Kconfig 56 KB

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  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_DYNAMIC_FTRACE
  23. select HAVE_FTRACE
  24. select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
  25. select HAVE_ARCH_KGDB if !X86_VOYAGER
  26. config DEFCONFIG_LIST
  27. string
  28. depends on X86_32
  29. option defconfig_list
  30. default "arch/x86/configs/i386_defconfig"
  31. config DEFCONFIG_LIST
  32. string
  33. depends on X86_64
  34. option defconfig_list
  35. default "arch/x86/configs/x86_64_defconfig"
  36. config GENERIC_LOCKBREAK
  37. def_bool n
  38. config GENERIC_TIME
  39. def_bool y
  40. config GENERIC_CMOS_UPDATE
  41. def_bool y
  42. config CLOCKSOURCE_WATCHDOG
  43. def_bool y
  44. config GENERIC_CLOCKEVENTS
  45. def_bool y
  46. config GENERIC_CLOCKEVENTS_BROADCAST
  47. def_bool y
  48. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  49. config LOCKDEP_SUPPORT
  50. def_bool y
  51. config STACKTRACE_SUPPORT
  52. def_bool y
  53. config HAVE_LATENCYTOP_SUPPORT
  54. def_bool y
  55. config FAST_CMPXCHG_LOCAL
  56. bool
  57. default y
  58. config MMU
  59. def_bool y
  60. config ZONE_DMA
  61. def_bool y
  62. config SBUS
  63. bool
  64. config GENERIC_ISA_DMA
  65. def_bool y
  66. config GENERIC_IOMAP
  67. def_bool y
  68. config GENERIC_BUG
  69. def_bool y
  70. depends on BUG
  71. config GENERIC_HWEIGHT
  72. def_bool y
  73. config GENERIC_GPIO
  74. def_bool n
  75. config ARCH_MAY_HAVE_PC_FDC
  76. def_bool y
  77. config RWSEM_GENERIC_SPINLOCK
  78. def_bool !X86_XADD
  79. config RWSEM_XCHGADD_ALGORITHM
  80. def_bool X86_XADD
  81. config ARCH_HAS_ILOG2_U32
  82. def_bool n
  83. config ARCH_HAS_ILOG2_U64
  84. def_bool n
  85. config ARCH_HAS_CPU_IDLE_WAIT
  86. def_bool y
  87. config GENERIC_CALIBRATE_DELAY
  88. def_bool y
  89. config GENERIC_TIME_VSYSCALL
  90. bool
  91. default X86_64
  92. config ARCH_HAS_CPU_RELAX
  93. def_bool y
  94. config ARCH_HAS_CACHE_LINE_SIZE
  95. def_bool y
  96. config HAVE_SETUP_PER_CPU_AREA
  97. def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
  98. config HAVE_CPUMASK_OF_CPU_MAP
  99. def_bool X86_64_SMP
  100. config ARCH_HIBERNATION_POSSIBLE
  101. def_bool y
  102. depends on !SMP || !X86_VOYAGER
  103. config ARCH_SUSPEND_POSSIBLE
  104. def_bool y
  105. depends on !X86_VOYAGER
  106. config ZONE_DMA32
  107. bool
  108. default X86_64
  109. config ARCH_POPULATES_NODE_MAP
  110. def_bool y
  111. config AUDIT_ARCH
  112. bool
  113. default X86_64
  114. config ARCH_SUPPORTS_AOUT
  115. def_bool y
  116. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  117. def_bool y
  118. # Use the generic interrupt handling code in kernel/irq/:
  119. config GENERIC_HARDIRQS
  120. bool
  121. default y
  122. config GENERIC_IRQ_PROBE
  123. bool
  124. default y
  125. config GENERIC_PENDING_IRQ
  126. bool
  127. depends on GENERIC_HARDIRQS && SMP
  128. default y
  129. config X86_SMP
  130. bool
  131. depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
  132. default y
  133. config X86_32_SMP
  134. def_bool y
  135. depends on X86_32 && SMP
  136. config X86_64_SMP
  137. def_bool y
  138. depends on X86_64 && SMP
  139. config X86_HT
  140. bool
  141. depends on SMP
  142. depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
  143. default y
  144. config X86_BIOS_REBOOT
  145. bool
  146. depends on !X86_VISWS && !X86_VOYAGER
  147. default y
  148. config X86_TRAMPOLINE
  149. bool
  150. depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
  151. default y
  152. config KTIME_SCALAR
  153. def_bool X86_32
  154. source "init/Kconfig"
  155. menu "Processor type and features"
  156. source "kernel/time/Kconfig"
  157. config SMP
  158. bool "Symmetric multi-processing support"
  159. ---help---
  160. This enables support for systems with more than one CPU. If you have
  161. a system with only one CPU, like most personal computers, say N. If
  162. you have a system with more than one CPU, say Y.
  163. If you say N here, the kernel will run on single and multiprocessor
  164. machines, but will use only one CPU of a multiprocessor machine. If
  165. you say Y here, the kernel will run on many, but not all,
  166. singleprocessor machines. On a singleprocessor machine, the kernel
  167. will run faster if you say N here.
  168. Note that if you say Y here and choose architecture "586" or
  169. "Pentium" under "Processor family", the kernel will not work on 486
  170. architectures. Similarly, multiprocessor kernels for the "PPro"
  171. architecture may not work on all Pentium based boards.
  172. People using multiprocessor machines who say Y here should also say
  173. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  174. Management" code will be disabled if you say Y here.
  175. See also <file:Documentation/i386/IO-APIC.txt>,
  176. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  177. <http://www.tldp.org/docs.html#howto>.
  178. If you don't know what to do here, say N.
  179. choice
  180. prompt "Subarchitecture Type"
  181. default X86_PC
  182. config X86_PC
  183. bool "PC-compatible"
  184. help
  185. Choose this option if your computer is a standard PC or compatible.
  186. config X86_ELAN
  187. bool "AMD Elan"
  188. depends on X86_32
  189. help
  190. Select this for an AMD Elan processor.
  191. Do not use this option for K6/Athlon/Opteron processors!
  192. If unsure, choose "PC-compatible" instead.
  193. config X86_VOYAGER
  194. bool "Voyager (NCR)"
  195. depends on X86_32 && (SMP || BROKEN)
  196. help
  197. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  198. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  199. *** WARNING ***
  200. If you do not specifically know you have a Voyager based machine,
  201. say N here, otherwise the kernel you build will not be bootable.
  202. config X86_NUMAQ
  203. bool "NUMAQ (IBM/Sequent)"
  204. depends on SMP && X86_32
  205. select NUMA
  206. help
  207. This option is used for getting Linux to run on a (IBM/Sequent) NUMA
  208. multiquad box. This changes the way that processors are bootstrapped,
  209. and uses Clustered Logical APIC addressing mode instead of Flat Logical.
  210. You will need a new lynxer.elf file to flash your firmware with - send
  211. email to <Martin.Bligh@us.ibm.com>.
  212. config X86_SUMMIT
  213. bool "Summit/EXA (IBM x440)"
  214. depends on X86_32 && SMP
  215. help
  216. This option is needed for IBM systems that use the Summit/EXA chipset.
  217. In particular, it is needed for the x440.
  218. If you don't have one of these computers, you should say N here.
  219. If you want to build a NUMA kernel, you must select ACPI.
  220. config X86_BIGSMP
  221. bool "Support for other sub-arch SMP systems with more than 8 CPUs"
  222. depends on X86_32 && SMP
  223. help
  224. This option is needed for the systems that have more than 8 CPUs
  225. and if the system is not of any sub-arch type above.
  226. If you don't have such a system, you should say N here.
  227. config X86_VISWS
  228. bool "SGI 320/540 (Visual Workstation)"
  229. depends on X86_32
  230. help
  231. The SGI Visual Workstation series is an IA32-based workstation
  232. based on SGI systems chips with some legacy PC hardware attached.
  233. Say Y here to create a kernel to run on the SGI 320 or 540.
  234. A kernel compiled for the Visual Workstation will not run on PCs
  235. and vice versa. See <file:Documentation/sgi-visws.txt> for details.
  236. config X86_GENERICARCH
  237. bool "Generic architecture (Summit, bigsmp, ES7000, default)"
  238. depends on X86_32
  239. help
  240. This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
  241. It is intended for a generic binary kernel.
  242. If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
  243. config X86_ES7000
  244. bool "Support for Unisys ES7000 IA32 series"
  245. depends on X86_32 && SMP
  246. help
  247. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  248. supposed to run on an IA32-based Unisys ES7000 system.
  249. Only choose this option if you have such a system, otherwise you
  250. should say N here.
  251. config X86_RDC321X
  252. bool "RDC R-321x SoC"
  253. depends on X86_32
  254. select M486
  255. select X86_REBOOTFIXUPS
  256. select GENERIC_GPIO
  257. select LEDS_CLASS
  258. select LEDS_GPIO
  259. select NEW_LEDS
  260. help
  261. This option is needed for RDC R-321x system-on-chip, also known
  262. as R-8610-(G).
  263. If you don't have one of these chips, you should say N here.
  264. config X86_VSMP
  265. bool "Support for ScaleMP vSMP"
  266. select PARAVIRT
  267. depends on X86_64
  268. help
  269. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  270. supposed to run on these EM64T-based machines. Only choose this option
  271. if you have one of these machines.
  272. endchoice
  273. config SCHED_NO_NO_OMIT_FRAME_POINTER
  274. def_bool y
  275. prompt "Single-depth WCHAN output"
  276. depends on X86_32
  277. help
  278. Calculate simpler /proc/<PID>/wchan values. If this option
  279. is disabled then wchan values will recurse back to the
  280. caller function. This provides more accurate wchan values,
  281. at the expense of slightly more scheduling overhead.
  282. If in doubt, say "Y".
  283. menuconfig PARAVIRT_GUEST
  284. bool "Paravirtualized guest support"
  285. help
  286. Say Y here to get to see options related to running Linux under
  287. various hypervisors. This option alone does not add any kernel code.
  288. If you say N, all options in this submenu will be skipped and disabled.
  289. if PARAVIRT_GUEST
  290. source "arch/x86/xen/Kconfig"
  291. config VMI
  292. bool "VMI Guest support"
  293. select PARAVIRT
  294. depends on X86_32
  295. depends on !(X86_VISWS || X86_VOYAGER)
  296. help
  297. VMI provides a paravirtualized interface to the VMware ESX server
  298. (it could be used by other hypervisors in theory too, but is not
  299. at the moment), by linking the kernel to a GPL-ed ROM module
  300. provided by the hypervisor.
  301. config KVM_CLOCK
  302. bool "KVM paravirtualized clock"
  303. select PARAVIRT
  304. depends on !(X86_VISWS || X86_VOYAGER)
  305. help
  306. Turning on this option will allow you to run a paravirtualized clock
  307. when running over the KVM hypervisor. Instead of relying on a PIT
  308. (or probably other) emulation by the underlying device model, the host
  309. provides the guest with timing infrastructure such as time of day, and
  310. system time
  311. config KVM_GUEST
  312. bool "KVM Guest support"
  313. select PARAVIRT
  314. depends on !(X86_VISWS || X86_VOYAGER)
  315. help
  316. This option enables various optimizations for running under the KVM
  317. hypervisor.
  318. source "arch/x86/lguest/Kconfig"
  319. config PARAVIRT
  320. bool "Enable paravirtualization code"
  321. depends on !(X86_VISWS || X86_VOYAGER)
  322. help
  323. This changes the kernel so it can modify itself when it is run
  324. under a hypervisor, potentially improving performance significantly
  325. over full virtualization. However, when run without a hypervisor
  326. the kernel is theoretically slower and slightly larger.
  327. endif
  328. config MEMTEST_BOOTPARAM
  329. bool "Memtest boot parameter"
  330. depends on X86_64
  331. default y
  332. help
  333. This option adds a kernel parameter 'memtest', which allows memtest
  334. to be disabled at boot. If this option is selected, memtest
  335. functionality can be disabled with memtest=0 on the kernel
  336. command line. The purpose of this option is to allow a single
  337. kernel image to be distributed with memtest built in, but not
  338. necessarily enabled.
  339. If you are unsure how to answer this question, answer Y.
  340. config MEMTEST_BOOTPARAM_VALUE
  341. int "Memtest boot parameter default value (0-4)"
  342. depends on MEMTEST_BOOTPARAM
  343. range 0 4
  344. default 0
  345. help
  346. This option sets the default value for the kernel parameter
  347. 'memtest', which allows memtest to be disabled at boot. If this
  348. option is set to 0 (zero), the memtest kernel parameter will
  349. default to 0, disabling memtest at bootup. If this option is
  350. set to 4, the memtest kernel parameter will default to 4,
  351. enabling memtest at bootup, and use that as pattern number.
  352. If you are unsure how to answer this question, answer 0.
  353. config ACPI_SRAT
  354. def_bool y
  355. depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  356. select ACPI_NUMA
  357. config HAVE_ARCH_PARSE_SRAT
  358. def_bool y
  359. depends on ACPI_SRAT
  360. config X86_SUMMIT_NUMA
  361. def_bool y
  362. depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  363. config X86_CYCLONE_TIMER
  364. def_bool y
  365. depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
  366. config ES7000_CLUSTERED_APIC
  367. def_bool y
  368. depends on SMP && X86_ES7000 && MPENTIUMIII
  369. source "arch/x86/Kconfig.cpu"
  370. config HPET_TIMER
  371. def_bool X86_64
  372. prompt "HPET Timer Support" if X86_32
  373. help
  374. Use the IA-PC HPET (High Precision Event Timer) to manage
  375. time in preference to the PIT and RTC, if a HPET is
  376. present.
  377. HPET is the next generation timer replacing legacy 8254s.
  378. The HPET provides a stable time base on SMP
  379. systems, unlike the TSC, but it is more expensive to access,
  380. as it is off-chip. You can find the HPET spec at
  381. <http://www.intel.com/hardwaredesign/hpetspec.htm>.
  382. You can safely choose Y here. However, HPET will only be
  383. activated if the platform and the BIOS support this feature.
  384. Otherwise the 8254 will be used for timing services.
  385. Choose N to continue using the legacy 8254 timer.
  386. config HPET_EMULATE_RTC
  387. def_bool y
  388. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  389. # Mark as embedded because too many people got it wrong.
  390. # The code disables itself when not needed.
  391. config DMI
  392. default y
  393. bool "Enable DMI scanning" if EMBEDDED
  394. help
  395. Enabled scanning of DMI to identify machine quirks. Say Y
  396. here unless you have verified that your setup is not
  397. affected by entries in the DMI blacklist. Required by PNP
  398. BIOS code.
  399. config GART_IOMMU
  400. bool "GART IOMMU support" if EMBEDDED
  401. default y
  402. select SWIOTLB
  403. select AGP
  404. depends on X86_64 && PCI
  405. help
  406. Support for full DMA access of devices with 32bit memory access only
  407. on systems with more than 3GB. This is usually needed for USB,
  408. sound, many IDE/SATA chipsets and some other devices.
  409. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  410. based hardware IOMMU and a software bounce buffer based IOMMU used
  411. on Intel systems and as fallback.
  412. The code is only active when needed (enough memory and limited
  413. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  414. too.
  415. config CALGARY_IOMMU
  416. bool "IBM Calgary IOMMU support"
  417. select SWIOTLB
  418. depends on X86_64 && PCI && EXPERIMENTAL
  419. help
  420. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  421. systems. Needed to run systems with more than 3GB of memory
  422. properly with 32-bit PCI devices that do not support DAC
  423. (Double Address Cycle). Calgary also supports bus level
  424. isolation, where all DMAs pass through the IOMMU. This
  425. prevents them from going anywhere except their intended
  426. destination. This catches hard-to-find kernel bugs and
  427. mis-behaving drivers and devices that do not use the DMA-API
  428. properly to set up their DMA buffers. The IOMMU can be
  429. turned off at boot time with the iommu=off parameter.
  430. Normally the kernel will make the right choice by itself.
  431. If unsure, say Y.
  432. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  433. def_bool y
  434. prompt "Should Calgary be enabled by default?"
  435. depends on CALGARY_IOMMU
  436. help
  437. Should Calgary be enabled by default? if you choose 'y', Calgary
  438. will be used (if it exists). If you choose 'n', Calgary will not be
  439. used even if it exists. If you choose 'n' and would like to use
  440. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  441. If unsure, say Y.
  442. # need this always selected by IOMMU for the VIA workaround
  443. config SWIOTLB
  444. bool
  445. help
  446. Support for software bounce buffers used on x86-64 systems
  447. which don't have a hardware IOMMU (e.g. the current generation
  448. of Intel's x86-64 CPUs). Using this PCI devices which can only
  449. access 32-bits of memory can be used on systems with more than
  450. 3 GB of memory. If unsure, say Y.
  451. config IOMMU_HELPER
  452. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
  453. config NR_CPUS
  454. int "Maximum number of CPUs (2-255)"
  455. range 2 255
  456. depends on SMP
  457. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  458. default "8"
  459. help
  460. This allows you to specify the maximum number of CPUs which this
  461. kernel will support. The maximum supported value is 255 and the
  462. minimum value which makes sense is 2.
  463. This is purely to save memory - each supported CPU adds
  464. approximately eight kilobytes to the kernel image.
  465. config SCHED_SMT
  466. bool "SMT (Hyperthreading) scheduler support"
  467. depends on X86_HT
  468. help
  469. SMT scheduler support improves the CPU scheduler's decision making
  470. when dealing with Intel Pentium 4 chips with HyperThreading at a
  471. cost of slightly increased overhead in some places. If unsure say
  472. N here.
  473. config SCHED_MC
  474. def_bool y
  475. prompt "Multi-core scheduler support"
  476. depends on X86_HT
  477. help
  478. Multi-core scheduler support improves the CPU scheduler's decision
  479. making when dealing with multi-core CPU chips at a cost of slightly
  480. increased overhead in some places. If unsure say N here.
  481. source "kernel/Kconfig.preempt"
  482. config X86_UP_APIC
  483. bool "Local APIC support on uniprocessors"
  484. depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
  485. help
  486. A local APIC (Advanced Programmable Interrupt Controller) is an
  487. integrated interrupt controller in the CPU. If you have a single-CPU
  488. system which has a processor with a local APIC, you can say Y here to
  489. enable and use it. If you say Y here even though your machine doesn't
  490. have a local APIC, then the kernel will still run with no slowdown at
  491. all. The local APIC supports CPU-generated self-interrupts (timer,
  492. performance counters), and the NMI watchdog which detects hard
  493. lockups.
  494. config X86_UP_IOAPIC
  495. bool "IO-APIC support on uniprocessors"
  496. depends on X86_UP_APIC
  497. help
  498. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  499. SMP-capable replacement for PC-style interrupt controllers. Most
  500. SMP systems and many recent uniprocessor systems have one.
  501. If you have a single-CPU system with an IO-APIC, you can say Y here
  502. to use it. If you say Y here even though your machine doesn't have
  503. an IO-APIC, then the kernel will still run with no slowdown at all.
  504. config X86_LOCAL_APIC
  505. def_bool y
  506. depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
  507. config X86_IO_APIC
  508. def_bool y
  509. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
  510. config X86_VISWS_APIC
  511. def_bool y
  512. depends on X86_32 && X86_VISWS
  513. config X86_MCE
  514. bool "Machine Check Exception"
  515. depends on !X86_VOYAGER
  516. ---help---
  517. Machine Check Exception support allows the processor to notify the
  518. kernel if it detects a problem (e.g. overheating, component failure).
  519. The action the kernel takes depends on the severity of the problem,
  520. ranging from a warning message on the console, to halting the machine.
  521. Your processor must be a Pentium or newer to support this - check the
  522. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  523. have a design flaw which leads to false MCE events - hence MCE is
  524. disabled on all P5 processors, unless explicitly enabled with "mce"
  525. as a boot argument. Similarly, if MCE is built in and creates a
  526. problem on some new non-standard machine, you can boot with "nomce"
  527. to disable it. MCE support simply ignores non-MCE processors like
  528. the 386 and 486, so nearly everyone can say Y here.
  529. config X86_MCE_INTEL
  530. def_bool y
  531. prompt "Intel MCE features"
  532. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  533. help
  534. Additional support for intel specific MCE features such as
  535. the thermal monitor.
  536. config X86_MCE_AMD
  537. def_bool y
  538. prompt "AMD MCE features"
  539. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  540. help
  541. Additional support for AMD specific MCE features such as
  542. the DRAM Error Threshold.
  543. config X86_MCE_NONFATAL
  544. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  545. depends on X86_32 && X86_MCE
  546. help
  547. Enabling this feature starts a timer that triggers every 5 seconds which
  548. will look at the machine check registers to see if anything happened.
  549. Non-fatal problems automatically get corrected (but still logged).
  550. Disable this if you don't want to see these messages.
  551. Seeing the messages this option prints out may be indicative of dying
  552. or out-of-spec (ie, overclocked) hardware.
  553. This option only does something on certain CPUs.
  554. (AMD Athlon/Duron and Intel Pentium 4)
  555. config X86_MCE_P4THERMAL
  556. bool "check for P4 thermal throttling interrupt."
  557. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
  558. help
  559. Enabling this feature will cause a message to be printed when the P4
  560. enters thermal throttling.
  561. config VM86
  562. bool "Enable VM86 support" if EMBEDDED
  563. default y
  564. depends on X86_32
  565. help
  566. This option is required by programs like DOSEMU to run 16-bit legacy
  567. code on X86 processors. It also may be needed by software like
  568. XFree86 to initialize some video cards via BIOS. Disabling this
  569. option saves about 6k.
  570. config TOSHIBA
  571. tristate "Toshiba Laptop support"
  572. depends on X86_32
  573. ---help---
  574. This adds a driver to safely access the System Management Mode of
  575. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  576. not work on models with a Phoenix BIOS. The System Management Mode
  577. is used to set the BIOS and power saving options on Toshiba portables.
  578. For information on utilities to make use of this driver see the
  579. Toshiba Linux utilities web site at:
  580. <http://www.buzzard.org.uk/toshiba/>.
  581. Say Y if you intend to run this kernel on a Toshiba portable.
  582. Say N otherwise.
  583. config I8K
  584. tristate "Dell laptop support"
  585. ---help---
  586. This adds a driver to safely access the System Management Mode
  587. of the CPU on the Dell Inspiron 8000. The System Management Mode
  588. is used to read cpu temperature and cooling fan status and to
  589. control the fans on the I8K portables.
  590. This driver has been tested only on the Inspiron 8000 but it may
  591. also work with other Dell laptops. You can force loading on other
  592. models by passing the parameter `force=1' to the module. Use at
  593. your own risk.
  594. For information on utilities to make use of this driver see the
  595. I8K Linux utilities web site at:
  596. <http://people.debian.org/~dz/i8k/>
  597. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  598. Say N otherwise.
  599. config X86_REBOOTFIXUPS
  600. def_bool n
  601. prompt "Enable X86 board specific fixups for reboot"
  602. depends on X86_32 && X86
  603. ---help---
  604. This enables chipset and/or board specific fixups to be done
  605. in order to get reboot to work correctly. This is only needed on
  606. some combinations of hardware and BIOS. The symptom, for which
  607. this config is intended, is when reboot ends with a stalled/hung
  608. system.
  609. Currently, the only fixup is for the Geode machines using
  610. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  611. Say Y if you want to enable the fixup. Currently, it's safe to
  612. enable this option even if you don't need it.
  613. Say N otherwise.
  614. config MICROCODE
  615. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  616. select FW_LOADER
  617. ---help---
  618. If you say Y here, you will be able to update the microcode on
  619. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  620. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  621. actual microcode binary data itself which is not shipped with the
  622. Linux kernel.
  623. For latest news and information on obtaining all the required
  624. ingredients for this driver, check:
  625. <http://www.urbanmyth.org/microcode/>.
  626. To compile this driver as a module, choose M here: the
  627. module will be called microcode.
  628. config MICROCODE_OLD_INTERFACE
  629. def_bool y
  630. depends on MICROCODE
  631. config X86_MSR
  632. tristate "/dev/cpu/*/msr - Model-specific register support"
  633. help
  634. This device gives privileged processes access to the x86
  635. Model-Specific Registers (MSRs). It is a character device with
  636. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  637. MSR accesses are directed to a specific CPU on multi-processor
  638. systems.
  639. config X86_CPUID
  640. tristate "/dev/cpu/*/cpuid - CPU information support"
  641. help
  642. This device gives processes access to the x86 CPUID instruction to
  643. be executed on a specific processor. It is a character device
  644. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  645. /dev/cpu/31/cpuid.
  646. choice
  647. prompt "High Memory Support"
  648. default HIGHMEM4G if !X86_NUMAQ
  649. default HIGHMEM64G if X86_NUMAQ
  650. depends on X86_32
  651. config NOHIGHMEM
  652. bool "off"
  653. depends on !X86_NUMAQ
  654. ---help---
  655. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  656. However, the address space of 32-bit x86 processors is only 4
  657. Gigabytes large. That means that, if you have a large amount of
  658. physical memory, not all of it can be "permanently mapped" by the
  659. kernel. The physical memory that's not permanently mapped is called
  660. "high memory".
  661. If you are compiling a kernel which will never run on a machine with
  662. more than 1 Gigabyte total physical RAM, answer "off" here (default
  663. choice and suitable for most users). This will result in a "3GB/1GB"
  664. split: 3GB are mapped so that each process sees a 3GB virtual memory
  665. space and the remaining part of the 4GB virtual memory space is used
  666. by the kernel to permanently map as much physical memory as
  667. possible.
  668. If the machine has between 1 and 4 Gigabytes physical RAM, then
  669. answer "4GB" here.
  670. If more than 4 Gigabytes is used then answer "64GB" here. This
  671. selection turns Intel PAE (Physical Address Extension) mode on.
  672. PAE implements 3-level paging on IA32 processors. PAE is fully
  673. supported by Linux, PAE mode is implemented on all recent Intel
  674. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  675. then the kernel will not boot on CPUs that don't support PAE!
  676. The actual amount of total physical memory will either be
  677. auto detected or can be forced by using a kernel command line option
  678. such as "mem=256M". (Try "man bootparam" or see the documentation of
  679. your boot loader (lilo or loadlin) about how to pass options to the
  680. kernel at boot time.)
  681. If unsure, say "off".
  682. config HIGHMEM4G
  683. bool "4GB"
  684. depends on !X86_NUMAQ
  685. help
  686. Select this if you have a 32-bit processor and between 1 and 4
  687. gigabytes of physical RAM.
  688. config HIGHMEM64G
  689. bool "64GB"
  690. depends on !M386 && !M486
  691. select X86_PAE
  692. help
  693. Select this if you have a 32-bit processor and more than 4
  694. gigabytes of physical RAM.
  695. endchoice
  696. choice
  697. depends on EXPERIMENTAL
  698. prompt "Memory split" if EMBEDDED
  699. default VMSPLIT_3G
  700. depends on X86_32
  701. help
  702. Select the desired split between kernel and user memory.
  703. If the address range available to the kernel is less than the
  704. physical memory installed, the remaining memory will be available
  705. as "high memory". Accessing high memory is a little more costly
  706. than low memory, as it needs to be mapped into the kernel first.
  707. Note that increasing the kernel address space limits the range
  708. available to user programs, making the address space there
  709. tighter. Selecting anything other than the default 3G/1G split
  710. will also likely make your kernel incompatible with binary-only
  711. kernel modules.
  712. If you are not absolutely sure what you are doing, leave this
  713. option alone!
  714. config VMSPLIT_3G
  715. bool "3G/1G user/kernel split"
  716. config VMSPLIT_3G_OPT
  717. depends on !X86_PAE
  718. bool "3G/1G user/kernel split (for full 1G low memory)"
  719. config VMSPLIT_2G
  720. bool "2G/2G user/kernel split"
  721. config VMSPLIT_2G_OPT
  722. depends on !X86_PAE
  723. bool "2G/2G user/kernel split (for full 2G low memory)"
  724. config VMSPLIT_1G
  725. bool "1G/3G user/kernel split"
  726. endchoice
  727. config PAGE_OFFSET
  728. hex
  729. default 0xB0000000 if VMSPLIT_3G_OPT
  730. default 0x80000000 if VMSPLIT_2G
  731. default 0x78000000 if VMSPLIT_2G_OPT
  732. default 0x40000000 if VMSPLIT_1G
  733. default 0xC0000000
  734. depends on X86_32
  735. config HIGHMEM
  736. def_bool y
  737. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  738. config X86_PAE
  739. def_bool n
  740. prompt "PAE (Physical Address Extension) Support"
  741. depends on X86_32 && !HIGHMEM4G
  742. select RESOURCES_64BIT
  743. help
  744. PAE is required for NX support, and furthermore enables
  745. larger swapspace support for non-overcommit purposes. It
  746. has the cost of more pagetable lookup overhead, and also
  747. consumes more pagetable space per process.
  748. # Common NUMA Features
  749. config NUMA
  750. bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
  751. depends on SMP
  752. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
  753. default n if X86_PC
  754. default y if (X86_NUMAQ || X86_SUMMIT)
  755. help
  756. Enable NUMA (Non Uniform Memory Access) support.
  757. The kernel will try to allocate memory used by a CPU on the
  758. local memory controller of the CPU and add some more
  759. NUMA awareness to the kernel.
  760. For i386 this is currently highly experimental and should be only
  761. used for kernel development. It might also cause boot failures.
  762. For x86_64 this is recommended on all multiprocessor Opteron systems.
  763. If the system is EM64T, you should say N unless your system is
  764. EM64T NUMA.
  765. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  766. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  767. config K8_NUMA
  768. def_bool y
  769. prompt "Old style AMD Opteron NUMA detection"
  770. depends on X86_64 && NUMA && PCI
  771. help
  772. Enable K8 NUMA node topology detection. You should say Y here if
  773. you have a multi processor AMD K8 system. This uses an old
  774. method to read the NUMA configuration directly from the builtin
  775. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  776. instead, which also takes priority if both are compiled in.
  777. config X86_64_ACPI_NUMA
  778. def_bool y
  779. prompt "ACPI NUMA detection"
  780. depends on X86_64 && NUMA && ACPI && PCI
  781. select ACPI_NUMA
  782. help
  783. Enable ACPI SRAT based node topology detection.
  784. # Some NUMA nodes have memory ranges that span
  785. # other nodes. Even though a pfn is valid and
  786. # between a node's start and end pfns, it may not
  787. # reside on that node. See memmap_init_zone()
  788. # for details.
  789. config NODES_SPAN_OTHER_NODES
  790. def_bool y
  791. depends on X86_64_ACPI_NUMA
  792. config NUMA_EMU
  793. bool "NUMA emulation"
  794. depends on X86_64 && NUMA
  795. help
  796. Enable NUMA emulation. A flat machine will be split
  797. into virtual nodes when booted with "numa=fake=N", where N is the
  798. number of nodes. This is only useful for debugging.
  799. config NODES_SHIFT
  800. int "Max num nodes shift(1-15)"
  801. range 1 15 if X86_64
  802. default "6" if X86_64
  803. default "4" if X86_NUMAQ
  804. default "3"
  805. depends on NEED_MULTIPLE_NODES
  806. config HAVE_ARCH_BOOTMEM_NODE
  807. def_bool y
  808. depends on X86_32 && NUMA
  809. config ARCH_HAVE_MEMORY_PRESENT
  810. def_bool y
  811. depends on X86_32 && DISCONTIGMEM
  812. config NEED_NODE_MEMMAP_SIZE
  813. def_bool y
  814. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  815. config HAVE_ARCH_ALLOC_REMAP
  816. def_bool y
  817. depends on X86_32 && NUMA
  818. config ARCH_FLATMEM_ENABLE
  819. def_bool y
  820. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
  821. config ARCH_DISCONTIGMEM_ENABLE
  822. def_bool y
  823. depends on NUMA && X86_32
  824. config ARCH_DISCONTIGMEM_DEFAULT
  825. def_bool y
  826. depends on NUMA && X86_32
  827. config ARCH_SPARSEMEM_DEFAULT
  828. def_bool y
  829. depends on X86_64
  830. config ARCH_SPARSEMEM_ENABLE
  831. def_bool y
  832. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
  833. select SPARSEMEM_STATIC if X86_32
  834. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  835. config ARCH_SELECT_MEMORY_MODEL
  836. def_bool y
  837. depends on ARCH_SPARSEMEM_ENABLE
  838. config ARCH_MEMORY_PROBE
  839. def_bool X86_64
  840. depends on MEMORY_HOTPLUG
  841. source "mm/Kconfig"
  842. config HIGHPTE
  843. bool "Allocate 3rd-level pagetables from highmem"
  844. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  845. help
  846. The VM uses one page table entry for each page of physical memory.
  847. For systems with a lot of RAM, this can be wasteful of precious
  848. low memory. Setting this option will put user-space page table
  849. entries in high memory.
  850. config MATH_EMULATION
  851. bool
  852. prompt "Math emulation" if X86_32
  853. ---help---
  854. Linux can emulate a math coprocessor (used for floating point
  855. operations) if you don't have one. 486DX and Pentium processors have
  856. a math coprocessor built in, 486SX and 386 do not, unless you added
  857. a 487DX or 387, respectively. (The messages during boot time can
  858. give you some hints here ["man dmesg"].) Everyone needs either a
  859. coprocessor or this emulation.
  860. If you don't have a math coprocessor, you need to say Y here; if you
  861. say Y here even though you have a coprocessor, the coprocessor will
  862. be used nevertheless. (This behavior can be changed with the kernel
  863. command line option "no387", which comes handy if your coprocessor
  864. is broken. Try "man bootparam" or see the documentation of your boot
  865. loader (lilo or loadlin) about how to pass options to the kernel at
  866. boot time.) This means that it is a good idea to say Y here if you
  867. intend to use this kernel on different machines.
  868. More information about the internals of the Linux math coprocessor
  869. emulation can be found in <file:arch/x86/math-emu/README>.
  870. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  871. kernel, it won't hurt.
  872. config MTRR
  873. bool "MTRR (Memory Type Range Register) support"
  874. ---help---
  875. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  876. the Memory Type Range Registers (MTRRs) may be used to control
  877. processor access to memory ranges. This is most useful if you have
  878. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  879. allows bus write transfers to be combined into a larger transfer
  880. before bursting over the PCI/AGP bus. This can increase performance
  881. of image write operations 2.5 times or more. Saying Y here creates a
  882. /proc/mtrr file which may be used to manipulate your processor's
  883. MTRRs. Typically the X server should use this.
  884. This code has a reasonably generic interface so that similar
  885. control registers on other processors can be easily supported
  886. as well:
  887. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  888. Registers (ARRs) which provide a similar functionality to MTRRs. For
  889. these, the ARRs are used to emulate the MTRRs.
  890. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  891. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  892. write-combining. All of these processors are supported by this code
  893. and it makes sense to say Y here if you have one of them.
  894. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  895. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  896. can lead to all sorts of problems, so it's good to say Y here.
  897. You can safely say Y even if your machine doesn't have MTRRs, you'll
  898. just add about 9 KB to your kernel.
  899. See <file:Documentation/mtrr.txt> for more information.
  900. config X86_PAT
  901. bool
  902. prompt "x86 PAT support"
  903. depends on MTRR
  904. help
  905. Use PAT attributes to setup page level cache control.
  906. PATs are the modern equivalents of MTRRs and are much more
  907. flexible than MTRRs.
  908. Say N here if you see bootup problems (boot crash, boot hang,
  909. spontaneous reboots) or a non-working video driver.
  910. If unsure, say Y.
  911. config EFI
  912. def_bool n
  913. prompt "EFI runtime service support"
  914. depends on ACPI
  915. ---help---
  916. This enables the kernel to use EFI runtime services that are
  917. available (such as the EFI variable services).
  918. This option is only useful on systems that have EFI firmware.
  919. In addition, you should use the latest ELILO loader available
  920. at <http://elilo.sourceforge.net> in order to take advantage
  921. of EFI runtime services. However, even with this option, the
  922. resultant kernel should continue to boot on existing non-EFI
  923. platforms.
  924. config IRQBALANCE
  925. def_bool y
  926. prompt "Enable kernel irq balancing"
  927. depends on X86_32 && SMP && X86_IO_APIC
  928. help
  929. The default yes will allow the kernel to do irq load balancing.
  930. Saying no will keep the kernel from doing irq load balancing.
  931. config SECCOMP
  932. def_bool y
  933. prompt "Enable seccomp to safely compute untrusted bytecode"
  934. depends on PROC_FS
  935. help
  936. This kernel feature is useful for number crunching applications
  937. that may need to compute untrusted bytecode during their
  938. execution. By using pipes or other transports made available to
  939. the process as file descriptors supporting the read/write
  940. syscalls, it's possible to isolate those applications in
  941. their own address space using seccomp. Once seccomp is
  942. enabled via /proc/<pid>/seccomp, it cannot be disabled
  943. and the task is only allowed to execute a few safe syscalls
  944. defined by each seccomp mode.
  945. If unsure, say Y. Only embedded should say N here.
  946. config CC_STACKPROTECTOR
  947. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  948. depends on X86_64 && EXPERIMENTAL && BROKEN
  949. help
  950. This option turns on the -fstack-protector GCC feature. This
  951. feature puts, at the beginning of critical functions, a canary
  952. value on the stack just before the return address, and validates
  953. the value just before actually returning. Stack based buffer
  954. overflows (that need to overwrite this return address) now also
  955. overwrite the canary, which gets detected and the attack is then
  956. neutralized via a kernel panic.
  957. This feature requires gcc version 4.2 or above, or a distribution
  958. gcc with the feature backported. Older versions are automatically
  959. detected and for those versions, this configuration option is ignored.
  960. config CC_STACKPROTECTOR_ALL
  961. bool "Use stack-protector for all functions"
  962. depends on CC_STACKPROTECTOR
  963. help
  964. Normally, GCC only inserts the canary value protection for
  965. functions that use large-ish on-stack buffers. By enabling
  966. this option, GCC will be asked to do this for ALL functions.
  967. source kernel/Kconfig.hz
  968. config KEXEC
  969. bool "kexec system call"
  970. depends on X86_BIOS_REBOOT
  971. help
  972. kexec is a system call that implements the ability to shutdown your
  973. current kernel, and to start another kernel. It is like a reboot
  974. but it is independent of the system firmware. And like a reboot
  975. you can start any kernel with it, not just Linux.
  976. The name comes from the similarity to the exec system call.
  977. It is an ongoing process to be certain the hardware in a machine
  978. is properly shutdown, so do not be surprised if this code does not
  979. initially work for you. It may help to enable device hotplugging
  980. support. As of this writing the exact hardware interface is
  981. strongly in flux, so no good recommendation can be made.
  982. config CRASH_DUMP
  983. bool "kernel crash dumps (EXPERIMENTAL)"
  984. depends on EXPERIMENTAL
  985. depends on X86_64 || (X86_32 && HIGHMEM)
  986. help
  987. Generate crash dump after being started by kexec.
  988. This should be normally only set in special crash dump kernels
  989. which are loaded in the main kernel with kexec-tools into
  990. a specially reserved region and then later executed after
  991. a crash by kdump/kexec. The crash dump kernel must be compiled
  992. to a memory address not used by the main kernel or BIOS using
  993. PHYSICAL_START, or it must be built as a relocatable image
  994. (CONFIG_RELOCATABLE=y).
  995. For more details see Documentation/kdump/kdump.txt
  996. config PHYSICAL_START
  997. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  998. default "0x1000000" if X86_NUMAQ
  999. default "0x200000" if X86_64
  1000. default "0x100000"
  1001. help
  1002. This gives the physical address where the kernel is loaded.
  1003. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1004. bzImage will decompress itself to above physical address and
  1005. run from there. Otherwise, bzImage will run from the address where
  1006. it has been loaded by the boot loader and will ignore above physical
  1007. address.
  1008. In normal kdump cases one does not have to set/change this option
  1009. as now bzImage can be compiled as a completely relocatable image
  1010. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1011. address. This option is mainly useful for the folks who don't want
  1012. to use a bzImage for capturing the crash dump and want to use a
  1013. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1014. to be specifically compiled to run from a specific memory area
  1015. (normally a reserved region) and this option comes handy.
  1016. So if you are using bzImage for capturing the crash dump, leave
  1017. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  1018. Otherwise if you plan to use vmlinux for capturing the crash dump
  1019. change this value to start of the reserved region (Typically 16MB
  1020. 0x1000000). In other words, it can be set based on the "X" value as
  1021. specified in the "crashkernel=YM@XM" command line boot parameter
  1022. passed to the panic-ed kernel. Typically this parameter is set as
  1023. crashkernel=64M@16M. Please take a look at
  1024. Documentation/kdump/kdump.txt for more details about crash dumps.
  1025. Usage of bzImage for capturing the crash dump is recommended as
  1026. one does not have to build two kernels. Same kernel can be used
  1027. as production kernel and capture kernel. Above option should have
  1028. gone away after relocatable bzImage support is introduced. But it
  1029. is present because there are users out there who continue to use
  1030. vmlinux for dump capture. This option should go away down the
  1031. line.
  1032. Don't change this unless you know what you are doing.
  1033. config RELOCATABLE
  1034. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1035. depends on EXPERIMENTAL
  1036. help
  1037. This builds a kernel image that retains relocation information
  1038. so it can be loaded someplace besides the default 1MB.
  1039. The relocations tend to make the kernel binary about 10% larger,
  1040. but are discarded at runtime.
  1041. One use is for the kexec on panic case where the recovery kernel
  1042. must live at a different physical address than the primary
  1043. kernel.
  1044. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1045. it has been loaded at and the compile time physical address
  1046. (CONFIG_PHYSICAL_START) is ignored.
  1047. config PHYSICAL_ALIGN
  1048. hex
  1049. prompt "Alignment value to which kernel should be aligned" if X86_32
  1050. default "0x100000" if X86_32
  1051. default "0x200000" if X86_64
  1052. range 0x2000 0x400000
  1053. help
  1054. This value puts the alignment restrictions on physical address
  1055. where kernel is loaded and run from. Kernel is compiled for an
  1056. address which meets above alignment restriction.
  1057. If bootloader loads the kernel at a non-aligned address and
  1058. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1059. address aligned to above value and run from there.
  1060. If bootloader loads the kernel at a non-aligned address and
  1061. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1062. load address and decompress itself to the address it has been
  1063. compiled for and run from there. The address for which kernel is
  1064. compiled already meets above alignment restrictions. Hence the
  1065. end result is that kernel runs from a physical address meeting
  1066. above alignment restrictions.
  1067. Don't change this unless you know what you are doing.
  1068. config HOTPLUG_CPU
  1069. bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
  1070. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  1071. ---help---
  1072. Say Y here to experiment with turning CPUs off and on, and to
  1073. enable suspend on SMP systems. CPUs can be controlled through
  1074. /sys/devices/system/cpu.
  1075. Say N if you want to disable CPU hotplug and don't need to
  1076. suspend.
  1077. config COMPAT_VDSO
  1078. def_bool y
  1079. prompt "Compat VDSO support"
  1080. depends on X86_32 || IA32_EMULATION
  1081. help
  1082. Map the 32-bit VDSO to the predictable old-style address too.
  1083. ---help---
  1084. Say N here if you are running a sufficiently recent glibc
  1085. version (2.3.3 or later), to remove the high-mapped
  1086. VDSO mapping and to exclusively use the randomized VDSO.
  1087. If unsure, say Y.
  1088. endmenu
  1089. config ARCH_ENABLE_MEMORY_HOTPLUG
  1090. def_bool y
  1091. depends on X86_64 || (X86_32 && HIGHMEM)
  1092. config HAVE_ARCH_EARLY_PFN_TO_NID
  1093. def_bool X86_64
  1094. depends on NUMA
  1095. menu "Power management options"
  1096. depends on !X86_VOYAGER
  1097. config ARCH_HIBERNATION_HEADER
  1098. def_bool y
  1099. depends on X86_64 && HIBERNATION
  1100. source "kernel/power/Kconfig"
  1101. source "drivers/acpi/Kconfig"
  1102. config X86_APM_BOOT
  1103. bool
  1104. default y
  1105. depends on APM || APM_MODULE
  1106. menuconfig APM
  1107. tristate "APM (Advanced Power Management) BIOS support"
  1108. depends on X86_32 && PM_SLEEP && !X86_VISWS
  1109. ---help---
  1110. APM is a BIOS specification for saving power using several different
  1111. techniques. This is mostly useful for battery powered laptops with
  1112. APM compliant BIOSes. If you say Y here, the system time will be
  1113. reset after a RESUME operation, the /proc/apm device will provide
  1114. battery status information, and user-space programs will receive
  1115. notification of APM "events" (e.g. battery status change).
  1116. If you select "Y" here, you can disable actual use of the APM
  1117. BIOS by passing the "apm=off" option to the kernel at boot time.
  1118. Note that the APM support is almost completely disabled for
  1119. machines with more than one CPU.
  1120. In order to use APM, you will need supporting software. For location
  1121. and more information, read <file:Documentation/power/pm.txt> and the
  1122. Battery Powered Linux mini-HOWTO, available from
  1123. <http://www.tldp.org/docs.html#howto>.
  1124. This driver does not spin down disk drives (see the hdparm(8)
  1125. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1126. VESA-compliant "green" monitors.
  1127. This driver does not support the TI 4000M TravelMate and the ACER
  1128. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1129. desktop machines also don't have compliant BIOSes, and this driver
  1130. may cause those machines to panic during the boot phase.
  1131. Generally, if you don't have a battery in your machine, there isn't
  1132. much point in using this driver and you should say N. If you get
  1133. random kernel OOPSes or reboots that don't seem to be related to
  1134. anything, try disabling/enabling this option (or disabling/enabling
  1135. APM in your BIOS).
  1136. Some other things you should try when experiencing seemingly random,
  1137. "weird" problems:
  1138. 1) make sure that you have enough swap space and that it is
  1139. enabled.
  1140. 2) pass the "no-hlt" option to the kernel
  1141. 3) switch on floating point emulation in the kernel and pass
  1142. the "no387" option to the kernel
  1143. 4) pass the "floppy=nodma" option to the kernel
  1144. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1145. all but the first 4 MB of RAM)
  1146. 6) make sure that the CPU is not over clocked.
  1147. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1148. 8) disable the cache from your BIOS settings
  1149. 9) install a fan for the video card or exchange video RAM
  1150. 10) install a better fan for the CPU
  1151. 11) exchange RAM chips
  1152. 12) exchange the motherboard.
  1153. To compile this driver as a module, choose M here: the
  1154. module will be called apm.
  1155. if APM
  1156. config APM_IGNORE_USER_SUSPEND
  1157. bool "Ignore USER SUSPEND"
  1158. help
  1159. This option will ignore USER SUSPEND requests. On machines with a
  1160. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1161. series notebooks, it is necessary to say Y because of a BIOS bug.
  1162. config APM_DO_ENABLE
  1163. bool "Enable PM at boot time"
  1164. ---help---
  1165. Enable APM features at boot time. From page 36 of the APM BIOS
  1166. specification: "When disabled, the APM BIOS does not automatically
  1167. power manage devices, enter the Standby State, enter the Suspend
  1168. State, or take power saving steps in response to CPU Idle calls."
  1169. This driver will make CPU Idle calls when Linux is idle (unless this
  1170. feature is turned off -- see "Do CPU IDLE calls", below). This
  1171. should always save battery power, but more complicated APM features
  1172. will be dependent on your BIOS implementation. You may need to turn
  1173. this option off if your computer hangs at boot time when using APM
  1174. support, or if it beeps continuously instead of suspending. Turn
  1175. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1176. T400CDT. This is off by default since most machines do fine without
  1177. this feature.
  1178. config APM_CPU_IDLE
  1179. bool "Make CPU Idle calls when idle"
  1180. help
  1181. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1182. On some machines, this can activate improved power savings, such as
  1183. a slowed CPU clock rate, when the machine is idle. These idle calls
  1184. are made after the idle loop has run for some length of time (e.g.,
  1185. 333 mS). On some machines, this will cause a hang at boot time or
  1186. whenever the CPU becomes idle. (On machines with more than one CPU,
  1187. this option does nothing.)
  1188. config APM_DISPLAY_BLANK
  1189. bool "Enable console blanking using APM"
  1190. help
  1191. Enable console blanking using the APM. Some laptops can use this to
  1192. turn off the LCD backlight when the screen blanker of the Linux
  1193. virtual console blanks the screen. Note that this is only used by
  1194. the virtual console screen blanker, and won't turn off the backlight
  1195. when using the X Window system. This also doesn't have anything to
  1196. do with your VESA-compliant power-saving monitor. Further, this
  1197. option doesn't work for all laptops -- it might not turn off your
  1198. backlight at all, or it might print a lot of errors to the console,
  1199. especially if you are using gpm.
  1200. config APM_ALLOW_INTS
  1201. bool "Allow interrupts during APM BIOS calls"
  1202. help
  1203. Normally we disable external interrupts while we are making calls to
  1204. the APM BIOS as a measure to lessen the effects of a badly behaving
  1205. BIOS implementation. The BIOS should reenable interrupts if it
  1206. needs to. Unfortunately, some BIOSes do not -- especially those in
  1207. many of the newer IBM Thinkpads. If you experience hangs when you
  1208. suspend, try setting this to Y. Otherwise, say N.
  1209. config APM_REAL_MODE_POWER_OFF
  1210. bool "Use real mode APM BIOS call to power off"
  1211. help
  1212. Use real mode APM BIOS calls to switch off the computer. This is
  1213. a work-around for a number of buggy BIOSes. Switch this option on if
  1214. your computer crashes instead of powering off properly.
  1215. endif # APM
  1216. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1217. source "drivers/cpuidle/Kconfig"
  1218. endmenu
  1219. menu "Bus options (PCI etc.)"
  1220. config PCI
  1221. bool "PCI support" if !X86_VISWS && !X86_VSMP
  1222. depends on !X86_VOYAGER
  1223. default y
  1224. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1225. help
  1226. Find out whether you have a PCI motherboard. PCI is the name of a
  1227. bus system, i.e. the way the CPU talks to the other stuff inside
  1228. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1229. VESA. If you have PCI, say Y, otherwise N.
  1230. choice
  1231. prompt "PCI access mode"
  1232. depends on X86_32 && PCI && !X86_VISWS
  1233. default PCI_GOANY
  1234. ---help---
  1235. On PCI systems, the BIOS can be used to detect the PCI devices and
  1236. determine their configuration. However, some old PCI motherboards
  1237. have BIOS bugs and may crash if this is done. Also, some embedded
  1238. PCI-based systems don't have any BIOS at all. Linux can also try to
  1239. detect the PCI hardware directly without using the BIOS.
  1240. With this option, you can specify how Linux should detect the
  1241. PCI devices. If you choose "BIOS", the BIOS will be used,
  1242. if you choose "Direct", the BIOS won't be used, and if you
  1243. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1244. If you choose "Any", the kernel will try MMCONFIG, then the
  1245. direct access method and falls back to the BIOS if that doesn't
  1246. work. If unsure, go with the default, which is "Any".
  1247. config PCI_GOBIOS
  1248. bool "BIOS"
  1249. config PCI_GOMMCONFIG
  1250. bool "MMConfig"
  1251. config PCI_GODIRECT
  1252. bool "Direct"
  1253. config PCI_GOANY
  1254. bool "Any"
  1255. config PCI_GOOLPC
  1256. bool "OLPC"
  1257. depends on OLPC
  1258. endchoice
  1259. config PCI_BIOS
  1260. def_bool y
  1261. depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
  1262. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1263. config PCI_DIRECT
  1264. def_bool y
  1265. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
  1266. config PCI_MMCONFIG
  1267. def_bool y
  1268. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1269. config PCI_OLPC
  1270. bool
  1271. depends on PCI && PCI_GOOLPC
  1272. default y
  1273. config PCI_DOMAINS
  1274. def_bool y
  1275. depends on PCI
  1276. config PCI_MMCONFIG
  1277. bool "Support mmconfig PCI config space access"
  1278. depends on X86_64 && PCI && ACPI
  1279. config DMAR
  1280. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1281. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1282. help
  1283. DMA remapping (DMAR) devices support enables independent address
  1284. translations for Direct Memory Access (DMA) from devices.
  1285. These DMA remapping devices are reported via ACPI tables
  1286. and include PCI device scope covered by these DMA
  1287. remapping devices.
  1288. config DMAR_GFX_WA
  1289. def_bool y
  1290. prompt "Support for Graphics workaround"
  1291. depends on DMAR
  1292. help
  1293. Current Graphics drivers tend to use physical address
  1294. for DMA and avoid using DMA APIs. Setting this config
  1295. option permits the IOMMU driver to set a unity map for
  1296. all the OS-visible memory. Hence the driver can continue
  1297. to use physical addresses for DMA.
  1298. config DMAR_FLOPPY_WA
  1299. def_bool y
  1300. depends on DMAR
  1301. help
  1302. Floppy disk drivers are know to bypass DMA API calls
  1303. thereby failing to work when IOMMU is enabled. This
  1304. workaround will setup a 1:1 mapping for the first
  1305. 16M to make floppy (an ISA device) work.
  1306. source "drivers/pci/pcie/Kconfig"
  1307. source "drivers/pci/Kconfig"
  1308. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1309. config ISA_DMA_API
  1310. def_bool y
  1311. if X86_32
  1312. config ISA
  1313. bool "ISA support"
  1314. depends on !(X86_VOYAGER || X86_VISWS)
  1315. help
  1316. Find out whether you have ISA slots on your motherboard. ISA is the
  1317. name of a bus system, i.e. the way the CPU talks to the other stuff
  1318. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1319. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1320. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1321. config EISA
  1322. bool "EISA support"
  1323. depends on ISA
  1324. ---help---
  1325. The Extended Industry Standard Architecture (EISA) bus was
  1326. developed as an open alternative to the IBM MicroChannel bus.
  1327. The EISA bus provided some of the features of the IBM MicroChannel
  1328. bus while maintaining backward compatibility with cards made for
  1329. the older ISA bus. The EISA bus saw limited use between 1988 and
  1330. 1995 when it was made obsolete by the PCI bus.
  1331. Say Y here if you are building a kernel for an EISA-based machine.
  1332. Otherwise, say N.
  1333. source "drivers/eisa/Kconfig"
  1334. config MCA
  1335. bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
  1336. default y if X86_VOYAGER
  1337. help
  1338. MicroChannel Architecture is found in some IBM PS/2 machines and
  1339. laptops. It is a bus system similar to PCI or ISA. See
  1340. <file:Documentation/mca.txt> (and especially the web page given
  1341. there) before attempting to build an MCA bus kernel.
  1342. source "drivers/mca/Kconfig"
  1343. config SCx200
  1344. tristate "NatSemi SCx200 support"
  1345. depends on !X86_VOYAGER
  1346. help
  1347. This provides basic support for National Semiconductor's
  1348. (now AMD's) Geode processors. The driver probes for the
  1349. PCI-IDs of several on-chip devices, so its a good dependency
  1350. for other scx200_* drivers.
  1351. If compiled as a module, the driver is named scx200.
  1352. config SCx200HR_TIMER
  1353. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1354. depends on SCx200 && GENERIC_TIME
  1355. default y
  1356. help
  1357. This driver provides a clocksource built upon the on-chip
  1358. 27MHz high-resolution timer. Its also a workaround for
  1359. NSC Geode SC-1100's buggy TSC, which loses time when the
  1360. processor goes idle (as is done by the scheduler). The
  1361. other workaround is idle=poll boot option.
  1362. config GEODE_MFGPT_TIMER
  1363. def_bool y
  1364. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1365. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1366. help
  1367. This driver provides a clock event source based on the MFGPT
  1368. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1369. MFGPTs have a better resolution and max interval than the
  1370. generic PIT, and are suitable for use as high-res timers.
  1371. config OLPC
  1372. bool "One Laptop Per Child support"
  1373. default n
  1374. help
  1375. Add support for detecting the unique features of the OLPC
  1376. XO hardware.
  1377. endif # X86_32
  1378. config K8_NB
  1379. def_bool y
  1380. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1381. source "drivers/pcmcia/Kconfig"
  1382. source "drivers/pci/hotplug/Kconfig"
  1383. endmenu
  1384. menu "Executable file formats / Emulations"
  1385. source "fs/Kconfig.binfmt"
  1386. config IA32_EMULATION
  1387. bool "IA32 Emulation"
  1388. depends on X86_64
  1389. select COMPAT_BINFMT_ELF
  1390. help
  1391. Include code to run 32-bit programs under a 64-bit kernel. You should
  1392. likely turn this on, unless you're 100% sure that you don't have any
  1393. 32-bit programs left.
  1394. config IA32_AOUT
  1395. tristate "IA32 a.out support"
  1396. depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
  1397. help
  1398. Support old a.out binaries in the 32bit emulation.
  1399. config COMPAT
  1400. def_bool y
  1401. depends on IA32_EMULATION
  1402. config COMPAT_FOR_U64_ALIGNMENT
  1403. def_bool COMPAT
  1404. depends on X86_64
  1405. config SYSVIPC_COMPAT
  1406. def_bool y
  1407. depends on X86_64 && COMPAT && SYSVIPC
  1408. endmenu
  1409. source "net/Kconfig"
  1410. source "drivers/Kconfig"
  1411. source "drivers/firmware/Kconfig"
  1412. source "fs/Kconfig"
  1413. source "arch/x86/Kconfig.debug"
  1414. source "security/Kconfig"
  1415. source "crypto/Kconfig"
  1416. source "arch/x86/kvm/Kconfig"
  1417. source "lib/Kconfig"