Kconfig 57 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 ARCH_DEFCONFIG
  27. string
  28. default "arch/x86/configs/i386_defconfig" if X86_32
  29. default "arch/x86/configs/x86_64_defconfig" if X86_64
  30. config GENERIC_LOCKBREAK
  31. def_bool n
  32. config GENERIC_TIME
  33. def_bool y
  34. config GENERIC_CMOS_UPDATE
  35. def_bool y
  36. config CLOCKSOURCE_WATCHDOG
  37. def_bool y
  38. config GENERIC_CLOCKEVENTS
  39. def_bool y
  40. config GENERIC_CLOCKEVENTS_BROADCAST
  41. def_bool y
  42. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  43. config LOCKDEP_SUPPORT
  44. def_bool y
  45. config STACKTRACE_SUPPORT
  46. def_bool y
  47. config HAVE_LATENCYTOP_SUPPORT
  48. def_bool y
  49. config FAST_CMPXCHG_LOCAL
  50. bool
  51. default y
  52. config MMU
  53. def_bool y
  54. config ZONE_DMA
  55. def_bool y
  56. config SBUS
  57. bool
  58. config GENERIC_ISA_DMA
  59. def_bool y
  60. config GENERIC_IOMAP
  61. def_bool y
  62. config GENERIC_BUG
  63. def_bool y
  64. depends on BUG
  65. config GENERIC_HWEIGHT
  66. def_bool y
  67. config GENERIC_GPIO
  68. def_bool n
  69. config ARCH_MAY_HAVE_PC_FDC
  70. def_bool y
  71. config RWSEM_GENERIC_SPINLOCK
  72. def_bool !X86_XADD
  73. config RWSEM_XCHGADD_ALGORITHM
  74. def_bool X86_XADD
  75. config ARCH_HAS_ILOG2_U32
  76. def_bool n
  77. config ARCH_HAS_ILOG2_U64
  78. def_bool n
  79. config ARCH_HAS_CPU_IDLE_WAIT
  80. def_bool y
  81. config GENERIC_CALIBRATE_DELAY
  82. def_bool y
  83. config GENERIC_TIME_VSYSCALL
  84. bool
  85. default X86_64
  86. config ARCH_HAS_CPU_RELAX
  87. def_bool y
  88. config ARCH_HAS_CACHE_LINE_SIZE
  89. def_bool y
  90. config HAVE_SETUP_PER_CPU_AREA
  91. def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
  92. config HAVE_CPUMASK_OF_CPU_MAP
  93. def_bool X86_64_SMP
  94. config ARCH_HIBERNATION_POSSIBLE
  95. def_bool y
  96. depends on !SMP || !X86_VOYAGER
  97. config ARCH_SUSPEND_POSSIBLE
  98. def_bool y
  99. depends on !X86_VOYAGER
  100. config ZONE_DMA32
  101. bool
  102. default X86_64
  103. config ARCH_POPULATES_NODE_MAP
  104. def_bool y
  105. config AUDIT_ARCH
  106. bool
  107. default X86_64
  108. config ARCH_SUPPORTS_AOUT
  109. def_bool y
  110. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  111. def_bool y
  112. # Use the generic interrupt handling code in kernel/irq/:
  113. config GENERIC_HARDIRQS
  114. bool
  115. default y
  116. config GENERIC_IRQ_PROBE
  117. bool
  118. default y
  119. config GENERIC_PENDING_IRQ
  120. bool
  121. depends on GENERIC_HARDIRQS && SMP
  122. default y
  123. config X86_SMP
  124. bool
  125. depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
  126. select USE_GENERIC_SMP_HELPERS
  127. default y
  128. config X86_32_SMP
  129. def_bool y
  130. depends on X86_32 && SMP
  131. config X86_64_SMP
  132. def_bool y
  133. depends on X86_64 && SMP
  134. config X86_HT
  135. bool
  136. depends on SMP
  137. depends on (X86_32 && !X86_VOYAGER) || X86_64
  138. default y
  139. config X86_BIOS_REBOOT
  140. bool
  141. depends on !X86_VOYAGER
  142. default y
  143. config X86_TRAMPOLINE
  144. bool
  145. depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
  146. default y
  147. config KTIME_SCALAR
  148. def_bool X86_32
  149. source "init/Kconfig"
  150. menu "Processor type and features"
  151. source "kernel/time/Kconfig"
  152. config SMP
  153. bool "Symmetric multi-processing support"
  154. ---help---
  155. This enables support for systems with more than one CPU. If you have
  156. a system with only one CPU, like most personal computers, say N. If
  157. you have a system with more than one CPU, say Y.
  158. If you say N here, the kernel will run on single and multiprocessor
  159. machines, but will use only one CPU of a multiprocessor machine. If
  160. you say Y here, the kernel will run on many, but not all,
  161. singleprocessor machines. On a singleprocessor machine, the kernel
  162. will run faster if you say N here.
  163. Note that if you say Y here and choose architecture "586" or
  164. "Pentium" under "Processor family", the kernel will not work on 486
  165. architectures. Similarly, multiprocessor kernels for the "PPro"
  166. architecture may not work on all Pentium based boards.
  167. People using multiprocessor machines who say Y here should also say
  168. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  169. Management" code will be disabled if you say Y here.
  170. See also <file:Documentation/i386/IO-APIC.txt>,
  171. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  172. <http://www.tldp.org/docs.html#howto>.
  173. If you don't know what to do here, say N.
  174. config X86_FIND_SMP_CONFIG
  175. def_bool y
  176. depends on X86_MPPARSE || X86_VOYAGER
  177. if ACPI
  178. config X86_MPPARSE
  179. def_bool y
  180. bool "Enable MPS table"
  181. depends on X86_LOCAL_APIC
  182. help
  183. For old smp systems that do not have proper acpi support. Newer systems
  184. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  185. endif
  186. if !ACPI
  187. config X86_MPPARSE
  188. def_bool y
  189. depends on X86_LOCAL_APIC
  190. endif
  191. choice
  192. prompt "Subarchitecture Type"
  193. default X86_PC
  194. config X86_PC
  195. bool "PC-compatible"
  196. help
  197. Choose this option if your computer is a standard PC or compatible.
  198. config X86_ELAN
  199. bool "AMD Elan"
  200. depends on X86_32
  201. help
  202. Select this for an AMD Elan processor.
  203. Do not use this option for K6/Athlon/Opteron processors!
  204. If unsure, choose "PC-compatible" instead.
  205. config X86_VOYAGER
  206. bool "Voyager (NCR)"
  207. depends on X86_32 && (SMP || BROKEN) && !PCI
  208. help
  209. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  210. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  211. *** WARNING ***
  212. If you do not specifically know you have a Voyager based machine,
  213. say N here, otherwise the kernel you build will not be bootable.
  214. config X86_GENERICARCH
  215. bool "Generic architecture"
  216. depends on X86_32
  217. help
  218. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  219. subarchitectures. It is intended for a generic binary kernel.
  220. if you select them all, kernel will probe it one by one. and will
  221. fallback to default.
  222. if X86_GENERICARCH
  223. config X86_NUMAQ
  224. bool "NUMAQ (IBM/Sequent)"
  225. depends on SMP && X86_32 && PCI && X86_MPPARSE
  226. select NUMA
  227. help
  228. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  229. NUMA multiquad box. This changes the way that processors are
  230. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  231. of Flat Logical. You will need a new lynxer.elf file to flash your
  232. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  233. config X86_SUMMIT
  234. bool "Summit/EXA (IBM x440)"
  235. depends on X86_32 && SMP
  236. help
  237. This option is needed for IBM systems that use the Summit/EXA chipset.
  238. In particular, it is needed for the x440.
  239. config X86_ES7000
  240. bool "Support for Unisys ES7000 IA32 series"
  241. depends on X86_32 && SMP
  242. help
  243. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  244. supposed to run on an IA32-based Unisys ES7000 system.
  245. config X86_BIGSMP
  246. bool "Support for big SMP systems with more than 8 CPUs"
  247. depends on X86_32 && SMP
  248. help
  249. This option is needed for the systems that have more than 8 CPUs
  250. and if the system is not of any sub-arch type above.
  251. endif
  252. config X86_RDC321X
  253. bool "RDC R-321x SoC"
  254. depends on X86_32
  255. select M486
  256. select X86_REBOOTFIXUPS
  257. select GENERIC_GPIO
  258. select LEDS_CLASS
  259. select LEDS_GPIO
  260. select NEW_LEDS
  261. help
  262. This option is needed for RDC R-321x system-on-chip, also known
  263. as R-8610-(G).
  264. If you don't have one of these chips, you should say N here.
  265. config X86_VSMP
  266. bool "Support for ScaleMP vSMP"
  267. select PARAVIRT
  268. depends on X86_64 && PCI
  269. help
  270. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  271. supposed to run on these EM64T-based machines. Only choose this option
  272. if you have one of these machines.
  273. endchoice
  274. config X86_VISWS
  275. bool "SGI 320/540 (Visual Workstation)"
  276. depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
  277. help
  278. The SGI Visual Workstation series is an IA32-based workstation
  279. based on SGI systems chips with some legacy PC hardware attached.
  280. Say Y here to create a kernel to run on the SGI 320 or 540.
  281. A kernel compiled for the Visual Workstation will run on general
  282. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  283. config SCHED_NO_NO_OMIT_FRAME_POINTER
  284. def_bool y
  285. prompt "Single-depth WCHAN output"
  286. depends on X86_32
  287. help
  288. Calculate simpler /proc/<PID>/wchan values. If this option
  289. is disabled then wchan values will recurse back to the
  290. caller function. This provides more accurate wchan values,
  291. at the expense of slightly more scheduling overhead.
  292. If in doubt, say "Y".
  293. menuconfig PARAVIRT_GUEST
  294. bool "Paravirtualized guest support"
  295. help
  296. Say Y here to get to see options related to running Linux under
  297. various hypervisors. This option alone does not add any kernel code.
  298. If you say N, all options in this submenu will be skipped and disabled.
  299. if PARAVIRT_GUEST
  300. source "arch/x86/xen/Kconfig"
  301. config VMI
  302. bool "VMI Guest support"
  303. select PARAVIRT
  304. depends on X86_32
  305. depends on !X86_VOYAGER
  306. help
  307. VMI provides a paravirtualized interface to the VMware ESX server
  308. (it could be used by other hypervisors in theory too, but is not
  309. at the moment), by linking the kernel to a GPL-ed ROM module
  310. provided by the hypervisor.
  311. config KVM_CLOCK
  312. bool "KVM paravirtualized clock"
  313. select PARAVIRT
  314. select PARAVIRT_CLOCK
  315. depends on !X86_VOYAGER
  316. help
  317. Turning on this option will allow you to run a paravirtualized clock
  318. when running over the KVM hypervisor. Instead of relying on a PIT
  319. (or probably other) emulation by the underlying device model, the host
  320. provides the guest with timing infrastructure such as time of day, and
  321. system time
  322. config KVM_GUEST
  323. bool "KVM Guest support"
  324. select PARAVIRT
  325. depends on !X86_VOYAGER
  326. help
  327. This option enables various optimizations for running under the KVM
  328. hypervisor.
  329. source "arch/x86/lguest/Kconfig"
  330. config PARAVIRT
  331. bool "Enable paravirtualization code"
  332. depends on !X86_VOYAGER
  333. help
  334. This changes the kernel so it can modify itself when it is run
  335. under a hypervisor, potentially improving performance significantly
  336. over full virtualization. However, when run without a hypervisor
  337. the kernel is theoretically slower and slightly larger.
  338. config PARAVIRT_CLOCK
  339. bool
  340. default n
  341. endif
  342. config PARAVIRT_DEBUG
  343. bool "paravirt-ops debugging"
  344. depends on PARAVIRT && DEBUG_KERNEL
  345. help
  346. Enable to debug paravirt_ops internals. Specifically, BUG if
  347. a paravirt_op is missing when it is called.
  348. config MEMTEST
  349. bool "Memtest"
  350. depends on X86_64
  351. help
  352. This option adds a kernel parameter 'memtest', which allows memtest
  353. to be set.
  354. memtest=0, mean disabled; -- default
  355. memtest=1, mean do 1 test pattern;
  356. ...
  357. memtest=4, mean do 4 test patterns.
  358. If you are unsure how to answer this question, answer N.
  359. config X86_SUMMIT_NUMA
  360. def_bool y
  361. depends on X86_32 && NUMA && X86_GENERICARCH
  362. config X86_CYCLONE_TIMER
  363. def_bool y
  364. depends on X86_GENERICARCH
  365. config ES7000_CLUSTERED_APIC
  366. def_bool y
  367. depends on SMP && X86_ES7000 && MPENTIUMIII
  368. source "arch/x86/Kconfig.cpu"
  369. config HPET_TIMER
  370. def_bool X86_64
  371. prompt "HPET Timer Support" if X86_32
  372. help
  373. Use the IA-PC HPET (High Precision Event Timer) to manage
  374. time in preference to the PIT and RTC, if a HPET is
  375. present.
  376. HPET is the next generation timer replacing legacy 8254s.
  377. The HPET provides a stable time base on SMP
  378. systems, unlike the TSC, but it is more expensive to access,
  379. as it is off-chip. You can find the HPET spec at
  380. <http://www.intel.com/hardwaredesign/hpetspec.htm>.
  381. You can safely choose Y here. However, HPET will only be
  382. activated if the platform and the BIOS support this feature.
  383. Otherwise the 8254 will be used for timing services.
  384. Choose N to continue using the legacy 8254 timer.
  385. config HPET_EMULATE_RTC
  386. def_bool y
  387. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  388. # Mark as embedded because too many people got it wrong.
  389. # The code disables itself when not needed.
  390. config DMI
  391. default y
  392. bool "Enable DMI scanning" if EMBEDDED
  393. help
  394. Enabled scanning of DMI to identify machine quirks. Say Y
  395. here unless you have verified that your setup is not
  396. affected by entries in the DMI blacklist. Required by PNP
  397. BIOS code.
  398. config GART_IOMMU
  399. bool "GART IOMMU support" if EMBEDDED
  400. default y
  401. select SWIOTLB
  402. select AGP
  403. depends on X86_64 && PCI
  404. help
  405. Support for full DMA access of devices with 32bit memory access only
  406. on systems with more than 3GB. This is usually needed for USB,
  407. sound, many IDE/SATA chipsets and some other devices.
  408. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  409. based hardware IOMMU and a software bounce buffer based IOMMU used
  410. on Intel systems and as fallback.
  411. The code is only active when needed (enough memory and limited
  412. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  413. too.
  414. config CALGARY_IOMMU
  415. bool "IBM Calgary IOMMU support"
  416. select SWIOTLB
  417. depends on X86_64 && PCI && EXPERIMENTAL
  418. help
  419. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  420. systems. Needed to run systems with more than 3GB of memory
  421. properly with 32-bit PCI devices that do not support DAC
  422. (Double Address Cycle). Calgary also supports bus level
  423. isolation, where all DMAs pass through the IOMMU. This
  424. prevents them from going anywhere except their intended
  425. destination. This catches hard-to-find kernel bugs and
  426. mis-behaving drivers and devices that do not use the DMA-API
  427. properly to set up their DMA buffers. The IOMMU can be
  428. turned off at boot time with the iommu=off parameter.
  429. Normally the kernel will make the right choice by itself.
  430. If unsure, say Y.
  431. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  432. def_bool y
  433. prompt "Should Calgary be enabled by default?"
  434. depends on CALGARY_IOMMU
  435. help
  436. Should Calgary be enabled by default? if you choose 'y', Calgary
  437. will be used (if it exists). If you choose 'n', Calgary will not be
  438. used even if it exists. If you choose 'n' and would like to use
  439. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  440. If unsure, say Y.
  441. config AMD_IOMMU
  442. bool "AMD IOMMU support"
  443. select SWIOTLB
  444. depends on X86_64 && PCI && ACPI
  445. help
  446. With this option you can enable support for AMD IOMMU hardware in
  447. your system. An IOMMU is a hardware component which provides
  448. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  449. can isolate the the DMA memory of different devices and protect the
  450. system from misbehaving device drivers or hardware.
  451. You can find out if your system has an AMD IOMMU if you look into
  452. your BIOS for an option to enable it or if you have an IVRS ACPI
  453. table.
  454. # need this always selected by IOMMU for the VIA workaround
  455. config SWIOTLB
  456. bool
  457. help
  458. Support for software bounce buffers used on x86-64 systems
  459. which don't have a hardware IOMMU (e.g. the current generation
  460. of Intel's x86-64 CPUs). Using this PCI devices which can only
  461. access 32-bits of memory can be used on systems with more than
  462. 3 GB of memory. If unsure, say Y.
  463. config IOMMU_HELPER
  464. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  465. config MAXSMP
  466. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  467. depends on X86_64 && SMP
  468. default n
  469. help
  470. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  471. If unsure, say N.
  472. if MAXSMP
  473. config NR_CPUS
  474. int
  475. default "4096"
  476. endif
  477. if !MAXSMP
  478. config NR_CPUS
  479. int "Maximum number of CPUs (2-4096)"
  480. range 2 4096
  481. depends on SMP
  482. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  483. default "8"
  484. help
  485. This allows you to specify the maximum number of CPUs which this
  486. kernel will support. The maximum supported value is 4096 and the
  487. minimum value which makes sense is 2.
  488. This is purely to save memory - each supported CPU adds
  489. approximately eight kilobytes to the kernel image.
  490. endif
  491. config SCHED_SMT
  492. bool "SMT (Hyperthreading) scheduler support"
  493. depends on X86_HT
  494. help
  495. SMT scheduler support improves the CPU scheduler's decision making
  496. when dealing with Intel Pentium 4 chips with HyperThreading at a
  497. cost of slightly increased overhead in some places. If unsure say
  498. N here.
  499. config SCHED_MC
  500. def_bool y
  501. prompt "Multi-core scheduler support"
  502. depends on X86_HT
  503. help
  504. Multi-core scheduler support improves the CPU scheduler's decision
  505. making when dealing with multi-core CPU chips at a cost of slightly
  506. increased overhead in some places. If unsure say N here.
  507. source "kernel/Kconfig.preempt"
  508. config X86_UP_APIC
  509. bool "Local APIC support on uniprocessors"
  510. depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
  511. help
  512. A local APIC (Advanced Programmable Interrupt Controller) is an
  513. integrated interrupt controller in the CPU. If you have a single-CPU
  514. system which has a processor with a local APIC, you can say Y here to
  515. enable and use it. If you say Y here even though your machine doesn't
  516. have a local APIC, then the kernel will still run with no slowdown at
  517. all. The local APIC supports CPU-generated self-interrupts (timer,
  518. performance counters), and the NMI watchdog which detects hard
  519. lockups.
  520. config X86_UP_IOAPIC
  521. bool "IO-APIC support on uniprocessors"
  522. depends on X86_UP_APIC
  523. help
  524. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  525. SMP-capable replacement for PC-style interrupt controllers. Most
  526. SMP systems and many recent uniprocessor systems have one.
  527. If you have a single-CPU system with an IO-APIC, you can say Y here
  528. to use it. If you say Y here even though your machine doesn't have
  529. an IO-APIC, then the kernel will still run with no slowdown at all.
  530. config X86_LOCAL_APIC
  531. def_bool y
  532. depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
  533. config X86_IO_APIC
  534. def_bool y
  535. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
  536. config X86_VISWS_APIC
  537. def_bool y
  538. depends on X86_32 && X86_VISWS
  539. config X86_MCE
  540. bool "Machine Check Exception"
  541. depends on !X86_VOYAGER
  542. ---help---
  543. Machine Check Exception support allows the processor to notify the
  544. kernel if it detects a problem (e.g. overheating, component failure).
  545. The action the kernel takes depends on the severity of the problem,
  546. ranging from a warning message on the console, to halting the machine.
  547. Your processor must be a Pentium or newer to support this - check the
  548. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  549. have a design flaw which leads to false MCE events - hence MCE is
  550. disabled on all P5 processors, unless explicitly enabled with "mce"
  551. as a boot argument. Similarly, if MCE is built in and creates a
  552. problem on some new non-standard machine, you can boot with "nomce"
  553. to disable it. MCE support simply ignores non-MCE processors like
  554. the 386 and 486, so nearly everyone can say Y here.
  555. config X86_MCE_INTEL
  556. def_bool y
  557. prompt "Intel MCE features"
  558. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  559. help
  560. Additional support for intel specific MCE features such as
  561. the thermal monitor.
  562. config X86_MCE_AMD
  563. def_bool y
  564. prompt "AMD MCE features"
  565. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  566. help
  567. Additional support for AMD specific MCE features such as
  568. the DRAM Error Threshold.
  569. config X86_MCE_NONFATAL
  570. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  571. depends on X86_32 && X86_MCE
  572. help
  573. Enabling this feature starts a timer that triggers every 5 seconds which
  574. will look at the machine check registers to see if anything happened.
  575. Non-fatal problems automatically get corrected (but still logged).
  576. Disable this if you don't want to see these messages.
  577. Seeing the messages this option prints out may be indicative of dying
  578. or out-of-spec (ie, overclocked) hardware.
  579. This option only does something on certain CPUs.
  580. (AMD Athlon/Duron and Intel Pentium 4)
  581. config X86_MCE_P4THERMAL
  582. bool "check for P4 thermal throttling interrupt."
  583. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
  584. help
  585. Enabling this feature will cause a message to be printed when the P4
  586. enters thermal throttling.
  587. config VM86
  588. bool "Enable VM86 support" if EMBEDDED
  589. default y
  590. depends on X86_32
  591. help
  592. This option is required by programs like DOSEMU to run 16-bit legacy
  593. code on X86 processors. It also may be needed by software like
  594. XFree86 to initialize some video cards via BIOS. Disabling this
  595. option saves about 6k.
  596. config TOSHIBA
  597. tristate "Toshiba Laptop support"
  598. depends on X86_32
  599. ---help---
  600. This adds a driver to safely access the System Management Mode of
  601. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  602. not work on models with a Phoenix BIOS. The System Management Mode
  603. is used to set the BIOS and power saving options on Toshiba portables.
  604. For information on utilities to make use of this driver see the
  605. Toshiba Linux utilities web site at:
  606. <http://www.buzzard.org.uk/toshiba/>.
  607. Say Y if you intend to run this kernel on a Toshiba portable.
  608. Say N otherwise.
  609. config I8K
  610. tristate "Dell laptop support"
  611. ---help---
  612. This adds a driver to safely access the System Management Mode
  613. of the CPU on the Dell Inspiron 8000. The System Management Mode
  614. is used to read cpu temperature and cooling fan status and to
  615. control the fans on the I8K portables.
  616. This driver has been tested only on the Inspiron 8000 but it may
  617. also work with other Dell laptops. You can force loading on other
  618. models by passing the parameter `force=1' to the module. Use at
  619. your own risk.
  620. For information on utilities to make use of this driver see the
  621. I8K Linux utilities web site at:
  622. <http://people.debian.org/~dz/i8k/>
  623. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  624. Say N otherwise.
  625. config X86_REBOOTFIXUPS
  626. def_bool n
  627. prompt "Enable X86 board specific fixups for reboot"
  628. depends on X86_32 && X86
  629. ---help---
  630. This enables chipset and/or board specific fixups to be done
  631. in order to get reboot to work correctly. This is only needed on
  632. some combinations of hardware and BIOS. The symptom, for which
  633. this config is intended, is when reboot ends with a stalled/hung
  634. system.
  635. Currently, the only fixup is for the Geode machines using
  636. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  637. Say Y if you want to enable the fixup. Currently, it's safe to
  638. enable this option even if you don't need it.
  639. Say N otherwise.
  640. config MICROCODE
  641. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  642. select FW_LOADER
  643. ---help---
  644. If you say Y here, you will be able to update the microcode on
  645. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  646. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  647. actual microcode binary data itself which is not shipped with the
  648. Linux kernel.
  649. For latest news and information on obtaining all the required
  650. ingredients for this driver, check:
  651. <http://www.urbanmyth.org/microcode/>.
  652. To compile this driver as a module, choose M here: the
  653. module will be called microcode.
  654. config MICROCODE_OLD_INTERFACE
  655. def_bool y
  656. depends on MICROCODE
  657. config X86_MSR
  658. tristate "/dev/cpu/*/msr - Model-specific register support"
  659. help
  660. This device gives privileged processes access to the x86
  661. Model-Specific Registers (MSRs). It is a character device with
  662. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  663. MSR accesses are directed to a specific CPU on multi-processor
  664. systems.
  665. config X86_CPUID
  666. tristate "/dev/cpu/*/cpuid - CPU information support"
  667. help
  668. This device gives processes access to the x86 CPUID instruction to
  669. be executed on a specific processor. It is a character device
  670. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  671. /dev/cpu/31/cpuid.
  672. choice
  673. prompt "High Memory Support"
  674. default HIGHMEM4G if !X86_NUMAQ
  675. default HIGHMEM64G if X86_NUMAQ
  676. depends on X86_32
  677. config NOHIGHMEM
  678. bool "off"
  679. depends on !X86_NUMAQ
  680. ---help---
  681. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  682. However, the address space of 32-bit x86 processors is only 4
  683. Gigabytes large. That means that, if you have a large amount of
  684. physical memory, not all of it can be "permanently mapped" by the
  685. kernel. The physical memory that's not permanently mapped is called
  686. "high memory".
  687. If you are compiling a kernel which will never run on a machine with
  688. more than 1 Gigabyte total physical RAM, answer "off" here (default
  689. choice and suitable for most users). This will result in a "3GB/1GB"
  690. split: 3GB are mapped so that each process sees a 3GB virtual memory
  691. space and the remaining part of the 4GB virtual memory space is used
  692. by the kernel to permanently map as much physical memory as
  693. possible.
  694. If the machine has between 1 and 4 Gigabytes physical RAM, then
  695. answer "4GB" here.
  696. If more than 4 Gigabytes is used then answer "64GB" here. This
  697. selection turns Intel PAE (Physical Address Extension) mode on.
  698. PAE implements 3-level paging on IA32 processors. PAE is fully
  699. supported by Linux, PAE mode is implemented on all recent Intel
  700. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  701. then the kernel will not boot on CPUs that don't support PAE!
  702. The actual amount of total physical memory will either be
  703. auto detected or can be forced by using a kernel command line option
  704. such as "mem=256M". (Try "man bootparam" or see the documentation of
  705. your boot loader (lilo or loadlin) about how to pass options to the
  706. kernel at boot time.)
  707. If unsure, say "off".
  708. config HIGHMEM4G
  709. bool "4GB"
  710. depends on !X86_NUMAQ
  711. help
  712. Select this if you have a 32-bit processor and between 1 and 4
  713. gigabytes of physical RAM.
  714. config HIGHMEM64G
  715. bool "64GB"
  716. depends on !M386 && !M486
  717. select X86_PAE
  718. help
  719. Select this if you have a 32-bit processor and more than 4
  720. gigabytes of physical RAM.
  721. endchoice
  722. choice
  723. depends on EXPERIMENTAL
  724. prompt "Memory split" if EMBEDDED
  725. default VMSPLIT_3G
  726. depends on X86_32
  727. help
  728. Select the desired split between kernel and user memory.
  729. If the address range available to the kernel is less than the
  730. physical memory installed, the remaining memory will be available
  731. as "high memory". Accessing high memory is a little more costly
  732. than low memory, as it needs to be mapped into the kernel first.
  733. Note that increasing the kernel address space limits the range
  734. available to user programs, making the address space there
  735. tighter. Selecting anything other than the default 3G/1G split
  736. will also likely make your kernel incompatible with binary-only
  737. kernel modules.
  738. If you are not absolutely sure what you are doing, leave this
  739. option alone!
  740. config VMSPLIT_3G
  741. bool "3G/1G user/kernel split"
  742. config VMSPLIT_3G_OPT
  743. depends on !X86_PAE
  744. bool "3G/1G user/kernel split (for full 1G low memory)"
  745. config VMSPLIT_2G
  746. bool "2G/2G user/kernel split"
  747. config VMSPLIT_2G_OPT
  748. depends on !X86_PAE
  749. bool "2G/2G user/kernel split (for full 2G low memory)"
  750. config VMSPLIT_1G
  751. bool "1G/3G user/kernel split"
  752. endchoice
  753. config PAGE_OFFSET
  754. hex
  755. default 0xB0000000 if VMSPLIT_3G_OPT
  756. default 0x80000000 if VMSPLIT_2G
  757. default 0x78000000 if VMSPLIT_2G_OPT
  758. default 0x40000000 if VMSPLIT_1G
  759. default 0xC0000000
  760. depends on X86_32
  761. config HIGHMEM
  762. def_bool y
  763. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  764. config X86_PAE
  765. def_bool n
  766. prompt "PAE (Physical Address Extension) Support"
  767. depends on X86_32 && !HIGHMEM4G
  768. select RESOURCES_64BIT
  769. help
  770. PAE is required for NX support, and furthermore enables
  771. larger swapspace support for non-overcommit purposes. It
  772. has the cost of more pagetable lookup overhead, and also
  773. consumes more pagetable space per process.
  774. # Common NUMA Features
  775. config NUMA
  776. bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
  777. depends on SMP
  778. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  779. default n if X86_PC
  780. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  781. help
  782. Enable NUMA (Non Uniform Memory Access) support.
  783. The kernel will try to allocate memory used by a CPU on the
  784. local memory controller of the CPU and add some more
  785. NUMA awareness to the kernel.
  786. For i386 this is currently highly experimental and should be only
  787. used for kernel development. It might also cause boot failures.
  788. For x86_64 this is recommended on all multiprocessor Opteron systems.
  789. If the system is EM64T, you should say N unless your system is
  790. EM64T NUMA.
  791. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  792. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  793. config K8_NUMA
  794. def_bool y
  795. prompt "Old style AMD Opteron NUMA detection"
  796. depends on X86_64 && NUMA && PCI
  797. help
  798. Enable K8 NUMA node topology detection. You should say Y here if
  799. you have a multi processor AMD K8 system. This uses an old
  800. method to read the NUMA configuration directly from the builtin
  801. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  802. instead, which also takes priority if both are compiled in.
  803. config X86_64_ACPI_NUMA
  804. def_bool y
  805. prompt "ACPI NUMA detection"
  806. depends on X86_64 && NUMA && ACPI && PCI
  807. select ACPI_NUMA
  808. help
  809. Enable ACPI SRAT based node topology detection.
  810. # Some NUMA nodes have memory ranges that span
  811. # other nodes. Even though a pfn is valid and
  812. # between a node's start and end pfns, it may not
  813. # reside on that node. See memmap_init_zone()
  814. # for details.
  815. config NODES_SPAN_OTHER_NODES
  816. def_bool y
  817. depends on X86_64_ACPI_NUMA
  818. config NUMA_EMU
  819. bool "NUMA emulation"
  820. depends on X86_64 && NUMA
  821. help
  822. Enable NUMA emulation. A flat machine will be split
  823. into virtual nodes when booted with "numa=fake=N", where N is the
  824. number of nodes. This is only useful for debugging.
  825. if MAXSMP
  826. config NODES_SHIFT
  827. int
  828. default "9"
  829. endif
  830. if !MAXSMP
  831. config NODES_SHIFT
  832. int "Maximum NUMA Nodes (as a power of 2)"
  833. range 1 9 if X86_64
  834. default "6" if X86_64
  835. default "4" if X86_NUMAQ
  836. default "3"
  837. depends on NEED_MULTIPLE_NODES
  838. help
  839. Specify the maximum number of NUMA Nodes available on the target
  840. system. Increases memory reserved to accomodate various tables.
  841. endif
  842. config HAVE_ARCH_BOOTMEM_NODE
  843. def_bool y
  844. depends on X86_32 && NUMA
  845. config ARCH_HAVE_MEMORY_PRESENT
  846. def_bool y
  847. depends on X86_32 && DISCONTIGMEM
  848. config NEED_NODE_MEMMAP_SIZE
  849. def_bool y
  850. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  851. config HAVE_ARCH_ALLOC_REMAP
  852. def_bool y
  853. depends on X86_32 && NUMA
  854. config ARCH_FLATMEM_ENABLE
  855. def_bool y
  856. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
  857. config ARCH_DISCONTIGMEM_ENABLE
  858. def_bool y
  859. depends on NUMA && X86_32
  860. config ARCH_DISCONTIGMEM_DEFAULT
  861. def_bool y
  862. depends on NUMA && X86_32
  863. config ARCH_SPARSEMEM_DEFAULT
  864. def_bool y
  865. depends on X86_64
  866. config ARCH_SPARSEMEM_ENABLE
  867. def_bool y
  868. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
  869. select SPARSEMEM_STATIC if X86_32
  870. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  871. config ARCH_SELECT_MEMORY_MODEL
  872. def_bool y
  873. depends on ARCH_SPARSEMEM_ENABLE
  874. config ARCH_MEMORY_PROBE
  875. def_bool X86_64
  876. depends on MEMORY_HOTPLUG
  877. source "mm/Kconfig"
  878. config HIGHPTE
  879. bool "Allocate 3rd-level pagetables from highmem"
  880. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  881. help
  882. The VM uses one page table entry for each page of physical memory.
  883. For systems with a lot of RAM, this can be wasteful of precious
  884. low memory. Setting this option will put user-space page table
  885. entries in high memory.
  886. config MATH_EMULATION
  887. bool
  888. prompt "Math emulation" if X86_32
  889. ---help---
  890. Linux can emulate a math coprocessor (used for floating point
  891. operations) if you don't have one. 486DX and Pentium processors have
  892. a math coprocessor built in, 486SX and 386 do not, unless you added
  893. a 487DX or 387, respectively. (The messages during boot time can
  894. give you some hints here ["man dmesg"].) Everyone needs either a
  895. coprocessor or this emulation.
  896. If you don't have a math coprocessor, you need to say Y here; if you
  897. say Y here even though you have a coprocessor, the coprocessor will
  898. be used nevertheless. (This behavior can be changed with the kernel
  899. command line option "no387", which comes handy if your coprocessor
  900. is broken. Try "man bootparam" or see the documentation of your boot
  901. loader (lilo or loadlin) about how to pass options to the kernel at
  902. boot time.) This means that it is a good idea to say Y here if you
  903. intend to use this kernel on different machines.
  904. More information about the internals of the Linux math coprocessor
  905. emulation can be found in <file:arch/x86/math-emu/README>.
  906. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  907. kernel, it won't hurt.
  908. config MTRR
  909. bool "MTRR (Memory Type Range Register) support"
  910. ---help---
  911. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  912. the Memory Type Range Registers (MTRRs) may be used to control
  913. processor access to memory ranges. This is most useful if you have
  914. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  915. allows bus write transfers to be combined into a larger transfer
  916. before bursting over the PCI/AGP bus. This can increase performance
  917. of image write operations 2.5 times or more. Saying Y here creates a
  918. /proc/mtrr file which may be used to manipulate your processor's
  919. MTRRs. Typically the X server should use this.
  920. This code has a reasonably generic interface so that similar
  921. control registers on other processors can be easily supported
  922. as well:
  923. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  924. Registers (ARRs) which provide a similar functionality to MTRRs. For
  925. these, the ARRs are used to emulate the MTRRs.
  926. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  927. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  928. write-combining. All of these processors are supported by this code
  929. and it makes sense to say Y here if you have one of them.
  930. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  931. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  932. can lead to all sorts of problems, so it's good to say Y here.
  933. You can safely say Y even if your machine doesn't have MTRRs, you'll
  934. just add about 9 KB to your kernel.
  935. See <file:Documentation/mtrr.txt> for more information.
  936. config MTRR_SANITIZER
  937. bool
  938. prompt "MTRR cleanup support"
  939. depends on MTRR
  940. help
  941. Convert MTRR layout from continuous to discrete, so X drivers can
  942. add writeback entries.
  943. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  944. The largest mtrr entry size for a continous block can be set with
  945. mtrr_chunk_size.
  946. If unsure, say N.
  947. config MTRR_SANITIZER_ENABLE_DEFAULT
  948. int "MTRR cleanup enable value (0-1)"
  949. range 0 1
  950. default "0"
  951. depends on MTRR_SANITIZER
  952. help
  953. Enable mtrr cleanup default value
  954. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  955. int "MTRR cleanup spare reg num (0-7)"
  956. range 0 7
  957. default "1"
  958. depends on MTRR_SANITIZER
  959. help
  960. mtrr cleanup spare entries default, it can be changed via
  961. mtrr_spare_reg_nr=N on the kernel command line.
  962. config X86_PAT
  963. bool
  964. prompt "x86 PAT support"
  965. depends on MTRR
  966. help
  967. Use PAT attributes to setup page level cache control.
  968. PATs are the modern equivalents of MTRRs and are much more
  969. flexible than MTRRs.
  970. Say N here if you see bootup problems (boot crash, boot hang,
  971. spontaneous reboots) or a non-working video driver.
  972. If unsure, say Y.
  973. config EFI
  974. def_bool n
  975. prompt "EFI runtime service support"
  976. depends on ACPI
  977. ---help---
  978. This enables the kernel to use EFI runtime services that are
  979. available (such as the EFI variable services).
  980. This option is only useful on systems that have EFI firmware.
  981. In addition, you should use the latest ELILO loader available
  982. at <http://elilo.sourceforge.net> in order to take advantage
  983. of EFI runtime services. However, even with this option, the
  984. resultant kernel should continue to boot on existing non-EFI
  985. platforms.
  986. config IRQBALANCE
  987. def_bool y
  988. prompt "Enable kernel irq balancing"
  989. depends on X86_32 && SMP && X86_IO_APIC
  990. help
  991. The default yes will allow the kernel to do irq load balancing.
  992. Saying no will keep the kernel from doing irq load balancing.
  993. config SECCOMP
  994. def_bool y
  995. prompt "Enable seccomp to safely compute untrusted bytecode"
  996. depends on PROC_FS
  997. help
  998. This kernel feature is useful for number crunching applications
  999. that may need to compute untrusted bytecode during their
  1000. execution. By using pipes or other transports made available to
  1001. the process as file descriptors supporting the read/write
  1002. syscalls, it's possible to isolate those applications in
  1003. their own address space using seccomp. Once seccomp is
  1004. enabled via /proc/<pid>/seccomp, it cannot be disabled
  1005. and the task is only allowed to execute a few safe syscalls
  1006. defined by each seccomp mode.
  1007. If unsure, say Y. Only embedded should say N here.
  1008. config CC_STACKPROTECTOR
  1009. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1010. depends on X86_64 && EXPERIMENTAL && BROKEN
  1011. help
  1012. This option turns on the -fstack-protector GCC feature. This
  1013. feature puts, at the beginning of critical functions, a canary
  1014. value on the stack just before the return address, and validates
  1015. the value just before actually returning. Stack based buffer
  1016. overflows (that need to overwrite this return address) now also
  1017. overwrite the canary, which gets detected and the attack is then
  1018. neutralized via a kernel panic.
  1019. This feature requires gcc version 4.2 or above, or a distribution
  1020. gcc with the feature backported. Older versions are automatically
  1021. detected and for those versions, this configuration option is ignored.
  1022. config CC_STACKPROTECTOR_ALL
  1023. bool "Use stack-protector for all functions"
  1024. depends on CC_STACKPROTECTOR
  1025. help
  1026. Normally, GCC only inserts the canary value protection for
  1027. functions that use large-ish on-stack buffers. By enabling
  1028. this option, GCC will be asked to do this for ALL functions.
  1029. source kernel/Kconfig.hz
  1030. config KEXEC
  1031. bool "kexec system call"
  1032. depends on X86_BIOS_REBOOT
  1033. help
  1034. kexec is a system call that implements the ability to shutdown your
  1035. current kernel, and to start another kernel. It is like a reboot
  1036. but it is independent of the system firmware. And like a reboot
  1037. you can start any kernel with it, not just Linux.
  1038. The name comes from the similarity to the exec system call.
  1039. It is an ongoing process to be certain the hardware in a machine
  1040. is properly shutdown, so do not be surprised if this code does not
  1041. initially work for you. It may help to enable device hotplugging
  1042. support. As of this writing the exact hardware interface is
  1043. strongly in flux, so no good recommendation can be made.
  1044. config CRASH_DUMP
  1045. bool "kernel crash dumps (EXPERIMENTAL)"
  1046. depends on X86_64 || (X86_32 && HIGHMEM)
  1047. help
  1048. Generate crash dump after being started by kexec.
  1049. This should be normally only set in special crash dump kernels
  1050. which are loaded in the main kernel with kexec-tools into
  1051. a specially reserved region and then later executed after
  1052. a crash by kdump/kexec. The crash dump kernel must be compiled
  1053. to a memory address not used by the main kernel or BIOS using
  1054. PHYSICAL_START, or it must be built as a relocatable image
  1055. (CONFIG_RELOCATABLE=y).
  1056. For more details see Documentation/kdump/kdump.txt
  1057. config PHYSICAL_START
  1058. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1059. default "0x1000000" if X86_NUMAQ
  1060. default "0x200000" if X86_64
  1061. default "0x100000"
  1062. help
  1063. This gives the physical address where the kernel is loaded.
  1064. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1065. bzImage will decompress itself to above physical address and
  1066. run from there. Otherwise, bzImage will run from the address where
  1067. it has been loaded by the boot loader and will ignore above physical
  1068. address.
  1069. In normal kdump cases one does not have to set/change this option
  1070. as now bzImage can be compiled as a completely relocatable image
  1071. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1072. address. This option is mainly useful for the folks who don't want
  1073. to use a bzImage for capturing the crash dump and want to use a
  1074. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1075. to be specifically compiled to run from a specific memory area
  1076. (normally a reserved region) and this option comes handy.
  1077. So if you are using bzImage for capturing the crash dump, leave
  1078. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  1079. Otherwise if you plan to use vmlinux for capturing the crash dump
  1080. change this value to start of the reserved region (Typically 16MB
  1081. 0x1000000). In other words, it can be set based on the "X" value as
  1082. specified in the "crashkernel=YM@XM" command line boot parameter
  1083. passed to the panic-ed kernel. Typically this parameter is set as
  1084. crashkernel=64M@16M. Please take a look at
  1085. Documentation/kdump/kdump.txt for more details about crash dumps.
  1086. Usage of bzImage for capturing the crash dump is recommended as
  1087. one does not have to build two kernels. Same kernel can be used
  1088. as production kernel and capture kernel. Above option should have
  1089. gone away after relocatable bzImage support is introduced. But it
  1090. is present because there are users out there who continue to use
  1091. vmlinux for dump capture. This option should go away down the
  1092. line.
  1093. Don't change this unless you know what you are doing.
  1094. config RELOCATABLE
  1095. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1096. depends on EXPERIMENTAL
  1097. help
  1098. This builds a kernel image that retains relocation information
  1099. so it can be loaded someplace besides the default 1MB.
  1100. The relocations tend to make the kernel binary about 10% larger,
  1101. but are discarded at runtime.
  1102. One use is for the kexec on panic case where the recovery kernel
  1103. must live at a different physical address than the primary
  1104. kernel.
  1105. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1106. it has been loaded at and the compile time physical address
  1107. (CONFIG_PHYSICAL_START) is ignored.
  1108. config PHYSICAL_ALIGN
  1109. hex
  1110. prompt "Alignment value to which kernel should be aligned" if X86_32
  1111. default "0x100000" if X86_32
  1112. default "0x200000" if X86_64
  1113. range 0x2000 0x400000
  1114. help
  1115. This value puts the alignment restrictions on physical address
  1116. where kernel is loaded and run from. Kernel is compiled for an
  1117. address which meets above alignment restriction.
  1118. If bootloader loads the kernel at a non-aligned address and
  1119. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1120. address aligned to above value and run from there.
  1121. If bootloader loads the kernel at a non-aligned address and
  1122. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1123. load address and decompress itself to the address it has been
  1124. compiled for and run from there. The address for which kernel is
  1125. compiled already meets above alignment restrictions. Hence the
  1126. end result is that kernel runs from a physical address meeting
  1127. above alignment restrictions.
  1128. Don't change this unless you know what you are doing.
  1129. config HOTPLUG_CPU
  1130. bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
  1131. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  1132. ---help---
  1133. Say Y here to experiment with turning CPUs off and on, and to
  1134. enable suspend on SMP systems. CPUs can be controlled through
  1135. /sys/devices/system/cpu.
  1136. Say N if you want to disable CPU hotplug and don't need to
  1137. suspend.
  1138. config COMPAT_VDSO
  1139. def_bool y
  1140. prompt "Compat VDSO support"
  1141. depends on X86_32 || IA32_EMULATION
  1142. help
  1143. Map the 32-bit VDSO to the predictable old-style address too.
  1144. ---help---
  1145. Say N here if you are running a sufficiently recent glibc
  1146. version (2.3.3 or later), to remove the high-mapped
  1147. VDSO mapping and to exclusively use the randomized VDSO.
  1148. If unsure, say Y.
  1149. endmenu
  1150. config ARCH_ENABLE_MEMORY_HOTPLUG
  1151. def_bool y
  1152. depends on X86_64 || (X86_32 && HIGHMEM)
  1153. config HAVE_ARCH_EARLY_PFN_TO_NID
  1154. def_bool X86_64
  1155. depends on NUMA
  1156. menu "Power management options"
  1157. depends on !X86_VOYAGER
  1158. config ARCH_HIBERNATION_HEADER
  1159. def_bool y
  1160. depends on X86_64 && HIBERNATION
  1161. source "kernel/power/Kconfig"
  1162. source "drivers/acpi/Kconfig"
  1163. config X86_APM_BOOT
  1164. bool
  1165. default y
  1166. depends on APM || APM_MODULE
  1167. menuconfig APM
  1168. tristate "APM (Advanced Power Management) BIOS support"
  1169. depends on X86_32 && PM_SLEEP
  1170. ---help---
  1171. APM is a BIOS specification for saving power using several different
  1172. techniques. This is mostly useful for battery powered laptops with
  1173. APM compliant BIOSes. If you say Y here, the system time will be
  1174. reset after a RESUME operation, the /proc/apm device will provide
  1175. battery status information, and user-space programs will receive
  1176. notification of APM "events" (e.g. battery status change).
  1177. If you select "Y" here, you can disable actual use of the APM
  1178. BIOS by passing the "apm=off" option to the kernel at boot time.
  1179. Note that the APM support is almost completely disabled for
  1180. machines with more than one CPU.
  1181. In order to use APM, you will need supporting software. For location
  1182. and more information, read <file:Documentation/power/pm.txt> and the
  1183. Battery Powered Linux mini-HOWTO, available from
  1184. <http://www.tldp.org/docs.html#howto>.
  1185. This driver does not spin down disk drives (see the hdparm(8)
  1186. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1187. VESA-compliant "green" monitors.
  1188. This driver does not support the TI 4000M TravelMate and the ACER
  1189. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1190. desktop machines also don't have compliant BIOSes, and this driver
  1191. may cause those machines to panic during the boot phase.
  1192. Generally, if you don't have a battery in your machine, there isn't
  1193. much point in using this driver and you should say N. If you get
  1194. random kernel OOPSes or reboots that don't seem to be related to
  1195. anything, try disabling/enabling this option (or disabling/enabling
  1196. APM in your BIOS).
  1197. Some other things you should try when experiencing seemingly random,
  1198. "weird" problems:
  1199. 1) make sure that you have enough swap space and that it is
  1200. enabled.
  1201. 2) pass the "no-hlt" option to the kernel
  1202. 3) switch on floating point emulation in the kernel and pass
  1203. the "no387" option to the kernel
  1204. 4) pass the "floppy=nodma" option to the kernel
  1205. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1206. all but the first 4 MB of RAM)
  1207. 6) make sure that the CPU is not over clocked.
  1208. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1209. 8) disable the cache from your BIOS settings
  1210. 9) install a fan for the video card or exchange video RAM
  1211. 10) install a better fan for the CPU
  1212. 11) exchange RAM chips
  1213. 12) exchange the motherboard.
  1214. To compile this driver as a module, choose M here: the
  1215. module will be called apm.
  1216. if APM
  1217. config APM_IGNORE_USER_SUSPEND
  1218. bool "Ignore USER SUSPEND"
  1219. help
  1220. This option will ignore USER SUSPEND requests. On machines with a
  1221. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1222. series notebooks, it is necessary to say Y because of a BIOS bug.
  1223. config APM_DO_ENABLE
  1224. bool "Enable PM at boot time"
  1225. ---help---
  1226. Enable APM features at boot time. From page 36 of the APM BIOS
  1227. specification: "When disabled, the APM BIOS does not automatically
  1228. power manage devices, enter the Standby State, enter the Suspend
  1229. State, or take power saving steps in response to CPU Idle calls."
  1230. This driver will make CPU Idle calls when Linux is idle (unless this
  1231. feature is turned off -- see "Do CPU IDLE calls", below). This
  1232. should always save battery power, but more complicated APM features
  1233. will be dependent on your BIOS implementation. You may need to turn
  1234. this option off if your computer hangs at boot time when using APM
  1235. support, or if it beeps continuously instead of suspending. Turn
  1236. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1237. T400CDT. This is off by default since most machines do fine without
  1238. this feature.
  1239. config APM_CPU_IDLE
  1240. bool "Make CPU Idle calls when idle"
  1241. help
  1242. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1243. On some machines, this can activate improved power savings, such as
  1244. a slowed CPU clock rate, when the machine is idle. These idle calls
  1245. are made after the idle loop has run for some length of time (e.g.,
  1246. 333 mS). On some machines, this will cause a hang at boot time or
  1247. whenever the CPU becomes idle. (On machines with more than one CPU,
  1248. this option does nothing.)
  1249. config APM_DISPLAY_BLANK
  1250. bool "Enable console blanking using APM"
  1251. help
  1252. Enable console blanking using the APM. Some laptops can use this to
  1253. turn off the LCD backlight when the screen blanker of the Linux
  1254. virtual console blanks the screen. Note that this is only used by
  1255. the virtual console screen blanker, and won't turn off the backlight
  1256. when using the X Window system. This also doesn't have anything to
  1257. do with your VESA-compliant power-saving monitor. Further, this
  1258. option doesn't work for all laptops -- it might not turn off your
  1259. backlight at all, or it might print a lot of errors to the console,
  1260. especially if you are using gpm.
  1261. config APM_ALLOW_INTS
  1262. bool "Allow interrupts during APM BIOS calls"
  1263. help
  1264. Normally we disable external interrupts while we are making calls to
  1265. the APM BIOS as a measure to lessen the effects of a badly behaving
  1266. BIOS implementation. The BIOS should reenable interrupts if it
  1267. needs to. Unfortunately, some BIOSes do not -- especially those in
  1268. many of the newer IBM Thinkpads. If you experience hangs when you
  1269. suspend, try setting this to Y. Otherwise, say N.
  1270. config APM_REAL_MODE_POWER_OFF
  1271. bool "Use real mode APM BIOS call to power off"
  1272. help
  1273. Use real mode APM BIOS calls to switch off the computer. This is
  1274. a work-around for a number of buggy BIOSes. Switch this option on if
  1275. your computer crashes instead of powering off properly.
  1276. endif # APM
  1277. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1278. source "drivers/cpuidle/Kconfig"
  1279. endmenu
  1280. menu "Bus options (PCI etc.)"
  1281. config PCI
  1282. bool "PCI support"
  1283. default y
  1284. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1285. help
  1286. Find out whether you have a PCI motherboard. PCI is the name of a
  1287. bus system, i.e. the way the CPU talks to the other stuff inside
  1288. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1289. VESA. If you have PCI, say Y, otherwise N.
  1290. choice
  1291. prompt "PCI access mode"
  1292. depends on X86_32 && PCI
  1293. default PCI_GOANY
  1294. ---help---
  1295. On PCI systems, the BIOS can be used to detect the PCI devices and
  1296. determine their configuration. However, some old PCI motherboards
  1297. have BIOS bugs and may crash if this is done. Also, some embedded
  1298. PCI-based systems don't have any BIOS at all. Linux can also try to
  1299. detect the PCI hardware directly without using the BIOS.
  1300. With this option, you can specify how Linux should detect the
  1301. PCI devices. If you choose "BIOS", the BIOS will be used,
  1302. if you choose "Direct", the BIOS won't be used, and if you
  1303. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1304. If you choose "Any", the kernel will try MMCONFIG, then the
  1305. direct access method and falls back to the BIOS if that doesn't
  1306. work. If unsure, go with the default, which is "Any".
  1307. config PCI_GOBIOS
  1308. bool "BIOS"
  1309. config PCI_GOMMCONFIG
  1310. bool "MMConfig"
  1311. config PCI_GODIRECT
  1312. bool "Direct"
  1313. config PCI_GOOLPC
  1314. bool "OLPC"
  1315. depends on OLPC
  1316. config PCI_GOANY
  1317. bool "Any"
  1318. endchoice
  1319. config PCI_BIOS
  1320. def_bool y
  1321. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1322. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1323. config PCI_DIRECT
  1324. def_bool y
  1325. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1326. config PCI_MMCONFIG
  1327. def_bool y
  1328. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1329. config PCI_OLPC
  1330. def_bool y
  1331. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1332. config PCI_DOMAINS
  1333. def_bool y
  1334. depends on PCI
  1335. config PCI_MMCONFIG
  1336. bool "Support mmconfig PCI config space access"
  1337. depends on X86_64 && PCI && ACPI
  1338. config DMAR
  1339. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1340. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1341. help
  1342. DMA remapping (DMAR) devices support enables independent address
  1343. translations for Direct Memory Access (DMA) from devices.
  1344. These DMA remapping devices are reported via ACPI tables
  1345. and include PCI device scope covered by these DMA
  1346. remapping devices.
  1347. config DMAR_GFX_WA
  1348. def_bool y
  1349. prompt "Support for Graphics workaround"
  1350. depends on DMAR
  1351. help
  1352. Current Graphics drivers tend to use physical address
  1353. for DMA and avoid using DMA APIs. Setting this config
  1354. option permits the IOMMU driver to set a unity map for
  1355. all the OS-visible memory. Hence the driver can continue
  1356. to use physical addresses for DMA.
  1357. config DMAR_FLOPPY_WA
  1358. def_bool y
  1359. depends on DMAR
  1360. help
  1361. Floppy disk drivers are know to bypass DMA API calls
  1362. thereby failing to work when IOMMU is enabled. This
  1363. workaround will setup a 1:1 mapping for the first
  1364. 16M to make floppy (an ISA device) work.
  1365. source "drivers/pci/pcie/Kconfig"
  1366. source "drivers/pci/Kconfig"
  1367. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1368. config ISA_DMA_API
  1369. def_bool y
  1370. if X86_32
  1371. config ISA
  1372. bool "ISA support"
  1373. depends on !X86_VOYAGER
  1374. help
  1375. Find out whether you have ISA slots on your motherboard. ISA is the
  1376. name of a bus system, i.e. the way the CPU talks to the other stuff
  1377. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1378. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1379. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1380. config EISA
  1381. bool "EISA support"
  1382. depends on ISA
  1383. ---help---
  1384. The Extended Industry Standard Architecture (EISA) bus was
  1385. developed as an open alternative to the IBM MicroChannel bus.
  1386. The EISA bus provided some of the features of the IBM MicroChannel
  1387. bus while maintaining backward compatibility with cards made for
  1388. the older ISA bus. The EISA bus saw limited use between 1988 and
  1389. 1995 when it was made obsolete by the PCI bus.
  1390. Say Y here if you are building a kernel for an EISA-based machine.
  1391. Otherwise, say N.
  1392. source "drivers/eisa/Kconfig"
  1393. config MCA
  1394. bool "MCA support" if !X86_VOYAGER
  1395. default y if X86_VOYAGER
  1396. help
  1397. MicroChannel Architecture is found in some IBM PS/2 machines and
  1398. laptops. It is a bus system similar to PCI or ISA. See
  1399. <file:Documentation/mca.txt> (and especially the web page given
  1400. there) before attempting to build an MCA bus kernel.
  1401. source "drivers/mca/Kconfig"
  1402. config SCx200
  1403. tristate "NatSemi SCx200 support"
  1404. depends on !X86_VOYAGER
  1405. help
  1406. This provides basic support for National Semiconductor's
  1407. (now AMD's) Geode processors. The driver probes for the
  1408. PCI-IDs of several on-chip devices, so its a good dependency
  1409. for other scx200_* drivers.
  1410. If compiled as a module, the driver is named scx200.
  1411. config SCx200HR_TIMER
  1412. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1413. depends on SCx200 && GENERIC_TIME
  1414. default y
  1415. help
  1416. This driver provides a clocksource built upon the on-chip
  1417. 27MHz high-resolution timer. Its also a workaround for
  1418. NSC Geode SC-1100's buggy TSC, which loses time when the
  1419. processor goes idle (as is done by the scheduler). The
  1420. other workaround is idle=poll boot option.
  1421. config GEODE_MFGPT_TIMER
  1422. def_bool y
  1423. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1424. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1425. help
  1426. This driver provides a clock event source based on the MFGPT
  1427. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1428. MFGPTs have a better resolution and max interval than the
  1429. generic PIT, and are suitable for use as high-res timers.
  1430. config OLPC
  1431. bool "One Laptop Per Child support"
  1432. default n
  1433. help
  1434. Add support for detecting the unique features of the OLPC
  1435. XO hardware.
  1436. endif # X86_32
  1437. config K8_NB
  1438. def_bool y
  1439. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1440. source "drivers/pcmcia/Kconfig"
  1441. source "drivers/pci/hotplug/Kconfig"
  1442. endmenu
  1443. menu "Executable file formats / Emulations"
  1444. source "fs/Kconfig.binfmt"
  1445. config IA32_EMULATION
  1446. bool "IA32 Emulation"
  1447. depends on X86_64
  1448. select COMPAT_BINFMT_ELF
  1449. help
  1450. Include code to run 32-bit programs under a 64-bit kernel. You should
  1451. likely turn this on, unless you're 100% sure that you don't have any
  1452. 32-bit programs left.
  1453. config IA32_AOUT
  1454. tristate "IA32 a.out support"
  1455. depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
  1456. help
  1457. Support old a.out binaries in the 32bit emulation.
  1458. config COMPAT
  1459. def_bool y
  1460. depends on IA32_EMULATION
  1461. config COMPAT_FOR_U64_ALIGNMENT
  1462. def_bool COMPAT
  1463. depends on X86_64
  1464. config SYSVIPC_COMPAT
  1465. def_bool y
  1466. depends on X86_64 && COMPAT && SYSVIPC
  1467. endmenu
  1468. source "net/Kconfig"
  1469. source "drivers/Kconfig"
  1470. source "drivers/firmware/Kconfig"
  1471. source "fs/Kconfig"
  1472. source "arch/x86/Kconfig.debug"
  1473. source "security/Kconfig"
  1474. source "crypto/Kconfig"
  1475. source "arch/x86/kvm/Kconfig"
  1476. source "lib/Kconfig"