Kconfig 74 KB

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  1. # Select 32 or 64 bit
  2. config 64BIT
  3. bool "64-bit kernel" if ARCH = "x86"
  4. default ARCH != "i386"
  5. ---help---
  6. Say yes to build a 64-bit kernel - formerly known as x86_64
  7. Say no to build a 32-bit kernel - formerly known as i386
  8. config X86_32
  9. def_bool y
  10. depends on !64BIT
  11. select CLKSRC_I8253
  12. select HAVE_UID16
  13. config X86_64
  14. def_bool y
  15. depends on 64BIT
  16. select X86_DEV_DMA_OPS
  17. ### Arch settings
  18. config X86
  19. def_bool y
  20. select HAVE_AOUT if X86_32
  21. select HAVE_UNSTABLE_SCHED_CLOCK
  22. select ARCH_SUPPORTS_NUMA_BALANCING
  23. select ARCH_WANTS_PROT_NUMA_PROT_NONE
  24. select HAVE_IDE
  25. select HAVE_OPROFILE
  26. select HAVE_PCSPKR_PLATFORM
  27. select HAVE_PERF_EVENTS
  28. select HAVE_IOREMAP_PROT
  29. select HAVE_KPROBES
  30. select HAVE_MEMBLOCK
  31. select HAVE_MEMBLOCK_NODE_MAP
  32. select ARCH_DISCARD_MEMBLOCK
  33. select ARCH_WANT_OPTIONAL_GPIOLIB
  34. select ARCH_WANT_FRAME_POINTERS
  35. select HAVE_DMA_ATTRS
  36. select HAVE_DMA_CONTIGUOUS if !SWIOTLB
  37. select HAVE_KRETPROBES
  38. select HAVE_OPTPROBES
  39. select HAVE_KPROBES_ON_FTRACE
  40. select HAVE_FTRACE_MCOUNT_RECORD
  41. select HAVE_FENTRY if X86_64
  42. select HAVE_C_RECORDMCOUNT
  43. select HAVE_DYNAMIC_FTRACE
  44. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  45. select HAVE_FUNCTION_TRACER
  46. select HAVE_FUNCTION_GRAPH_TRACER
  47. select HAVE_FUNCTION_GRAPH_FP_TEST
  48. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  49. select HAVE_SYSCALL_TRACEPOINTS
  50. select SYSCTL_EXCEPTION_TRACE
  51. select HAVE_KVM
  52. select HAVE_ARCH_KGDB
  53. select HAVE_ARCH_TRACEHOOK
  54. select HAVE_GENERIC_DMA_COHERENT if X86_32
  55. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  56. select USER_STACKTRACE_SUPPORT
  57. select HAVE_REGS_AND_STACK_ACCESS_API
  58. select HAVE_DMA_API_DEBUG
  59. select HAVE_KERNEL_GZIP
  60. select HAVE_KERNEL_BZIP2
  61. select HAVE_KERNEL_LZMA
  62. select HAVE_KERNEL_XZ
  63. select HAVE_KERNEL_LZO
  64. select HAVE_HW_BREAKPOINT
  65. select HAVE_MIXED_BREAKPOINTS_REGS
  66. select PERF_EVENTS
  67. select HAVE_PERF_EVENTS_NMI
  68. select HAVE_PERF_REGS
  69. select HAVE_PERF_USER_STACK_DUMP
  70. select HAVE_DEBUG_KMEMLEAK
  71. select ANON_INODES
  72. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  73. select HAVE_CMPXCHG_LOCAL
  74. select HAVE_CMPXCHG_DOUBLE
  75. select HAVE_ARCH_KMEMCHECK
  76. select HAVE_USER_RETURN_NOTIFIER
  77. select ARCH_BINFMT_ELF_RANDOMIZE_PIE
  78. select HAVE_ARCH_JUMP_LABEL
  79. select HAVE_TEXT_POKE_SMP
  80. select HAVE_GENERIC_HARDIRQS
  81. select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  82. select SPARSE_IRQ
  83. select GENERIC_FIND_FIRST_BIT
  84. select GENERIC_IRQ_PROBE
  85. select GENERIC_PENDING_IRQ if SMP
  86. select GENERIC_IRQ_SHOW
  87. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  88. select IRQ_FORCED_THREADING
  89. select USE_GENERIC_SMP_HELPERS if SMP
  90. select HAVE_BPF_JIT if X86_64
  91. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  92. select CLKEVT_I8253
  93. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  94. select GENERIC_IOMAP
  95. select DCACHE_WORD_ACCESS
  96. select GENERIC_SMP_IDLE_THREAD
  97. select ARCH_WANT_IPC_PARSE_VERSION if X86_32
  98. select HAVE_ARCH_SECCOMP_FILTER
  99. select BUILDTIME_EXTABLE_SORT
  100. select GENERIC_CMOS_UPDATE
  101. select CLOCKSOURCE_WATCHDOG
  102. select GENERIC_CLOCKEVENTS
  103. select ARCH_CLOCKSOURCE_DATA if X86_64
  104. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  105. select GENERIC_TIME_VSYSCALL if X86_64
  106. select KTIME_SCALAR if X86_32
  107. select ALWAYS_USE_PERSISTENT_CLOCK
  108. select GENERIC_STRNCPY_FROM_USER
  109. select GENERIC_STRNLEN_USER
  110. select HAVE_CONTEXT_TRACKING if X86_64
  111. select HAVE_IRQ_TIME_ACCOUNTING
  112. select MODULES_USE_ELF_REL if X86_32
  113. select MODULES_USE_ELF_RELA if X86_64
  114. select CLONE_BACKWARDS if X86_32
  115. select GENERIC_SIGALTSTACK
  116. select ARCH_USE_BUILTIN_BSWAP
  117. config INSTRUCTION_DECODER
  118. def_bool y
  119. depends on KPROBES || PERF_EVENTS || UPROBES
  120. config OUTPUT_FORMAT
  121. string
  122. default "elf32-i386" if X86_32
  123. default "elf64-x86-64" if X86_64
  124. config ARCH_DEFCONFIG
  125. string
  126. default "arch/x86/configs/i386_defconfig" if X86_32
  127. default "arch/x86/configs/x86_64_defconfig" if X86_64
  128. config LOCKDEP_SUPPORT
  129. def_bool y
  130. config STACKTRACE_SUPPORT
  131. def_bool y
  132. config HAVE_LATENCYTOP_SUPPORT
  133. def_bool y
  134. config MMU
  135. def_bool y
  136. config SBUS
  137. bool
  138. config NEED_DMA_MAP_STATE
  139. def_bool y
  140. depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
  141. config NEED_SG_DMA_LENGTH
  142. def_bool y
  143. config GENERIC_ISA_DMA
  144. def_bool y
  145. depends on ISA_DMA_API
  146. config GENERIC_BUG
  147. def_bool y
  148. depends on BUG
  149. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  150. config GENERIC_BUG_RELATIVE_POINTERS
  151. bool
  152. config GENERIC_HWEIGHT
  153. def_bool y
  154. config GENERIC_GPIO
  155. bool
  156. config ARCH_MAY_HAVE_PC_FDC
  157. def_bool y
  158. depends on ISA_DMA_API
  159. config RWSEM_XCHGADD_ALGORITHM
  160. def_bool y
  161. config GENERIC_CALIBRATE_DELAY
  162. def_bool y
  163. config ARCH_HAS_CPU_RELAX
  164. def_bool y
  165. config ARCH_HAS_DEFAULT_IDLE
  166. def_bool y
  167. config ARCH_HAS_CACHE_LINE_SIZE
  168. def_bool y
  169. config ARCH_HAS_CPU_AUTOPROBE
  170. def_bool y
  171. config HAVE_SETUP_PER_CPU_AREA
  172. def_bool y
  173. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  174. def_bool y
  175. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  176. def_bool y
  177. config ARCH_HIBERNATION_POSSIBLE
  178. def_bool y
  179. config ARCH_SUSPEND_POSSIBLE
  180. def_bool y
  181. config ZONE_DMA32
  182. bool
  183. default X86_64
  184. config AUDIT_ARCH
  185. bool
  186. default X86_64
  187. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  188. def_bool y
  189. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  190. def_bool y
  191. config HAVE_INTEL_TXT
  192. def_bool y
  193. depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
  194. config X86_32_SMP
  195. def_bool y
  196. depends on X86_32 && SMP
  197. config X86_64_SMP
  198. def_bool y
  199. depends on X86_64 && SMP
  200. config X86_HT
  201. def_bool y
  202. depends on SMP
  203. config X86_32_LAZY_GS
  204. def_bool y
  205. depends on X86_32 && !CC_STACKPROTECTOR
  206. config ARCH_HWEIGHT_CFLAGS
  207. string
  208. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  209. 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
  210. config ARCH_CPU_PROBE_RELEASE
  211. def_bool y
  212. depends on HOTPLUG_CPU
  213. config ARCH_SUPPORTS_UPROBES
  214. def_bool y
  215. source "init/Kconfig"
  216. source "kernel/Kconfig.freezer"
  217. menu "Processor type and features"
  218. config ZONE_DMA
  219. bool "DMA memory allocation support" if EXPERT
  220. default y
  221. help
  222. DMA memory allocation support allows devices with less than 32-bit
  223. addressing to allocate within the first 16MB of address space.
  224. Disable if no such devices will be used.
  225. If unsure, say Y.
  226. config SMP
  227. bool "Symmetric multi-processing support"
  228. ---help---
  229. This enables support for systems with more than one CPU. If you have
  230. a system with only one CPU, like most personal computers, say N. If
  231. you have a system with more than one CPU, say Y.
  232. If you say N here, the kernel will run on single and multiprocessor
  233. machines, but will use only one CPU of a multiprocessor machine. If
  234. you say Y here, the kernel will run on many, but not all,
  235. singleprocessor machines. On a singleprocessor machine, the kernel
  236. will run faster if you say N here.
  237. Note that if you say Y here and choose architecture "586" or
  238. "Pentium" under "Processor family", the kernel will not work on 486
  239. architectures. Similarly, multiprocessor kernels for the "PPro"
  240. architecture may not work on all Pentium based boards.
  241. People using multiprocessor machines who say Y here should also say
  242. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  243. Management" code will be disabled if you say Y here.
  244. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  245. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  246. <http://www.tldp.org/docs.html#howto>.
  247. If you don't know what to do here, say N.
  248. config X86_X2APIC
  249. bool "Support x2apic"
  250. depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
  251. ---help---
  252. This enables x2apic support on CPUs that have this feature.
  253. This allows 32-bit apic IDs (so it can support very large systems),
  254. and accesses the local apic via MSRs not via mmio.
  255. If you don't know what to do here, say N.
  256. config X86_MPPARSE
  257. bool "Enable MPS table" if ACPI || SFI
  258. default y
  259. depends on X86_LOCAL_APIC
  260. ---help---
  261. For old smp systems that do not have proper acpi support. Newer systems
  262. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  263. config X86_BIGSMP
  264. bool "Support for big SMP systems with more than 8 CPUs"
  265. depends on X86_32 && SMP
  266. ---help---
  267. This option is needed for the systems that have more than 8 CPUs
  268. config GOLDFISH
  269. def_bool y
  270. depends on X86_GOLDFISH
  271. if X86_32
  272. config X86_EXTENDED_PLATFORM
  273. bool "Support for extended (non-PC) x86 platforms"
  274. default y
  275. ---help---
  276. If you disable this option then the kernel will only support
  277. standard PC platforms. (which covers the vast majority of
  278. systems out there.)
  279. If you enable this option then you'll be able to select support
  280. for the following (non-PC) 32 bit x86 platforms:
  281. AMD Elan
  282. NUMAQ (IBM/Sequent)
  283. RDC R-321x SoC
  284. SGI 320/540 (Visual Workstation)
  285. STA2X11-based (e.g. Northville)
  286. Summit/EXA (IBM x440)
  287. Unisys ES7000 IA32 series
  288. Moorestown MID devices
  289. If you have one of these systems, or if you want to build a
  290. generic distribution kernel, say Y here - otherwise say N.
  291. endif
  292. if X86_64
  293. config X86_EXTENDED_PLATFORM
  294. bool "Support for extended (non-PC) x86 platforms"
  295. default y
  296. ---help---
  297. If you disable this option then the kernel will only support
  298. standard PC platforms. (which covers the vast majority of
  299. systems out there.)
  300. If you enable this option then you'll be able to select support
  301. for the following (non-PC) 64 bit x86 platforms:
  302. Numascale NumaChip
  303. ScaleMP vSMP
  304. SGI Ultraviolet
  305. If you have one of these systems, or if you want to build a
  306. generic distribution kernel, say Y here - otherwise say N.
  307. endif
  308. # This is an alphabetically sorted list of 64 bit extended platforms
  309. # Please maintain the alphabetic order if and when there are additions
  310. config X86_NUMACHIP
  311. bool "Numascale NumaChip"
  312. depends on X86_64
  313. depends on X86_EXTENDED_PLATFORM
  314. depends on NUMA
  315. depends on SMP
  316. depends on X86_X2APIC
  317. depends on PCI_MMCONFIG
  318. ---help---
  319. Adds support for Numascale NumaChip large-SMP systems. Needed to
  320. enable more than ~168 cores.
  321. If you don't have one of these, you should say N here.
  322. config X86_VSMP
  323. bool "ScaleMP vSMP"
  324. select PARAVIRT_GUEST
  325. select PARAVIRT
  326. depends on X86_64 && PCI
  327. depends on X86_EXTENDED_PLATFORM
  328. depends on SMP
  329. ---help---
  330. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  331. supposed to run on these EM64T-based machines. Only choose this option
  332. if you have one of these machines.
  333. config X86_UV
  334. bool "SGI Ultraviolet"
  335. depends on X86_64
  336. depends on X86_EXTENDED_PLATFORM
  337. depends on NUMA
  338. depends on X86_X2APIC
  339. ---help---
  340. This option is needed in order to support SGI Ultraviolet systems.
  341. If you don't have one of these, you should say N here.
  342. # Following is an alphabetically sorted list of 32 bit extended platforms
  343. # Please maintain the alphabetic order if and when there are additions
  344. config X86_GOLDFISH
  345. bool "Goldfish (Virtual Platform)"
  346. depends on X86_32
  347. ---help---
  348. Enable support for the Goldfish virtual platform used primarily
  349. for Android development. Unless you are building for the Android
  350. Goldfish emulator say N here.
  351. config X86_INTEL_CE
  352. bool "CE4100 TV platform"
  353. depends on PCI
  354. depends on PCI_GODIRECT
  355. depends on X86_32
  356. depends on X86_EXTENDED_PLATFORM
  357. select X86_REBOOTFIXUPS
  358. select OF
  359. select OF_EARLY_FLATTREE
  360. select IRQ_DOMAIN
  361. ---help---
  362. Select for the Intel CE media processor (CE4100) SOC.
  363. This option compiles in support for the CE4100 SOC for settop
  364. boxes and media devices.
  365. config X86_WANT_INTEL_MID
  366. bool "Intel MID platform support"
  367. depends on X86_32
  368. depends on X86_EXTENDED_PLATFORM
  369. ---help---
  370. Select to build a kernel capable of supporting Intel MID platform
  371. systems which do not have the PCI legacy interfaces (Moorestown,
  372. Medfield). If you are building for a PC class system say N here.
  373. if X86_WANT_INTEL_MID
  374. config X86_INTEL_MID
  375. bool
  376. config X86_MDFLD
  377. bool "Medfield MID platform"
  378. depends on PCI
  379. depends on PCI_GOANY
  380. depends on X86_IO_APIC
  381. select X86_INTEL_MID
  382. select SFI
  383. select DW_APB_TIMER
  384. select APB_TIMER
  385. select I2C
  386. select SPI
  387. select INTEL_SCU_IPC
  388. select X86_PLATFORM_DEVICES
  389. select MFD_INTEL_MSIC
  390. ---help---
  391. Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
  392. Internet Device(MID) platform.
  393. Unlike standard x86 PCs, Medfield does not have many legacy devices
  394. nor standard legacy replacement devices/features. e.g. Medfield does
  395. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  396. endif
  397. config X86_INTEL_LPSS
  398. bool "Intel Low Power Subsystem Support"
  399. depends on ACPI
  400. select COMMON_CLK
  401. ---help---
  402. Select to build support for Intel Low Power Subsystem such as
  403. found on Intel Lynxpoint PCH. Selecting this option enables
  404. things like clock tree (common clock framework) which are needed
  405. by the LPSS peripheral drivers.
  406. config X86_RDC321X
  407. bool "RDC R-321x SoC"
  408. depends on X86_32
  409. depends on X86_EXTENDED_PLATFORM
  410. select M486
  411. select X86_REBOOTFIXUPS
  412. ---help---
  413. This option is needed for RDC R-321x system-on-chip, also known
  414. as R-8610-(G).
  415. If you don't have one of these chips, you should say N here.
  416. config X86_32_NON_STANDARD
  417. bool "Support non-standard 32-bit SMP architectures"
  418. depends on X86_32 && SMP
  419. depends on X86_EXTENDED_PLATFORM
  420. ---help---
  421. This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
  422. STA2X11, default subarchitectures. It is intended for a generic
  423. binary kernel. If you select them all, kernel will probe it
  424. one by one and will fallback to default.
  425. # Alphabetically sorted list of Non standard 32 bit platforms
  426. config X86_NUMAQ
  427. bool "NUMAQ (IBM/Sequent)"
  428. depends on X86_32_NON_STANDARD
  429. depends on PCI
  430. select NUMA
  431. select X86_MPPARSE
  432. ---help---
  433. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  434. NUMA multiquad box. This changes the way that processors are
  435. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  436. of Flat Logical. You will need a new lynxer.elf file to flash your
  437. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  438. config X86_SUPPORTS_MEMORY_FAILURE
  439. def_bool y
  440. # MCE code calls memory_failure():
  441. depends on X86_MCE
  442. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  443. depends on !X86_NUMAQ
  444. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  445. depends on X86_64 || !SPARSEMEM
  446. select ARCH_SUPPORTS_MEMORY_FAILURE
  447. config X86_VISWS
  448. bool "SGI 320/540 (Visual Workstation)"
  449. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  450. depends on X86_32_NON_STANDARD
  451. ---help---
  452. The SGI Visual Workstation series is an IA32-based workstation
  453. based on SGI systems chips with some legacy PC hardware attached.
  454. Say Y here to create a kernel to run on the SGI 320 or 540.
  455. A kernel compiled for the Visual Workstation will run on general
  456. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  457. config STA2X11
  458. bool "STA2X11 Companion Chip Support"
  459. depends on X86_32_NON_STANDARD && PCI
  460. select X86_DEV_DMA_OPS
  461. select X86_DMA_REMAP
  462. select SWIOTLB
  463. select MFD_STA2X11
  464. select ARCH_REQUIRE_GPIOLIB
  465. default n
  466. ---help---
  467. This adds support for boards based on the STA2X11 IO-Hub,
  468. a.k.a. "ConneXt". The chip is used in place of the standard
  469. PC chipset, so all "standard" peripherals are missing. If this
  470. option is selected the kernel will still be able to boot on
  471. standard PC machines.
  472. config X86_SUMMIT
  473. bool "Summit/EXA (IBM x440)"
  474. depends on X86_32_NON_STANDARD
  475. ---help---
  476. This option is needed for IBM systems that use the Summit/EXA chipset.
  477. In particular, it is needed for the x440.
  478. config X86_ES7000
  479. bool "Unisys ES7000 IA32 series"
  480. depends on X86_32_NON_STANDARD && X86_BIGSMP
  481. ---help---
  482. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  483. supposed to run on an IA32-based Unisys ES7000 system.
  484. config X86_32_IRIS
  485. tristate "Eurobraille/Iris poweroff module"
  486. depends on X86_32
  487. ---help---
  488. The Iris machines from EuroBraille do not have APM or ACPI support
  489. to shut themselves down properly. A special I/O sequence is
  490. needed to do so, which is what this module does at
  491. kernel shutdown.
  492. This is only for Iris machines from EuroBraille.
  493. If unused, say N.
  494. config SCHED_OMIT_FRAME_POINTER
  495. def_bool y
  496. prompt "Single-depth WCHAN output"
  497. depends on X86
  498. ---help---
  499. Calculate simpler /proc/<PID>/wchan values. If this option
  500. is disabled then wchan values will recurse back to the
  501. caller function. This provides more accurate wchan values,
  502. at the expense of slightly more scheduling overhead.
  503. If in doubt, say "Y".
  504. menuconfig PARAVIRT_GUEST
  505. bool "Paravirtualized guest support"
  506. ---help---
  507. Say Y here to get to see options related to running Linux under
  508. various hypervisors. This option alone does not add any kernel code.
  509. If you say N, all options in this submenu will be skipped and disabled.
  510. if PARAVIRT_GUEST
  511. config PARAVIRT_TIME_ACCOUNTING
  512. bool "Paravirtual steal time accounting"
  513. select PARAVIRT
  514. default n
  515. ---help---
  516. Select this option to enable fine granularity task steal time
  517. accounting. Time spent executing other tasks in parallel with
  518. the current vCPU is discounted from the vCPU power. To account for
  519. that, there can be a small performance impact.
  520. If in doubt, say N here.
  521. source "arch/x86/xen/Kconfig"
  522. config KVM_GUEST
  523. bool "KVM Guest support (including kvmclock)"
  524. select PARAVIRT
  525. select PARAVIRT
  526. select PARAVIRT_CLOCK
  527. default y if PARAVIRT_GUEST
  528. ---help---
  529. This option enables various optimizations for running under the KVM
  530. hypervisor. It includes a paravirtualized clock, so that instead
  531. of relying on a PIT (or probably other) emulation by the
  532. underlying device model, the host provides the guest with
  533. timing infrastructure such as time of day, and system time
  534. source "arch/x86/lguest/Kconfig"
  535. config PARAVIRT
  536. bool "Enable paravirtualization code"
  537. ---help---
  538. This changes the kernel so it can modify itself when it is run
  539. under a hypervisor, potentially improving performance significantly
  540. over full virtualization. However, when run without a hypervisor
  541. the kernel is theoretically slower and slightly larger.
  542. config PARAVIRT_SPINLOCKS
  543. bool "Paravirtualization layer for spinlocks"
  544. depends on PARAVIRT && SMP && EXPERIMENTAL
  545. ---help---
  546. Paravirtualized spinlocks allow a pvops backend to replace the
  547. spinlock implementation with something virtualization-friendly
  548. (for example, block the virtual CPU rather than spinning).
  549. Unfortunately the downside is an up to 5% performance hit on
  550. native kernels, with various workloads.
  551. If you are unsure how to answer this question, answer N.
  552. config PARAVIRT_CLOCK
  553. bool
  554. endif
  555. config PARAVIRT_DEBUG
  556. bool "paravirt-ops debugging"
  557. depends on PARAVIRT && DEBUG_KERNEL
  558. ---help---
  559. Enable to debug paravirt_ops internals. Specifically, BUG if
  560. a paravirt_op is missing when it is called.
  561. config NO_BOOTMEM
  562. def_bool y
  563. config MEMTEST
  564. bool "Memtest"
  565. ---help---
  566. This option adds a kernel parameter 'memtest', which allows memtest
  567. to be set.
  568. memtest=0, mean disabled; -- default
  569. memtest=1, mean do 1 test pattern;
  570. ...
  571. memtest=4, mean do 4 test patterns.
  572. If you are unsure how to answer this question, answer N.
  573. config X86_SUMMIT_NUMA
  574. def_bool y
  575. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  576. config X86_CYCLONE_TIMER
  577. def_bool y
  578. depends on X86_SUMMIT
  579. source "arch/x86/Kconfig.cpu"
  580. config HPET_TIMER
  581. def_bool X86_64
  582. prompt "HPET Timer Support" if X86_32
  583. ---help---
  584. Use the IA-PC HPET (High Precision Event Timer) to manage
  585. time in preference to the PIT and RTC, if a HPET is
  586. present.
  587. HPET is the next generation timer replacing legacy 8254s.
  588. The HPET provides a stable time base on SMP
  589. systems, unlike the TSC, but it is more expensive to access,
  590. as it is off-chip. You can find the HPET spec at
  591. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  592. You can safely choose Y here. However, HPET will only be
  593. activated if the platform and the BIOS support this feature.
  594. Otherwise the 8254 will be used for timing services.
  595. Choose N to continue using the legacy 8254 timer.
  596. config HPET_EMULATE_RTC
  597. def_bool y
  598. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  599. config APB_TIMER
  600. def_bool y if X86_INTEL_MID
  601. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  602. select DW_APB_TIMER
  603. depends on X86_INTEL_MID && SFI
  604. help
  605. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  606. The APBT provides a stable time base on SMP
  607. systems, unlike the TSC, but it is more expensive to access,
  608. as it is off-chip. APB timers are always running regardless of CPU
  609. C states, they are used as per CPU clockevent device when possible.
  610. # Mark as expert because too many people got it wrong.
  611. # The code disables itself when not needed.
  612. config DMI
  613. default y
  614. bool "Enable DMI scanning" if EXPERT
  615. ---help---
  616. Enabled scanning of DMI to identify machine quirks. Say Y
  617. here unless you have verified that your setup is not
  618. affected by entries in the DMI blacklist. Required by PNP
  619. BIOS code.
  620. config GART_IOMMU
  621. bool "GART IOMMU support" if EXPERT
  622. default y
  623. select SWIOTLB
  624. depends on X86_64 && PCI && AMD_NB
  625. ---help---
  626. Support for full DMA access of devices with 32bit memory access only
  627. on systems with more than 3GB. This is usually needed for USB,
  628. sound, many IDE/SATA chipsets and some other devices.
  629. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  630. based hardware IOMMU and a software bounce buffer based IOMMU used
  631. on Intel systems and as fallback.
  632. The code is only active when needed (enough memory and limited
  633. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  634. too.
  635. config CALGARY_IOMMU
  636. bool "IBM Calgary IOMMU support"
  637. select SWIOTLB
  638. depends on X86_64 && PCI && EXPERIMENTAL
  639. ---help---
  640. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  641. systems. Needed to run systems with more than 3GB of memory
  642. properly with 32-bit PCI devices that do not support DAC
  643. (Double Address Cycle). Calgary also supports bus level
  644. isolation, where all DMAs pass through the IOMMU. This
  645. prevents them from going anywhere except their intended
  646. destination. This catches hard-to-find kernel bugs and
  647. mis-behaving drivers and devices that do not use the DMA-API
  648. properly to set up their DMA buffers. The IOMMU can be
  649. turned off at boot time with the iommu=off parameter.
  650. Normally the kernel will make the right choice by itself.
  651. If unsure, say Y.
  652. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  653. def_bool y
  654. prompt "Should Calgary be enabled by default?"
  655. depends on CALGARY_IOMMU
  656. ---help---
  657. Should Calgary be enabled by default? if you choose 'y', Calgary
  658. will be used (if it exists). If you choose 'n', Calgary will not be
  659. used even if it exists. If you choose 'n' and would like to use
  660. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  661. If unsure, say Y.
  662. # need this always selected by IOMMU for the VIA workaround
  663. config SWIOTLB
  664. def_bool y if X86_64
  665. ---help---
  666. Support for software bounce buffers used on x86-64 systems
  667. which don't have a hardware IOMMU. Using this PCI devices
  668. which can only access 32-bits of memory can be used on systems
  669. with more than 3 GB of memory.
  670. If unsure, say Y.
  671. config IOMMU_HELPER
  672. def_bool y
  673. depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
  674. config MAXSMP
  675. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  676. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  677. select CPUMASK_OFFSTACK
  678. ---help---
  679. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  680. If unsure, say N.
  681. config NR_CPUS
  682. int "Maximum number of CPUs" if SMP && !MAXSMP
  683. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  684. range 2 512 if SMP && !MAXSMP
  685. default "1" if !SMP
  686. default "4096" if MAXSMP
  687. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  688. default "8" if SMP
  689. ---help---
  690. This allows you to specify the maximum number of CPUs which this
  691. kernel will support. The maximum supported value is 512 and the
  692. minimum value which makes sense is 2.
  693. This is purely to save memory - each supported CPU adds
  694. approximately eight kilobytes to the kernel image.
  695. config SCHED_SMT
  696. bool "SMT (Hyperthreading) scheduler support"
  697. depends on X86_HT
  698. ---help---
  699. SMT scheduler support improves the CPU scheduler's decision making
  700. when dealing with Intel Pentium 4 chips with HyperThreading at a
  701. cost of slightly increased overhead in some places. If unsure say
  702. N here.
  703. config SCHED_MC
  704. def_bool y
  705. prompt "Multi-core scheduler support"
  706. depends on X86_HT
  707. ---help---
  708. Multi-core scheduler support improves the CPU scheduler's decision
  709. making when dealing with multi-core CPU chips at a cost of slightly
  710. increased overhead in some places. If unsure say N here.
  711. source "kernel/Kconfig.preempt"
  712. config X86_UP_APIC
  713. bool "Local APIC support on uniprocessors"
  714. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  715. ---help---
  716. A local APIC (Advanced Programmable Interrupt Controller) is an
  717. integrated interrupt controller in the CPU. If you have a single-CPU
  718. system which has a processor with a local APIC, you can say Y here to
  719. enable and use it. If you say Y here even though your machine doesn't
  720. have a local APIC, then the kernel will still run with no slowdown at
  721. all. The local APIC supports CPU-generated self-interrupts (timer,
  722. performance counters), and the NMI watchdog which detects hard
  723. lockups.
  724. config X86_UP_IOAPIC
  725. bool "IO-APIC support on uniprocessors"
  726. depends on X86_UP_APIC
  727. ---help---
  728. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  729. SMP-capable replacement for PC-style interrupt controllers. Most
  730. SMP systems and many recent uniprocessor systems have one.
  731. If you have a single-CPU system with an IO-APIC, you can say Y here
  732. to use it. If you say Y here even though your machine doesn't have
  733. an IO-APIC, then the kernel will still run with no slowdown at all.
  734. config X86_LOCAL_APIC
  735. def_bool y
  736. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  737. config X86_IO_APIC
  738. def_bool y
  739. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
  740. config X86_VISWS_APIC
  741. def_bool y
  742. depends on X86_32 && X86_VISWS
  743. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  744. bool "Reroute for broken boot IRQs"
  745. depends on X86_IO_APIC
  746. ---help---
  747. This option enables a workaround that fixes a source of
  748. spurious interrupts. This is recommended when threaded
  749. interrupt handling is used on systems where the generation of
  750. superfluous "boot interrupts" cannot be disabled.
  751. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  752. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  753. kernel does during interrupt handling). On chipsets where this
  754. boot IRQ generation cannot be disabled, this workaround keeps
  755. the original IRQ line masked so that only the equivalent "boot
  756. IRQ" is delivered to the CPUs. The workaround also tells the
  757. kernel to set up the IRQ handler on the boot IRQ line. In this
  758. way only one interrupt is delivered to the kernel. Otherwise
  759. the spurious second interrupt may cause the kernel to bring
  760. down (vital) interrupt lines.
  761. Only affects "broken" chipsets. Interrupt sharing may be
  762. increased on these systems.
  763. config X86_MCE
  764. bool "Machine Check / overheating reporting"
  765. default y
  766. ---help---
  767. Machine Check support allows the processor to notify the
  768. kernel if it detects a problem (e.g. overheating, data corruption).
  769. The action the kernel takes depends on the severity of the problem,
  770. ranging from warning messages to halting the machine.
  771. config X86_MCE_INTEL
  772. def_bool y
  773. prompt "Intel MCE features"
  774. depends on X86_MCE && X86_LOCAL_APIC
  775. ---help---
  776. Additional support for intel specific MCE features such as
  777. the thermal monitor.
  778. config X86_MCE_AMD
  779. def_bool y
  780. prompt "AMD MCE features"
  781. depends on X86_MCE && X86_LOCAL_APIC
  782. ---help---
  783. Additional support for AMD specific MCE features such as
  784. the DRAM Error Threshold.
  785. config X86_ANCIENT_MCE
  786. bool "Support for old Pentium 5 / WinChip machine checks"
  787. depends on X86_32 && X86_MCE
  788. ---help---
  789. Include support for machine check handling on old Pentium 5 or WinChip
  790. systems. These typically need to be enabled explicitely on the command
  791. line.
  792. config X86_MCE_THRESHOLD
  793. depends on X86_MCE_AMD || X86_MCE_INTEL
  794. def_bool y
  795. config X86_MCE_INJECT
  796. depends on X86_MCE
  797. tristate "Machine check injector support"
  798. ---help---
  799. Provide support for injecting machine checks for testing purposes.
  800. If you don't know what a machine check is and you don't do kernel
  801. QA it is safe to say n.
  802. config X86_THERMAL_VECTOR
  803. def_bool y
  804. depends on X86_MCE_INTEL
  805. config VM86
  806. bool "Enable VM86 support" if EXPERT
  807. default y
  808. depends on X86_32
  809. ---help---
  810. This option is required by programs like DOSEMU to run 16-bit legacy
  811. code on X86 processors. It also may be needed by software like
  812. XFree86 to initialize some video cards via BIOS. Disabling this
  813. option saves about 6k.
  814. config TOSHIBA
  815. tristate "Toshiba Laptop support"
  816. depends on X86_32
  817. ---help---
  818. This adds a driver to safely access the System Management Mode of
  819. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  820. not work on models with a Phoenix BIOS. The System Management Mode
  821. is used to set the BIOS and power saving options on Toshiba portables.
  822. For information on utilities to make use of this driver see the
  823. Toshiba Linux utilities web site at:
  824. <http://www.buzzard.org.uk/toshiba/>.
  825. Say Y if you intend to run this kernel on a Toshiba portable.
  826. Say N otherwise.
  827. config I8K
  828. tristate "Dell laptop support"
  829. select HWMON
  830. ---help---
  831. This adds a driver to safely access the System Management Mode
  832. of the CPU on the Dell Inspiron 8000. The System Management Mode
  833. is used to read cpu temperature and cooling fan status and to
  834. control the fans on the I8K portables.
  835. This driver has been tested only on the Inspiron 8000 but it may
  836. also work with other Dell laptops. You can force loading on other
  837. models by passing the parameter `force=1' to the module. Use at
  838. your own risk.
  839. For information on utilities to make use of this driver see the
  840. I8K Linux utilities web site at:
  841. <http://people.debian.org/~dz/i8k/>
  842. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  843. Say N otherwise.
  844. config X86_REBOOTFIXUPS
  845. bool "Enable X86 board specific fixups for reboot"
  846. depends on X86_32
  847. ---help---
  848. This enables chipset and/or board specific fixups to be done
  849. in order to get reboot to work correctly. This is only needed on
  850. some combinations of hardware and BIOS. The symptom, for which
  851. this config is intended, is when reboot ends with a stalled/hung
  852. system.
  853. Currently, the only fixup is for the Geode machines using
  854. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  855. Say Y if you want to enable the fixup. Currently, it's safe to
  856. enable this option even if you don't need it.
  857. Say N otherwise.
  858. config MICROCODE
  859. tristate "CPU microcode loading support"
  860. select FW_LOADER
  861. ---help---
  862. If you say Y here, you will be able to update the microcode on
  863. certain Intel and AMD processors. The Intel support is for the
  864. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
  865. Xeon etc. The AMD support is for families 0x10 and later. You will
  866. obviously need the actual microcode binary data itself which is not
  867. shipped with the Linux kernel.
  868. This option selects the general module only, you need to select
  869. at least one vendor specific module as well.
  870. To compile this driver as a module, choose M here: the module
  871. will be called microcode.
  872. config MICROCODE_INTEL
  873. bool "Intel microcode loading support"
  874. depends on MICROCODE
  875. default MICROCODE
  876. select FW_LOADER
  877. ---help---
  878. This options enables microcode patch loading support for Intel
  879. processors.
  880. For latest news and information on obtaining all the required
  881. Intel ingredients for this driver, check:
  882. <http://www.urbanmyth.org/microcode/>.
  883. config MICROCODE_AMD
  884. bool "AMD microcode loading support"
  885. depends on MICROCODE
  886. select FW_LOADER
  887. ---help---
  888. If you select this option, microcode patch loading support for AMD
  889. processors will be enabled.
  890. config MICROCODE_OLD_INTERFACE
  891. def_bool y
  892. depends on MICROCODE
  893. config X86_MSR
  894. tristate "/dev/cpu/*/msr - Model-specific register support"
  895. ---help---
  896. This device gives privileged processes access to the x86
  897. Model-Specific Registers (MSRs). It is a character device with
  898. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  899. MSR accesses are directed to a specific CPU on multi-processor
  900. systems.
  901. config X86_CPUID
  902. tristate "/dev/cpu/*/cpuid - CPU information support"
  903. ---help---
  904. This device gives processes access to the x86 CPUID instruction to
  905. be executed on a specific processor. It is a character device
  906. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  907. /dev/cpu/31/cpuid.
  908. choice
  909. prompt "High Memory Support"
  910. default HIGHMEM64G if X86_NUMAQ
  911. default HIGHMEM4G
  912. depends on X86_32
  913. config NOHIGHMEM
  914. bool "off"
  915. depends on !X86_NUMAQ
  916. ---help---
  917. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  918. However, the address space of 32-bit x86 processors is only 4
  919. Gigabytes large. That means that, if you have a large amount of
  920. physical memory, not all of it can be "permanently mapped" by the
  921. kernel. The physical memory that's not permanently mapped is called
  922. "high memory".
  923. If you are compiling a kernel which will never run on a machine with
  924. more than 1 Gigabyte total physical RAM, answer "off" here (default
  925. choice and suitable for most users). This will result in a "3GB/1GB"
  926. split: 3GB are mapped so that each process sees a 3GB virtual memory
  927. space and the remaining part of the 4GB virtual memory space is used
  928. by the kernel to permanently map as much physical memory as
  929. possible.
  930. If the machine has between 1 and 4 Gigabytes physical RAM, then
  931. answer "4GB" here.
  932. If more than 4 Gigabytes is used then answer "64GB" here. This
  933. selection turns Intel PAE (Physical Address Extension) mode on.
  934. PAE implements 3-level paging on IA32 processors. PAE is fully
  935. supported by Linux, PAE mode is implemented on all recent Intel
  936. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  937. then the kernel will not boot on CPUs that don't support PAE!
  938. The actual amount of total physical memory will either be
  939. auto detected or can be forced by using a kernel command line option
  940. such as "mem=256M". (Try "man bootparam" or see the documentation of
  941. your boot loader (lilo or loadlin) about how to pass options to the
  942. kernel at boot time.)
  943. If unsure, say "off".
  944. config HIGHMEM4G
  945. bool "4GB"
  946. depends on !X86_NUMAQ
  947. ---help---
  948. Select this if you have a 32-bit processor and between 1 and 4
  949. gigabytes of physical RAM.
  950. config HIGHMEM64G
  951. bool "64GB"
  952. depends on !M486
  953. select X86_PAE
  954. ---help---
  955. Select this if you have a 32-bit processor and more than 4
  956. gigabytes of physical RAM.
  957. endchoice
  958. choice
  959. depends on EXPERIMENTAL
  960. prompt "Memory split" if EXPERT
  961. default VMSPLIT_3G
  962. depends on X86_32
  963. ---help---
  964. Select the desired split between kernel and user memory.
  965. If the address range available to the kernel is less than the
  966. physical memory installed, the remaining memory will be available
  967. as "high memory". Accessing high memory is a little more costly
  968. than low memory, as it needs to be mapped into the kernel first.
  969. Note that increasing the kernel address space limits the range
  970. available to user programs, making the address space there
  971. tighter. Selecting anything other than the default 3G/1G split
  972. will also likely make your kernel incompatible with binary-only
  973. kernel modules.
  974. If you are not absolutely sure what you are doing, leave this
  975. option alone!
  976. config VMSPLIT_3G
  977. bool "3G/1G user/kernel split"
  978. config VMSPLIT_3G_OPT
  979. depends on !X86_PAE
  980. bool "3G/1G user/kernel split (for full 1G low memory)"
  981. config VMSPLIT_2G
  982. bool "2G/2G user/kernel split"
  983. config VMSPLIT_2G_OPT
  984. depends on !X86_PAE
  985. bool "2G/2G user/kernel split (for full 2G low memory)"
  986. config VMSPLIT_1G
  987. bool "1G/3G user/kernel split"
  988. endchoice
  989. config PAGE_OFFSET
  990. hex
  991. default 0xB0000000 if VMSPLIT_3G_OPT
  992. default 0x80000000 if VMSPLIT_2G
  993. default 0x78000000 if VMSPLIT_2G_OPT
  994. default 0x40000000 if VMSPLIT_1G
  995. default 0xC0000000
  996. depends on X86_32
  997. config HIGHMEM
  998. def_bool y
  999. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1000. config X86_PAE
  1001. bool "PAE (Physical Address Extension) Support"
  1002. depends on X86_32 && !HIGHMEM4G
  1003. ---help---
  1004. PAE is required for NX support, and furthermore enables
  1005. larger swapspace support for non-overcommit purposes. It
  1006. has the cost of more pagetable lookup overhead, and also
  1007. consumes more pagetable space per process.
  1008. config ARCH_PHYS_ADDR_T_64BIT
  1009. def_bool y
  1010. depends on X86_64 || X86_PAE
  1011. config ARCH_DMA_ADDR_T_64BIT
  1012. def_bool y
  1013. depends on X86_64 || HIGHMEM64G
  1014. config DIRECT_GBPAGES
  1015. bool "Enable 1GB pages for kernel pagetables" if EXPERT
  1016. default y
  1017. depends on X86_64
  1018. ---help---
  1019. Allow the kernel linear mapping to use 1GB pages on CPUs that
  1020. support it. This can improve the kernel's performance a tiny bit by
  1021. reducing TLB pressure. If in doubt, say "Y".
  1022. # Common NUMA Features
  1023. config NUMA
  1024. bool "Numa Memory Allocation and Scheduler Support"
  1025. depends on SMP
  1026. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  1027. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  1028. ---help---
  1029. Enable NUMA (Non Uniform Memory Access) support.
  1030. The kernel will try to allocate memory used by a CPU on the
  1031. local memory controller of the CPU and add some more
  1032. NUMA awareness to the kernel.
  1033. For 64-bit this is recommended if the system is Intel Core i7
  1034. (or later), AMD Opteron, or EM64T NUMA.
  1035. For 32-bit this is only needed on (rare) 32-bit-only platforms
  1036. that support NUMA topologies, such as NUMAQ / Summit, or if you
  1037. boot a 32-bit kernel on a 64-bit NUMA platform.
  1038. Otherwise, you should say N.
  1039. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  1040. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  1041. config AMD_NUMA
  1042. def_bool y
  1043. prompt "Old style AMD Opteron NUMA detection"
  1044. depends on X86_64 && NUMA && PCI
  1045. ---help---
  1046. Enable AMD NUMA node topology detection. You should say Y here if
  1047. you have a multi processor AMD system. This uses an old method to
  1048. read the NUMA configuration directly from the builtin Northbridge
  1049. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1050. which also takes priority if both are compiled in.
  1051. config X86_64_ACPI_NUMA
  1052. def_bool y
  1053. prompt "ACPI NUMA detection"
  1054. depends on X86_64 && NUMA && ACPI && PCI
  1055. select ACPI_NUMA
  1056. ---help---
  1057. Enable ACPI SRAT based node topology detection.
  1058. # Some NUMA nodes have memory ranges that span
  1059. # other nodes. Even though a pfn is valid and
  1060. # between a node's start and end pfns, it may not
  1061. # reside on that node. See memmap_init_zone()
  1062. # for details.
  1063. config NODES_SPAN_OTHER_NODES
  1064. def_bool y
  1065. depends on X86_64_ACPI_NUMA
  1066. config NUMA_EMU
  1067. bool "NUMA emulation"
  1068. depends on NUMA
  1069. ---help---
  1070. Enable NUMA emulation. A flat machine will be split
  1071. into virtual nodes when booted with "numa=fake=N", where N is the
  1072. number of nodes. This is only useful for debugging.
  1073. config NODES_SHIFT
  1074. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1075. range 1 10
  1076. default "10" if MAXSMP
  1077. default "6" if X86_64
  1078. default "4" if X86_NUMAQ
  1079. default "3"
  1080. depends on NEED_MULTIPLE_NODES
  1081. ---help---
  1082. Specify the maximum number of NUMA Nodes available on the target
  1083. system. Increases memory reserved to accommodate various tables.
  1084. config HAVE_ARCH_ALLOC_REMAP
  1085. def_bool y
  1086. depends on X86_32 && NUMA
  1087. config ARCH_HAVE_MEMORY_PRESENT
  1088. def_bool y
  1089. depends on X86_32 && DISCONTIGMEM
  1090. config NEED_NODE_MEMMAP_SIZE
  1091. def_bool y
  1092. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1093. config ARCH_FLATMEM_ENABLE
  1094. def_bool y
  1095. depends on X86_32 && !NUMA
  1096. config ARCH_DISCONTIGMEM_ENABLE
  1097. def_bool y
  1098. depends on NUMA && X86_32
  1099. config ARCH_DISCONTIGMEM_DEFAULT
  1100. def_bool y
  1101. depends on NUMA && X86_32
  1102. config ARCH_SPARSEMEM_ENABLE
  1103. def_bool y
  1104. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1105. select SPARSEMEM_STATIC if X86_32
  1106. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1107. config ARCH_SPARSEMEM_DEFAULT
  1108. def_bool y
  1109. depends on X86_64
  1110. config ARCH_SELECT_MEMORY_MODEL
  1111. def_bool y
  1112. depends on ARCH_SPARSEMEM_ENABLE
  1113. config ARCH_MEMORY_PROBE
  1114. def_bool y
  1115. depends on X86_64 && MEMORY_HOTPLUG
  1116. config ARCH_PROC_KCORE_TEXT
  1117. def_bool y
  1118. depends on X86_64 && PROC_KCORE
  1119. config ILLEGAL_POINTER_VALUE
  1120. hex
  1121. default 0 if X86_32
  1122. default 0xdead000000000000 if X86_64
  1123. source "mm/Kconfig"
  1124. config HIGHPTE
  1125. bool "Allocate 3rd-level pagetables from highmem"
  1126. depends on HIGHMEM
  1127. ---help---
  1128. The VM uses one page table entry for each page of physical memory.
  1129. For systems with a lot of RAM, this can be wasteful of precious
  1130. low memory. Setting this option will put user-space page table
  1131. entries in high memory.
  1132. config X86_CHECK_BIOS_CORRUPTION
  1133. bool "Check for low memory corruption"
  1134. ---help---
  1135. Periodically check for memory corruption in low memory, which
  1136. is suspected to be caused by BIOS. Even when enabled in the
  1137. configuration, it is disabled at runtime. Enable it by
  1138. setting "memory_corruption_check=1" on the kernel command
  1139. line. By default it scans the low 64k of memory every 60
  1140. seconds; see the memory_corruption_check_size and
  1141. memory_corruption_check_period parameters in
  1142. Documentation/kernel-parameters.txt to adjust this.
  1143. When enabled with the default parameters, this option has
  1144. almost no overhead, as it reserves a relatively small amount
  1145. of memory and scans it infrequently. It both detects corruption
  1146. and prevents it from affecting the running system.
  1147. It is, however, intended as a diagnostic tool; if repeatable
  1148. BIOS-originated corruption always affects the same memory,
  1149. you can use memmap= to prevent the kernel from using that
  1150. memory.
  1151. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1152. bool "Set the default setting of memory_corruption_check"
  1153. depends on X86_CHECK_BIOS_CORRUPTION
  1154. default y
  1155. ---help---
  1156. Set whether the default state of memory_corruption_check is
  1157. on or off.
  1158. config X86_RESERVE_LOW
  1159. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1160. default 64
  1161. range 4 640
  1162. ---help---
  1163. Specify the amount of low memory to reserve for the BIOS.
  1164. The first page contains BIOS data structures that the kernel
  1165. must not use, so that page must always be reserved.
  1166. By default we reserve the first 64K of physical RAM, as a
  1167. number of BIOSes are known to corrupt that memory range
  1168. during events such as suspend/resume or monitor cable
  1169. insertion, so it must not be used by the kernel.
  1170. You can set this to 4 if you are absolutely sure that you
  1171. trust the BIOS to get all its memory reservations and usages
  1172. right. If you know your BIOS have problems beyond the
  1173. default 64K area, you can set this to 640 to avoid using the
  1174. entire low memory range.
  1175. If you have doubts about the BIOS (e.g. suspend/resume does
  1176. not work or there's kernel crashes after certain hardware
  1177. hotplug events) then you might want to enable
  1178. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1179. typical corruption patterns.
  1180. Leave this to the default value of 64 if you are unsure.
  1181. config MATH_EMULATION
  1182. bool
  1183. prompt "Math emulation" if X86_32
  1184. ---help---
  1185. Linux can emulate a math coprocessor (used for floating point
  1186. operations) if you don't have one. 486DX and Pentium processors have
  1187. a math coprocessor built in, 486SX and 386 do not, unless you added
  1188. a 487DX or 387, respectively. (The messages during boot time can
  1189. give you some hints here ["man dmesg"].) Everyone needs either a
  1190. coprocessor or this emulation.
  1191. If you don't have a math coprocessor, you need to say Y here; if you
  1192. say Y here even though you have a coprocessor, the coprocessor will
  1193. be used nevertheless. (This behavior can be changed with the kernel
  1194. command line option "no387", which comes handy if your coprocessor
  1195. is broken. Try "man bootparam" or see the documentation of your boot
  1196. loader (lilo or loadlin) about how to pass options to the kernel at
  1197. boot time.) This means that it is a good idea to say Y here if you
  1198. intend to use this kernel on different machines.
  1199. More information about the internals of the Linux math coprocessor
  1200. emulation can be found in <file:arch/x86/math-emu/README>.
  1201. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1202. kernel, it won't hurt.
  1203. config MTRR
  1204. def_bool y
  1205. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1206. ---help---
  1207. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1208. the Memory Type Range Registers (MTRRs) may be used to control
  1209. processor access to memory ranges. This is most useful if you have
  1210. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1211. allows bus write transfers to be combined into a larger transfer
  1212. before bursting over the PCI/AGP bus. This can increase performance
  1213. of image write operations 2.5 times or more. Saying Y here creates a
  1214. /proc/mtrr file which may be used to manipulate your processor's
  1215. MTRRs. Typically the X server should use this.
  1216. This code has a reasonably generic interface so that similar
  1217. control registers on other processors can be easily supported
  1218. as well:
  1219. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1220. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1221. these, the ARRs are used to emulate the MTRRs.
  1222. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1223. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1224. write-combining. All of these processors are supported by this code
  1225. and it makes sense to say Y here if you have one of them.
  1226. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1227. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1228. can lead to all sorts of problems, so it's good to say Y here.
  1229. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1230. just add about 9 KB to your kernel.
  1231. See <file:Documentation/x86/mtrr.txt> for more information.
  1232. config MTRR_SANITIZER
  1233. def_bool y
  1234. prompt "MTRR cleanup support"
  1235. depends on MTRR
  1236. ---help---
  1237. Convert MTRR layout from continuous to discrete, so X drivers can
  1238. add writeback entries.
  1239. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1240. The largest mtrr entry size for a continuous block can be set with
  1241. mtrr_chunk_size.
  1242. If unsure, say Y.
  1243. config MTRR_SANITIZER_ENABLE_DEFAULT
  1244. int "MTRR cleanup enable value (0-1)"
  1245. range 0 1
  1246. default "0"
  1247. depends on MTRR_SANITIZER
  1248. ---help---
  1249. Enable mtrr cleanup default value
  1250. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1251. int "MTRR cleanup spare reg num (0-7)"
  1252. range 0 7
  1253. default "1"
  1254. depends on MTRR_SANITIZER
  1255. ---help---
  1256. mtrr cleanup spare entries default, it can be changed via
  1257. mtrr_spare_reg_nr=N on the kernel command line.
  1258. config X86_PAT
  1259. def_bool y
  1260. prompt "x86 PAT support" if EXPERT
  1261. depends on MTRR
  1262. ---help---
  1263. Use PAT attributes to setup page level cache control.
  1264. PATs are the modern equivalents of MTRRs and are much more
  1265. flexible than MTRRs.
  1266. Say N here if you see bootup problems (boot crash, boot hang,
  1267. spontaneous reboots) or a non-working video driver.
  1268. If unsure, say Y.
  1269. config ARCH_USES_PG_UNCACHED
  1270. def_bool y
  1271. depends on X86_PAT
  1272. config ARCH_RANDOM
  1273. def_bool y
  1274. prompt "x86 architectural random number generator" if EXPERT
  1275. ---help---
  1276. Enable the x86 architectural RDRAND instruction
  1277. (Intel Bull Mountain technology) to generate random numbers.
  1278. If supported, this is a high bandwidth, cryptographically
  1279. secure hardware random number generator.
  1280. config X86_SMAP
  1281. def_bool y
  1282. prompt "Supervisor Mode Access Prevention" if EXPERT
  1283. ---help---
  1284. Supervisor Mode Access Prevention (SMAP) is a security
  1285. feature in newer Intel processors. There is a small
  1286. performance cost if this enabled and turned on; there is
  1287. also a small increase in the kernel size if this is enabled.
  1288. If unsure, say Y.
  1289. config EFI
  1290. bool "EFI runtime service support"
  1291. depends on ACPI
  1292. ---help---
  1293. This enables the kernel to use EFI runtime services that are
  1294. available (such as the EFI variable services).
  1295. This option is only useful on systems that have EFI firmware.
  1296. In addition, you should use the latest ELILO loader available
  1297. at <http://elilo.sourceforge.net> in order to take advantage
  1298. of EFI runtime services. However, even with this option, the
  1299. resultant kernel should continue to boot on existing non-EFI
  1300. platforms.
  1301. config EFI_STUB
  1302. bool "EFI stub support"
  1303. depends on EFI
  1304. ---help---
  1305. This kernel feature allows a bzImage to be loaded directly
  1306. by EFI firmware without the use of a bootloader.
  1307. See Documentation/x86/efi-stub.txt for more information.
  1308. config SECCOMP
  1309. def_bool y
  1310. prompt "Enable seccomp to safely compute untrusted bytecode"
  1311. ---help---
  1312. This kernel feature is useful for number crunching applications
  1313. that may need to compute untrusted bytecode during their
  1314. execution. By using pipes or other transports made available to
  1315. the process as file descriptors supporting the read/write
  1316. syscalls, it's possible to isolate those applications in
  1317. their own address space using seccomp. Once seccomp is
  1318. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1319. and the task is only allowed to execute a few safe syscalls
  1320. defined by each seccomp mode.
  1321. If unsure, say Y. Only embedded should say N here.
  1322. config CC_STACKPROTECTOR
  1323. bool "Enable -fstack-protector buffer overflow detection"
  1324. ---help---
  1325. This option turns on the -fstack-protector GCC feature. This
  1326. feature puts, at the beginning of functions, a canary value on
  1327. the stack just before the return address, and validates
  1328. the value just before actually returning. Stack based buffer
  1329. overflows (that need to overwrite this return address) now also
  1330. overwrite the canary, which gets detected and the attack is then
  1331. neutralized via a kernel panic.
  1332. This feature requires gcc version 4.2 or above, or a distribution
  1333. gcc with the feature backported. Older versions are automatically
  1334. detected and for those versions, this configuration option is
  1335. ignored. (and a warning is printed during bootup)
  1336. source kernel/Kconfig.hz
  1337. config KEXEC
  1338. bool "kexec system call"
  1339. ---help---
  1340. kexec is a system call that implements the ability to shutdown your
  1341. current kernel, and to start another kernel. It is like a reboot
  1342. but it is independent of the system firmware. And like a reboot
  1343. you can start any kernel with it, not just Linux.
  1344. The name comes from the similarity to the exec system call.
  1345. It is an ongoing process to be certain the hardware in a machine
  1346. is properly shutdown, so do not be surprised if this code does not
  1347. initially work for you. It may help to enable device hotplugging
  1348. support. As of this writing the exact hardware interface is
  1349. strongly in flux, so no good recommendation can be made.
  1350. config CRASH_DUMP
  1351. bool "kernel crash dumps"
  1352. depends on X86_64 || (X86_32 && HIGHMEM)
  1353. ---help---
  1354. Generate crash dump after being started by kexec.
  1355. This should be normally only set in special crash dump kernels
  1356. which are loaded in the main kernel with kexec-tools into
  1357. a specially reserved region and then later executed after
  1358. a crash by kdump/kexec. The crash dump kernel must be compiled
  1359. to a memory address not used by the main kernel or BIOS using
  1360. PHYSICAL_START, or it must be built as a relocatable image
  1361. (CONFIG_RELOCATABLE=y).
  1362. For more details see Documentation/kdump/kdump.txt
  1363. config KEXEC_JUMP
  1364. bool "kexec jump (EXPERIMENTAL)"
  1365. depends on EXPERIMENTAL
  1366. depends on KEXEC && HIBERNATION
  1367. ---help---
  1368. Jump between original kernel and kexeced kernel and invoke
  1369. code in physical address mode via KEXEC
  1370. config PHYSICAL_START
  1371. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1372. default "0x1000000"
  1373. ---help---
  1374. This gives the physical address where the kernel is loaded.
  1375. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1376. bzImage will decompress itself to above physical address and
  1377. run from there. Otherwise, bzImage will run from the address where
  1378. it has been loaded by the boot loader and will ignore above physical
  1379. address.
  1380. In normal kdump cases one does not have to set/change this option
  1381. as now bzImage can be compiled as a completely relocatable image
  1382. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1383. address. This option is mainly useful for the folks who don't want
  1384. to use a bzImage for capturing the crash dump and want to use a
  1385. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1386. to be specifically compiled to run from a specific memory area
  1387. (normally a reserved region) and this option comes handy.
  1388. So if you are using bzImage for capturing the crash dump,
  1389. leave the value here unchanged to 0x1000000 and set
  1390. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1391. for capturing the crash dump change this value to start of
  1392. the reserved region. In other words, it can be set based on
  1393. the "X" value as specified in the "crashkernel=YM@XM"
  1394. command line boot parameter passed to the panic-ed
  1395. kernel. Please take a look at Documentation/kdump/kdump.txt
  1396. for more details about crash dumps.
  1397. Usage of bzImage for capturing the crash dump is recommended as
  1398. one does not have to build two kernels. Same kernel can be used
  1399. as production kernel and capture kernel. Above option should have
  1400. gone away after relocatable bzImage support is introduced. But it
  1401. is present because there are users out there who continue to use
  1402. vmlinux for dump capture. This option should go away down the
  1403. line.
  1404. Don't change this unless you know what you are doing.
  1405. config RELOCATABLE
  1406. bool "Build a relocatable kernel"
  1407. default y
  1408. ---help---
  1409. This builds a kernel image that retains relocation information
  1410. so it can be loaded someplace besides the default 1MB.
  1411. The relocations tend to make the kernel binary about 10% larger,
  1412. but are discarded at runtime.
  1413. One use is for the kexec on panic case where the recovery kernel
  1414. must live at a different physical address than the primary
  1415. kernel.
  1416. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1417. it has been loaded at and the compile time physical address
  1418. (CONFIG_PHYSICAL_START) is ignored.
  1419. # Relocation on x86-32 needs some additional build support
  1420. config X86_NEED_RELOCS
  1421. def_bool y
  1422. depends on X86_32 && RELOCATABLE
  1423. config PHYSICAL_ALIGN
  1424. hex "Alignment value to which kernel should be aligned" if X86_32
  1425. default "0x1000000"
  1426. range 0x2000 0x1000000
  1427. ---help---
  1428. This value puts the alignment restrictions on physical address
  1429. where kernel is loaded and run from. Kernel is compiled for an
  1430. address which meets above alignment restriction.
  1431. If bootloader loads the kernel at a non-aligned address and
  1432. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1433. address aligned to above value and run from there.
  1434. If bootloader loads the kernel at a non-aligned address and
  1435. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1436. load address and decompress itself to the address it has been
  1437. compiled for and run from there. The address for which kernel is
  1438. compiled already meets above alignment restrictions. Hence the
  1439. end result is that kernel runs from a physical address meeting
  1440. above alignment restrictions.
  1441. Don't change this unless you know what you are doing.
  1442. config HOTPLUG_CPU
  1443. bool "Support for hot-pluggable CPUs"
  1444. depends on SMP && HOTPLUG
  1445. ---help---
  1446. Say Y here to allow turning CPUs off and on. CPUs can be
  1447. controlled through /sys/devices/system/cpu.
  1448. ( Note: power management support will enable this option
  1449. automatically on SMP systems. )
  1450. Say N if you want to disable CPU hotplug.
  1451. config BOOTPARAM_HOTPLUG_CPU0
  1452. bool "Set default setting of cpu0_hotpluggable"
  1453. default n
  1454. depends on HOTPLUG_CPU && EXPERIMENTAL
  1455. ---help---
  1456. Set whether default state of cpu0_hotpluggable is on or off.
  1457. Say Y here to enable CPU0 hotplug by default. If this switch
  1458. is turned on, there is no need to give cpu0_hotplug kernel
  1459. parameter and the CPU0 hotplug feature is enabled by default.
  1460. Please note: there are two known CPU0 dependencies if you want
  1461. to enable the CPU0 hotplug feature either by this switch or by
  1462. cpu0_hotplug kernel parameter.
  1463. First, resume from hibernate or suspend always starts from CPU0.
  1464. So hibernate and suspend are prevented if CPU0 is offline.
  1465. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1466. offline if any interrupt can not migrate out of CPU0. There may
  1467. be other CPU0 dependencies.
  1468. Please make sure the dependencies are under your control before
  1469. you enable this feature.
  1470. Say N if you don't want to enable CPU0 hotplug feature by default.
  1471. You still can enable the CPU0 hotplug feature at boot by kernel
  1472. parameter cpu0_hotplug.
  1473. config DEBUG_HOTPLUG_CPU0
  1474. def_bool n
  1475. prompt "Debug CPU0 hotplug"
  1476. depends on HOTPLUG_CPU && EXPERIMENTAL
  1477. ---help---
  1478. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1479. soon as possible and boots up userspace with CPU0 offlined. User
  1480. can online CPU0 back after boot time.
  1481. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1482. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1483. compilation or giving cpu0_hotplug kernel parameter at boot.
  1484. If unsure, say N.
  1485. config COMPAT_VDSO
  1486. def_bool y
  1487. prompt "Compat VDSO support"
  1488. depends on X86_32 || IA32_EMULATION
  1489. ---help---
  1490. Map the 32-bit VDSO to the predictable old-style address too.
  1491. Say N here if you are running a sufficiently recent glibc
  1492. version (2.3.3 or later), to remove the high-mapped
  1493. VDSO mapping and to exclusively use the randomized VDSO.
  1494. If unsure, say Y.
  1495. config CMDLINE_BOOL
  1496. bool "Built-in kernel command line"
  1497. ---help---
  1498. Allow for specifying boot arguments to the kernel at
  1499. build time. On some systems (e.g. embedded ones), it is
  1500. necessary or convenient to provide some or all of the
  1501. kernel boot arguments with the kernel itself (that is,
  1502. to not rely on the boot loader to provide them.)
  1503. To compile command line arguments into the kernel,
  1504. set this option to 'Y', then fill in the
  1505. the boot arguments in CONFIG_CMDLINE.
  1506. Systems with fully functional boot loaders (i.e. non-embedded)
  1507. should leave this option set to 'N'.
  1508. config CMDLINE
  1509. string "Built-in kernel command string"
  1510. depends on CMDLINE_BOOL
  1511. default ""
  1512. ---help---
  1513. Enter arguments here that should be compiled into the kernel
  1514. image and used at boot time. If the boot loader provides a
  1515. command line at boot time, it is appended to this string to
  1516. form the full kernel command line, when the system boots.
  1517. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1518. change this behavior.
  1519. In most cases, the command line (whether built-in or provided
  1520. by the boot loader) should specify the device for the root
  1521. file system.
  1522. config CMDLINE_OVERRIDE
  1523. bool "Built-in command line overrides boot loader arguments"
  1524. depends on CMDLINE_BOOL
  1525. ---help---
  1526. Set this option to 'Y' to have the kernel ignore the boot loader
  1527. command line, and use ONLY the built-in command line.
  1528. This is used to work around broken boot loaders. This should
  1529. be set to 'N' under normal conditions.
  1530. endmenu
  1531. config ARCH_ENABLE_MEMORY_HOTPLUG
  1532. def_bool y
  1533. depends on X86_64 || (X86_32 && HIGHMEM)
  1534. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1535. def_bool y
  1536. depends on MEMORY_HOTPLUG
  1537. config USE_PERCPU_NUMA_NODE_ID
  1538. def_bool y
  1539. depends on NUMA
  1540. menu "Power management and ACPI options"
  1541. config ARCH_HIBERNATION_HEADER
  1542. def_bool y
  1543. depends on X86_64 && HIBERNATION
  1544. source "kernel/power/Kconfig"
  1545. source "drivers/acpi/Kconfig"
  1546. source "drivers/sfi/Kconfig"
  1547. config X86_APM_BOOT
  1548. def_bool y
  1549. depends on APM
  1550. menuconfig APM
  1551. tristate "APM (Advanced Power Management) BIOS support"
  1552. depends on X86_32 && PM_SLEEP
  1553. ---help---
  1554. APM is a BIOS specification for saving power using several different
  1555. techniques. This is mostly useful for battery powered laptops with
  1556. APM compliant BIOSes. If you say Y here, the system time will be
  1557. reset after a RESUME operation, the /proc/apm device will provide
  1558. battery status information, and user-space programs will receive
  1559. notification of APM "events" (e.g. battery status change).
  1560. If you select "Y" here, you can disable actual use of the APM
  1561. BIOS by passing the "apm=off" option to the kernel at boot time.
  1562. Note that the APM support is almost completely disabled for
  1563. machines with more than one CPU.
  1564. In order to use APM, you will need supporting software. For location
  1565. and more information, read <file:Documentation/power/apm-acpi.txt>
  1566. and the Battery Powered Linux mini-HOWTO, available from
  1567. <http://www.tldp.org/docs.html#howto>.
  1568. This driver does not spin down disk drives (see the hdparm(8)
  1569. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1570. VESA-compliant "green" monitors.
  1571. This driver does not support the TI 4000M TravelMate and the ACER
  1572. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1573. desktop machines also don't have compliant BIOSes, and this driver
  1574. may cause those machines to panic during the boot phase.
  1575. Generally, if you don't have a battery in your machine, there isn't
  1576. much point in using this driver and you should say N. If you get
  1577. random kernel OOPSes or reboots that don't seem to be related to
  1578. anything, try disabling/enabling this option (or disabling/enabling
  1579. APM in your BIOS).
  1580. Some other things you should try when experiencing seemingly random,
  1581. "weird" problems:
  1582. 1) make sure that you have enough swap space and that it is
  1583. enabled.
  1584. 2) pass the "no-hlt" option to the kernel
  1585. 3) switch on floating point emulation in the kernel and pass
  1586. the "no387" option to the kernel
  1587. 4) pass the "floppy=nodma" option to the kernel
  1588. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1589. all but the first 4 MB of RAM)
  1590. 6) make sure that the CPU is not over clocked.
  1591. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1592. 8) disable the cache from your BIOS settings
  1593. 9) install a fan for the video card or exchange video RAM
  1594. 10) install a better fan for the CPU
  1595. 11) exchange RAM chips
  1596. 12) exchange the motherboard.
  1597. To compile this driver as a module, choose M here: the
  1598. module will be called apm.
  1599. if APM
  1600. config APM_IGNORE_USER_SUSPEND
  1601. bool "Ignore USER SUSPEND"
  1602. ---help---
  1603. This option will ignore USER SUSPEND requests. On machines with a
  1604. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1605. series notebooks, it is necessary to say Y because of a BIOS bug.
  1606. config APM_DO_ENABLE
  1607. bool "Enable PM at boot time"
  1608. ---help---
  1609. Enable APM features at boot time. From page 36 of the APM BIOS
  1610. specification: "When disabled, the APM BIOS does not automatically
  1611. power manage devices, enter the Standby State, enter the Suspend
  1612. State, or take power saving steps in response to CPU Idle calls."
  1613. This driver will make CPU Idle calls when Linux is idle (unless this
  1614. feature is turned off -- see "Do CPU IDLE calls", below). This
  1615. should always save battery power, but more complicated APM features
  1616. will be dependent on your BIOS implementation. You may need to turn
  1617. this option off if your computer hangs at boot time when using APM
  1618. support, or if it beeps continuously instead of suspending. Turn
  1619. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1620. T400CDT. This is off by default since most machines do fine without
  1621. this feature.
  1622. config APM_CPU_IDLE
  1623. depends on CPU_IDLE
  1624. bool "Make CPU Idle calls when idle"
  1625. ---help---
  1626. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1627. On some machines, this can activate improved power savings, such as
  1628. a slowed CPU clock rate, when the machine is idle. These idle calls
  1629. are made after the idle loop has run for some length of time (e.g.,
  1630. 333 mS). On some machines, this will cause a hang at boot time or
  1631. whenever the CPU becomes idle. (On machines with more than one CPU,
  1632. this option does nothing.)
  1633. config APM_DISPLAY_BLANK
  1634. bool "Enable console blanking using APM"
  1635. ---help---
  1636. Enable console blanking using the APM. Some laptops can use this to
  1637. turn off the LCD backlight when the screen blanker of the Linux
  1638. virtual console blanks the screen. Note that this is only used by
  1639. the virtual console screen blanker, and won't turn off the backlight
  1640. when using the X Window system. This also doesn't have anything to
  1641. do with your VESA-compliant power-saving monitor. Further, this
  1642. option doesn't work for all laptops -- it might not turn off your
  1643. backlight at all, or it might print a lot of errors to the console,
  1644. especially if you are using gpm.
  1645. config APM_ALLOW_INTS
  1646. bool "Allow interrupts during APM BIOS calls"
  1647. ---help---
  1648. Normally we disable external interrupts while we are making calls to
  1649. the APM BIOS as a measure to lessen the effects of a badly behaving
  1650. BIOS implementation. The BIOS should reenable interrupts if it
  1651. needs to. Unfortunately, some BIOSes do not -- especially those in
  1652. many of the newer IBM Thinkpads. If you experience hangs when you
  1653. suspend, try setting this to Y. Otherwise, say N.
  1654. endif # APM
  1655. source "drivers/cpufreq/Kconfig"
  1656. source "drivers/cpuidle/Kconfig"
  1657. source "drivers/idle/Kconfig"
  1658. endmenu
  1659. menu "Bus options (PCI etc.)"
  1660. config PCI
  1661. bool "PCI support"
  1662. default y
  1663. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1664. ---help---
  1665. Find out whether you have a PCI motherboard. PCI is the name of a
  1666. bus system, i.e. the way the CPU talks to the other stuff inside
  1667. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1668. VESA. If you have PCI, say Y, otherwise N.
  1669. choice
  1670. prompt "PCI access mode"
  1671. depends on X86_32 && PCI
  1672. default PCI_GOANY
  1673. ---help---
  1674. On PCI systems, the BIOS can be used to detect the PCI devices and
  1675. determine their configuration. However, some old PCI motherboards
  1676. have BIOS bugs and may crash if this is done. Also, some embedded
  1677. PCI-based systems don't have any BIOS at all. Linux can also try to
  1678. detect the PCI hardware directly without using the BIOS.
  1679. With this option, you can specify how Linux should detect the
  1680. PCI devices. If you choose "BIOS", the BIOS will be used,
  1681. if you choose "Direct", the BIOS won't be used, and if you
  1682. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1683. If you choose "Any", the kernel will try MMCONFIG, then the
  1684. direct access method and falls back to the BIOS if that doesn't
  1685. work. If unsure, go with the default, which is "Any".
  1686. config PCI_GOBIOS
  1687. bool "BIOS"
  1688. config PCI_GOMMCONFIG
  1689. bool "MMConfig"
  1690. config PCI_GODIRECT
  1691. bool "Direct"
  1692. config PCI_GOOLPC
  1693. bool "OLPC XO-1"
  1694. depends on OLPC
  1695. config PCI_GOANY
  1696. bool "Any"
  1697. endchoice
  1698. config PCI_BIOS
  1699. def_bool y
  1700. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1701. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1702. config PCI_DIRECT
  1703. def_bool y
  1704. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  1705. config PCI_MMCONFIG
  1706. def_bool y
  1707. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1708. config PCI_OLPC
  1709. def_bool y
  1710. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1711. config PCI_XEN
  1712. def_bool y
  1713. depends on PCI && XEN
  1714. select SWIOTLB_XEN
  1715. config PCI_DOMAINS
  1716. def_bool y
  1717. depends on PCI
  1718. config PCI_MMCONFIG
  1719. bool "Support mmconfig PCI config space access"
  1720. depends on X86_64 && PCI && ACPI
  1721. config PCI_CNB20LE_QUIRK
  1722. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1723. depends on PCI && EXPERIMENTAL
  1724. help
  1725. Read the PCI windows out of the CNB20LE host bridge. This allows
  1726. PCI hotplug to work on systems with the CNB20LE chipset which do
  1727. not have ACPI.
  1728. There's no public spec for this chipset, and this functionality
  1729. is known to be incomplete.
  1730. You should say N unless you know you need this.
  1731. source "drivers/pci/pcie/Kconfig"
  1732. source "drivers/pci/Kconfig"
  1733. # x86_64 have no ISA slots, but can have ISA-style DMA.
  1734. config ISA_DMA_API
  1735. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  1736. default y
  1737. help
  1738. Enables ISA-style DMA support for devices requiring such controllers.
  1739. If unsure, say Y.
  1740. if X86_32
  1741. config ISA
  1742. bool "ISA support"
  1743. ---help---
  1744. Find out whether you have ISA slots on your motherboard. ISA is the
  1745. name of a bus system, i.e. the way the CPU talks to the other stuff
  1746. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1747. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1748. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1749. config EISA
  1750. bool "EISA support"
  1751. depends on ISA
  1752. ---help---
  1753. The Extended Industry Standard Architecture (EISA) bus was
  1754. developed as an open alternative to the IBM MicroChannel bus.
  1755. The EISA bus provided some of the features of the IBM MicroChannel
  1756. bus while maintaining backward compatibility with cards made for
  1757. the older ISA bus. The EISA bus saw limited use between 1988 and
  1758. 1995 when it was made obsolete by the PCI bus.
  1759. Say Y here if you are building a kernel for an EISA-based machine.
  1760. Otherwise, say N.
  1761. source "drivers/eisa/Kconfig"
  1762. config SCx200
  1763. tristate "NatSemi SCx200 support"
  1764. ---help---
  1765. This provides basic support for National Semiconductor's
  1766. (now AMD's) Geode processors. The driver probes for the
  1767. PCI-IDs of several on-chip devices, so its a good dependency
  1768. for other scx200_* drivers.
  1769. If compiled as a module, the driver is named scx200.
  1770. config SCx200HR_TIMER
  1771. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1772. depends on SCx200
  1773. default y
  1774. ---help---
  1775. This driver provides a clocksource built upon the on-chip
  1776. 27MHz high-resolution timer. Its also a workaround for
  1777. NSC Geode SC-1100's buggy TSC, which loses time when the
  1778. processor goes idle (as is done by the scheduler). The
  1779. other workaround is idle=poll boot option.
  1780. config OLPC
  1781. bool "One Laptop Per Child support"
  1782. depends on !X86_PAE
  1783. select GPIOLIB
  1784. select OF
  1785. select OF_PROMTREE
  1786. select IRQ_DOMAIN
  1787. ---help---
  1788. Add support for detecting the unique features of the OLPC
  1789. XO hardware.
  1790. config OLPC_XO1_PM
  1791. bool "OLPC XO-1 Power Management"
  1792. depends on OLPC && MFD_CS5535 && PM_SLEEP
  1793. select MFD_CORE
  1794. ---help---
  1795. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  1796. config OLPC_XO1_RTC
  1797. bool "OLPC XO-1 Real Time Clock"
  1798. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  1799. ---help---
  1800. Add support for the XO-1 real time clock, which can be used as a
  1801. programmable wakeup source.
  1802. config OLPC_XO1_SCI
  1803. bool "OLPC XO-1 SCI extras"
  1804. depends on OLPC && OLPC_XO1_PM
  1805. depends on INPUT=y
  1806. select POWER_SUPPLY
  1807. select GPIO_CS5535
  1808. select MFD_CORE
  1809. ---help---
  1810. Add support for SCI-based features of the OLPC XO-1 laptop:
  1811. - EC-driven system wakeups
  1812. - Power button
  1813. - Ebook switch
  1814. - Lid switch
  1815. - AC adapter status updates
  1816. - Battery status updates
  1817. config OLPC_XO15_SCI
  1818. bool "OLPC XO-1.5 SCI extras"
  1819. depends on OLPC && ACPI
  1820. select POWER_SUPPLY
  1821. ---help---
  1822. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  1823. - EC-driven system wakeups
  1824. - AC adapter status updates
  1825. - Battery status updates
  1826. config ALIX
  1827. bool "PCEngines ALIX System Support (LED setup)"
  1828. select GPIOLIB
  1829. ---help---
  1830. This option enables system support for the PCEngines ALIX.
  1831. At present this just sets up LEDs for GPIO control on
  1832. ALIX2/3/6 boards. However, other system specific setup should
  1833. get added here.
  1834. Note: You must still enable the drivers for GPIO and LED support
  1835. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  1836. Note: You have to set alix.force=1 for boards with Award BIOS.
  1837. config NET5501
  1838. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  1839. select GPIOLIB
  1840. ---help---
  1841. This option enables system support for the Soekris Engineering net5501.
  1842. config GEOS
  1843. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  1844. select GPIOLIB
  1845. depends on DMI
  1846. ---help---
  1847. This option enables system support for the Traverse Technologies GEOS.
  1848. config TS5500
  1849. bool "Technologic Systems TS-5500 platform support"
  1850. depends on MELAN
  1851. select CHECK_SIGNATURE
  1852. select NEW_LEDS
  1853. select LEDS_CLASS
  1854. ---help---
  1855. This option enables system support for the Technologic Systems TS-5500.
  1856. endif # X86_32
  1857. config AMD_NB
  1858. def_bool y
  1859. depends on CPU_SUP_AMD && PCI
  1860. source "drivers/pcmcia/Kconfig"
  1861. source "drivers/pci/hotplug/Kconfig"
  1862. config RAPIDIO
  1863. bool "RapidIO support"
  1864. depends on PCI
  1865. default n
  1866. help
  1867. If you say Y here, the kernel will include drivers and
  1868. infrastructure code to support RapidIO interconnect devices.
  1869. source "drivers/rapidio/Kconfig"
  1870. endmenu
  1871. menu "Executable file formats / Emulations"
  1872. source "fs/Kconfig.binfmt"
  1873. config IA32_EMULATION
  1874. bool "IA32 Emulation"
  1875. depends on X86_64
  1876. select COMPAT_BINFMT_ELF
  1877. select HAVE_UID16
  1878. ---help---
  1879. Include code to run legacy 32-bit programs under a
  1880. 64-bit kernel. You should likely turn this on, unless you're
  1881. 100% sure that you don't have any 32-bit programs left.
  1882. config IA32_AOUT
  1883. tristate "IA32 a.out support"
  1884. depends on IA32_EMULATION
  1885. ---help---
  1886. Support old a.out binaries in the 32bit emulation.
  1887. config X86_X32
  1888. bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
  1889. depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
  1890. ---help---
  1891. Include code to run binaries for the x32 native 32-bit ABI
  1892. for 64-bit processors. An x32 process gets access to the
  1893. full 64-bit register file and wide data path while leaving
  1894. pointers at 32 bits for smaller memory footprint.
  1895. You will need a recent binutils (2.22 or later) with
  1896. elf32_x86_64 support enabled to compile a kernel with this
  1897. option set.
  1898. config COMPAT
  1899. def_bool y
  1900. depends on IA32_EMULATION || X86_X32
  1901. select ARCH_WANT_OLD_COMPAT_IPC
  1902. if COMPAT
  1903. config COMPAT_FOR_U64_ALIGNMENT
  1904. def_bool y
  1905. config SYSVIPC_COMPAT
  1906. def_bool y
  1907. depends on SYSVIPC
  1908. config KEYS_COMPAT
  1909. def_bool y
  1910. depends on KEYS
  1911. endif
  1912. endmenu
  1913. config HAVE_ATOMIC_IOMAP
  1914. def_bool y
  1915. depends on X86_32
  1916. config HAVE_TEXT_POKE_SMP
  1917. bool
  1918. select STOP_MACHINE if SMP
  1919. config X86_DEV_DMA_OPS
  1920. bool
  1921. depends on X86_64 || STA2X11
  1922. config X86_DMA_REMAP
  1923. bool
  1924. depends on STA2X11
  1925. source "net/Kconfig"
  1926. source "drivers/Kconfig"
  1927. source "drivers/firmware/Kconfig"
  1928. source "fs/Kconfig"
  1929. source "arch/x86/Kconfig.debug"
  1930. source "security/Kconfig"
  1931. source "crypto/Kconfig"
  1932. source "arch/x86/kvm/Kconfig"
  1933. source "lib/Kconfig"