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_IOREMAP_PROT
  21. select HAVE_GET_USER_PAGES_FAST
  22. select HAVE_KPROBES
  23. select ARCH_WANT_OPTIONAL_GPIOLIB if !X86_RDC321X
  24. select HAVE_KRETPROBES
  25. select HAVE_DYNAMIC_FTRACE
  26. select HAVE_FTRACE
  27. select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
  28. select HAVE_ARCH_KGDB if !X86_VOYAGER
  29. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  30. config ARCH_DEFCONFIG
  31. string
  32. default "arch/x86/configs/i386_defconfig" if X86_32
  33. default "arch/x86/configs/x86_64_defconfig" if X86_64
  34. config GENERIC_LOCKBREAK
  35. def_bool n
  36. config GENERIC_TIME
  37. def_bool y
  38. config GENERIC_CMOS_UPDATE
  39. def_bool y
  40. config CLOCKSOURCE_WATCHDOG
  41. def_bool y
  42. config GENERIC_CLOCKEVENTS
  43. def_bool y
  44. config GENERIC_CLOCKEVENTS_BROADCAST
  45. def_bool y
  46. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  47. config LOCKDEP_SUPPORT
  48. def_bool y
  49. config STACKTRACE_SUPPORT
  50. def_bool y
  51. config HAVE_LATENCYTOP_SUPPORT
  52. def_bool y
  53. config FAST_CMPXCHG_LOCAL
  54. bool
  55. default y
  56. config MMU
  57. def_bool y
  58. config ZONE_DMA
  59. def_bool y
  60. config SBUS
  61. bool
  62. config GENERIC_ISA_DMA
  63. def_bool y
  64. config GENERIC_IOMAP
  65. def_bool y
  66. config GENERIC_BUG
  67. def_bool y
  68. depends on BUG
  69. config GENERIC_HWEIGHT
  70. def_bool y
  71. config GENERIC_GPIO
  72. def_bool n
  73. config ARCH_MAY_HAVE_PC_FDC
  74. def_bool y
  75. config RWSEM_GENERIC_SPINLOCK
  76. def_bool !X86_XADD
  77. config RWSEM_XCHGADD_ALGORITHM
  78. def_bool X86_XADD
  79. config ARCH_HAS_ILOG2_U32
  80. def_bool n
  81. config ARCH_HAS_ILOG2_U64
  82. def_bool n
  83. config ARCH_HAS_CPU_IDLE_WAIT
  84. def_bool y
  85. config GENERIC_CALIBRATE_DELAY
  86. def_bool y
  87. config GENERIC_TIME_VSYSCALL
  88. bool
  89. default X86_64
  90. config ARCH_HAS_CPU_RELAX
  91. def_bool y
  92. config ARCH_HAS_CACHE_LINE_SIZE
  93. def_bool y
  94. config HAVE_SETUP_PER_CPU_AREA
  95. def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
  96. config HAVE_CPUMASK_OF_CPU_MAP
  97. def_bool X86_64_SMP
  98. config ARCH_HIBERNATION_POSSIBLE
  99. def_bool y
  100. depends on !SMP || !X86_VOYAGER
  101. config ARCH_SUSPEND_POSSIBLE
  102. def_bool y
  103. depends on !X86_VOYAGER
  104. config ZONE_DMA32
  105. bool
  106. default X86_64
  107. config ARCH_POPULATES_NODE_MAP
  108. def_bool y
  109. config AUDIT_ARCH
  110. bool
  111. default X86_64
  112. config ARCH_SUPPORTS_AOUT
  113. def_bool y
  114. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  115. def_bool y
  116. # Use the generic interrupt handling code in kernel/irq/:
  117. config GENERIC_HARDIRQS
  118. bool
  119. default y
  120. config GENERIC_IRQ_PROBE
  121. bool
  122. default y
  123. config GENERIC_PENDING_IRQ
  124. bool
  125. depends on GENERIC_HARDIRQS && SMP
  126. default y
  127. config X86_SMP
  128. bool
  129. depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
  130. select USE_GENERIC_SMP_HELPERS
  131. default y
  132. config X86_32_SMP
  133. def_bool y
  134. depends on X86_32 && SMP
  135. config X86_64_SMP
  136. def_bool y
  137. depends on X86_64 && SMP
  138. config X86_HT
  139. bool
  140. depends on SMP
  141. depends on (X86_32 && !X86_VOYAGER) || X86_64
  142. default y
  143. config X86_BIOS_REBOOT
  144. bool
  145. depends on !X86_VOYAGER
  146. default y
  147. config X86_TRAMPOLINE
  148. bool
  149. depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
  150. default y
  151. config KTIME_SCALAR
  152. def_bool X86_32
  153. source "init/Kconfig"
  154. menu "Processor type and features"
  155. source "kernel/time/Kconfig"
  156. config SMP
  157. bool "Symmetric multi-processing support"
  158. ---help---
  159. This enables support for systems with more than one CPU. If you have
  160. a system with only one CPU, like most personal computers, say N. If
  161. you have a system with more than one CPU, say Y.
  162. If you say N here, the kernel will run on single and multiprocessor
  163. machines, but will use only one CPU of a multiprocessor machine. If
  164. you say Y here, the kernel will run on many, but not all,
  165. singleprocessor machines. On a singleprocessor machine, the kernel
  166. will run faster if you say N here.
  167. Note that if you say Y here and choose architecture "586" or
  168. "Pentium" under "Processor family", the kernel will not work on 486
  169. architectures. Similarly, multiprocessor kernels for the "PPro"
  170. architecture may not work on all Pentium based boards.
  171. People using multiprocessor machines who say Y here should also say
  172. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  173. Management" code will be disabled if you say Y here.
  174. See also <file:Documentation/i386/IO-APIC.txt>,
  175. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  176. <http://www.tldp.org/docs.html#howto>.
  177. If you don't know what to do here, say N.
  178. config X86_FIND_SMP_CONFIG
  179. def_bool y
  180. depends on X86_MPPARSE || X86_VOYAGER
  181. if ACPI
  182. config X86_MPPARSE
  183. def_bool y
  184. bool "Enable MPS table"
  185. depends on X86_LOCAL_APIC
  186. help
  187. For old smp systems that do not have proper acpi support. Newer systems
  188. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  189. endif
  190. if !ACPI
  191. config X86_MPPARSE
  192. def_bool y
  193. depends on X86_LOCAL_APIC
  194. endif
  195. choice
  196. prompt "Subarchitecture Type"
  197. default X86_PC
  198. config X86_PC
  199. bool "PC-compatible"
  200. help
  201. Choose this option if your computer is a standard PC or compatible.
  202. config X86_ELAN
  203. bool "AMD Elan"
  204. depends on X86_32
  205. help
  206. Select this for an AMD Elan processor.
  207. Do not use this option for K6/Athlon/Opteron processors!
  208. If unsure, choose "PC-compatible" instead.
  209. config X86_VOYAGER
  210. bool "Voyager (NCR)"
  211. depends on X86_32 && (SMP || BROKEN) && !PCI
  212. help
  213. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  214. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  215. *** WARNING ***
  216. If you do not specifically know you have a Voyager based machine,
  217. say N here, otherwise the kernel you build will not be bootable.
  218. config X86_GENERICARCH
  219. bool "Generic architecture"
  220. depends on X86_32
  221. help
  222. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  223. subarchitectures. It is intended for a generic binary kernel.
  224. if you select them all, kernel will probe it one by one. and will
  225. fallback to default.
  226. if X86_GENERICARCH
  227. config X86_NUMAQ
  228. bool "NUMAQ (IBM/Sequent)"
  229. depends on SMP && X86_32 && PCI && X86_MPPARSE
  230. select NUMA
  231. help
  232. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  233. NUMA multiquad box. This changes the way that processors are
  234. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  235. of Flat Logical. You will need a new lynxer.elf file to flash your
  236. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  237. config X86_SUMMIT
  238. bool "Summit/EXA (IBM x440)"
  239. depends on X86_32 && SMP
  240. help
  241. This option is needed for IBM systems that use the Summit/EXA chipset.
  242. In particular, it is needed for the x440.
  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. config X86_BIGSMP
  250. bool "Support for big SMP systems with more than 8 CPUs"
  251. depends on X86_32 && SMP
  252. help
  253. This option is needed for the systems that have more than 8 CPUs
  254. and if the system is not of any sub-arch type above.
  255. endif
  256. config X86_RDC321X
  257. bool "RDC R-321x SoC"
  258. depends on X86_32
  259. select M486
  260. select X86_REBOOTFIXUPS
  261. select GENERIC_GPIO
  262. select LEDS_CLASS
  263. select LEDS_GPIO
  264. select NEW_LEDS
  265. help
  266. This option is needed for RDC R-321x system-on-chip, also known
  267. as R-8610-(G).
  268. If you don't have one of these chips, you should say N here.
  269. config X86_VSMP
  270. bool "Support for ScaleMP vSMP"
  271. select PARAVIRT
  272. depends on X86_64 && PCI
  273. help
  274. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  275. supposed to run on these EM64T-based machines. Only choose this option
  276. if you have one of these machines.
  277. endchoice
  278. config X86_VISWS
  279. bool "SGI 320/540 (Visual Workstation)"
  280. depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
  281. help
  282. The SGI Visual Workstation series is an IA32-based workstation
  283. based on SGI systems chips with some legacy PC hardware attached.
  284. Say Y here to create a kernel to run on the SGI 320 or 540.
  285. A kernel compiled for the Visual Workstation will run on general
  286. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  287. config SCHED_NO_NO_OMIT_FRAME_POINTER
  288. def_bool y
  289. prompt "Single-depth WCHAN output"
  290. depends on X86_32
  291. help
  292. Calculate simpler /proc/<PID>/wchan values. If this option
  293. is disabled then wchan values will recurse back to the
  294. caller function. This provides more accurate wchan values,
  295. at the expense of slightly more scheduling overhead.
  296. If in doubt, say "Y".
  297. menuconfig PARAVIRT_GUEST
  298. bool "Paravirtualized guest support"
  299. help
  300. Say Y here to get to see options related to running Linux under
  301. various hypervisors. This option alone does not add any kernel code.
  302. If you say N, all options in this submenu will be skipped and disabled.
  303. if PARAVIRT_GUEST
  304. source "arch/x86/xen/Kconfig"
  305. config VMI
  306. bool "VMI Guest support"
  307. select PARAVIRT
  308. depends on X86_32
  309. depends on !X86_VOYAGER
  310. help
  311. VMI provides a paravirtualized interface to the VMware ESX server
  312. (it could be used by other hypervisors in theory too, but is not
  313. at the moment), by linking the kernel to a GPL-ed ROM module
  314. provided by the hypervisor.
  315. config KVM_CLOCK
  316. bool "KVM paravirtualized clock"
  317. select PARAVIRT
  318. select PARAVIRT_CLOCK
  319. depends on !X86_VOYAGER
  320. help
  321. Turning on this option will allow you to run a paravirtualized clock
  322. when running over the KVM hypervisor. Instead of relying on a PIT
  323. (or probably other) emulation by the underlying device model, the host
  324. provides the guest with timing infrastructure such as time of day, and
  325. system time
  326. config KVM_GUEST
  327. bool "KVM Guest support"
  328. select PARAVIRT
  329. depends on !X86_VOYAGER
  330. help
  331. This option enables various optimizations for running under the KVM
  332. hypervisor.
  333. source "arch/x86/lguest/Kconfig"
  334. config PARAVIRT
  335. bool "Enable paravirtualization code"
  336. depends on !X86_VOYAGER
  337. help
  338. This changes the kernel so it can modify itself when it is run
  339. under a hypervisor, potentially improving performance significantly
  340. over full virtualization. However, when run without a hypervisor
  341. the kernel is theoretically slower and slightly larger.
  342. config PARAVIRT_CLOCK
  343. bool
  344. default n
  345. endif
  346. config PARAVIRT_DEBUG
  347. bool "paravirt-ops debugging"
  348. depends on PARAVIRT && DEBUG_KERNEL
  349. help
  350. Enable to debug paravirt_ops internals. Specifically, BUG if
  351. a paravirt_op is missing when it is called.
  352. config MEMTEST
  353. bool "Memtest"
  354. help
  355. This option adds a kernel parameter 'memtest', which allows memtest
  356. to be set.
  357. memtest=0, mean disabled; -- default
  358. memtest=1, mean do 1 test pattern;
  359. ...
  360. memtest=4, mean do 4 test patterns.
  361. If you are unsure how to answer this question, answer N.
  362. config X86_SUMMIT_NUMA
  363. def_bool y
  364. depends on X86_32 && NUMA && X86_GENERICARCH
  365. config X86_CYCLONE_TIMER
  366. def_bool y
  367. depends on X86_GENERICARCH
  368. config ES7000_CLUSTERED_APIC
  369. def_bool y
  370. depends on SMP && X86_ES7000 && MPENTIUMIII
  371. source "arch/x86/Kconfig.cpu"
  372. config HPET_TIMER
  373. def_bool X86_64
  374. prompt "HPET Timer Support" if X86_32
  375. help
  376. Use the IA-PC HPET (High Precision Event Timer) to manage
  377. time in preference to the PIT and RTC, if a HPET is
  378. present.
  379. HPET is the next generation timer replacing legacy 8254s.
  380. The HPET provides a stable time base on SMP
  381. systems, unlike the TSC, but it is more expensive to access,
  382. as it is off-chip. You can find the HPET spec at
  383. <http://www.intel.com/hardwaredesign/hpetspec.htm>.
  384. You can safely choose Y here. However, HPET will only be
  385. activated if the platform and the BIOS support this feature.
  386. Otherwise the 8254 will be used for timing services.
  387. Choose N to continue using the legacy 8254 timer.
  388. config HPET_EMULATE_RTC
  389. def_bool y
  390. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  391. # Mark as embedded because too many people got it wrong.
  392. # The code disables itself when not needed.
  393. config DMI
  394. default y
  395. bool "Enable DMI scanning" if EMBEDDED
  396. help
  397. Enabled scanning of DMI to identify machine quirks. Say Y
  398. here unless you have verified that your setup is not
  399. affected by entries in the DMI blacklist. Required by PNP
  400. BIOS code.
  401. config GART_IOMMU
  402. bool "GART IOMMU support" if EMBEDDED
  403. default y
  404. select SWIOTLB
  405. select AGP
  406. depends on X86_64 && PCI
  407. help
  408. Support for full DMA access of devices with 32bit memory access only
  409. on systems with more than 3GB. This is usually needed for USB,
  410. sound, many IDE/SATA chipsets and some other devices.
  411. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  412. based hardware IOMMU and a software bounce buffer based IOMMU used
  413. on Intel systems and as fallback.
  414. The code is only active when needed (enough memory and limited
  415. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  416. too.
  417. config CALGARY_IOMMU
  418. bool "IBM Calgary IOMMU support"
  419. select SWIOTLB
  420. depends on X86_64 && PCI && EXPERIMENTAL
  421. help
  422. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  423. systems. Needed to run systems with more than 3GB of memory
  424. properly with 32-bit PCI devices that do not support DAC
  425. (Double Address Cycle). Calgary also supports bus level
  426. isolation, where all DMAs pass through the IOMMU. This
  427. prevents them from going anywhere except their intended
  428. destination. This catches hard-to-find kernel bugs and
  429. mis-behaving drivers and devices that do not use the DMA-API
  430. properly to set up their DMA buffers. The IOMMU can be
  431. turned off at boot time with the iommu=off parameter.
  432. Normally the kernel will make the right choice by itself.
  433. If unsure, say Y.
  434. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  435. def_bool y
  436. prompt "Should Calgary be enabled by default?"
  437. depends on CALGARY_IOMMU
  438. help
  439. Should Calgary be enabled by default? if you choose 'y', Calgary
  440. will be used (if it exists). If you choose 'n', Calgary will not be
  441. used even if it exists. If you choose 'n' and would like to use
  442. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  443. If unsure, say Y.
  444. config AMD_IOMMU
  445. bool "AMD IOMMU support"
  446. select SWIOTLB
  447. depends on X86_64 && PCI && ACPI
  448. help
  449. With this option you can enable support for AMD IOMMU hardware in
  450. your system. An IOMMU is a hardware component which provides
  451. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  452. can isolate the the DMA memory of different devices and protect the
  453. system from misbehaving device drivers or hardware.
  454. You can find out if your system has an AMD IOMMU if you look into
  455. your BIOS for an option to enable it or if you have an IVRS ACPI
  456. table.
  457. # need this always selected by IOMMU for the VIA workaround
  458. config SWIOTLB
  459. bool
  460. help
  461. Support for software bounce buffers used on x86-64 systems
  462. which don't have a hardware IOMMU (e.g. the current generation
  463. of Intel's x86-64 CPUs). Using this PCI devices which can only
  464. access 32-bits of memory can be used on systems with more than
  465. 3 GB of memory. If unsure, say Y.
  466. config IOMMU_HELPER
  467. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  468. config MAXSMP
  469. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  470. depends on X86_64 && SMP
  471. default n
  472. help
  473. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  474. If unsure, say N.
  475. if MAXSMP
  476. config NR_CPUS
  477. int
  478. default "4096"
  479. endif
  480. if !MAXSMP
  481. config NR_CPUS
  482. int "Maximum number of CPUs (2-4096)"
  483. range 2 4096
  484. depends on SMP
  485. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  486. default "8"
  487. help
  488. This allows you to specify the maximum number of CPUs which this
  489. kernel will support. The maximum supported value is 4096 and the
  490. minimum value which makes sense is 2.
  491. This is purely to save memory - each supported CPU adds
  492. approximately eight kilobytes to the kernel image.
  493. endif
  494. config SCHED_SMT
  495. bool "SMT (Hyperthreading) scheduler support"
  496. depends on X86_HT
  497. help
  498. SMT scheduler support improves the CPU scheduler's decision making
  499. when dealing with Intel Pentium 4 chips with HyperThreading at a
  500. cost of slightly increased overhead in some places. If unsure say
  501. N here.
  502. config SCHED_MC
  503. def_bool y
  504. prompt "Multi-core scheduler support"
  505. depends on X86_HT
  506. help
  507. Multi-core scheduler support improves the CPU scheduler's decision
  508. making when dealing with multi-core CPU chips at a cost of slightly
  509. increased overhead in some places. If unsure say N here.
  510. source "kernel/Kconfig.preempt"
  511. config X86_UP_APIC
  512. bool "Local APIC support on uniprocessors"
  513. depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
  514. help
  515. A local APIC (Advanced Programmable Interrupt Controller) is an
  516. integrated interrupt controller in the CPU. If you have a single-CPU
  517. system which has a processor with a local APIC, you can say Y here to
  518. enable and use it. If you say Y here even though your machine doesn't
  519. have a local APIC, then the kernel will still run with no slowdown at
  520. all. The local APIC supports CPU-generated self-interrupts (timer,
  521. performance counters), and the NMI watchdog which detects hard
  522. lockups.
  523. config X86_UP_IOAPIC
  524. bool "IO-APIC support on uniprocessors"
  525. depends on X86_UP_APIC
  526. help
  527. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  528. SMP-capable replacement for PC-style interrupt controllers. Most
  529. SMP systems and many recent uniprocessor systems have one.
  530. If you have a single-CPU system with an IO-APIC, you can say Y here
  531. to use it. If you say Y here even though your machine doesn't have
  532. an IO-APIC, then the kernel will still run with no slowdown at all.
  533. config X86_LOCAL_APIC
  534. def_bool y
  535. depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
  536. config X86_IO_APIC
  537. def_bool y
  538. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
  539. config X86_VISWS_APIC
  540. def_bool y
  541. depends on X86_32 && X86_VISWS
  542. config X86_MCE
  543. bool "Machine Check Exception"
  544. depends on !X86_VOYAGER
  545. ---help---
  546. Machine Check Exception support allows the processor to notify the
  547. kernel if it detects a problem (e.g. overheating, component failure).
  548. The action the kernel takes depends on the severity of the problem,
  549. ranging from a warning message on the console, to halting the machine.
  550. Your processor must be a Pentium or newer to support this - check the
  551. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  552. have a design flaw which leads to false MCE events - hence MCE is
  553. disabled on all P5 processors, unless explicitly enabled with "mce"
  554. as a boot argument. Similarly, if MCE is built in and creates a
  555. problem on some new non-standard machine, you can boot with "nomce"
  556. to disable it. MCE support simply ignores non-MCE processors like
  557. the 386 and 486, so nearly everyone can say Y here.
  558. config X86_MCE_INTEL
  559. def_bool y
  560. prompt "Intel MCE features"
  561. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  562. help
  563. Additional support for intel specific MCE features such as
  564. the thermal monitor.
  565. config X86_MCE_AMD
  566. def_bool y
  567. prompt "AMD MCE features"
  568. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  569. help
  570. Additional support for AMD specific MCE features such as
  571. the DRAM Error Threshold.
  572. config X86_MCE_NONFATAL
  573. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  574. depends on X86_32 && X86_MCE
  575. help
  576. Enabling this feature starts a timer that triggers every 5 seconds which
  577. will look at the machine check registers to see if anything happened.
  578. Non-fatal problems automatically get corrected (but still logged).
  579. Disable this if you don't want to see these messages.
  580. Seeing the messages this option prints out may be indicative of dying
  581. or out-of-spec (ie, overclocked) hardware.
  582. This option only does something on certain CPUs.
  583. (AMD Athlon/Duron and Intel Pentium 4)
  584. config X86_MCE_P4THERMAL
  585. bool "check for P4 thermal throttling interrupt."
  586. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
  587. help
  588. Enabling this feature will cause a message to be printed when the P4
  589. enters thermal throttling.
  590. config VM86
  591. bool "Enable VM86 support" if EMBEDDED
  592. default y
  593. depends on X86_32
  594. help
  595. This option is required by programs like DOSEMU to run 16-bit legacy
  596. code on X86 processors. It also may be needed by software like
  597. XFree86 to initialize some video cards via BIOS. Disabling this
  598. option saves about 6k.
  599. config TOSHIBA
  600. tristate "Toshiba Laptop support"
  601. depends on X86_32
  602. ---help---
  603. This adds a driver to safely access the System Management Mode of
  604. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  605. not work on models with a Phoenix BIOS. The System Management Mode
  606. is used to set the BIOS and power saving options on Toshiba portables.
  607. For information on utilities to make use of this driver see the
  608. Toshiba Linux utilities web site at:
  609. <http://www.buzzard.org.uk/toshiba/>.
  610. Say Y if you intend to run this kernel on a Toshiba portable.
  611. Say N otherwise.
  612. config I8K
  613. tristate "Dell laptop support"
  614. ---help---
  615. This adds a driver to safely access the System Management Mode
  616. of the CPU on the Dell Inspiron 8000. The System Management Mode
  617. is used to read cpu temperature and cooling fan status and to
  618. control the fans on the I8K portables.
  619. This driver has been tested only on the Inspiron 8000 but it may
  620. also work with other Dell laptops. You can force loading on other
  621. models by passing the parameter `force=1' to the module. Use at
  622. your own risk.
  623. For information on utilities to make use of this driver see the
  624. I8K Linux utilities web site at:
  625. <http://people.debian.org/~dz/i8k/>
  626. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  627. Say N otherwise.
  628. config X86_REBOOTFIXUPS
  629. def_bool n
  630. prompt "Enable X86 board specific fixups for reboot"
  631. depends on X86_32 && X86
  632. ---help---
  633. This enables chipset and/or board specific fixups to be done
  634. in order to get reboot to work correctly. This is only needed on
  635. some combinations of hardware and BIOS. The symptom, for which
  636. this config is intended, is when reboot ends with a stalled/hung
  637. system.
  638. Currently, the only fixup is for the Geode machines using
  639. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  640. Say Y if you want to enable the fixup. Currently, it's safe to
  641. enable this option even if you don't need it.
  642. Say N otherwise.
  643. config MICROCODE
  644. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  645. select FW_LOADER
  646. ---help---
  647. If you say Y here, you will be able to update the microcode on
  648. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  649. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  650. actual microcode binary data itself which is not shipped with the
  651. Linux kernel.
  652. For latest news and information on obtaining all the required
  653. ingredients for this driver, check:
  654. <http://www.urbanmyth.org/microcode/>.
  655. To compile this driver as a module, choose M here: the
  656. module will be called microcode.
  657. config MICROCODE_OLD_INTERFACE
  658. def_bool y
  659. depends on MICROCODE
  660. config X86_MSR
  661. tristate "/dev/cpu/*/msr - Model-specific register support"
  662. help
  663. This device gives privileged processes access to the x86
  664. Model-Specific Registers (MSRs). It is a character device with
  665. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  666. MSR accesses are directed to a specific CPU on multi-processor
  667. systems.
  668. config X86_CPUID
  669. tristate "/dev/cpu/*/cpuid - CPU information support"
  670. help
  671. This device gives processes access to the x86 CPUID instruction to
  672. be executed on a specific processor. It is a character device
  673. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  674. /dev/cpu/31/cpuid.
  675. choice
  676. prompt "High Memory Support"
  677. default HIGHMEM4G if !X86_NUMAQ
  678. default HIGHMEM64G if X86_NUMAQ
  679. depends on X86_32
  680. config NOHIGHMEM
  681. bool "off"
  682. depends on !X86_NUMAQ
  683. ---help---
  684. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  685. However, the address space of 32-bit x86 processors is only 4
  686. Gigabytes large. That means that, if you have a large amount of
  687. physical memory, not all of it can be "permanently mapped" by the
  688. kernel. The physical memory that's not permanently mapped is called
  689. "high memory".
  690. If you are compiling a kernel which will never run on a machine with
  691. more than 1 Gigabyte total physical RAM, answer "off" here (default
  692. choice and suitable for most users). This will result in a "3GB/1GB"
  693. split: 3GB are mapped so that each process sees a 3GB virtual memory
  694. space and the remaining part of the 4GB virtual memory space is used
  695. by the kernel to permanently map as much physical memory as
  696. possible.
  697. If the machine has between 1 and 4 Gigabytes physical RAM, then
  698. answer "4GB" here.
  699. If more than 4 Gigabytes is used then answer "64GB" here. This
  700. selection turns Intel PAE (Physical Address Extension) mode on.
  701. PAE implements 3-level paging on IA32 processors. PAE is fully
  702. supported by Linux, PAE mode is implemented on all recent Intel
  703. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  704. then the kernel will not boot on CPUs that don't support PAE!
  705. The actual amount of total physical memory will either be
  706. auto detected or can be forced by using a kernel command line option
  707. such as "mem=256M". (Try "man bootparam" or see the documentation of
  708. your boot loader (lilo or loadlin) about how to pass options to the
  709. kernel at boot time.)
  710. If unsure, say "off".
  711. config HIGHMEM4G
  712. bool "4GB"
  713. depends on !X86_NUMAQ
  714. help
  715. Select this if you have a 32-bit processor and between 1 and 4
  716. gigabytes of physical RAM.
  717. config HIGHMEM64G
  718. bool "64GB"
  719. depends on !M386 && !M486
  720. select X86_PAE
  721. help
  722. Select this if you have a 32-bit processor and more than 4
  723. gigabytes of physical RAM.
  724. endchoice
  725. choice
  726. depends on EXPERIMENTAL
  727. prompt "Memory split" if EMBEDDED
  728. default VMSPLIT_3G
  729. depends on X86_32
  730. help
  731. Select the desired split between kernel and user memory.
  732. If the address range available to the kernel is less than the
  733. physical memory installed, the remaining memory will be available
  734. as "high memory". Accessing high memory is a little more costly
  735. than low memory, as it needs to be mapped into the kernel first.
  736. Note that increasing the kernel address space limits the range
  737. available to user programs, making the address space there
  738. tighter. Selecting anything other than the default 3G/1G split
  739. will also likely make your kernel incompatible with binary-only
  740. kernel modules.
  741. If you are not absolutely sure what you are doing, leave this
  742. option alone!
  743. config VMSPLIT_3G
  744. bool "3G/1G user/kernel split"
  745. config VMSPLIT_3G_OPT
  746. depends on !X86_PAE
  747. bool "3G/1G user/kernel split (for full 1G low memory)"
  748. config VMSPLIT_2G
  749. bool "2G/2G user/kernel split"
  750. config VMSPLIT_2G_OPT
  751. depends on !X86_PAE
  752. bool "2G/2G user/kernel split (for full 2G low memory)"
  753. config VMSPLIT_1G
  754. bool "1G/3G user/kernel split"
  755. endchoice
  756. config PAGE_OFFSET
  757. hex
  758. default 0xB0000000 if VMSPLIT_3G_OPT
  759. default 0x80000000 if VMSPLIT_2G
  760. default 0x78000000 if VMSPLIT_2G_OPT
  761. default 0x40000000 if VMSPLIT_1G
  762. default 0xC0000000
  763. depends on X86_32
  764. config HIGHMEM
  765. def_bool y
  766. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  767. config X86_PAE
  768. def_bool n
  769. prompt "PAE (Physical Address Extension) Support"
  770. depends on X86_32 && !HIGHMEM4G
  771. select RESOURCES_64BIT
  772. help
  773. PAE is required for NX support, and furthermore enables
  774. larger swapspace support for non-overcommit purposes. It
  775. has the cost of more pagetable lookup overhead, and also
  776. consumes more pagetable space per process.
  777. # Common NUMA Features
  778. config NUMA
  779. bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
  780. depends on SMP
  781. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  782. default n if X86_PC
  783. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  784. help
  785. Enable NUMA (Non Uniform Memory Access) support.
  786. The kernel will try to allocate memory used by a CPU on the
  787. local memory controller of the CPU and add some more
  788. NUMA awareness to the kernel.
  789. For i386 this is currently highly experimental and should be only
  790. used for kernel development. It might also cause boot failures.
  791. For x86_64 this is recommended on all multiprocessor Opteron systems.
  792. If the system is EM64T, you should say N unless your system is
  793. EM64T NUMA.
  794. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  795. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  796. config K8_NUMA
  797. def_bool y
  798. prompt "Old style AMD Opteron NUMA detection"
  799. depends on X86_64 && NUMA && PCI
  800. help
  801. Enable K8 NUMA node topology detection. You should say Y here if
  802. you have a multi processor AMD K8 system. This uses an old
  803. method to read the NUMA configuration directly from the builtin
  804. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  805. instead, which also takes priority if both are compiled in.
  806. config X86_64_ACPI_NUMA
  807. def_bool y
  808. prompt "ACPI NUMA detection"
  809. depends on X86_64 && NUMA && ACPI && PCI
  810. select ACPI_NUMA
  811. help
  812. Enable ACPI SRAT based node topology detection.
  813. # Some NUMA nodes have memory ranges that span
  814. # other nodes. Even though a pfn is valid and
  815. # between a node's start and end pfns, it may not
  816. # reside on that node. See memmap_init_zone()
  817. # for details.
  818. config NODES_SPAN_OTHER_NODES
  819. def_bool y
  820. depends on X86_64_ACPI_NUMA
  821. config NUMA_EMU
  822. bool "NUMA emulation"
  823. depends on X86_64 && NUMA
  824. help
  825. Enable NUMA emulation. A flat machine will be split
  826. into virtual nodes when booted with "numa=fake=N", where N is the
  827. number of nodes. This is only useful for debugging.
  828. if MAXSMP
  829. config NODES_SHIFT
  830. int
  831. default "9"
  832. endif
  833. if !MAXSMP
  834. config NODES_SHIFT
  835. int "Maximum NUMA Nodes (as a power of 2)"
  836. range 1 9 if X86_64
  837. default "6" if X86_64
  838. default "4" if X86_NUMAQ
  839. default "3"
  840. depends on NEED_MULTIPLE_NODES
  841. help
  842. Specify the maximum number of NUMA Nodes available on the target
  843. system. Increases memory reserved to accomodate various tables.
  844. endif
  845. config HAVE_ARCH_BOOTMEM_NODE
  846. def_bool y
  847. depends on X86_32 && NUMA
  848. config ARCH_HAVE_MEMORY_PRESENT
  849. def_bool y
  850. depends on X86_32 && DISCONTIGMEM
  851. config NEED_NODE_MEMMAP_SIZE
  852. def_bool y
  853. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  854. config HAVE_ARCH_ALLOC_REMAP
  855. def_bool y
  856. depends on X86_32 && NUMA
  857. config ARCH_FLATMEM_ENABLE
  858. def_bool y
  859. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
  860. config ARCH_DISCONTIGMEM_ENABLE
  861. def_bool y
  862. depends on NUMA && X86_32
  863. config ARCH_DISCONTIGMEM_DEFAULT
  864. def_bool y
  865. depends on NUMA && X86_32
  866. config ARCH_SPARSEMEM_DEFAULT
  867. def_bool y
  868. depends on X86_64
  869. config ARCH_SPARSEMEM_ENABLE
  870. def_bool y
  871. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
  872. select SPARSEMEM_STATIC if X86_32
  873. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  874. config ARCH_SELECT_MEMORY_MODEL
  875. def_bool y
  876. depends on ARCH_SPARSEMEM_ENABLE
  877. config ARCH_MEMORY_PROBE
  878. def_bool X86_64
  879. depends on MEMORY_HOTPLUG
  880. source "mm/Kconfig"
  881. config HIGHPTE
  882. bool "Allocate 3rd-level pagetables from highmem"
  883. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  884. help
  885. The VM uses one page table entry for each page of physical memory.
  886. For systems with a lot of RAM, this can be wasteful of precious
  887. low memory. Setting this option will put user-space page table
  888. entries in high memory.
  889. config MATH_EMULATION
  890. bool
  891. prompt "Math emulation" if X86_32
  892. ---help---
  893. Linux can emulate a math coprocessor (used for floating point
  894. operations) if you don't have one. 486DX and Pentium processors have
  895. a math coprocessor built in, 486SX and 386 do not, unless you added
  896. a 487DX or 387, respectively. (The messages during boot time can
  897. give you some hints here ["man dmesg"].) Everyone needs either a
  898. coprocessor or this emulation.
  899. If you don't have a math coprocessor, you need to say Y here; if you
  900. say Y here even though you have a coprocessor, the coprocessor will
  901. be used nevertheless. (This behavior can be changed with the kernel
  902. command line option "no387", which comes handy if your coprocessor
  903. is broken. Try "man bootparam" or see the documentation of your boot
  904. loader (lilo or loadlin) about how to pass options to the kernel at
  905. boot time.) This means that it is a good idea to say Y here if you
  906. intend to use this kernel on different machines.
  907. More information about the internals of the Linux math coprocessor
  908. emulation can be found in <file:arch/x86/math-emu/README>.
  909. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  910. kernel, it won't hurt.
  911. config MTRR
  912. bool "MTRR (Memory Type Range Register) support"
  913. ---help---
  914. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  915. the Memory Type Range Registers (MTRRs) may be used to control
  916. processor access to memory ranges. This is most useful if you have
  917. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  918. allows bus write transfers to be combined into a larger transfer
  919. before bursting over the PCI/AGP bus. This can increase performance
  920. of image write operations 2.5 times or more. Saying Y here creates a
  921. /proc/mtrr file which may be used to manipulate your processor's
  922. MTRRs. Typically the X server should use this.
  923. This code has a reasonably generic interface so that similar
  924. control registers on other processors can be easily supported
  925. as well:
  926. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  927. Registers (ARRs) which provide a similar functionality to MTRRs. For
  928. these, the ARRs are used to emulate the MTRRs.
  929. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  930. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  931. write-combining. All of these processors are supported by this code
  932. and it makes sense to say Y here if you have one of them.
  933. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  934. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  935. can lead to all sorts of problems, so it's good to say Y here.
  936. You can safely say Y even if your machine doesn't have MTRRs, you'll
  937. just add about 9 KB to your kernel.
  938. See <file:Documentation/mtrr.txt> for more information.
  939. config MTRR_SANITIZER
  940. bool
  941. prompt "MTRR cleanup support"
  942. depends on MTRR
  943. help
  944. Convert MTRR layout from continuous to discrete, so X drivers can
  945. add writeback entries.
  946. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  947. The largest mtrr entry size for a continous block can be set with
  948. mtrr_chunk_size.
  949. If unsure, say N.
  950. config MTRR_SANITIZER_ENABLE_DEFAULT
  951. int "MTRR cleanup enable value (0-1)"
  952. range 0 1
  953. default "0"
  954. depends on MTRR_SANITIZER
  955. help
  956. Enable mtrr cleanup default value
  957. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  958. int "MTRR cleanup spare reg num (0-7)"
  959. range 0 7
  960. default "1"
  961. depends on MTRR_SANITIZER
  962. help
  963. mtrr cleanup spare entries default, it can be changed via
  964. mtrr_spare_reg_nr=N on the kernel command line.
  965. config X86_PAT
  966. bool
  967. prompt "x86 PAT support"
  968. depends on MTRR
  969. help
  970. Use PAT attributes to setup page level cache control.
  971. PATs are the modern equivalents of MTRRs and are much more
  972. flexible than MTRRs.
  973. Say N here if you see bootup problems (boot crash, boot hang,
  974. spontaneous reboots) or a non-working video driver.
  975. If unsure, say Y.
  976. config EFI
  977. def_bool n
  978. prompt "EFI runtime service support"
  979. depends on ACPI
  980. ---help---
  981. This enables the kernel to use EFI runtime services that are
  982. available (such as the EFI variable services).
  983. This option is only useful on systems that have EFI firmware.
  984. In addition, you should use the latest ELILO loader available
  985. at <http://elilo.sourceforge.net> in order to take advantage
  986. of EFI runtime services. However, even with this option, the
  987. resultant kernel should continue to boot on existing non-EFI
  988. platforms.
  989. config IRQBALANCE
  990. def_bool y
  991. prompt "Enable kernel irq balancing"
  992. depends on X86_32 && SMP && X86_IO_APIC
  993. help
  994. The default yes will allow the kernel to do irq load balancing.
  995. Saying no will keep the kernel from doing irq load balancing.
  996. config SECCOMP
  997. def_bool y
  998. prompt "Enable seccomp to safely compute untrusted bytecode"
  999. depends on PROC_FS
  1000. help
  1001. This kernel feature is useful for number crunching applications
  1002. that may need to compute untrusted bytecode during their
  1003. execution. By using pipes or other transports made available to
  1004. the process as file descriptors supporting the read/write
  1005. syscalls, it's possible to isolate those applications in
  1006. their own address space using seccomp. Once seccomp is
  1007. enabled via /proc/<pid>/seccomp, it cannot be disabled
  1008. and the task is only allowed to execute a few safe syscalls
  1009. defined by each seccomp mode.
  1010. If unsure, say Y. Only embedded should say N here.
  1011. config CC_STACKPROTECTOR
  1012. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1013. depends on X86_64 && EXPERIMENTAL && BROKEN
  1014. help
  1015. This option turns on the -fstack-protector GCC feature. This
  1016. feature puts, at the beginning of critical functions, a canary
  1017. value on the stack just before the return address, and validates
  1018. the value just before actually returning. Stack based buffer
  1019. overflows (that need to overwrite this return address) now also
  1020. overwrite the canary, which gets detected and the attack is then
  1021. neutralized via a kernel panic.
  1022. This feature requires gcc version 4.2 or above, or a distribution
  1023. gcc with the feature backported. Older versions are automatically
  1024. detected and for those versions, this configuration option is ignored.
  1025. config CC_STACKPROTECTOR_ALL
  1026. bool "Use stack-protector for all functions"
  1027. depends on CC_STACKPROTECTOR
  1028. help
  1029. Normally, GCC only inserts the canary value protection for
  1030. functions that use large-ish on-stack buffers. By enabling
  1031. this option, GCC will be asked to do this for ALL functions.
  1032. source kernel/Kconfig.hz
  1033. config KEXEC
  1034. bool "kexec system call"
  1035. depends on X86_BIOS_REBOOT
  1036. help
  1037. kexec is a system call that implements the ability to shutdown your
  1038. current kernel, and to start another kernel. It is like a reboot
  1039. but it is independent of the system firmware. And like a reboot
  1040. you can start any kernel with it, not just Linux.
  1041. The name comes from the similarity to the exec system call.
  1042. It is an ongoing process to be certain the hardware in a machine
  1043. is properly shutdown, so do not be surprised if this code does not
  1044. initially work for you. It may help to enable device hotplugging
  1045. support. As of this writing the exact hardware interface is
  1046. strongly in flux, so no good recommendation can be made.
  1047. config CRASH_DUMP
  1048. bool "kernel crash dumps (EXPERIMENTAL)"
  1049. depends on X86_64 || (X86_32 && HIGHMEM)
  1050. help
  1051. Generate crash dump after being started by kexec.
  1052. This should be normally only set in special crash dump kernels
  1053. which are loaded in the main kernel with kexec-tools into
  1054. a specially reserved region and then later executed after
  1055. a crash by kdump/kexec. The crash dump kernel must be compiled
  1056. to a memory address not used by the main kernel or BIOS using
  1057. PHYSICAL_START, or it must be built as a relocatable image
  1058. (CONFIG_RELOCATABLE=y).
  1059. For more details see Documentation/kdump/kdump.txt
  1060. config KEXEC_JUMP
  1061. bool "kexec jump (EXPERIMENTAL)"
  1062. depends on EXPERIMENTAL
  1063. depends on KEXEC && HIBERNATION && X86_32
  1064. help
  1065. Jump between original kernel and kexeced kernel and invoke
  1066. code in physical address mode via KEXEC
  1067. config PHYSICAL_START
  1068. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1069. default "0x1000000" if X86_NUMAQ
  1070. default "0x200000" if X86_64
  1071. default "0x100000"
  1072. help
  1073. This gives the physical address where the kernel is loaded.
  1074. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1075. bzImage will decompress itself to above physical address and
  1076. run from there. Otherwise, bzImage will run from the address where
  1077. it has been loaded by the boot loader and will ignore above physical
  1078. address.
  1079. In normal kdump cases one does not have to set/change this option
  1080. as now bzImage can be compiled as a completely relocatable image
  1081. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1082. address. This option is mainly useful for the folks who don't want
  1083. to use a bzImage for capturing the crash dump and want to use a
  1084. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1085. to be specifically compiled to run from a specific memory area
  1086. (normally a reserved region) and this option comes handy.
  1087. So if you are using bzImage for capturing the crash dump, leave
  1088. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  1089. Otherwise if you plan to use vmlinux for capturing the crash dump
  1090. change this value to start of the reserved region (Typically 16MB
  1091. 0x1000000). In other words, it can be set based on the "X" value as
  1092. specified in the "crashkernel=YM@XM" command line boot parameter
  1093. passed to the panic-ed kernel. Typically this parameter is set as
  1094. crashkernel=64M@16M. Please take a look at
  1095. Documentation/kdump/kdump.txt for more details about crash dumps.
  1096. Usage of bzImage for capturing the crash dump is recommended as
  1097. one does not have to build two kernels. Same kernel can be used
  1098. as production kernel and capture kernel. Above option should have
  1099. gone away after relocatable bzImage support is introduced. But it
  1100. is present because there are users out there who continue to use
  1101. vmlinux for dump capture. This option should go away down the
  1102. line.
  1103. Don't change this unless you know what you are doing.
  1104. config RELOCATABLE
  1105. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1106. depends on EXPERIMENTAL
  1107. help
  1108. This builds a kernel image that retains relocation information
  1109. so it can be loaded someplace besides the default 1MB.
  1110. The relocations tend to make the kernel binary about 10% larger,
  1111. but are discarded at runtime.
  1112. One use is for the kexec on panic case where the recovery kernel
  1113. must live at a different physical address than the primary
  1114. kernel.
  1115. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1116. it has been loaded at and the compile time physical address
  1117. (CONFIG_PHYSICAL_START) is ignored.
  1118. config PHYSICAL_ALIGN
  1119. hex
  1120. prompt "Alignment value to which kernel should be aligned" if X86_32
  1121. default "0x100000" if X86_32
  1122. default "0x200000" if X86_64
  1123. range 0x2000 0x400000
  1124. help
  1125. This value puts the alignment restrictions on physical address
  1126. where kernel is loaded and run from. Kernel is compiled for an
  1127. address which meets above alignment restriction.
  1128. If bootloader loads the kernel at a non-aligned address and
  1129. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1130. address aligned to above value and run from there.
  1131. If bootloader loads the kernel at a non-aligned address and
  1132. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1133. load address and decompress itself to the address it has been
  1134. compiled for and run from there. The address for which kernel is
  1135. compiled already meets above alignment restrictions. Hence the
  1136. end result is that kernel runs from a physical address meeting
  1137. above alignment restrictions.
  1138. Don't change this unless you know what you are doing.
  1139. config HOTPLUG_CPU
  1140. bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
  1141. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  1142. ---help---
  1143. Say Y here to experiment with turning CPUs off and on, and to
  1144. enable suspend on SMP systems. CPUs can be controlled through
  1145. /sys/devices/system/cpu.
  1146. Say N if you want to disable CPU hotplug and don't need to
  1147. suspend.
  1148. config COMPAT_VDSO
  1149. def_bool y
  1150. prompt "Compat VDSO support"
  1151. depends on X86_32 || IA32_EMULATION
  1152. help
  1153. Map the 32-bit VDSO to the predictable old-style address too.
  1154. ---help---
  1155. Say N here if you are running a sufficiently recent glibc
  1156. version (2.3.3 or later), to remove the high-mapped
  1157. VDSO mapping and to exclusively use the randomized VDSO.
  1158. If unsure, say Y.
  1159. endmenu
  1160. config ARCH_ENABLE_MEMORY_HOTPLUG
  1161. def_bool y
  1162. depends on X86_64 || (X86_32 && HIGHMEM)
  1163. config HAVE_ARCH_EARLY_PFN_TO_NID
  1164. def_bool X86_64
  1165. depends on NUMA
  1166. menu "Power management options"
  1167. depends on !X86_VOYAGER
  1168. config ARCH_HIBERNATION_HEADER
  1169. def_bool y
  1170. depends on X86_64 && HIBERNATION
  1171. source "kernel/power/Kconfig"
  1172. source "drivers/acpi/Kconfig"
  1173. config X86_APM_BOOT
  1174. bool
  1175. default y
  1176. depends on APM || APM_MODULE
  1177. menuconfig APM
  1178. tristate "APM (Advanced Power Management) BIOS support"
  1179. depends on X86_32 && PM_SLEEP
  1180. ---help---
  1181. APM is a BIOS specification for saving power using several different
  1182. techniques. This is mostly useful for battery powered laptops with
  1183. APM compliant BIOSes. If you say Y here, the system time will be
  1184. reset after a RESUME operation, the /proc/apm device will provide
  1185. battery status information, and user-space programs will receive
  1186. notification of APM "events" (e.g. battery status change).
  1187. If you select "Y" here, you can disable actual use of the APM
  1188. BIOS by passing the "apm=off" option to the kernel at boot time.
  1189. Note that the APM support is almost completely disabled for
  1190. machines with more than one CPU.
  1191. In order to use APM, you will need supporting software. For location
  1192. and more information, read <file:Documentation/power/pm.txt> and the
  1193. Battery Powered Linux mini-HOWTO, available from
  1194. <http://www.tldp.org/docs.html#howto>.
  1195. This driver does not spin down disk drives (see the hdparm(8)
  1196. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1197. VESA-compliant "green" monitors.
  1198. This driver does not support the TI 4000M TravelMate and the ACER
  1199. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1200. desktop machines also don't have compliant BIOSes, and this driver
  1201. may cause those machines to panic during the boot phase.
  1202. Generally, if you don't have a battery in your machine, there isn't
  1203. much point in using this driver and you should say N. If you get
  1204. random kernel OOPSes or reboots that don't seem to be related to
  1205. anything, try disabling/enabling this option (or disabling/enabling
  1206. APM in your BIOS).
  1207. Some other things you should try when experiencing seemingly random,
  1208. "weird" problems:
  1209. 1) make sure that you have enough swap space and that it is
  1210. enabled.
  1211. 2) pass the "no-hlt" option to the kernel
  1212. 3) switch on floating point emulation in the kernel and pass
  1213. the "no387" option to the kernel
  1214. 4) pass the "floppy=nodma" option to the kernel
  1215. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1216. all but the first 4 MB of RAM)
  1217. 6) make sure that the CPU is not over clocked.
  1218. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1219. 8) disable the cache from your BIOS settings
  1220. 9) install a fan for the video card or exchange video RAM
  1221. 10) install a better fan for the CPU
  1222. 11) exchange RAM chips
  1223. 12) exchange the motherboard.
  1224. To compile this driver as a module, choose M here: the
  1225. module will be called apm.
  1226. if APM
  1227. config APM_IGNORE_USER_SUSPEND
  1228. bool "Ignore USER SUSPEND"
  1229. help
  1230. This option will ignore USER SUSPEND requests. On machines with a
  1231. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1232. series notebooks, it is necessary to say Y because of a BIOS bug.
  1233. config APM_DO_ENABLE
  1234. bool "Enable PM at boot time"
  1235. ---help---
  1236. Enable APM features at boot time. From page 36 of the APM BIOS
  1237. specification: "When disabled, the APM BIOS does not automatically
  1238. power manage devices, enter the Standby State, enter the Suspend
  1239. State, or take power saving steps in response to CPU Idle calls."
  1240. This driver will make CPU Idle calls when Linux is idle (unless this
  1241. feature is turned off -- see "Do CPU IDLE calls", below). This
  1242. should always save battery power, but more complicated APM features
  1243. will be dependent on your BIOS implementation. You may need to turn
  1244. this option off if your computer hangs at boot time when using APM
  1245. support, or if it beeps continuously instead of suspending. Turn
  1246. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1247. T400CDT. This is off by default since most machines do fine without
  1248. this feature.
  1249. config APM_CPU_IDLE
  1250. bool "Make CPU Idle calls when idle"
  1251. help
  1252. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1253. On some machines, this can activate improved power savings, such as
  1254. a slowed CPU clock rate, when the machine is idle. These idle calls
  1255. are made after the idle loop has run for some length of time (e.g.,
  1256. 333 mS). On some machines, this will cause a hang at boot time or
  1257. whenever the CPU becomes idle. (On machines with more than one CPU,
  1258. this option does nothing.)
  1259. config APM_DISPLAY_BLANK
  1260. bool "Enable console blanking using APM"
  1261. help
  1262. Enable console blanking using the APM. Some laptops can use this to
  1263. turn off the LCD backlight when the screen blanker of the Linux
  1264. virtual console blanks the screen. Note that this is only used by
  1265. the virtual console screen blanker, and won't turn off the backlight
  1266. when using the X Window system. This also doesn't have anything to
  1267. do with your VESA-compliant power-saving monitor. Further, this
  1268. option doesn't work for all laptops -- it might not turn off your
  1269. backlight at all, or it might print a lot of errors to the console,
  1270. especially if you are using gpm.
  1271. config APM_ALLOW_INTS
  1272. bool "Allow interrupts during APM BIOS calls"
  1273. help
  1274. Normally we disable external interrupts while we are making calls to
  1275. the APM BIOS as a measure to lessen the effects of a badly behaving
  1276. BIOS implementation. The BIOS should reenable interrupts if it
  1277. needs to. Unfortunately, some BIOSes do not -- especially those in
  1278. many of the newer IBM Thinkpads. If you experience hangs when you
  1279. suspend, try setting this to Y. Otherwise, say N.
  1280. config APM_REAL_MODE_POWER_OFF
  1281. bool "Use real mode APM BIOS call to power off"
  1282. help
  1283. Use real mode APM BIOS calls to switch off the computer. This is
  1284. a work-around for a number of buggy BIOSes. Switch this option on if
  1285. your computer crashes instead of powering off properly.
  1286. endif # APM
  1287. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1288. source "drivers/cpuidle/Kconfig"
  1289. endmenu
  1290. menu "Bus options (PCI etc.)"
  1291. config PCI
  1292. bool "PCI support"
  1293. default y
  1294. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1295. help
  1296. Find out whether you have a PCI motherboard. PCI is the name of a
  1297. bus system, i.e. the way the CPU talks to the other stuff inside
  1298. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1299. VESA. If you have PCI, say Y, otherwise N.
  1300. choice
  1301. prompt "PCI access mode"
  1302. depends on X86_32 && PCI
  1303. default PCI_GOANY
  1304. ---help---
  1305. On PCI systems, the BIOS can be used to detect the PCI devices and
  1306. determine their configuration. However, some old PCI motherboards
  1307. have BIOS bugs and may crash if this is done. Also, some embedded
  1308. PCI-based systems don't have any BIOS at all. Linux can also try to
  1309. detect the PCI hardware directly without using the BIOS.
  1310. With this option, you can specify how Linux should detect the
  1311. PCI devices. If you choose "BIOS", the BIOS will be used,
  1312. if you choose "Direct", the BIOS won't be used, and if you
  1313. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1314. If you choose "Any", the kernel will try MMCONFIG, then the
  1315. direct access method and falls back to the BIOS if that doesn't
  1316. work. If unsure, go with the default, which is "Any".
  1317. config PCI_GOBIOS
  1318. bool "BIOS"
  1319. config PCI_GOMMCONFIG
  1320. bool "MMConfig"
  1321. config PCI_GODIRECT
  1322. bool "Direct"
  1323. config PCI_GOOLPC
  1324. bool "OLPC"
  1325. depends on OLPC
  1326. config PCI_GOANY
  1327. bool "Any"
  1328. endchoice
  1329. config PCI_BIOS
  1330. def_bool y
  1331. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1332. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1333. config PCI_DIRECT
  1334. def_bool y
  1335. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1336. config PCI_MMCONFIG
  1337. def_bool y
  1338. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1339. config PCI_OLPC
  1340. def_bool y
  1341. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1342. config PCI_DOMAINS
  1343. def_bool y
  1344. depends on PCI
  1345. config PCI_MMCONFIG
  1346. bool "Support mmconfig PCI config space access"
  1347. depends on X86_64 && PCI && ACPI
  1348. config DMAR
  1349. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1350. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1351. help
  1352. DMA remapping (DMAR) devices support enables independent address
  1353. translations for Direct Memory Access (DMA) from devices.
  1354. These DMA remapping devices are reported via ACPI tables
  1355. and include PCI device scope covered by these DMA
  1356. remapping devices.
  1357. config DMAR_GFX_WA
  1358. def_bool y
  1359. prompt "Support for Graphics workaround"
  1360. depends on DMAR
  1361. help
  1362. Current Graphics drivers tend to use physical address
  1363. for DMA and avoid using DMA APIs. Setting this config
  1364. option permits the IOMMU driver to set a unity map for
  1365. all the OS-visible memory. Hence the driver can continue
  1366. to use physical addresses for DMA.
  1367. config DMAR_FLOPPY_WA
  1368. def_bool y
  1369. depends on DMAR
  1370. help
  1371. Floppy disk drivers are know to bypass DMA API calls
  1372. thereby failing to work when IOMMU is enabled. This
  1373. workaround will setup a 1:1 mapping for the first
  1374. 16M to make floppy (an ISA device) work.
  1375. source "drivers/pci/pcie/Kconfig"
  1376. source "drivers/pci/Kconfig"
  1377. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1378. config ISA_DMA_API
  1379. def_bool y
  1380. if X86_32
  1381. config ISA
  1382. bool "ISA support"
  1383. depends on !X86_VOYAGER
  1384. help
  1385. Find out whether you have ISA slots on your motherboard. ISA is the
  1386. name of a bus system, i.e. the way the CPU talks to the other stuff
  1387. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1388. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1389. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1390. config EISA
  1391. bool "EISA support"
  1392. depends on ISA
  1393. ---help---
  1394. The Extended Industry Standard Architecture (EISA) bus was
  1395. developed as an open alternative to the IBM MicroChannel bus.
  1396. The EISA bus provided some of the features of the IBM MicroChannel
  1397. bus while maintaining backward compatibility with cards made for
  1398. the older ISA bus. The EISA bus saw limited use between 1988 and
  1399. 1995 when it was made obsolete by the PCI bus.
  1400. Say Y here if you are building a kernel for an EISA-based machine.
  1401. Otherwise, say N.
  1402. source "drivers/eisa/Kconfig"
  1403. config MCA
  1404. bool "MCA support" if !X86_VOYAGER
  1405. default y if X86_VOYAGER
  1406. help
  1407. MicroChannel Architecture is found in some IBM PS/2 machines and
  1408. laptops. It is a bus system similar to PCI or ISA. See
  1409. <file:Documentation/mca.txt> (and especially the web page given
  1410. there) before attempting to build an MCA bus kernel.
  1411. source "drivers/mca/Kconfig"
  1412. config SCx200
  1413. tristate "NatSemi SCx200 support"
  1414. depends on !X86_VOYAGER
  1415. help
  1416. This provides basic support for National Semiconductor's
  1417. (now AMD's) Geode processors. The driver probes for the
  1418. PCI-IDs of several on-chip devices, so its a good dependency
  1419. for other scx200_* drivers.
  1420. If compiled as a module, the driver is named scx200.
  1421. config SCx200HR_TIMER
  1422. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1423. depends on SCx200 && GENERIC_TIME
  1424. default y
  1425. help
  1426. This driver provides a clocksource built upon the on-chip
  1427. 27MHz high-resolution timer. Its also a workaround for
  1428. NSC Geode SC-1100's buggy TSC, which loses time when the
  1429. processor goes idle (as is done by the scheduler). The
  1430. other workaround is idle=poll boot option.
  1431. config GEODE_MFGPT_TIMER
  1432. def_bool y
  1433. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1434. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1435. help
  1436. This driver provides a clock event source based on the MFGPT
  1437. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1438. MFGPTs have a better resolution and max interval than the
  1439. generic PIT, and are suitable for use as high-res timers.
  1440. config OLPC
  1441. bool "One Laptop Per Child support"
  1442. default n
  1443. help
  1444. Add support for detecting the unique features of the OLPC
  1445. XO hardware.
  1446. endif # X86_32
  1447. config K8_NB
  1448. def_bool y
  1449. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1450. source "drivers/pcmcia/Kconfig"
  1451. source "drivers/pci/hotplug/Kconfig"
  1452. endmenu
  1453. menu "Executable file formats / Emulations"
  1454. source "fs/Kconfig.binfmt"
  1455. config IA32_EMULATION
  1456. bool "IA32 Emulation"
  1457. depends on X86_64
  1458. select COMPAT_BINFMT_ELF
  1459. help
  1460. Include code to run 32-bit programs under a 64-bit kernel. You should
  1461. likely turn this on, unless you're 100% sure that you don't have any
  1462. 32-bit programs left.
  1463. config IA32_AOUT
  1464. tristate "IA32 a.out support"
  1465. depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
  1466. help
  1467. Support old a.out binaries in the 32bit emulation.
  1468. config COMPAT
  1469. def_bool y
  1470. depends on IA32_EMULATION
  1471. config COMPAT_FOR_U64_ALIGNMENT
  1472. def_bool COMPAT
  1473. depends on X86_64
  1474. config SYSVIPC_COMPAT
  1475. def_bool y
  1476. depends on X86_64 && COMPAT && SYSVIPC
  1477. endmenu
  1478. source "net/Kconfig"
  1479. source "drivers/Kconfig"
  1480. source "drivers/firmware/Kconfig"
  1481. source "fs/Kconfig"
  1482. source "arch/x86/Kconfig.debug"
  1483. source "security/Kconfig"
  1484. source "crypto/Kconfig"
  1485. source "arch/x86/kvm/Kconfig"
  1486. source "lib/Kconfig"