MTRR
  868. bool "MTRR (Memory Type Range Register) support"
  869. ---help---
  870. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  871. the Memory Type Range Registers (MTRRs) may be used to control
  872. processor access to memory ranges. This is most useful if you have
  873. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  874. allows bus write transfers to be combined into a larger transfer
  875. before bursting over the PCI/AGP bus. This can increase performance
  876. of image write operations 2.5 times or more. Saying Y here creates a
  877. /proc/mtrr file which may be used to manipulate your processor's
  878. MTRRs. Typically the X server should use this.
  879. This code has a reasonably generic interface so that similar
  880. control registers on other processors can be easily supported
  881. as well:
  882. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  883. Registers (ARRs) which provide a similar functionality to MTRRs. For
  884. these, the ARRs are used to emulate the MTRRs.
  885. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  886. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  887. write-combining. All of these processors are supported by this code
  888. and it makes sense to say Y here if you have one of them.
  889. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  890. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  891. can lead to all sorts of problems, so it's good to say Y here.
  892. You can safely say Y even if your machine doesn't have MTRRs, you'll
  893. just add about 9 KB to your kernel.
  894. See <file:Documentation/mtrr.txt> for more information.
  895. config X86_PAT
  896. bool
  897. prompt "x86 PAT support"
  898. depends on MTRR
  899. help
  900. Use PAT attributes to setup page level cache control.
  901. PATs are the modern equivalents of MTRRs and are much more
  902. flexible than MTRRs.
  903. Say N here if you see bootup problems (boot crash, boot hang,
  904. spontaneous reboots) or a non-working video driver.
  905. If unsure, say Y.
  906. config EFI
  907. def_bool n
  908. prompt "EFI runtime service support"
  909. depends on ACPI
  910. ---help---
  911. This enables the kernel to use EFI runtime services that are
  912. available (such as the EFI variable services).
  913. This option is only useful on systems that have EFI firmware.
  914. In addition, you should use the latest ELILO loader available
  915. at <http://elilo.sourceforge.net> in order to take advantage
  916. of EFI runtime services. However, even with this option, the
  917. resultant kernel should continue to boot on existing non-EFI
  918. platforms.
  919. config IRQBALANCE
  920. def_bool y
  921. prompt "Enable kernel irq balancing"
  922. depends on X86_32 && SMP && X86_IO_APIC
  923. help
  924. The default yes will allow the kernel to do irq load balancing.
  925. Saying no will keep the kernel from doing irq load balancing.
  926. config SECCOMP
  927. def_bool y
  928. prompt "Enable seccomp to safely compute untrusted bytecode"
  929. depends on PROC_FS
  930. help
  931. This kernel feature is useful for number crunching applications
  932. that may need to compute untrusted bytecode during their
  933. execution. By using pipes or other transports made available to
  934. the process as file descriptors supporting the read/write
  935. syscalls, it's possible to isolate those applications in
  936. their own address space using seccomp. Once seccomp is
  937. enabled via /proc/<pid>/seccomp, it cannot be disabled
  938. and the task is only allowed to execute a few safe syscalls
  939. defined by each seccomp mode.
  940. If unsure, say Y. Only embedded should say N here.
  941. config CC_STACKPROTECTOR
  942. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  943. depends on X86_64 && EXPERIMENTAL && BROKEN
  944. help
  945. This option turns on the -fstack-protector GCC feature. This
  946. feature puts, at the beginning of critical functions, a canary
  947. value on the stack just before the return address, and validates
  948. the value just before actually returning. Stack based buffer
  949. overflows (that need to overwrite this return address) now also
  950. overwrite the canary, which gets detected and the attack is then
  951. neutralized via a kernel panic.
  952. This feature requires gcc version 4.2 or above, or a distribution
  953. gcc with the feature backported. Older versions are automatically
  954. detected and for those versions, this configuration option is ignored.
  955. config CC_STACKPROTECTOR_ALL
  956. bool "Use stack-protector for all functions"
  957. depends on CC_STACKPROTECTOR
  958. help
  959. Normally, GCC only inserts the canary value protection for
  960. functions that use large-ish on-stack buffers. By enabling
  961. this option, GCC will be asked to do this for ALL functions.
  962. source kernel/Kconfig.hz
  963. config KEXEC
  964. bool "kexec system call"
  965. depends on X86_BIOS_REBOOT
  966. help
  967. kexec is a system call that implements the ability to shutdown your
  968. current kernel, and to start another kernel. It is like a reboot
  969. but it is independent of the system firmware. And like a reboot
  970. you can start any kernel with it, not just Linux.
  971. The name comes from the similarity to the exec system call.
  972. It is an ongoing process to be certain the hardware in a machine
  973. is properly shutdown, so do not be surprised if this code does not
  974. initially work for you. It may help to enable device hotplugging
  975. support. As of this writing the exact hardware interface is
  976. strongly in flux, so no good recommendation can be made.
  977. config CRASH_DUMP
  978. bool "kernel crash dumps (EXPERIMENTAL)"
  979. depends on EXPERIMENTAL
  980. depends on X86_64 || (X86_32 && HIGHMEM)
  981. help
  982. Generate crash dump after being started by kexec.
  983. This should be normally only set in special crash dump kernels
  984. which are loaded in the main kernel with kexec-tools into
  985. a specially reserved region and then later executed after
  986. a crash by kdump/kexec. The crash dump kernel must be compiled
  987. to a memory address not used by the main kernel or BIOS using
  988. PHYSICAL_START, or it must be built as a relocatable image
  989. (CONFIG_RELOCATABLE=y).
  990. For more details see Documentation/kdump/kdump.txt
  991. config PHYSICAL_START
  992. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  993. default "0x1000000" if X86_NUMAQ
  994. default "0x200000" if X86_64
  995. default "0x100000"
  996. help
  997. This gives the physical address where the kernel is loaded.
  998. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  999. bzImage will decompress itself to above physical address and
  1000. run from there. Otherwise, bzImage will run from the address where
  1001. it has been loaded by the boot loader and will ignore above physical
  1002. address.
  1003. In normal kdump cases one does not have to set/change this option
  1004. as now bzImage can be compiled as a completely relocatable image
  1005. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1006. address. This option is mainly useful for the folks who don't want
  1007. to use a bzImage for capturing the crash dump and want to use a
  1008. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1009. to be specifically compiled to run from a specific memory area
  1010. (normally a reserved region) and this option comes handy.
  1011. So if you are using bzImage for capturing the crash dump, leave
  1012. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  1013. Otherwise if you plan to use vmlinux for capturing the crash dump
  1014. change this value to start of the reserved region (Typically 16MB
  1015. 0x1000000). In other words, it can be set based on the "X" value as
  1016. specified in the "crashkernel=YM@XM" command line boot parameter
  1017. passed to the panic-ed kernel. Typically this parameter is set as
  1018. crashkernel=64M@16M. Please take a look at
  1019. Documentation/kdump/kdump.txt for more details about crash dumps.
  1020. Usage of bzImage for capturing the crash dump is recommended as
  1021. one does not have to build two kernels. Same kernel can be used
  1022. as production kernel and capture kernel. Above option should have
  1023. gone away after relocatable bzImage support is introduced. But it
  1024. is present because there are users out there who continue to use
  1025. vmlinux for dump capture. This option should go away down the
  1026. line.
  1027. Don't change this unless you know what you are doing.
  1028. config RELOCATABLE
  1029. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1030. depends on EXPERIMENTAL
  1031. help
  1032. This builds a kernel image that retains relocation information
  1033. so it can be loaded someplace besides the default 1MB.
  1034. The relocations tend to make the kernel binary about 10% larger,
  1035. but are discarded at runtime.
  1036. One use is for the kexec on panic case where the recovery kernel
  1037. must live at a different physical address than the primary
  1038. kernel.
  1039. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1040. it has been loaded at and the compile time physical address
  1041. (CONFIG_PHYSICAL_START) is ignored.
  1042. config PHYSICAL_ALIGN
  1043. hex
  1044. prompt "Alignment value to which kernel should be aligned" if X86_32
  1045. default "0x100000" if X86_32
  1046. default "0x200000" if X86_64
  1047. range 0x2000 0x400000
  1048. help
  1049. This value puts the alignment restrictions on physical address
  1050. where kernel is loaded and run from. Kernel is compiled for an
  1051. address which meets above alignment restriction.
  1052. If bootloader loads the kernel at a non-aligned address and
  1053. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1054. address aligned to above value and run from there.
  1055. If bootloader loads the kernel at a non-aligned address and
  1056. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1057. load address and decompress itself to the address it has been
  1058. compiled for and run from there. The address for which kernel is
  1059. compiled already meets above alignment restrictions. Hence the
  1060. end result is that kernel runs from a physical address meeting
  1061. above alignment restrictions.
  1062. Don't change this unless you know what you are doing.
  1063. config HOTPLUG_CPU
  1064. bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
  1065. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  1066. ---help---
  1067. Say Y here to experiment with turning CPUs off and on, and to
  1068. enable suspend on SMP systems. CPUs can be controlled through
  1069. /sys/devices/system/cpu.
  1070. Say N if you want to disable CPU hotplug and don't need to
  1071. suspend.
  1072. config COMPAT_VDSO
  1073. def_bool y
  1074. prompt "Compat VDSO support"
  1075. depends on X86_32 || IA32_EMULATION
  1076. help
  1077. Map the 32-bit VDSO to the predictable old-style address too.
  1078. ---help---
  1079. Say N here if you are running a sufficiently recent glibc
  1080. version (2.3.3 or later), to remove the high-mapped
  1081. VDSO mapping and to exclusively use the randomized VDSO.
  1082. If unsure, say Y.
  1083. endmenu
  1084. config ARCH_ENABLE_MEMORY_HOTPLUG
  1085. def_bool y
  1086. depends on X86_64 || (X86_32 && HIGHMEM)
  1087. config HAVE_ARCH_EARLY_PFN_TO_NID
  1088. def_bool X86_64
  1089. depends on NUMA
  1090. menu "Power management options"
  1091. depends on !X86_VOYAGER
  1092. config ARCH_HIBERNATION_HEADER
  1093. def_bool y
  1094. depends on X86_64 && HIBERNATION
  1095. source "kernel/power/Kconfig"
  1096. source "drivers/acpi/Kconfig"
  1097. config X86_APM_BOOT
  1098. bool
  1099. default y
  1100. depends on APM || APM_MODULE
  1101. menuconfig APM
  1102. tristate "APM (Advanced Power Management) BIOS support"
  1103. depends on X86_32 && PM_SLEEP && !X86_VISWS
  1104. ---help---
  1105. APM is a BIOS specification for saving power using several different
  1106. techniques. This is mostly useful for battery powered laptops with
  1107. APM compliant BIOSes. If you say Y here, the system time will be
  1108. reset after a RESUME operation, the /proc/apm device will provide
  1109. battery status information, and user-space programs will receive
  1110. notification of APM "events" (e.g. battery status change).
  1111. If you select "Y" here, you can disable actual use of the APM
  1112. BIOS by passing the "apm=off" option to the kernel at boot time.
  1113. Note that the APM support is almost completely disabled for
  1114. machines with more than one CPU.
  1115. In order to use APM, you will need supporting software. For location
  1116. and more information, read <file:Documentation/power/pm.txt> and the
  1117. Battery Powered Linux mini-HOWTO, available from
  1118. <http://www.tldp.org/docs.html#howto>.
  1119. This driver does not spin down disk drives (see the hdparm(8)
  1120. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1121. VESA-compliant "green" monitors.
  1122. This driver does not support the TI 4000M TravelMate and the ACER
  1123. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1124. desktop machines also don't have compliant BIOSes, and this driver
  1125. may cause those machines to panic during the boot phase.
  1126. Generally, if you don't have a battery in your machine, there isn't
  1127. much point in using this driver and you should say N. If you get
  1128. random kernel OOPSes or reboots that don't seem to be related to
  1129. anything, try disabling/enabling this option (or disabling/enabling
  1130. APM in your BIOS).
  1131. Some other things you should try when experiencing seemingly random,
  1132. "weird" problems:
  1133. 1) make sure that you have enough swap space and that it is
  1134. enabled.
  1135. 2) pass the "no-hlt" option to the kernel
  1136. 3) switch on floating point emulation in the kernel and pass
  1137. the "no387" option to the kernel
  1138. 4) pass the "floppy=nodma" option to the kernel
  1139. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1140. all but the first 4 MB of RAM)
  1141. 6) make sure that the CPU is not over clocked.
  1142. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1143. 8) disable the cache from your BIOS settings
  1144. 9) install a fan for the video card or exchange video RAM
  1145. 10) install a better fan for the CPU
  1146. 11) exchange RAM chips
  1147. 12) exchange the motherboard.
  1148. To compile this driver as a module, choose M here: the
  1149. module will be called apm.
  1150. if APM
  1151. config APM_IGNORE_USER_SUSPEND
  1152. bool "Ignore USER SUSPEND"
  1153. help
  1154. This option will ignore USER SUSPEND requests. On machines with a
  1155. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1156. series notebooks, it is necessary to say Y because of a BIOS bug.
  1157. config APM_DO_ENABLE
  1158. bool "Enable PM at boot time"
  1159. ---help---
  1160. Enable APM features at boot time. From page 36 of the APM BIOS
  1161. specification: "When disabled, the APM BIOS does not automatically
  1162. power manage devices, enter the Standby State, enter the Suspend
  1163. State, or take power saving steps in response to CPU Idle calls."
  1164. This driver will make CPU Idle calls when Linux is idle (unless this
  1165. feature is turned off -- see "Do CPU IDLE calls", below). This
  1166. should always save battery power, but more complicated APM features
  1167. will be dependent on your BIOS implementation. You may need to turn
  1168. this option off if your computer hangs at boot time when using APM
  1169. support, or if it beeps continuously instead of suspending. Turn
  1170. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1171. T400CDT. This is off by default since most machines do fine without
  1172. this feature.
  1173. config APM_CPU_IDLE
  1174. bool "Make CPU Idle calls when idle"
  1175. help
  1176. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1177. On some machines, this can activate improved power savings, such as
  1178. a slowed CPU clock rate, when the machine is idle. These idle calls
  1179. are made after the idle loop has run for some length of time (e.g.,
  1180. 333 mS). On some machines, this will cause a hang at boot time or
  1181. whenever the CPU becomes idle. (On machines with more than one CPU,
  1182. this option does nothing.)
  1183. config APM_DISPLAY_BLANK
  1184. bool "Enable console blanking using APM"
  1185. help
  1186. Enable console blanking using the APM. Some laptops can use this to
  1187. turn off the LCD backlight when the screen blanker of the Linux
  1188. virtual console blanks the screen. Note that this is only used by
  1189. the virtual console screen blanker, and won't turn off the backlight
  1190. when using the X Window system. This also doesn't have anything to
  1191. do with your VESA-compliant power-saving monitor. Further, this
  1192. option doesn't work for all laptops -- it might not turn off your
  1193. backlight at all, or it might print a lot of errors to the console,
  1194. especially if you are using gpm.
  1195. config APM_ALLOW_INTS
  1196. bool "Allow interrupts during APM BIOS calls"
  1197. help
  1198. Normally we disable external interrupts while we are making calls to
  1199. the APM BIOS as a measure to lessen the effects of a badly behaving
  1200. BIOS implementation. The BIOS should reenable interrupts if it
  1201. needs to. Unfortunately, some BIOSes do not -- especially those in
  1202. many of the newer IBM Thinkpads. If you experience hangs when you
  1203. suspend, try setting this to Y. Otherwise, say N.
  1204. config APM_REAL_MODE_POWER_OFF
  1205. bool "Use real mode APM BIOS call to power off"
  1206. help
  1207. Use real mode APM BIOS calls to switch off the computer. This is
  1208. a work-around for a number of buggy BIOSes. Switch this option on if
  1209. your computer crashes instead of powering off properly.
  1210. endif # APM
  1211. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1212. source "drivers/cpuidle/Kconfig"
  1213. endmenu
  1214. menu "Bus options (PCI etc.)"
  1215. config PCI
  1216. bool "PCI support" if !X86_VISWS && !X86_VSMP
  1217. depends on !X86_VOYAGER
  1218. default y
  1219. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1220. help
  1221. Find out whether you have a PCI motherboard. PCI is the name of a
  1222. bus system, i.e. the way the CPU talks to the other stuff inside
  1223. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1224. VESA. If you have PCI, say Y, otherwise N.
  1225. choice
  1226. prompt "PCI access mode"
  1227. depends on X86_32 && PCI && !X86_VISWS
  1228. default PCI_GOANY
  1229. ---help---
  1230. On PCI systems, the BIOS can be used to detect the PCI devices and
  1231. determine their configuration. However, some old PCI motherboards
  1232. have BIOS bugs and may crash if this is done. Also, some embedded
  1233. PCI-based systems don't have any BIOS at all. Linux can also try to
  1234. detect the PCI hardware directly without using the BIOS.
  1235. With this option, you can specify how Linux should detect the
  1236. PCI devices. If you choose "BIOS", the BIOS will be used,
  1237. if you choose "Direct", the BIOS won't be used, and if you
  1238. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1239. If you choose "Any", the kernel will try MMCONFIG, then the
  1240. direct access method and falls back to the BIOS if that doesn't
  1241. work. If unsure, go with the default, which is "Any".
  1242. config PCI_GOBIOS
  1243. bool "BIOS"
  1244. config PCI_GOMMCONFIG
  1245. bool "MMConfig"
  1246. config PCI_GODIRECT
  1247. bool "Direct"
  1248. config PCI_GOOLPC
  1249. bool "OLPC"
  1250. depends on OLPC
  1251. config PCI_GOANY
  1252. bool "Any"
  1253. endchoice
  1254. config PCI_BIOS
  1255. def_bool y
  1256. depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
  1257. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1258. config PCI_DIRECT
  1259. def_bool y
  1260. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
  1261. config PCI_MMCONFIG
  1262. def_bool y
  1263. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1264. config PCI_OLPC
  1265. def_bool y
  1266. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1267. config PCI_DOMAINS
  1268. def_bool y
  1269. depends on PCI
  1270. config PCI_MMCONFIG
  1271. bool "Support mmconfig PCI config space access"
  1272. depends on X86_64 && PCI && ACPI
  1273. config DMAR
  1274. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1275. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1276. help
  1277. DMA remapping (DMAR) devices support enables independent address
  1278. translations for Direct Memory Access (DMA) from devices.
  1279. These DMA remapping devices are reported via ACPI tables
  1280. and include PCI device scope covered by these DMA
  1281. remapping devices.
  1282. config DMAR_GFX_WA
  1283. def_bool y
  1284. prompt "Support for Graphics workaround"
  1285. depends on DMAR
  1286. help
  1287. Current Graphics drivers tend to use physical address
  1288. for DMA and avoid using DMA APIs. Setting this config
  1289. option permits the IOMMU driver to set a unity map for
  1290. all the OS-visible memory. Hence the driver can continue
  1291. to use physical addresses for DMA.
  1292. config DMAR_FLOPPY_WA
  1293. def_bool y
  1294. depends on DMAR
  1295. help
  1296. Floppy disk drivers are know to bypass DMA API calls
  1297. thereby failing to work when IOMMU is enabled. This
  1298. workaround will setup a 1:1 mapping for the first
  1299. 16M to make floppy (an ISA device) work.
  1300. source "drivers/pci/pcie/Kconfig"
  1301. source "drivers/pci/Kconfig"
  1302. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1303. config ISA_DMA_API
  1304. def_bool y
  1305. if X86_32
  1306. config ISA
  1307. bool "ISA support"
  1308. depends on !(X86_VOYAGER || X86_VISWS)
  1309. help
  1310. Find out whether you have ISA slots on your motherboard. ISA is the
  1311. name of a bus system, i.e. the way the CPU talks to the other stuff
  1312. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1313. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1314. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1315. config EISA
  1316. bool "EISA support"
  1317. depends on ISA
  1318. ---help---
  1319. The Extended Industry Standard Architecture (EISA) bus was
  1320. developed as an open alternative to the IBM MicroChannel bus.
  1321. The EISA bus provided some of the features of the IBM MicroChannel
  1322. bus while maintaining backward compatibility with cards made for
  1323. the older ISA bus. The EISA bus saw limited use between 1988 and
  1324. 1995 when it was made obsolete by the PCI bus.
  1325. Say Y here if you are building a kernel for an EISA-based machine.
  1326. Otherwise, say N.
  1327. source "drivers/eisa/Kconfig"
  1328. config MCA
  1329. bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
  1330. default y if X86_VOYAGER
  1331. help
  1332. MicroChannel Architecture is found in some IBM PS/2 machines and
  1333. laptops. It is a bus system similar to PCI or ISA. See
  1334. <file:Documentation/mca.txt> (and especially the web page given
  1335. there) before attempting to build an MCA bus kernel.
  1336. source "drivers/mca/Kconfig"
  1337. config SCx200
  1338. tristate "NatSemi SCx200 support"
  1339. depends on !X86_VOYAGER
  1340. help
  1341. This provides basic support for National Semiconductor's
  1342. (now AMD's) Geode processors. The driver probes for the
  1343. PCI-IDs of several on-chip devices, so its a good dependency
  1344. for other scx200_* drivers.
  1345. If compiled as a module, the driver is named scx200.
  1346. config SCx200HR_TIMER
  1347. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1348. depends on SCx200 && GENERIC_TIME
  1349. default y
  1350. help
  1351. This driver provides a clocksource built upon the on-chip
  1352. 27MHz high-resolution timer. Its also a workaround for
  1353. NSC Geode SC-1100's buggy TSC, which loses time when the
  1354. processor goes idle (as is done by the scheduler). The
  1355. other workaround is idle=poll boot option.
  1356. config GEODE_MFGPT_TIMER
  1357. def_bool y
  1358. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1359. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1360. help
  1361. This driver provides a clock event source based on the MFGPT
  1362. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1363. MFGPTs have a better resolution and max interval than the
  1364. generic PIT, and are suitable for use as high-res timers.
  1365. config OLPC
  1366. bool "One Laptop Per Child support"
  1367. default n
  1368. help
  1369. Add support for detecting the unique features of the OLPC
  1370. XO hardware.
  1371. endif # X86_32
  1372. config K8_NB
  1373. def_bool y
  1374. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1375. source "drivers/pcmcia/Kconfig"
  1376. source "drivers/pci/hotplug/Kconfig"
  1377. endmenu
  1378. menu "Executable file formats / Emulations"
  1379. source "fs/Kconfig.binfmt"
  1380. config IA32_EMULATION
  1381. bool "IA32 Emulation"
  1382. depends on X86_64
  1383. select COMPAT_BINFMT_ELF
  1384. help
  1385. Include code to run 32-bit programs under a 64-bit kernel. You should
  1386. likely turn this on, unless you're 100% sure that you don't have any
  1387. 32-bit programs left.
  1388. config IA32_AOUT
  1389. tristate "IA32 a.out support"
  1390. depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
  1391. help
  1392. Support old a.out binaries in the 32bit emulation.
  1393. config COMPAT
  1394. def_bool y
  1395. depends on IA32_EMULATION
  1396. config COMPAT_FOR_U64_ALIGNMENT
  1397. def_bool COMPAT
  1398. depends on X86_64
  1399. config SYSVIPC_COMPAT
  1400. def_bool y
  1401. depends on X86_64 && COMPAT && SYSVIPC
  1402. endmenu
  1403. source "net/Kconfig"
  1404. source "drivers/Kconfig"
  1405. source "drivers/firmware/Kconfig"
  1406. source "fs/Kconfig"
  1407. source "arch/x86/Kconfig.debug"
  1408. source "security/Kconfig"
  1409. source "crypto/Kconfig"
  1410. source "arch/x86/kvm/Kconfig"
  1411. source "lib/Kconfig"