Kconfig 87 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. bool "CPU microcode loading support"
  960. default y
  961. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  962. depends on BLK_DEV_INITRD
  963. select FW_LOADER
  964. ---help---
  965. If you say Y here, you will be able to update the microcode on
  966. certain Intel and AMD processors. The Intel support is for the
  967. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
  968. Xeon etc. The AMD support is for families 0x10 and later. You will
  969. obviously need the actual microcode binary data itself which is not
  970. shipped with the Linux kernel.
  971. This option selects the general module only, you need to select
  972. at least one vendor specific module as well.
  973. To compile this driver as a module, choose M here: the module
  974. will be called microcode.
  975. config MICROCODE_INTEL
  976. bool "Intel microcode loading support"
  977. depends on MICROCODE
  978. default MICROCODE
  979. select FW_LOADER
  980. ---help---
  981. This options enables microcode patch loading support for Intel
  982. processors.
  983. For the current Intel microcode data package go to
  984. <https://downloadcenter.intel.com> and search for
  985. 'Linux Processor Microcode Data File'.
  986. config MICROCODE_AMD
  987. bool "AMD microcode loading support"
  988. depends on MICROCODE
  989. select FW_LOADER
  990. ---help---
  991. If you select this option, microcode patch loading support for AMD
  992. processors will be enabled.
  993. config MICROCODE_OLD_INTERFACE
  994. def_bool y
  995. depends on MICROCODE
  996. config X86_MSR
  997. tristate "/dev/cpu/*/msr - Model-specific register support"
  998. ---help---
  999. This device gives privileged processes access to the x86
  1000. Model-Specific Registers (MSRs). It is a character device with
  1001. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1002. MSR accesses are directed to a specific CPU on multi-processor
  1003. systems.
  1004. config X86_CPUID
  1005. tristate "/dev/cpu/*/cpuid - CPU information support"
  1006. ---help---
  1007. This device gives processes access to the x86 CPUID instruction to
  1008. be executed on a specific processor. It is a character device
  1009. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1010. /dev/cpu/31/cpuid.
  1011. choice
  1012. prompt "High Memory Support"
  1013. default HIGHMEM4G
  1014. depends on X86_32
  1015. config NOHIGHMEM
  1016. bool "off"
  1017. ---help---
  1018. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1019. However, the address space of 32-bit x86 processors is only 4
  1020. Gigabytes large. That means that, if you have a large amount of
  1021. physical memory, not all of it can be "permanently mapped" by the
  1022. kernel. The physical memory that's not permanently mapped is called
  1023. "high memory".
  1024. If you are compiling a kernel which will never run on a machine with
  1025. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1026. choice and suitable for most users). This will result in a "3GB/1GB"
  1027. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1028. space and the remaining part of the 4GB virtual memory space is used
  1029. by the kernel to permanently map as much physical memory as
  1030. possible.
  1031. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1032. answer "4GB" here.
  1033. If more than 4 Gigabytes is used then answer "64GB" here. This
  1034. selection turns Intel PAE (Physical Address Extension) mode on.
  1035. PAE implements 3-level paging on IA32 processors. PAE is fully
  1036. supported by Linux, PAE mode is implemented on all recent Intel
  1037. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1038. then the kernel will not boot on CPUs that don't support PAE!
  1039. The actual amount of total physical memory will either be
  1040. auto detected or can be forced by using a kernel command line option
  1041. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1042. your boot loader (lilo or loadlin) about how to pass options to the
  1043. kernel at boot time.)
  1044. If unsure, say "off".
  1045. config HIGHMEM4G
  1046. bool "4GB"
  1047. ---help---
  1048. Select this if you have a 32-bit processor and between 1 and 4
  1049. gigabytes of physical RAM.
  1050. config HIGHMEM64G
  1051. bool "64GB"
  1052. depends on !M486
  1053. select X86_PAE
  1054. ---help---
  1055. Select this if you have a 32-bit processor and more than 4
  1056. gigabytes of physical RAM.
  1057. endchoice
  1058. choice
  1059. prompt "Memory split" if EXPERT
  1060. default VMSPLIT_3G
  1061. depends on X86_32
  1062. ---help---
  1063. Select the desired split between kernel and user memory.
  1064. If the address range available to the kernel is less than the
  1065. physical memory installed, the remaining memory will be available
  1066. as "high memory". Accessing high memory is a little more costly
  1067. than low memory, as it needs to be mapped into the kernel first.
  1068. Note that increasing the kernel address space limits the range
  1069. available to user programs, making the address space there
  1070. tighter. Selecting anything other than the default 3G/1G split
  1071. will also likely make your kernel incompatible with binary-only
  1072. kernel modules.
  1073. If you are not absolutely sure what you are doing, leave this
  1074. option alone!
  1075. config VMSPLIT_3G
  1076. bool "3G/1G user/kernel split"
  1077. config VMSPLIT_3G_OPT
  1078. depends on !X86_PAE
  1079. bool "3G/1G user/kernel split (for full 1G low memory)"
  1080. config VMSPLIT_2G
  1081. bool "2G/2G user/kernel split"
  1082. config VMSPLIT_2G_OPT
  1083. depends on !X86_PAE
  1084. bool "2G/2G user/kernel split (for full 2G low memory)"
  1085. config VMSPLIT_1G
  1086. bool "1G/3G user/kernel split"
  1087. endchoice
  1088. config PAGE_OFFSET
  1089. hex
  1090. default 0xB0000000 if VMSPLIT_3G_OPT
  1091. default 0x80000000 if VMSPLIT_2G
  1092. default 0x78000000 if VMSPLIT_2G_OPT
  1093. default 0x40000000 if VMSPLIT_1G
  1094. default 0xC0000000
  1095. depends on X86_32
  1096. config HIGHMEM
  1097. def_bool y
  1098. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1099. config X86_PAE
  1100. bool "PAE (Physical Address Extension) Support"
  1101. depends on X86_32 && !HIGHMEM4G
  1102. select SWIOTLB
  1103. ---help---
  1104. PAE is required for NX support, and furthermore enables
  1105. larger swapspace support for non-overcommit purposes. It
  1106. has the cost of more pagetable lookup overhead, and also
  1107. consumes more pagetable space per process.
  1108. config ARCH_PHYS_ADDR_T_64BIT
  1109. def_bool y
  1110. depends on X86_64 || X86_PAE
  1111. config ARCH_DMA_ADDR_T_64BIT
  1112. def_bool y
  1113. depends on X86_64 || HIGHMEM64G
  1114. config X86_DIRECT_GBPAGES
  1115. def_bool y
  1116. depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
  1117. ---help---
  1118. Certain kernel features effectively disable kernel
  1119. linear 1 GB mappings (even if the CPU otherwise
  1120. supports them), so don't confuse the user by printing
  1121. that we have them enabled.
  1122. # Common NUMA Features
  1123. config NUMA
  1124. bool "Numa Memory Allocation and Scheduler Support"
  1125. depends on SMP
  1126. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1127. default y if X86_BIGSMP
  1128. ---help---
  1129. Enable NUMA (Non Uniform Memory Access) support.
  1130. The kernel will try to allocate memory used by a CPU on the
  1131. local memory controller of the CPU and add some more
  1132. NUMA awareness to the kernel.
  1133. For 64-bit this is recommended if the system is Intel Core i7
  1134. (or later), AMD Opteron, or EM64T NUMA.
  1135. For 32-bit this is only needed if you boot a 32-bit
  1136. kernel on a 64-bit NUMA platform.
  1137. Otherwise, you should say N.
  1138. config AMD_NUMA
  1139. def_bool y
  1140. prompt "Old style AMD Opteron NUMA detection"
  1141. depends on X86_64 && NUMA && PCI
  1142. ---help---
  1143. Enable AMD NUMA node topology detection. You should say Y here if
  1144. you have a multi processor AMD system. This uses an old method to
  1145. read the NUMA configuration directly from the builtin Northbridge
  1146. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1147. which also takes priority if both are compiled in.
  1148. config X86_64_ACPI_NUMA
  1149. def_bool y
  1150. prompt "ACPI NUMA detection"
  1151. depends on X86_64 && NUMA && ACPI && PCI
  1152. select ACPI_NUMA
  1153. ---help---
  1154. Enable ACPI SRAT based node topology detection.
  1155. # Some NUMA nodes have memory ranges that span
  1156. # other nodes. Even though a pfn is valid and
  1157. # between a node's start and end pfns, it may not
  1158. # reside on that node. See memmap_init_zone()
  1159. # for details.
  1160. config NODES_SPAN_OTHER_NODES
  1161. def_bool y
  1162. depends on X86_64_ACPI_NUMA
  1163. config NUMA_EMU
  1164. bool "NUMA emulation"
  1165. depends on NUMA
  1166. ---help---
  1167. Enable NUMA emulation. A flat machine will be split
  1168. into virtual nodes when booted with "numa=fake=N", where N is the
  1169. number of nodes. This is only useful for debugging.
  1170. config NODES_SHIFT
  1171. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1172. range 1 10
  1173. default "10" if MAXSMP
  1174. default "6" if X86_64
  1175. default "3"
  1176. depends on NEED_MULTIPLE_NODES
  1177. ---help---
  1178. Specify the maximum number of NUMA Nodes available on the target
  1179. system. Increases memory reserved to accommodate various tables.
  1180. config ARCH_HAVE_MEMORY_PRESENT
  1181. def_bool y
  1182. depends on X86_32 && DISCONTIGMEM
  1183. config NEED_NODE_MEMMAP_SIZE
  1184. def_bool y
  1185. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1186. config ARCH_FLATMEM_ENABLE
  1187. def_bool y
  1188. depends on X86_32 && !NUMA
  1189. config ARCH_DISCONTIGMEM_ENABLE
  1190. def_bool y
  1191. depends on NUMA && X86_32
  1192. config ARCH_DISCONTIGMEM_DEFAULT
  1193. def_bool y
  1194. depends on NUMA && X86_32
  1195. config ARCH_SPARSEMEM_ENABLE
  1196. def_bool y
  1197. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1198. select SPARSEMEM_STATIC if X86_32
  1199. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1200. config ARCH_SPARSEMEM_DEFAULT
  1201. def_bool y
  1202. depends on X86_64
  1203. config ARCH_SELECT_MEMORY_MODEL
  1204. def_bool y
  1205. depends on ARCH_SPARSEMEM_ENABLE
  1206. config ARCH_MEMORY_PROBE
  1207. bool "Enable sysfs memory/probe interface"
  1208. depends on X86_64 && MEMORY_HOTPLUG
  1209. help
  1210. This option enables a sysfs memory/probe interface for testing.
  1211. See Documentation/memory-hotplug.txt for more information.
  1212. If you are unsure how to answer this question, answer N.
  1213. config ARCH_PROC_KCORE_TEXT
  1214. def_bool y
  1215. depends on X86_64 && PROC_KCORE
  1216. config ILLEGAL_POINTER_VALUE
  1217. hex
  1218. default 0 if X86_32
  1219. default 0xdead000000000000 if X86_64
  1220. source "mm/Kconfig"
  1221. config X86_PMEM_LEGACY_DEVICE
  1222. bool
  1223. config X86_PMEM_LEGACY
  1224. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1225. depends on PHYS_ADDR_T_64BIT
  1226. depends on BLK_DEV
  1227. select X86_PMEM_LEGACY_DEVICE
  1228. select LIBNVDIMM
  1229. help
  1230. Treat memory marked using the non-standard e820 type of 12 as used
  1231. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1232. The kernel will offer these regions to the 'pmem' driver so
  1233. they can be used for persistent storage.
  1234. Say Y if unsure.
  1235. config HIGHPTE
  1236. bool "Allocate 3rd-level pagetables from highmem"
  1237. depends on HIGHMEM
  1238. ---help---
  1239. The VM uses one page table entry for each page of physical memory.
  1240. For systems with a lot of RAM, this can be wasteful of precious
  1241. low memory. Setting this option will put user-space page table
  1242. entries in high memory.
  1243. config X86_CHECK_BIOS_CORRUPTION
  1244. bool "Check for low memory corruption"
  1245. ---help---
  1246. Periodically check for memory corruption in low memory, which
  1247. is suspected to be caused by BIOS. Even when enabled in the
  1248. configuration, it is disabled at runtime. Enable it by
  1249. setting "memory_corruption_check=1" on the kernel command
  1250. line. By default it scans the low 64k of memory every 60
  1251. seconds; see the memory_corruption_check_size and
  1252. memory_corruption_check_period parameters in
  1253. Documentation/kernel-parameters.txt to adjust this.
  1254. When enabled with the default parameters, this option has
  1255. almost no overhead, as it reserves a relatively small amount
  1256. of memory and scans it infrequently. It both detects corruption
  1257. and prevents it from affecting the running system.
  1258. It is, however, intended as a diagnostic tool; if repeatable
  1259. BIOS-originated corruption always affects the same memory,
  1260. you can use memmap= to prevent the kernel from using that
  1261. memory.
  1262. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1263. bool "Set the default setting of memory_corruption_check"
  1264. depends on X86_CHECK_BIOS_CORRUPTION
  1265. default y
  1266. ---help---
  1267. Set whether the default state of memory_corruption_check is
  1268. on or off.
  1269. config X86_RESERVE_LOW
  1270. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1271. default 64
  1272. range 4 640
  1273. ---help---
  1274. Specify the amount of low memory to reserve for the BIOS.
  1275. The first page contains BIOS data structures that the kernel
  1276. must not use, so that page must always be reserved.
  1277. By default we reserve the first 64K of physical RAM, as a
  1278. number of BIOSes are known to corrupt that memory range
  1279. during events such as suspend/resume or monitor cable
  1280. insertion, so it must not be used by the kernel.
  1281. You can set this to 4 if you are absolutely sure that you
  1282. trust the BIOS to get all its memory reservations and usages
  1283. right. If you know your BIOS have problems beyond the
  1284. default 64K area, you can set this to 640 to avoid using the
  1285. entire low memory range.
  1286. If you have doubts about the BIOS (e.g. suspend/resume does
  1287. not work or there's kernel crashes after certain hardware
  1288. hotplug events) then you might want to enable
  1289. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1290. typical corruption patterns.
  1291. Leave this to the default value of 64 if you are unsure.
  1292. config MATH_EMULATION
  1293. bool
  1294. depends on MODIFY_LDT_SYSCALL
  1295. prompt "Math emulation" if X86_32
  1296. ---help---
  1297. Linux can emulate a math coprocessor (used for floating point
  1298. operations) if you don't have one. 486DX and Pentium processors have
  1299. a math coprocessor built in, 486SX and 386 do not, unless you added
  1300. a 487DX or 387, respectively. (The messages during boot time can
  1301. give you some hints here ["man dmesg"].) Everyone needs either a
  1302. coprocessor or this emulation.
  1303. If you don't have a math coprocessor, you need to say Y here; if you
  1304. say Y here even though you have a coprocessor, the coprocessor will
  1305. be used nevertheless. (This behavior can be changed with the kernel
  1306. command line option "no387", which comes handy if your coprocessor
  1307. is broken. Try "man bootparam" or see the documentation of your boot
  1308. loader (lilo or loadlin) about how to pass options to the kernel at
  1309. boot time.) This means that it is a good idea to say Y here if you
  1310. intend to use this kernel on different machines.
  1311. More information about the internals of the Linux math coprocessor
  1312. emulation can be found in <file:arch/x86/math-emu/README>.
  1313. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1314. kernel, it won't hurt.
  1315. config MTRR
  1316. def_bool y
  1317. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1318. ---help---
  1319. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1320. the Memory Type Range Registers (MTRRs) may be used to control
  1321. processor access to memory ranges. This is most useful if you have
  1322. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1323. allows bus write transfers to be combined into a larger transfer
  1324. before bursting over the PCI/AGP bus. This can increase performance
  1325. of image write operations 2.5 times or more. Saying Y here creates a
  1326. /proc/mtrr file which may be used to manipulate your processor's
  1327. MTRRs. Typically the X server should use this.
  1328. This code has a reasonably generic interface so that similar
  1329. control registers on other processors can be easily supported
  1330. as well:
  1331. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1332. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1333. these, the ARRs are used to emulate the MTRRs.
  1334. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1335. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1336. write-combining. All of these processors are supported by this code
  1337. and it makes sense to say Y here if you have one of them.
  1338. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1339. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1340. can lead to all sorts of problems, so it's good to say Y here.
  1341. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1342. just add about 9 KB to your kernel.
  1343. See <file:Documentation/x86/mtrr.txt> for more information.
  1344. config MTRR_SANITIZER
  1345. def_bool y
  1346. prompt "MTRR cleanup support"
  1347. depends on MTRR
  1348. ---help---
  1349. Convert MTRR layout from continuous to discrete, so X drivers can
  1350. add writeback entries.
  1351. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1352. The largest mtrr entry size for a continuous block can be set with
  1353. mtrr_chunk_size.
  1354. If unsure, say Y.
  1355. config MTRR_SANITIZER_ENABLE_DEFAULT
  1356. int "MTRR cleanup enable value (0-1)"
  1357. range 0 1
  1358. default "0"
  1359. depends on MTRR_SANITIZER
  1360. ---help---
  1361. Enable mtrr cleanup default value
  1362. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1363. int "MTRR cleanup spare reg num (0-7)"
  1364. range 0 7
  1365. default "1"
  1366. depends on MTRR_SANITIZER
  1367. ---help---
  1368. mtrr cleanup spare entries default, it can be changed via
  1369. mtrr_spare_reg_nr=N on the kernel command line.
  1370. config X86_PAT
  1371. def_bool y
  1372. prompt "x86 PAT support" if EXPERT
  1373. depends on MTRR
  1374. ---help---
  1375. Use PAT attributes to setup page level cache control.
  1376. PATs are the modern equivalents of MTRRs and are much more
  1377. flexible than MTRRs.
  1378. Say N here if you see bootup problems (boot crash, boot hang,
  1379. spontaneous reboots) or a non-working video driver.
  1380. If unsure, say Y.
  1381. config ARCH_USES_PG_UNCACHED
  1382. def_bool y
  1383. depends on X86_PAT
  1384. config ARCH_RANDOM
  1385. def_bool y
  1386. prompt "x86 architectural random number generator" if EXPERT
  1387. ---help---
  1388. Enable the x86 architectural RDRAND instruction
  1389. (Intel Bull Mountain technology) to generate random numbers.
  1390. If supported, this is a high bandwidth, cryptographically
  1391. secure hardware random number generator.
  1392. config X86_SMAP
  1393. def_bool y
  1394. prompt "Supervisor Mode Access Prevention" if EXPERT
  1395. ---help---
  1396. Supervisor Mode Access Prevention (SMAP) is a security
  1397. feature in newer Intel processors. There is a small
  1398. performance cost if this enabled and turned on; there is
  1399. also a small increase in the kernel size if this is enabled.
  1400. If unsure, say Y.
  1401. config X86_INTEL_MPX
  1402. prompt "Intel MPX (Memory Protection Extensions)"
  1403. def_bool n
  1404. depends on CPU_SUP_INTEL
  1405. ---help---
  1406. MPX provides hardware features that can be used in
  1407. conjunction with compiler-instrumented code to check
  1408. memory references. It is designed to detect buffer
  1409. overflow or underflow bugs.
  1410. This option enables running applications which are
  1411. instrumented or otherwise use MPX. It does not use MPX
  1412. itself inside the kernel or to protect the kernel
  1413. against bad memory references.
  1414. Enabling this option will make the kernel larger:
  1415. ~8k of kernel text and 36 bytes of data on a 64-bit
  1416. defconfig. It adds a long to the 'mm_struct' which
  1417. will increase the kernel memory overhead of each
  1418. process and adds some branches to paths used during
  1419. exec() and munmap().
  1420. For details, see Documentation/x86/intel_mpx.txt
  1421. If unsure, say N.
  1422. config EFI
  1423. bool "EFI runtime service support"
  1424. depends on ACPI
  1425. select UCS2_STRING
  1426. select EFI_RUNTIME_WRAPPERS
  1427. ---help---
  1428. This enables the kernel to use EFI runtime services that are
  1429. available (such as the EFI variable services).
  1430. This option is only useful on systems that have EFI firmware.
  1431. In addition, you should use the latest ELILO loader available
  1432. at <http://elilo.sourceforge.net> in order to take advantage
  1433. of EFI runtime services. However, even with this option, the
  1434. resultant kernel should continue to boot on existing non-EFI
  1435. platforms.
  1436. config EFI_STUB
  1437. bool "EFI stub support"
  1438. depends on EFI && !X86_USE_3DNOW
  1439. select RELOCATABLE
  1440. ---help---
  1441. This kernel feature allows a bzImage to be loaded directly
  1442. by EFI firmware without the use of a bootloader.
  1443. See Documentation/efi-stub.txt for more information.
  1444. config EFI_MIXED
  1445. bool "EFI mixed-mode support"
  1446. depends on EFI_STUB && X86_64
  1447. ---help---
  1448. Enabling this feature allows a 64-bit kernel to be booted
  1449. on a 32-bit firmware, provided that your CPU supports 64-bit
  1450. mode.
  1451. Note that it is not possible to boot a mixed-mode enabled
  1452. kernel via the EFI boot stub - a bootloader that supports
  1453. the EFI handover protocol must be used.
  1454. If unsure, say N.
  1455. config SECCOMP
  1456. def_bool y
  1457. prompt "Enable seccomp to safely compute untrusted bytecode"
  1458. ---help---
  1459. This kernel feature is useful for number crunching applications
  1460. that may need to compute untrusted bytecode during their
  1461. execution. By using pipes or other transports made available to
  1462. the process as file descriptors supporting the read/write
  1463. syscalls, it's possible to isolate those applications in
  1464. their own address space using seccomp. Once seccomp is
  1465. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1466. and the task is only allowed to execute a few safe syscalls
  1467. defined by each seccomp mode.
  1468. If unsure, say Y. Only embedded should say N here.
  1469. source kernel/Kconfig.hz
  1470. config KEXEC
  1471. bool "kexec system call"
  1472. select KEXEC_CORE
  1473. ---help---
  1474. kexec is a system call that implements the ability to shutdown your
  1475. current kernel, and to start another kernel. It is like a reboot
  1476. but it is independent of the system firmware. And like a reboot
  1477. you can start any kernel with it, not just Linux.
  1478. The name comes from the similarity to the exec system call.
  1479. It is an ongoing process to be certain the hardware in a machine
  1480. is properly shutdown, so do not be surprised if this code does not
  1481. initially work for you. As of this writing the exact hardware
  1482. interface is strongly in flux, so no good recommendation can be
  1483. made.
  1484. config KEXEC_FILE
  1485. bool "kexec file based system call"
  1486. select KEXEC_CORE
  1487. select BUILD_BIN2C
  1488. depends on X86_64
  1489. depends on CRYPTO=y
  1490. depends on CRYPTO_SHA256=y
  1491. ---help---
  1492. This is new version of kexec system call. This system call is
  1493. file based and takes file descriptors as system call argument
  1494. for kernel and initramfs as opposed to list of segments as
  1495. accepted by previous system call.
  1496. config KEXEC_VERIFY_SIG
  1497. bool "Verify kernel signature during kexec_file_load() syscall"
  1498. depends on KEXEC_FILE
  1499. ---help---
  1500. This option makes kernel signature verification mandatory for
  1501. the kexec_file_load() syscall.
  1502. In addition to that option, you need to enable signature
  1503. verification for the corresponding kernel image type being
  1504. loaded in order for this to work.
  1505. config KEXEC_BZIMAGE_VERIFY_SIG
  1506. bool "Enable bzImage signature verification support"
  1507. depends on KEXEC_VERIFY_SIG
  1508. depends on SIGNED_PE_FILE_VERIFICATION
  1509. select SYSTEM_TRUSTED_KEYRING
  1510. ---help---
  1511. Enable bzImage signature verification support.
  1512. config CRASH_DUMP
  1513. bool "kernel crash dumps"
  1514. depends on X86_64 || (X86_32 && HIGHMEM)
  1515. ---help---
  1516. Generate crash dump after being started by kexec.
  1517. This should be normally only set in special crash dump kernels
  1518. which are loaded in the main kernel with kexec-tools into
  1519. a specially reserved region and then later executed after
  1520. a crash by kdump/kexec. The crash dump kernel must be compiled
  1521. to a memory address not used by the main kernel or BIOS using
  1522. PHYSICAL_START, or it must be built as a relocatable image
  1523. (CONFIG_RELOCATABLE=y).
  1524. For more details see Documentation/kdump/kdump.txt
  1525. config KEXEC_JUMP
  1526. bool "kexec jump"
  1527. depends on KEXEC && HIBERNATION
  1528. ---help---
  1529. Jump between original kernel and kexeced kernel and invoke
  1530. code in physical address mode via KEXEC
  1531. config PHYSICAL_START
  1532. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1533. default "0x1000000"
  1534. ---help---
  1535. This gives the physical address where the kernel is loaded.
  1536. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1537. bzImage will decompress itself to above physical address and
  1538. run from there. Otherwise, bzImage will run from the address where
  1539. it has been loaded by the boot loader and will ignore above physical
  1540. address.
  1541. In normal kdump cases one does not have to set/change this option
  1542. as now bzImage can be compiled as a completely relocatable image
  1543. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1544. address. This option is mainly useful for the folks who don't want
  1545. to use a bzImage for capturing the crash dump and want to use a
  1546. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1547. to be specifically compiled to run from a specific memory area
  1548. (normally a reserved region) and this option comes handy.
  1549. So if you are using bzImage for capturing the crash dump,
  1550. leave the value here unchanged to 0x1000000 and set
  1551. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1552. for capturing the crash dump change this value to start of
  1553. the reserved region. In other words, it can be set based on
  1554. the "X" value as specified in the "crashkernel=YM@XM"
  1555. command line boot parameter passed to the panic-ed
  1556. kernel. Please take a look at Documentation/kdump/kdump.txt
  1557. for more details about crash dumps.
  1558. Usage of bzImage for capturing the crash dump is recommended as
  1559. one does not have to build two kernels. Same kernel can be used
  1560. as production kernel and capture kernel. Above option should have
  1561. gone away after relocatable bzImage support is introduced. But it
  1562. is present because there are users out there who continue to use
  1563. vmlinux for dump capture. This option should go away down the
  1564. line.
  1565. Don't change this unless you know what you are doing.
  1566. config RELOCATABLE
  1567. bool "Build a relocatable kernel"
  1568. default y
  1569. ---help---
  1570. This builds a kernel image that retains relocation information
  1571. so it can be loaded someplace besides the default 1MB.
  1572. The relocations tend to make the kernel binary about 10% larger,
  1573. but are discarded at runtime.
  1574. One use is for the kexec on panic case where the recovery kernel
  1575. must live at a different physical address than the primary
  1576. kernel.
  1577. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1578. it has been loaded at and the compile time physical address
  1579. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1580. config RANDOMIZE_BASE
  1581. bool "Randomize the address of the kernel image"
  1582. depends on RELOCATABLE
  1583. default n
  1584. ---help---
  1585. Randomizes the physical and virtual address at which the
  1586. kernel image is decompressed, as a security feature that
  1587. deters exploit attempts relying on knowledge of the location
  1588. of kernel internals.
  1589. Entropy is generated using the RDRAND instruction if it is
  1590. supported. If RDTSC is supported, it is used as well. If
  1591. neither RDRAND nor RDTSC are supported, then randomness is
  1592. read from the i8254 timer.
  1593. The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
  1594. and aligned according to PHYSICAL_ALIGN. Since the kernel is
  1595. built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
  1596. minimum of 2MiB, only 10 bits of entropy is theoretically
  1597. possible. At best, due to page table layouts, 64-bit can use
  1598. 9 bits of entropy and 32-bit uses 8 bits.
  1599. If unsure, say N.
  1600. config RANDOMIZE_BASE_MAX_OFFSET
  1601. hex "Maximum kASLR offset allowed" if EXPERT
  1602. depends on RANDOMIZE_BASE
  1603. range 0x0 0x20000000 if X86_32
  1604. default "0x20000000" if X86_32
  1605. range 0x0 0x40000000 if X86_64
  1606. default "0x40000000" if X86_64
  1607. ---help---
  1608. The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
  1609. memory is used to determine the maximal offset in bytes that will
  1610. be applied to the kernel when kernel Address Space Layout
  1611. Randomization (kASLR) is active. This must be a multiple of
  1612. PHYSICAL_ALIGN.
  1613. On 32-bit this is limited to 512MiB by page table layouts. The
  1614. default is 512MiB.
  1615. On 64-bit this is limited by how the kernel fixmap page table is
  1616. positioned, so this cannot be larger than 1GiB currently. Without
  1617. RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
  1618. and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
  1619. modules area will shrink to compensate, up to the current maximum
  1620. 1GiB to 1GiB split. The default is 1GiB.
  1621. If unsure, leave at the default value.
  1622. # Relocation on x86 needs some additional build support
  1623. config X86_NEED_RELOCS
  1624. def_bool y
  1625. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1626. config PHYSICAL_ALIGN
  1627. hex "Alignment value to which kernel should be aligned"
  1628. default "0x200000"
  1629. range 0x2000 0x1000000 if X86_32
  1630. range 0x200000 0x1000000 if X86_64
  1631. ---help---
  1632. This value puts the alignment restrictions on physical address
  1633. where kernel is loaded and run from. Kernel is compiled for an
  1634. address which meets above alignment restriction.
  1635. If bootloader loads the kernel at a non-aligned address and
  1636. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1637. address aligned to above value and run from there.
  1638. If bootloader loads the kernel at a non-aligned address and
  1639. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1640. load address and decompress itself to the address it has been
  1641. compiled for and run from there. The address for which kernel is
  1642. compiled already meets above alignment restrictions. Hence the
  1643. end result is that kernel runs from a physical address meeting
  1644. above alignment restrictions.
  1645. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1646. this value must be a multiple of 0x200000.
  1647. Don't change this unless you know what you are doing.
  1648. config HOTPLUG_CPU
  1649. bool "Support for hot-pluggable CPUs"
  1650. depends on SMP
  1651. ---help---
  1652. Say Y here to allow turning CPUs off and on. CPUs can be
  1653. controlled through /sys/devices/system/cpu.
  1654. ( Note: power management support will enable this option
  1655. automatically on SMP systems. )
  1656. Say N if you want to disable CPU hotplug.
  1657. config BOOTPARAM_HOTPLUG_CPU0
  1658. bool "Set default setting of cpu0_hotpluggable"
  1659. default n
  1660. depends on HOTPLUG_CPU
  1661. ---help---
  1662. Set whether default state of cpu0_hotpluggable is on or off.
  1663. Say Y here to enable CPU0 hotplug by default. If this switch
  1664. is turned on, there is no need to give cpu0_hotplug kernel
  1665. parameter and the CPU0 hotplug feature is enabled by default.
  1666. Please note: there are two known CPU0 dependencies if you want
  1667. to enable the CPU0 hotplug feature either by this switch or by
  1668. cpu0_hotplug kernel parameter.
  1669. First, resume from hibernate or suspend always starts from CPU0.
  1670. So hibernate and suspend are prevented if CPU0 is offline.
  1671. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1672. offline if any interrupt can not migrate out of CPU0. There may
  1673. be other CPU0 dependencies.
  1674. Please make sure the dependencies are under your control before
  1675. you enable this feature.
  1676. Say N if you don't want to enable CPU0 hotplug feature by default.
  1677. You still can enable the CPU0 hotplug feature at boot by kernel
  1678. parameter cpu0_hotplug.
  1679. config DEBUG_HOTPLUG_CPU0
  1680. def_bool n
  1681. prompt "Debug CPU0 hotplug"
  1682. depends on HOTPLUG_CPU
  1683. ---help---
  1684. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1685. soon as possible and boots up userspace with CPU0 offlined. User
  1686. can online CPU0 back after boot time.
  1687. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1688. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1689. compilation or giving cpu0_hotplug kernel parameter at boot.
  1690. If unsure, say N.
  1691. config COMPAT_VDSO
  1692. def_bool n
  1693. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1694. depends on X86_32 || IA32_EMULATION
  1695. ---help---
  1696. Certain buggy versions of glibc will crash if they are
  1697. presented with a 32-bit vDSO that is not mapped at the address
  1698. indicated in its segment table.
  1699. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1700. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1701. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1702. the only released version with the bug, but OpenSUSE 9
  1703. contains a buggy "glibc 2.3.2".
  1704. The symptom of the bug is that everything crashes on startup, saying:
  1705. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1706. Saying Y here changes the default value of the vdso32 boot
  1707. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1708. This works around the glibc bug but hurts performance.
  1709. If unsure, say N: if you are compiling your own kernel, you
  1710. are unlikely to be using a buggy version of glibc.
  1711. choice
  1712. prompt "vsyscall table for legacy applications"
  1713. depends on X86_64
  1714. default LEGACY_VSYSCALL_EMULATE
  1715. help
  1716. Legacy user code that does not know how to find the vDSO expects
  1717. to be able to issue three syscalls by calling fixed addresses in
  1718. kernel space. Since this location is not randomized with ASLR,
  1719. it can be used to assist security vulnerability exploitation.
  1720. This setting can be changed at boot time via the kernel command
  1721. line parameter vsyscall=[native|emulate|none].
  1722. On a system with recent enough glibc (2.14 or newer) and no
  1723. static binaries, you can say None without a performance penalty
  1724. to improve security.
  1725. If unsure, select "Emulate".
  1726. config LEGACY_VSYSCALL_NATIVE
  1727. bool "Native"
  1728. help
  1729. Actual executable code is located in the fixed vsyscall
  1730. address mapping, implementing time() efficiently. Since
  1731. this makes the mapping executable, it can be used during
  1732. security vulnerability exploitation (traditionally as
  1733. ROP gadgets). This configuration is not recommended.
  1734. config LEGACY_VSYSCALL_EMULATE
  1735. bool "Emulate"
  1736. help
  1737. The kernel traps and emulates calls into the fixed
  1738. vsyscall address mapping. This makes the mapping
  1739. non-executable, but it still contains known contents,
  1740. which could be used in certain rare security vulnerability
  1741. exploits. This configuration is recommended when userspace
  1742. still uses the vsyscall area.
  1743. config LEGACY_VSYSCALL_NONE
  1744. bool "None"
  1745. help
  1746. There will be no vsyscall mapping at all. This will
  1747. eliminate any risk of ASLR bypass due to the vsyscall
  1748. fixed address mapping. Attempts to use the vsyscalls
  1749. will be reported to dmesg, so that either old or
  1750. malicious userspace programs can be identified.
  1751. endchoice
  1752. config CMDLINE_BOOL
  1753. bool "Built-in kernel command line"
  1754. ---help---
  1755. Allow for specifying boot arguments to the kernel at
  1756. build time. On some systems (e.g. embedded ones), it is
  1757. necessary or convenient to provide some or all of the
  1758. kernel boot arguments with the kernel itself (that is,
  1759. to not rely on the boot loader to provide them.)
  1760. To compile command line arguments into the kernel,
  1761. set this option to 'Y', then fill in the
  1762. boot arguments in CONFIG_CMDLINE.
  1763. Systems with fully functional boot loaders (i.e. non-embedded)
  1764. should leave this option set to 'N'.
  1765. config CMDLINE
  1766. string "Built-in kernel command string"
  1767. depends on CMDLINE_BOOL
  1768. default ""
  1769. ---help---
  1770. Enter arguments here that should be compiled into the kernel
  1771. image and used at boot time. If the boot loader provides a
  1772. command line at boot time, it is appended to this string to
  1773. form the full kernel command line, when the system boots.
  1774. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1775. change this behavior.
  1776. In most cases, the command line (whether built-in or provided
  1777. by the boot loader) should specify the device for the root
  1778. file system.
  1779. config CMDLINE_OVERRIDE
  1780. bool "Built-in command line overrides boot loader arguments"
  1781. depends on CMDLINE_BOOL
  1782. ---help---
  1783. Set this option to 'Y' to have the kernel ignore the boot loader
  1784. command line, and use ONLY the built-in command line.
  1785. This is used to work around broken boot loaders. This should
  1786. be set to 'N' under normal conditions.
  1787. config MODIFY_LDT_SYSCALL
  1788. bool "Enable the LDT (local descriptor table)" if EXPERT
  1789. default y
  1790. ---help---
  1791. Linux can allow user programs to install a per-process x86
  1792. Local Descriptor Table (LDT) using the modify_ldt(2) system
  1793. call. This is required to run 16-bit or segmented code such as
  1794. DOSEMU or some Wine programs. It is also used by some very old
  1795. threading libraries.
  1796. Enabling this feature adds a small amount of overhead to
  1797. context switches and increases the low-level kernel attack
  1798. surface. Disabling it removes the modify_ldt(2) system call.
  1799. Saying 'N' here may make sense for embedded or server kernels.
  1800. source "kernel/livepatch/Kconfig"
  1801. endmenu
  1802. config ARCH_ENABLE_MEMORY_HOTPLUG
  1803. def_bool y
  1804. depends on X86_64 || (X86_32 && HIGHMEM)
  1805. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1806. def_bool y
  1807. depends on MEMORY_HOTPLUG
  1808. config USE_PERCPU_NUMA_NODE_ID
  1809. def_bool y
  1810. depends on NUMA
  1811. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  1812. def_bool y
  1813. depends on X86_64 || X86_PAE
  1814. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  1815. def_bool y
  1816. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  1817. menu "Power management and ACPI options"
  1818. config ARCH_HIBERNATION_HEADER
  1819. def_bool y
  1820. depends on X86_64 && HIBERNATION
  1821. source "kernel/power/Kconfig"
  1822. source "drivers/acpi/Kconfig"
  1823. source "drivers/sfi/Kconfig"
  1824. config X86_APM_BOOT
  1825. def_bool y
  1826. depends on APM
  1827. menuconfig APM
  1828. tristate "APM (Advanced Power Management) BIOS support"
  1829. depends on X86_32 && PM_SLEEP
  1830. ---help---
  1831. APM is a BIOS specification for saving power using several different
  1832. techniques. This is mostly useful for battery powered laptops with
  1833. APM compliant BIOSes. If you say Y here, the system time will be
  1834. reset after a RESUME operation, the /proc/apm device will provide
  1835. battery status information, and user-space programs will receive
  1836. notification of APM "events" (e.g. battery status change).
  1837. If you select "Y" here, you can disable actual use of the APM
  1838. BIOS by passing the "apm=off" option to the kernel at boot time.
  1839. Note that the APM support is almost completely disabled for
  1840. machines with more than one CPU.
  1841. In order to use APM, you will need supporting software. For location
  1842. and more information, read <file:Documentation/power/apm-acpi.txt>
  1843. and the Battery Powered Linux mini-HOWTO, available from
  1844. <http://www.tldp.org/docs.html#howto>.
  1845. This driver does not spin down disk drives (see the hdparm(8)
  1846. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1847. VESA-compliant "green" monitors.
  1848. This driver does not support the TI 4000M TravelMate and the ACER
  1849. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1850. desktop machines also don't have compliant BIOSes, and this driver
  1851. may cause those machines to panic during the boot phase.
  1852. Generally, if you don't have a battery in your machine, there isn't
  1853. much point in using this driver and you should say N. If you get
  1854. random kernel OOPSes or reboots that don't seem to be related to
  1855. anything, try disabling/enabling this option (or disabling/enabling
  1856. APM in your BIOS).
  1857. Some other things you should try when experiencing seemingly random,
  1858. "weird" problems:
  1859. 1) make sure that you have enough swap space and that it is
  1860. enabled.
  1861. 2) pass the "no-hlt" option to the kernel
  1862. 3) switch on floating point emulation in the kernel and pass
  1863. the "no387" option to the kernel
  1864. 4) pass the "floppy=nodma" option to the kernel
  1865. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1866. all but the first 4 MB of RAM)
  1867. 6) make sure that the CPU is not over clocked.
  1868. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1869. 8) disable the cache from your BIOS settings
  1870. 9) install a fan for the video card or exchange video RAM
  1871. 10) install a better fan for the CPU
  1872. 11) exchange RAM chips
  1873. 12) exchange the motherboard.
  1874. To compile this driver as a module, choose M here: the
  1875. module will be called apm.
  1876. if APM
  1877. config APM_IGNORE_USER_SUSPEND
  1878. bool "Ignore USER SUSPEND"
  1879. ---help---
  1880. This option will ignore USER SUSPEND requests. On machines with a
  1881. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1882. series notebooks, it is necessary to say Y because of a BIOS bug.
  1883. config APM_DO_ENABLE
  1884. bool "Enable PM at boot time"
  1885. ---help---
  1886. Enable APM features at boot time. From page 36 of the APM BIOS
  1887. specification: "When disabled, the APM BIOS does not automatically
  1888. power manage devices, enter the Standby State, enter the Suspend
  1889. State, or take power saving steps in response to CPU Idle calls."
  1890. This driver will make CPU Idle calls when Linux is idle (unless this
  1891. feature is turned off -- see "Do CPU IDLE calls", below). This
  1892. should always save battery power, but more complicated APM features
  1893. will be dependent on your BIOS implementation. You may need to turn
  1894. this option off if your computer hangs at boot time when using APM
  1895. support, or if it beeps continuously instead of suspending. Turn
  1896. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1897. T400CDT. This is off by default since most machines do fine without
  1898. this feature.
  1899. config APM_CPU_IDLE
  1900. depends on CPU_IDLE
  1901. bool "Make CPU Idle calls when idle"
  1902. ---help---
  1903. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1904. On some machines, this can activate improved power savings, such as
  1905. a slowed CPU clock rate, when the machine is idle. These idle calls
  1906. are made after the idle loop has run for some length of time (e.g.,
  1907. 333 mS). On some machines, this will cause a hang at boot time or
  1908. whenever the CPU becomes idle. (On machines with more than one CPU,
  1909. this option does nothing.)
  1910. config APM_DISPLAY_BLANK
  1911. bool "Enable console blanking using APM"
  1912. ---help---
  1913. Enable console blanking using the APM. Some laptops can use this to
  1914. turn off the LCD backlight when the screen blanker of the Linux
  1915. virtual console blanks the screen. Note that this is only used by
  1916. the virtual console screen blanker, and won't turn off the backlight
  1917. when using the X Window system. This also doesn't have anything to
  1918. do with your VESA-compliant power-saving monitor. Further, this
  1919. option doesn't work for all laptops -- it might not turn off your
  1920. backlight at all, or it might print a lot of errors to the console,
  1921. especially if you are using gpm.
  1922. config APM_ALLOW_INTS
  1923. bool "Allow interrupts during APM BIOS calls"
  1924. ---help---
  1925. Normally we disable external interrupts while we are making calls to
  1926. the APM BIOS as a measure to lessen the effects of a badly behaving
  1927. BIOS implementation. The BIOS should reenable interrupts if it
  1928. needs to. Unfortunately, some BIOSes do not -- especially those in
  1929. many of the newer IBM Thinkpads. If you experience hangs when you
  1930. suspend, try setting this to Y. Otherwise, say N.
  1931. endif # APM
  1932. source "drivers/cpufreq/Kconfig"
  1933. source "drivers/cpuidle/Kconfig"
  1934. source "drivers/idle/Kconfig"
  1935. endmenu
  1936. menu "Bus options (PCI etc.)"
  1937. config PCI
  1938. bool "PCI support"
  1939. default y
  1940. ---help---
  1941. Find out whether you have a PCI motherboard. PCI is the name of a
  1942. bus system, i.e. the way the CPU talks to the other stuff inside
  1943. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1944. VESA. If you have PCI, say Y, otherwise N.
  1945. choice
  1946. prompt "PCI access mode"
  1947. depends on X86_32 && PCI
  1948. default PCI_GOANY
  1949. ---help---
  1950. On PCI systems, the BIOS can be used to detect the PCI devices and
  1951. determine their configuration. However, some old PCI motherboards
  1952. have BIOS bugs and may crash if this is done. Also, some embedded
  1953. PCI-based systems don't have any BIOS at all. Linux can also try to
  1954. detect the PCI hardware directly without using the BIOS.
  1955. With this option, you can specify how Linux should detect the
  1956. PCI devices. If you choose "BIOS", the BIOS will be used,
  1957. if you choose "Direct", the BIOS won't be used, and if you
  1958. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1959. If you choose "Any", the kernel will try MMCONFIG, then the
  1960. direct access method and falls back to the BIOS if that doesn't
  1961. work. If unsure, go with the default, which is "Any".
  1962. config PCI_GOBIOS
  1963. bool "BIOS"
  1964. config PCI_GOMMCONFIG
  1965. bool "MMConfig"
  1966. config PCI_GODIRECT
  1967. bool "Direct"
  1968. config PCI_GOOLPC
  1969. bool "OLPC XO-1"
  1970. depends on OLPC
  1971. config PCI_GOANY
  1972. bool "Any"
  1973. endchoice
  1974. config PCI_BIOS
  1975. def_bool y
  1976. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1977. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1978. config PCI_DIRECT
  1979. def_bool y
  1980. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  1981. config PCI_MMCONFIG
  1982. def_bool y
  1983. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1984. config PCI_OLPC
  1985. def_bool y
  1986. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1987. config PCI_XEN
  1988. def_bool y
  1989. depends on PCI && XEN
  1990. select SWIOTLB_XEN
  1991. config PCI_DOMAINS
  1992. def_bool y
  1993. depends on PCI
  1994. config PCI_MMCONFIG
  1995. bool "Support mmconfig PCI config space access"
  1996. depends on X86_64 && PCI && ACPI
  1997. config PCI_CNB20LE_QUIRK
  1998. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1999. depends on PCI
  2000. help
  2001. Read the PCI windows out of the CNB20LE host bridge. This allows
  2002. PCI hotplug to work on systems with the CNB20LE chipset which do
  2003. not have ACPI.
  2004. There's no public spec for this chipset, and this functionality
  2005. is known to be incomplete.
  2006. You should say N unless you know you need this.
  2007. source "drivers/pci/pcie/Kconfig"
  2008. source "drivers/pci/Kconfig"
  2009. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2010. config ISA_DMA_API
  2011. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2012. default y
  2013. help
  2014. Enables ISA-style DMA support for devices requiring such controllers.
  2015. If unsure, say Y.
  2016. if X86_32
  2017. config ISA
  2018. bool "ISA support"
  2019. ---help---
  2020. Find out whether you have ISA slots on your motherboard. ISA is the
  2021. name of a bus system, i.e. the way the CPU talks to the other stuff
  2022. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2023. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2024. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2025. config EISA
  2026. bool "EISA support"
  2027. depends on ISA
  2028. ---help---
  2029. The Extended Industry Standard Architecture (EISA) bus was
  2030. developed as an open alternative to the IBM MicroChannel bus.
  2031. The EISA bus provided some of the features of the IBM MicroChannel
  2032. bus while maintaining backward compatibility with cards made for
  2033. the older ISA bus. The EISA bus saw limited use between 1988 and
  2034. 1995 when it was made obsolete by the PCI bus.
  2035. Say Y here if you are building a kernel for an EISA-based machine.
  2036. Otherwise, say N.
  2037. source "drivers/eisa/Kconfig"
  2038. config SCx200
  2039. tristate "NatSemi SCx200 support"
  2040. ---help---
  2041. This provides basic support for National Semiconductor's
  2042. (now AMD's) Geode processors. The driver probes for the
  2043. PCI-IDs of several on-chip devices, so its a good dependency
  2044. for other scx200_* drivers.
  2045. If compiled as a module, the driver is named scx200.
  2046. config SCx200HR_TIMER
  2047. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2048. depends on SCx200
  2049. default y
  2050. ---help---
  2051. This driver provides a clocksource built upon the on-chip
  2052. 27MHz high-resolution timer. Its also a workaround for
  2053. NSC Geode SC-1100's buggy TSC, which loses time when the
  2054. processor goes idle (as is done by the scheduler). The
  2055. other workaround is idle=poll boot option.
  2056. config OLPC
  2057. bool "One Laptop Per Child support"
  2058. depends on !X86_PAE
  2059. select GPIOLIB
  2060. select OF
  2061. select OF_PROMTREE
  2062. select IRQ_DOMAIN
  2063. ---help---
  2064. Add support for detecting the unique features of the OLPC
  2065. XO hardware.
  2066. config OLPC_XO1_PM
  2067. bool "OLPC XO-1 Power Management"
  2068. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2069. select MFD_CORE
  2070. ---help---
  2071. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2072. config OLPC_XO1_RTC
  2073. bool "OLPC XO-1 Real Time Clock"
  2074. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2075. ---help---
  2076. Add support for the XO-1 real time clock, which can be used as a
  2077. programmable wakeup source.
  2078. config OLPC_XO1_SCI
  2079. bool "OLPC XO-1 SCI extras"
  2080. depends on OLPC && OLPC_XO1_PM
  2081. depends on INPUT=y
  2082. select POWER_SUPPLY
  2083. select GPIO_CS5535
  2084. select MFD_CORE
  2085. ---help---
  2086. Add support for SCI-based features of the OLPC XO-1 laptop:
  2087. - EC-driven system wakeups
  2088. - Power button
  2089. - Ebook switch
  2090. - Lid switch
  2091. - AC adapter status updates
  2092. - Battery status updates
  2093. config OLPC_XO15_SCI
  2094. bool "OLPC XO-1.5 SCI extras"
  2095. depends on OLPC && ACPI
  2096. select POWER_SUPPLY
  2097. ---help---
  2098. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2099. - EC-driven system wakeups
  2100. - AC adapter status updates
  2101. - Battery status updates
  2102. config ALIX
  2103. bool "PCEngines ALIX System Support (LED setup)"
  2104. select GPIOLIB
  2105. ---help---
  2106. This option enables system support for the PCEngines ALIX.
  2107. At present this just sets up LEDs for GPIO control on
  2108. ALIX2/3/6 boards. However, other system specific setup should
  2109. get added here.
  2110. Note: You must still enable the drivers for GPIO and LED support
  2111. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2112. Note: You have to set alix.force=1 for boards with Award BIOS.
  2113. config NET5501
  2114. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2115. select GPIOLIB
  2116. ---help---
  2117. This option enables system support for the Soekris Engineering net5501.
  2118. config GEOS
  2119. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2120. select GPIOLIB
  2121. depends on DMI
  2122. ---help---
  2123. This option enables system support for the Traverse Technologies GEOS.
  2124. config TS5500
  2125. bool "Technologic Systems TS-5500 platform support"
  2126. depends on MELAN
  2127. select CHECK_SIGNATURE
  2128. select NEW_LEDS
  2129. select LEDS_CLASS
  2130. ---help---
  2131. This option enables system support for the Technologic Systems TS-5500.
  2132. endif # X86_32
  2133. config AMD_NB
  2134. def_bool y
  2135. depends on CPU_SUP_AMD && PCI
  2136. source "drivers/pcmcia/Kconfig"
  2137. source "drivers/pci/hotplug/Kconfig"
  2138. config RAPIDIO
  2139. tristate "RapidIO support"
  2140. depends on PCI
  2141. default n
  2142. help
  2143. If enabled this option will include drivers and the core
  2144. infrastructure code to support RapidIO interconnect devices.
  2145. source "drivers/rapidio/Kconfig"
  2146. config X86_SYSFB
  2147. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2148. help
  2149. Firmwares often provide initial graphics framebuffers so the BIOS,
  2150. bootloader or kernel can show basic video-output during boot for
  2151. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2152. Extensions and EFI-framebuffers for this, which are mostly limited
  2153. to x86.
  2154. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2155. framebuffers so the new generic system-framebuffer drivers can be
  2156. used on x86. If the framebuffer is not compatible with the generic
  2157. modes, it is adverticed as fallback platform framebuffer so legacy
  2158. drivers like efifb, vesafb and uvesafb can pick it up.
  2159. If this option is not selected, all system framebuffers are always
  2160. marked as fallback platform framebuffers as usual.
  2161. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2162. not be able to pick up generic system framebuffers if this option
  2163. is selected. You are highly encouraged to enable simplefb as
  2164. replacement if you select this option. simplefb can correctly deal
  2165. with generic system framebuffers. But you should still keep vesafb
  2166. and others enabled as fallback if a system framebuffer is
  2167. incompatible with simplefb.
  2168. If unsure, say Y.
  2169. endmenu
  2170. menu "Executable file formats / Emulations"
  2171. source "fs/Kconfig.binfmt"
  2172. config IA32_EMULATION
  2173. bool "IA32 Emulation"
  2174. depends on X86_64
  2175. select BINFMT_ELF
  2176. select COMPAT_BINFMT_ELF
  2177. select ARCH_WANT_OLD_COMPAT_IPC
  2178. ---help---
  2179. Include code to run legacy 32-bit programs under a
  2180. 64-bit kernel. You should likely turn this on, unless you're
  2181. 100% sure that you don't have any 32-bit programs left.
  2182. config IA32_AOUT
  2183. tristate "IA32 a.out support"
  2184. depends on IA32_EMULATION
  2185. ---help---
  2186. Support old a.out binaries in the 32bit emulation.
  2187. config X86_X32
  2188. bool "x32 ABI for 64-bit mode"
  2189. depends on X86_64
  2190. ---help---
  2191. Include code to run binaries for the x32 native 32-bit ABI
  2192. for 64-bit processors. An x32 process gets access to the
  2193. full 64-bit register file and wide data path while leaving
  2194. pointers at 32 bits for smaller memory footprint.
  2195. You will need a recent binutils (2.22 or later) with
  2196. elf32_x86_64 support enabled to compile a kernel with this
  2197. option set.
  2198. config COMPAT
  2199. def_bool y
  2200. depends on IA32_EMULATION || X86_X32
  2201. if COMPAT
  2202. config COMPAT_FOR_U64_ALIGNMENT
  2203. def_bool y
  2204. config SYSVIPC_COMPAT
  2205. def_bool y
  2206. depends on SYSVIPC
  2207. config KEYS_COMPAT
  2208. def_bool y
  2209. depends on KEYS
  2210. endif
  2211. endmenu
  2212. config HAVE_ATOMIC_IOMAP
  2213. def_bool y
  2214. depends on X86_32
  2215. config X86_DEV_DMA_OPS
  2216. bool
  2217. depends on X86_64 || STA2X11
  2218. config X86_DMA_REMAP
  2219. bool
  2220. depends on STA2X11
  2221. config PMC_ATOM
  2222. def_bool y
  2223. depends on PCI
  2224. config VMD
  2225. depends on PCI_MSI
  2226. tristate "Volume Management Device Driver"
  2227. default N
  2228. ---help---
  2229. Adds support for the Intel Volume Management Device (VMD). VMD is a
  2230. secondary PCI host bridge that allows PCI Express root ports,
  2231. and devices attached to them, to be removed from the default
  2232. PCI domain and placed within the VMD domain. This provides
  2233. more bus resources than are otherwise possible with a
  2234. single domain. If you know your system provides one of these and
  2235. has devices attached to it, say Y; if you are not sure, say N.
  2236. source "net/Kconfig"
  2237. source "drivers/Kconfig"
  2238. source "drivers/firmware/Kconfig"
  2239. source "fs/Kconfig"
  2240. source "arch/x86/Kconfig.debug"
  2241. source "security/Kconfig"
  2242. source "crypto/Kconfig"
  2243. source "arch/x86/kvm/Kconfig"
  2244. source "lib/Kconfig"