Kconfig 68 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_AOUT if X86_32
  18. select HAVE_READQ
  19. select HAVE_WRITEQ
  20. select HAVE_UNSTABLE_SCHED_CLOCK
  21. select HAVE_IDE
  22. select HAVE_OPROFILE
  23. select HAVE_PERF_EVENTS if (!M386 && !M486)
  24. select HAVE_IOREMAP_PROT
  25. select HAVE_KPROBES
  26. select ARCH_WANT_OPTIONAL_GPIOLIB
  27. select ARCH_WANT_FRAME_POINTERS
  28. select HAVE_DMA_ATTRS
  29. select HAVE_KRETPROBES
  30. select HAVE_OPTPROBES
  31. select HAVE_FTRACE_MCOUNT_RECORD
  32. select HAVE_DYNAMIC_FTRACE
  33. select HAVE_FUNCTION_TRACER
  34. select HAVE_FUNCTION_GRAPH_TRACER
  35. select HAVE_FUNCTION_GRAPH_FP_TEST
  36. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  37. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  38. select HAVE_SYSCALL_TRACEPOINTS
  39. select HAVE_KVM
  40. select HAVE_ARCH_KGDB
  41. select HAVE_ARCH_TRACEHOOK
  42. select HAVE_GENERIC_DMA_COHERENT if X86_32
  43. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  44. select USER_STACKTRACE_SUPPORT
  45. select HAVE_REGS_AND_STACK_ACCESS_API
  46. select HAVE_DMA_API_DEBUG
  47. select HAVE_KERNEL_GZIP
  48. select HAVE_KERNEL_BZIP2
  49. select HAVE_KERNEL_LZMA
  50. select HAVE_KERNEL_LZO
  51. select HAVE_HW_BREAKPOINT
  52. select HAVE_MIXED_BREAKPOINTS_REGS
  53. select PERF_EVENTS
  54. select ANON_INODES
  55. select HAVE_ARCH_KMEMCHECK
  56. select HAVE_USER_RETURN_NOTIFIER
  57. config INSTRUCTION_DECODER
  58. def_bool (KPROBES || PERF_EVENTS)
  59. config OUTPUT_FORMAT
  60. string
  61. default "elf32-i386" if X86_32
  62. default "elf64-x86-64" if X86_64
  63. config ARCH_DEFCONFIG
  64. string
  65. default "arch/x86/configs/i386_defconfig" if X86_32
  66. default "arch/x86/configs/x86_64_defconfig" if X86_64
  67. config GENERIC_TIME
  68. def_bool y
  69. config GENERIC_CMOS_UPDATE
  70. def_bool y
  71. config CLOCKSOURCE_WATCHDOG
  72. def_bool y
  73. config GENERIC_CLOCKEVENTS
  74. def_bool y
  75. config GENERIC_CLOCKEVENTS_BROADCAST
  76. def_bool y
  77. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  78. config LOCKDEP_SUPPORT
  79. def_bool y
  80. config STACKTRACE_SUPPORT
  81. def_bool y
  82. config HAVE_LATENCYTOP_SUPPORT
  83. def_bool y
  84. config MMU
  85. def_bool y
  86. config ZONE_DMA
  87. def_bool y
  88. config SBUS
  89. bool
  90. config NEED_DMA_MAP_STATE
  91. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  92. config NEED_SG_DMA_LENGTH
  93. def_bool y
  94. config GENERIC_ISA_DMA
  95. def_bool y
  96. config GENERIC_IOMAP
  97. def_bool y
  98. config GENERIC_BUG
  99. def_bool y
  100. depends on BUG
  101. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  102. config GENERIC_BUG_RELATIVE_POINTERS
  103. bool
  104. config GENERIC_HWEIGHT
  105. def_bool y
  106. config GENERIC_GPIO
  107. bool
  108. config ARCH_MAY_HAVE_PC_FDC
  109. def_bool y
  110. config RWSEM_GENERIC_SPINLOCK
  111. def_bool !X86_XADD
  112. config RWSEM_XCHGADD_ALGORITHM
  113. def_bool X86_XADD
  114. config ARCH_HAS_CPU_IDLE_WAIT
  115. def_bool y
  116. config GENERIC_CALIBRATE_DELAY
  117. def_bool y
  118. config GENERIC_TIME_VSYSCALL
  119. bool
  120. default X86_64
  121. config ARCH_HAS_CPU_RELAX
  122. def_bool y
  123. config ARCH_HAS_DEFAULT_IDLE
  124. def_bool y
  125. config ARCH_HAS_CACHE_LINE_SIZE
  126. def_bool y
  127. config HAVE_SETUP_PER_CPU_AREA
  128. def_bool y
  129. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  130. def_bool y
  131. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  132. def_bool y
  133. config HAVE_CPUMASK_OF_CPU_MAP
  134. def_bool X86_64_SMP
  135. config ARCH_HIBERNATION_POSSIBLE
  136. def_bool y
  137. config ARCH_SUSPEND_POSSIBLE
  138. def_bool y
  139. config ZONE_DMA32
  140. bool
  141. default X86_64
  142. config ARCH_POPULATES_NODE_MAP
  143. def_bool y
  144. config AUDIT_ARCH
  145. bool
  146. default X86_64
  147. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  148. def_bool y
  149. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  150. def_bool y
  151. config HAVE_EARLY_RES
  152. def_bool y
  153. config HAVE_INTEL_TXT
  154. def_bool y
  155. depends on EXPERIMENTAL && DMAR && ACPI
  156. # Use the generic interrupt handling code in kernel/irq/:
  157. config GENERIC_HARDIRQS
  158. def_bool y
  159. config GENERIC_HARDIRQS_NO__DO_IRQ
  160. def_bool y
  161. config GENERIC_IRQ_PROBE
  162. def_bool y
  163. config GENERIC_PENDING_IRQ
  164. def_bool y
  165. depends on GENERIC_HARDIRQS && SMP
  166. config USE_GENERIC_SMP_HELPERS
  167. def_bool y
  168. depends on SMP
  169. config X86_32_SMP
  170. def_bool y
  171. depends on X86_32 && SMP
  172. config X86_64_SMP
  173. def_bool y
  174. depends on X86_64 && SMP
  175. config X86_HT
  176. def_bool y
  177. depends on SMP
  178. config X86_TRAMPOLINE
  179. def_bool y
  180. depends on SMP || (64BIT && ACPI_SLEEP)
  181. config X86_32_LAZY_GS
  182. def_bool y
  183. depends on X86_32 && !CC_STACKPROTECTOR
  184. config ARCH_HWEIGHT_CFLAGS
  185. string
  186. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  187. default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
  188. config KTIME_SCALAR
  189. def_bool X86_32
  190. source "init/Kconfig"
  191. source "kernel/Kconfig.freezer"
  192. menu "Processor type and features"
  193. source "kernel/time/Kconfig"
  194. config SMP
  195. bool "Symmetric multi-processing support"
  196. ---help---
  197. This enables support for systems with more than one CPU. If you have
  198. a system with only one CPU, like most personal computers, say N. If
  199. you have a system with more than one CPU, say Y.
  200. If you say N here, the kernel will run on single and multiprocessor
  201. machines, but will use only one CPU of a multiprocessor machine. If
  202. you say Y here, the kernel will run on many, but not all,
  203. singleprocessor machines. On a singleprocessor machine, the kernel
  204. will run faster if you say N here.
  205. Note that if you say Y here and choose architecture "586" or
  206. "Pentium" under "Processor family", the kernel will not work on 486
  207. architectures. Similarly, multiprocessor kernels for the "PPro"
  208. architecture may not work on all Pentium based boards.
  209. People using multiprocessor machines who say Y here should also say
  210. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  211. Management" code will be disabled if you say Y here.
  212. See also <file:Documentation/i386/IO-APIC.txt>,
  213. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  214. <http://www.tldp.org/docs.html#howto>.
  215. If you don't know what to do here, say N.
  216. config X86_X2APIC
  217. bool "Support x2apic"
  218. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  219. ---help---
  220. This enables x2apic support on CPUs that have this feature.
  221. This allows 32-bit apic IDs (so it can support very large systems),
  222. and accesses the local apic via MSRs not via mmio.
  223. If you don't know what to do here, say N.
  224. config SPARSE_IRQ
  225. bool "Support sparse irq numbering"
  226. depends on PCI_MSI || HT_IRQ
  227. ---help---
  228. This enables support for sparse irqs. This is useful for distro
  229. kernels that want to define a high CONFIG_NR_CPUS value but still
  230. want to have low kernel memory footprint on smaller machines.
  231. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  232. out the irq_desc[] array in a more NUMA-friendly way. )
  233. If you don't know what to do here, say N.
  234. config NUMA_IRQ_DESC
  235. def_bool y
  236. depends on SPARSE_IRQ && NUMA
  237. config X86_MPPARSE
  238. bool "Enable MPS table" if ACPI
  239. default y
  240. depends on X86_LOCAL_APIC
  241. ---help---
  242. For old smp systems that do not have proper acpi support. Newer systems
  243. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  244. config X86_BIGSMP
  245. bool "Support for big SMP systems with more than 8 CPUs"
  246. depends on X86_32 && SMP
  247. ---help---
  248. This option is needed for the systems that have more than 8 CPUs
  249. if X86_32
  250. config X86_EXTENDED_PLATFORM
  251. bool "Support for extended (non-PC) x86 platforms"
  252. default y
  253. ---help---
  254. If you disable this option then the kernel will only support
  255. standard PC platforms. (which covers the vast majority of
  256. systems out there.)
  257. If you enable this option then you'll be able to select support
  258. for the following (non-PC) 32 bit x86 platforms:
  259. AMD Elan
  260. NUMAQ (IBM/Sequent)
  261. RDC R-321x SoC
  262. SGI 320/540 (Visual Workstation)
  263. Summit/EXA (IBM x440)
  264. Unisys ES7000 IA32 series
  265. Moorestown MID devices
  266. If you have one of these systems, or if you want to build a
  267. generic distribution kernel, say Y here - otherwise say N.
  268. endif
  269. if X86_64
  270. config X86_EXTENDED_PLATFORM
  271. bool "Support for extended (non-PC) x86 platforms"
  272. default y
  273. ---help---
  274. If you disable this option then the kernel will only support
  275. standard PC platforms. (which covers the vast majority of
  276. systems out there.)
  277. If you enable this option then you'll be able to select support
  278. for the following (non-PC) 64 bit x86 platforms:
  279. ScaleMP vSMP
  280. SGI Ultraviolet
  281. If you have one of these systems, or if you want to build a
  282. generic distribution kernel, say Y here - otherwise say N.
  283. endif
  284. # This is an alphabetically sorted list of 64 bit extended platforms
  285. # Please maintain the alphabetic order if and when there are additions
  286. config X86_VSMP
  287. bool "ScaleMP vSMP"
  288. select PARAVIRT
  289. depends on X86_64 && PCI
  290. depends on X86_EXTENDED_PLATFORM
  291. ---help---
  292. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  293. supposed to run on these EM64T-based machines. Only choose this option
  294. if you have one of these machines.
  295. config X86_UV
  296. bool "SGI Ultraviolet"
  297. depends on X86_64
  298. depends on X86_EXTENDED_PLATFORM
  299. depends on NUMA
  300. depends on X86_X2APIC
  301. ---help---
  302. This option is needed in order to support SGI Ultraviolet systems.
  303. If you don't have one of these, you should say N here.
  304. # Following is an alphabetically sorted list of 32 bit extended platforms
  305. # Please maintain the alphabetic order if and when there are additions
  306. config X86_ELAN
  307. bool "AMD Elan"
  308. depends on X86_32
  309. depends on X86_EXTENDED_PLATFORM
  310. ---help---
  311. Select this for an AMD Elan processor.
  312. Do not use this option for K6/Athlon/Opteron processors!
  313. If unsure, choose "PC-compatible" instead.
  314. config X86_MRST
  315. bool "Moorestown MID platform"
  316. depends on PCI
  317. depends on PCI_GOANY
  318. depends on X86_32
  319. depends on X86_EXTENDED_PLATFORM
  320. depends on X86_IO_APIC
  321. select APB_TIMER
  322. ---help---
  323. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  324. Internet Device(MID) platform. Moorestown consists of two chips:
  325. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  326. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  327. nor standard legacy replacement devices/features. e.g. Moorestown does
  328. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  329. config X86_RDC321X
  330. bool "RDC R-321x SoC"
  331. depends on X86_32
  332. depends on X86_EXTENDED_PLATFORM
  333. select M486
  334. select X86_REBOOTFIXUPS
  335. ---help---
  336. This option is needed for RDC R-321x system-on-chip, also known
  337. as R-8610-(G).
  338. If you don't have one of these chips, you should say N here.
  339. config X86_32_NON_STANDARD
  340. bool "Support non-standard 32-bit SMP architectures"
  341. depends on X86_32 && SMP
  342. depends on X86_EXTENDED_PLATFORM
  343. ---help---
  344. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  345. subarchitectures. It is intended for a generic binary kernel.
  346. if you select them all, kernel will probe it one by one. and will
  347. fallback to default.
  348. # Alphabetically sorted list of Non standard 32 bit platforms
  349. config X86_NUMAQ
  350. bool "NUMAQ (IBM/Sequent)"
  351. depends on X86_32_NON_STANDARD
  352. depends on PCI
  353. select NUMA
  354. select X86_MPPARSE
  355. ---help---
  356. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  357. NUMA multiquad box. This changes the way that processors are
  358. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  359. of Flat Logical. You will need a new lynxer.elf file to flash your
  360. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  361. config X86_SUPPORTS_MEMORY_FAILURE
  362. def_bool y
  363. # MCE code calls memory_failure():
  364. depends on X86_MCE
  365. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  366. depends on !X86_NUMAQ
  367. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  368. depends on X86_64 || !SPARSEMEM
  369. select ARCH_SUPPORTS_MEMORY_FAILURE
  370. config X86_VISWS
  371. bool "SGI 320/540 (Visual Workstation)"
  372. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  373. depends on X86_32_NON_STANDARD
  374. ---help---
  375. The SGI Visual Workstation series is an IA32-based workstation
  376. based on SGI systems chips with some legacy PC hardware attached.
  377. Say Y here to create a kernel to run on the SGI 320 or 540.
  378. A kernel compiled for the Visual Workstation will run on general
  379. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  380. config X86_SUMMIT
  381. bool "Summit/EXA (IBM x440)"
  382. depends on X86_32_NON_STANDARD
  383. ---help---
  384. This option is needed for IBM systems that use the Summit/EXA chipset.
  385. In particular, it is needed for the x440.
  386. config X86_ES7000
  387. bool "Unisys ES7000 IA32 series"
  388. depends on X86_32_NON_STANDARD && X86_BIGSMP
  389. ---help---
  390. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  391. supposed to run on an IA32-based Unisys ES7000 system.
  392. config SCHED_OMIT_FRAME_POINTER
  393. def_bool y
  394. prompt "Single-depth WCHAN output"
  395. depends on X86
  396. ---help---
  397. Calculate simpler /proc/<PID>/wchan values. If this option
  398. is disabled then wchan values will recurse back to the
  399. caller function. This provides more accurate wchan values,
  400. at the expense of slightly more scheduling overhead.
  401. If in doubt, say "Y".
  402. menuconfig PARAVIRT_GUEST
  403. bool "Paravirtualized guest support"
  404. ---help---
  405. Say Y here to get to see options related to running Linux under
  406. various hypervisors. This option alone does not add any kernel code.
  407. If you say N, all options in this submenu will be skipped and disabled.
  408. if PARAVIRT_GUEST
  409. source "arch/x86/xen/Kconfig"
  410. config VMI
  411. bool "VMI Guest support (DEPRECATED)"
  412. select PARAVIRT
  413. depends on X86_32
  414. ---help---
  415. VMI provides a paravirtualized interface to the VMware ESX server
  416. (it could be used by other hypervisors in theory too, but is not
  417. at the moment), by linking the kernel to a GPL-ed ROM module
  418. provided by the hypervisor.
  419. As of September 2009, VMware has started a phased retirement
  420. of this feature from VMware's products. Please see
  421. feature-removal-schedule.txt for details. If you are
  422. planning to enable this option, please note that you cannot
  423. live migrate a VMI enabled VM to a future VMware product,
  424. which doesn't support VMI. So if you expect your kernel to
  425. seamlessly migrate to newer VMware products, keep this
  426. disabled.
  427. config KVM_CLOCK
  428. bool "KVM paravirtualized clock"
  429. select PARAVIRT
  430. select PARAVIRT_CLOCK
  431. ---help---
  432. Turning on this option will allow you to run a paravirtualized clock
  433. when running over the KVM hypervisor. Instead of relying on a PIT
  434. (or probably other) emulation by the underlying device model, the host
  435. provides the guest with timing infrastructure such as time of day, and
  436. system time
  437. config KVM_GUEST
  438. bool "KVM Guest support"
  439. select PARAVIRT
  440. ---help---
  441. This option enables various optimizations for running under the KVM
  442. hypervisor.
  443. source "arch/x86/lguest/Kconfig"
  444. config PARAVIRT
  445. bool "Enable paravirtualization code"
  446. ---help---
  447. This changes the kernel so it can modify itself when it is run
  448. under a hypervisor, potentially improving performance significantly
  449. over full virtualization. However, when run without a hypervisor
  450. the kernel is theoretically slower and slightly larger.
  451. config PARAVIRT_SPINLOCKS
  452. bool "Paravirtualization layer for spinlocks"
  453. depends on PARAVIRT && SMP && EXPERIMENTAL
  454. ---help---
  455. Paravirtualized spinlocks allow a pvops backend to replace the
  456. spinlock implementation with something virtualization-friendly
  457. (for example, block the virtual CPU rather than spinning).
  458. Unfortunately the downside is an up to 5% performance hit on
  459. native kernels, with various workloads.
  460. If you are unsure how to answer this question, answer N.
  461. config PARAVIRT_CLOCK
  462. bool
  463. endif
  464. config PARAVIRT_DEBUG
  465. bool "paravirt-ops debugging"
  466. depends on PARAVIRT && DEBUG_KERNEL
  467. ---help---
  468. Enable to debug paravirt_ops internals. Specifically, BUG if
  469. a paravirt_op is missing when it is called.
  470. config NO_BOOTMEM
  471. default y
  472. bool "Disable Bootmem code"
  473. ---help---
  474. Use early_res directly instead of bootmem before slab is ready.
  475. - allocator (buddy) [generic]
  476. - early allocator (bootmem) [generic]
  477. - very early allocator (reserve_early*()) [x86]
  478. - very very early allocator (early brk model) [x86]
  479. So reduce one layer between early allocator to final allocator
  480. config MEMTEST
  481. bool "Memtest"
  482. ---help---
  483. This option adds a kernel parameter 'memtest', which allows memtest
  484. to be set.
  485. memtest=0, mean disabled; -- default
  486. memtest=1, mean do 1 test pattern;
  487. ...
  488. memtest=4, mean do 4 test patterns.
  489. If you are unsure how to answer this question, answer N.
  490. config X86_SUMMIT_NUMA
  491. def_bool y
  492. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  493. config X86_CYCLONE_TIMER
  494. def_bool y
  495. depends on X86_32_NON_STANDARD
  496. source "arch/x86/Kconfig.cpu"
  497. config HPET_TIMER
  498. def_bool X86_64
  499. prompt "HPET Timer Support" if X86_32
  500. ---help---
  501. Use the IA-PC HPET (High Precision Event Timer) to manage
  502. time in preference to the PIT and RTC, if a HPET is
  503. present.
  504. HPET is the next generation timer replacing legacy 8254s.
  505. The HPET provides a stable time base on SMP
  506. systems, unlike the TSC, but it is more expensive to access,
  507. as it is off-chip. You can find the HPET spec at
  508. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  509. You can safely choose Y here. However, HPET will only be
  510. activated if the platform and the BIOS support this feature.
  511. Otherwise the 8254 will be used for timing services.
  512. Choose N to continue using the legacy 8254 timer.
  513. config HPET_EMULATE_RTC
  514. def_bool y
  515. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  516. config APB_TIMER
  517. def_bool y if MRST
  518. prompt "Langwell APB Timer Support" if X86_MRST
  519. help
  520. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  521. The APBT provides a stable time base on SMP
  522. systems, unlike the TSC, but it is more expensive to access,
  523. as it is off-chip. APB timers are always running regardless of CPU
  524. C states, they are used as per CPU clockevent device when possible.
  525. # Mark as embedded because too many people got it wrong.
  526. # The code disables itself when not needed.
  527. config DMI
  528. default y
  529. bool "Enable DMI scanning" if EMBEDDED
  530. ---help---
  531. Enabled scanning of DMI to identify machine quirks. Say Y
  532. here unless you have verified that your setup is not
  533. affected by entries in the DMI blacklist. Required by PNP
  534. BIOS code.
  535. config GART_IOMMU
  536. bool "GART IOMMU support" if EMBEDDED
  537. default y
  538. select SWIOTLB
  539. depends on X86_64 && PCI && K8_NB
  540. ---help---
  541. Support for full DMA access of devices with 32bit memory access only
  542. on systems with more than 3GB. This is usually needed for USB,
  543. sound, many IDE/SATA chipsets and some other devices.
  544. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  545. based hardware IOMMU and a software bounce buffer based IOMMU used
  546. on Intel systems and as fallback.
  547. The code is only active when needed (enough memory and limited
  548. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  549. too.
  550. config CALGARY_IOMMU
  551. bool "IBM Calgary IOMMU support"
  552. select SWIOTLB
  553. depends on X86_64 && PCI && EXPERIMENTAL
  554. ---help---
  555. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  556. systems. Needed to run systems with more than 3GB of memory
  557. properly with 32-bit PCI devices that do not support DAC
  558. (Double Address Cycle). Calgary also supports bus level
  559. isolation, where all DMAs pass through the IOMMU. This
  560. prevents them from going anywhere except their intended
  561. destination. This catches hard-to-find kernel bugs and
  562. mis-behaving drivers and devices that do not use the DMA-API
  563. properly to set up their DMA buffers. The IOMMU can be
  564. turned off at boot time with the iommu=off parameter.
  565. Normally the kernel will make the right choice by itself.
  566. If unsure, say Y.
  567. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  568. def_bool y
  569. prompt "Should Calgary be enabled by default?"
  570. depends on CALGARY_IOMMU
  571. ---help---
  572. Should Calgary be enabled by default? if you choose 'y', Calgary
  573. will be used (if it exists). If you choose 'n', Calgary will not be
  574. used even if it exists. If you choose 'n' and would like to use
  575. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  576. If unsure, say Y.
  577. config AMD_IOMMU
  578. bool "AMD IOMMU support"
  579. select SWIOTLB
  580. select PCI_MSI
  581. depends on X86_64 && PCI && ACPI
  582. ---help---
  583. With this option you can enable support for AMD IOMMU hardware in
  584. your system. An IOMMU is a hardware component which provides
  585. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  586. can isolate the the DMA memory of different devices and protect the
  587. system from misbehaving device drivers or hardware.
  588. You can find out if your system has an AMD IOMMU if you look into
  589. your BIOS for an option to enable it or if you have an IVRS ACPI
  590. table.
  591. config AMD_IOMMU_STATS
  592. bool "Export AMD IOMMU statistics to debugfs"
  593. depends on AMD_IOMMU
  594. select DEBUG_FS
  595. ---help---
  596. This option enables code in the AMD IOMMU driver to collect various
  597. statistics about whats happening in the driver and exports that
  598. information to userspace via debugfs.
  599. If unsure, say N.
  600. # need this always selected by IOMMU for the VIA workaround
  601. config SWIOTLB
  602. def_bool y if X86_64
  603. ---help---
  604. Support for software bounce buffers used on x86-64 systems
  605. which don't have a hardware IOMMU (e.g. the current generation
  606. of Intel's x86-64 CPUs). Using this PCI devices which can only
  607. access 32-bits of memory can be used on systems with more than
  608. 3 GB of memory. If unsure, say Y.
  609. config IOMMU_HELPER
  610. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  611. config IOMMU_API
  612. def_bool (AMD_IOMMU || DMAR)
  613. config MAXSMP
  614. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  615. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  616. select CPUMASK_OFFSTACK
  617. ---help---
  618. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  619. If unsure, say N.
  620. config NR_CPUS
  621. int "Maximum number of CPUs" if SMP && !MAXSMP
  622. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  623. range 2 512 if SMP && !MAXSMP
  624. default "1" if !SMP
  625. default "4096" if MAXSMP
  626. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  627. default "8" if SMP
  628. ---help---
  629. This allows you to specify the maximum number of CPUs which this
  630. kernel will support. The maximum supported value is 512 and the
  631. minimum value which makes sense is 2.
  632. This is purely to save memory - each supported CPU adds
  633. approximately eight kilobytes to the kernel image.
  634. config SCHED_SMT
  635. bool "SMT (Hyperthreading) scheduler support"
  636. depends on X86_HT
  637. ---help---
  638. SMT scheduler support improves the CPU scheduler's decision making
  639. when dealing with Intel Pentium 4 chips with HyperThreading at a
  640. cost of slightly increased overhead in some places. If unsure say
  641. N here.
  642. config SCHED_MC
  643. def_bool y
  644. prompt "Multi-core scheduler support"
  645. depends on X86_HT
  646. ---help---
  647. Multi-core scheduler support improves the CPU scheduler's decision
  648. making when dealing with multi-core CPU chips at a cost of slightly
  649. increased overhead in some places. If unsure say N here.
  650. source "kernel/Kconfig.preempt"
  651. config X86_UP_APIC
  652. bool "Local APIC support on uniprocessors"
  653. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  654. ---help---
  655. A local APIC (Advanced Programmable Interrupt Controller) is an
  656. integrated interrupt controller in the CPU. If you have a single-CPU
  657. system which has a processor with a local APIC, you can say Y here to
  658. enable and use it. If you say Y here even though your machine doesn't
  659. have a local APIC, then the kernel will still run with no slowdown at
  660. all. The local APIC supports CPU-generated self-interrupts (timer,
  661. performance counters), and the NMI watchdog which detects hard
  662. lockups.
  663. config X86_UP_IOAPIC
  664. bool "IO-APIC support on uniprocessors"
  665. depends on X86_UP_APIC
  666. ---help---
  667. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  668. SMP-capable replacement for PC-style interrupt controllers. Most
  669. SMP systems and many recent uniprocessor systems have one.
  670. If you have a single-CPU system with an IO-APIC, you can say Y here
  671. to use it. If you say Y here even though your machine doesn't have
  672. an IO-APIC, then the kernel will still run with no slowdown at all.
  673. config X86_LOCAL_APIC
  674. def_bool y
  675. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  676. config X86_IO_APIC
  677. def_bool y
  678. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  679. config X86_VISWS_APIC
  680. def_bool y
  681. depends on X86_32 && X86_VISWS
  682. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  683. bool "Reroute for broken boot IRQs"
  684. depends on X86_IO_APIC
  685. ---help---
  686. This option enables a workaround that fixes a source of
  687. spurious interrupts. This is recommended when threaded
  688. interrupt handling is used on systems where the generation of
  689. superfluous "boot interrupts" cannot be disabled.
  690. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  691. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  692. kernel does during interrupt handling). On chipsets where this
  693. boot IRQ generation cannot be disabled, this workaround keeps
  694. the original IRQ line masked so that only the equivalent "boot
  695. IRQ" is delivered to the CPUs. The workaround also tells the
  696. kernel to set up the IRQ handler on the boot IRQ line. In this
  697. way only one interrupt is delivered to the kernel. Otherwise
  698. the spurious second interrupt may cause the kernel to bring
  699. down (vital) interrupt lines.
  700. Only affects "broken" chipsets. Interrupt sharing may be
  701. increased on these systems.
  702. config X86_MCE
  703. bool "Machine Check / overheating reporting"
  704. ---help---
  705. Machine Check support allows the processor to notify the
  706. kernel if it detects a problem (e.g. overheating, data corruption).
  707. The action the kernel takes depends on the severity of the problem,
  708. ranging from warning messages to halting the machine.
  709. config X86_MCE_INTEL
  710. def_bool y
  711. prompt "Intel MCE features"
  712. depends on X86_MCE && X86_LOCAL_APIC
  713. ---help---
  714. Additional support for intel specific MCE features such as
  715. the thermal monitor.
  716. config X86_MCE_AMD
  717. def_bool y
  718. prompt "AMD MCE features"
  719. depends on X86_MCE && X86_LOCAL_APIC
  720. ---help---
  721. Additional support for AMD specific MCE features such as
  722. the DRAM Error Threshold.
  723. config X86_ANCIENT_MCE
  724. bool "Support for old Pentium 5 / WinChip machine checks"
  725. depends on X86_32 && X86_MCE
  726. ---help---
  727. Include support for machine check handling on old Pentium 5 or WinChip
  728. systems. These typically need to be enabled explicitely on the command
  729. line.
  730. config X86_MCE_THRESHOLD
  731. depends on X86_MCE_AMD || X86_MCE_INTEL
  732. def_bool y
  733. config X86_MCE_INJECT
  734. depends on X86_MCE
  735. tristate "Machine check injector support"
  736. ---help---
  737. Provide support for injecting machine checks for testing purposes.
  738. If you don't know what a machine check is and you don't do kernel
  739. QA it is safe to say n.
  740. config X86_THERMAL_VECTOR
  741. def_bool y
  742. depends on X86_MCE_INTEL
  743. config VM86
  744. bool "Enable VM86 support" if EMBEDDED
  745. default y
  746. depends on X86_32
  747. ---help---
  748. This option is required by programs like DOSEMU to run 16-bit legacy
  749. code on X86 processors. It also may be needed by software like
  750. XFree86 to initialize some video cards via BIOS. Disabling this
  751. option saves about 6k.
  752. config TOSHIBA
  753. tristate "Toshiba Laptop support"
  754. depends on X86_32
  755. ---help---
  756. This adds a driver to safely access the System Management Mode of
  757. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  758. not work on models with a Phoenix BIOS. The System Management Mode
  759. is used to set the BIOS and power saving options on Toshiba portables.
  760. For information on utilities to make use of this driver see the
  761. Toshiba Linux utilities web site at:
  762. <http://www.buzzard.org.uk/toshiba/>.
  763. Say Y if you intend to run this kernel on a Toshiba portable.
  764. Say N otherwise.
  765. config I8K
  766. tristate "Dell laptop support"
  767. ---help---
  768. This adds a driver to safely access the System Management Mode
  769. of the CPU on the Dell Inspiron 8000. The System Management Mode
  770. is used to read cpu temperature and cooling fan status and to
  771. control the fans on the I8K portables.
  772. This driver has been tested only on the Inspiron 8000 but it may
  773. also work with other Dell laptops. You can force loading on other
  774. models by passing the parameter `force=1' to the module. Use at
  775. your own risk.
  776. For information on utilities to make use of this driver see the
  777. I8K Linux utilities web site at:
  778. <http://people.debian.org/~dz/i8k/>
  779. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  780. Say N otherwise.
  781. config X86_REBOOTFIXUPS
  782. bool "Enable X86 board specific fixups for reboot"
  783. depends on X86_32
  784. ---help---
  785. This enables chipset and/or board specific fixups to be done
  786. in order to get reboot to work correctly. This is only needed on
  787. some combinations of hardware and BIOS. The symptom, for which
  788. this config is intended, is when reboot ends with a stalled/hung
  789. system.
  790. Currently, the only fixup is for the Geode machines using
  791. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  792. Say Y if you want to enable the fixup. Currently, it's safe to
  793. enable this option even if you don't need it.
  794. Say N otherwise.
  795. config MICROCODE
  796. tristate "/dev/cpu/microcode - microcode support"
  797. select FW_LOADER
  798. ---help---
  799. If you say Y here, you will be able to update the microcode on
  800. certain Intel and AMD processors. The Intel support is for the
  801. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  802. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  803. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  804. You will obviously need the actual microcode binary data itself
  805. which is not shipped with the Linux kernel.
  806. This option selects the general module only, you need to select
  807. at least one vendor specific module as well.
  808. To compile this driver as a module, choose M here: the
  809. module will be called microcode.
  810. config MICROCODE_INTEL
  811. bool "Intel microcode patch loading support"
  812. depends on MICROCODE
  813. default MICROCODE
  814. select FW_LOADER
  815. ---help---
  816. This options enables microcode patch loading support for Intel
  817. processors.
  818. For latest news and information on obtaining all the required
  819. Intel ingredients for this driver, check:
  820. <http://www.urbanmyth.org/microcode/>.
  821. config MICROCODE_AMD
  822. bool "AMD microcode patch loading support"
  823. depends on MICROCODE
  824. select FW_LOADER
  825. ---help---
  826. If you select this option, microcode patch loading support for AMD
  827. processors will be enabled.
  828. config MICROCODE_OLD_INTERFACE
  829. def_bool y
  830. depends on MICROCODE
  831. config X86_MSR
  832. tristate "/dev/cpu/*/msr - Model-specific register support"
  833. ---help---
  834. This device gives privileged processes access to the x86
  835. Model-Specific Registers (MSRs). It is a character device with
  836. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  837. MSR accesses are directed to a specific CPU on multi-processor
  838. systems.
  839. config X86_CPUID
  840. tristate "/dev/cpu/*/cpuid - CPU information support"
  841. ---help---
  842. This device gives processes access to the x86 CPUID instruction to
  843. be executed on a specific processor. It is a character device
  844. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  845. /dev/cpu/31/cpuid.
  846. choice
  847. prompt "High Memory Support"
  848. default HIGHMEM64G if X86_NUMAQ
  849. default HIGHMEM4G
  850. depends on X86_32
  851. config NOHIGHMEM
  852. bool "off"
  853. depends on !X86_NUMAQ
  854. ---help---
  855. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  856. However, the address space of 32-bit x86 processors is only 4
  857. Gigabytes large. That means that, if you have a large amount of
  858. physical memory, not all of it can be "permanently mapped" by the
  859. kernel. The physical memory that's not permanently mapped is called
  860. "high memory".
  861. If you are compiling a kernel which will never run on a machine with
  862. more than 1 Gigabyte total physical RAM, answer "off" here (default
  863. choice and suitable for most users). This will result in a "3GB/1GB"
  864. split: 3GB are mapped so that each process sees a 3GB virtual memory
  865. space and the remaining part of the 4GB virtual memory space is used
  866. by the kernel to permanently map as much physical memory as
  867. possible.
  868. If the machine has between 1 and 4 Gigabytes physical RAM, then
  869. answer "4GB" here.
  870. If more than 4 Gigabytes is used then answer "64GB" here. This
  871. selection turns Intel PAE (Physical Address Extension) mode on.
  872. PAE implements 3-level paging on IA32 processors. PAE is fully
  873. supported by Linux, PAE mode is implemented on all recent Intel
  874. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  875. then the kernel will not boot on CPUs that don't support PAE!
  876. The actual amount of total physical memory will either be
  877. auto detected or can be forced by using a kernel command line option
  878. such as "mem=256M". (Try "man bootparam" or see the documentation of
  879. your boot loader (lilo or loadlin) about how to pass options to the
  880. kernel at boot time.)
  881. If unsure, say "off".
  882. config HIGHMEM4G
  883. bool "4GB"
  884. depends on !X86_NUMAQ
  885. ---help---
  886. Select this if you have a 32-bit processor and between 1 and 4
  887. gigabytes of physical RAM.
  888. config HIGHMEM64G
  889. bool "64GB"
  890. depends on !M386 && !M486
  891. select X86_PAE
  892. ---help---
  893. Select this if you have a 32-bit processor and more than 4
  894. gigabytes of physical RAM.
  895. endchoice
  896. choice
  897. depends on EXPERIMENTAL
  898. prompt "Memory split" if EMBEDDED
  899. default VMSPLIT_3G
  900. depends on X86_32
  901. ---help---
  902. Select the desired split between kernel and user memory.
  903. If the address range available to the kernel is less than the
  904. physical memory installed, the remaining memory will be available
  905. as "high memory". Accessing high memory is a little more costly
  906. than low memory, as it needs to be mapped into the kernel first.
  907. Note that increasing the kernel address space limits the range
  908. available to user programs, making the address space there
  909. tighter. Selecting anything other than the default 3G/1G split
  910. will also likely make your kernel incompatible with binary-only
  911. kernel modules.
  912. If you are not absolutely sure what you are doing, leave this
  913. option alone!
  914. config VMSPLIT_3G
  915. bool "3G/1G user/kernel split"
  916. config VMSPLIT_3G_OPT
  917. depends on !X86_PAE
  918. bool "3G/1G user/kernel split (for full 1G low memory)"
  919. config VMSPLIT_2G
  920. bool "2G/2G user/kernel split"
  921. config VMSPLIT_2G_OPT
  922. depends on !X86_PAE
  923. bool "2G/2G user/kernel split (for full 2G low memory)"
  924. config VMSPLIT_1G
  925. bool "1G/3G user/kernel split"
  926. endchoice
  927. config PAGE_OFFSET
  928. hex
  929. default 0xB0000000 if VMSPLIT_3G_OPT
  930. default 0x80000000 if VMSPLIT_2G
  931. default 0x78000000 if VMSPLIT_2G_OPT
  932. default 0x40000000 if VMSPLIT_1G
  933. default 0xC0000000
  934. depends on X86_32
  935. config HIGHMEM
  936. def_bool y
  937. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  938. config X86_PAE
  939. bool "PAE (Physical Address Extension) Support"
  940. depends on X86_32 && !HIGHMEM4G
  941. ---help---
  942. PAE is required for NX support, and furthermore enables
  943. larger swapspace support for non-overcommit purposes. It
  944. has the cost of more pagetable lookup overhead, and also
  945. consumes more pagetable space per process.
  946. config ARCH_PHYS_ADDR_T_64BIT
  947. def_bool X86_64 || X86_PAE
  948. config DIRECT_GBPAGES
  949. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  950. default y
  951. depends on X86_64
  952. ---help---
  953. Allow the kernel linear mapping to use 1GB pages on CPUs that
  954. support it. This can improve the kernel's performance a tiny bit by
  955. reducing TLB pressure. If in doubt, say "Y".
  956. # Common NUMA Features
  957. config NUMA
  958. bool "Numa Memory Allocation and Scheduler Support"
  959. depends on SMP
  960. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  961. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  962. ---help---
  963. Enable NUMA (Non Uniform Memory Access) support.
  964. The kernel will try to allocate memory used by a CPU on the
  965. local memory controller of the CPU and add some more
  966. NUMA awareness to the kernel.
  967. For 64-bit this is recommended if the system is Intel Core i7
  968. (or later), AMD Opteron, or EM64T NUMA.
  969. For 32-bit this is only needed on (rare) 32-bit-only platforms
  970. that support NUMA topologies, such as NUMAQ / Summit, or if you
  971. boot a 32-bit kernel on a 64-bit NUMA platform.
  972. Otherwise, you should say N.
  973. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  974. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  975. config K8_NUMA
  976. def_bool y
  977. prompt "Old style AMD Opteron NUMA detection"
  978. depends on X86_64 && NUMA && PCI
  979. ---help---
  980. Enable K8 NUMA node topology detection. You should say Y here if
  981. you have a multi processor AMD K8 system. This uses an old
  982. method to read the NUMA configuration directly from the builtin
  983. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  984. instead, which also takes priority if both are compiled in.
  985. config X86_64_ACPI_NUMA
  986. def_bool y
  987. prompt "ACPI NUMA detection"
  988. depends on X86_64 && NUMA && ACPI && PCI
  989. select ACPI_NUMA
  990. ---help---
  991. Enable ACPI SRAT based node topology detection.
  992. # Some NUMA nodes have memory ranges that span
  993. # other nodes. Even though a pfn is valid and
  994. # between a node's start and end pfns, it may not
  995. # reside on that node. See memmap_init_zone()
  996. # for details.
  997. config NODES_SPAN_OTHER_NODES
  998. def_bool y
  999. depends on X86_64_ACPI_NUMA
  1000. config NUMA_EMU
  1001. bool "NUMA emulation"
  1002. depends on X86_64 && NUMA
  1003. ---help---
  1004. Enable NUMA emulation. A flat machine will be split
  1005. into virtual nodes when booted with "numa=fake=N", where N is the
  1006. number of nodes. This is only useful for debugging.
  1007. config NODES_SHIFT
  1008. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1009. range 1 10
  1010. default "10" if MAXSMP
  1011. default "6" if X86_64
  1012. default "4" if X86_NUMAQ
  1013. default "3"
  1014. depends on NEED_MULTIPLE_NODES
  1015. ---help---
  1016. Specify the maximum number of NUMA Nodes available on the target
  1017. system. Increases memory reserved to accommodate various tables.
  1018. config HAVE_ARCH_BOOTMEM
  1019. def_bool y
  1020. depends on X86_32 && NUMA
  1021. config ARCH_HAVE_MEMORY_PRESENT
  1022. def_bool y
  1023. depends on X86_32 && DISCONTIGMEM
  1024. config NEED_NODE_MEMMAP_SIZE
  1025. def_bool y
  1026. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1027. config HAVE_ARCH_ALLOC_REMAP
  1028. def_bool y
  1029. depends on X86_32 && NUMA
  1030. config ARCH_FLATMEM_ENABLE
  1031. def_bool y
  1032. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1033. config ARCH_DISCONTIGMEM_ENABLE
  1034. def_bool y
  1035. depends on NUMA && X86_32
  1036. config ARCH_DISCONTIGMEM_DEFAULT
  1037. def_bool y
  1038. depends on NUMA && X86_32
  1039. config ARCH_PROC_KCORE_TEXT
  1040. def_bool y
  1041. depends on X86_64 && PROC_KCORE
  1042. config ARCH_SPARSEMEM_DEFAULT
  1043. def_bool y
  1044. depends on X86_64
  1045. config ARCH_SPARSEMEM_ENABLE
  1046. def_bool y
  1047. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1048. select SPARSEMEM_STATIC if X86_32
  1049. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1050. config ARCH_SELECT_MEMORY_MODEL
  1051. def_bool y
  1052. depends on ARCH_SPARSEMEM_ENABLE
  1053. config ARCH_MEMORY_PROBE
  1054. def_bool X86_64
  1055. depends on MEMORY_HOTPLUG
  1056. config ILLEGAL_POINTER_VALUE
  1057. hex
  1058. default 0 if X86_32
  1059. default 0xdead000000000000 if X86_64
  1060. source "mm/Kconfig"
  1061. config HIGHPTE
  1062. bool "Allocate 3rd-level pagetables from highmem"
  1063. depends on HIGHMEM
  1064. ---help---
  1065. The VM uses one page table entry for each page of physical memory.
  1066. For systems with a lot of RAM, this can be wasteful of precious
  1067. low memory. Setting this option will put user-space page table
  1068. entries in high memory.
  1069. config X86_CHECK_BIOS_CORRUPTION
  1070. bool "Check for low memory corruption"
  1071. ---help---
  1072. Periodically check for memory corruption in low memory, which
  1073. is suspected to be caused by BIOS. Even when enabled in the
  1074. configuration, it is disabled at runtime. Enable it by
  1075. setting "memory_corruption_check=1" on the kernel command
  1076. line. By default it scans the low 64k of memory every 60
  1077. seconds; see the memory_corruption_check_size and
  1078. memory_corruption_check_period parameters in
  1079. Documentation/kernel-parameters.txt to adjust this.
  1080. When enabled with the default parameters, this option has
  1081. almost no overhead, as it reserves a relatively small amount
  1082. of memory and scans it infrequently. It both detects corruption
  1083. and prevents it from affecting the running system.
  1084. It is, however, intended as a diagnostic tool; if repeatable
  1085. BIOS-originated corruption always affects the same memory,
  1086. you can use memmap= to prevent the kernel from using that
  1087. memory.
  1088. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1089. bool "Set the default setting of memory_corruption_check"
  1090. depends on X86_CHECK_BIOS_CORRUPTION
  1091. default y
  1092. ---help---
  1093. Set whether the default state of memory_corruption_check is
  1094. on or off.
  1095. config X86_RESERVE_LOW_64K
  1096. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1097. default y
  1098. ---help---
  1099. Reserve the first 64K of physical RAM on BIOSes that are known
  1100. to potentially corrupt that memory range. A numbers of BIOSes are
  1101. known to utilize this area during suspend/resume, so it must not
  1102. be used by the kernel.
  1103. Set this to N if you are absolutely sure that you trust the BIOS
  1104. to get all its memory reservations and usages right.
  1105. If you have doubts about the BIOS (e.g. suspend/resume does not
  1106. work or there's kernel crashes after certain hardware hotplug
  1107. events) and it's not AMI or Phoenix, then you might want to enable
  1108. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1109. corruption patterns.
  1110. Say Y if unsure.
  1111. config MATH_EMULATION
  1112. bool
  1113. prompt "Math emulation" if X86_32
  1114. ---help---
  1115. Linux can emulate a math coprocessor (used for floating point
  1116. operations) if you don't have one. 486DX and Pentium processors have
  1117. a math coprocessor built in, 486SX and 386 do not, unless you added
  1118. a 487DX or 387, respectively. (The messages during boot time can
  1119. give you some hints here ["man dmesg"].) Everyone needs either a
  1120. coprocessor or this emulation.
  1121. If you don't have a math coprocessor, you need to say Y here; if you
  1122. say Y here even though you have a coprocessor, the coprocessor will
  1123. be used nevertheless. (This behavior can be changed with the kernel
  1124. command line option "no387", which comes handy if your coprocessor
  1125. is broken. Try "man bootparam" or see the documentation of your boot
  1126. loader (lilo or loadlin) about how to pass options to the kernel at
  1127. boot time.) This means that it is a good idea to say Y here if you
  1128. intend to use this kernel on different machines.
  1129. More information about the internals of the Linux math coprocessor
  1130. emulation can be found in <file:arch/x86/math-emu/README>.
  1131. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1132. kernel, it won't hurt.
  1133. config MTRR
  1134. def_bool y
  1135. prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
  1136. ---help---
  1137. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1138. the Memory Type Range Registers (MTRRs) may be used to control
  1139. processor access to memory ranges. This is most useful if you have
  1140. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1141. allows bus write transfers to be combined into a larger transfer
  1142. before bursting over the PCI/AGP bus. This can increase performance
  1143. of image write operations 2.5 times or more. Saying Y here creates a
  1144. /proc/mtrr file which may be used to manipulate your processor's
  1145. MTRRs. Typically the X server should use this.
  1146. This code has a reasonably generic interface so that similar
  1147. control registers on other processors can be easily supported
  1148. as well:
  1149. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1150. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1151. these, the ARRs are used to emulate the MTRRs.
  1152. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1153. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1154. write-combining. All of these processors are supported by this code
  1155. and it makes sense to say Y here if you have one of them.
  1156. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1157. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1158. can lead to all sorts of problems, so it's good to say Y here.
  1159. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1160. just add about 9 KB to your kernel.
  1161. See <file:Documentation/x86/mtrr.txt> for more information.
  1162. config MTRR_SANITIZER
  1163. def_bool y
  1164. prompt "MTRR cleanup support"
  1165. depends on MTRR
  1166. ---help---
  1167. Convert MTRR layout from continuous to discrete, so X drivers can
  1168. add writeback entries.
  1169. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1170. The largest mtrr entry size for a continuous block can be set with
  1171. mtrr_chunk_size.
  1172. If unsure, say Y.
  1173. config MTRR_SANITIZER_ENABLE_DEFAULT
  1174. int "MTRR cleanup enable value (0-1)"
  1175. range 0 1
  1176. default "0"
  1177. depends on MTRR_SANITIZER
  1178. ---help---
  1179. Enable mtrr cleanup default value
  1180. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1181. int "MTRR cleanup spare reg num (0-7)"
  1182. range 0 7
  1183. default "1"
  1184. depends on MTRR_SANITIZER
  1185. ---help---
  1186. mtrr cleanup spare entries default, it can be changed via
  1187. mtrr_spare_reg_nr=N on the kernel command line.
  1188. config X86_PAT
  1189. def_bool y
  1190. prompt "x86 PAT support" if EMBEDDED
  1191. depends on MTRR
  1192. ---help---
  1193. Use PAT attributes to setup page level cache control.
  1194. PATs are the modern equivalents of MTRRs and are much more
  1195. flexible than MTRRs.
  1196. Say N here if you see bootup problems (boot crash, boot hang,
  1197. spontaneous reboots) or a non-working video driver.
  1198. If unsure, say Y.
  1199. config ARCH_USES_PG_UNCACHED
  1200. def_bool y
  1201. depends on X86_PAT
  1202. config EFI
  1203. bool "EFI runtime service support"
  1204. depends on ACPI
  1205. ---help---
  1206. This enables the kernel to use EFI runtime services that are
  1207. available (such as the EFI variable services).
  1208. This option is only useful on systems that have EFI firmware.
  1209. In addition, you should use the latest ELILO loader available
  1210. at <http://elilo.sourceforge.net> in order to take advantage
  1211. of EFI runtime services. However, even with this option, the
  1212. resultant kernel should continue to boot on existing non-EFI
  1213. platforms.
  1214. config SECCOMP
  1215. def_bool y
  1216. prompt "Enable seccomp to safely compute untrusted bytecode"
  1217. ---help---
  1218. This kernel feature is useful for number crunching applications
  1219. that may need to compute untrusted bytecode during their
  1220. execution. By using pipes or other transports made available to
  1221. the process as file descriptors supporting the read/write
  1222. syscalls, it's possible to isolate those applications in
  1223. their own address space using seccomp. Once seccomp is
  1224. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1225. and the task is only allowed to execute a few safe syscalls
  1226. defined by each seccomp mode.
  1227. If unsure, say Y. Only embedded should say N here.
  1228. config CC_STACKPROTECTOR
  1229. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1230. ---help---
  1231. This option turns on the -fstack-protector GCC feature. This
  1232. feature puts, at the beginning of functions, a canary value on
  1233. the stack just before the return address, and validates
  1234. the value just before actually returning. Stack based buffer
  1235. overflows (that need to overwrite this return address) now also
  1236. overwrite the canary, which gets detected and the attack is then
  1237. neutralized via a kernel panic.
  1238. This feature requires gcc version 4.2 or above, or a distribution
  1239. gcc with the feature backported. Older versions are automatically
  1240. detected and for those versions, this configuration option is
  1241. ignored. (and a warning is printed during bootup)
  1242. source kernel/Kconfig.hz
  1243. config KEXEC
  1244. bool "kexec system call"
  1245. ---help---
  1246. kexec is a system call that implements the ability to shutdown your
  1247. current kernel, and to start another kernel. It is like a reboot
  1248. but it is independent of the system firmware. And like a reboot
  1249. you can start any kernel with it, not just Linux.
  1250. The name comes from the similarity to the exec system call.
  1251. It is an ongoing process to be certain the hardware in a machine
  1252. is properly shutdown, so do not be surprised if this code does not
  1253. initially work for you. It may help to enable device hotplugging
  1254. support. As of this writing the exact hardware interface is
  1255. strongly in flux, so no good recommendation can be made.
  1256. config CRASH_DUMP
  1257. bool "kernel crash dumps"
  1258. depends on X86_64 || (X86_32 && HIGHMEM)
  1259. ---help---
  1260. Generate crash dump after being started by kexec.
  1261. This should be normally only set in special crash dump kernels
  1262. which are loaded in the main kernel with kexec-tools into
  1263. a specially reserved region and then later executed after
  1264. a crash by kdump/kexec. The crash dump kernel must be compiled
  1265. to a memory address not used by the main kernel or BIOS using
  1266. PHYSICAL_START, or it must be built as a relocatable image
  1267. (CONFIG_RELOCATABLE=y).
  1268. For more details see Documentation/kdump/kdump.txt
  1269. config KEXEC_JUMP
  1270. bool "kexec jump (EXPERIMENTAL)"
  1271. depends on EXPERIMENTAL
  1272. depends on KEXEC && HIBERNATION
  1273. ---help---
  1274. Jump between original kernel and kexeced kernel and invoke
  1275. code in physical address mode via KEXEC
  1276. config PHYSICAL_START
  1277. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1278. default "0x1000000"
  1279. ---help---
  1280. This gives the physical address where the kernel is loaded.
  1281. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1282. bzImage will decompress itself to above physical address and
  1283. run from there. Otherwise, bzImage will run from the address where
  1284. it has been loaded by the boot loader and will ignore above physical
  1285. address.
  1286. In normal kdump cases one does not have to set/change this option
  1287. as now bzImage can be compiled as a completely relocatable image
  1288. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1289. address. This option is mainly useful for the folks who don't want
  1290. to use a bzImage for capturing the crash dump and want to use a
  1291. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1292. to be specifically compiled to run from a specific memory area
  1293. (normally a reserved region) and this option comes handy.
  1294. So if you are using bzImage for capturing the crash dump,
  1295. leave the value here unchanged to 0x1000000 and set
  1296. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1297. for capturing the crash dump change this value to start of
  1298. the reserved region. In other words, it can be set based on
  1299. the "X" value as specified in the "crashkernel=YM@XM"
  1300. command line boot parameter passed to the panic-ed
  1301. kernel. Please take a look at Documentation/kdump/kdump.txt
  1302. for more details about crash dumps.
  1303. Usage of bzImage for capturing the crash dump is recommended as
  1304. one does not have to build two kernels. Same kernel can be used
  1305. as production kernel and capture kernel. Above option should have
  1306. gone away after relocatable bzImage support is introduced. But it
  1307. is present because there are users out there who continue to use
  1308. vmlinux for dump capture. This option should go away down the
  1309. line.
  1310. Don't change this unless you know what you are doing.
  1311. config RELOCATABLE
  1312. bool "Build a relocatable kernel"
  1313. default y
  1314. ---help---
  1315. This builds a kernel image that retains relocation information
  1316. so it can be loaded someplace besides the default 1MB.
  1317. The relocations tend to make the kernel binary about 10% larger,
  1318. but are discarded at runtime.
  1319. One use is for the kexec on panic case where the recovery kernel
  1320. must live at a different physical address than the primary
  1321. kernel.
  1322. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1323. it has been loaded at and the compile time physical address
  1324. (CONFIG_PHYSICAL_START) is ignored.
  1325. # Relocation on x86-32 needs some additional build support
  1326. config X86_NEED_RELOCS
  1327. def_bool y
  1328. depends on X86_32 && RELOCATABLE
  1329. config PHYSICAL_ALIGN
  1330. hex "Alignment value to which kernel should be aligned" if X86_32
  1331. default "0x1000000"
  1332. range 0x2000 0x1000000
  1333. ---help---
  1334. This value puts the alignment restrictions on physical address
  1335. where kernel is loaded and run from. Kernel is compiled for an
  1336. address which meets above alignment restriction.
  1337. If bootloader loads the kernel at a non-aligned address and
  1338. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1339. address aligned to above value and run from there.
  1340. If bootloader loads the kernel at a non-aligned address and
  1341. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1342. load address and decompress itself to the address it has been
  1343. compiled for and run from there. The address for which kernel is
  1344. compiled already meets above alignment restrictions. Hence the
  1345. end result is that kernel runs from a physical address meeting
  1346. above alignment restrictions.
  1347. Don't change this unless you know what you are doing.
  1348. config HOTPLUG_CPU
  1349. bool "Support for hot-pluggable CPUs"
  1350. depends on SMP && HOTPLUG
  1351. ---help---
  1352. Say Y here to allow turning CPUs off and on. CPUs can be
  1353. controlled through /sys/devices/system/cpu.
  1354. ( Note: power management support will enable this option
  1355. automatically on SMP systems. )
  1356. Say N if you want to disable CPU hotplug.
  1357. config COMPAT_VDSO
  1358. def_bool y
  1359. prompt "Compat VDSO support"
  1360. depends on X86_32 || IA32_EMULATION
  1361. ---help---
  1362. Map the 32-bit VDSO to the predictable old-style address too.
  1363. Say N here if you are running a sufficiently recent glibc
  1364. version (2.3.3 or later), to remove the high-mapped
  1365. VDSO mapping and to exclusively use the randomized VDSO.
  1366. If unsure, say Y.
  1367. config CMDLINE_BOOL
  1368. bool "Built-in kernel command line"
  1369. ---help---
  1370. Allow for specifying boot arguments to the kernel at
  1371. build time. On some systems (e.g. embedded ones), it is
  1372. necessary or convenient to provide some or all of the
  1373. kernel boot arguments with the kernel itself (that is,
  1374. to not rely on the boot loader to provide them.)
  1375. To compile command line arguments into the kernel,
  1376. set this option to 'Y', then fill in the
  1377. the boot arguments in CONFIG_CMDLINE.
  1378. Systems with fully functional boot loaders (i.e. non-embedded)
  1379. should leave this option set to 'N'.
  1380. config CMDLINE
  1381. string "Built-in kernel command string"
  1382. depends on CMDLINE_BOOL
  1383. default ""
  1384. ---help---
  1385. Enter arguments here that should be compiled into the kernel
  1386. image and used at boot time. If the boot loader provides a
  1387. command line at boot time, it is appended to this string to
  1388. form the full kernel command line, when the system boots.
  1389. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1390. change this behavior.
  1391. In most cases, the command line (whether built-in or provided
  1392. by the boot loader) should specify the device for the root
  1393. file system.
  1394. config CMDLINE_OVERRIDE
  1395. bool "Built-in command line overrides boot loader arguments"
  1396. depends on CMDLINE_BOOL
  1397. ---help---
  1398. Set this option to 'Y' to have the kernel ignore the boot loader
  1399. command line, and use ONLY the built-in command line.
  1400. This is used to work around broken boot loaders. This should
  1401. be set to 'N' under normal conditions.
  1402. endmenu
  1403. config ARCH_ENABLE_MEMORY_HOTPLUG
  1404. def_bool y
  1405. depends on X86_64 || (X86_32 && HIGHMEM)
  1406. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1407. def_bool y
  1408. depends on MEMORY_HOTPLUG
  1409. config HAVE_ARCH_EARLY_PFN_TO_NID
  1410. def_bool X86_64
  1411. depends on NUMA
  1412. config USE_PERCPU_NUMA_NODE_ID
  1413. def_bool X86_64
  1414. depends on NUMA
  1415. menu "Power management and ACPI options"
  1416. config ARCH_HIBERNATION_HEADER
  1417. def_bool y
  1418. depends on X86_64 && HIBERNATION
  1419. source "kernel/power/Kconfig"
  1420. source "drivers/acpi/Kconfig"
  1421. source "drivers/sfi/Kconfig"
  1422. config X86_APM_BOOT
  1423. def_bool y
  1424. depends on APM || APM_MODULE
  1425. menuconfig APM
  1426. tristate "APM (Advanced Power Management) BIOS support"
  1427. depends on X86_32 && PM_SLEEP
  1428. ---help---
  1429. APM is a BIOS specification for saving power using several different
  1430. techniques. This is mostly useful for battery powered laptops with
  1431. APM compliant BIOSes. If you say Y here, the system time will be
  1432. reset after a RESUME operation, the /proc/apm device will provide
  1433. battery status information, and user-space programs will receive
  1434. notification of APM "events" (e.g. battery status change).
  1435. If you select "Y" here, you can disable actual use of the APM
  1436. BIOS by passing the "apm=off" option to the kernel at boot time.
  1437. Note that the APM support is almost completely disabled for
  1438. machines with more than one CPU.
  1439. In order to use APM, you will need supporting software. For location
  1440. and more information, read <file:Documentation/power/pm.txt> and the
  1441. Battery Powered Linux mini-HOWTO, available from
  1442. <http://www.tldp.org/docs.html#howto>.
  1443. This driver does not spin down disk drives (see the hdparm(8)
  1444. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1445. VESA-compliant "green" monitors.
  1446. This driver does not support the TI 4000M TravelMate and the ACER
  1447. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1448. desktop machines also don't have compliant BIOSes, and this driver
  1449. may cause those machines to panic during the boot phase.
  1450. Generally, if you don't have a battery in your machine, there isn't
  1451. much point in using this driver and you should say N. If you get
  1452. random kernel OOPSes or reboots that don't seem to be related to
  1453. anything, try disabling/enabling this option (or disabling/enabling
  1454. APM in your BIOS).
  1455. Some other things you should try when experiencing seemingly random,
  1456. "weird" problems:
  1457. 1) make sure that you have enough swap space and that it is
  1458. enabled.
  1459. 2) pass the "no-hlt" option to the kernel
  1460. 3) switch on floating point emulation in the kernel and pass
  1461. the "no387" option to the kernel
  1462. 4) pass the "floppy=nodma" option to the kernel
  1463. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1464. all but the first 4 MB of RAM)
  1465. 6) make sure that the CPU is not over clocked.
  1466. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1467. 8) disable the cache from your BIOS settings
  1468. 9) install a fan for the video card or exchange video RAM
  1469. 10) install a better fan for the CPU
  1470. 11) exchange RAM chips
  1471. 12) exchange the motherboard.
  1472. To compile this driver as a module, choose M here: the
  1473. module will be called apm.
  1474. if APM
  1475. config APM_IGNORE_USER_SUSPEND
  1476. bool "Ignore USER SUSPEND"
  1477. ---help---
  1478. This option will ignore USER SUSPEND requests. On machines with a
  1479. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1480. series notebooks, it is necessary to say Y because of a BIOS bug.
  1481. config APM_DO_ENABLE
  1482. bool "Enable PM at boot time"
  1483. ---help---
  1484. Enable APM features at boot time. From page 36 of the APM BIOS
  1485. specification: "When disabled, the APM BIOS does not automatically
  1486. power manage devices, enter the Standby State, enter the Suspend
  1487. State, or take power saving steps in response to CPU Idle calls."
  1488. This driver will make CPU Idle calls when Linux is idle (unless this
  1489. feature is turned off -- see "Do CPU IDLE calls", below). This
  1490. should always save battery power, but more complicated APM features
  1491. will be dependent on your BIOS implementation. You may need to turn
  1492. this option off if your computer hangs at boot time when using APM
  1493. support, or if it beeps continuously instead of suspending. Turn
  1494. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1495. T400CDT. This is off by default since most machines do fine without
  1496. this feature.
  1497. config APM_CPU_IDLE
  1498. bool "Make CPU Idle calls when idle"
  1499. ---help---
  1500. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1501. On some machines, this can activate improved power savings, such as
  1502. a slowed CPU clock rate, when the machine is idle. These idle calls
  1503. are made after the idle loop has run for some length of time (e.g.,
  1504. 333 mS). On some machines, this will cause a hang at boot time or
  1505. whenever the CPU becomes idle. (On machines with more than one CPU,
  1506. this option does nothing.)
  1507. config APM_DISPLAY_BLANK
  1508. bool "Enable console blanking using APM"
  1509. ---help---
  1510. Enable console blanking using the APM. Some laptops can use this to
  1511. turn off the LCD backlight when the screen blanker of the Linux
  1512. virtual console blanks the screen. Note that this is only used by
  1513. the virtual console screen blanker, and won't turn off the backlight
  1514. when using the X Window system. This also doesn't have anything to
  1515. do with your VESA-compliant power-saving monitor. Further, this
  1516. option doesn't work for all laptops -- it might not turn off your
  1517. backlight at all, or it might print a lot of errors to the console,
  1518. especially if you are using gpm.
  1519. config APM_ALLOW_INTS
  1520. bool "Allow interrupts during APM BIOS calls"
  1521. ---help---
  1522. Normally we disable external interrupts while we are making calls to
  1523. the APM BIOS as a measure to lessen the effects of a badly behaving
  1524. BIOS implementation. The BIOS should reenable interrupts if it
  1525. needs to. Unfortunately, some BIOSes do not -- especially those in
  1526. many of the newer IBM Thinkpads. If you experience hangs when you
  1527. suspend, try setting this to Y. Otherwise, say N.
  1528. endif # APM
  1529. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1530. source "drivers/cpuidle/Kconfig"
  1531. source "drivers/idle/Kconfig"
  1532. endmenu
  1533. menu "Bus options (PCI etc.)"
  1534. config PCI
  1535. bool "PCI support"
  1536. default y
  1537. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1538. ---help---
  1539. Find out whether you have a PCI motherboard. PCI is the name of a
  1540. bus system, i.e. the way the CPU talks to the other stuff inside
  1541. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1542. VESA. If you have PCI, say Y, otherwise N.
  1543. choice
  1544. prompt "PCI access mode"
  1545. depends on X86_32 && PCI
  1546. default PCI_GOANY
  1547. ---help---
  1548. On PCI systems, the BIOS can be used to detect the PCI devices and
  1549. determine their configuration. However, some old PCI motherboards
  1550. have BIOS bugs and may crash if this is done. Also, some embedded
  1551. PCI-based systems don't have any BIOS at all. Linux can also try to
  1552. detect the PCI hardware directly without using the BIOS.
  1553. With this option, you can specify how Linux should detect the
  1554. PCI devices. If you choose "BIOS", the BIOS will be used,
  1555. if you choose "Direct", the BIOS won't be used, and if you
  1556. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1557. If you choose "Any", the kernel will try MMCONFIG, then the
  1558. direct access method and falls back to the BIOS if that doesn't
  1559. work. If unsure, go with the default, which is "Any".
  1560. config PCI_GOBIOS
  1561. bool "BIOS"
  1562. config PCI_GOMMCONFIG
  1563. bool "MMConfig"
  1564. config PCI_GODIRECT
  1565. bool "Direct"
  1566. config PCI_GOOLPC
  1567. bool "OLPC"
  1568. depends on OLPC
  1569. config PCI_GOANY
  1570. bool "Any"
  1571. endchoice
  1572. config PCI_BIOS
  1573. def_bool y
  1574. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1575. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1576. config PCI_DIRECT
  1577. def_bool y
  1578. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1579. config PCI_MMCONFIG
  1580. def_bool y
  1581. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1582. config PCI_OLPC
  1583. def_bool y
  1584. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1585. config PCI_DOMAINS
  1586. def_bool y
  1587. depends on PCI
  1588. config PCI_MMCONFIG
  1589. bool "Support mmconfig PCI config space access"
  1590. depends on X86_64 && PCI && ACPI
  1591. config PCI_CNB20LE_QUIRK
  1592. bool "Read CNB20LE Host Bridge Windows"
  1593. depends on PCI
  1594. help
  1595. Read the PCI windows out of the CNB20LE host bridge. This allows
  1596. PCI hotplug to work on systems with the CNB20LE chipset which do
  1597. not have ACPI.
  1598. config DMAR
  1599. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1600. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1601. help
  1602. DMA remapping (DMAR) devices support enables independent address
  1603. translations for Direct Memory Access (DMA) from devices.
  1604. These DMA remapping devices are reported via ACPI tables
  1605. and include PCI device scope covered by these DMA
  1606. remapping devices.
  1607. config DMAR_DEFAULT_ON
  1608. def_bool y
  1609. prompt "Enable DMA Remapping Devices by default"
  1610. depends on DMAR
  1611. help
  1612. Selecting this option will enable a DMAR device at boot time if
  1613. one is found. If this option is not selected, DMAR support can
  1614. be enabled by passing intel_iommu=on to the kernel. It is
  1615. recommended you say N here while the DMAR code remains
  1616. experimental.
  1617. config DMAR_BROKEN_GFX_WA
  1618. bool "Workaround broken graphics drivers (going away soon)"
  1619. depends on DMAR && BROKEN
  1620. ---help---
  1621. Current Graphics drivers tend to use physical address
  1622. for DMA and avoid using DMA APIs. Setting this config
  1623. option permits the IOMMU driver to set a unity map for
  1624. all the OS-visible memory. Hence the driver can continue
  1625. to use physical addresses for DMA, at least until this
  1626. option is removed in the 2.6.32 kernel.
  1627. config DMAR_FLOPPY_WA
  1628. def_bool y
  1629. depends on DMAR
  1630. ---help---
  1631. Floppy disk drivers are known to bypass DMA API calls
  1632. thereby failing to work when IOMMU is enabled. This
  1633. workaround will setup a 1:1 mapping for the first
  1634. 16MiB to make floppy (an ISA device) work.
  1635. config INTR_REMAP
  1636. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1637. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1638. ---help---
  1639. Supports Interrupt remapping for IO-APIC and MSI devices.
  1640. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1641. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1642. source "drivers/pci/pcie/Kconfig"
  1643. source "drivers/pci/Kconfig"
  1644. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1645. config ISA_DMA_API
  1646. def_bool y
  1647. if X86_32
  1648. config ISA
  1649. bool "ISA support"
  1650. ---help---
  1651. Find out whether you have ISA slots on your motherboard. ISA is the
  1652. name of a bus system, i.e. the way the CPU talks to the other stuff
  1653. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1654. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1655. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1656. config EISA
  1657. bool "EISA support"
  1658. depends on ISA
  1659. ---help---
  1660. The Extended Industry Standard Architecture (EISA) bus was
  1661. developed as an open alternative to the IBM MicroChannel bus.
  1662. The EISA bus provided some of the features of the IBM MicroChannel
  1663. bus while maintaining backward compatibility with cards made for
  1664. the older ISA bus. The EISA bus saw limited use between 1988 and
  1665. 1995 when it was made obsolete by the PCI bus.
  1666. Say Y here if you are building a kernel for an EISA-based machine.
  1667. Otherwise, say N.
  1668. source "drivers/eisa/Kconfig"
  1669. config MCA
  1670. bool "MCA support"
  1671. ---help---
  1672. MicroChannel Architecture is found in some IBM PS/2 machines and
  1673. laptops. It is a bus system similar to PCI or ISA. See
  1674. <file:Documentation/mca.txt> (and especially the web page given
  1675. there) before attempting to build an MCA bus kernel.
  1676. source "drivers/mca/Kconfig"
  1677. config SCx200
  1678. tristate "NatSemi SCx200 support"
  1679. ---help---
  1680. This provides basic support for National Semiconductor's
  1681. (now AMD's) Geode processors. The driver probes for the
  1682. PCI-IDs of several on-chip devices, so its a good dependency
  1683. for other scx200_* drivers.
  1684. If compiled as a module, the driver is named scx200.
  1685. config SCx200HR_TIMER
  1686. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1687. depends on SCx200 && GENERIC_TIME
  1688. default y
  1689. ---help---
  1690. This driver provides a clocksource built upon the on-chip
  1691. 27MHz high-resolution timer. Its also a workaround for
  1692. NSC Geode SC-1100's buggy TSC, which loses time when the
  1693. processor goes idle (as is done by the scheduler). The
  1694. other workaround is idle=poll boot option.
  1695. config OLPC
  1696. bool "One Laptop Per Child support"
  1697. select GPIOLIB
  1698. ---help---
  1699. Add support for detecting the unique features of the OLPC
  1700. XO hardware.
  1701. endif # X86_32
  1702. config K8_NB
  1703. def_bool y
  1704. depends on CPU_SUP_AMD && PCI
  1705. source "drivers/pcmcia/Kconfig"
  1706. source "drivers/pci/hotplug/Kconfig"
  1707. endmenu
  1708. menu "Executable file formats / Emulations"
  1709. source "fs/Kconfig.binfmt"
  1710. config IA32_EMULATION
  1711. bool "IA32 Emulation"
  1712. depends on X86_64
  1713. select COMPAT_BINFMT_ELF
  1714. ---help---
  1715. Include code to run 32-bit programs under a 64-bit kernel. You should
  1716. likely turn this on, unless you're 100% sure that you don't have any
  1717. 32-bit programs left.
  1718. config IA32_AOUT
  1719. tristate "IA32 a.out support"
  1720. depends on IA32_EMULATION
  1721. ---help---
  1722. Support old a.out binaries in the 32bit emulation.
  1723. config COMPAT
  1724. def_bool y
  1725. depends on IA32_EMULATION
  1726. config COMPAT_FOR_U64_ALIGNMENT
  1727. def_bool COMPAT
  1728. depends on X86_64
  1729. config SYSVIPC_COMPAT
  1730. def_bool y
  1731. depends on COMPAT && SYSVIPC
  1732. endmenu
  1733. config HAVE_ATOMIC_IOMAP
  1734. def_bool y
  1735. depends on X86_32
  1736. source "net/Kconfig"
  1737. source "drivers/Kconfig"
  1738. source "drivers/firmware/Kconfig"
  1739. source "fs/Kconfig"
  1740. source "arch/x86/Kconfig.debug"
  1741. source "security/Kconfig"
  1742. source "crypto/Kconfig"
  1743. source "arch/x86/kvm/Kconfig"
  1744. source "lib/Kconfig"