Kconfig 67 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_IOREMAP_PROT
  24. select HAVE_KPROBES
  25. select ARCH_WANT_OPTIONAL_GPIOLIB
  26. select ARCH_WANT_FRAME_POINTERS
  27. select HAVE_KRETPROBES
  28. select HAVE_FTRACE_MCOUNT_RECORD
  29. select HAVE_DYNAMIC_FTRACE
  30. select HAVE_FUNCTION_TRACER
  31. select HAVE_FUNCTION_GRAPH_TRACER
  32. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  33. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  34. select HAVE_FTRACE_SYSCALLS
  35. select HAVE_KVM
  36. select HAVE_ARCH_KGDB
  37. select HAVE_ARCH_TRACEHOOK
  38. select HAVE_GENERIC_DMA_COHERENT if X86_32
  39. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  40. select USER_STACKTRACE_SUPPORT
  41. select HAVE_DMA_API_DEBUG
  42. select HAVE_KERNEL_GZIP
  43. select HAVE_KERNEL_BZIP2
  44. select HAVE_KERNEL_LZMA
  45. config OUTPUT_FORMAT
  46. string
  47. default "elf32-i386" if X86_32
  48. default "elf64-x86-64" if X86_64
  49. config ARCH_DEFCONFIG
  50. string
  51. default "arch/x86/configs/i386_defconfig" if X86_32
  52. default "arch/x86/configs/x86_64_defconfig" if X86_64
  53. config GENERIC_TIME
  54. def_bool y
  55. config GENERIC_CMOS_UPDATE
  56. def_bool y
  57. config CLOCKSOURCE_WATCHDOG
  58. def_bool y
  59. config GENERIC_CLOCKEVENTS
  60. def_bool y
  61. config GENERIC_CLOCKEVENTS_BROADCAST
  62. def_bool y
  63. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  64. config LOCKDEP_SUPPORT
  65. def_bool y
  66. config STACKTRACE_SUPPORT
  67. def_bool y
  68. config HAVE_LATENCYTOP_SUPPORT
  69. def_bool y
  70. config FAST_CMPXCHG_LOCAL
  71. bool
  72. default y
  73. config MMU
  74. def_bool y
  75. config ZONE_DMA
  76. def_bool y
  77. config SBUS
  78. bool
  79. config GENERIC_ISA_DMA
  80. def_bool y
  81. config GENERIC_IOMAP
  82. def_bool y
  83. config GENERIC_BUG
  84. def_bool y
  85. depends on BUG
  86. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  87. config GENERIC_BUG_RELATIVE_POINTERS
  88. bool
  89. config GENERIC_HWEIGHT
  90. def_bool y
  91. config GENERIC_GPIO
  92. bool
  93. config ARCH_MAY_HAVE_PC_FDC
  94. def_bool y
  95. config RWSEM_GENERIC_SPINLOCK
  96. def_bool !X86_XADD
  97. config RWSEM_XCHGADD_ALGORITHM
  98. def_bool X86_XADD
  99. config ARCH_HAS_CPU_IDLE_WAIT
  100. def_bool y
  101. config GENERIC_CALIBRATE_DELAY
  102. def_bool y
  103. config GENERIC_TIME_VSYSCALL
  104. bool
  105. default X86_64
  106. config ARCH_HAS_CPU_RELAX
  107. def_bool y
  108. config ARCH_HAS_DEFAULT_IDLE
  109. def_bool y
  110. config ARCH_HAS_CACHE_LINE_SIZE
  111. def_bool y
  112. config HAVE_SETUP_PER_CPU_AREA
  113. def_bool y
  114. config HAVE_DYNAMIC_PER_CPU_AREA
  115. def_bool y
  116. config HAVE_CPUMASK_OF_CPU_MAP
  117. def_bool X86_64_SMP
  118. config ARCH_HIBERNATION_POSSIBLE
  119. def_bool y
  120. config ARCH_SUSPEND_POSSIBLE
  121. def_bool y
  122. config ZONE_DMA32
  123. bool
  124. default X86_64
  125. config ARCH_POPULATES_NODE_MAP
  126. def_bool y
  127. config AUDIT_ARCH
  128. bool
  129. default X86_64
  130. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  131. def_bool y
  132. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  133. def_bool y
  134. # Use the generic interrupt handling code in kernel/irq/:
  135. config GENERIC_HARDIRQS
  136. bool
  137. default y
  138. config GENERIC_HARDIRQS_NO__DO_IRQ
  139. def_bool y
  140. config GENERIC_IRQ_PROBE
  141. bool
  142. default y
  143. config GENERIC_PENDING_IRQ
  144. bool
  145. depends on GENERIC_HARDIRQS && SMP
  146. default y
  147. config USE_GENERIC_SMP_HELPERS
  148. def_bool y
  149. depends on SMP
  150. config X86_32_SMP
  151. def_bool y
  152. depends on X86_32 && SMP
  153. config X86_64_SMP
  154. def_bool y
  155. depends on X86_64 && SMP
  156. config X86_HT
  157. bool
  158. depends on SMP
  159. default y
  160. config X86_TRAMPOLINE
  161. bool
  162. depends on SMP || (64BIT && ACPI_SLEEP)
  163. default y
  164. config X86_32_LAZY_GS
  165. def_bool y
  166. depends on X86_32 && !CC_STACKPROTECTOR
  167. config KTIME_SCALAR
  168. def_bool X86_32
  169. source "init/Kconfig"
  170. source "kernel/Kconfig.freezer"
  171. menu "Processor type and features"
  172. source "kernel/time/Kconfig"
  173. config SMP
  174. bool "Symmetric multi-processing support"
  175. ---help---
  176. This enables support for systems with more than one CPU. If you have
  177. a system with only one CPU, like most personal computers, say N. If
  178. you have a system with more than one CPU, say Y.
  179. If you say N here, the kernel will run on single and multiprocessor
  180. machines, but will use only one CPU of a multiprocessor machine. If
  181. you say Y here, the kernel will run on many, but not all,
  182. singleprocessor machines. On a singleprocessor machine, the kernel
  183. will run faster if you say N here.
  184. Note that if you say Y here and choose architecture "586" or
  185. "Pentium" under "Processor family", the kernel will not work on 486
  186. architectures. Similarly, multiprocessor kernels for the "PPro"
  187. architecture may not work on all Pentium based boards.
  188. People using multiprocessor machines who say Y here should also say
  189. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  190. Management" code will be disabled if you say Y here.
  191. See also <file:Documentation/i386/IO-APIC.txt>,
  192. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  193. <http://www.tldp.org/docs.html#howto>.
  194. If you don't know what to do here, say N.
  195. config X86_X2APIC
  196. bool "Support x2apic"
  197. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  198. ---help---
  199. This enables x2apic support on CPUs that have this feature.
  200. This allows 32-bit apic IDs (so it can support very large systems),
  201. and accesses the local apic via MSRs not via mmio.
  202. If you don't know what to do here, say N.
  203. config SPARSE_IRQ
  204. bool "Support sparse irq numbering"
  205. depends on PCI_MSI || HT_IRQ
  206. ---help---
  207. This enables support for sparse irqs. This is useful for distro
  208. kernels that want to define a high CONFIG_NR_CPUS value but still
  209. want to have low kernel memory footprint on smaller machines.
  210. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  211. out the irq_desc[] array in a more NUMA-friendly way. )
  212. If you don't know what to do here, say N.
  213. config NUMA_IRQ_DESC
  214. def_bool y
  215. depends on SPARSE_IRQ && NUMA
  216. config X86_MPPARSE
  217. bool "Enable MPS table" if ACPI
  218. default y
  219. depends on X86_LOCAL_APIC
  220. ---help---
  221. For old smp systems that do not have proper acpi support. Newer systems
  222. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  223. config X86_BIGSMP
  224. bool "Support for big SMP systems with more than 8 CPUs"
  225. depends on X86_32 && SMP
  226. ---help---
  227. This option is needed for the systems that have more than 8 CPUs
  228. if X86_32
  229. config X86_EXTENDED_PLATFORM
  230. bool "Support for extended (non-PC) x86 platforms"
  231. default y
  232. ---help---
  233. If you disable this option then the kernel will only support
  234. standard PC platforms. (which covers the vast majority of
  235. systems out there.)
  236. If you enable this option then you'll be able to select support
  237. for the following (non-PC) 32 bit x86 platforms:
  238. AMD Elan
  239. NUMAQ (IBM/Sequent)
  240. RDC R-321x SoC
  241. SGI 320/540 (Visual Workstation)
  242. Summit/EXA (IBM x440)
  243. Unisys ES7000 IA32 series
  244. If you have one of these systems, or if you want to build a
  245. generic distribution kernel, say Y here - otherwise say N.
  246. endif
  247. if X86_64
  248. config X86_EXTENDED_PLATFORM
  249. bool "Support for extended (non-PC) x86 platforms"
  250. default y
  251. ---help---
  252. If you disable this option then the kernel will only support
  253. standard PC platforms. (which covers the vast majority of
  254. systems out there.)
  255. If you enable this option then you'll be able to select support
  256. for the following (non-PC) 64 bit x86 platforms:
  257. ScaleMP vSMP
  258. SGI Ultraviolet
  259. If you have one of these systems, or if you want to build a
  260. generic distribution kernel, say Y here - otherwise say N.
  261. endif
  262. # This is an alphabetically sorted list of 64 bit extended platforms
  263. # Please maintain the alphabetic order if and when there are additions
  264. config X86_VSMP
  265. bool "ScaleMP vSMP"
  266. select PARAVIRT
  267. depends on X86_64 && PCI
  268. depends on X86_EXTENDED_PLATFORM
  269. ---help---
  270. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  271. supposed to run on these EM64T-based machines. Only choose this option
  272. if you have one of these machines.
  273. config X86_UV
  274. bool "SGI Ultraviolet"
  275. depends on X86_64
  276. depends on X86_EXTENDED_PLATFORM
  277. depends on NUMA
  278. depends on X86_X2APIC
  279. ---help---
  280. This option is needed in order to support SGI Ultraviolet systems.
  281. If you don't have one of these, you should say N here.
  282. # Following is an alphabetically sorted list of 32 bit extended platforms
  283. # Please maintain the alphabetic order if and when there are additions
  284. config X86_ELAN
  285. bool "AMD Elan"
  286. depends on X86_32
  287. depends on X86_EXTENDED_PLATFORM
  288. ---help---
  289. Select this for an AMD Elan processor.
  290. Do not use this option for K6/Athlon/Opteron processors!
  291. If unsure, choose "PC-compatible" instead.
  292. config X86_RDC321X
  293. bool "RDC R-321x SoC"
  294. depends on X86_32
  295. depends on X86_EXTENDED_PLATFORM
  296. select M486
  297. select X86_REBOOTFIXUPS
  298. ---help---
  299. This option is needed for RDC R-321x system-on-chip, also known
  300. as R-8610-(G).
  301. If you don't have one of these chips, you should say N here.
  302. config X86_32_NON_STANDARD
  303. bool "Support non-standard 32-bit SMP architectures"
  304. depends on X86_32 && SMP
  305. depends on X86_EXTENDED_PLATFORM
  306. ---help---
  307. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  308. subarchitectures. It is intended for a generic binary kernel.
  309. if you select them all, kernel will probe it one by one. and will
  310. fallback to default.
  311. # Alphabetically sorted list of Non standard 32 bit platforms
  312. config X86_NUMAQ
  313. bool "NUMAQ (IBM/Sequent)"
  314. depends on X86_32_NON_STANDARD
  315. select NUMA
  316. select X86_MPPARSE
  317. ---help---
  318. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  319. NUMA multiquad box. This changes the way that processors are
  320. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  321. of Flat Logical. You will need a new lynxer.elf file to flash your
  322. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  323. config X86_VISWS
  324. bool "SGI 320/540 (Visual Workstation)"
  325. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  326. depends on X86_32_NON_STANDARD
  327. ---help---
  328. The SGI Visual Workstation series is an IA32-based workstation
  329. based on SGI systems chips with some legacy PC hardware attached.
  330. Say Y here to create a kernel to run on the SGI 320 or 540.
  331. A kernel compiled for the Visual Workstation will run on general
  332. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  333. config X86_SUMMIT
  334. bool "Summit/EXA (IBM x440)"
  335. depends on X86_32_NON_STANDARD
  336. ---help---
  337. This option is needed for IBM systems that use the Summit/EXA chipset.
  338. In particular, it is needed for the x440.
  339. config X86_ES7000
  340. bool "Unisys ES7000 IA32 series"
  341. depends on X86_32_NON_STANDARD && X86_BIGSMP
  342. ---help---
  343. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  344. supposed to run on an IA32-based Unisys ES7000 system.
  345. config SCHED_OMIT_FRAME_POINTER
  346. def_bool y
  347. prompt "Single-depth WCHAN output"
  348. depends on X86
  349. ---help---
  350. Calculate simpler /proc/<PID>/wchan values. If this option
  351. is disabled then wchan values will recurse back to the
  352. caller function. This provides more accurate wchan values,
  353. at the expense of slightly more scheduling overhead.
  354. If in doubt, say "Y".
  355. menuconfig PARAVIRT_GUEST
  356. bool "Paravirtualized guest support"
  357. ---help---
  358. Say Y here to get to see options related to running Linux under
  359. various hypervisors. This option alone does not add any kernel code.
  360. If you say N, all options in this submenu will be skipped and disabled.
  361. if PARAVIRT_GUEST
  362. source "arch/x86/xen/Kconfig"
  363. config VMI
  364. bool "VMI Guest support"
  365. select PARAVIRT
  366. depends on X86_32
  367. ---help---
  368. VMI provides a paravirtualized interface to the VMware ESX server
  369. (it could be used by other hypervisors in theory too, but is not
  370. at the moment), by linking the kernel to a GPL-ed ROM module
  371. provided by the hypervisor.
  372. config KVM_CLOCK
  373. bool "KVM paravirtualized clock"
  374. select PARAVIRT
  375. select PARAVIRT_CLOCK
  376. ---help---
  377. Turning on this option will allow you to run a paravirtualized clock
  378. when running over the KVM hypervisor. Instead of relying on a PIT
  379. (or probably other) emulation by the underlying device model, the host
  380. provides the guest with timing infrastructure such as time of day, and
  381. system time
  382. config KVM_GUEST
  383. bool "KVM Guest support"
  384. select PARAVIRT
  385. ---help---
  386. This option enables various optimizations for running under the KVM
  387. hypervisor.
  388. source "arch/x86/lguest/Kconfig"
  389. config PARAVIRT
  390. bool "Enable paravirtualization code"
  391. ---help---
  392. This changes the kernel so it can modify itself when it is run
  393. under a hypervisor, potentially improving performance significantly
  394. over full virtualization. However, when run without a hypervisor
  395. the kernel is theoretically slower and slightly larger.
  396. config PARAVIRT_SPINLOCKS
  397. bool "Paravirtualization layer for spinlocks"
  398. depends on PARAVIRT && SMP && EXPERIMENTAL
  399. ---help---
  400. Paravirtualized spinlocks allow a pvops backend to replace the
  401. spinlock implementation with something virtualization-friendly
  402. (for example, block the virtual CPU rather than spinning).
  403. Unfortunately the downside is an up to 5% performance hit on
  404. native kernels, with various workloads.
  405. If you are unsure how to answer this question, answer N.
  406. config PARAVIRT_CLOCK
  407. bool
  408. default n
  409. endif
  410. config PARAVIRT_DEBUG
  411. bool "paravirt-ops debugging"
  412. depends on PARAVIRT && DEBUG_KERNEL
  413. ---help---
  414. Enable to debug paravirt_ops internals. Specifically, BUG if
  415. a paravirt_op is missing when it is called.
  416. config MEMTEST
  417. bool "Memtest"
  418. ---help---
  419. This option adds a kernel parameter 'memtest', which allows memtest
  420. to be set.
  421. memtest=0, mean disabled; -- default
  422. memtest=1, mean do 1 test pattern;
  423. ...
  424. memtest=4, mean do 4 test patterns.
  425. If you are unsure how to answer this question, answer N.
  426. config X86_SUMMIT_NUMA
  427. def_bool y
  428. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  429. config X86_CYCLONE_TIMER
  430. def_bool y
  431. depends on X86_32_NON_STANDARD
  432. source "arch/x86/Kconfig.cpu"
  433. config HPET_TIMER
  434. def_bool X86_64
  435. prompt "HPET Timer Support" if X86_32
  436. ---help---
  437. Use the IA-PC HPET (High Precision Event Timer) to manage
  438. time in preference to the PIT and RTC, if a HPET is
  439. present.
  440. HPET is the next generation timer replacing legacy 8254s.
  441. The HPET provides a stable time base on SMP
  442. systems, unlike the TSC, but it is more expensive to access,
  443. as it is off-chip. You can find the HPET spec at
  444. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  445. You can safely choose Y here. However, HPET will only be
  446. activated if the platform and the BIOS support this feature.
  447. Otherwise the 8254 will be used for timing services.
  448. Choose N to continue using the legacy 8254 timer.
  449. config HPET_EMULATE_RTC
  450. def_bool y
  451. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  452. # Mark as embedded because too many people got it wrong.
  453. # The code disables itself when not needed.
  454. config DMI
  455. default y
  456. bool "Enable DMI scanning" if EMBEDDED
  457. ---help---
  458. Enabled scanning of DMI to identify machine quirks. Say Y
  459. here unless you have verified that your setup is not
  460. affected by entries in the DMI blacklist. Required by PNP
  461. BIOS code.
  462. config GART_IOMMU
  463. bool "GART IOMMU support" if EMBEDDED
  464. default y
  465. select SWIOTLB
  466. select AGP
  467. depends on X86_64 && PCI
  468. ---help---
  469. Support for full DMA access of devices with 32bit memory access only
  470. on systems with more than 3GB. This is usually needed for USB,
  471. sound, many IDE/SATA chipsets and some other devices.
  472. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  473. based hardware IOMMU and a software bounce buffer based IOMMU used
  474. on Intel systems and as fallback.
  475. The code is only active when needed (enough memory and limited
  476. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  477. too.
  478. config CALGARY_IOMMU
  479. bool "IBM Calgary IOMMU support"
  480. select SWIOTLB
  481. depends on X86_64 && PCI && EXPERIMENTAL
  482. ---help---
  483. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  484. systems. Needed to run systems with more than 3GB of memory
  485. properly with 32-bit PCI devices that do not support DAC
  486. (Double Address Cycle). Calgary also supports bus level
  487. isolation, where all DMAs pass through the IOMMU. This
  488. prevents them from going anywhere except their intended
  489. destination. This catches hard-to-find kernel bugs and
  490. mis-behaving drivers and devices that do not use the DMA-API
  491. properly to set up their DMA buffers. The IOMMU can be
  492. turned off at boot time with the iommu=off parameter.
  493. Normally the kernel will make the right choice by itself.
  494. If unsure, say Y.
  495. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  496. def_bool y
  497. prompt "Should Calgary be enabled by default?"
  498. depends on CALGARY_IOMMU
  499. ---help---
  500. Should Calgary be enabled by default? if you choose 'y', Calgary
  501. will be used (if it exists). If you choose 'n', Calgary will not be
  502. used even if it exists. If you choose 'n' and would like to use
  503. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  504. If unsure, say Y.
  505. config AMD_IOMMU
  506. bool "AMD IOMMU support"
  507. select SWIOTLB
  508. select PCI_MSI
  509. depends on X86_64 && PCI && ACPI
  510. ---help---
  511. With this option you can enable support for AMD IOMMU hardware in
  512. your system. An IOMMU is a hardware component which provides
  513. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  514. can isolate the the DMA memory of different devices and protect the
  515. system from misbehaving device drivers or hardware.
  516. You can find out if your system has an AMD IOMMU if you look into
  517. your BIOS for an option to enable it or if you have an IVRS ACPI
  518. table.
  519. config AMD_IOMMU_STATS
  520. bool "Export AMD IOMMU statistics to debugfs"
  521. depends on AMD_IOMMU
  522. select DEBUG_FS
  523. ---help---
  524. This option enables code in the AMD IOMMU driver to collect various
  525. statistics about whats happening in the driver and exports that
  526. information to userspace via debugfs.
  527. If unsure, say N.
  528. # need this always selected by IOMMU for the VIA workaround
  529. config SWIOTLB
  530. def_bool y if X86_64
  531. ---help---
  532. Support for software bounce buffers used on x86-64 systems
  533. which don't have a hardware IOMMU (e.g. the current generation
  534. of Intel's x86-64 CPUs). Using this PCI devices which can only
  535. access 32-bits of memory can be used on systems with more than
  536. 3 GB of memory. If unsure, say Y.
  537. config IOMMU_HELPER
  538. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  539. config IOMMU_API
  540. def_bool (AMD_IOMMU || DMAR)
  541. config MAXSMP
  542. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  543. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  544. select CPUMASK_OFFSTACK
  545. default n
  546. ---help---
  547. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  548. If unsure, say N.
  549. config NR_CPUS
  550. int "Maximum number of CPUs" if SMP && !MAXSMP
  551. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  552. range 2 512 if SMP && !MAXSMP
  553. default "1" if !SMP
  554. default "4096" if MAXSMP
  555. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  556. default "8" if SMP
  557. ---help---
  558. This allows you to specify the maximum number of CPUs which this
  559. kernel will support. The maximum supported value is 512 and the
  560. minimum value which makes sense is 2.
  561. This is purely to save memory - each supported CPU adds
  562. approximately eight kilobytes to the kernel image.
  563. config SCHED_SMT
  564. bool "SMT (Hyperthreading) scheduler support"
  565. depends on X86_HT
  566. ---help---
  567. SMT scheduler support improves the CPU scheduler's decision making
  568. when dealing with Intel Pentium 4 chips with HyperThreading at a
  569. cost of slightly increased overhead in some places. If unsure say
  570. N here.
  571. config SCHED_MC
  572. def_bool y
  573. prompt "Multi-core scheduler support"
  574. depends on X86_HT
  575. ---help---
  576. Multi-core scheduler support improves the CPU scheduler's decision
  577. making when dealing with multi-core CPU chips at a cost of slightly
  578. increased overhead in some places. If unsure say N here.
  579. source "kernel/Kconfig.preempt"
  580. config X86_UP_APIC
  581. bool "Local APIC support on uniprocessors"
  582. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  583. ---help---
  584. A local APIC (Advanced Programmable Interrupt Controller) is an
  585. integrated interrupt controller in the CPU. If you have a single-CPU
  586. system which has a processor with a local APIC, you can say Y here to
  587. enable and use it. If you say Y here even though your machine doesn't
  588. have a local APIC, then the kernel will still run with no slowdown at
  589. all. The local APIC supports CPU-generated self-interrupts (timer,
  590. performance counters), and the NMI watchdog which detects hard
  591. lockups.
  592. config X86_UP_IOAPIC
  593. bool "IO-APIC support on uniprocessors"
  594. depends on X86_UP_APIC
  595. ---help---
  596. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  597. SMP-capable replacement for PC-style interrupt controllers. Most
  598. SMP systems and many recent uniprocessor systems have one.
  599. If you have a single-CPU system with an IO-APIC, you can say Y here
  600. to use it. If you say Y here even though your machine doesn't have
  601. an IO-APIC, then the kernel will still run with no slowdown at all.
  602. config X86_LOCAL_APIC
  603. def_bool y
  604. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  605. select HAVE_PERF_COUNTERS if (!M386 && !M486)
  606. config X86_IO_APIC
  607. def_bool y
  608. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  609. config X86_VISWS_APIC
  610. def_bool y
  611. depends on X86_32 && X86_VISWS
  612. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  613. bool "Reroute for broken boot IRQs"
  614. default n
  615. depends on X86_IO_APIC
  616. ---help---
  617. This option enables a workaround that fixes a source of
  618. spurious interrupts. This is recommended when threaded
  619. interrupt handling is used on systems where the generation of
  620. superfluous "boot interrupts" cannot be disabled.
  621. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  622. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  623. kernel does during interrupt handling). On chipsets where this
  624. boot IRQ generation cannot be disabled, this workaround keeps
  625. the original IRQ line masked so that only the equivalent "boot
  626. IRQ" is delivered to the CPUs. The workaround also tells the
  627. kernel to set up the IRQ handler on the boot IRQ line. In this
  628. way only one interrupt is delivered to the kernel. Otherwise
  629. the spurious second interrupt may cause the kernel to bring
  630. down (vital) interrupt lines.
  631. Only affects "broken" chipsets. Interrupt sharing may be
  632. increased on these systems.
  633. config X86_MCE
  634. bool "Machine Check Exception"
  635. ---help---
  636. Machine Check Exception support allows the processor to notify the
  637. kernel if it detects a problem (e.g. overheating, component failure).
  638. The action the kernel takes depends on the severity of the problem,
  639. ranging from a warning message on the console, to halting the machine.
  640. Your processor must be a Pentium or newer to support this - check the
  641. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  642. have a design flaw which leads to false MCE events - hence MCE is
  643. disabled on all P5 processors, unless explicitly enabled with "mce"
  644. as a boot argument. Similarly, if MCE is built in and creates a
  645. problem on some new non-standard machine, you can boot with "nomce"
  646. to disable it. MCE support simply ignores non-MCE processors like
  647. the 386 and 486, so nearly everyone can say Y here.
  648. config X86_OLD_MCE
  649. depends on X86_32 && X86_MCE
  650. bool "Use legacy machine check code (will go away)"
  651. default n
  652. select X86_ANCIENT_MCE
  653. ---help---
  654. Use the old i386 machine check code. This is merely intended for
  655. testing in a transition period. Try this if you run into any machine
  656. check related software problems, but report the problem to
  657. linux-kernel. When in doubt say no.
  658. config X86_NEW_MCE
  659. depends on X86_MCE
  660. bool
  661. default y if (!X86_OLD_MCE && X86_32) || X86_64
  662. config X86_MCE_INTEL
  663. def_bool y
  664. prompt "Intel MCE features"
  665. depends on X86_NEW_MCE && X86_LOCAL_APIC
  666. ---help---
  667. Additional support for intel specific MCE features such as
  668. the thermal monitor.
  669. config X86_MCE_AMD
  670. def_bool y
  671. prompt "AMD MCE features"
  672. depends on X86_NEW_MCE && X86_LOCAL_APIC
  673. ---help---
  674. Additional support for AMD specific MCE features such as
  675. the DRAM Error Threshold.
  676. config X86_ANCIENT_MCE
  677. def_bool n
  678. depends on X86_32
  679. prompt "Support for old Pentium 5 / WinChip machine checks"
  680. ---help---
  681. Include support for machine check handling on old Pentium 5 or WinChip
  682. systems. These typically need to be enabled explicitely on the command
  683. line.
  684. config X86_MCE_THRESHOLD
  685. depends on X86_MCE_AMD || X86_MCE_INTEL
  686. bool
  687. default y
  688. config X86_MCE_INJECT
  689. depends on X86_NEW_MCE
  690. tristate "Machine check injector support"
  691. ---help---
  692. Provide support for injecting machine checks for testing purposes.
  693. If you don't know what a machine check is and you don't do kernel
  694. QA it is safe to say n.
  695. config X86_MCE_NONFATAL
  696. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  697. depends on X86_OLD_MCE
  698. ---help---
  699. Enabling this feature starts a timer that triggers every 5 seconds which
  700. will look at the machine check registers to see if anything happened.
  701. Non-fatal problems automatically get corrected (but still logged).
  702. Disable this if you don't want to see these messages.
  703. Seeing the messages this option prints out may be indicative of dying
  704. or out-of-spec (ie, overclocked) hardware.
  705. This option only does something on certain CPUs.
  706. (AMD Athlon/Duron and Intel Pentium 4)
  707. config X86_MCE_P4THERMAL
  708. bool "check for P4 thermal throttling interrupt."
  709. depends on X86_OLD_MCE && X86_MCE && (X86_UP_APIC || SMP)
  710. ---help---
  711. Enabling this feature will cause a message to be printed when the P4
  712. enters thermal throttling.
  713. config X86_THERMAL_VECTOR
  714. def_bool y
  715. depends on X86_MCE_P4THERMAL || X86_MCE_INTEL
  716. config VM86
  717. bool "Enable VM86 support" if EMBEDDED
  718. default y
  719. depends on X86_32
  720. ---help---
  721. This option is required by programs like DOSEMU to run 16-bit legacy
  722. code on X86 processors. It also may be needed by software like
  723. XFree86 to initialize some video cards via BIOS. Disabling this
  724. option saves about 6k.
  725. config TOSHIBA
  726. tristate "Toshiba Laptop support"
  727. depends on X86_32
  728. ---help---
  729. This adds a driver to safely access the System Management Mode of
  730. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  731. not work on models with a Phoenix BIOS. The System Management Mode
  732. is used to set the BIOS and power saving options on Toshiba portables.
  733. For information on utilities to make use of this driver see the
  734. Toshiba Linux utilities web site at:
  735. <http://www.buzzard.org.uk/toshiba/>.
  736. Say Y if you intend to run this kernel on a Toshiba portable.
  737. Say N otherwise.
  738. config I8K
  739. tristate "Dell laptop support"
  740. ---help---
  741. This adds a driver to safely access the System Management Mode
  742. of the CPU on the Dell Inspiron 8000. The System Management Mode
  743. is used to read cpu temperature and cooling fan status and to
  744. control the fans on the I8K portables.
  745. This driver has been tested only on the Inspiron 8000 but it may
  746. also work with other Dell laptops. You can force loading on other
  747. models by passing the parameter `force=1' to the module. Use at
  748. your own risk.
  749. For information on utilities to make use of this driver see the
  750. I8K Linux utilities web site at:
  751. <http://people.debian.org/~dz/i8k/>
  752. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  753. Say N otherwise.
  754. config X86_REBOOTFIXUPS
  755. bool "Enable X86 board specific fixups for reboot"
  756. depends on X86_32
  757. ---help---
  758. This enables chipset and/or board specific fixups to be done
  759. in order to get reboot to work correctly. This is only needed on
  760. some combinations of hardware and BIOS. The symptom, for which
  761. this config is intended, is when reboot ends with a stalled/hung
  762. system.
  763. Currently, the only fixup is for the Geode machines using
  764. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  765. Say Y if you want to enable the fixup. Currently, it's safe to
  766. enable this option even if you don't need it.
  767. Say N otherwise.
  768. config MICROCODE
  769. tristate "/dev/cpu/microcode - microcode support"
  770. select FW_LOADER
  771. ---help---
  772. If you say Y here, you will be able to update the microcode on
  773. certain Intel and AMD processors. The Intel support is for the
  774. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  775. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  776. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  777. You will obviously need the actual microcode binary data itself
  778. which is not shipped with the Linux kernel.
  779. This option selects the general module only, you need to select
  780. at least one vendor specific module as well.
  781. To compile this driver as a module, choose M here: the
  782. module will be called microcode.
  783. config MICROCODE_INTEL
  784. bool "Intel microcode patch loading support"
  785. depends on MICROCODE
  786. default MICROCODE
  787. select FW_LOADER
  788. ---help---
  789. This options enables microcode patch loading support for Intel
  790. processors.
  791. For latest news and information on obtaining all the required
  792. Intel ingredients for this driver, check:
  793. <http://www.urbanmyth.org/microcode/>.
  794. config MICROCODE_AMD
  795. bool "AMD microcode patch loading support"
  796. depends on MICROCODE
  797. select FW_LOADER
  798. ---help---
  799. If you select this option, microcode patch loading support for AMD
  800. processors will be enabled.
  801. config MICROCODE_OLD_INTERFACE
  802. def_bool y
  803. depends on MICROCODE
  804. config X86_MSR
  805. tristate "/dev/cpu/*/msr - Model-specific register support"
  806. ---help---
  807. This device gives privileged processes access to the x86
  808. Model-Specific Registers (MSRs). It is a character device with
  809. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  810. MSR accesses are directed to a specific CPU on multi-processor
  811. systems.
  812. config X86_CPUID
  813. tristate "/dev/cpu/*/cpuid - CPU information support"
  814. ---help---
  815. This device gives processes access to the x86 CPUID instruction to
  816. be executed on a specific processor. It is a character device
  817. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  818. /dev/cpu/31/cpuid.
  819. config X86_CPU_DEBUG
  820. tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
  821. ---help---
  822. If you select this option, this will provide various x86 CPUs
  823. information through debugfs.
  824. choice
  825. prompt "High Memory Support"
  826. default HIGHMEM4G if !X86_NUMAQ
  827. default HIGHMEM64G if X86_NUMAQ
  828. depends on X86_32
  829. config NOHIGHMEM
  830. bool "off"
  831. depends on !X86_NUMAQ
  832. ---help---
  833. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  834. However, the address space of 32-bit x86 processors is only 4
  835. Gigabytes large. That means that, if you have a large amount of
  836. physical memory, not all of it can be "permanently mapped" by the
  837. kernel. The physical memory that's not permanently mapped is called
  838. "high memory".
  839. If you are compiling a kernel which will never run on a machine with
  840. more than 1 Gigabyte total physical RAM, answer "off" here (default
  841. choice and suitable for most users). This will result in a "3GB/1GB"
  842. split: 3GB are mapped so that each process sees a 3GB virtual memory
  843. space and the remaining part of the 4GB virtual memory space is used
  844. by the kernel to permanently map as much physical memory as
  845. possible.
  846. If the machine has between 1 and 4 Gigabytes physical RAM, then
  847. answer "4GB" here.
  848. If more than 4 Gigabytes is used then answer "64GB" here. This
  849. selection turns Intel PAE (Physical Address Extension) mode on.
  850. PAE implements 3-level paging on IA32 processors. PAE is fully
  851. supported by Linux, PAE mode is implemented on all recent Intel
  852. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  853. then the kernel will not boot on CPUs that don't support PAE!
  854. The actual amount of total physical memory will either be
  855. auto detected or can be forced by using a kernel command line option
  856. such as "mem=256M". (Try "man bootparam" or see the documentation of
  857. your boot loader (lilo or loadlin) about how to pass options to the
  858. kernel at boot time.)
  859. If unsure, say "off".
  860. config HIGHMEM4G
  861. bool "4GB"
  862. depends on !X86_NUMAQ
  863. ---help---
  864. Select this if you have a 32-bit processor and between 1 and 4
  865. gigabytes of physical RAM.
  866. config HIGHMEM64G
  867. bool "64GB"
  868. depends on !M386 && !M486
  869. select X86_PAE
  870. ---help---
  871. Select this if you have a 32-bit processor and more than 4
  872. gigabytes of physical RAM.
  873. endchoice
  874. choice
  875. depends on EXPERIMENTAL
  876. prompt "Memory split" if EMBEDDED
  877. default VMSPLIT_3G
  878. depends on X86_32
  879. ---help---
  880. Select the desired split between kernel and user memory.
  881. If the address range available to the kernel is less than the
  882. physical memory installed, the remaining memory will be available
  883. as "high memory". Accessing high memory is a little more costly
  884. than low memory, as it needs to be mapped into the kernel first.
  885. Note that increasing the kernel address space limits the range
  886. available to user programs, making the address space there
  887. tighter. Selecting anything other than the default 3G/1G split
  888. will also likely make your kernel incompatible with binary-only
  889. kernel modules.
  890. If you are not absolutely sure what you are doing, leave this
  891. option alone!
  892. config VMSPLIT_3G
  893. bool "3G/1G user/kernel split"
  894. config VMSPLIT_3G_OPT
  895. depends on !X86_PAE
  896. bool "3G/1G user/kernel split (for full 1G low memory)"
  897. config VMSPLIT_2G
  898. bool "2G/2G user/kernel split"
  899. config VMSPLIT_2G_OPT
  900. depends on !X86_PAE
  901. bool "2G/2G user/kernel split (for full 2G low memory)"
  902. config VMSPLIT_1G
  903. bool "1G/3G user/kernel split"
  904. endchoice
  905. config PAGE_OFFSET
  906. hex
  907. default 0xB0000000 if VMSPLIT_3G_OPT
  908. default 0x80000000 if VMSPLIT_2G
  909. default 0x78000000 if VMSPLIT_2G_OPT
  910. default 0x40000000 if VMSPLIT_1G
  911. default 0xC0000000
  912. depends on X86_32
  913. config HIGHMEM
  914. def_bool y
  915. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  916. config X86_PAE
  917. bool "PAE (Physical Address Extension) Support"
  918. depends on X86_32 && !HIGHMEM4G
  919. ---help---
  920. PAE is required for NX support, and furthermore enables
  921. larger swapspace support for non-overcommit purposes. It
  922. has the cost of more pagetable lookup overhead, and also
  923. consumes more pagetable space per process.
  924. config ARCH_PHYS_ADDR_T_64BIT
  925. def_bool X86_64 || X86_PAE
  926. config DIRECT_GBPAGES
  927. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  928. default y
  929. depends on X86_64
  930. ---help---
  931. Allow the kernel linear mapping to use 1GB pages on CPUs that
  932. support it. This can improve the kernel's performance a tiny bit by
  933. reducing TLB pressure. If in doubt, say "Y".
  934. # Common NUMA Features
  935. config NUMA
  936. bool "Numa Memory Allocation and Scheduler Support"
  937. depends on SMP
  938. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  939. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  940. ---help---
  941. Enable NUMA (Non Uniform Memory Access) support.
  942. The kernel will try to allocate memory used by a CPU on the
  943. local memory controller of the CPU and add some more
  944. NUMA awareness to the kernel.
  945. For 64-bit this is recommended if the system is Intel Core i7
  946. (or later), AMD Opteron, or EM64T NUMA.
  947. For 32-bit this is only needed on (rare) 32-bit-only platforms
  948. that support NUMA topologies, such as NUMAQ / Summit, or if you
  949. boot a 32-bit kernel on a 64-bit NUMA platform.
  950. Otherwise, you should say N.
  951. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  952. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  953. config K8_NUMA
  954. def_bool y
  955. prompt "Old style AMD Opteron NUMA detection"
  956. depends on X86_64 && NUMA && PCI
  957. ---help---
  958. Enable K8 NUMA node topology detection. You should say Y here if
  959. you have a multi processor AMD K8 system. This uses an old
  960. method to read the NUMA configuration directly from the builtin
  961. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  962. instead, which also takes priority if both are compiled in.
  963. config X86_64_ACPI_NUMA
  964. def_bool y
  965. prompt "ACPI NUMA detection"
  966. depends on X86_64 && NUMA && ACPI && PCI
  967. select ACPI_NUMA
  968. ---help---
  969. Enable ACPI SRAT based node topology detection.
  970. # Some NUMA nodes have memory ranges that span
  971. # other nodes. Even though a pfn is valid and
  972. # between a node's start and end pfns, it may not
  973. # reside on that node. See memmap_init_zone()
  974. # for details.
  975. config NODES_SPAN_OTHER_NODES
  976. def_bool y
  977. depends on X86_64_ACPI_NUMA
  978. config NUMA_EMU
  979. bool "NUMA emulation"
  980. depends on X86_64 && NUMA
  981. ---help---
  982. Enable NUMA emulation. A flat machine will be split
  983. into virtual nodes when booted with "numa=fake=N", where N is the
  984. number of nodes. This is only useful for debugging.
  985. config NODES_SHIFT
  986. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  987. range 1 9
  988. default "9" if MAXSMP
  989. default "6" if X86_64
  990. default "4" if X86_NUMAQ
  991. default "3"
  992. depends on NEED_MULTIPLE_NODES
  993. ---help---
  994. Specify the maximum number of NUMA Nodes available on the target
  995. system. Increases memory reserved to accommodate various tables.
  996. config HAVE_ARCH_BOOTMEM
  997. def_bool y
  998. depends on X86_32 && NUMA
  999. config ARCH_HAVE_MEMORY_PRESENT
  1000. def_bool y
  1001. depends on X86_32 && DISCONTIGMEM
  1002. config NEED_NODE_MEMMAP_SIZE
  1003. def_bool y
  1004. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1005. config HAVE_ARCH_ALLOC_REMAP
  1006. def_bool y
  1007. depends on X86_32 && NUMA
  1008. config ARCH_FLATMEM_ENABLE
  1009. def_bool y
  1010. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1011. config ARCH_DISCONTIGMEM_ENABLE
  1012. def_bool y
  1013. depends on NUMA && X86_32
  1014. config ARCH_DISCONTIGMEM_DEFAULT
  1015. def_bool y
  1016. depends on NUMA && X86_32
  1017. config ARCH_SPARSEMEM_DEFAULT
  1018. def_bool y
  1019. depends on X86_64
  1020. config ARCH_SPARSEMEM_ENABLE
  1021. def_bool y
  1022. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1023. select SPARSEMEM_STATIC if X86_32
  1024. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1025. config ARCH_SELECT_MEMORY_MODEL
  1026. def_bool y
  1027. depends on ARCH_SPARSEMEM_ENABLE
  1028. config ARCH_MEMORY_PROBE
  1029. def_bool X86_64
  1030. depends on MEMORY_HOTPLUG
  1031. source "mm/Kconfig"
  1032. config HIGHPTE
  1033. bool "Allocate 3rd-level pagetables from highmem"
  1034. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  1035. ---help---
  1036. The VM uses one page table entry for each page of physical memory.
  1037. For systems with a lot of RAM, this can be wasteful of precious
  1038. low memory. Setting this option will put user-space page table
  1039. entries in high memory.
  1040. config X86_CHECK_BIOS_CORRUPTION
  1041. bool "Check for low memory corruption"
  1042. ---help---
  1043. Periodically check for memory corruption in low memory, which
  1044. is suspected to be caused by BIOS. Even when enabled in the
  1045. configuration, it is disabled at runtime. Enable it by
  1046. setting "memory_corruption_check=1" on the kernel command
  1047. line. By default it scans the low 64k of memory every 60
  1048. seconds; see the memory_corruption_check_size and
  1049. memory_corruption_check_period parameters in
  1050. Documentation/kernel-parameters.txt to adjust this.
  1051. When enabled with the default parameters, this option has
  1052. almost no overhead, as it reserves a relatively small amount
  1053. of memory and scans it infrequently. It both detects corruption
  1054. and prevents it from affecting the running system.
  1055. It is, however, intended as a diagnostic tool; if repeatable
  1056. BIOS-originated corruption always affects the same memory,
  1057. you can use memmap= to prevent the kernel from using that
  1058. memory.
  1059. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1060. bool "Set the default setting of memory_corruption_check"
  1061. depends on X86_CHECK_BIOS_CORRUPTION
  1062. default y
  1063. ---help---
  1064. Set whether the default state of memory_corruption_check is
  1065. on or off.
  1066. config X86_RESERVE_LOW_64K
  1067. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1068. default y
  1069. ---help---
  1070. Reserve the first 64K of physical RAM on BIOSes that are known
  1071. to potentially corrupt that memory range. A numbers of BIOSes are
  1072. known to utilize this area during suspend/resume, so it must not
  1073. be used by the kernel.
  1074. Set this to N if you are absolutely sure that you trust the BIOS
  1075. to get all its memory reservations and usages right.
  1076. If you have doubts about the BIOS (e.g. suspend/resume does not
  1077. work or there's kernel crashes after certain hardware hotplug
  1078. events) and it's not AMI or Phoenix, then you might want to enable
  1079. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1080. corruption patterns.
  1081. Say Y if unsure.
  1082. config MATH_EMULATION
  1083. bool
  1084. prompt "Math emulation" if X86_32
  1085. ---help---
  1086. Linux can emulate a math coprocessor (used for floating point
  1087. operations) if you don't have one. 486DX and Pentium processors have
  1088. a math coprocessor built in, 486SX and 386 do not, unless you added
  1089. a 487DX or 387, respectively. (The messages during boot time can
  1090. give you some hints here ["man dmesg"].) Everyone needs either a
  1091. coprocessor or this emulation.
  1092. If you don't have a math coprocessor, you need to say Y here; if you
  1093. say Y here even though you have a coprocessor, the coprocessor will
  1094. be used nevertheless. (This behavior can be changed with the kernel
  1095. command line option "no387", which comes handy if your coprocessor
  1096. is broken. Try "man bootparam" or see the documentation of your boot
  1097. loader (lilo or loadlin) about how to pass options to the kernel at
  1098. boot time.) This means that it is a good idea to say Y here if you
  1099. intend to use this kernel on different machines.
  1100. More information about the internals of the Linux math coprocessor
  1101. emulation can be found in <file:arch/x86/math-emu/README>.
  1102. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1103. kernel, it won't hurt.
  1104. config MTRR
  1105. bool "MTRR (Memory Type Range Register) support"
  1106. ---help---
  1107. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1108. the Memory Type Range Registers (MTRRs) may be used to control
  1109. processor access to memory ranges. This is most useful if you have
  1110. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1111. allows bus write transfers to be combined into a larger transfer
  1112. before bursting over the PCI/AGP bus. This can increase performance
  1113. of image write operations 2.5 times or more. Saying Y here creates a
  1114. /proc/mtrr file which may be used to manipulate your processor's
  1115. MTRRs. Typically the X server should use this.
  1116. This code has a reasonably generic interface so that similar
  1117. control registers on other processors can be easily supported
  1118. as well:
  1119. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1120. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1121. these, the ARRs are used to emulate the MTRRs.
  1122. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1123. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1124. write-combining. All of these processors are supported by this code
  1125. and it makes sense to say Y here if you have one of them.
  1126. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1127. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1128. can lead to all sorts of problems, so it's good to say Y here.
  1129. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1130. just add about 9 KB to your kernel.
  1131. See <file:Documentation/x86/mtrr.txt> for more information.
  1132. config MTRR_SANITIZER
  1133. def_bool y
  1134. prompt "MTRR cleanup support"
  1135. depends on MTRR
  1136. ---help---
  1137. Convert MTRR layout from continuous to discrete, so X drivers can
  1138. add writeback entries.
  1139. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1140. The largest mtrr entry size for a continuous block can be set with
  1141. mtrr_chunk_size.
  1142. If unsure, say Y.
  1143. config MTRR_SANITIZER_ENABLE_DEFAULT
  1144. int "MTRR cleanup enable value (0-1)"
  1145. range 0 1
  1146. default "0"
  1147. depends on MTRR_SANITIZER
  1148. ---help---
  1149. Enable mtrr cleanup default value
  1150. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1151. int "MTRR cleanup spare reg num (0-7)"
  1152. range 0 7
  1153. default "1"
  1154. depends on MTRR_SANITIZER
  1155. ---help---
  1156. mtrr cleanup spare entries default, it can be changed via
  1157. mtrr_spare_reg_nr=N on the kernel command line.
  1158. config X86_PAT
  1159. bool
  1160. prompt "x86 PAT support"
  1161. depends on MTRR
  1162. ---help---
  1163. Use PAT attributes to setup page level cache control.
  1164. PATs are the modern equivalents of MTRRs and are much more
  1165. flexible than MTRRs.
  1166. Say N here if you see bootup problems (boot crash, boot hang,
  1167. spontaneous reboots) or a non-working video driver.
  1168. If unsure, say Y.
  1169. config EFI
  1170. bool "EFI runtime service support"
  1171. depends on ACPI
  1172. ---help---
  1173. This enables the kernel to use EFI runtime services that are
  1174. available (such as the EFI variable services).
  1175. This option is only useful on systems that have EFI firmware.
  1176. In addition, you should use the latest ELILO loader available
  1177. at <http://elilo.sourceforge.net> in order to take advantage
  1178. of EFI runtime services. However, even with this option, the
  1179. resultant kernel should continue to boot on existing non-EFI
  1180. platforms.
  1181. config SECCOMP
  1182. def_bool y
  1183. prompt "Enable seccomp to safely compute untrusted bytecode"
  1184. ---help---
  1185. This kernel feature is useful for number crunching applications
  1186. that may need to compute untrusted bytecode during their
  1187. execution. By using pipes or other transports made available to
  1188. the process as file descriptors supporting the read/write
  1189. syscalls, it's possible to isolate those applications in
  1190. their own address space using seccomp. Once seccomp is
  1191. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1192. and the task is only allowed to execute a few safe syscalls
  1193. defined by each seccomp mode.
  1194. If unsure, say Y. Only embedded should say N here.
  1195. config CC_STACKPROTECTOR_ALL
  1196. bool
  1197. config CC_STACKPROTECTOR
  1198. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1199. select CC_STACKPROTECTOR_ALL
  1200. ---help---
  1201. This option turns on the -fstack-protector GCC feature. This
  1202. feature puts, at the beginning of functions, a canary value on
  1203. the stack just before the return address, and validates
  1204. the value just before actually returning. Stack based buffer
  1205. overflows (that need to overwrite this return address) now also
  1206. overwrite the canary, which gets detected and the attack is then
  1207. neutralized via a kernel panic.
  1208. This feature requires gcc version 4.2 or above, or a distribution
  1209. gcc with the feature backported. Older versions are automatically
  1210. detected and for those versions, this configuration option is
  1211. ignored. (and a warning is printed during bootup)
  1212. source kernel/Kconfig.hz
  1213. config KEXEC
  1214. bool "kexec system call"
  1215. ---help---
  1216. kexec is a system call that implements the ability to shutdown your
  1217. current kernel, and to start another kernel. It is like a reboot
  1218. but it is independent of the system firmware. And like a reboot
  1219. you can start any kernel with it, not just Linux.
  1220. The name comes from the similarity to the exec system call.
  1221. It is an ongoing process to be certain the hardware in a machine
  1222. is properly shutdown, so do not be surprised if this code does not
  1223. initially work for you. It may help to enable device hotplugging
  1224. support. As of this writing the exact hardware interface is
  1225. strongly in flux, so no good recommendation can be made.
  1226. config CRASH_DUMP
  1227. bool "kernel crash dumps"
  1228. depends on X86_64 || (X86_32 && HIGHMEM)
  1229. ---help---
  1230. Generate crash dump after being started by kexec.
  1231. This should be normally only set in special crash dump kernels
  1232. which are loaded in the main kernel with kexec-tools into
  1233. a specially reserved region and then later executed after
  1234. a crash by kdump/kexec. The crash dump kernel must be compiled
  1235. to a memory address not used by the main kernel or BIOS using
  1236. PHYSICAL_START, or it must be built as a relocatable image
  1237. (CONFIG_RELOCATABLE=y).
  1238. For more details see Documentation/kdump/kdump.txt
  1239. config KEXEC_JUMP
  1240. bool "kexec jump (EXPERIMENTAL)"
  1241. depends on EXPERIMENTAL
  1242. depends on KEXEC && HIBERNATION
  1243. ---help---
  1244. Jump between original kernel and kexeced kernel and invoke
  1245. code in physical address mode via KEXEC
  1246. config PHYSICAL_START
  1247. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1248. default "0x1000000"
  1249. ---help---
  1250. This gives the physical address where the kernel is loaded.
  1251. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1252. bzImage will decompress itself to above physical address and
  1253. run from there. Otherwise, bzImage will run from the address where
  1254. it has been loaded by the boot loader and will ignore above physical
  1255. address.
  1256. In normal kdump cases one does not have to set/change this option
  1257. as now bzImage can be compiled as a completely relocatable image
  1258. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1259. address. This option is mainly useful for the folks who don't want
  1260. to use a bzImage for capturing the crash dump and want to use a
  1261. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1262. to be specifically compiled to run from a specific memory area
  1263. (normally a reserved region) and this option comes handy.
  1264. So if you are using bzImage for capturing the crash dump,
  1265. leave the value here unchanged to 0x1000000 and set
  1266. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1267. for capturing the crash dump change this value to start of
  1268. the reserved region. In other words, it can be set based on
  1269. the "X" value as specified in the "crashkernel=YM@XM"
  1270. command line boot parameter passed to the panic-ed
  1271. kernel. Please take a look at Documentation/kdump/kdump.txt
  1272. for more details about crash dumps.
  1273. Usage of bzImage for capturing the crash dump is recommended as
  1274. one does not have to build two kernels. Same kernel can be used
  1275. as production kernel and capture kernel. Above option should have
  1276. gone away after relocatable bzImage support is introduced. But it
  1277. is present because there are users out there who continue to use
  1278. vmlinux for dump capture. This option should go away down the
  1279. line.
  1280. Don't change this unless you know what you are doing.
  1281. config RELOCATABLE
  1282. bool "Build a relocatable kernel"
  1283. default y
  1284. ---help---
  1285. This builds a kernel image that retains relocation information
  1286. so it can be loaded someplace besides the default 1MB.
  1287. The relocations tend to make the kernel binary about 10% larger,
  1288. but are discarded at runtime.
  1289. One use is for the kexec on panic case where the recovery kernel
  1290. must live at a different physical address than the primary
  1291. kernel.
  1292. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1293. it has been loaded at and the compile time physical address
  1294. (CONFIG_PHYSICAL_START) is ignored.
  1295. # Relocation on x86-32 needs some additional build support
  1296. config X86_NEED_RELOCS
  1297. def_bool y
  1298. depends on X86_32 && RELOCATABLE
  1299. config PHYSICAL_ALIGN
  1300. hex
  1301. prompt "Alignment value to which kernel should be aligned" if X86_32
  1302. default "0x1000000"
  1303. range 0x2000 0x1000000
  1304. ---help---
  1305. This value puts the alignment restrictions on physical address
  1306. where kernel is loaded and run from. Kernel is compiled for an
  1307. address which meets above alignment restriction.
  1308. If bootloader loads the kernel at a non-aligned address and
  1309. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1310. address aligned to above value and run from there.
  1311. If bootloader loads the kernel at a non-aligned address and
  1312. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1313. load address and decompress itself to the address it has been
  1314. compiled for and run from there. The address for which kernel is
  1315. compiled already meets above alignment restrictions. Hence the
  1316. end result is that kernel runs from a physical address meeting
  1317. above alignment restrictions.
  1318. Don't change this unless you know what you are doing.
  1319. config HOTPLUG_CPU
  1320. bool "Support for hot-pluggable CPUs"
  1321. depends on SMP && HOTPLUG
  1322. ---help---
  1323. Say Y here to allow turning CPUs off and on. CPUs can be
  1324. controlled through /sys/devices/system/cpu.
  1325. ( Note: power management support will enable this option
  1326. automatically on SMP systems. )
  1327. Say N if you want to disable CPU hotplug.
  1328. config COMPAT_VDSO
  1329. def_bool y
  1330. prompt "Compat VDSO support"
  1331. depends on X86_32 || IA32_EMULATION
  1332. ---help---
  1333. Map the 32-bit VDSO to the predictable old-style address too.
  1334. ---help---
  1335. Say N here if you are running a sufficiently recent glibc
  1336. version (2.3.3 or later), to remove the high-mapped
  1337. VDSO mapping and to exclusively use the randomized VDSO.
  1338. If unsure, say Y.
  1339. config CMDLINE_BOOL
  1340. bool "Built-in kernel command line"
  1341. default n
  1342. ---help---
  1343. Allow for specifying boot arguments to the kernel at
  1344. build time. On some systems (e.g. embedded ones), it is
  1345. necessary or convenient to provide some or all of the
  1346. kernel boot arguments with the kernel itself (that is,
  1347. to not rely on the boot loader to provide them.)
  1348. To compile command line arguments into the kernel,
  1349. set this option to 'Y', then fill in the
  1350. the boot arguments in CONFIG_CMDLINE.
  1351. Systems with fully functional boot loaders (i.e. non-embedded)
  1352. should leave this option set to 'N'.
  1353. config CMDLINE
  1354. string "Built-in kernel command string"
  1355. depends on CMDLINE_BOOL
  1356. default ""
  1357. ---help---
  1358. Enter arguments here that should be compiled into the kernel
  1359. image and used at boot time. If the boot loader provides a
  1360. command line at boot time, it is appended to this string to
  1361. form the full kernel command line, when the system boots.
  1362. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1363. change this behavior.
  1364. In most cases, the command line (whether built-in or provided
  1365. by the boot loader) should specify the device for the root
  1366. file system.
  1367. config CMDLINE_OVERRIDE
  1368. bool "Built-in command line overrides boot loader arguments"
  1369. default n
  1370. depends on CMDLINE_BOOL
  1371. ---help---
  1372. Set this option to 'Y' to have the kernel ignore the boot loader
  1373. command line, and use ONLY the built-in command line.
  1374. This is used to work around broken boot loaders. This should
  1375. be set to 'N' under normal conditions.
  1376. endmenu
  1377. config ARCH_ENABLE_MEMORY_HOTPLUG
  1378. def_bool y
  1379. depends on X86_64 || (X86_32 && HIGHMEM)
  1380. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1381. def_bool y
  1382. depends on MEMORY_HOTPLUG
  1383. config HAVE_ARCH_EARLY_PFN_TO_NID
  1384. def_bool X86_64
  1385. depends on NUMA
  1386. menu "Power management and ACPI options"
  1387. config ARCH_HIBERNATION_HEADER
  1388. def_bool y
  1389. depends on X86_64 && HIBERNATION
  1390. source "kernel/power/Kconfig"
  1391. source "drivers/acpi/Kconfig"
  1392. config X86_APM_BOOT
  1393. bool
  1394. default y
  1395. depends on APM || APM_MODULE
  1396. menuconfig APM
  1397. tristate "APM (Advanced Power Management) BIOS support"
  1398. depends on X86_32 && PM_SLEEP
  1399. ---help---
  1400. APM is a BIOS specification for saving power using several different
  1401. techniques. This is mostly useful for battery powered laptops with
  1402. APM compliant BIOSes. If you say Y here, the system time will be
  1403. reset after a RESUME operation, the /proc/apm device will provide
  1404. battery status information, and user-space programs will receive
  1405. notification of APM "events" (e.g. battery status change).
  1406. If you select "Y" here, you can disable actual use of the APM
  1407. BIOS by passing the "apm=off" option to the kernel at boot time.
  1408. Note that the APM support is almost completely disabled for
  1409. machines with more than one CPU.
  1410. In order to use APM, you will need supporting software. For location
  1411. and more information, read <file:Documentation/power/pm.txt> and the
  1412. Battery Powered Linux mini-HOWTO, available from
  1413. <http://www.tldp.org/docs.html#howto>.
  1414. This driver does not spin down disk drives (see the hdparm(8)
  1415. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1416. VESA-compliant "green" monitors.
  1417. This driver does not support the TI 4000M TravelMate and the ACER
  1418. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1419. desktop machines also don't have compliant BIOSes, and this driver
  1420. may cause those machines to panic during the boot phase.
  1421. Generally, if you don't have a battery in your machine, there isn't
  1422. much point in using this driver and you should say N. If you get
  1423. random kernel OOPSes or reboots that don't seem to be related to
  1424. anything, try disabling/enabling this option (or disabling/enabling
  1425. APM in your BIOS).
  1426. Some other things you should try when experiencing seemingly random,
  1427. "weird" problems:
  1428. 1) make sure that you have enough swap space and that it is
  1429. enabled.
  1430. 2) pass the "no-hlt" option to the kernel
  1431. 3) switch on floating point emulation in the kernel and pass
  1432. the "no387" option to the kernel
  1433. 4) pass the "floppy=nodma" option to the kernel
  1434. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1435. all but the first 4 MB of RAM)
  1436. 6) make sure that the CPU is not over clocked.
  1437. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1438. 8) disable the cache from your BIOS settings
  1439. 9) install a fan for the video card or exchange video RAM
  1440. 10) install a better fan for the CPU
  1441. 11) exchange RAM chips
  1442. 12) exchange the motherboard.
  1443. To compile this driver as a module, choose M here: the
  1444. module will be called apm.
  1445. if APM
  1446. config APM_IGNORE_USER_SUSPEND
  1447. bool "Ignore USER SUSPEND"
  1448. ---help---
  1449. This option will ignore USER SUSPEND requests. On machines with a
  1450. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1451. series notebooks, it is necessary to say Y because of a BIOS bug.
  1452. config APM_DO_ENABLE
  1453. bool "Enable PM at boot time"
  1454. ---help---
  1455. Enable APM features at boot time. From page 36 of the APM BIOS
  1456. specification: "When disabled, the APM BIOS does not automatically
  1457. power manage devices, enter the Standby State, enter the Suspend
  1458. State, or take power saving steps in response to CPU Idle calls."
  1459. This driver will make CPU Idle calls when Linux is idle (unless this
  1460. feature is turned off -- see "Do CPU IDLE calls", below). This
  1461. should always save battery power, but more complicated APM features
  1462. will be dependent on your BIOS implementation. You may need to turn
  1463. this option off if your computer hangs at boot time when using APM
  1464. support, or if it beeps continuously instead of suspending. Turn
  1465. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1466. T400CDT. This is off by default since most machines do fine without
  1467. this feature.
  1468. config APM_CPU_IDLE
  1469. bool "Make CPU Idle calls when idle"
  1470. ---help---
  1471. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1472. On some machines, this can activate improved power savings, such as
  1473. a slowed CPU clock rate, when the machine is idle. These idle calls
  1474. are made after the idle loop has run for some length of time (e.g.,
  1475. 333 mS). On some machines, this will cause a hang at boot time or
  1476. whenever the CPU becomes idle. (On machines with more than one CPU,
  1477. this option does nothing.)
  1478. config APM_DISPLAY_BLANK
  1479. bool "Enable console blanking using APM"
  1480. ---help---
  1481. Enable console blanking using the APM. Some laptops can use this to
  1482. turn off the LCD backlight when the screen blanker of the Linux
  1483. virtual console blanks the screen. Note that this is only used by
  1484. the virtual console screen blanker, and won't turn off the backlight
  1485. when using the X Window system. This also doesn't have anything to
  1486. do with your VESA-compliant power-saving monitor. Further, this
  1487. option doesn't work for all laptops -- it might not turn off your
  1488. backlight at all, or it might print a lot of errors to the console,
  1489. especially if you are using gpm.
  1490. config APM_ALLOW_INTS
  1491. bool "Allow interrupts during APM BIOS calls"
  1492. ---help---
  1493. Normally we disable external interrupts while we are making calls to
  1494. the APM BIOS as a measure to lessen the effects of a badly behaving
  1495. BIOS implementation. The BIOS should reenable interrupts if it
  1496. needs to. Unfortunately, some BIOSes do not -- especially those in
  1497. many of the newer IBM Thinkpads. If you experience hangs when you
  1498. suspend, try setting this to Y. Otherwise, say N.
  1499. endif # APM
  1500. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1501. source "drivers/cpuidle/Kconfig"
  1502. source "drivers/idle/Kconfig"
  1503. endmenu
  1504. menu "Bus options (PCI etc.)"
  1505. config PCI
  1506. bool "PCI support"
  1507. default y
  1508. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1509. ---help---
  1510. Find out whether you have a PCI motherboard. PCI is the name of a
  1511. bus system, i.e. the way the CPU talks to the other stuff inside
  1512. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1513. VESA. If you have PCI, say Y, otherwise N.
  1514. choice
  1515. prompt "PCI access mode"
  1516. depends on X86_32 && PCI
  1517. default PCI_GOANY
  1518. ---help---
  1519. On PCI systems, the BIOS can be used to detect the PCI devices and
  1520. determine their configuration. However, some old PCI motherboards
  1521. have BIOS bugs and may crash if this is done. Also, some embedded
  1522. PCI-based systems don't have any BIOS at all. Linux can also try to
  1523. detect the PCI hardware directly without using the BIOS.
  1524. With this option, you can specify how Linux should detect the
  1525. PCI devices. If you choose "BIOS", the BIOS will be used,
  1526. if you choose "Direct", the BIOS won't be used, and if you
  1527. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1528. If you choose "Any", the kernel will try MMCONFIG, then the
  1529. direct access method and falls back to the BIOS if that doesn't
  1530. work. If unsure, go with the default, which is "Any".
  1531. config PCI_GOBIOS
  1532. bool "BIOS"
  1533. config PCI_GOMMCONFIG
  1534. bool "MMConfig"
  1535. config PCI_GODIRECT
  1536. bool "Direct"
  1537. config PCI_GOOLPC
  1538. bool "OLPC"
  1539. depends on OLPC
  1540. config PCI_GOANY
  1541. bool "Any"
  1542. endchoice
  1543. config PCI_BIOS
  1544. def_bool y
  1545. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1546. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1547. config PCI_DIRECT
  1548. def_bool y
  1549. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1550. config PCI_MMCONFIG
  1551. def_bool y
  1552. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1553. config PCI_OLPC
  1554. def_bool y
  1555. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1556. config PCI_DOMAINS
  1557. def_bool y
  1558. depends on PCI
  1559. config PCI_MMCONFIG
  1560. bool "Support mmconfig PCI config space access"
  1561. depends on X86_64 && PCI && ACPI
  1562. config DMAR
  1563. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1564. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1565. help
  1566. DMA remapping (DMAR) devices support enables independent address
  1567. translations for Direct Memory Access (DMA) from devices.
  1568. These DMA remapping devices are reported via ACPI tables
  1569. and include PCI device scope covered by these DMA
  1570. remapping devices.
  1571. config DMAR_DEFAULT_ON
  1572. def_bool y
  1573. prompt "Enable DMA Remapping Devices by default"
  1574. depends on DMAR
  1575. help
  1576. Selecting this option will enable a DMAR device at boot time if
  1577. one is found. If this option is not selected, DMAR support can
  1578. be enabled by passing intel_iommu=on to the kernel. It is
  1579. recommended you say N here while the DMAR code remains
  1580. experimental.
  1581. config DMAR_GFX_WA
  1582. def_bool y
  1583. prompt "Support for Graphics workaround"
  1584. depends on DMAR
  1585. ---help---
  1586. Current Graphics drivers tend to use physical address
  1587. for DMA and avoid using DMA APIs. Setting this config
  1588. option permits the IOMMU driver to set a unity map for
  1589. all the OS-visible memory. Hence the driver can continue
  1590. to use physical addresses for DMA.
  1591. config DMAR_FLOPPY_WA
  1592. def_bool y
  1593. depends on DMAR
  1594. ---help---
  1595. Floppy disk drivers are know to bypass DMA API calls
  1596. thereby failing to work when IOMMU is enabled. This
  1597. workaround will setup a 1:1 mapping for the first
  1598. 16M to make floppy (an ISA device) work.
  1599. config INTR_REMAP
  1600. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1601. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1602. ---help---
  1603. Supports Interrupt remapping for IO-APIC and MSI devices.
  1604. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1605. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1606. source "drivers/pci/pcie/Kconfig"
  1607. source "drivers/pci/Kconfig"
  1608. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1609. config ISA_DMA_API
  1610. def_bool y
  1611. if X86_32
  1612. config ISA
  1613. bool "ISA support"
  1614. ---help---
  1615. Find out whether you have ISA slots on your motherboard. ISA is the
  1616. name of a bus system, i.e. the way the CPU talks to the other stuff
  1617. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1618. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1619. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1620. config EISA
  1621. bool "EISA support"
  1622. depends on ISA
  1623. ---help---
  1624. The Extended Industry Standard Architecture (EISA) bus was
  1625. developed as an open alternative to the IBM MicroChannel bus.
  1626. The EISA bus provided some of the features of the IBM MicroChannel
  1627. bus while maintaining backward compatibility with cards made for
  1628. the older ISA bus. The EISA bus saw limited use between 1988 and
  1629. 1995 when it was made obsolete by the PCI bus.
  1630. Say Y here if you are building a kernel for an EISA-based machine.
  1631. Otherwise, say N.
  1632. source "drivers/eisa/Kconfig"
  1633. config MCA
  1634. bool "MCA support"
  1635. ---help---
  1636. MicroChannel Architecture is found in some IBM PS/2 machines and
  1637. laptops. It is a bus system similar to PCI or ISA. See
  1638. <file:Documentation/mca.txt> (and especially the web page given
  1639. there) before attempting to build an MCA bus kernel.
  1640. source "drivers/mca/Kconfig"
  1641. config SCx200
  1642. tristate "NatSemi SCx200 support"
  1643. ---help---
  1644. This provides basic support for National Semiconductor's
  1645. (now AMD's) Geode processors. The driver probes for the
  1646. PCI-IDs of several on-chip devices, so its a good dependency
  1647. for other scx200_* drivers.
  1648. If compiled as a module, the driver is named scx200.
  1649. config SCx200HR_TIMER
  1650. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1651. depends on SCx200 && GENERIC_TIME
  1652. default y
  1653. ---help---
  1654. This driver provides a clocksource built upon the on-chip
  1655. 27MHz high-resolution timer. Its also a workaround for
  1656. NSC Geode SC-1100's buggy TSC, which loses time when the
  1657. processor goes idle (as is done by the scheduler). The
  1658. other workaround is idle=poll boot option.
  1659. config GEODE_MFGPT_TIMER
  1660. def_bool y
  1661. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1662. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1663. ---help---
  1664. This driver provides a clock event source based on the MFGPT
  1665. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1666. MFGPTs have a better resolution and max interval than the
  1667. generic PIT, and are suitable for use as high-res timers.
  1668. config OLPC
  1669. bool "One Laptop Per Child support"
  1670. default n
  1671. ---help---
  1672. Add support for detecting the unique features of the OLPC
  1673. XO hardware.
  1674. endif # X86_32
  1675. config K8_NB
  1676. def_bool y
  1677. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1678. source "drivers/pcmcia/Kconfig"
  1679. source "drivers/pci/hotplug/Kconfig"
  1680. endmenu
  1681. menu "Executable file formats / Emulations"
  1682. source "fs/Kconfig.binfmt"
  1683. config IA32_EMULATION
  1684. bool "IA32 Emulation"
  1685. depends on X86_64
  1686. select COMPAT_BINFMT_ELF
  1687. ---help---
  1688. Include code to run 32-bit programs under a 64-bit kernel. You should
  1689. likely turn this on, unless you're 100% sure that you don't have any
  1690. 32-bit programs left.
  1691. config IA32_AOUT
  1692. tristate "IA32 a.out support"
  1693. depends on IA32_EMULATION
  1694. ---help---
  1695. Support old a.out binaries in the 32bit emulation.
  1696. config COMPAT
  1697. def_bool y
  1698. depends on IA32_EMULATION
  1699. config COMPAT_FOR_U64_ALIGNMENT
  1700. def_bool COMPAT
  1701. depends on X86_64
  1702. config SYSVIPC_COMPAT
  1703. def_bool y
  1704. depends on COMPAT && SYSVIPC
  1705. endmenu
  1706. config HAVE_ATOMIC_IOMAP
  1707. def_bool y
  1708. depends on X86_32
  1709. source "net/Kconfig"
  1710. source "drivers/Kconfig"
  1711. source "drivers/firmware/Kconfig"
  1712. source "fs/Kconfig"
  1713. source "arch/x86/Kconfig.debug"
  1714. source "security/Kconfig"
  1715. source "crypto/Kconfig"
  1716. source "arch/x86/kvm/Kconfig"
  1717. source "lib/Kconfig"