Kconfig 55 KB

12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394959697989910010110210310410510610710810911011111211311411511611711811912012112212312412512612712812913013113213313413513613713813914014114214314414514614714814915015115215315415515615715815916016116216316416516616716816917017117217317417517617717817918018118218318418518618718818919019119219319419519619719819920020120220320420520620720820921021121221321421521621721821922022122222322422522622722822923023123223323423523623723823924024124224324424524624724824925025125225325425525625725825926026126226326426526626726826927027127227327427527627727827928028128228328428528628728828929029129229329429529629729829930030130230330430530630730830931031131231331431531631731831932032132232332432532632732832933033133233333433533633733833934034134234334434534634734834935035135235335435535635735835936036136236336436536636736836937037137237337437537637737837938038138238338438538638738838939039139239339439539639739839940040140240340440540640740840941041141241341441541641741841942042142242342442542642742842943043143243343443543643743843944044144244344444544644744844945045145245345445545645745845946046146246346446546646746846947047147247347447547647747847948048148248348448548648748848949049149249349449549649749849950050150250350450550650750850951051151251351451551651751851952052152252352452552652752852953053153253353453553653753853954054154254354454554654754854955055155255355455555655755855956056156256356456556656756856957057157257357457557657757857958058158258358458558658758858959059159259359459559659759859960060160260360460560660760860961061161261361461561661761861962062162262362462562662762862963063163263363463563663763863964064164264364464564664764864965065165265365465565665765865966066166266366466566666766866967067167267367467567667767867968068168268368468568668768868969069169269369469569669769869970070170270370470570670770870971071171271371471571671771871972072172272372472572672772872973073173273373473573673773873974074174274374474574674774874975075175275375475575675775875976076176276376476576676776876977077177277377477577677777877978078178278378478578678778878979079179279379479579679779879980080180280380480580680780880981081181281381481581681781881982082182282382482582682782882983083183283383483583683783883984084184284384484584684784884985085185285385485585685785885986086186286386486586686786886987087187287387487587687787887988088188288388488588688788888989089189289389489589689789889990090190290390490590690790890991091191291391491591691791891992092192292392492592692792892993093193293393493593693793893994094194294394494594694794894995095195295395495595695795895996096196296396496596696796896997097197297397497597697797897998098198298398498598698798898999099199299399499599699799899910001001100210031004100510061007100810091010101110121013101410151016101710181019102010211022102310241025102610271028102910301031103210331034103510361037103810391040104110421043104410451046104710481049105010511052105310541055105610571058105910601061106210631064106510661067106810691070107110721073107410751076107710781079108010811082108310841085108610871088108910901091109210931094109510961097109810991100110111021103110411051106110711081109111011111112111311141115111611171118111911201121112211231124112511261127112811291130113111321133113411351136113711381139114011411142114311441145114611471148114911501151115211531154115511561157115811591160116111621163116411651166116711681169117011711172117311741175117611771178117911801181118211831184118511861187118811891190119111921193119411951196119711981199120012011202120312041205120612071208120912101211121212131214121512161217121812191220122112221223122412251226122712281229123012311232123312341235123612371238123912401241124212431244124512461247124812491250125112521253125412551256125712581259126012611262126312641265126612671268126912701271127212731274127512761277127812791280128112821283128412851286128712881289129012911292129312941295129612971298129913001301130213031304130513061307130813091310131113121313131413151316131713181319132013211322132313241325132613271328132913301331133213331334133513361337133813391340134113421343134413451346134713481349135013511352135313541355135613571358135913601361136213631364136513661367136813691370137113721373137413751376137713781379138013811382138313841385138613871388138913901391139213931394139513961397139813991400140114021403140414051406140714081409141014111412141314141415141614171418141914201421142214231424142514261427142814291430143114321433143414351436143714381439144014411442144314441445144614471448144914501451145214531454145514561457145814591460146114621463146414651466146714681469147014711472147314741475147614771478147914801481148214831484148514861487148814891490149114921493149414951496149714981499150015011502150315041505150615071508150915101511151215131514151515161517151815191520152115221523152415251526152715281529153015311532153315341535153615371538153915401541154215431544154515461547154815491550155115521553155415551556155715581559156015611562156315641565156615671568156915701571157215731574157515761577157815791580158115821583158415851586158715881589159015911592159315941595159615971598159916001601160216031604160516061607160816091610161116121613161416151616161716181619162016211622162316241625162616271628162916301631163216331634163516361637163816391640164116421643164416451646164716481649165016511652165316541655165616571658165916601661166216631664166516661667166816691670167116721673167416751676167716781679168016811682168316841685168616871688168916901691169216931694169516961697169816991700170117021703170417051706170717081709171017111712171317141715171617171718171917201721172217231724172517261727172817291730173117321733
  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 DEFCONFIG_LIST
  25. string
  26. depends on X86_32
  27. option defconfig_list
  28. default "arch/x86/configs/i386_defconfig"
  29. config DEFCONFIG_LIST
  30. string
  31. depends on X86_64
  32. option defconfig_list
  33. default "arch/x86/configs/x86_64_defconfig"
  34. config GENERIC_LOCKBREAK
  35. def_bool n
  36. config GENERIC_TIME
  37. def_bool y
  38. config GENERIC_CMOS_UPDATE
  39. def_bool y
  40. config CLOCKSOURCE_WATCHDOG
  41. def_bool y
  42. config GENERIC_CLOCKEVENTS
  43. def_bool y
  44. config GENERIC_CLOCKEVENTS_BROADCAST
  45. def_bool y
  46. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  47. config LOCKDEP_SUPPORT
  48. def_bool y
  49. config STACKTRACE_SUPPORT
  50. def_bool y
  51. config HAVE_LATENCYTOP_SUPPORT
  52. def_bool y
  53. config FAST_CMPXCHG_LOCAL
  54. bool
  55. default y
  56. config MMU
  57. def_bool y
  58. config ZONE_DMA
  59. def_bool y
  60. config SBUS
  61. bool
  62. config GENERIC_ISA_DMA
  63. def_bool y
  64. config GENERIC_IOMAP
  65. def_bool y
  66. config GENERIC_BUG
  67. def_bool y
  68. depends on BUG
  69. config GENERIC_HWEIGHT
  70. def_bool y
  71. config GENERIC_GPIO
  72. def_bool n
  73. config ARCH_MAY_HAVE_PC_FDC
  74. def_bool y
  75. config RWSEM_GENERIC_SPINLOCK
  76. def_bool !X86_XADD
  77. config RWSEM_XCHGADD_ALGORITHM
  78. def_bool X86_XADD
  79. config ARCH_HAS_ILOG2_U32
  80. def_bool n
  81. config ARCH_HAS_ILOG2_U64
  82. def_bool n
  83. config ARCH_HAS_CPU_IDLE_WAIT
  84. def_bool y
  85. config GENERIC_CALIBRATE_DELAY
  86. def_bool y
  87. config GENERIC_TIME_VSYSCALL
  88. bool
  89. default X86_64
  90. config ARCH_HAS_CPU_RELAX
  91. def_bool y
  92. config ARCH_HAS_CACHE_LINE_SIZE
  93. def_bool y
  94. config HAVE_SETUP_PER_CPU_AREA
  95. def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
  96. config HAVE_CPUMASK_OF_CPU_MAP
  97. def_bool X86_64_SMP
  98. config ARCH_HIBERNATION_POSSIBLE
  99. def_bool y
  100. depends on !SMP || !X86_VOYAGER
  101. config ARCH_SUSPEND_POSSIBLE
  102. def_bool y
  103. depends on !X86_VOYAGER
  104. config ZONE_DMA32
  105. bool
  106. default X86_64
  107. config ARCH_POPULATES_NODE_MAP
  108. def_bool y
  109. config AUDIT_ARCH
  110. bool
  111. default X86_64
  112. config ARCH_SUPPORTS_AOUT
  113. def_bool y
  114. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  115. def_bool y
  116. # Use the generic interrupt handling code in kernel/irq/:
  117. config GENERIC_HARDIRQS
  118. bool
  119. default y
  120. config GENERIC_IRQ_PROBE
  121. bool
  122. default y
  123. config GENERIC_PENDING_IRQ
  124. bool
  125. depends on GENERIC_HARDIRQS && SMP
  126. default y
  127. config X86_SMP
  128. bool
  129. depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
  130. default y
  131. config X86_32_SMP
  132. def_bool y
  133. depends on X86_32 && SMP
  134. config X86_64_SMP
  135. def_bool y
  136. depends on X86_64 && SMP
  137. config X86_HT
  138. bool
  139. depends on SMP
  140. depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
  141. default y
  142. config X86_BIOS_REBOOT
  143. bool
  144. depends on !X86_VISWS && !X86_VOYAGER
  145. default y
  146. config X86_TRAMPOLINE
  147. bool
  148. depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
  149. default y
  150. config KTIME_SCALAR
  151. def_bool X86_32
  152. source "init/Kconfig"
  153. menu "Processor type and features"
  154. source "kernel/time/Kconfig"
  155. config SMP
  156. bool "Symmetric multi-processing support"
  157. ---help---
  158. This enables support for systems with more than one CPU. If you have
  159. a system with only one CPU, like most personal computers, say N. If
  160. you have a system with more than one CPU, say Y.
  161. If you say N here, the kernel will run on single and multiprocessor
  162. machines, but will use only one CPU of a multiprocessor machine. If
  163. you say Y here, the kernel will run on many, but not all,
  164. singleprocessor machines. On a singleprocessor machine, the kernel
  165. will run faster if you say N here.
  166. Note that if you say Y here and choose architecture "586" or
  167. "Pentium" under "Processor family", the kernel will not work on 486
  168. architectures. Similarly, multiprocessor kernels for the "PPro"
  169. architecture may not work on all Pentium based boards.
  170. People using multiprocessor machines who say Y here should also say
  171. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  172. Management" code will be disabled if you say Y here.
  173. See also <file:Documentation/i386/IO-APIC.txt>,
  174. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  175. <http://www.tldp.org/docs.html#howto>.
  176. If you don't know what to do here, say N.
  177. choice
  178. prompt "Subarchitecture Type"
  179. default X86_PC
  180. config X86_PC
  181. bool "PC-compatible"
  182. help
  183. Choose this option if your computer is a standard PC or compatible.
  184. config X86_ELAN
  185. bool "AMD Elan"
  186. depends on X86_32
  187. help
  188. Select this for an AMD Elan processor.
  189. Do not use this option for K6/Athlon/Opteron processors!
  190. If unsure, choose "PC-compatible" instead.
  191. config X86_VOYAGER
  192. bool "Voyager (NCR)"
  193. depends on X86_32 && (SMP || BROKEN)
  194. help
  195. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  196. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  197. *** WARNING ***
  198. If you do not specifically know you have a Voyager based machine,
  199. say N here, otherwise the kernel you build will not be bootable.
  200. config X86_NUMAQ
  201. bool "NUMAQ (IBM/Sequent)"
  202. depends on SMP && X86_32
  203. select NUMA
  204. help
  205. This option is used for getting Linux to run on a (IBM/Sequent) NUMA
  206. multiquad box. This changes the way that processors are bootstrapped,
  207. and uses Clustered Logical APIC addressing mode instead of Flat Logical.
  208. You will need a new lynxer.elf file to flash your firmware with - send
  209. email to <Martin.Bligh@us.ibm.com>.
  210. config X86_SUMMIT
  211. bool "Summit/EXA (IBM x440)"
  212. depends on X86_32 && SMP
  213. help
  214. This option is needed for IBM systems that use the Summit/EXA chipset.
  215. In particular, it is needed for the x440.
  216. If you don't have one of these computers, you should say N here.
  217. If you want to build a NUMA kernel, you must select ACPI.
  218. config X86_BIGSMP
  219. bool "Support for other sub-arch SMP systems with more than 8 CPUs"
  220. depends on X86_32 && SMP
  221. help
  222. This option is needed for the systems that have more than 8 CPUs
  223. and if the system is not of any sub-arch type above.
  224. If you don't have such a system, you should say N here.
  225. config X86_VISWS
  226. bool "SGI 320/540 (Visual Workstation)"
  227. depends on X86_32
  228. help
  229. The SGI Visual Workstation series is an IA32-based workstation
  230. based on SGI systems chips with some legacy PC hardware attached.
  231. Say Y here to create a kernel to run on the SGI 320 or 540.
  232. A kernel compiled for the Visual Workstation will not run on PCs
  233. and vice versa. See <file:Documentation/sgi-visws.txt> for details.
  234. config X86_GENERICARCH
  235. bool "Generic architecture (Summit, bigsmp, ES7000, default)"
  236. depends on X86_32
  237. help
  238. This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
  239. It is intended for a generic binary kernel.
  240. If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
  241. config X86_ES7000
  242. bool "Support for Unisys ES7000 IA32 series"
  243. depends on X86_32 && SMP
  244. help
  245. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  246. supposed to run on an IA32-based Unisys ES7000 system.
  247. Only choose this option if you have such a system, otherwise you
  248. should say N here.
  249. config X86_RDC321X
  250. bool "RDC R-321x SoC"
  251. depends on X86_32
  252. select M486
  253. select X86_REBOOTFIXUPS
  254. select GENERIC_GPIO
  255. select LEDS_CLASS
  256. select LEDS_GPIO
  257. help
  258. This option is needed for RDC R-321x system-on-chip, also known
  259. as R-8610-(G).
  260. If you don't have one of these chips, you should say N here.
  261. config X86_VSMP
  262. bool "Support for ScaleMP vSMP"
  263. select PARAVIRT
  264. depends on X86_64
  265. help
  266. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  267. supposed to run on these EM64T-based machines. Only choose this option
  268. if you have one of these machines.
  269. endchoice
  270. config SCHED_NO_NO_OMIT_FRAME_POINTER
  271. def_bool y
  272. prompt "Single-depth WCHAN output"
  273. depends on X86_32
  274. help
  275. Calculate simpler /proc/<PID>/wchan values. If this option
  276. is disabled then wchan values will recurse back to the
  277. caller function. This provides more accurate wchan values,
  278. at the expense of slightly more scheduling overhead.
  279. If in doubt, say "Y".
  280. menuconfig PARAVIRT_GUEST
  281. bool "Paravirtualized guest support"
  282. help
  283. Say Y here to get to see options related to running Linux under
  284. various hypervisors. This option alone does not add any kernel code.
  285. If you say N, all options in this submenu will be skipped and disabled.
  286. if PARAVIRT_GUEST
  287. source "arch/x86/xen/Kconfig"
  288. config VMI
  289. bool "VMI Guest support"
  290. select PARAVIRT
  291. depends on X86_32
  292. depends on !(X86_VISWS || X86_VOYAGER)
  293. help
  294. VMI provides a paravirtualized interface to the VMware ESX server
  295. (it could be used by other hypervisors in theory too, but is not
  296. at the moment), by linking the kernel to a GPL-ed ROM module
  297. provided by the hypervisor.
  298. config KVM_CLOCK
  299. bool "KVM paravirtualized clock"
  300. select PARAVIRT
  301. depends on !(X86_VISWS || X86_VOYAGER)
  302. help
  303. Turning on this option will allow you to run a paravirtualized clock
  304. when running over the KVM hypervisor. Instead of relying on a PIT
  305. (or probably other) emulation by the underlying device model, the host
  306. provides the guest with timing infrastructure such as time of day, and
  307. system time
  308. config KVM_GUEST
  309. bool "KVM Guest support"
  310. select PARAVIRT
  311. depends on !(X86_VISWS || X86_VOYAGER)
  312. help
  313. This option enables various optimizations for running under the KVM
  314. hypervisor.
  315. source "arch/x86/lguest/Kconfig"
  316. config PARAVIRT
  317. bool "Enable paravirtualization code"
  318. depends on !(X86_VISWS || X86_VOYAGER)
  319. help
  320. This changes the kernel so it can modify itself when it is run
  321. under a hypervisor, potentially improving performance significantly
  322. over full virtualization. However, when run without a hypervisor
  323. the kernel is theoretically slower and slightly larger.
  324. endif
  325. config MEMTEST_BOOTPARAM
  326. bool "Memtest boot parameter"
  327. depends on X86_64
  328. default y
  329. help
  330. This option adds a kernel parameter 'memtest', which allows memtest
  331. to be disabled at boot. If this option is selected, memtest
  332. functionality can be disabled with memtest=0 on the kernel
  333. command line. The purpose of this option is to allow a single
  334. kernel image to be distributed with memtest built in, but not
  335. necessarily enabled.
  336. If you are unsure how to answer this question, answer Y.
  337. config MEMTEST_BOOTPARAM_VALUE
  338. int "Memtest boot parameter default value (0-4)"
  339. depends on MEMTEST_BOOTPARAM
  340. range 0 4
  341. default 0
  342. help
  343. This option sets the default value for the kernel parameter
  344. 'memtest', which allows memtest to be disabled at boot. If this
  345. option is set to 0 (zero), the memtest kernel parameter will
  346. default to 0, disabling memtest at bootup. If this option is
  347. set to 4, the memtest kernel parameter will default to 4,
  348. enabling memtest at bootup, and use that as pattern number.
  349. If you are unsure how to answer this question, answer 0.
  350. config ACPI_SRAT
  351. def_bool y
  352. depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  353. select ACPI_NUMA
  354. config HAVE_ARCH_PARSE_SRAT
  355. def_bool y
  356. depends on ACPI_SRAT
  357. config X86_SUMMIT_NUMA
  358. def_bool y
  359. depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  360. config X86_CYCLONE_TIMER
  361. def_bool y
  362. depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
  363. config ES7000_CLUSTERED_APIC
  364. def_bool y
  365. depends on SMP && X86_ES7000 && MPENTIUMIII
  366. source "arch/x86/Kconfig.cpu"
  367. config HPET_TIMER
  368. def_bool X86_64
  369. prompt "HPET Timer Support" if X86_32
  370. help
  371. Use the IA-PC HPET (High Precision Event Timer) to manage
  372. time in preference to the PIT and RTC, if a HPET is
  373. present.
  374. HPET is the next generation timer replacing legacy 8254s.
  375. The HPET provides a stable time base on SMP
  376. systems, unlike the TSC, but it is more expensive to access,
  377. as it is off-chip. You can find the HPET spec at
  378. <http://www.intel.com/hardwaredesign/hpetspec.htm>.
  379. You can safely choose Y here. However, HPET will only be
  380. activated if the platform and the BIOS support this feature.
  381. Otherwise the 8254 will be used for timing services.
  382. Choose N to continue using the legacy 8254 timer.
  383. config HPET_EMULATE_RTC
  384. def_bool y
  385. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  386. # Mark as embedded because too many people got it wrong.
  387. # The code disables itself when not needed.
  388. config DMI
  389. default y
  390. bool "Enable DMI scanning" if EMBEDDED
  391. help
  392. Enabled scanning of DMI to identify machine quirks. Say Y
  393. here unless you have verified that your setup is not
  394. affected by entries in the DMI blacklist. Required by PNP
  395. BIOS code.
  396. config GART_IOMMU
  397. bool "GART IOMMU support" if EMBEDDED
  398. default y
  399. select SWIOTLB
  400. select AGP
  401. depends on X86_64 && PCI
  402. help
  403. Support for full DMA access of devices with 32bit memory access only
  404. on systems with more than 3GB. This is usually needed for USB,
  405. sound, many IDE/SATA chipsets and some other devices.
  406. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  407. based hardware IOMMU and a software bounce buffer based IOMMU used
  408. on Intel systems and as fallback.
  409. The code is only active when needed (enough memory and limited
  410. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  411. too.
  412. config CALGARY_IOMMU
  413. bool "IBM Calgary IOMMU support"
  414. select SWIOTLB
  415. depends on X86_64 && PCI && EXPERIMENTAL
  416. help
  417. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  418. systems. Needed to run systems with more than 3GB of memory
  419. properly with 32-bit PCI devices that do not support DAC
  420. (Double Address Cycle). Calgary also supports bus level
  421. isolation, where all DMAs pass through the IOMMU. This
  422. prevents them from going anywhere except their intended
  423. destination. This catches hard-to-find kernel bugs and
  424. mis-behaving drivers and devices that do not use the DMA-API
  425. properly to set up their DMA buffers. The IOMMU can be
  426. turned off at boot time with the iommu=off parameter.
  427. Normally the kernel will make the right choice by itself.
  428. If unsure, say Y.
  429. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  430. def_bool y
  431. prompt "Should Calgary be enabled by default?"
  432. depends on CALGARY_IOMMU
  433. help
  434. Should Calgary be enabled by default? if you choose 'y', Calgary
  435. will be used (if it exists). If you choose 'n', Calgary will not be
  436. used even if it exists. If you choose 'n' and would like to use
  437. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  438. If unsure, say Y.
  439. # need this always selected by IOMMU for the VIA workaround
  440. config SWIOTLB
  441. bool
  442. help
  443. Support for software bounce buffers used on x86-64 systems
  444. which don't have a hardware IOMMU (e.g. the current generation
  445. of Intel's x86-64 CPUs). Using this PCI devices which can only
  446. access 32-bits of memory can be used on systems with more than
  447. 3 GB of memory. If unsure, say Y.
  448. config IOMMU_HELPER
  449. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
  450. config NR_CPUS
  451. int "Maximum number of CPUs (2-255)"
  452. range 2 255
  453. depends on SMP
  454. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  455. default "8"
  456. help
  457. This allows you to specify the maximum number of CPUs which this
  458. kernel will support. The maximum supported value is 255 and the
  459. minimum value which makes sense is 2.
  460. This is purely to save memory - each supported CPU adds
  461. approximately eight kilobytes to the kernel image.
  462. config SCHED_SMT
  463. bool "SMT (Hyperthreading) scheduler support"
  464. depends on X86_HT
  465. help
  466. SMT scheduler support improves the CPU scheduler's decision making
  467. when dealing with Intel Pentium 4 chips with HyperThreading at a
  468. cost of slightly increased overhead in some places. If unsure say
  469. N here.
  470. config SCHED_MC
  471. def_bool y
  472. prompt "Multi-core scheduler support"
  473. depends on X86_HT
  474. help
  475. Multi-core scheduler support improves the CPU scheduler's decision
  476. making when dealing with multi-core CPU chips at a cost of slightly
  477. increased overhead in some places. If unsure say N here.
  478. source "kernel/Kconfig.preempt"
  479. config X86_UP_APIC
  480. bool "Local APIC support on uniprocessors"
  481. depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
  482. help
  483. A local APIC (Advanced Programmable Interrupt Controller) is an
  484. integrated interrupt controller in the CPU. If you have a single-CPU
  485. system which has a processor with a local APIC, you can say Y here to
  486. enable and use it. If you say Y here even though your machine doesn't
  487. have a local APIC, then the kernel will still run with no slowdown at
  488. all. The local APIC supports CPU-generated self-interrupts (timer,
  489. performance counters), and the NMI watchdog which detects hard
  490. lockups.
  491. config X86_UP_IOAPIC
  492. bool "IO-APIC support on uniprocessors"
  493. depends on X86_UP_APIC
  494. help
  495. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  496. SMP-capable replacement for PC-style interrupt controllers. Most
  497. SMP systems and many recent uniprocessor systems have one.
  498. If you have a single-CPU system with an IO-APIC, you can say Y here
  499. to use it. If you say Y here even though your machine doesn't have
  500. an IO-APIC, then the kernel will still run with no slowdown at all.
  501. config X86_LOCAL_APIC
  502. def_bool y
  503. depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
  504. config X86_IO_APIC
  505. def_bool y
  506. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
  507. config X86_VISWS_APIC
  508. def_bool y
  509. depends on X86_32 && X86_VISWS
  510. config X86_MCE
  511. bool "Machine Check Exception"
  512. depends on !X86_VOYAGER
  513. ---help---
  514. Machine Check Exception support allows the processor to notify the
  515. kernel if it detects a problem (e.g. overheating, component failure).
  516. The action the kernel takes depends on the severity of the problem,
  517. ranging from a warning message on the console, to halting the machine.
  518. Your processor must be a Pentium or newer to support this - check the
  519. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  520. have a design flaw which leads to false MCE events - hence MCE is
  521. disabled on all P5 processors, unless explicitly enabled with "mce"
  522. as a boot argument. Similarly, if MCE is built in and creates a
  523. problem on some new non-standard machine, you can boot with "nomce"
  524. to disable it. MCE support simply ignores non-MCE processors like
  525. the 386 and 486, so nearly everyone can say Y here.
  526. config X86_MCE_INTEL
  527. def_bool y
  528. prompt "Intel MCE features"
  529. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  530. help
  531. Additional support for intel specific MCE features such as
  532. the thermal monitor.
  533. config X86_MCE_AMD
  534. def_bool y
  535. prompt "AMD MCE features"
  536. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  537. help
  538. Additional support for AMD specific MCE features such as
  539. the DRAM Error Threshold.
  540. config X86_MCE_NONFATAL
  541. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  542. depends on X86_32 && X86_MCE
  543. help
  544. Enabling this feature starts a timer that triggers every 5 seconds which
  545. will look at the machine check registers to see if anything happened.
  546. Non-fatal problems automatically get corrected (but still logged).
  547. Disable this if you don't want to see these messages.
  548. Seeing the messages this option prints out may be indicative of dying
  549. or out-of-spec (ie, overclocked) hardware.
  550. This option only does something on certain CPUs.
  551. (AMD Athlon/Duron and Intel Pentium 4)
  552. config X86_MCE_P4THERMAL
  553. bool "check for P4 thermal throttling interrupt."
  554. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
  555. help
  556. Enabling this feature will cause a message to be printed when the P4
  557. enters thermal throttling.
  558. config VM86
  559. bool "Enable VM86 support" if EMBEDDED
  560. default y
  561. depends on X86_32
  562. help
  563. This option is required by programs like DOSEMU to run 16-bit legacy
  564. code on X86 processors. It also may be needed by software like
  565. XFree86 to initialize some video cards via BIOS. Disabling this
  566. option saves about 6k.
  567. config TOSHIBA
  568. tristate "Toshiba Laptop support"
  569. depends on X86_32
  570. ---help---
  571. This adds a driver to safely access the System Management Mode of
  572. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  573. not work on models with a Phoenix BIOS. The System Management Mode
  574. is used to set the BIOS and power saving options on Toshiba portables.
  575. For information on utilities to make use of this driver see the
  576. Toshiba Linux utilities web site at:
  577. <http://www.buzzard.org.uk/toshiba/>.
  578. Say Y if you intend to run this kernel on a Toshiba portable.
  579. Say N otherwise.
  580. config I8K
  581. tristate "Dell laptop support"
  582. ---help---
  583. This adds a driver to safely access the System Management Mode
  584. of the CPU on the Dell Inspiron 8000. The System Management Mode
  585. is used to read cpu temperature and cooling fan status and to
  586. control the fans on the I8K portables.
  587. This driver has been tested only on the Inspiron 8000 but it may
  588. also work with other Dell laptops. You can force loading on other
  589. models by passing the parameter `force=1' to the module. Use at
  590. your own risk.
  591. For information on utilities to make use of this driver see the
  592. I8K Linux utilities web site at:
  593. <http://people.debian.org/~dz/i8k/>
  594. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  595. Say N otherwise.
  596. config X86_REBOOTFIXUPS
  597. def_bool n
  598. prompt "Enable X86 board specific fixups for reboot"
  599. depends on X86_32 && X86
  600. ---help---
  601. This enables chipset and/or board specific fixups to be done
  602. in order to get reboot to work correctly. This is only needed on
  603. some combinations of hardware and BIOS. The symptom, for which
  604. this config is intended, is when reboot ends with a stalled/hung
  605. system.
  606. Currently, the only fixup is for the Geode machines using
  607. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  608. Say Y if you want to enable the fixup. Currently, it's safe to
  609. enable this option even if you don't need it.
  610. Say N otherwise.
  611. config MICROCODE
  612. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  613. select FW_LOADER
  614. ---help---
  615. If you say Y here, you will be able to update the microcode on
  616. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  617. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  618. actual microcode binary data itself which is not shipped with the
  619. Linux kernel.
  620. For latest news and information on obtaining all the required
  621. ingredients for this driver, check:
  622. <http://www.urbanmyth.org/microcode/>.
  623. To compile this driver as a module, choose M here: the
  624. module will be called microcode.
  625. config MICROCODE_OLD_INTERFACE
  626. def_bool y
  627. depends on MICROCODE
  628. config X86_MSR
  629. tristate "/dev/cpu/*/msr - Model-specific register support"
  630. help
  631. This device gives privileged processes access to the x86
  632. Model-Specific Registers (MSRs). It is a character device with
  633. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  634. MSR accesses are directed to a specific CPU on multi-processor
  635. systems.
  636. config X86_CPUID
  637. tristate "/dev/cpu/*/cpuid - CPU information support"
  638. help
  639. This device gives processes access to the x86 CPUID instruction to
  640. be executed on a specific processor. It is a character device
  641. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  642. /dev/cpu/31/cpuid.
  643. choice
  644. prompt "High Memory Support"
  645. default HIGHMEM4G if !X86_NUMAQ
  646. default HIGHMEM64G if X86_NUMAQ
  647. depends on X86_32
  648. config NOHIGHMEM
  649. bool "off"
  650. depends on !X86_NUMAQ
  651. ---help---
  652. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  653. However, the address space of 32-bit x86 processors is only 4
  654. Gigabytes large. That means that, if you have a large amount of
  655. physical memory, not all of it can be "permanently mapped" by the
  656. kernel. The physical memory that's not permanently mapped is called
  657. "high memory".
  658. If you are compiling a kernel which will never run on a machine with
  659. more than 1 Gigabyte total physical RAM, answer "off" here (default
  660. choice and suitable for most users). This will result in a "3GB/1GB"
  661. split: 3GB are mapped so that each process sees a 3GB virtual memory
  662. space and the remaining part of the 4GB virtual memory space is used
  663. by the kernel to permanently map as much physical memory as
  664. possible.
  665. If the machine has between 1 and 4 Gigabytes physical RAM, then
  666. answer "4GB" here.
  667. If more than 4 Gigabytes is used then answer "64GB" here. This
  668. selection turns Intel PAE (Physical Address Extension) mode on.
  669. PAE implements 3-level paging on IA32 processors. PAE is fully
  670. supported by Linux, PAE mode is implemented on all recent Intel
  671. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  672. then the kernel will not boot on CPUs that don't support PAE!
  673. The actual amount of total physical memory will either be
  674. auto detected or can be forced by using a kernel command line option
  675. such as "mem=256M". (Try "man bootparam" or see the documentation of
  676. your boot loader (lilo or loadlin) about how to pass options to the
  677. kernel at boot time.)
  678. If unsure, say "off".
  679. config HIGHMEM4G
  680. bool "4GB"
  681. depends on !X86_NUMAQ
  682. help
  683. Select this if you have a 32-bit processor and between 1 and 4
  684. gigabytes of physical RAM.
  685. config HIGHMEM64G
  686. bool "64GB"
  687. depends on !M386 && !M486
  688. select X86_PAE
  689. help
  690. Select this if you have a 32-bit processor and more than 4
  691. gigabytes of physical RAM.
  692. endchoice
  693. choice
  694. depends on EXPERIMENTAL
  695. prompt "Memory split" if EMBEDDED
  696. default VMSPLIT_3G
  697. depends on X86_32
  698. help
  699. Select the desired split between kernel and user memory.
  700. If the address range available to the kernel is less than the
  701. physical memory installed, the remaining memory will be available
  702. as "high memory". Accessing high memory is a little more costly
  703. than low memory, as it needs to be mapped into the kernel first.
  704. Note that increasing the kernel address space limits the range
  705. available to user programs, making the address space there
  706. tighter. Selecting anything other than the default 3G/1G split
  707. will also likely make your kernel incompatible with binary-only
  708. kernel modules.
  709. If you are not absolutely sure what you are doing, leave this
  710. option alone!
  711. config VMSPLIT_3G
  712. bool "3G/1G user/kernel split"
  713. config VMSPLIT_3G_OPT
  714. depends on !X86_PAE
  715. bool "3G/1G user/kernel split (for full 1G low memory)"
  716. config VMSPLIT_2G
  717. bool "2G/2G user/kernel split"
  718. config VMSPLIT_2G_OPT
  719. depends on !X86_PAE
  720. bool "2G/2G user/kernel split (for full 2G low memory)"
  721. config VMSPLIT_1G
  722. bool "1G/3G user/kernel split"
  723. endchoice
  724. config PAGE_OFFSET
  725. hex
  726. default 0xB0000000 if VMSPLIT_3G_OPT
  727. default 0x80000000 if VMSPLIT_2G
  728. default 0x78000000 if VMSPLIT_2G_OPT
  729. default 0x40000000 if VMSPLIT_1G
  730. default 0xC0000000
  731. depends on X86_32
  732. config HIGHMEM
  733. def_bool y
  734. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  735. config X86_PAE
  736. def_bool n
  737. prompt "PAE (Physical Address Extension) Support"
  738. depends on X86_32 && !HIGHMEM4G
  739. select RESOURCES_64BIT
  740. help
  741. PAE is required for NX support, and furthermore enables
  742. larger swapspace support for non-overcommit purposes. It
  743. has the cost of more pagetable lookup overhead, and also
  744. consumes more pagetable space per process.
  745. # Common NUMA Features
  746. config NUMA
  747. bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
  748. depends on SMP
  749. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
  750. default n if X86_PC
  751. default y if (X86_NUMAQ || X86_SUMMIT)
  752. help
  753. Enable NUMA (Non Uniform Memory Access) support.
  754. The kernel will try to allocate memory used by a CPU on the
  755. local memory controller of the CPU and add some more
  756. NUMA awareness to the kernel.
  757. For i386 this is currently highly experimental and should be only
  758. used for kernel development. It might also cause boot failures.
  759. For x86_64 this is recommended on all multiprocessor Opteron systems.
  760. If the system is EM64T, you should say N unless your system is
  761. EM64T NUMA.
  762. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  763. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  764. config K8_NUMA
  765. def_bool y
  766. prompt "Old style AMD Opteron NUMA detection"
  767. depends on X86_64 && NUMA && PCI
  768. help
  769. Enable K8 NUMA node topology detection. You should say Y here if
  770. you have a multi processor AMD K8 system. This uses an old
  771. method to read the NUMA configuration directly from the builtin
  772. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  773. instead, which also takes priority if both are compiled in.
  774. config X86_64_ACPI_NUMA
  775. def_bool y
  776. prompt "ACPI NUMA detection"
  777. depends on X86_64 && NUMA && ACPI && PCI
  778. select ACPI_NUMA
  779. help
  780. Enable ACPI SRAT based node topology detection.
  781. # Some NUMA nodes have memory ranges that span
  782. # other nodes. Even though a pfn is valid and
  783. # between a node's start and end pfns, it may not
  784. # reside on that node. See memmap_init_zone()
  785. # for details.
  786. config NODES_SPAN_OTHER_NODES
  787. def_bool y
  788. depends on X86_64_ACPI_NUMA
  789. config NUMA_EMU
  790. bool "NUMA emulation"
  791. depends on X86_64 && NUMA
  792. help
  793. Enable NUMA emulation. A flat machine will be split
  794. into virtual nodes when booted with "numa=fake=N", where N is the
  795. number of nodes. This is only useful for debugging.
  796. config NODES_SHIFT
  797. int "Max num nodes shift(1-15)"
  798. range 1 15 if X86_64
  799. default "6" if X86_64
  800. default "4" if X86_NUMAQ
  801. default "3"
  802. depends on NEED_MULTIPLE_NODES
  803. config HAVE_ARCH_BOOTMEM_NODE
  804. def_bool y
  805. depends on X86_32 && NUMA
  806. config ARCH_HAVE_MEMORY_PRESENT
  807. def_bool y
  808. depends on X86_32 && DISCONTIGMEM
  809. config NEED_NODE_MEMMAP_SIZE
  810. def_bool y
  811. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  812. config HAVE_ARCH_ALLOC_REMAP
  813. def_bool y
  814. depends on X86_32 && NUMA
  815. config ARCH_FLATMEM_ENABLE
  816. def_bool y
  817. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
  818. config ARCH_DISCONTIGMEM_ENABLE
  819. def_bool y
  820. depends on NUMA && X86_32
  821. config ARCH_DISCONTIGMEM_DEFAULT
  822. def_bool y
  823. depends on NUMA && X86_32
  824. config ARCH_SPARSEMEM_DEFAULT
  825. def_bool y
  826. depends on X86_64
  827. config ARCH_SPARSEMEM_ENABLE
  828. def_bool y
  829. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
  830. select SPARSEMEM_STATIC if X86_32
  831. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  832. config ARCH_SELECT_MEMORY_MODEL
  833. def_bool y
  834. depends on ARCH_SPARSEMEM_ENABLE
  835. config ARCH_MEMORY_PROBE
  836. def_bool X86_64
  837. depends on MEMORY_HOTPLUG
  838. source "mm/Kconfig"
  839. config HIGHPTE
  840. bool "Allocate 3rd-level pagetables from highmem"
  841. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  842. help
  843. The VM uses one page table entry for each page of physical memory.
  844. For systems with a lot of RAM, this can be wasteful of precious
  845. low memory. Setting this option will put user-space page table
  846. entries in high memory.
  847. config MATH_EMULATION
  848. bool
  849. prompt "Math emulation" if X86_32
  850. ---help---
  851. Linux can emulate a math coprocessor (used for floating point
  852. operations) if you don't have one. 486DX and Pentium processors have
  853. a math coprocessor built in, 486SX and 386 do not, unless you added
  854. a 487DX or 387, respectively. (The messages during boot time can
  855. give you some hints here ["man dmesg"].) Everyone needs either a
  856. coprocessor or this emulation.
  857. If you don't have a math coprocessor, you need to say Y here; if you
  858. say Y here even though you have a coprocessor, the coprocessor will
  859. be used nevertheless. (This behavior can be changed with the kernel
  860. command line option "no387", which comes handy if your coprocessor
  861. is broken. Try "man bootparam" or see the documentation of your boot
  862. loader (lilo or loadlin) about how to pass options to the kernel at
  863. boot time.) This means that it is a good idea to say Y here if you
  864. intend to use this kernel on different machines.
  865. More information about the internals of the Linux math coprocessor
  866. emulation can be found in <file:arch/x86/math-emu/README>.
  867. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  868. kernel, it won't hurt.
  869. config MTRR
  870. bool "MTRR (Memory Type Range Register) support"
  871. ---help---
  872. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  873. the Memory Type Range Registers (MTRRs) may be used to control
  874. processor access to memory ranges. This is most useful if you have
  875. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  876. allows bus write transfers to be combined into a larger transfer
  877. before bursting over the PCI/AGP bus. This can increase performance
  878. of image write operations 2.5 times or more. Saying Y here creates a
  879. /proc/mtrr file which may be used to manipulate your processor's
  880. MTRRs. Typically the X server should use this.
  881. This code has a reasonably generic interface so that similar
  882. control registers on other processors can be easily supported
  883. as well:
  884. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  885. Registers (ARRs) which provide a similar functionality to MTRRs. For
  886. these, the ARRs are used to emulate the MTRRs.
  887. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  888. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  889. write-combining. All of these processors are supported by this code
  890. and it makes sense to say Y here if you have one of them.
  891. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  892. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  893. can lead to all sorts of problems, so it's good to say Y here.
  894. You can safely say Y even if your machine doesn't have MTRRs, you'll
  895. just add about 9 KB to your kernel.
  896. See <file:Documentation/mtrr.txt> for more information.
  897. config X86_PAT
  898. bool
  899. prompt "x86 PAT support"
  900. depends on MTRR
  901. help
  902. Use PAT attributes to setup page level cache control.
  903. PATs are the modern equivalents of MTRRs and are much more
  904. flexible than MTRRs.
  905. Say N here if you see bootup problems (boot crash, boot hang,
  906. spontaneous reboots) or a non-working video driver.
  907. If unsure, say Y.
  908. config EFI
  909. def_bool n
  910. prompt "EFI runtime service support"
  911. depends on ACPI
  912. ---help---
  913. This enables the kernel to use EFI runtime services that are
  914. available (such as the EFI variable services).
  915. This option is only useful on systems that have EFI firmware.
  916. In addition, you should use the latest ELILO loader available
  917. at <http://elilo.sourceforge.net> in order to take advantage
  918. of EFI runtime services. However, even with this option, the
  919. resultant kernel should continue to boot on existing non-EFI
  920. platforms.
  921. config IRQBALANCE
  922. def_bool y
  923. prompt "Enable kernel irq balancing"
  924. depends on X86_32 && SMP && X86_IO_APIC
  925. help
  926. The default yes will allow the kernel to do irq load balancing.
  927. Saying no will keep the kernel from doing irq load balancing.
  928. config SECCOMP
  929. def_bool y
  930. prompt "Enable seccomp to safely compute untrusted bytecode"
  931. depends on PROC_FS
  932. help
  933. This kernel feature is useful for number crunching applications
  934. that may need to compute untrusted bytecode during their
  935. execution. By using pipes or other transports made available to
  936. the process as file descriptors supporting the read/write
  937. syscalls, it's possible to isolate those applications in
  938. their own address space using seccomp. Once seccomp is
  939. enabled via /proc/<pid>/seccomp, it cannot be disabled
  940. and the task is only allowed to execute a few safe syscalls
  941. defined by each seccomp mode.
  942. If unsure, say Y. Only embedded should say N here.
  943. config CC_STACKPROTECTOR
  944. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  945. depends on X86_64 && EXPERIMENTAL && BROKEN
  946. help
  947. This option turns on the -fstack-protector GCC feature. This
  948. feature puts, at the beginning of critical functions, a canary
  949. value on the stack just before the return address, and validates
  950. the value just before actually returning. Stack based buffer
  951. overflows (that need to overwrite this return address) now also
  952. overwrite the canary, which gets detected and the attack is then
  953. neutralized via a kernel panic.
  954. This feature requires gcc version 4.2 or above, or a distribution
  955. gcc with the feature backported. Older versions are automatically
  956. detected and for those versions, this configuration option is ignored.
  957. config CC_STACKPROTECTOR_ALL
  958. bool "Use stack-protector for all functions"
  959. depends on CC_STACKPROTECTOR
  960. help
  961. Normally, GCC only inserts the canary value protection for
  962. functions that use large-ish on-stack buffers. By enabling
  963. this option, GCC will be asked to do this for ALL functions.
  964. source kernel/Kconfig.hz
  965. config KEXEC
  966. bool "kexec system call"
  967. depends on X86_BIOS_REBOOT
  968. help
  969. kexec is a system call that implements the ability to shutdown your
  970. current kernel, and to start another kernel. It is like a reboot
  971. but it is independent of the system firmware. And like a reboot
  972. you can start any kernel with it, not just Linux.
  973. The name comes from the similarity to the exec system call.
  974. It is an ongoing process to be certain the hardware in a machine
  975. is properly shutdown, so do not be surprised if this code does not
  976. initially work for you. It may help to enable device hotplugging
  977. support. As of this writing the exact hardware interface is
  978. strongly in flux, so no good recommendation can be made.
  979. config CRASH_DUMP
  980. bool "kernel crash dumps (EXPERIMENTAL)"
  981. depends on EXPERIMENTAL
  982. depends on X86_64 || (X86_32 && HIGHMEM)
  983. help
  984. Generate crash dump after being started by kexec.
  985. This should be normally only set in special crash dump kernels
  986. which are loaded in the main kernel with kexec-tools into
  987. a specially reserved region and then later executed after
  988. a crash by kdump/kexec. The crash dump kernel must be compiled
  989. to a memory address not used by the main kernel or BIOS using
  990. PHYSICAL_START, or it must be built as a relocatable image
  991. (CONFIG_RELOCATABLE=y).
  992. For more details see Documentation/kdump/kdump.txt
  993. config PHYSICAL_START
  994. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  995. default "0x1000000" if X86_NUMAQ
  996. default "0x200000" if X86_64
  997. default "0x100000"
  998. help
  999. This gives the physical address where the kernel is loaded.
  1000. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1001. bzImage will decompress itself to above physical address and
  1002. run from there. Otherwise, bzImage will run from the address where
  1003. it has been loaded by the boot loader and will ignore above physical
  1004. address.
  1005. In normal kdump cases one does not have to set/change this option
  1006. as now bzImage can be compiled as a completely relocatable image
  1007. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1008. address. This option is mainly useful for the folks who don't want
  1009. to use a bzImage for capturing the crash dump and want to use a
  1010. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1011. to be specifically compiled to run from a specific memory area
  1012. (normally a reserved region) and this option comes handy.
  1013. So if you are using bzImage for capturing the crash dump, leave
  1014. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  1015. Otherwise if you plan to use vmlinux for capturing the crash dump
  1016. change this value to start of the reserved region (Typically 16MB
  1017. 0x1000000). In other words, it can be set based on the "X" value as
  1018. specified in the "crashkernel=YM@XM" command line boot parameter
  1019. passed to the panic-ed kernel. Typically this parameter is set as
  1020. crashkernel=64M@16M. Please take a look at
  1021. Documentation/kdump/kdump.txt for more details about crash dumps.
  1022. Usage of bzImage for capturing the crash dump is recommended as
  1023. one does not have to build two kernels. Same kernel can be used
  1024. as production kernel and capture kernel. Above option should have
  1025. gone away after relocatable bzImage support is introduced. But it
  1026. is present because there are users out there who continue to use
  1027. vmlinux for dump capture. This option should go away down the
  1028. line.
  1029. Don't change this unless you know what you are doing.
  1030. config RELOCATABLE
  1031. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1032. depends on EXPERIMENTAL
  1033. help
  1034. This builds a kernel image that retains relocation information
  1035. so it can be loaded someplace besides the default 1MB.
  1036. The relocations tend to make the kernel binary about 10% larger,
  1037. but are discarded at runtime.
  1038. One use is for the kexec on panic case where the recovery kernel
  1039. must live at a different physical address than the primary
  1040. kernel.
  1041. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1042. it has been loaded at and the compile time physical address
  1043. (CONFIG_PHYSICAL_START) is ignored.
  1044. config PHYSICAL_ALIGN
  1045. hex
  1046. prompt "Alignment value to which kernel should be aligned" if X86_32
  1047. default "0x100000" if X86_32
  1048. default "0x200000" if X86_64
  1049. range 0x2000 0x400000
  1050. help
  1051. This value puts the alignment restrictions on physical address
  1052. where kernel is loaded and run from. Kernel is compiled for an
  1053. address which meets above alignment restriction.
  1054. If bootloader loads the kernel at a non-aligned address and
  1055. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1056. address aligned to above value and run from there.
  1057. If bootloader loads the kernel at a non-aligned address and
  1058. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1059. load address and decompress itself to the address it has been
  1060. compiled for and run from there. The address for which kernel is
  1061. compiled already meets above alignment restrictions. Hence the
  1062. end result is that kernel runs from a physical address meeting
  1063. above alignment restrictions.
  1064. Don't change this unless you know what you are doing.
  1065. config HOTPLUG_CPU
  1066. bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
  1067. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  1068. ---help---
  1069. Say Y here to experiment with turning CPUs off and on, and to
  1070. enable suspend on SMP systems. CPUs can be controlled through
  1071. /sys/devices/system/cpu.
  1072. Say N if you want to disable CPU hotplug and don't need to
  1073. suspend.
  1074. config COMPAT_VDSO
  1075. def_bool y
  1076. prompt "Compat VDSO support"
  1077. depends on X86_32 || IA32_EMULATION
  1078. help
  1079. Map the 32-bit VDSO to the predictable old-style address too.
  1080. ---help---
  1081. Say N here if you are running a sufficiently recent glibc
  1082. version (2.3.3 or later), to remove the high-mapped
  1083. VDSO mapping and to exclusively use the randomized VDSO.
  1084. If unsure, say Y.
  1085. endmenu
  1086. config ARCH_ENABLE_MEMORY_HOTPLUG
  1087. def_bool y
  1088. depends on X86_64 || (X86_32 && HIGHMEM)
  1089. config HAVE_ARCH_EARLY_PFN_TO_NID
  1090. def_bool X86_64
  1091. depends on NUMA
  1092. menu "Power management options"
  1093. depends on !X86_VOYAGER
  1094. config ARCH_HIBERNATION_HEADER
  1095. def_bool y
  1096. depends on X86_64 && HIBERNATION
  1097. source "kernel/power/Kconfig"
  1098. source "drivers/acpi/Kconfig"
  1099. config X86_APM_BOOT
  1100. bool
  1101. default y
  1102. depends on APM || APM_MODULE
  1103. menuconfig APM
  1104. tristate "APM (Advanced Power Management) BIOS support"
  1105. depends on X86_32 && PM_SLEEP && !X86_VISWS
  1106. ---help---
  1107. APM is a BIOS specification for saving power using several different
  1108. techniques. This is mostly useful for battery powered laptops with
  1109. APM compliant BIOSes. If you say Y here, the system time will be
  1110. reset after a RESUME operation, the /proc/apm device will provide
  1111. battery status information, and user-space programs will receive
  1112. notification of APM "events" (e.g. battery status change).
  1113. If you select "Y" here, you can disable actual use of the APM
  1114. BIOS by passing the "apm=off" option to the kernel at boot time.
  1115. Note that the APM support is almost completely disabled for
  1116. machines with more than one CPU.
  1117. In order to use APM, you will need supporting software. For location
  1118. and more information, read <file:Documentation/power/pm.txt> and the
  1119. Battery Powered Linux mini-HOWTO, available from
  1120. <http://www.tldp.org/docs.html#howto>.
  1121. This driver does not spin down disk drives (see the hdparm(8)
  1122. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1123. VESA-compliant "green" monitors.
  1124. This driver does not support the TI 4000M TravelMate and the ACER
  1125. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1126. desktop machines also don't have compliant BIOSes, and this driver
  1127. may cause those machines to panic during the boot phase.
  1128. Generally, if you don't have a battery in your machine, there isn't
  1129. much point in using this driver and you should say N. If you get
  1130. random kernel OOPSes or reboots that don't seem to be related to
  1131. anything, try disabling/enabling this option (or disabling/enabling
  1132. APM in your BIOS).
  1133. Some other things you should try when experiencing seemingly random,
  1134. "weird" problems:
  1135. 1) make sure that you have enough swap space and that it is
  1136. enabled.
  1137. 2) pass the "no-hlt" option to the kernel
  1138. 3) switch on floating point emulation in the kernel and pass
  1139. the "no387" option to the kernel
  1140. 4) pass the "floppy=nodma" option to the kernel
  1141. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1142. all but the first 4 MB of RAM)
  1143. 6) make sure that the CPU is not over clocked.
  1144. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1145. 8) disable the cache from your BIOS settings
  1146. 9) install a fan for the video card or exchange video RAM
  1147. 10) install a better fan for the CPU
  1148. 11) exchange RAM chips
  1149. 12) exchange the motherboard.
  1150. To compile this driver as a module, choose M here: the
  1151. module will be called apm.
  1152. if APM
  1153. config APM_IGNORE_USER_SUSPEND
  1154. bool "Ignore USER SUSPEND"
  1155. help
  1156. This option will ignore USER SUSPEND requests. On machines with a
  1157. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1158. series notebooks, it is necessary to say Y because of a BIOS bug.
  1159. config APM_DO_ENABLE
  1160. bool "Enable PM at boot time"
  1161. ---help---
  1162. Enable APM features at boot time. From page 36 of the APM BIOS
  1163. specification: "When disabled, the APM BIOS does not automatically
  1164. power manage devices, enter the Standby State, enter the Suspend
  1165. State, or take power saving steps in response to CPU Idle calls."
  1166. This driver will make CPU Idle calls when Linux is idle (unless this
  1167. feature is turned off -- see "Do CPU IDLE calls", below). This
  1168. should always save battery power, but more complicated APM features
  1169. will be dependent on your BIOS implementation. You may need to turn
  1170. this option off if your computer hangs at boot time when using APM
  1171. support, or if it beeps continuously instead of suspending. Turn
  1172. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1173. T400CDT. This is off by default since most machines do fine without
  1174. this feature.
  1175. config APM_CPU_IDLE
  1176. bool "Make CPU Idle calls when idle"
  1177. help
  1178. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1179. On some machines, this can activate improved power savings, such as
  1180. a slowed CPU clock rate, when the machine is idle. These idle calls
  1181. are made after the idle loop has run for some length of time (e.g.,
  1182. 333 mS). On some machines, this will cause a hang at boot time or
  1183. whenever the CPU becomes idle. (On machines with more than one CPU,
  1184. this option does nothing.)
  1185. config APM_DISPLAY_BLANK
  1186. bool "Enable console blanking using APM"
  1187. help
  1188. Enable console blanking using the APM. Some laptops can use this to
  1189. turn off the LCD backlight when the screen blanker of the Linux
  1190. virtual console blanks the screen. Note that this is only used by
  1191. the virtual console screen blanker, and won't turn off the backlight
  1192. when using the X Window system. This also doesn't have anything to
  1193. do with your VESA-compliant power-saving monitor. Further, this
  1194. option doesn't work for all laptops -- it might not turn off your
  1195. backlight at all, or it might print a lot of errors to the console,
  1196. especially if you are using gpm.
  1197. config APM_ALLOW_INTS
  1198. bool "Allow interrupts during APM BIOS calls"
  1199. help
  1200. Normally we disable external interrupts while we are making calls to
  1201. the APM BIOS as a measure to lessen the effects of a badly behaving
  1202. BIOS implementation. The BIOS should reenable interrupts if it
  1203. needs to. Unfortunately, some BIOSes do not -- especially those in
  1204. many of the newer IBM Thinkpads. If you experience hangs when you
  1205. suspend, try setting this to Y. Otherwise, say N.
  1206. config APM_REAL_MODE_POWER_OFF
  1207. bool "Use real mode APM BIOS call to power off"
  1208. help
  1209. Use real mode APM BIOS calls to switch off the computer. This is
  1210. a work-around for a number of buggy BIOSes. Switch this option on if
  1211. your computer crashes instead of powering off properly.
  1212. endif # APM
  1213. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1214. source "drivers/cpuidle/Kconfig"
  1215. endmenu
  1216. menu "Bus options (PCI etc.)"
  1217. config PCI
  1218. bool "PCI support" if !X86_VISWS && !X86_VSMP
  1219. depends on !X86_VOYAGER
  1220. default y
  1221. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1222. help
  1223. Find out whether you have a PCI motherboard. PCI is the name of a
  1224. bus system, i.e. the way the CPU talks to the other stuff inside
  1225. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1226. VESA. If you have PCI, say Y, otherwise N.
  1227. choice
  1228. prompt "PCI access mode"
  1229. depends on X86_32 && PCI && !X86_VISWS
  1230. default PCI_GOANY
  1231. ---help---
  1232. On PCI systems, the BIOS can be used to detect the PCI devices and
  1233. determine their configuration. However, some old PCI motherboards
  1234. have BIOS bugs and may crash if this is done. Also, some embedded
  1235. PCI-based systems don't have any BIOS at all. Linux can also try to
  1236. detect the PCI hardware directly without using the BIOS.
  1237. With this option, you can specify how Linux should detect the
  1238. PCI devices. If you choose "BIOS", the BIOS will be used,
  1239. if you choose "Direct", the BIOS won't be used, and if you
  1240. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1241. If you choose "Any", the kernel will try MMCONFIG, then the
  1242. direct access method and falls back to the BIOS if that doesn't
  1243. work. If unsure, go with the default, which is "Any".
  1244. config PCI_GOBIOS
  1245. bool "BIOS"
  1246. config PCI_GOMMCONFIG
  1247. bool "MMConfig"
  1248. config PCI_GODIRECT
  1249. bool "Direct"
  1250. config PCI_GOANY
  1251. bool "Any"
  1252. config PCI_GOOLPC
  1253. bool "OLPC"
  1254. depends on OLPC
  1255. endchoice
  1256. config PCI_BIOS
  1257. def_bool y
  1258. depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
  1259. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1260. config PCI_DIRECT
  1261. def_bool y
  1262. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
  1263. config PCI_MMCONFIG
  1264. def_bool y
  1265. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1266. config PCI_OLPC
  1267. bool
  1268. depends on PCI && PCI_GOOLPC
  1269. default y
  1270. config PCI_DOMAINS
  1271. def_bool y
  1272. depends on PCI
  1273. config PCI_MMCONFIG
  1274. bool "Support mmconfig PCI config space access"
  1275. depends on X86_64 && PCI && ACPI
  1276. config DMAR
  1277. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1278. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1279. help
  1280. DMA remapping (DMAR) devices support enables independent address
  1281. translations for Direct Memory Access (DMA) from devices.
  1282. These DMA remapping devices are reported via ACPI tables
  1283. and include PCI device scope covered by these DMA
  1284. remapping devices.
  1285. config DMAR_GFX_WA
  1286. def_bool y
  1287. prompt "Support for Graphics workaround"
  1288. depends on DMAR
  1289. help
  1290. Current Graphics drivers tend to use physical address
  1291. for DMA and avoid using DMA APIs. Setting this config
  1292. option permits the IOMMU driver to set a unity map for
  1293. all the OS-visible memory. Hence the driver can continue
  1294. to use physical addresses for DMA.
  1295. config DMAR_FLOPPY_WA
  1296. def_bool y
  1297. depends on DMAR
  1298. help
  1299. Floppy disk drivers are know to bypass DMA API calls
  1300. thereby failing to work when IOMMU is enabled. This
  1301. workaround will setup a 1:1 mapping for the first
  1302. 16M to make floppy (an ISA device) work.
  1303. source "drivers/pci/pcie/Kconfig"
  1304. source "drivers/pci/Kconfig"
  1305. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1306. config ISA_DMA_API
  1307. def_bool y
  1308. if X86_32
  1309. config ISA
  1310. bool "ISA support"
  1311. depends on !(X86_VOYAGER || X86_VISWS)
  1312. help
  1313. Find out whether you have ISA slots on your motherboard. ISA is the
  1314. name of a bus system, i.e. the way the CPU talks to the other stuff
  1315. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1316. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1317. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1318. config EISA
  1319. bool "EISA support"
  1320. depends on ISA
  1321. ---help---
  1322. The Extended Industry Standard Architecture (EISA) bus was
  1323. developed as an open alternative to the IBM MicroChannel bus.
  1324. The EISA bus provided some of the features of the IBM MicroChannel
  1325. bus while maintaining backward compatibility with cards made for
  1326. the older ISA bus. The EISA bus saw limited use between 1988 and
  1327. 1995 when it was made obsolete by the PCI bus.
  1328. Say Y here if you are building a kernel for an EISA-based machine.
  1329. Otherwise, say N.
  1330. source "drivers/eisa/Kconfig"
  1331. config MCA
  1332. bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
  1333. default y if X86_VOYAGER
  1334. help
  1335. MicroChannel Architecture is found in some IBM PS/2 machines and
  1336. laptops. It is a bus system similar to PCI or ISA. See
  1337. <file:Documentation/mca.txt> (and especially the web page given
  1338. there) before attempting to build an MCA bus kernel.
  1339. source "drivers/mca/Kconfig"
  1340. config SCx200
  1341. tristate "NatSemi SCx200 support"
  1342. depends on !X86_VOYAGER
  1343. help
  1344. This provides basic support for National Semiconductor's
  1345. (now AMD's) Geode processors. The driver probes for the
  1346. PCI-IDs of several on-chip devices, so its a good dependency
  1347. for other scx200_* drivers.
  1348. If compiled as a module, the driver is named scx200.
  1349. config SCx200HR_TIMER
  1350. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1351. depends on SCx200 && GENERIC_TIME
  1352. default y
  1353. help
  1354. This driver provides a clocksource built upon the on-chip
  1355. 27MHz high-resolution timer. Its also a workaround for
  1356. NSC Geode SC-1100's buggy TSC, which loses time when the
  1357. processor goes idle (as is done by the scheduler). The
  1358. other workaround is idle=poll boot option.
  1359. config GEODE_MFGPT_TIMER
  1360. def_bool y
  1361. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1362. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1363. help
  1364. This driver provides a clock event source based on the MFGPT
  1365. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1366. MFGPTs have a better resolution and max interval than the
  1367. generic PIT, and are suitable for use as high-res timers.
  1368. config OLPC
  1369. bool "One Laptop Per Child support"
  1370. default n
  1371. help
  1372. Add support for detecting the unique features of the OLPC
  1373. XO hardware.
  1374. endif # X86_32
  1375. config K8_NB
  1376. def_bool y
  1377. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1378. source "drivers/pcmcia/Kconfig"
  1379. source "drivers/pci/hotplug/Kconfig"
  1380. endmenu
  1381. menu "Executable file formats / Emulations"
  1382. source "fs/Kconfig.binfmt"
  1383. config IA32_EMULATION
  1384. bool "IA32 Emulation"
  1385. depends on X86_64
  1386. select COMPAT_BINFMT_ELF
  1387. help
  1388. Include code to run 32-bit programs under a 64-bit kernel. You should
  1389. likely turn this on, unless you're 100% sure that you don't have any
  1390. 32-bit programs left.
  1391. config IA32_AOUT
  1392. tristate "IA32 a.out support"
  1393. depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
  1394. help
  1395. Support old a.out binaries in the 32bit emulation.
  1396. config COMPAT
  1397. def_bool y
  1398. depends on IA32_EMULATION
  1399. config COMPAT_FOR_U64_ALIGNMENT
  1400. def_bool COMPAT
  1401. depends on X86_64
  1402. config SYSVIPC_COMPAT
  1403. def_bool y
  1404. depends on X86_64 && COMPAT && SYSVIPC
  1405. endmenu
  1406. source "net/Kconfig"
  1407. source "drivers/Kconfig"
  1408. source "drivers/firmware/Kconfig"
  1409. source "fs/Kconfig"
  1410. source "arch/x86/Kconfig.debug"
  1411. source "security/Kconfig"
  1412. source "crypto/Kconfig"
  1413. source "arch/x86/kvm/Kconfig"
  1414. source "lib/Kconfig"