Kconfig 85 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. config X86_64
  12. def_bool y
  13. depends on 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select ACPI_LEGACY_TABLES_LOOKUP if ACPI
  18. select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
  19. select ANON_INODES
  20. select ARCH_CLOCKSOURCE_DATA
  21. select ARCH_DISCARD_MEMBLOCK
  22. select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  23. select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
  24. select ARCH_HAS_ELF_RANDOMIZE
  25. select ARCH_HAS_FAST_MULTIPLIER
  26. select ARCH_HAS_GCOV_PROFILE_ALL
  27. select ARCH_HAS_PMEM_API if X86_64
  28. select ARCH_HAS_MMIO_FLUSH
  29. select ARCH_HAS_SG_CHAIN
  30. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  31. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  32. select ARCH_MIGHT_HAVE_PC_PARPORT
  33. select ARCH_MIGHT_HAVE_PC_SERIO
  34. select ARCH_SUPPORTS_ATOMIC_RMW
  35. select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
  36. select ARCH_SUPPORTS_INT128 if X86_64
  37. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  38. select ARCH_USE_BUILTIN_BSWAP
  39. select ARCH_USE_CMPXCHG_LOCKREF if X86_64
  40. select ARCH_USE_QUEUED_RWLOCKS
  41. select ARCH_USE_QUEUED_SPINLOCKS
  42. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
  43. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  44. select ARCH_WANT_FRAME_POINTERS
  45. select ARCH_WANT_IPC_PARSE_VERSION if X86_32
  46. select ARCH_WANT_OPTIONAL_GPIOLIB
  47. select BUILDTIME_EXTABLE_SORT
  48. select CLKEVT_I8253
  49. select CLKSRC_I8253 if X86_32
  50. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  51. select CLOCKSOURCE_WATCHDOG
  52. select CLONE_BACKWARDS if X86_32
  53. select COMPAT_OLD_SIGACTION if IA32_EMULATION
  54. select DCACHE_WORD_ACCESS
  55. select EDAC_ATOMIC_SCRUB
  56. select EDAC_SUPPORT
  57. select GENERIC_CLOCKEVENTS
  58. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  59. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  60. select GENERIC_CMOS_UPDATE
  61. select GENERIC_CPU_AUTOPROBE
  62. select GENERIC_EARLY_IOREMAP
  63. select GENERIC_FIND_FIRST_BIT
  64. select GENERIC_IOMAP
  65. select GENERIC_IRQ_PROBE
  66. select GENERIC_IRQ_SHOW
  67. select GENERIC_PENDING_IRQ if SMP
  68. select GENERIC_SMP_IDLE_THREAD
  69. select GENERIC_STRNCPY_FROM_USER
  70. select GENERIC_STRNLEN_USER
  71. select GENERIC_TIME_VSYSCALL
  72. select HAVE_ACPI_APEI if ACPI
  73. select HAVE_ACPI_APEI_NMI if ACPI
  74. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  75. select HAVE_AOUT if X86_32
  76. select HAVE_ARCH_AUDITSYSCALL
  77. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  78. select HAVE_ARCH_JUMP_LABEL
  79. select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
  80. select HAVE_ARCH_KGDB
  81. select HAVE_ARCH_KMEMCHECK
  82. select HAVE_ARCH_SECCOMP_FILTER
  83. select HAVE_ARCH_SOFT_DIRTY if X86_64
  84. select HAVE_ARCH_TRACEHOOK
  85. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  86. select HAVE_BPF_JIT if X86_64
  87. select HAVE_CC_STACKPROTECTOR
  88. select HAVE_CMPXCHG_DOUBLE
  89. select HAVE_CMPXCHG_LOCAL
  90. select HAVE_CONTEXT_TRACKING if X86_64
  91. select HAVE_COPY_THREAD_TLS
  92. select HAVE_C_RECORDMCOUNT
  93. select HAVE_DEBUG_KMEMLEAK
  94. select HAVE_DEBUG_STACKOVERFLOW
  95. select HAVE_DMA_API_DEBUG
  96. select HAVE_DMA_ATTRS
  97. select HAVE_DMA_CONTIGUOUS
  98. select HAVE_DYNAMIC_FTRACE
  99. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  100. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  101. select HAVE_FENTRY if X86_64
  102. select HAVE_FTRACE_MCOUNT_RECORD
  103. select HAVE_FUNCTION_GRAPH_FP_TEST
  104. select HAVE_FUNCTION_GRAPH_TRACER
  105. select HAVE_FUNCTION_TRACER
  106. select HAVE_GENERIC_DMA_COHERENT if X86_32
  107. select HAVE_HW_BREAKPOINT
  108. select HAVE_IDE
  109. select HAVE_IOREMAP_PROT
  110. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  111. select HAVE_IRQ_TIME_ACCOUNTING
  112. select HAVE_KERNEL_BZIP2
  113. select HAVE_KERNEL_GZIP
  114. select HAVE_KERNEL_LZ4
  115. select HAVE_KERNEL_LZMA
  116. select HAVE_KERNEL_LZO
  117. select HAVE_KERNEL_XZ
  118. select HAVE_KPROBES
  119. select HAVE_KPROBES_ON_FTRACE
  120. select HAVE_KRETPROBES
  121. select HAVE_KVM
  122. select HAVE_LIVEPATCH if X86_64
  123. select HAVE_MEMBLOCK
  124. select HAVE_MEMBLOCK_NODE_MAP
  125. select HAVE_MIXED_BREAKPOINTS_REGS
  126. select HAVE_OPROFILE
  127. select HAVE_OPTPROBES
  128. select HAVE_PCSPKR_PLATFORM
  129. select HAVE_PERF_EVENTS
  130. select HAVE_PERF_EVENTS_NMI
  131. select HAVE_PERF_REGS
  132. select HAVE_PERF_USER_STACK_DUMP
  133. select HAVE_REGS_AND_STACK_ACCESS_API
  134. select HAVE_SYSCALL_TRACEPOINTS
  135. select HAVE_UID16 if X86_32 || IA32_EMULATION
  136. select HAVE_UNSTABLE_SCHED_CLOCK
  137. select HAVE_USER_RETURN_NOTIFIER
  138. select IRQ_FORCED_THREADING
  139. select MODULES_USE_ELF_RELA if X86_64
  140. select MODULES_USE_ELF_REL if X86_32
  141. select OLD_SIGACTION if X86_32
  142. select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
  143. select PERF_EVENTS
  144. select RTC_LIB
  145. select SPARSE_IRQ
  146. select SRCU
  147. select SYSCTL_EXCEPTION_TRACE
  148. select USER_STACKTRACE_SUPPORT
  149. select VIRT_TO_BUS
  150. select X86_DEV_DMA_OPS if X86_64
  151. select X86_FEATURE_NAMES if PROC_FS
  152. config INSTRUCTION_DECODER
  153. def_bool y
  154. depends on KPROBES || PERF_EVENTS || UPROBES
  155. config PERF_EVENTS_INTEL_UNCORE
  156. def_bool y
  157. depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
  158. config OUTPUT_FORMAT
  159. string
  160. default "elf32-i386" if X86_32
  161. default "elf64-x86-64" if X86_64
  162. config ARCH_DEFCONFIG
  163. string
  164. default "arch/x86/configs/i386_defconfig" if X86_32
  165. default "arch/x86/configs/x86_64_defconfig" if X86_64
  166. config LOCKDEP_SUPPORT
  167. def_bool y
  168. config STACKTRACE_SUPPORT
  169. def_bool y
  170. config HAVE_LATENCYTOP_SUPPORT
  171. def_bool y
  172. config MMU
  173. def_bool y
  174. config SBUS
  175. bool
  176. config NEED_DMA_MAP_STATE
  177. def_bool y
  178. depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
  179. config NEED_SG_DMA_LENGTH
  180. def_bool y
  181. config GENERIC_ISA_DMA
  182. def_bool y
  183. depends on ISA_DMA_API
  184. config GENERIC_BUG
  185. def_bool y
  186. depends on BUG
  187. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  188. config GENERIC_BUG_RELATIVE_POINTERS
  189. bool
  190. config GENERIC_HWEIGHT
  191. def_bool y
  192. config ARCH_MAY_HAVE_PC_FDC
  193. def_bool y
  194. depends on ISA_DMA_API
  195. config RWSEM_XCHGADD_ALGORITHM
  196. def_bool y
  197. config GENERIC_CALIBRATE_DELAY
  198. def_bool y
  199. config ARCH_HAS_CPU_RELAX
  200. def_bool y
  201. config ARCH_HAS_CACHE_LINE_SIZE
  202. def_bool y
  203. config HAVE_SETUP_PER_CPU_AREA
  204. def_bool y
  205. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  206. def_bool y
  207. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  208. def_bool y
  209. config ARCH_HIBERNATION_POSSIBLE
  210. def_bool y
  211. config ARCH_SUSPEND_POSSIBLE
  212. def_bool y
  213. config ARCH_WANT_HUGE_PMD_SHARE
  214. def_bool y
  215. config ARCH_WANT_GENERAL_HUGETLB
  216. def_bool y
  217. config ZONE_DMA32
  218. def_bool y if X86_64
  219. config AUDIT_ARCH
  220. def_bool y if X86_64
  221. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  222. def_bool y
  223. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  224. def_bool y
  225. config KASAN_SHADOW_OFFSET
  226. hex
  227. depends on KASAN
  228. default 0xdffffc0000000000
  229. config HAVE_INTEL_TXT
  230. def_bool y
  231. depends on INTEL_IOMMU && ACPI
  232. config X86_32_SMP
  233. def_bool y
  234. depends on X86_32 && SMP
  235. config X86_64_SMP
  236. def_bool y
  237. depends on X86_64 && SMP
  238. config X86_32_LAZY_GS
  239. def_bool y
  240. depends on X86_32 && !CC_STACKPROTECTOR
  241. config ARCH_HWEIGHT_CFLAGS
  242. string
  243. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  244. 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
  245. config ARCH_SUPPORTS_UPROBES
  246. def_bool y
  247. config FIX_EARLYCON_MEM
  248. def_bool y
  249. config PGTABLE_LEVELS
  250. int
  251. default 4 if X86_64
  252. default 3 if X86_PAE
  253. default 2
  254. source "init/Kconfig"
  255. source "kernel/Kconfig.freezer"
  256. menu "Processor type and features"
  257. config ZONE_DMA
  258. bool "DMA memory allocation support" if EXPERT
  259. default y
  260. help
  261. DMA memory allocation support allows devices with less than 32-bit
  262. addressing to allocate within the first 16MB of address space.
  263. Disable if no such devices will be used.
  264. If unsure, say Y.
  265. config SMP
  266. bool "Symmetric multi-processing support"
  267. ---help---
  268. This enables support for systems with more than one CPU. If you have
  269. a system with only one CPU, say N. If you have a system with more
  270. than one CPU, say Y.
  271. If you say N here, the kernel will run on uni- and multiprocessor
  272. machines, but will use only one CPU of a multiprocessor machine. If
  273. you say Y here, the kernel will run on many, but not all,
  274. uniprocessor machines. On a uniprocessor machine, the kernel
  275. will run faster if you say N here.
  276. Note that if you say Y here and choose architecture "586" or
  277. "Pentium" under "Processor family", the kernel will not work on 486
  278. architectures. Similarly, multiprocessor kernels for the "PPro"
  279. architecture may not work on all Pentium based boards.
  280. People using multiprocessor machines who say Y here should also say
  281. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  282. Management" code will be disabled if you say Y here.
  283. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  284. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  285. <http://www.tldp.org/docs.html#howto>.
  286. If you don't know what to do here, say N.
  287. config X86_FEATURE_NAMES
  288. bool "Processor feature human-readable names" if EMBEDDED
  289. default y
  290. ---help---
  291. This option compiles in a table of x86 feature bits and corresponding
  292. names. This is required to support /proc/cpuinfo and a few kernel
  293. messages. You can disable this to save space, at the expense of
  294. making those few kernel messages show numeric feature bits instead.
  295. If in doubt, say Y.
  296. config X86_X2APIC
  297. bool "Support x2apic"
  298. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  299. ---help---
  300. This enables x2apic support on CPUs that have this feature.
  301. This allows 32-bit apic IDs (so it can support very large systems),
  302. and accesses the local apic via MSRs not via mmio.
  303. If you don't know what to do here, say N.
  304. config X86_MPPARSE
  305. bool "Enable MPS table" if ACPI || SFI
  306. default y
  307. depends on X86_LOCAL_APIC
  308. ---help---
  309. For old smp systems that do not have proper acpi support. Newer systems
  310. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  311. config X86_BIGSMP
  312. bool "Support for big SMP systems with more than 8 CPUs"
  313. depends on X86_32 && SMP
  314. ---help---
  315. This option is needed for the systems that have more than 8 CPUs
  316. config GOLDFISH
  317. def_bool y
  318. depends on X86_GOLDFISH
  319. if X86_32
  320. config X86_EXTENDED_PLATFORM
  321. bool "Support for extended (non-PC) x86 platforms"
  322. default y
  323. ---help---
  324. If you disable this option then the kernel will only support
  325. standard PC platforms. (which covers the vast majority of
  326. systems out there.)
  327. If you enable this option then you'll be able to select support
  328. for the following (non-PC) 32 bit x86 platforms:
  329. Goldfish (Android emulator)
  330. AMD Elan
  331. RDC R-321x SoC
  332. SGI 320/540 (Visual Workstation)
  333. STA2X11-based (e.g. Northville)
  334. Moorestown MID devices
  335. If you have one of these systems, or if you want to build a
  336. generic distribution kernel, say Y here - otherwise say N.
  337. endif
  338. if X86_64
  339. config X86_EXTENDED_PLATFORM
  340. bool "Support for extended (non-PC) x86 platforms"
  341. default y
  342. ---help---
  343. If you disable this option then the kernel will only support
  344. standard PC platforms. (which covers the vast majority of
  345. systems out there.)
  346. If you enable this option then you'll be able to select support
  347. for the following (non-PC) 64 bit x86 platforms:
  348. Numascale NumaChip
  349. ScaleMP vSMP
  350. SGI Ultraviolet
  351. If you have one of these systems, or if you want to build a
  352. generic distribution kernel, say Y here - otherwise say N.
  353. endif
  354. # This is an alphabetically sorted list of 64 bit extended platforms
  355. # Please maintain the alphabetic order if and when there are additions
  356. config X86_NUMACHIP
  357. bool "Numascale NumaChip"
  358. depends on X86_64
  359. depends on X86_EXTENDED_PLATFORM
  360. depends on NUMA
  361. depends on SMP
  362. depends on X86_X2APIC
  363. depends on PCI_MMCONFIG
  364. ---help---
  365. Adds support for Numascale NumaChip large-SMP systems. Needed to
  366. enable more than ~168 cores.
  367. If you don't have one of these, you should say N here.
  368. config X86_VSMP
  369. bool "ScaleMP vSMP"
  370. select HYPERVISOR_GUEST
  371. select PARAVIRT
  372. depends on X86_64 && PCI
  373. depends on X86_EXTENDED_PLATFORM
  374. depends on SMP
  375. ---help---
  376. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  377. supposed to run on these EM64T-based machines. Only choose this option
  378. if you have one of these machines.
  379. config X86_UV
  380. bool "SGI Ultraviolet"
  381. depends on X86_64
  382. depends on X86_EXTENDED_PLATFORM
  383. depends on NUMA
  384. depends on X86_X2APIC
  385. depends on PCI
  386. ---help---
  387. This option is needed in order to support SGI Ultraviolet systems.
  388. If you don't have one of these, you should say N here.
  389. # Following is an alphabetically sorted list of 32 bit extended platforms
  390. # Please maintain the alphabetic order if and when there are additions
  391. config X86_GOLDFISH
  392. bool "Goldfish (Virtual Platform)"
  393. depends on X86_EXTENDED_PLATFORM
  394. ---help---
  395. Enable support for the Goldfish virtual platform used primarily
  396. for Android development. Unless you are building for the Android
  397. Goldfish emulator say N here.
  398. config X86_INTEL_CE
  399. bool "CE4100 TV platform"
  400. depends on PCI
  401. depends on PCI_GODIRECT
  402. depends on X86_IO_APIC
  403. depends on X86_32
  404. depends on X86_EXTENDED_PLATFORM
  405. select X86_REBOOTFIXUPS
  406. select OF
  407. select OF_EARLY_FLATTREE
  408. ---help---
  409. Select for the Intel CE media processor (CE4100) SOC.
  410. This option compiles in support for the CE4100 SOC for settop
  411. boxes and media devices.
  412. config X86_INTEL_MID
  413. bool "Intel MID platform support"
  414. depends on X86_32
  415. depends on X86_EXTENDED_PLATFORM
  416. depends on X86_PLATFORM_DEVICES
  417. depends on PCI
  418. depends on PCI_GOANY
  419. depends on X86_IO_APIC
  420. select SFI
  421. select I2C
  422. select DW_APB_TIMER
  423. select APB_TIMER
  424. select INTEL_SCU_IPC
  425. select MFD_INTEL_MSIC
  426. ---help---
  427. Select to build a kernel capable of supporting Intel MID (Mobile
  428. Internet Device) platform systems which do not have the PCI legacy
  429. interfaces. If you are building for a PC class system say N here.
  430. Intel MID platforms are based on an Intel processor and chipset which
  431. consume less power than most of the x86 derivatives.
  432. config X86_INTEL_QUARK
  433. bool "Intel Quark platform support"
  434. depends on X86_32
  435. depends on X86_EXTENDED_PLATFORM
  436. depends on X86_PLATFORM_DEVICES
  437. depends on X86_TSC
  438. depends on PCI
  439. depends on PCI_GOANY
  440. depends on X86_IO_APIC
  441. select IOSF_MBI
  442. select INTEL_IMR
  443. select COMMON_CLK
  444. ---help---
  445. Select to include support for Quark X1000 SoC.
  446. Say Y here if you have a Quark based system such as the Arduino
  447. compatible Intel Galileo.
  448. config X86_INTEL_LPSS
  449. bool "Intel Low Power Subsystem Support"
  450. depends on ACPI
  451. select COMMON_CLK
  452. select PINCTRL
  453. ---help---
  454. Select to build support for Intel Low Power Subsystem such as
  455. found on Intel Lynxpoint PCH. Selecting this option enables
  456. things like clock tree (common clock framework) and pincontrol
  457. which are needed by the LPSS peripheral drivers.
  458. config X86_AMD_PLATFORM_DEVICE
  459. bool "AMD ACPI2Platform devices support"
  460. depends on ACPI
  461. select COMMON_CLK
  462. select PINCTRL
  463. ---help---
  464. Select to interpret AMD specific ACPI device to platform device
  465. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  466. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  467. implemented under PINCTRL subsystem.
  468. config IOSF_MBI
  469. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  470. depends on PCI
  471. ---help---
  472. This option enables sideband register access support for Intel SoC
  473. platforms. On these platforms the IOSF sideband is used in lieu of
  474. MSR's for some register accesses, mostly but not limited to thermal
  475. and power. Drivers may query the availability of this device to
  476. determine if they need the sideband in order to work on these
  477. platforms. The sideband is available on the following SoC products.
  478. This list is not meant to be exclusive.
  479. - BayTrail
  480. - Braswell
  481. - Quark
  482. You should say Y if you are running a kernel on one of these SoC's.
  483. config IOSF_MBI_DEBUG
  484. bool "Enable IOSF sideband access through debugfs"
  485. depends on IOSF_MBI && DEBUG_FS
  486. ---help---
  487. Select this option to expose the IOSF sideband access registers (MCR,
  488. MDR, MCRX) through debugfs to write and read register information from
  489. different units on the SoC. This is most useful for obtaining device
  490. state information for debug and analysis. As this is a general access
  491. mechanism, users of this option would have specific knowledge of the
  492. device they want to access.
  493. If you don't require the option or are in doubt, say N.
  494. config X86_RDC321X
  495. bool "RDC R-321x SoC"
  496. depends on X86_32
  497. depends on X86_EXTENDED_PLATFORM
  498. select M486
  499. select X86_REBOOTFIXUPS
  500. ---help---
  501. This option is needed for RDC R-321x system-on-chip, also known
  502. as R-8610-(G).
  503. If you don't have one of these chips, you should say N here.
  504. config X86_32_NON_STANDARD
  505. bool "Support non-standard 32-bit SMP architectures"
  506. depends on X86_32 && SMP
  507. depends on X86_EXTENDED_PLATFORM
  508. ---help---
  509. This option compiles in the bigsmp and STA2X11 default
  510. subarchitectures. It is intended for a generic binary
  511. kernel. If you select them all, kernel will probe it one by
  512. one and will fallback to default.
  513. # Alphabetically sorted list of Non standard 32 bit platforms
  514. config X86_SUPPORTS_MEMORY_FAILURE
  515. def_bool y
  516. # MCE code calls memory_failure():
  517. depends on X86_MCE
  518. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  519. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  520. depends on X86_64 || !SPARSEMEM
  521. select ARCH_SUPPORTS_MEMORY_FAILURE
  522. config STA2X11
  523. bool "STA2X11 Companion Chip Support"
  524. depends on X86_32_NON_STANDARD && PCI
  525. select X86_DEV_DMA_OPS
  526. select X86_DMA_REMAP
  527. select SWIOTLB
  528. select MFD_STA2X11
  529. select ARCH_REQUIRE_GPIOLIB
  530. default n
  531. ---help---
  532. This adds support for boards based on the STA2X11 IO-Hub,
  533. a.k.a. "ConneXt". The chip is used in place of the standard
  534. PC chipset, so all "standard" peripherals are missing. If this
  535. option is selected the kernel will still be able to boot on
  536. standard PC machines.
  537. config X86_32_IRIS
  538. tristate "Eurobraille/Iris poweroff module"
  539. depends on X86_32
  540. ---help---
  541. The Iris machines from EuroBraille do not have APM or ACPI support
  542. to shut themselves down properly. A special I/O sequence is
  543. needed to do so, which is what this module does at
  544. kernel shutdown.
  545. This is only for Iris machines from EuroBraille.
  546. If unused, say N.
  547. config SCHED_OMIT_FRAME_POINTER
  548. def_bool y
  549. prompt "Single-depth WCHAN output"
  550. depends on X86
  551. ---help---
  552. Calculate simpler /proc/<PID>/wchan values. If this option
  553. is disabled then wchan values will recurse back to the
  554. caller function. This provides more accurate wchan values,
  555. at the expense of slightly more scheduling overhead.
  556. If in doubt, say "Y".
  557. menuconfig HYPERVISOR_GUEST
  558. bool "Linux guest support"
  559. ---help---
  560. Say Y here to enable options for running Linux under various hyper-
  561. visors. This option enables basic hypervisor detection and platform
  562. setup.
  563. If you say N, all options in this submenu will be skipped and
  564. disabled, and Linux guest support won't be built in.
  565. if HYPERVISOR_GUEST
  566. config PARAVIRT
  567. bool "Enable paravirtualization code"
  568. ---help---
  569. This changes the kernel so it can modify itself when it is run
  570. under a hypervisor, potentially improving performance significantly
  571. over full virtualization. However, when run without a hypervisor
  572. the kernel is theoretically slower and slightly larger.
  573. config PARAVIRT_DEBUG
  574. bool "paravirt-ops debugging"
  575. depends on PARAVIRT && DEBUG_KERNEL
  576. ---help---
  577. Enable to debug paravirt_ops internals. Specifically, BUG if
  578. a paravirt_op is missing when it is called.
  579. config PARAVIRT_SPINLOCKS
  580. bool "Paravirtualization layer for spinlocks"
  581. depends on PARAVIRT && SMP
  582. select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
  583. ---help---
  584. Paravirtualized spinlocks allow a pvops backend to replace the
  585. spinlock implementation with something virtualization-friendly
  586. (for example, block the virtual CPU rather than spinning).
  587. It has a minimal impact on native kernels and gives a nice performance
  588. benefit on paravirtualized KVM / Xen kernels.
  589. If you are unsure how to answer this question, answer Y.
  590. source "arch/x86/xen/Kconfig"
  591. config KVM_GUEST
  592. bool "KVM Guest support (including kvmclock)"
  593. depends on PARAVIRT
  594. select PARAVIRT_CLOCK
  595. default y
  596. ---help---
  597. This option enables various optimizations for running under the KVM
  598. hypervisor. It includes a paravirtualized clock, so that instead
  599. of relying on a PIT (or probably other) emulation by the
  600. underlying device model, the host provides the guest with
  601. timing infrastructure such as time of day, and system time
  602. config KVM_DEBUG_FS
  603. bool "Enable debug information for KVM Guests in debugfs"
  604. depends on KVM_GUEST && DEBUG_FS
  605. default n
  606. ---help---
  607. This option enables collection of various statistics for KVM guest.
  608. Statistics are displayed in debugfs filesystem. Enabling this option
  609. may incur significant overhead.
  610. source "arch/x86/lguest/Kconfig"
  611. config PARAVIRT_TIME_ACCOUNTING
  612. bool "Paravirtual steal time accounting"
  613. depends on PARAVIRT
  614. default n
  615. ---help---
  616. Select this option to enable fine granularity task steal time
  617. accounting. Time spent executing other tasks in parallel with
  618. the current vCPU is discounted from the vCPU power. To account for
  619. that, there can be a small performance impact.
  620. If in doubt, say N here.
  621. config PARAVIRT_CLOCK
  622. bool
  623. endif #HYPERVISOR_GUEST
  624. config NO_BOOTMEM
  625. def_bool y
  626. source "arch/x86/Kconfig.cpu"
  627. config HPET_TIMER
  628. def_bool X86_64
  629. prompt "HPET Timer Support" if X86_32
  630. ---help---
  631. Use the IA-PC HPET (High Precision Event Timer) to manage
  632. time in preference to the PIT and RTC, if a HPET is
  633. present.
  634. HPET is the next generation timer replacing legacy 8254s.
  635. The HPET provides a stable time base on SMP
  636. systems, unlike the TSC, but it is more expensive to access,
  637. as it is off-chip. You can find the HPET spec at
  638. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  639. You can safely choose Y here. However, HPET will only be
  640. activated if the platform and the BIOS support this feature.
  641. Otherwise the 8254 will be used for timing services.
  642. Choose N to continue using the legacy 8254 timer.
  643. config HPET_EMULATE_RTC
  644. def_bool y
  645. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  646. config APB_TIMER
  647. def_bool y if X86_INTEL_MID
  648. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  649. select DW_APB_TIMER
  650. depends on X86_INTEL_MID && SFI
  651. help
  652. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  653. The APBT provides a stable time base on SMP
  654. systems, unlike the TSC, but it is more expensive to access,
  655. as it is off-chip. APB timers are always running regardless of CPU
  656. C states, they are used as per CPU clockevent device when possible.
  657. # Mark as expert because too many people got it wrong.
  658. # The code disables itself when not needed.
  659. config DMI
  660. default y
  661. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  662. bool "Enable DMI scanning" if EXPERT
  663. ---help---
  664. Enabled scanning of DMI to identify machine quirks. Say Y
  665. here unless you have verified that your setup is not
  666. affected by entries in the DMI blacklist. Required by PNP
  667. BIOS code.
  668. config GART_IOMMU
  669. bool "Old AMD GART IOMMU support"
  670. select SWIOTLB
  671. depends on X86_64 && PCI && AMD_NB
  672. ---help---
  673. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  674. GART based hardware IOMMUs.
  675. The GART supports full DMA access for devices with 32-bit access
  676. limitations, on systems with more than 3 GB. This is usually needed
  677. for USB, sound, many IDE/SATA chipsets and some other devices.
  678. Newer systems typically have a modern AMD IOMMU, supported via
  679. the CONFIG_AMD_IOMMU=y config option.
  680. In normal configurations this driver is only active when needed:
  681. there's more than 3 GB of memory and the system contains a
  682. 32-bit limited device.
  683. If unsure, say Y.
  684. config CALGARY_IOMMU
  685. bool "IBM Calgary IOMMU support"
  686. select SWIOTLB
  687. depends on X86_64 && PCI
  688. ---help---
  689. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  690. systems. Needed to run systems with more than 3GB of memory
  691. properly with 32-bit PCI devices that do not support DAC
  692. (Double Address Cycle). Calgary also supports bus level
  693. isolation, where all DMAs pass through the IOMMU. This
  694. prevents them from going anywhere except their intended
  695. destination. This catches hard-to-find kernel bugs and
  696. mis-behaving drivers and devices that do not use the DMA-API
  697. properly to set up their DMA buffers. The IOMMU can be
  698. turned off at boot time with the iommu=off parameter.
  699. Normally the kernel will make the right choice by itself.
  700. If unsure, say Y.
  701. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  702. def_bool y
  703. prompt "Should Calgary be enabled by default?"
  704. depends on CALGARY_IOMMU
  705. ---help---
  706. Should Calgary be enabled by default? if you choose 'y', Calgary
  707. will be used (if it exists). If you choose 'n', Calgary will not be
  708. used even if it exists. If you choose 'n' and would like to use
  709. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  710. If unsure, say Y.
  711. # need this always selected by IOMMU for the VIA workaround
  712. config SWIOTLB
  713. def_bool y if X86_64
  714. ---help---
  715. Support for software bounce buffers used on x86-64 systems
  716. which don't have a hardware IOMMU. Using this PCI devices
  717. which can only access 32-bits of memory can be used on systems
  718. with more than 3 GB of memory.
  719. If unsure, say Y.
  720. config IOMMU_HELPER
  721. def_bool y
  722. depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
  723. config MAXSMP
  724. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  725. depends on X86_64 && SMP && DEBUG_KERNEL
  726. select CPUMASK_OFFSTACK
  727. ---help---
  728. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  729. If unsure, say N.
  730. config NR_CPUS
  731. int "Maximum number of CPUs" if SMP && !MAXSMP
  732. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  733. range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
  734. range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
  735. default "1" if !SMP
  736. default "8192" if MAXSMP
  737. default "32" if SMP && X86_BIGSMP
  738. default "8" if SMP && X86_32
  739. default "64" if SMP
  740. ---help---
  741. This allows you to specify the maximum number of CPUs which this
  742. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  743. supported value is 8192, otherwise the maximum value is 512. The
  744. minimum value which makes sense is 2.
  745. This is purely to save memory - each supported CPU adds
  746. approximately eight kilobytes to the kernel image.
  747. config SCHED_SMT
  748. bool "SMT (Hyperthreading) scheduler support"
  749. depends on SMP
  750. ---help---
  751. SMT scheduler support improves the CPU scheduler's decision making
  752. when dealing with Intel Pentium 4 chips with HyperThreading at a
  753. cost of slightly increased overhead in some places. If unsure say
  754. N here.
  755. config SCHED_MC
  756. def_bool y
  757. prompt "Multi-core scheduler support"
  758. depends on SMP
  759. ---help---
  760. Multi-core scheduler support improves the CPU scheduler's decision
  761. making when dealing with multi-core CPU chips at a cost of slightly
  762. increased overhead in some places. If unsure say N here.
  763. source "kernel/Kconfig.preempt"
  764. config UP_LATE_INIT
  765. def_bool y
  766. depends on !SMP && X86_LOCAL_APIC
  767. config X86_UP_APIC
  768. bool "Local APIC support on uniprocessors" if !PCI_MSI
  769. default PCI_MSI
  770. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  771. ---help---
  772. A local APIC (Advanced Programmable Interrupt Controller) is an
  773. integrated interrupt controller in the CPU. If you have a single-CPU
  774. system which has a processor with a local APIC, you can say Y here to
  775. enable and use it. If you say Y here even though your machine doesn't
  776. have a local APIC, then the kernel will still run with no slowdown at
  777. all. The local APIC supports CPU-generated self-interrupts (timer,
  778. performance counters), and the NMI watchdog which detects hard
  779. lockups.
  780. config X86_UP_IOAPIC
  781. bool "IO-APIC support on uniprocessors"
  782. depends on X86_UP_APIC
  783. ---help---
  784. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  785. SMP-capable replacement for PC-style interrupt controllers. Most
  786. SMP systems and many recent uniprocessor systems have one.
  787. If you have a single-CPU system with an IO-APIC, you can say Y here
  788. to use it. If you say Y here even though your machine doesn't have
  789. an IO-APIC, then the kernel will still run with no slowdown at all.
  790. config X86_LOCAL_APIC
  791. def_bool y
  792. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  793. select IRQ_DOMAIN_HIERARCHY
  794. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  795. config X86_IO_APIC
  796. def_bool y
  797. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  798. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  799. bool "Reroute for broken boot IRQs"
  800. depends on X86_IO_APIC
  801. ---help---
  802. This option enables a workaround that fixes a source of
  803. spurious interrupts. This is recommended when threaded
  804. interrupt handling is used on systems where the generation of
  805. superfluous "boot interrupts" cannot be disabled.
  806. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  807. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  808. kernel does during interrupt handling). On chipsets where this
  809. boot IRQ generation cannot be disabled, this workaround keeps
  810. the original IRQ line masked so that only the equivalent "boot
  811. IRQ" is delivered to the CPUs. The workaround also tells the
  812. kernel to set up the IRQ handler on the boot IRQ line. In this
  813. way only one interrupt is delivered to the kernel. Otherwise
  814. the spurious second interrupt may cause the kernel to bring
  815. down (vital) interrupt lines.
  816. Only affects "broken" chipsets. Interrupt sharing may be
  817. increased on these systems.
  818. config X86_MCE
  819. bool "Machine Check / overheating reporting"
  820. select GENERIC_ALLOCATOR
  821. default y
  822. ---help---
  823. Machine Check support allows the processor to notify the
  824. kernel if it detects a problem (e.g. overheating, data corruption).
  825. The action the kernel takes depends on the severity of the problem,
  826. ranging from warning messages to halting the machine.
  827. config X86_MCE_INTEL
  828. def_bool y
  829. prompt "Intel MCE features"
  830. depends on X86_MCE && X86_LOCAL_APIC
  831. ---help---
  832. Additional support for intel specific MCE features such as
  833. the thermal monitor.
  834. config X86_MCE_AMD
  835. def_bool y
  836. prompt "AMD MCE features"
  837. depends on X86_MCE && X86_LOCAL_APIC
  838. ---help---
  839. Additional support for AMD specific MCE features such as
  840. the DRAM Error Threshold.
  841. config X86_ANCIENT_MCE
  842. bool "Support for old Pentium 5 / WinChip machine checks"
  843. depends on X86_32 && X86_MCE
  844. ---help---
  845. Include support for machine check handling on old Pentium 5 or WinChip
  846. systems. These typically need to be enabled explicitly on the command
  847. line.
  848. config X86_MCE_THRESHOLD
  849. depends on X86_MCE_AMD || X86_MCE_INTEL
  850. def_bool y
  851. config X86_MCE_INJECT
  852. depends on X86_MCE
  853. tristate "Machine check injector support"
  854. ---help---
  855. Provide support for injecting machine checks for testing purposes.
  856. If you don't know what a machine check is and you don't do kernel
  857. QA it is safe to say n.
  858. config X86_THERMAL_VECTOR
  859. def_bool y
  860. depends on X86_MCE_INTEL
  861. config X86_LEGACY_VM86
  862. bool "Legacy VM86 support"
  863. default n
  864. depends on X86_32
  865. ---help---
  866. This option allows user programs to put the CPU into V8086
  867. mode, which is an 80286-era approximation of 16-bit real mode.
  868. Some very old versions of X and/or vbetool require this option
  869. for user mode setting. Similarly, DOSEMU will use it if
  870. available to accelerate real mode DOS programs. However, any
  871. recent version of DOSEMU, X, or vbetool should be fully
  872. functional even without kernel VM86 support, as they will all
  873. fall back to software emulation. Nevertheless, if you are using
  874. a 16-bit DOS program where 16-bit performance matters, vm86
  875. mode might be faster than emulation and you might want to
  876. enable this option.
  877. Note that any app that works on a 64-bit kernel is unlikely to
  878. need this option, as 64-bit kernels don't, and can't, support
  879. V8086 mode. This option is also unrelated to 16-bit protected
  880. mode and is not needed to run most 16-bit programs under Wine.
  881. Enabling this option increases the complexity of the kernel
  882. and slows down exception handling a tiny bit.
  883. If unsure, say N here.
  884. config VM86
  885. bool
  886. default X86_LEGACY_VM86
  887. config X86_16BIT
  888. bool "Enable support for 16-bit segments" if EXPERT
  889. default y
  890. depends on MODIFY_LDT_SYSCALL
  891. ---help---
  892. This option is required by programs like Wine to run 16-bit
  893. protected mode legacy code on x86 processors. Disabling
  894. this option saves about 300 bytes on i386, or around 6K text
  895. plus 16K runtime memory on x86-64,
  896. config X86_ESPFIX32
  897. def_bool y
  898. depends on X86_16BIT && X86_32
  899. config X86_ESPFIX64
  900. def_bool y
  901. depends on X86_16BIT && X86_64
  902. config X86_VSYSCALL_EMULATION
  903. bool "Enable vsyscall emulation" if EXPERT
  904. default y
  905. depends on X86_64
  906. ---help---
  907. This enables emulation of the legacy vsyscall page. Disabling
  908. it is roughly equivalent to booting with vsyscall=none, except
  909. that it will also disable the helpful warning if a program
  910. tries to use a vsyscall. With this option set to N, offending
  911. programs will just segfault, citing addresses of the form
  912. 0xffffffffff600?00.
  913. This option is required by many programs built before 2013, and
  914. care should be used even with newer programs if set to N.
  915. Disabling this option saves about 7K of kernel size and
  916. possibly 4K of additional runtime pagetable memory.
  917. config TOSHIBA
  918. tristate "Toshiba Laptop support"
  919. depends on X86_32
  920. ---help---
  921. This adds a driver to safely access the System Management Mode of
  922. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  923. not work on models with a Phoenix BIOS. The System Management Mode
  924. is used to set the BIOS and power saving options on Toshiba portables.
  925. For information on utilities to make use of this driver see the
  926. Toshiba Linux utilities web site at:
  927. <http://www.buzzard.org.uk/toshiba/>.
  928. Say Y if you intend to run this kernel on a Toshiba portable.
  929. Say N otherwise.
  930. config I8K
  931. tristate "Dell i8k legacy laptop support"
  932. select HWMON
  933. select SENSORS_DELL_SMM
  934. ---help---
  935. This option enables legacy /proc/i8k userspace interface in hwmon
  936. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  937. temperature and allows controlling fan speeds of Dell laptops via
  938. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  939. it reports also power and hotkey status. For fan speed control is
  940. needed userspace package i8kutils.
  941. Say Y if you intend to run this kernel on old Dell laptops or want to
  942. use userspace package i8kutils.
  943. Say N otherwise.
  944. config X86_REBOOTFIXUPS
  945. bool "Enable X86 board specific fixups for reboot"
  946. depends on X86_32
  947. ---help---
  948. This enables chipset and/or board specific fixups to be done
  949. in order to get reboot to work correctly. This is only needed on
  950. some combinations of hardware and BIOS. The symptom, for which
  951. this config is intended, is when reboot ends with a stalled/hung
  952. system.
  953. Currently, the only fixup is for the Geode machines using
  954. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  955. Say Y if you want to enable the fixup. Currently, it's safe to
  956. enable this option even if you don't need it.
  957. Say N otherwise.
  958. config MICROCODE
  959. tristate "CPU microcode loading support"
  960. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  961. select FW_LOADER
  962. ---help---
  963. If you say Y here, you will be able to update the microcode on
  964. certain Intel and AMD processors. The Intel support is for the
  965. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
  966. Xeon etc. The AMD support is for families 0x10 and later. You will
  967. obviously need the actual microcode binary data itself which is not
  968. shipped with the Linux kernel.
  969. This option selects the general module only, you need to select
  970. at least one vendor specific module as well.
  971. To compile this driver as a module, choose M here: the module
  972. will be called microcode.
  973. config MICROCODE_INTEL
  974. bool "Intel microcode loading support"
  975. depends on MICROCODE
  976. default MICROCODE
  977. select FW_LOADER
  978. ---help---
  979. This options enables microcode patch loading support for Intel
  980. processors.
  981. For the current Intel microcode data package go to
  982. <https://downloadcenter.intel.com> and search for
  983. 'Linux Processor Microcode Data File'.
  984. config MICROCODE_AMD
  985. bool "AMD microcode loading support"
  986. depends on MICROCODE
  987. select FW_LOADER
  988. ---help---
  989. If you select this option, microcode patch loading support for AMD
  990. processors will be enabled.
  991. config MICROCODE_OLD_INTERFACE
  992. def_bool y
  993. depends on MICROCODE
  994. config MICROCODE_INTEL_EARLY
  995. bool
  996. config MICROCODE_AMD_EARLY
  997. bool
  998. config MICROCODE_EARLY
  999. bool "Early load microcode"
  1000. depends on MICROCODE=y && BLK_DEV_INITRD
  1001. select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
  1002. select MICROCODE_AMD_EARLY if MICROCODE_AMD
  1003. default y
  1004. help
  1005. This option provides functionality to read additional microcode data
  1006. at the beginning of initrd image. The data tells kernel to load
  1007. microcode to CPU's as early as possible. No functional change if no
  1008. microcode data is glued to the initrd, therefore it's safe to say Y.
  1009. config X86_MSR
  1010. tristate "/dev/cpu/*/msr - Model-specific register support"
  1011. ---help---
  1012. This device gives privileged processes access to the x86
  1013. Model-Specific Registers (MSRs). It is a character device with
  1014. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1015. MSR accesses are directed to a specific CPU on multi-processor
  1016. systems.
  1017. config X86_CPUID
  1018. tristate "/dev/cpu/*/cpuid - CPU information support"
  1019. ---help---
  1020. This device gives processes access to the x86 CPUID instruction to
  1021. be executed on a specific processor. It is a character device
  1022. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1023. /dev/cpu/31/cpuid.
  1024. choice
  1025. prompt "High Memory Support"
  1026. default HIGHMEM4G
  1027. depends on X86_32
  1028. config NOHIGHMEM
  1029. bool "off"
  1030. ---help---
  1031. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1032. However, the address space of 32-bit x86 processors is only 4
  1033. Gigabytes large. That means that, if you have a large amount of
  1034. physical memory, not all of it can be "permanently mapped" by the
  1035. kernel. The physical memory that's not permanently mapped is called
  1036. "high memory".
  1037. If you are compiling a kernel which will never run on a machine with
  1038. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1039. choice and suitable for most users). This will result in a "3GB/1GB"
  1040. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1041. space and the remaining part of the 4GB virtual memory space is used
  1042. by the kernel to permanently map as much physical memory as
  1043. possible.
  1044. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1045. answer "4GB" here.
  1046. If more than 4 Gigabytes is used then answer "64GB" here. This
  1047. selection turns Intel PAE (Physical Address Extension) mode on.
  1048. PAE implements 3-level paging on IA32 processors. PAE is fully
  1049. supported by Linux, PAE mode is implemented on all recent Intel
  1050. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1051. then the kernel will not boot on CPUs that don't support PAE!
  1052. The actual amount of total physical memory will either be
  1053. auto detected or can be forced by using a kernel command line option
  1054. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1055. your boot loader (lilo or loadlin) about how to pass options to the
  1056. kernel at boot time.)
  1057. If unsure, say "off".
  1058. config HIGHMEM4G
  1059. bool "4GB"
  1060. ---help---
  1061. Select this if you have a 32-bit processor and between 1 and 4
  1062. gigabytes of physical RAM.
  1063. config HIGHMEM64G
  1064. bool "64GB"
  1065. depends on !M486
  1066. select X86_PAE
  1067. ---help---
  1068. Select this if you have a 32-bit processor and more than 4
  1069. gigabytes of physical RAM.
  1070. endchoice
  1071. choice
  1072. prompt "Memory split" if EXPERT
  1073. default VMSPLIT_3G
  1074. depends on X86_32
  1075. ---help---
  1076. Select the desired split between kernel and user memory.
  1077. If the address range available to the kernel is less than the
  1078. physical memory installed, the remaining memory will be available
  1079. as "high memory". Accessing high memory is a little more costly
  1080. than low memory, as it needs to be mapped into the kernel first.
  1081. Note that increasing the kernel address space limits the range
  1082. available to user programs, making the address space there
  1083. tighter. Selecting anything other than the default 3G/1G split
  1084. will also likely make your kernel incompatible with binary-only
  1085. kernel modules.
  1086. If you are not absolutely sure what you are doing, leave this
  1087. option alone!
  1088. config VMSPLIT_3G
  1089. bool "3G/1G user/kernel split"
  1090. config VMSPLIT_3G_OPT
  1091. depends on !X86_PAE
  1092. bool "3G/1G user/kernel split (for full 1G low memory)"
  1093. config VMSPLIT_2G
  1094. bool "2G/2G user/kernel split"
  1095. config VMSPLIT_2G_OPT
  1096. depends on !X86_PAE
  1097. bool "2G/2G user/kernel split (for full 2G low memory)"
  1098. config VMSPLIT_1G
  1099. bool "1G/3G user/kernel split"
  1100. endchoice
  1101. config PAGE_OFFSET
  1102. hex
  1103. default 0xB0000000 if VMSPLIT_3G_OPT
  1104. default 0x80000000 if VMSPLIT_2G
  1105. default 0x78000000 if VMSPLIT_2G_OPT
  1106. default 0x40000000 if VMSPLIT_1G
  1107. default 0xC0000000
  1108. depends on X86_32
  1109. config HIGHMEM
  1110. def_bool y
  1111. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1112. config X86_PAE
  1113. bool "PAE (Physical Address Extension) Support"
  1114. depends on X86_32 && !HIGHMEM4G
  1115. ---help---
  1116. PAE is required for NX support, and furthermore enables
  1117. larger swapspace support for non-overcommit purposes. It
  1118. has the cost of more pagetable lookup overhead, and also
  1119. consumes more pagetable space per process.
  1120. config ARCH_PHYS_ADDR_T_64BIT
  1121. def_bool y
  1122. depends on X86_64 || X86_PAE
  1123. config ARCH_DMA_ADDR_T_64BIT
  1124. def_bool y
  1125. depends on X86_64 || HIGHMEM64G
  1126. config X86_DIRECT_GBPAGES
  1127. def_bool y
  1128. depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
  1129. ---help---
  1130. Certain kernel features effectively disable kernel
  1131. linear 1 GB mappings (even if the CPU otherwise
  1132. supports them), so don't confuse the user by printing
  1133. that we have them enabled.
  1134. # Common NUMA Features
  1135. config NUMA
  1136. bool "Numa Memory Allocation and Scheduler Support"
  1137. depends on SMP
  1138. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1139. default y if X86_BIGSMP
  1140. ---help---
  1141. Enable NUMA (Non Uniform Memory Access) support.
  1142. The kernel will try to allocate memory used by a CPU on the
  1143. local memory controller of the CPU and add some more
  1144. NUMA awareness to the kernel.
  1145. For 64-bit this is recommended if the system is Intel Core i7
  1146. (or later), AMD Opteron, or EM64T NUMA.
  1147. For 32-bit this is only needed if you boot a 32-bit
  1148. kernel on a 64-bit NUMA platform.
  1149. Otherwise, you should say N.
  1150. config AMD_NUMA
  1151. def_bool y
  1152. prompt "Old style AMD Opteron NUMA detection"
  1153. depends on X86_64 && NUMA && PCI
  1154. ---help---
  1155. Enable AMD NUMA node topology detection. You should say Y here if
  1156. you have a multi processor AMD system. This uses an old method to
  1157. read the NUMA configuration directly from the builtin Northbridge
  1158. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1159. which also takes priority if both are compiled in.
  1160. config X86_64_ACPI_NUMA
  1161. def_bool y
  1162. prompt "ACPI NUMA detection"
  1163. depends on X86_64 && NUMA && ACPI && PCI
  1164. select ACPI_NUMA
  1165. ---help---
  1166. Enable ACPI SRAT based node topology detection.
  1167. # Some NUMA nodes have memory ranges that span
  1168. # other nodes. Even though a pfn is valid and
  1169. # between a node's start and end pfns, it may not
  1170. # reside on that node. See memmap_init_zone()
  1171. # for details.
  1172. config NODES_SPAN_OTHER_NODES
  1173. def_bool y
  1174. depends on X86_64_ACPI_NUMA
  1175. config NUMA_EMU
  1176. bool "NUMA emulation"
  1177. depends on NUMA
  1178. ---help---
  1179. Enable NUMA emulation. A flat machine will be split
  1180. into virtual nodes when booted with "numa=fake=N", where N is the
  1181. number of nodes. This is only useful for debugging.
  1182. config NODES_SHIFT
  1183. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1184. range 1 10
  1185. default "10" if MAXSMP
  1186. default "6" if X86_64
  1187. default "3"
  1188. depends on NEED_MULTIPLE_NODES
  1189. ---help---
  1190. Specify the maximum number of NUMA Nodes available on the target
  1191. system. Increases memory reserved to accommodate various tables.
  1192. config ARCH_HAVE_MEMORY_PRESENT
  1193. def_bool y
  1194. depends on X86_32 && DISCONTIGMEM
  1195. config NEED_NODE_MEMMAP_SIZE
  1196. def_bool y
  1197. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1198. config ARCH_FLATMEM_ENABLE
  1199. def_bool y
  1200. depends on X86_32 && !NUMA
  1201. config ARCH_DISCONTIGMEM_ENABLE
  1202. def_bool y
  1203. depends on NUMA && X86_32
  1204. config ARCH_DISCONTIGMEM_DEFAULT
  1205. def_bool y
  1206. depends on NUMA && X86_32
  1207. config ARCH_SPARSEMEM_ENABLE
  1208. def_bool y
  1209. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1210. select SPARSEMEM_STATIC if X86_32
  1211. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1212. config ARCH_SPARSEMEM_DEFAULT
  1213. def_bool y
  1214. depends on X86_64
  1215. config ARCH_SELECT_MEMORY_MODEL
  1216. def_bool y
  1217. depends on ARCH_SPARSEMEM_ENABLE
  1218. config ARCH_MEMORY_PROBE
  1219. bool "Enable sysfs memory/probe interface"
  1220. depends on X86_64 && MEMORY_HOTPLUG
  1221. help
  1222. This option enables a sysfs memory/probe interface for testing.
  1223. See Documentation/memory-hotplug.txt for more information.
  1224. If you are unsure how to answer this question, answer N.
  1225. config ARCH_PROC_KCORE_TEXT
  1226. def_bool y
  1227. depends on X86_64 && PROC_KCORE
  1228. config ILLEGAL_POINTER_VALUE
  1229. hex
  1230. default 0 if X86_32
  1231. default 0xdead000000000000 if X86_64
  1232. source "mm/Kconfig"
  1233. config X86_PMEM_LEGACY_DEVICE
  1234. bool
  1235. config X86_PMEM_LEGACY
  1236. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1237. depends on PHYS_ADDR_T_64BIT
  1238. depends on BLK_DEV
  1239. select X86_PMEM_LEGACY_DEVICE
  1240. select LIBNVDIMM
  1241. help
  1242. Treat memory marked using the non-standard e820 type of 12 as used
  1243. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1244. The kernel will offer these regions to the 'pmem' driver so
  1245. they can be used for persistent storage.
  1246. Say Y if unsure.
  1247. config HIGHPTE
  1248. bool "Allocate 3rd-level pagetables from highmem"
  1249. depends on HIGHMEM
  1250. ---help---
  1251. The VM uses one page table entry for each page of physical memory.
  1252. For systems with a lot of RAM, this can be wasteful of precious
  1253. low memory. Setting this option will put user-space page table
  1254. entries in high memory.
  1255. config X86_CHECK_BIOS_CORRUPTION
  1256. bool "Check for low memory corruption"
  1257. ---help---
  1258. Periodically check for memory corruption in low memory, which
  1259. is suspected to be caused by BIOS. Even when enabled in the
  1260. configuration, it is disabled at runtime. Enable it by
  1261. setting "memory_corruption_check=1" on the kernel command
  1262. line. By default it scans the low 64k of memory every 60
  1263. seconds; see the memory_corruption_check_size and
  1264. memory_corruption_check_period parameters in
  1265. Documentation/kernel-parameters.txt to adjust this.
  1266. When enabled with the default parameters, this option has
  1267. almost no overhead, as it reserves a relatively small amount
  1268. of memory and scans it infrequently. It both detects corruption
  1269. and prevents it from affecting the running system.
  1270. It is, however, intended as a diagnostic tool; if repeatable
  1271. BIOS-originated corruption always affects the same memory,
  1272. you can use memmap= to prevent the kernel from using that
  1273. memory.
  1274. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1275. bool "Set the default setting of memory_corruption_check"
  1276. depends on X86_CHECK_BIOS_CORRUPTION
  1277. default y
  1278. ---help---
  1279. Set whether the default state of memory_corruption_check is
  1280. on or off.
  1281. config X86_RESERVE_LOW
  1282. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1283. default 64
  1284. range 4 640
  1285. ---help---
  1286. Specify the amount of low memory to reserve for the BIOS.
  1287. The first page contains BIOS data structures that the kernel
  1288. must not use, so that page must always be reserved.
  1289. By default we reserve the first 64K of physical RAM, as a
  1290. number of BIOSes are known to corrupt that memory range
  1291. during events such as suspend/resume or monitor cable
  1292. insertion, so it must not be used by the kernel.
  1293. You can set this to 4 if you are absolutely sure that you
  1294. trust the BIOS to get all its memory reservations and usages
  1295. right. If you know your BIOS have problems beyond the
  1296. default 64K area, you can set this to 640 to avoid using the
  1297. entire low memory range.
  1298. If you have doubts about the BIOS (e.g. suspend/resume does
  1299. not work or there's kernel crashes after certain hardware
  1300. hotplug events) then you might want to enable
  1301. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1302. typical corruption patterns.
  1303. Leave this to the default value of 64 if you are unsure.
  1304. config MATH_EMULATION
  1305. bool
  1306. depends on MODIFY_LDT_SYSCALL
  1307. prompt "Math emulation" if X86_32
  1308. ---help---
  1309. Linux can emulate a math coprocessor (used for floating point
  1310. operations) if you don't have one. 486DX and Pentium processors have
  1311. a math coprocessor built in, 486SX and 386 do not, unless you added
  1312. a 487DX or 387, respectively. (The messages during boot time can
  1313. give you some hints here ["man dmesg"].) Everyone needs either a
  1314. coprocessor or this emulation.
  1315. If you don't have a math coprocessor, you need to say Y here; if you
  1316. say Y here even though you have a coprocessor, the coprocessor will
  1317. be used nevertheless. (This behavior can be changed with the kernel
  1318. command line option "no387", which comes handy if your coprocessor
  1319. is broken. Try "man bootparam" or see the documentation of your boot
  1320. loader (lilo or loadlin) about how to pass options to the kernel at
  1321. boot time.) This means that it is a good idea to say Y here if you
  1322. intend to use this kernel on different machines.
  1323. More information about the internals of the Linux math coprocessor
  1324. emulation can be found in <file:arch/x86/math-emu/README>.
  1325. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1326. kernel, it won't hurt.
  1327. config MTRR
  1328. def_bool y
  1329. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1330. ---help---
  1331. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1332. the Memory Type Range Registers (MTRRs) may be used to control
  1333. processor access to memory ranges. This is most useful if you have
  1334. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1335. allows bus write transfers to be combined into a larger transfer
  1336. before bursting over the PCI/AGP bus. This can increase performance
  1337. of image write operations 2.5 times or more. Saying Y here creates a
  1338. /proc/mtrr file which may be used to manipulate your processor's
  1339. MTRRs. Typically the X server should use this.
  1340. This code has a reasonably generic interface so that similar
  1341. control registers on other processors can be easily supported
  1342. as well:
  1343. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1344. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1345. these, the ARRs are used to emulate the MTRRs.
  1346. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1347. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1348. write-combining. All of these processors are supported by this code
  1349. and it makes sense to say Y here if you have one of them.
  1350. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1351. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1352. can lead to all sorts of problems, so it's good to say Y here.
  1353. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1354. just add about 9 KB to your kernel.
  1355. See <file:Documentation/x86/mtrr.txt> for more information.
  1356. config MTRR_SANITIZER
  1357. def_bool y
  1358. prompt "MTRR cleanup support"
  1359. depends on MTRR
  1360. ---help---
  1361. Convert MTRR layout from continuous to discrete, so X drivers can
  1362. add writeback entries.
  1363. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1364. The largest mtrr entry size for a continuous block can be set with
  1365. mtrr_chunk_size.
  1366. If unsure, say Y.
  1367. config MTRR_SANITIZER_ENABLE_DEFAULT
  1368. int "MTRR cleanup enable value (0-1)"
  1369. range 0 1
  1370. default "0"
  1371. depends on MTRR_SANITIZER
  1372. ---help---
  1373. Enable mtrr cleanup default value
  1374. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1375. int "MTRR cleanup spare reg num (0-7)"
  1376. range 0 7
  1377. default "1"
  1378. depends on MTRR_SANITIZER
  1379. ---help---
  1380. mtrr cleanup spare entries default, it can be changed via
  1381. mtrr_spare_reg_nr=N on the kernel command line.
  1382. config X86_PAT
  1383. def_bool y
  1384. prompt "x86 PAT support" if EXPERT
  1385. depends on MTRR
  1386. ---help---
  1387. Use PAT attributes to setup page level cache control.
  1388. PATs are the modern equivalents of MTRRs and are much more
  1389. flexible than MTRRs.
  1390. Say N here if you see bootup problems (boot crash, boot hang,
  1391. spontaneous reboots) or a non-working video driver.
  1392. If unsure, say Y.
  1393. config ARCH_USES_PG_UNCACHED
  1394. def_bool y
  1395. depends on X86_PAT
  1396. config ARCH_RANDOM
  1397. def_bool y
  1398. prompt "x86 architectural random number generator" if EXPERT
  1399. ---help---
  1400. Enable the x86 architectural RDRAND instruction
  1401. (Intel Bull Mountain technology) to generate random numbers.
  1402. If supported, this is a high bandwidth, cryptographically
  1403. secure hardware random number generator.
  1404. config X86_SMAP
  1405. def_bool y
  1406. prompt "Supervisor Mode Access Prevention" if EXPERT
  1407. ---help---
  1408. Supervisor Mode Access Prevention (SMAP) is a security
  1409. feature in newer Intel processors. There is a small
  1410. performance cost if this enabled and turned on; there is
  1411. also a small increase in the kernel size if this is enabled.
  1412. If unsure, say Y.
  1413. config X86_INTEL_MPX
  1414. prompt "Intel MPX (Memory Protection Extensions)"
  1415. def_bool n
  1416. depends on CPU_SUP_INTEL
  1417. ---help---
  1418. MPX provides hardware features that can be used in
  1419. conjunction with compiler-instrumented code to check
  1420. memory references. It is designed to detect buffer
  1421. overflow or underflow bugs.
  1422. This option enables running applications which are
  1423. instrumented or otherwise use MPX. It does not use MPX
  1424. itself inside the kernel or to protect the kernel
  1425. against bad memory references.
  1426. Enabling this option will make the kernel larger:
  1427. ~8k of kernel text and 36 bytes of data on a 64-bit
  1428. defconfig. It adds a long to the 'mm_struct' which
  1429. will increase the kernel memory overhead of each
  1430. process and adds some branches to paths used during
  1431. exec() and munmap().
  1432. For details, see Documentation/x86/intel_mpx.txt
  1433. If unsure, say N.
  1434. config EFI
  1435. bool "EFI runtime service support"
  1436. depends on ACPI
  1437. select UCS2_STRING
  1438. select EFI_RUNTIME_WRAPPERS
  1439. ---help---
  1440. This enables the kernel to use EFI runtime services that are
  1441. available (such as the EFI variable services).
  1442. This option is only useful on systems that have EFI firmware.
  1443. In addition, you should use the latest ELILO loader available
  1444. at <http://elilo.sourceforge.net> in order to take advantage
  1445. of EFI runtime services. However, even with this option, the
  1446. resultant kernel should continue to boot on existing non-EFI
  1447. platforms.
  1448. config EFI_STUB
  1449. bool "EFI stub support"
  1450. depends on EFI && !X86_USE_3DNOW
  1451. select RELOCATABLE
  1452. ---help---
  1453. This kernel feature allows a bzImage to be loaded directly
  1454. by EFI firmware without the use of a bootloader.
  1455. See Documentation/efi-stub.txt for more information.
  1456. config EFI_MIXED
  1457. bool "EFI mixed-mode support"
  1458. depends on EFI_STUB && X86_64
  1459. ---help---
  1460. Enabling this feature allows a 64-bit kernel to be booted
  1461. on a 32-bit firmware, provided that your CPU supports 64-bit
  1462. mode.
  1463. Note that it is not possible to boot a mixed-mode enabled
  1464. kernel via the EFI boot stub - a bootloader that supports
  1465. the EFI handover protocol must be used.
  1466. If unsure, say N.
  1467. config SECCOMP
  1468. def_bool y
  1469. prompt "Enable seccomp to safely compute untrusted bytecode"
  1470. ---help---
  1471. This kernel feature is useful for number crunching applications
  1472. that may need to compute untrusted bytecode during their
  1473. execution. By using pipes or other transports made available to
  1474. the process as file descriptors supporting the read/write
  1475. syscalls, it's possible to isolate those applications in
  1476. their own address space using seccomp. Once seccomp is
  1477. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1478. and the task is only allowed to execute a few safe syscalls
  1479. defined by each seccomp mode.
  1480. If unsure, say Y. Only embedded should say N here.
  1481. source kernel/Kconfig.hz
  1482. config KEXEC
  1483. bool "kexec system call"
  1484. select KEXEC_CORE
  1485. ---help---
  1486. kexec is a system call that implements the ability to shutdown your
  1487. current kernel, and to start another kernel. It is like a reboot
  1488. but it is independent of the system firmware. And like a reboot
  1489. you can start any kernel with it, not just Linux.
  1490. The name comes from the similarity to the exec system call.
  1491. It is an ongoing process to be certain the hardware in a machine
  1492. is properly shutdown, so do not be surprised if this code does not
  1493. initially work for you. As of this writing the exact hardware
  1494. interface is strongly in flux, so no good recommendation can be
  1495. made.
  1496. config KEXEC_FILE
  1497. bool "kexec file based system call"
  1498. select KEXEC_CORE
  1499. select BUILD_BIN2C
  1500. depends on X86_64
  1501. depends on CRYPTO=y
  1502. depends on CRYPTO_SHA256=y
  1503. ---help---
  1504. This is new version of kexec system call. This system call is
  1505. file based and takes file descriptors as system call argument
  1506. for kernel and initramfs as opposed to list of segments as
  1507. accepted by previous system call.
  1508. config KEXEC_VERIFY_SIG
  1509. bool "Verify kernel signature during kexec_file_load() syscall"
  1510. depends on KEXEC_FILE
  1511. ---help---
  1512. This option makes kernel signature verification mandatory for
  1513. the kexec_file_load() syscall.
  1514. In addition to that option, you need to enable signature
  1515. verification for the corresponding kernel image type being
  1516. loaded in order for this to work.
  1517. config KEXEC_BZIMAGE_VERIFY_SIG
  1518. bool "Enable bzImage signature verification support"
  1519. depends on KEXEC_VERIFY_SIG
  1520. depends on SIGNED_PE_FILE_VERIFICATION
  1521. select SYSTEM_TRUSTED_KEYRING
  1522. ---help---
  1523. Enable bzImage signature verification support.
  1524. config CRASH_DUMP
  1525. bool "kernel crash dumps"
  1526. depends on X86_64 || (X86_32 && HIGHMEM)
  1527. ---help---
  1528. Generate crash dump after being started by kexec.
  1529. This should be normally only set in special crash dump kernels
  1530. which are loaded in the main kernel with kexec-tools into
  1531. a specially reserved region and then later executed after
  1532. a crash by kdump/kexec. The crash dump kernel must be compiled
  1533. to a memory address not used by the main kernel or BIOS using
  1534. PHYSICAL_START, or it must be built as a relocatable image
  1535. (CONFIG_RELOCATABLE=y).
  1536. For more details see Documentation/kdump/kdump.txt
  1537. config KEXEC_JUMP
  1538. bool "kexec jump"
  1539. depends on KEXEC && HIBERNATION
  1540. ---help---
  1541. Jump between original kernel and kexeced kernel and invoke
  1542. code in physical address mode via KEXEC
  1543. config PHYSICAL_START
  1544. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1545. default "0x1000000"
  1546. ---help---
  1547. This gives the physical address where the kernel is loaded.
  1548. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1549. bzImage will decompress itself to above physical address and
  1550. run from there. Otherwise, bzImage will run from the address where
  1551. it has been loaded by the boot loader and will ignore above physical
  1552. address.
  1553. In normal kdump cases one does not have to set/change this option
  1554. as now bzImage can be compiled as a completely relocatable image
  1555. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1556. address. This option is mainly useful for the folks who don't want
  1557. to use a bzImage for capturing the crash dump and want to use a
  1558. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1559. to be specifically compiled to run from a specific memory area
  1560. (normally a reserved region) and this option comes handy.
  1561. So if you are using bzImage for capturing the crash dump,
  1562. leave the value here unchanged to 0x1000000 and set
  1563. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1564. for capturing the crash dump change this value to start of
  1565. the reserved region. In other words, it can be set based on
  1566. the "X" value as specified in the "crashkernel=YM@XM"
  1567. command line boot parameter passed to the panic-ed
  1568. kernel. Please take a look at Documentation/kdump/kdump.txt
  1569. for more details about crash dumps.
  1570. Usage of bzImage for capturing the crash dump is recommended as
  1571. one does not have to build two kernels. Same kernel can be used
  1572. as production kernel and capture kernel. Above option should have
  1573. gone away after relocatable bzImage support is introduced. But it
  1574. is present because there are users out there who continue to use
  1575. vmlinux for dump capture. This option should go away down the
  1576. line.
  1577. Don't change this unless you know what you are doing.
  1578. config RELOCATABLE
  1579. bool "Build a relocatable kernel"
  1580. default y
  1581. ---help---
  1582. This builds a kernel image that retains relocation information
  1583. so it can be loaded someplace besides the default 1MB.
  1584. The relocations tend to make the kernel binary about 10% larger,
  1585. but are discarded at runtime.
  1586. One use is for the kexec on panic case where the recovery kernel
  1587. must live at a different physical address than the primary
  1588. kernel.
  1589. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1590. it has been loaded at and the compile time physical address
  1591. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1592. config RANDOMIZE_BASE
  1593. bool "Randomize the address of the kernel image"
  1594. depends on RELOCATABLE
  1595. default n
  1596. ---help---
  1597. Randomizes the physical and virtual address at which the
  1598. kernel image is decompressed, as a security feature that
  1599. deters exploit attempts relying on knowledge of the location
  1600. of kernel internals.
  1601. Entropy is generated using the RDRAND instruction if it is
  1602. supported. If RDTSC is supported, it is used as well. If
  1603. neither RDRAND nor RDTSC are supported, then randomness is
  1604. read from the i8254 timer.
  1605. The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
  1606. and aligned according to PHYSICAL_ALIGN. Since the kernel is
  1607. built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
  1608. minimum of 2MiB, only 10 bits of entropy is theoretically
  1609. possible. At best, due to page table layouts, 64-bit can use
  1610. 9 bits of entropy and 32-bit uses 8 bits.
  1611. If unsure, say N.
  1612. config RANDOMIZE_BASE_MAX_OFFSET
  1613. hex "Maximum kASLR offset allowed" if EXPERT
  1614. depends on RANDOMIZE_BASE
  1615. range 0x0 0x20000000 if X86_32
  1616. default "0x20000000" if X86_32
  1617. range 0x0 0x40000000 if X86_64
  1618. default "0x40000000" if X86_64
  1619. ---help---
  1620. The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
  1621. memory is used to determine the maximal offset in bytes that will
  1622. be applied to the kernel when kernel Address Space Layout
  1623. Randomization (kASLR) is active. This must be a multiple of
  1624. PHYSICAL_ALIGN.
  1625. On 32-bit this is limited to 512MiB by page table layouts. The
  1626. default is 512MiB.
  1627. On 64-bit this is limited by how the kernel fixmap page table is
  1628. positioned, so this cannot be larger than 1GiB currently. Without
  1629. RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
  1630. and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
  1631. modules area will shrink to compensate, up to the current maximum
  1632. 1GiB to 1GiB split. The default is 1GiB.
  1633. If unsure, leave at the default value.
  1634. # Relocation on x86 needs some additional build support
  1635. config X86_NEED_RELOCS
  1636. def_bool y
  1637. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1638. config PHYSICAL_ALIGN
  1639. hex "Alignment value to which kernel should be aligned"
  1640. default "0x200000"
  1641. range 0x2000 0x1000000 if X86_32
  1642. range 0x200000 0x1000000 if X86_64
  1643. ---help---
  1644. This value puts the alignment restrictions on physical address
  1645. where kernel is loaded and run from. Kernel is compiled for an
  1646. address which meets above alignment restriction.
  1647. If bootloader loads the kernel at a non-aligned address and
  1648. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1649. address aligned to above value and run from there.
  1650. If bootloader loads the kernel at a non-aligned address and
  1651. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1652. load address and decompress itself to the address it has been
  1653. compiled for and run from there. The address for which kernel is
  1654. compiled already meets above alignment restrictions. Hence the
  1655. end result is that kernel runs from a physical address meeting
  1656. above alignment restrictions.
  1657. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1658. this value must be a multiple of 0x200000.
  1659. Don't change this unless you know what you are doing.
  1660. config HOTPLUG_CPU
  1661. bool "Support for hot-pluggable CPUs"
  1662. depends on SMP
  1663. ---help---
  1664. Say Y here to allow turning CPUs off and on. CPUs can be
  1665. controlled through /sys/devices/system/cpu.
  1666. ( Note: power management support will enable this option
  1667. automatically on SMP systems. )
  1668. Say N if you want to disable CPU hotplug.
  1669. config BOOTPARAM_HOTPLUG_CPU0
  1670. bool "Set default setting of cpu0_hotpluggable"
  1671. default n
  1672. depends on HOTPLUG_CPU
  1673. ---help---
  1674. Set whether default state of cpu0_hotpluggable is on or off.
  1675. Say Y here to enable CPU0 hotplug by default. If this switch
  1676. is turned on, there is no need to give cpu0_hotplug kernel
  1677. parameter and the CPU0 hotplug feature is enabled by default.
  1678. Please note: there are two known CPU0 dependencies if you want
  1679. to enable the CPU0 hotplug feature either by this switch or by
  1680. cpu0_hotplug kernel parameter.
  1681. First, resume from hibernate or suspend always starts from CPU0.
  1682. So hibernate and suspend are prevented if CPU0 is offline.
  1683. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1684. offline if any interrupt can not migrate out of CPU0. There may
  1685. be other CPU0 dependencies.
  1686. Please make sure the dependencies are under your control before
  1687. you enable this feature.
  1688. Say N if you don't want to enable CPU0 hotplug feature by default.
  1689. You still can enable the CPU0 hotplug feature at boot by kernel
  1690. parameter cpu0_hotplug.
  1691. config DEBUG_HOTPLUG_CPU0
  1692. def_bool n
  1693. prompt "Debug CPU0 hotplug"
  1694. depends on HOTPLUG_CPU
  1695. ---help---
  1696. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1697. soon as possible and boots up userspace with CPU0 offlined. User
  1698. can online CPU0 back after boot time.
  1699. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1700. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1701. compilation or giving cpu0_hotplug kernel parameter at boot.
  1702. If unsure, say N.
  1703. config COMPAT_VDSO
  1704. def_bool n
  1705. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1706. depends on X86_32 || IA32_EMULATION
  1707. ---help---
  1708. Certain buggy versions of glibc will crash if they are
  1709. presented with a 32-bit vDSO that is not mapped at the address
  1710. indicated in its segment table.
  1711. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1712. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1713. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1714. the only released version with the bug, but OpenSUSE 9
  1715. contains a buggy "glibc 2.3.2".
  1716. The symptom of the bug is that everything crashes on startup, saying:
  1717. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1718. Saying Y here changes the default value of the vdso32 boot
  1719. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1720. This works around the glibc bug but hurts performance.
  1721. If unsure, say N: if you are compiling your own kernel, you
  1722. are unlikely to be using a buggy version of glibc.
  1723. config CMDLINE_BOOL
  1724. bool "Built-in kernel command line"
  1725. ---help---
  1726. Allow for specifying boot arguments to the kernel at
  1727. build time. On some systems (e.g. embedded ones), it is
  1728. necessary or convenient to provide some or all of the
  1729. kernel boot arguments with the kernel itself (that is,
  1730. to not rely on the boot loader to provide them.)
  1731. To compile command line arguments into the kernel,
  1732. set this option to 'Y', then fill in the
  1733. boot arguments in CONFIG_CMDLINE.
  1734. Systems with fully functional boot loaders (i.e. non-embedded)
  1735. should leave this option set to 'N'.
  1736. config CMDLINE
  1737. string "Built-in kernel command string"
  1738. depends on CMDLINE_BOOL
  1739. default ""
  1740. ---help---
  1741. Enter arguments here that should be compiled into the kernel
  1742. image and used at boot time. If the boot loader provides a
  1743. command line at boot time, it is appended to this string to
  1744. form the full kernel command line, when the system boots.
  1745. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1746. change this behavior.
  1747. In most cases, the command line (whether built-in or provided
  1748. by the boot loader) should specify the device for the root
  1749. file system.
  1750. config CMDLINE_OVERRIDE
  1751. bool "Built-in command line overrides boot loader arguments"
  1752. depends on CMDLINE_BOOL
  1753. ---help---
  1754. Set this option to 'Y' to have the kernel ignore the boot loader
  1755. command line, and use ONLY the built-in command line.
  1756. This is used to work around broken boot loaders. This should
  1757. be set to 'N' under normal conditions.
  1758. config MODIFY_LDT_SYSCALL
  1759. bool "Enable the LDT (local descriptor table)" if EXPERT
  1760. default y
  1761. ---help---
  1762. Linux can allow user programs to install a per-process x86
  1763. Local Descriptor Table (LDT) using the modify_ldt(2) system
  1764. call. This is required to run 16-bit or segmented code such as
  1765. DOSEMU or some Wine programs. It is also used by some very old
  1766. threading libraries.
  1767. Enabling this feature adds a small amount of overhead to
  1768. context switches and increases the low-level kernel attack
  1769. surface. Disabling it removes the modify_ldt(2) system call.
  1770. Saying 'N' here may make sense for embedded or server kernels.
  1771. source "kernel/livepatch/Kconfig"
  1772. endmenu
  1773. config ARCH_ENABLE_MEMORY_HOTPLUG
  1774. def_bool y
  1775. depends on X86_64 || (X86_32 && HIGHMEM)
  1776. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1777. def_bool y
  1778. depends on MEMORY_HOTPLUG
  1779. config USE_PERCPU_NUMA_NODE_ID
  1780. def_bool y
  1781. depends on NUMA
  1782. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  1783. def_bool y
  1784. depends on X86_64 || X86_PAE
  1785. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  1786. def_bool y
  1787. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  1788. menu "Power management and ACPI options"
  1789. config ARCH_HIBERNATION_HEADER
  1790. def_bool y
  1791. depends on X86_64 && HIBERNATION
  1792. source "kernel/power/Kconfig"
  1793. source "drivers/acpi/Kconfig"
  1794. source "drivers/sfi/Kconfig"
  1795. config X86_APM_BOOT
  1796. def_bool y
  1797. depends on APM
  1798. menuconfig APM
  1799. tristate "APM (Advanced Power Management) BIOS support"
  1800. depends on X86_32 && PM_SLEEP
  1801. ---help---
  1802. APM is a BIOS specification for saving power using several different
  1803. techniques. This is mostly useful for battery powered laptops with
  1804. APM compliant BIOSes. If you say Y here, the system time will be
  1805. reset after a RESUME operation, the /proc/apm device will provide
  1806. battery status information, and user-space programs will receive
  1807. notification of APM "events" (e.g. battery status change).
  1808. If you select "Y" here, you can disable actual use of the APM
  1809. BIOS by passing the "apm=off" option to the kernel at boot time.
  1810. Note that the APM support is almost completely disabled for
  1811. machines with more than one CPU.
  1812. In order to use APM, you will need supporting software. For location
  1813. and more information, read <file:Documentation/power/apm-acpi.txt>
  1814. and the Battery Powered Linux mini-HOWTO, available from
  1815. <http://www.tldp.org/docs.html#howto>.
  1816. This driver does not spin down disk drives (see the hdparm(8)
  1817. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1818. VESA-compliant "green" monitors.
  1819. This driver does not support the TI 4000M TravelMate and the ACER
  1820. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1821. desktop machines also don't have compliant BIOSes, and this driver
  1822. may cause those machines to panic during the boot phase.
  1823. Generally, if you don't have a battery in your machine, there isn't
  1824. much point in using this driver and you should say N. If you get
  1825. random kernel OOPSes or reboots that don't seem to be related to
  1826. anything, try disabling/enabling this option (or disabling/enabling
  1827. APM in your BIOS).
  1828. Some other things you should try when experiencing seemingly random,
  1829. "weird" problems:
  1830. 1) make sure that you have enough swap space and that it is
  1831. enabled.
  1832. 2) pass the "no-hlt" option to the kernel
  1833. 3) switch on floating point emulation in the kernel and pass
  1834. the "no387" option to the kernel
  1835. 4) pass the "floppy=nodma" option to the kernel
  1836. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1837. all but the first 4 MB of RAM)
  1838. 6) make sure that the CPU is not over clocked.
  1839. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1840. 8) disable the cache from your BIOS settings
  1841. 9) install a fan for the video card or exchange video RAM
  1842. 10) install a better fan for the CPU
  1843. 11) exchange RAM chips
  1844. 12) exchange the motherboard.
  1845. To compile this driver as a module, choose M here: the
  1846. module will be called apm.
  1847. if APM
  1848. config APM_IGNORE_USER_SUSPEND
  1849. bool "Ignore USER SUSPEND"
  1850. ---help---
  1851. This option will ignore USER SUSPEND requests. On machines with a
  1852. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1853. series notebooks, it is necessary to say Y because of a BIOS bug.
  1854. config APM_DO_ENABLE
  1855. bool "Enable PM at boot time"
  1856. ---help---
  1857. Enable APM features at boot time. From page 36 of the APM BIOS
  1858. specification: "When disabled, the APM BIOS does not automatically
  1859. power manage devices, enter the Standby State, enter the Suspend
  1860. State, or take power saving steps in response to CPU Idle calls."
  1861. This driver will make CPU Idle calls when Linux is idle (unless this
  1862. feature is turned off -- see "Do CPU IDLE calls", below). This
  1863. should always save battery power, but more complicated APM features
  1864. will be dependent on your BIOS implementation. You may need to turn
  1865. this option off if your computer hangs at boot time when using APM
  1866. support, or if it beeps continuously instead of suspending. Turn
  1867. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1868. T400CDT. This is off by default since most machines do fine without
  1869. this feature.
  1870. config APM_CPU_IDLE
  1871. depends on CPU_IDLE
  1872. bool "Make CPU Idle calls when idle"
  1873. ---help---
  1874. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1875. On some machines, this can activate improved power savings, such as
  1876. a slowed CPU clock rate, when the machine is idle. These idle calls
  1877. are made after the idle loop has run for some length of time (e.g.,
  1878. 333 mS). On some machines, this will cause a hang at boot time or
  1879. whenever the CPU becomes idle. (On machines with more than one CPU,
  1880. this option does nothing.)
  1881. config APM_DISPLAY_BLANK
  1882. bool "Enable console blanking using APM"
  1883. ---help---
  1884. Enable console blanking using the APM. Some laptops can use this to
  1885. turn off the LCD backlight when the screen blanker of the Linux
  1886. virtual console blanks the screen. Note that this is only used by
  1887. the virtual console screen blanker, and won't turn off the backlight
  1888. when using the X Window system. This also doesn't have anything to
  1889. do with your VESA-compliant power-saving monitor. Further, this
  1890. option doesn't work for all laptops -- it might not turn off your
  1891. backlight at all, or it might print a lot of errors to the console,
  1892. especially if you are using gpm.
  1893. config APM_ALLOW_INTS
  1894. bool "Allow interrupts during APM BIOS calls"
  1895. ---help---
  1896. Normally we disable external interrupts while we are making calls to
  1897. the APM BIOS as a measure to lessen the effects of a badly behaving
  1898. BIOS implementation. The BIOS should reenable interrupts if it
  1899. needs to. Unfortunately, some BIOSes do not -- especially those in
  1900. many of the newer IBM Thinkpads. If you experience hangs when you
  1901. suspend, try setting this to Y. Otherwise, say N.
  1902. endif # APM
  1903. source "drivers/cpufreq/Kconfig"
  1904. source "drivers/cpuidle/Kconfig"
  1905. source "drivers/idle/Kconfig"
  1906. endmenu
  1907. menu "Bus options (PCI etc.)"
  1908. config PCI
  1909. bool "PCI support"
  1910. default y
  1911. ---help---
  1912. Find out whether you have a PCI motherboard. PCI is the name of a
  1913. bus system, i.e. the way the CPU talks to the other stuff inside
  1914. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1915. VESA. If you have PCI, say Y, otherwise N.
  1916. choice
  1917. prompt "PCI access mode"
  1918. depends on X86_32 && PCI
  1919. default PCI_GOANY
  1920. ---help---
  1921. On PCI systems, the BIOS can be used to detect the PCI devices and
  1922. determine their configuration. However, some old PCI motherboards
  1923. have BIOS bugs and may crash if this is done. Also, some embedded
  1924. PCI-based systems don't have any BIOS at all. Linux can also try to
  1925. detect the PCI hardware directly without using the BIOS.
  1926. With this option, you can specify how Linux should detect the
  1927. PCI devices. If you choose "BIOS", the BIOS will be used,
  1928. if you choose "Direct", the BIOS won't be used, and if you
  1929. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1930. If you choose "Any", the kernel will try MMCONFIG, then the
  1931. direct access method and falls back to the BIOS if that doesn't
  1932. work. If unsure, go with the default, which is "Any".
  1933. config PCI_GOBIOS
  1934. bool "BIOS"
  1935. config PCI_GOMMCONFIG
  1936. bool "MMConfig"
  1937. config PCI_GODIRECT
  1938. bool "Direct"
  1939. config PCI_GOOLPC
  1940. bool "OLPC XO-1"
  1941. depends on OLPC
  1942. config PCI_GOANY
  1943. bool "Any"
  1944. endchoice
  1945. config PCI_BIOS
  1946. def_bool y
  1947. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1948. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1949. config PCI_DIRECT
  1950. def_bool y
  1951. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  1952. config PCI_MMCONFIG
  1953. def_bool y
  1954. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1955. config PCI_OLPC
  1956. def_bool y
  1957. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1958. config PCI_XEN
  1959. def_bool y
  1960. depends on PCI && XEN
  1961. select SWIOTLB_XEN
  1962. config PCI_DOMAINS
  1963. def_bool y
  1964. depends on PCI
  1965. config PCI_MMCONFIG
  1966. bool "Support mmconfig PCI config space access"
  1967. depends on X86_64 && PCI && ACPI
  1968. config PCI_CNB20LE_QUIRK
  1969. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1970. depends on PCI
  1971. help
  1972. Read the PCI windows out of the CNB20LE host bridge. This allows
  1973. PCI hotplug to work on systems with the CNB20LE chipset which do
  1974. not have ACPI.
  1975. There's no public spec for this chipset, and this functionality
  1976. is known to be incomplete.
  1977. You should say N unless you know you need this.
  1978. source "drivers/pci/pcie/Kconfig"
  1979. source "drivers/pci/Kconfig"
  1980. # x86_64 have no ISA slots, but can have ISA-style DMA.
  1981. config ISA_DMA_API
  1982. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  1983. default y
  1984. help
  1985. Enables ISA-style DMA support for devices requiring such controllers.
  1986. If unsure, say Y.
  1987. if X86_32
  1988. config ISA
  1989. bool "ISA support"
  1990. ---help---
  1991. Find out whether you have ISA slots on your motherboard. ISA is the
  1992. name of a bus system, i.e. the way the CPU talks to the other stuff
  1993. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1994. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1995. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1996. config EISA
  1997. bool "EISA support"
  1998. depends on ISA
  1999. ---help---
  2000. The Extended Industry Standard Architecture (EISA) bus was
  2001. developed as an open alternative to the IBM MicroChannel bus.
  2002. The EISA bus provided some of the features of the IBM MicroChannel
  2003. bus while maintaining backward compatibility with cards made for
  2004. the older ISA bus. The EISA bus saw limited use between 1988 and
  2005. 1995 when it was made obsolete by the PCI bus.
  2006. Say Y here if you are building a kernel for an EISA-based machine.
  2007. Otherwise, say N.
  2008. source "drivers/eisa/Kconfig"
  2009. config SCx200
  2010. tristate "NatSemi SCx200 support"
  2011. ---help---
  2012. This provides basic support for National Semiconductor's
  2013. (now AMD's) Geode processors. The driver probes for the
  2014. PCI-IDs of several on-chip devices, so its a good dependency
  2015. for other scx200_* drivers.
  2016. If compiled as a module, the driver is named scx200.
  2017. config SCx200HR_TIMER
  2018. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2019. depends on SCx200
  2020. default y
  2021. ---help---
  2022. This driver provides a clocksource built upon the on-chip
  2023. 27MHz high-resolution timer. Its also a workaround for
  2024. NSC Geode SC-1100's buggy TSC, which loses time when the
  2025. processor goes idle (as is done by the scheduler). The
  2026. other workaround is idle=poll boot option.
  2027. config OLPC
  2028. bool "One Laptop Per Child support"
  2029. depends on !X86_PAE
  2030. select GPIOLIB
  2031. select OF
  2032. select OF_PROMTREE
  2033. select IRQ_DOMAIN
  2034. ---help---
  2035. Add support for detecting the unique features of the OLPC
  2036. XO hardware.
  2037. config OLPC_XO1_PM
  2038. bool "OLPC XO-1 Power Management"
  2039. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2040. select MFD_CORE
  2041. ---help---
  2042. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2043. config OLPC_XO1_RTC
  2044. bool "OLPC XO-1 Real Time Clock"
  2045. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2046. ---help---
  2047. Add support for the XO-1 real time clock, which can be used as a
  2048. programmable wakeup source.
  2049. config OLPC_XO1_SCI
  2050. bool "OLPC XO-1 SCI extras"
  2051. depends on OLPC && OLPC_XO1_PM
  2052. depends on INPUT=y
  2053. select POWER_SUPPLY
  2054. select GPIO_CS5535
  2055. select MFD_CORE
  2056. ---help---
  2057. Add support for SCI-based features of the OLPC XO-1 laptop:
  2058. - EC-driven system wakeups
  2059. - Power button
  2060. - Ebook switch
  2061. - Lid switch
  2062. - AC adapter status updates
  2063. - Battery status updates
  2064. config OLPC_XO15_SCI
  2065. bool "OLPC XO-1.5 SCI extras"
  2066. depends on OLPC && ACPI
  2067. select POWER_SUPPLY
  2068. ---help---
  2069. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2070. - EC-driven system wakeups
  2071. - AC adapter status updates
  2072. - Battery status updates
  2073. config ALIX
  2074. bool "PCEngines ALIX System Support (LED setup)"
  2075. select GPIOLIB
  2076. ---help---
  2077. This option enables system support for the PCEngines ALIX.
  2078. At present this just sets up LEDs for GPIO control on
  2079. ALIX2/3/6 boards. However, other system specific setup should
  2080. get added here.
  2081. Note: You must still enable the drivers for GPIO and LED support
  2082. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2083. Note: You have to set alix.force=1 for boards with Award BIOS.
  2084. config NET5501
  2085. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2086. select GPIOLIB
  2087. ---help---
  2088. This option enables system support for the Soekris Engineering net5501.
  2089. config GEOS
  2090. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2091. select GPIOLIB
  2092. depends on DMI
  2093. ---help---
  2094. This option enables system support for the Traverse Technologies GEOS.
  2095. config TS5500
  2096. bool "Technologic Systems TS-5500 platform support"
  2097. depends on MELAN
  2098. select CHECK_SIGNATURE
  2099. select NEW_LEDS
  2100. select LEDS_CLASS
  2101. ---help---
  2102. This option enables system support for the Technologic Systems TS-5500.
  2103. endif # X86_32
  2104. config AMD_NB
  2105. def_bool y
  2106. depends on CPU_SUP_AMD && PCI
  2107. source "drivers/pcmcia/Kconfig"
  2108. source "drivers/pci/hotplug/Kconfig"
  2109. config RAPIDIO
  2110. tristate "RapidIO support"
  2111. depends on PCI
  2112. default n
  2113. help
  2114. If enabled this option will include drivers and the core
  2115. infrastructure code to support RapidIO interconnect devices.
  2116. source "drivers/rapidio/Kconfig"
  2117. config X86_SYSFB
  2118. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2119. help
  2120. Firmwares often provide initial graphics framebuffers so the BIOS,
  2121. bootloader or kernel can show basic video-output during boot for
  2122. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2123. Extensions and EFI-framebuffers for this, which are mostly limited
  2124. to x86.
  2125. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2126. framebuffers so the new generic system-framebuffer drivers can be
  2127. used on x86. If the framebuffer is not compatible with the generic
  2128. modes, it is adverticed as fallback platform framebuffer so legacy
  2129. drivers like efifb, vesafb and uvesafb can pick it up.
  2130. If this option is not selected, all system framebuffers are always
  2131. marked as fallback platform framebuffers as usual.
  2132. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2133. not be able to pick up generic system framebuffers if this option
  2134. is selected. You are highly encouraged to enable simplefb as
  2135. replacement if you select this option. simplefb can correctly deal
  2136. with generic system framebuffers. But you should still keep vesafb
  2137. and others enabled as fallback if a system framebuffer is
  2138. incompatible with simplefb.
  2139. If unsure, say Y.
  2140. endmenu
  2141. menu "Executable file formats / Emulations"
  2142. source "fs/Kconfig.binfmt"
  2143. config IA32_EMULATION
  2144. bool "IA32 Emulation"
  2145. depends on X86_64
  2146. select BINFMT_ELF
  2147. select COMPAT_BINFMT_ELF
  2148. select ARCH_WANT_OLD_COMPAT_IPC
  2149. ---help---
  2150. Include code to run legacy 32-bit programs under a
  2151. 64-bit kernel. You should likely turn this on, unless you're
  2152. 100% sure that you don't have any 32-bit programs left.
  2153. config IA32_AOUT
  2154. tristate "IA32 a.out support"
  2155. depends on IA32_EMULATION
  2156. ---help---
  2157. Support old a.out binaries in the 32bit emulation.
  2158. config X86_X32
  2159. bool "x32 ABI for 64-bit mode"
  2160. depends on X86_64
  2161. ---help---
  2162. Include code to run binaries for the x32 native 32-bit ABI
  2163. for 64-bit processors. An x32 process gets access to the
  2164. full 64-bit register file and wide data path while leaving
  2165. pointers at 32 bits for smaller memory footprint.
  2166. You will need a recent binutils (2.22 or later) with
  2167. elf32_x86_64 support enabled to compile a kernel with this
  2168. option set.
  2169. config COMPAT
  2170. def_bool y
  2171. depends on IA32_EMULATION || X86_X32
  2172. if COMPAT
  2173. config COMPAT_FOR_U64_ALIGNMENT
  2174. def_bool y
  2175. config SYSVIPC_COMPAT
  2176. def_bool y
  2177. depends on SYSVIPC
  2178. config KEYS_COMPAT
  2179. def_bool y
  2180. depends on KEYS
  2181. endif
  2182. endmenu
  2183. config HAVE_ATOMIC_IOMAP
  2184. def_bool y
  2185. depends on X86_32
  2186. config X86_DEV_DMA_OPS
  2187. bool
  2188. depends on X86_64 || STA2X11
  2189. config X86_DMA_REMAP
  2190. bool
  2191. depends on STA2X11
  2192. config PMC_ATOM
  2193. def_bool y
  2194. depends on PCI
  2195. source "net/Kconfig"
  2196. source "drivers/Kconfig"
  2197. source "drivers/firmware/Kconfig"
  2198. source "fs/Kconfig"
  2199. source "arch/x86/Kconfig.debug"
  2200. source "security/Kconfig"
  2201. source "crypto/Kconfig"
  2202. source "arch/x86/kvm/Kconfig"
  2203. source "lib/Kconfig"