Kconfig 88 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_DEVMEM_IS_ALLOWED
  25. select ARCH_HAS_ELF_RANDOMIZE
  26. select ARCH_HAS_FAST_MULTIPLIER
  27. select ARCH_HAS_GCOV_PROFILE_ALL
  28. select ARCH_HAS_KCOV if X86_64
  29. select ARCH_HAS_PMEM_API if X86_64
  30. select ARCH_HAS_MMIO_FLUSH
  31. select ARCH_HAS_SG_CHAIN
  32. select ARCH_HAS_UBSAN_SANITIZE_ALL
  33. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  34. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  35. select ARCH_MIGHT_HAVE_PC_PARPORT
  36. select ARCH_MIGHT_HAVE_PC_SERIO
  37. select ARCH_SUPPORTS_ATOMIC_RMW
  38. select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
  39. select ARCH_SUPPORTS_INT128 if X86_64
  40. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  41. select ARCH_USE_BUILTIN_BSWAP
  42. select ARCH_USE_CMPXCHG_LOCKREF if X86_64
  43. select ARCH_USE_QUEUED_RWLOCKS
  44. select ARCH_USE_QUEUED_SPINLOCKS
  45. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
  46. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  47. select ARCH_WANT_FRAME_POINTERS
  48. select ARCH_WANT_IPC_PARSE_VERSION if X86_32
  49. select ARCH_WANT_OPTIONAL_GPIOLIB
  50. select BUILDTIME_EXTABLE_SORT
  51. select CLKEVT_I8253
  52. select CLKSRC_I8253 if X86_32
  53. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  54. select CLOCKSOURCE_WATCHDOG
  55. select CLONE_BACKWARDS if X86_32
  56. select COMPAT_OLD_SIGACTION if IA32_EMULATION
  57. select DCACHE_WORD_ACCESS
  58. select EDAC_ATOMIC_SCRUB
  59. select EDAC_SUPPORT
  60. select GENERIC_CLOCKEVENTS
  61. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  62. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  63. select GENERIC_CMOS_UPDATE
  64. select GENERIC_CPU_AUTOPROBE
  65. select GENERIC_EARLY_IOREMAP
  66. select GENERIC_FIND_FIRST_BIT
  67. select GENERIC_IOMAP
  68. select GENERIC_IRQ_PROBE
  69. select GENERIC_IRQ_SHOW
  70. select GENERIC_PENDING_IRQ if SMP
  71. select GENERIC_SMP_IDLE_THREAD
  72. select GENERIC_STRNCPY_FROM_USER
  73. select GENERIC_STRNLEN_USER
  74. select GENERIC_TIME_VSYSCALL
  75. select HAVE_ACPI_APEI if ACPI
  76. select HAVE_ACPI_APEI_NMI if ACPI
  77. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  78. select HAVE_AOUT if X86_32
  79. select HAVE_ARCH_AUDITSYSCALL
  80. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  81. select HAVE_ARCH_JUMP_LABEL
  82. select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
  83. select HAVE_ARCH_KGDB
  84. select HAVE_ARCH_KMEMCHECK
  85. select HAVE_ARCH_MMAP_RND_BITS if MMU
  86. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
  87. select HAVE_ARCH_SECCOMP_FILTER
  88. select HAVE_ARCH_SOFT_DIRTY if X86_64
  89. select HAVE_ARCH_TRACEHOOK
  90. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  91. select HAVE_ARCH_WITHIN_STACK_FRAMES
  92. select HAVE_EBPF_JIT if X86_64
  93. select HAVE_CC_STACKPROTECTOR
  94. select HAVE_CMPXCHG_DOUBLE
  95. select HAVE_CMPXCHG_LOCAL
  96. select HAVE_CONTEXT_TRACKING if X86_64
  97. select HAVE_COPY_THREAD_TLS
  98. select HAVE_C_RECORDMCOUNT
  99. select HAVE_DEBUG_KMEMLEAK
  100. select HAVE_DEBUG_STACKOVERFLOW
  101. select HAVE_DMA_API_DEBUG
  102. select HAVE_DMA_CONTIGUOUS
  103. select HAVE_DYNAMIC_FTRACE
  104. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  105. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  106. select HAVE_EXIT_THREAD
  107. select HAVE_FENTRY if X86_64
  108. select HAVE_FTRACE_MCOUNT_RECORD
  109. select HAVE_FUNCTION_GRAPH_FP_TEST
  110. select HAVE_FUNCTION_GRAPH_TRACER
  111. select HAVE_FUNCTION_TRACER
  112. select HAVE_GENERIC_DMA_COHERENT if X86_32
  113. select HAVE_HW_BREAKPOINT
  114. select HAVE_IDE
  115. select HAVE_IOREMAP_PROT
  116. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  117. select HAVE_IRQ_TIME_ACCOUNTING
  118. select HAVE_KERNEL_BZIP2
  119. select HAVE_KERNEL_GZIP
  120. select HAVE_KERNEL_LZ4
  121. select HAVE_KERNEL_LZMA
  122. select HAVE_KERNEL_LZO
  123. select HAVE_KERNEL_XZ
  124. select HAVE_KPROBES
  125. select HAVE_KPROBES_ON_FTRACE
  126. select HAVE_KRETPROBES
  127. select HAVE_KVM
  128. select HAVE_LIVEPATCH if X86_64
  129. select HAVE_MEMBLOCK
  130. select HAVE_MEMBLOCK_NODE_MAP
  131. select HAVE_MIXED_BREAKPOINTS_REGS
  132. select HAVE_NMI
  133. select HAVE_OPROFILE
  134. select HAVE_OPTPROBES
  135. select HAVE_PCSPKR_PLATFORM
  136. select HAVE_PERF_EVENTS
  137. select HAVE_PERF_EVENTS_NMI
  138. select HAVE_PERF_REGS
  139. select HAVE_PERF_USER_STACK_DUMP
  140. select HAVE_REGS_AND_STACK_ACCESS_API
  141. select HAVE_SYSCALL_TRACEPOINTS
  142. select HAVE_UID16 if X86_32 || IA32_EMULATION
  143. select HAVE_UNSTABLE_SCHED_CLOCK
  144. select HAVE_USER_RETURN_NOTIFIER
  145. select IRQ_FORCED_THREADING
  146. select MODULES_USE_ELF_RELA if X86_64
  147. select MODULES_USE_ELF_REL if X86_32
  148. select OLD_SIGACTION if X86_32
  149. select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
  150. select PERF_EVENTS
  151. select RTC_LIB
  152. select SPARSE_IRQ
  153. select SRCU
  154. select SYSCTL_EXCEPTION_TRACE
  155. select USER_STACKTRACE_SUPPORT
  156. select VIRT_TO_BUS
  157. select X86_DEV_DMA_OPS if X86_64
  158. select X86_FEATURE_NAMES if PROC_FS
  159. select HAVE_STACK_VALIDATION if X86_64
  160. select ARCH_USES_HIGH_VMA_FLAGS if X86_INTEL_MEMORY_PROTECTION_KEYS
  161. select ARCH_HAS_PKEYS if X86_INTEL_MEMORY_PROTECTION_KEYS
  162. config INSTRUCTION_DECODER
  163. def_bool y
  164. depends on KPROBES || PERF_EVENTS || UPROBES
  165. config OUTPUT_FORMAT
  166. string
  167. default "elf32-i386" if X86_32
  168. default "elf64-x86-64" if X86_64
  169. config ARCH_DEFCONFIG
  170. string
  171. default "arch/x86/configs/i386_defconfig" if X86_32
  172. default "arch/x86/configs/x86_64_defconfig" if X86_64
  173. config LOCKDEP_SUPPORT
  174. def_bool y
  175. config STACKTRACE_SUPPORT
  176. def_bool y
  177. config MMU
  178. def_bool y
  179. config ARCH_MMAP_RND_BITS_MIN
  180. default 28 if 64BIT
  181. default 8
  182. config ARCH_MMAP_RND_BITS_MAX
  183. default 32 if 64BIT
  184. default 16
  185. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  186. default 8
  187. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  188. default 16
  189. config SBUS
  190. bool
  191. config NEED_DMA_MAP_STATE
  192. def_bool y
  193. depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
  194. config NEED_SG_DMA_LENGTH
  195. def_bool y
  196. config GENERIC_ISA_DMA
  197. def_bool y
  198. depends on ISA_DMA_API
  199. config GENERIC_BUG
  200. def_bool y
  201. depends on BUG
  202. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  203. config GENERIC_BUG_RELATIVE_POINTERS
  204. bool
  205. config GENERIC_HWEIGHT
  206. def_bool y
  207. config ARCH_MAY_HAVE_PC_FDC
  208. def_bool y
  209. depends on ISA_DMA_API
  210. config RWSEM_XCHGADD_ALGORITHM
  211. def_bool y
  212. config GENERIC_CALIBRATE_DELAY
  213. def_bool y
  214. config ARCH_HAS_CPU_RELAX
  215. def_bool y
  216. config ARCH_HAS_CACHE_LINE_SIZE
  217. def_bool y
  218. config HAVE_SETUP_PER_CPU_AREA
  219. def_bool y
  220. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  221. def_bool y
  222. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  223. def_bool y
  224. config ARCH_HIBERNATION_POSSIBLE
  225. def_bool y
  226. config ARCH_SUSPEND_POSSIBLE
  227. def_bool y
  228. config ARCH_WANT_HUGE_PMD_SHARE
  229. def_bool y
  230. config ARCH_WANT_GENERAL_HUGETLB
  231. def_bool y
  232. config ZONE_DMA32
  233. def_bool y if X86_64
  234. config AUDIT_ARCH
  235. def_bool y if X86_64
  236. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  237. def_bool y
  238. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  239. def_bool y
  240. config KASAN_SHADOW_OFFSET
  241. hex
  242. depends on KASAN
  243. default 0xdffffc0000000000
  244. config HAVE_INTEL_TXT
  245. def_bool y
  246. depends on INTEL_IOMMU && ACPI
  247. config X86_32_SMP
  248. def_bool y
  249. depends on X86_32 && SMP
  250. config X86_64_SMP
  251. def_bool y
  252. depends on X86_64 && SMP
  253. config X86_32_LAZY_GS
  254. def_bool y
  255. depends on X86_32 && !CC_STACKPROTECTOR
  256. config ARCH_HWEIGHT_CFLAGS
  257. string
  258. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  259. 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
  260. config ARCH_SUPPORTS_UPROBES
  261. def_bool y
  262. config FIX_EARLYCON_MEM
  263. def_bool y
  264. config DEBUG_RODATA
  265. def_bool y
  266. config PGTABLE_LEVELS
  267. int
  268. default 4 if X86_64
  269. default 3 if X86_PAE
  270. default 2
  271. source "init/Kconfig"
  272. source "kernel/Kconfig.freezer"
  273. menu "Processor type and features"
  274. config ZONE_DMA
  275. bool "DMA memory allocation support" if EXPERT
  276. default y
  277. help
  278. DMA memory allocation support allows devices with less than 32-bit
  279. addressing to allocate within the first 16MB of address space.
  280. Disable if no such devices will be used.
  281. If unsure, say Y.
  282. config SMP
  283. bool "Symmetric multi-processing support"
  284. ---help---
  285. This enables support for systems with more than one CPU. If you have
  286. a system with only one CPU, say N. If you have a system with more
  287. than one CPU, say Y.
  288. If you say N here, the kernel will run on uni- and multiprocessor
  289. machines, but will use only one CPU of a multiprocessor machine. If
  290. you say Y here, the kernel will run on many, but not all,
  291. uniprocessor machines. On a uniprocessor machine, the kernel
  292. will run faster if you say N here.
  293. Note that if you say Y here and choose architecture "586" or
  294. "Pentium" under "Processor family", the kernel will not work on 486
  295. architectures. Similarly, multiprocessor kernels for the "PPro"
  296. architecture may not work on all Pentium based boards.
  297. People using multiprocessor machines who say Y here should also say
  298. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  299. Management" code will be disabled if you say Y here.
  300. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  301. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  302. <http://www.tldp.org/docs.html#howto>.
  303. If you don't know what to do here, say N.
  304. config X86_FEATURE_NAMES
  305. bool "Processor feature human-readable names" if EMBEDDED
  306. default y
  307. ---help---
  308. This option compiles in a table of x86 feature bits and corresponding
  309. names. This is required to support /proc/cpuinfo and a few kernel
  310. messages. You can disable this to save space, at the expense of
  311. making those few kernel messages show numeric feature bits instead.
  312. If in doubt, say Y.
  313. config X86_FAST_FEATURE_TESTS
  314. bool "Fast CPU feature tests" if EMBEDDED
  315. default y
  316. ---help---
  317. Some fast-paths in the kernel depend on the capabilities of the CPU.
  318. Say Y here for the kernel to patch in the appropriate code at runtime
  319. based on the capabilities of the CPU. The infrastructure for patching
  320. code at runtime takes up some additional space; space-constrained
  321. embedded systems may wish to say N here to produce smaller, slightly
  322. slower code.
  323. config X86_X2APIC
  324. bool "Support x2apic"
  325. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  326. ---help---
  327. This enables x2apic support on CPUs that have this feature.
  328. This allows 32-bit apic IDs (so it can support very large systems),
  329. and accesses the local apic via MSRs not via mmio.
  330. If you don't know what to do here, say N.
  331. config X86_MPPARSE
  332. bool "Enable MPS table" if ACPI || SFI
  333. default y
  334. depends on X86_LOCAL_APIC
  335. ---help---
  336. For old smp systems that do not have proper acpi support. Newer systems
  337. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  338. config X86_BIGSMP
  339. bool "Support for big SMP systems with more than 8 CPUs"
  340. depends on X86_32 && SMP
  341. ---help---
  342. This option is needed for the systems that have more than 8 CPUs
  343. config GOLDFISH
  344. def_bool y
  345. depends on X86_GOLDFISH
  346. if X86_32
  347. config X86_EXTENDED_PLATFORM
  348. bool "Support for extended (non-PC) x86 platforms"
  349. default y
  350. ---help---
  351. If you disable this option then the kernel will only support
  352. standard PC platforms. (which covers the vast majority of
  353. systems out there.)
  354. If you enable this option then you'll be able to select support
  355. for the following (non-PC) 32 bit x86 platforms:
  356. Goldfish (Android emulator)
  357. AMD Elan
  358. RDC R-321x SoC
  359. SGI 320/540 (Visual Workstation)
  360. STA2X11-based (e.g. Northville)
  361. Moorestown MID devices
  362. If you have one of these systems, or if you want to build a
  363. generic distribution kernel, say Y here - otherwise say N.
  364. endif
  365. if X86_64
  366. config X86_EXTENDED_PLATFORM
  367. bool "Support for extended (non-PC) x86 platforms"
  368. default y
  369. ---help---
  370. If you disable this option then the kernel will only support
  371. standard PC platforms. (which covers the vast majority of
  372. systems out there.)
  373. If you enable this option then you'll be able to select support
  374. for the following (non-PC) 64 bit x86 platforms:
  375. Numascale NumaChip
  376. ScaleMP vSMP
  377. SGI Ultraviolet
  378. If you have one of these systems, or if you want to build a
  379. generic distribution kernel, say Y here - otherwise say N.
  380. endif
  381. # This is an alphabetically sorted list of 64 bit extended platforms
  382. # Please maintain the alphabetic order if and when there are additions
  383. config X86_NUMACHIP
  384. bool "Numascale NumaChip"
  385. depends on X86_64
  386. depends on X86_EXTENDED_PLATFORM
  387. depends on NUMA
  388. depends on SMP
  389. depends on X86_X2APIC
  390. depends on PCI_MMCONFIG
  391. ---help---
  392. Adds support for Numascale NumaChip large-SMP systems. Needed to
  393. enable more than ~168 cores.
  394. If you don't have one of these, you should say N here.
  395. config X86_VSMP
  396. bool "ScaleMP vSMP"
  397. select HYPERVISOR_GUEST
  398. select PARAVIRT
  399. depends on X86_64 && PCI
  400. depends on X86_EXTENDED_PLATFORM
  401. depends on SMP
  402. ---help---
  403. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  404. supposed to run on these EM64T-based machines. Only choose this option
  405. if you have one of these machines.
  406. config X86_UV
  407. bool "SGI Ultraviolet"
  408. depends on X86_64
  409. depends on X86_EXTENDED_PLATFORM
  410. depends on NUMA
  411. depends on EFI
  412. depends on X86_X2APIC
  413. depends on PCI
  414. ---help---
  415. This option is needed in order to support SGI Ultraviolet systems.
  416. If you don't have one of these, you should say N here.
  417. # Following is an alphabetically sorted list of 32 bit extended platforms
  418. # Please maintain the alphabetic order if and when there are additions
  419. config X86_GOLDFISH
  420. bool "Goldfish (Virtual Platform)"
  421. depends on X86_EXTENDED_PLATFORM
  422. ---help---
  423. Enable support for the Goldfish virtual platform used primarily
  424. for Android development. Unless you are building for the Android
  425. Goldfish emulator say N here.
  426. config X86_INTEL_CE
  427. bool "CE4100 TV platform"
  428. depends on PCI
  429. depends on PCI_GODIRECT
  430. depends on X86_IO_APIC
  431. depends on X86_32
  432. depends on X86_EXTENDED_PLATFORM
  433. select X86_REBOOTFIXUPS
  434. select OF
  435. select OF_EARLY_FLATTREE
  436. ---help---
  437. Select for the Intel CE media processor (CE4100) SOC.
  438. This option compiles in support for the CE4100 SOC for settop
  439. boxes and media devices.
  440. config X86_INTEL_MID
  441. bool "Intel MID platform support"
  442. depends on X86_EXTENDED_PLATFORM
  443. depends on X86_PLATFORM_DEVICES
  444. depends on PCI
  445. depends on X86_64 || (PCI_GOANY && X86_32)
  446. depends on X86_IO_APIC
  447. select SFI
  448. select I2C
  449. select DW_APB_TIMER
  450. select APB_TIMER
  451. select INTEL_SCU_IPC
  452. select MFD_INTEL_MSIC
  453. ---help---
  454. Select to build a kernel capable of supporting Intel MID (Mobile
  455. Internet Device) platform systems which do not have the PCI legacy
  456. interfaces. If you are building for a PC class system say N here.
  457. Intel MID platforms are based on an Intel processor and chipset which
  458. consume less power than most of the x86 derivatives.
  459. config X86_INTEL_QUARK
  460. bool "Intel Quark platform support"
  461. depends on X86_32
  462. depends on X86_EXTENDED_PLATFORM
  463. depends on X86_PLATFORM_DEVICES
  464. depends on X86_TSC
  465. depends on PCI
  466. depends on PCI_GOANY
  467. depends on X86_IO_APIC
  468. select IOSF_MBI
  469. select INTEL_IMR
  470. select COMMON_CLK
  471. ---help---
  472. Select to include support for Quark X1000 SoC.
  473. Say Y here if you have a Quark based system such as the Arduino
  474. compatible Intel Galileo.
  475. config X86_INTEL_LPSS
  476. bool "Intel Low Power Subsystem Support"
  477. depends on X86 && ACPI
  478. select COMMON_CLK
  479. select PINCTRL
  480. select IOSF_MBI
  481. ---help---
  482. Select to build support for Intel Low Power Subsystem such as
  483. found on Intel Lynxpoint PCH. Selecting this option enables
  484. things like clock tree (common clock framework) and pincontrol
  485. which are needed by the LPSS peripheral drivers.
  486. config X86_AMD_PLATFORM_DEVICE
  487. bool "AMD ACPI2Platform devices support"
  488. depends on ACPI
  489. select COMMON_CLK
  490. select PINCTRL
  491. ---help---
  492. Select to interpret AMD specific ACPI device to platform device
  493. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  494. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  495. implemented under PINCTRL subsystem.
  496. config IOSF_MBI
  497. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  498. depends on PCI
  499. ---help---
  500. This option enables sideband register access support for Intel SoC
  501. platforms. On these platforms the IOSF sideband is used in lieu of
  502. MSR's for some register accesses, mostly but not limited to thermal
  503. and power. Drivers may query the availability of this device to
  504. determine if they need the sideband in order to work on these
  505. platforms. The sideband is available on the following SoC products.
  506. This list is not meant to be exclusive.
  507. - BayTrail
  508. - Braswell
  509. - Quark
  510. You should say Y if you are running a kernel on one of these SoC's.
  511. config IOSF_MBI_DEBUG
  512. bool "Enable IOSF sideband access through debugfs"
  513. depends on IOSF_MBI && DEBUG_FS
  514. ---help---
  515. Select this option to expose the IOSF sideband access registers (MCR,
  516. MDR, MCRX) through debugfs to write and read register information from
  517. different units on the SoC. This is most useful for obtaining device
  518. state information for debug and analysis. As this is a general access
  519. mechanism, users of this option would have specific knowledge of the
  520. device they want to access.
  521. If you don't require the option or are in doubt, say N.
  522. config X86_RDC321X
  523. bool "RDC R-321x SoC"
  524. depends on X86_32
  525. depends on X86_EXTENDED_PLATFORM
  526. select M486
  527. select X86_REBOOTFIXUPS
  528. ---help---
  529. This option is needed for RDC R-321x system-on-chip, also known
  530. as R-8610-(G).
  531. If you don't have one of these chips, you should say N here.
  532. config X86_32_NON_STANDARD
  533. bool "Support non-standard 32-bit SMP architectures"
  534. depends on X86_32 && SMP
  535. depends on X86_EXTENDED_PLATFORM
  536. ---help---
  537. This option compiles in the bigsmp and STA2X11 default
  538. subarchitectures. It is intended for a generic binary
  539. kernel. If you select them all, kernel will probe it one by
  540. one and will fallback to default.
  541. # Alphabetically sorted list of Non standard 32 bit platforms
  542. config X86_SUPPORTS_MEMORY_FAILURE
  543. def_bool y
  544. # MCE code calls memory_failure():
  545. depends on X86_MCE
  546. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  547. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  548. depends on X86_64 || !SPARSEMEM
  549. select ARCH_SUPPORTS_MEMORY_FAILURE
  550. config STA2X11
  551. bool "STA2X11 Companion Chip Support"
  552. depends on X86_32_NON_STANDARD && PCI
  553. select X86_DEV_DMA_OPS
  554. select X86_DMA_REMAP
  555. select SWIOTLB
  556. select MFD_STA2X11
  557. select ARCH_REQUIRE_GPIOLIB
  558. default n
  559. ---help---
  560. This adds support for boards based on the STA2X11 IO-Hub,
  561. a.k.a. "ConneXt". The chip is used in place of the standard
  562. PC chipset, so all "standard" peripherals are missing. If this
  563. option is selected the kernel will still be able to boot on
  564. standard PC machines.
  565. config X86_32_IRIS
  566. tristate "Eurobraille/Iris poweroff module"
  567. depends on X86_32
  568. ---help---
  569. The Iris machines from EuroBraille do not have APM or ACPI support
  570. to shut themselves down properly. A special I/O sequence is
  571. needed to do so, which is what this module does at
  572. kernel shutdown.
  573. This is only for Iris machines from EuroBraille.
  574. If unused, say N.
  575. config SCHED_OMIT_FRAME_POINTER
  576. def_bool y
  577. prompt "Single-depth WCHAN output"
  578. depends on X86
  579. ---help---
  580. Calculate simpler /proc/<PID>/wchan values. If this option
  581. is disabled then wchan values will recurse back to the
  582. caller function. This provides more accurate wchan values,
  583. at the expense of slightly more scheduling overhead.
  584. If in doubt, say "Y".
  585. menuconfig HYPERVISOR_GUEST
  586. bool "Linux guest support"
  587. ---help---
  588. Say Y here to enable options for running Linux under various hyper-
  589. visors. This option enables basic hypervisor detection and platform
  590. setup.
  591. If you say N, all options in this submenu will be skipped and
  592. disabled, and Linux guest support won't be built in.
  593. if HYPERVISOR_GUEST
  594. config PARAVIRT
  595. bool "Enable paravirtualization code"
  596. ---help---
  597. This changes the kernel so it can modify itself when it is run
  598. under a hypervisor, potentially improving performance significantly
  599. over full virtualization. However, when run without a hypervisor
  600. the kernel is theoretically slower and slightly larger.
  601. config PARAVIRT_DEBUG
  602. bool "paravirt-ops debugging"
  603. depends on PARAVIRT && DEBUG_KERNEL
  604. ---help---
  605. Enable to debug paravirt_ops internals. Specifically, BUG if
  606. a paravirt_op is missing when it is called.
  607. config PARAVIRT_SPINLOCKS
  608. bool "Paravirtualization layer for spinlocks"
  609. depends on PARAVIRT && SMP
  610. select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
  611. ---help---
  612. Paravirtualized spinlocks allow a pvops backend to replace the
  613. spinlock implementation with something virtualization-friendly
  614. (for example, block the virtual CPU rather than spinning).
  615. It has a minimal impact on native kernels and gives a nice performance
  616. benefit on paravirtualized KVM / Xen kernels.
  617. If you are unsure how to answer this question, answer Y.
  618. config QUEUED_LOCK_STAT
  619. bool "Paravirt queued spinlock statistics"
  620. depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS
  621. ---help---
  622. Enable the collection of statistical data on the slowpath
  623. behavior of paravirtualized queued spinlocks and report
  624. them on debugfs.
  625. source "arch/x86/xen/Kconfig"
  626. config KVM_GUEST
  627. bool "KVM Guest support (including kvmclock)"
  628. depends on PARAVIRT
  629. select PARAVIRT_CLOCK
  630. default y
  631. ---help---
  632. This option enables various optimizations for running under the KVM
  633. hypervisor. It includes a paravirtualized clock, so that instead
  634. of relying on a PIT (or probably other) emulation by the
  635. underlying device model, the host provides the guest with
  636. timing infrastructure such as time of day, and system time
  637. config KVM_DEBUG_FS
  638. bool "Enable debug information for KVM Guests in debugfs"
  639. depends on KVM_GUEST && DEBUG_FS
  640. default n
  641. ---help---
  642. This option enables collection of various statistics for KVM guest.
  643. Statistics are displayed in debugfs filesystem. Enabling this option
  644. may incur significant overhead.
  645. source "arch/x86/lguest/Kconfig"
  646. config PARAVIRT_TIME_ACCOUNTING
  647. bool "Paravirtual steal time accounting"
  648. depends on PARAVIRT
  649. default n
  650. ---help---
  651. Select this option to enable fine granularity task steal time
  652. accounting. Time spent executing other tasks in parallel with
  653. the current vCPU is discounted from the vCPU power. To account for
  654. that, there can be a small performance impact.
  655. If in doubt, say N here.
  656. config PARAVIRT_CLOCK
  657. bool
  658. endif #HYPERVISOR_GUEST
  659. config NO_BOOTMEM
  660. def_bool y
  661. source "arch/x86/Kconfig.cpu"
  662. config HPET_TIMER
  663. def_bool X86_64
  664. prompt "HPET Timer Support" if X86_32
  665. ---help---
  666. Use the IA-PC HPET (High Precision Event Timer) to manage
  667. time in preference to the PIT and RTC, if a HPET is
  668. present.
  669. HPET is the next generation timer replacing legacy 8254s.
  670. The HPET provides a stable time base on SMP
  671. systems, unlike the TSC, but it is more expensive to access,
  672. as it is off-chip. The interface used is documented
  673. in the HPET spec, revision 1.
  674. You can safely choose Y here. However, HPET will only be
  675. activated if the platform and the BIOS support this feature.
  676. Otherwise the 8254 will be used for timing services.
  677. Choose N to continue using the legacy 8254 timer.
  678. config HPET_EMULATE_RTC
  679. def_bool y
  680. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  681. config APB_TIMER
  682. def_bool y if X86_INTEL_MID
  683. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  684. select DW_APB_TIMER
  685. depends on X86_INTEL_MID && SFI
  686. help
  687. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  688. The APBT provides a stable time base on SMP
  689. systems, unlike the TSC, but it is more expensive to access,
  690. as it is off-chip. APB timers are always running regardless of CPU
  691. C states, they are used as per CPU clockevent device when possible.
  692. # Mark as expert because too many people got it wrong.
  693. # The code disables itself when not needed.
  694. config DMI
  695. default y
  696. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  697. bool "Enable DMI scanning" if EXPERT
  698. ---help---
  699. Enabled scanning of DMI to identify machine quirks. Say Y
  700. here unless you have verified that your setup is not
  701. affected by entries in the DMI blacklist. Required by PNP
  702. BIOS code.
  703. config GART_IOMMU
  704. bool "Old AMD GART IOMMU support"
  705. select SWIOTLB
  706. depends on X86_64 && PCI && AMD_NB
  707. ---help---
  708. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  709. GART based hardware IOMMUs.
  710. The GART supports full DMA access for devices with 32-bit access
  711. limitations, on systems with more than 3 GB. This is usually needed
  712. for USB, sound, many IDE/SATA chipsets and some other devices.
  713. Newer systems typically have a modern AMD IOMMU, supported via
  714. the CONFIG_AMD_IOMMU=y config option.
  715. In normal configurations this driver is only active when needed:
  716. there's more than 3 GB of memory and the system contains a
  717. 32-bit limited device.
  718. If unsure, say Y.
  719. config CALGARY_IOMMU
  720. bool "IBM Calgary IOMMU support"
  721. select SWIOTLB
  722. depends on X86_64 && PCI
  723. ---help---
  724. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  725. systems. Needed to run systems with more than 3GB of memory
  726. properly with 32-bit PCI devices that do not support DAC
  727. (Double Address Cycle). Calgary also supports bus level
  728. isolation, where all DMAs pass through the IOMMU. This
  729. prevents them from going anywhere except their intended
  730. destination. This catches hard-to-find kernel bugs and
  731. mis-behaving drivers and devices that do not use the DMA-API
  732. properly to set up their DMA buffers. The IOMMU can be
  733. turned off at boot time with the iommu=off parameter.
  734. Normally the kernel will make the right choice by itself.
  735. If unsure, say Y.
  736. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  737. def_bool y
  738. prompt "Should Calgary be enabled by default?"
  739. depends on CALGARY_IOMMU
  740. ---help---
  741. Should Calgary be enabled by default? if you choose 'y', Calgary
  742. will be used (if it exists). If you choose 'n', Calgary will not be
  743. used even if it exists. If you choose 'n' and would like to use
  744. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  745. If unsure, say Y.
  746. # need this always selected by IOMMU for the VIA workaround
  747. config SWIOTLB
  748. def_bool y if X86_64
  749. ---help---
  750. Support for software bounce buffers used on x86-64 systems
  751. which don't have a hardware IOMMU. Using this PCI devices
  752. which can only access 32-bits of memory can be used on systems
  753. with more than 3 GB of memory.
  754. If unsure, say Y.
  755. config IOMMU_HELPER
  756. def_bool y
  757. depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
  758. config MAXSMP
  759. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  760. depends on X86_64 && SMP && DEBUG_KERNEL
  761. select CPUMASK_OFFSTACK
  762. ---help---
  763. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  764. If unsure, say N.
  765. config NR_CPUS
  766. int "Maximum number of CPUs" if SMP && !MAXSMP
  767. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  768. range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
  769. range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
  770. default "1" if !SMP
  771. default "8192" if MAXSMP
  772. default "32" if SMP && X86_BIGSMP
  773. default "8" if SMP && X86_32
  774. default "64" if SMP
  775. ---help---
  776. This allows you to specify the maximum number of CPUs which this
  777. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  778. supported value is 8192, otherwise the maximum value is 512. The
  779. minimum value which makes sense is 2.
  780. This is purely to save memory - each supported CPU adds
  781. approximately eight kilobytes to the kernel image.
  782. config SCHED_SMT
  783. bool "SMT (Hyperthreading) scheduler support"
  784. depends on SMP
  785. ---help---
  786. SMT scheduler support improves the CPU scheduler's decision making
  787. when dealing with Intel Pentium 4 chips with HyperThreading at a
  788. cost of slightly increased overhead in some places. If unsure say
  789. N here.
  790. config SCHED_MC
  791. def_bool y
  792. prompt "Multi-core scheduler support"
  793. depends on SMP
  794. ---help---
  795. Multi-core scheduler support improves the CPU scheduler's decision
  796. making when dealing with multi-core CPU chips at a cost of slightly
  797. increased overhead in some places. If unsure say N here.
  798. source "kernel/Kconfig.preempt"
  799. config UP_LATE_INIT
  800. def_bool y
  801. depends on !SMP && X86_LOCAL_APIC
  802. config X86_UP_APIC
  803. bool "Local APIC support on uniprocessors" if !PCI_MSI
  804. default PCI_MSI
  805. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  806. ---help---
  807. A local APIC (Advanced Programmable Interrupt Controller) is an
  808. integrated interrupt controller in the CPU. If you have a single-CPU
  809. system which has a processor with a local APIC, you can say Y here to
  810. enable and use it. If you say Y here even though your machine doesn't
  811. have a local APIC, then the kernel will still run with no slowdown at
  812. all. The local APIC supports CPU-generated self-interrupts (timer,
  813. performance counters), and the NMI watchdog which detects hard
  814. lockups.
  815. config X86_UP_IOAPIC
  816. bool "IO-APIC support on uniprocessors"
  817. depends on X86_UP_APIC
  818. ---help---
  819. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  820. SMP-capable replacement for PC-style interrupt controllers. Most
  821. SMP systems and many recent uniprocessor systems have one.
  822. If you have a single-CPU system with an IO-APIC, you can say Y here
  823. to use it. If you say Y here even though your machine doesn't have
  824. an IO-APIC, then the kernel will still run with no slowdown at all.
  825. config X86_LOCAL_APIC
  826. def_bool y
  827. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  828. select IRQ_DOMAIN_HIERARCHY
  829. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  830. config X86_IO_APIC
  831. def_bool y
  832. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  833. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  834. bool "Reroute for broken boot IRQs"
  835. depends on X86_IO_APIC
  836. ---help---
  837. This option enables a workaround that fixes a source of
  838. spurious interrupts. This is recommended when threaded
  839. interrupt handling is used on systems where the generation of
  840. superfluous "boot interrupts" cannot be disabled.
  841. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  842. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  843. kernel does during interrupt handling). On chipsets where this
  844. boot IRQ generation cannot be disabled, this workaround keeps
  845. the original IRQ line masked so that only the equivalent "boot
  846. IRQ" is delivered to the CPUs. The workaround also tells the
  847. kernel to set up the IRQ handler on the boot IRQ line. In this
  848. way only one interrupt is delivered to the kernel. Otherwise
  849. the spurious second interrupt may cause the kernel to bring
  850. down (vital) interrupt lines.
  851. Only affects "broken" chipsets. Interrupt sharing may be
  852. increased on these systems.
  853. config X86_MCE
  854. bool "Machine Check / overheating reporting"
  855. select GENERIC_ALLOCATOR
  856. default y
  857. ---help---
  858. Machine Check support allows the processor to notify the
  859. kernel if it detects a problem (e.g. overheating, data corruption).
  860. The action the kernel takes depends on the severity of the problem,
  861. ranging from warning messages to halting the machine.
  862. config X86_MCE_INTEL
  863. def_bool y
  864. prompt "Intel MCE features"
  865. depends on X86_MCE && X86_LOCAL_APIC
  866. ---help---
  867. Additional support for intel specific MCE features such as
  868. the thermal monitor.
  869. config X86_MCE_AMD
  870. def_bool y
  871. prompt "AMD MCE features"
  872. depends on X86_MCE && X86_LOCAL_APIC
  873. ---help---
  874. Additional support for AMD specific MCE features such as
  875. the DRAM Error Threshold.
  876. config X86_ANCIENT_MCE
  877. bool "Support for old Pentium 5 / WinChip machine checks"
  878. depends on X86_32 && X86_MCE
  879. ---help---
  880. Include support for machine check handling on old Pentium 5 or WinChip
  881. systems. These typically need to be enabled explicitly on the command
  882. line.
  883. config X86_MCE_THRESHOLD
  884. depends on X86_MCE_AMD || X86_MCE_INTEL
  885. def_bool y
  886. config X86_MCE_INJECT
  887. depends on X86_MCE
  888. tristate "Machine check injector support"
  889. ---help---
  890. Provide support for injecting machine checks for testing purposes.
  891. If you don't know what a machine check is and you don't do kernel
  892. QA it is safe to say n.
  893. config X86_THERMAL_VECTOR
  894. def_bool y
  895. depends on X86_MCE_INTEL
  896. source "arch/x86/events/Kconfig"
  897. config X86_LEGACY_VM86
  898. bool "Legacy VM86 support"
  899. default n
  900. depends on X86_32
  901. ---help---
  902. This option allows user programs to put the CPU into V8086
  903. mode, which is an 80286-era approximation of 16-bit real mode.
  904. Some very old versions of X and/or vbetool require this option
  905. for user mode setting. Similarly, DOSEMU will use it if
  906. available to accelerate real mode DOS programs. However, any
  907. recent version of DOSEMU, X, or vbetool should be fully
  908. functional even without kernel VM86 support, as they will all
  909. fall back to software emulation. Nevertheless, if you are using
  910. a 16-bit DOS program where 16-bit performance matters, vm86
  911. mode might be faster than emulation and you might want to
  912. enable this option.
  913. Note that any app that works on a 64-bit kernel is unlikely to
  914. need this option, as 64-bit kernels don't, and can't, support
  915. V8086 mode. This option is also unrelated to 16-bit protected
  916. mode and is not needed to run most 16-bit programs under Wine.
  917. Enabling this option increases the complexity of the kernel
  918. and slows down exception handling a tiny bit.
  919. If unsure, say N here.
  920. config VM86
  921. bool
  922. default X86_LEGACY_VM86
  923. config X86_16BIT
  924. bool "Enable support for 16-bit segments" if EXPERT
  925. default y
  926. depends on MODIFY_LDT_SYSCALL
  927. ---help---
  928. This option is required by programs like Wine to run 16-bit
  929. protected mode legacy code on x86 processors. Disabling
  930. this option saves about 300 bytes on i386, or around 6K text
  931. plus 16K runtime memory on x86-64,
  932. config X86_ESPFIX32
  933. def_bool y
  934. depends on X86_16BIT && X86_32
  935. config X86_ESPFIX64
  936. def_bool y
  937. depends on X86_16BIT && X86_64
  938. config X86_VSYSCALL_EMULATION
  939. bool "Enable vsyscall emulation" if EXPERT
  940. default y
  941. depends on X86_64
  942. ---help---
  943. This enables emulation of the legacy vsyscall page. Disabling
  944. it is roughly equivalent to booting with vsyscall=none, except
  945. that it will also disable the helpful warning if a program
  946. tries to use a vsyscall. With this option set to N, offending
  947. programs will just segfault, citing addresses of the form
  948. 0xffffffffff600?00.
  949. This option is required by many programs built before 2013, and
  950. care should be used even with newer programs if set to N.
  951. Disabling this option saves about 7K of kernel size and
  952. possibly 4K of additional runtime pagetable memory.
  953. config TOSHIBA
  954. tristate "Toshiba Laptop support"
  955. depends on X86_32
  956. ---help---
  957. This adds a driver to safely access the System Management Mode of
  958. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  959. not work on models with a Phoenix BIOS. The System Management Mode
  960. is used to set the BIOS and power saving options on Toshiba portables.
  961. For information on utilities to make use of this driver see the
  962. Toshiba Linux utilities web site at:
  963. <http://www.buzzard.org.uk/toshiba/>.
  964. Say Y if you intend to run this kernel on a Toshiba portable.
  965. Say N otherwise.
  966. config I8K
  967. tristate "Dell i8k legacy laptop support"
  968. select HWMON
  969. select SENSORS_DELL_SMM
  970. ---help---
  971. This option enables legacy /proc/i8k userspace interface in hwmon
  972. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  973. temperature and allows controlling fan speeds of Dell laptops via
  974. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  975. it reports also power and hotkey status. For fan speed control is
  976. needed userspace package i8kutils.
  977. Say Y if you intend to run this kernel on old Dell laptops or want to
  978. use userspace package i8kutils.
  979. Say N otherwise.
  980. config X86_REBOOTFIXUPS
  981. bool "Enable X86 board specific fixups for reboot"
  982. depends on X86_32
  983. ---help---
  984. This enables chipset and/or board specific fixups to be done
  985. in order to get reboot to work correctly. This is only needed on
  986. some combinations of hardware and BIOS. The symptom, for which
  987. this config is intended, is when reboot ends with a stalled/hung
  988. system.
  989. Currently, the only fixup is for the Geode machines using
  990. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  991. Say Y if you want to enable the fixup. Currently, it's safe to
  992. enable this option even if you don't need it.
  993. Say N otherwise.
  994. config MICROCODE
  995. bool "CPU microcode loading support"
  996. default y
  997. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  998. select FW_LOADER
  999. ---help---
  1000. If you say Y here, you will be able to update the microcode on
  1001. Intel and AMD processors. The Intel support is for the IA32 family,
  1002. e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
  1003. AMD support is for families 0x10 and later. You will obviously need
  1004. the actual microcode binary data itself which is not shipped with
  1005. the Linux kernel.
  1006. The preferred method to load microcode from a detached initrd is described
  1007. in Documentation/x86/early-microcode.txt. For that you need to enable
  1008. CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
  1009. initrd for microcode blobs.
  1010. In addition, you can build-in the microcode into the kernel. For that you
  1011. need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
  1012. to the CONFIG_EXTRA_FIRMWARE config option.
  1013. config MICROCODE_INTEL
  1014. bool "Intel microcode loading support"
  1015. depends on MICROCODE
  1016. default MICROCODE
  1017. select FW_LOADER
  1018. ---help---
  1019. This options enables microcode patch loading support for Intel
  1020. processors.
  1021. For the current Intel microcode data package go to
  1022. <https://downloadcenter.intel.com> and search for
  1023. 'Linux Processor Microcode Data File'.
  1024. config MICROCODE_AMD
  1025. bool "AMD microcode loading support"
  1026. depends on MICROCODE
  1027. select FW_LOADER
  1028. ---help---
  1029. If you select this option, microcode patch loading support for AMD
  1030. processors will be enabled.
  1031. config MICROCODE_OLD_INTERFACE
  1032. def_bool y
  1033. depends on MICROCODE
  1034. config X86_MSR
  1035. tristate "/dev/cpu/*/msr - Model-specific register support"
  1036. ---help---
  1037. This device gives privileged processes access to the x86
  1038. Model-Specific Registers (MSRs). It is a character device with
  1039. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1040. MSR accesses are directed to a specific CPU on multi-processor
  1041. systems.
  1042. config X86_CPUID
  1043. tristate "/dev/cpu/*/cpuid - CPU information support"
  1044. ---help---
  1045. This device gives processes access to the x86 CPUID instruction to
  1046. be executed on a specific processor. It is a character device
  1047. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1048. /dev/cpu/31/cpuid.
  1049. choice
  1050. prompt "High Memory Support"
  1051. default HIGHMEM4G
  1052. depends on X86_32
  1053. config NOHIGHMEM
  1054. bool "off"
  1055. ---help---
  1056. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1057. However, the address space of 32-bit x86 processors is only 4
  1058. Gigabytes large. That means that, if you have a large amount of
  1059. physical memory, not all of it can be "permanently mapped" by the
  1060. kernel. The physical memory that's not permanently mapped is called
  1061. "high memory".
  1062. If you are compiling a kernel which will never run on a machine with
  1063. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1064. choice and suitable for most users). This will result in a "3GB/1GB"
  1065. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1066. space and the remaining part of the 4GB virtual memory space is used
  1067. by the kernel to permanently map as much physical memory as
  1068. possible.
  1069. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1070. answer "4GB" here.
  1071. If more than 4 Gigabytes is used then answer "64GB" here. This
  1072. selection turns Intel PAE (Physical Address Extension) mode on.
  1073. PAE implements 3-level paging on IA32 processors. PAE is fully
  1074. supported by Linux, PAE mode is implemented on all recent Intel
  1075. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1076. then the kernel will not boot on CPUs that don't support PAE!
  1077. The actual amount of total physical memory will either be
  1078. auto detected or can be forced by using a kernel command line option
  1079. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1080. your boot loader (lilo or loadlin) about how to pass options to the
  1081. kernel at boot time.)
  1082. If unsure, say "off".
  1083. config HIGHMEM4G
  1084. bool "4GB"
  1085. ---help---
  1086. Select this if you have a 32-bit processor and between 1 and 4
  1087. gigabytes of physical RAM.
  1088. config HIGHMEM64G
  1089. bool "64GB"
  1090. depends on !M486
  1091. select X86_PAE
  1092. ---help---
  1093. Select this if you have a 32-bit processor and more than 4
  1094. gigabytes of physical RAM.
  1095. endchoice
  1096. choice
  1097. prompt "Memory split" if EXPERT
  1098. default VMSPLIT_3G
  1099. depends on X86_32
  1100. ---help---
  1101. Select the desired split between kernel and user memory.
  1102. If the address range available to the kernel is less than the
  1103. physical memory installed, the remaining memory will be available
  1104. as "high memory". Accessing high memory is a little more costly
  1105. than low memory, as it needs to be mapped into the kernel first.
  1106. Note that increasing the kernel address space limits the range
  1107. available to user programs, making the address space there
  1108. tighter. Selecting anything other than the default 3G/1G split
  1109. will also likely make your kernel incompatible with binary-only
  1110. kernel modules.
  1111. If you are not absolutely sure what you are doing, leave this
  1112. option alone!
  1113. config VMSPLIT_3G
  1114. bool "3G/1G user/kernel split"
  1115. config VMSPLIT_3G_OPT
  1116. depends on !X86_PAE
  1117. bool "3G/1G user/kernel split (for full 1G low memory)"
  1118. config VMSPLIT_2G
  1119. bool "2G/2G user/kernel split"
  1120. config VMSPLIT_2G_OPT
  1121. depends on !X86_PAE
  1122. bool "2G/2G user/kernel split (for full 2G low memory)"
  1123. config VMSPLIT_1G
  1124. bool "1G/3G user/kernel split"
  1125. endchoice
  1126. config PAGE_OFFSET
  1127. hex
  1128. default 0xB0000000 if VMSPLIT_3G_OPT
  1129. default 0x80000000 if VMSPLIT_2G
  1130. default 0x78000000 if VMSPLIT_2G_OPT
  1131. default 0x40000000 if VMSPLIT_1G
  1132. default 0xC0000000
  1133. depends on X86_32
  1134. config HIGHMEM
  1135. def_bool y
  1136. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1137. config X86_PAE
  1138. bool "PAE (Physical Address Extension) Support"
  1139. depends on X86_32 && !HIGHMEM4G
  1140. select SWIOTLB
  1141. ---help---
  1142. PAE is required for NX support, and furthermore enables
  1143. larger swapspace support for non-overcommit purposes. It
  1144. has the cost of more pagetable lookup overhead, and also
  1145. consumes more pagetable space per process.
  1146. config ARCH_PHYS_ADDR_T_64BIT
  1147. def_bool y
  1148. depends on X86_64 || X86_PAE
  1149. config ARCH_DMA_ADDR_T_64BIT
  1150. def_bool y
  1151. depends on X86_64 || HIGHMEM64G
  1152. config X86_DIRECT_GBPAGES
  1153. def_bool y
  1154. depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
  1155. ---help---
  1156. Certain kernel features effectively disable kernel
  1157. linear 1 GB mappings (even if the CPU otherwise
  1158. supports them), so don't confuse the user by printing
  1159. that we have them enabled.
  1160. # Common NUMA Features
  1161. config NUMA
  1162. bool "Numa Memory Allocation and Scheduler Support"
  1163. depends on SMP
  1164. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1165. default y if X86_BIGSMP
  1166. ---help---
  1167. Enable NUMA (Non Uniform Memory Access) support.
  1168. The kernel will try to allocate memory used by a CPU on the
  1169. local memory controller of the CPU and add some more
  1170. NUMA awareness to the kernel.
  1171. For 64-bit this is recommended if the system is Intel Core i7
  1172. (or later), AMD Opteron, or EM64T NUMA.
  1173. For 32-bit this is only needed if you boot a 32-bit
  1174. kernel on a 64-bit NUMA platform.
  1175. Otherwise, you should say N.
  1176. config AMD_NUMA
  1177. def_bool y
  1178. prompt "Old style AMD Opteron NUMA detection"
  1179. depends on X86_64 && NUMA && PCI
  1180. ---help---
  1181. Enable AMD NUMA node topology detection. You should say Y here if
  1182. you have a multi processor AMD system. This uses an old method to
  1183. read the NUMA configuration directly from the builtin Northbridge
  1184. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1185. which also takes priority if both are compiled in.
  1186. config X86_64_ACPI_NUMA
  1187. def_bool y
  1188. prompt "ACPI NUMA detection"
  1189. depends on X86_64 && NUMA && ACPI && PCI
  1190. select ACPI_NUMA
  1191. ---help---
  1192. Enable ACPI SRAT based node topology detection.
  1193. # Some NUMA nodes have memory ranges that span
  1194. # other nodes. Even though a pfn is valid and
  1195. # between a node's start and end pfns, it may not
  1196. # reside on that node. See memmap_init_zone()
  1197. # for details.
  1198. config NODES_SPAN_OTHER_NODES
  1199. def_bool y
  1200. depends on X86_64_ACPI_NUMA
  1201. config NUMA_EMU
  1202. bool "NUMA emulation"
  1203. depends on NUMA
  1204. ---help---
  1205. Enable NUMA emulation. A flat machine will be split
  1206. into virtual nodes when booted with "numa=fake=N", where N is the
  1207. number of nodes. This is only useful for debugging.
  1208. config NODES_SHIFT
  1209. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1210. range 1 10
  1211. default "10" if MAXSMP
  1212. default "6" if X86_64
  1213. default "3"
  1214. depends on NEED_MULTIPLE_NODES
  1215. ---help---
  1216. Specify the maximum number of NUMA Nodes available on the target
  1217. system. Increases memory reserved to accommodate various tables.
  1218. config ARCH_HAVE_MEMORY_PRESENT
  1219. def_bool y
  1220. depends on X86_32 && DISCONTIGMEM
  1221. config NEED_NODE_MEMMAP_SIZE
  1222. def_bool y
  1223. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1224. config ARCH_FLATMEM_ENABLE
  1225. def_bool y
  1226. depends on X86_32 && !NUMA
  1227. config ARCH_DISCONTIGMEM_ENABLE
  1228. def_bool y
  1229. depends on NUMA && X86_32
  1230. config ARCH_DISCONTIGMEM_DEFAULT
  1231. def_bool y
  1232. depends on NUMA && X86_32
  1233. config ARCH_SPARSEMEM_ENABLE
  1234. def_bool y
  1235. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1236. select SPARSEMEM_STATIC if X86_32
  1237. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1238. config ARCH_SPARSEMEM_DEFAULT
  1239. def_bool y
  1240. depends on X86_64
  1241. config ARCH_SELECT_MEMORY_MODEL
  1242. def_bool y
  1243. depends on ARCH_SPARSEMEM_ENABLE
  1244. config ARCH_MEMORY_PROBE
  1245. bool "Enable sysfs memory/probe interface"
  1246. depends on X86_64 && MEMORY_HOTPLUG
  1247. help
  1248. This option enables a sysfs memory/probe interface for testing.
  1249. See Documentation/memory-hotplug.txt for more information.
  1250. If you are unsure how to answer this question, answer N.
  1251. config ARCH_PROC_KCORE_TEXT
  1252. def_bool y
  1253. depends on X86_64 && PROC_KCORE
  1254. config ILLEGAL_POINTER_VALUE
  1255. hex
  1256. default 0 if X86_32
  1257. default 0xdead000000000000 if X86_64
  1258. source "mm/Kconfig"
  1259. config X86_PMEM_LEGACY_DEVICE
  1260. bool
  1261. config X86_PMEM_LEGACY
  1262. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1263. depends on PHYS_ADDR_T_64BIT
  1264. depends on BLK_DEV
  1265. select X86_PMEM_LEGACY_DEVICE
  1266. select LIBNVDIMM
  1267. help
  1268. Treat memory marked using the non-standard e820 type of 12 as used
  1269. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1270. The kernel will offer these regions to the 'pmem' driver so
  1271. they can be used for persistent storage.
  1272. Say Y if unsure.
  1273. config HIGHPTE
  1274. bool "Allocate 3rd-level pagetables from highmem"
  1275. depends on HIGHMEM
  1276. ---help---
  1277. The VM uses one page table entry for each page of physical memory.
  1278. For systems with a lot of RAM, this can be wasteful of precious
  1279. low memory. Setting this option will put user-space page table
  1280. entries in high memory.
  1281. config X86_CHECK_BIOS_CORRUPTION
  1282. bool "Check for low memory corruption"
  1283. ---help---
  1284. Periodically check for memory corruption in low memory, which
  1285. is suspected to be caused by BIOS. Even when enabled in the
  1286. configuration, it is disabled at runtime. Enable it by
  1287. setting "memory_corruption_check=1" on the kernel command
  1288. line. By default it scans the low 64k of memory every 60
  1289. seconds; see the memory_corruption_check_size and
  1290. memory_corruption_check_period parameters in
  1291. Documentation/kernel-parameters.txt to adjust this.
  1292. When enabled with the default parameters, this option has
  1293. almost no overhead, as it reserves a relatively small amount
  1294. of memory and scans it infrequently. It both detects corruption
  1295. and prevents it from affecting the running system.
  1296. It is, however, intended as a diagnostic tool; if repeatable
  1297. BIOS-originated corruption always affects the same memory,
  1298. you can use memmap= to prevent the kernel from using that
  1299. memory.
  1300. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1301. bool "Set the default setting of memory_corruption_check"
  1302. depends on X86_CHECK_BIOS_CORRUPTION
  1303. default y
  1304. ---help---
  1305. Set whether the default state of memory_corruption_check is
  1306. on or off.
  1307. config X86_RESERVE_LOW
  1308. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1309. default 64
  1310. range 4 640
  1311. ---help---
  1312. Specify the amount of low memory to reserve for the BIOS.
  1313. The first page contains BIOS data structures that the kernel
  1314. must not use, so that page must always be reserved.
  1315. By default we reserve the first 64K of physical RAM, as a
  1316. number of BIOSes are known to corrupt that memory range
  1317. during events such as suspend/resume or monitor cable
  1318. insertion, so it must not be used by the kernel.
  1319. You can set this to 4 if you are absolutely sure that you
  1320. trust the BIOS to get all its memory reservations and usages
  1321. right. If you know your BIOS have problems beyond the
  1322. default 64K area, you can set this to 640 to avoid using the
  1323. entire low memory range.
  1324. If you have doubts about the BIOS (e.g. suspend/resume does
  1325. not work or there's kernel crashes after certain hardware
  1326. hotplug events) then you might want to enable
  1327. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1328. typical corruption patterns.
  1329. Leave this to the default value of 64 if you are unsure.
  1330. config MATH_EMULATION
  1331. bool
  1332. depends on MODIFY_LDT_SYSCALL
  1333. prompt "Math emulation" if X86_32
  1334. ---help---
  1335. Linux can emulate a math coprocessor (used for floating point
  1336. operations) if you don't have one. 486DX and Pentium processors have
  1337. a math coprocessor built in, 486SX and 386 do not, unless you added
  1338. a 487DX or 387, respectively. (The messages during boot time can
  1339. give you some hints here ["man dmesg"].) Everyone needs either a
  1340. coprocessor or this emulation.
  1341. If you don't have a math coprocessor, you need to say Y here; if you
  1342. say Y here even though you have a coprocessor, the coprocessor will
  1343. be used nevertheless. (This behavior can be changed with the kernel
  1344. command line option "no387", which comes handy if your coprocessor
  1345. is broken. Try "man bootparam" or see the documentation of your boot
  1346. loader (lilo or loadlin) about how to pass options to the kernel at
  1347. boot time.) This means that it is a good idea to say Y here if you
  1348. intend to use this kernel on different machines.
  1349. More information about the internals of the Linux math coprocessor
  1350. emulation can be found in <file:arch/x86/math-emu/README>.
  1351. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1352. kernel, it won't hurt.
  1353. config MTRR
  1354. def_bool y
  1355. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1356. ---help---
  1357. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1358. the Memory Type Range Registers (MTRRs) may be used to control
  1359. processor access to memory ranges. This is most useful if you have
  1360. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1361. allows bus write transfers to be combined into a larger transfer
  1362. before bursting over the PCI/AGP bus. This can increase performance
  1363. of image write operations 2.5 times or more. Saying Y here creates a
  1364. /proc/mtrr file which may be used to manipulate your processor's
  1365. MTRRs. Typically the X server should use this.
  1366. This code has a reasonably generic interface so that similar
  1367. control registers on other processors can be easily supported
  1368. as well:
  1369. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1370. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1371. these, the ARRs are used to emulate the MTRRs.
  1372. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1373. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1374. write-combining. All of these processors are supported by this code
  1375. and it makes sense to say Y here if you have one of them.
  1376. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1377. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1378. can lead to all sorts of problems, so it's good to say Y here.
  1379. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1380. just add about 9 KB to your kernel.
  1381. See <file:Documentation/x86/mtrr.txt> for more information.
  1382. config MTRR_SANITIZER
  1383. def_bool y
  1384. prompt "MTRR cleanup support"
  1385. depends on MTRR
  1386. ---help---
  1387. Convert MTRR layout from continuous to discrete, so X drivers can
  1388. add writeback entries.
  1389. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1390. The largest mtrr entry size for a continuous block can be set with
  1391. mtrr_chunk_size.
  1392. If unsure, say Y.
  1393. config MTRR_SANITIZER_ENABLE_DEFAULT
  1394. int "MTRR cleanup enable value (0-1)"
  1395. range 0 1
  1396. default "0"
  1397. depends on MTRR_SANITIZER
  1398. ---help---
  1399. Enable mtrr cleanup default value
  1400. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1401. int "MTRR cleanup spare reg num (0-7)"
  1402. range 0 7
  1403. default "1"
  1404. depends on MTRR_SANITIZER
  1405. ---help---
  1406. mtrr cleanup spare entries default, it can be changed via
  1407. mtrr_spare_reg_nr=N on the kernel command line.
  1408. config X86_PAT
  1409. def_bool y
  1410. prompt "x86 PAT support" if EXPERT
  1411. depends on MTRR
  1412. ---help---
  1413. Use PAT attributes to setup page level cache control.
  1414. PATs are the modern equivalents of MTRRs and are much more
  1415. flexible than MTRRs.
  1416. Say N here if you see bootup problems (boot crash, boot hang,
  1417. spontaneous reboots) or a non-working video driver.
  1418. If unsure, say Y.
  1419. config ARCH_USES_PG_UNCACHED
  1420. def_bool y
  1421. depends on X86_PAT
  1422. config ARCH_RANDOM
  1423. def_bool y
  1424. prompt "x86 architectural random number generator" if EXPERT
  1425. ---help---
  1426. Enable the x86 architectural RDRAND instruction
  1427. (Intel Bull Mountain technology) to generate random numbers.
  1428. If supported, this is a high bandwidth, cryptographically
  1429. secure hardware random number generator.
  1430. config X86_SMAP
  1431. def_bool y
  1432. prompt "Supervisor Mode Access Prevention" if EXPERT
  1433. ---help---
  1434. Supervisor Mode Access Prevention (SMAP) is a security
  1435. feature in newer Intel processors. There is a small
  1436. performance cost if this enabled and turned on; there is
  1437. also a small increase in the kernel size if this is enabled.
  1438. If unsure, say Y.
  1439. config X86_INTEL_MPX
  1440. prompt "Intel MPX (Memory Protection Extensions)"
  1441. def_bool n
  1442. depends on CPU_SUP_INTEL
  1443. ---help---
  1444. MPX provides hardware features that can be used in
  1445. conjunction with compiler-instrumented code to check
  1446. memory references. It is designed to detect buffer
  1447. overflow or underflow bugs.
  1448. This option enables running applications which are
  1449. instrumented or otherwise use MPX. It does not use MPX
  1450. itself inside the kernel or to protect the kernel
  1451. against bad memory references.
  1452. Enabling this option will make the kernel larger:
  1453. ~8k of kernel text and 36 bytes of data on a 64-bit
  1454. defconfig. It adds a long to the 'mm_struct' which
  1455. will increase the kernel memory overhead of each
  1456. process and adds some branches to paths used during
  1457. exec() and munmap().
  1458. For details, see Documentation/x86/intel_mpx.txt
  1459. If unsure, say N.
  1460. config X86_INTEL_MEMORY_PROTECTION_KEYS
  1461. prompt "Intel Memory Protection Keys"
  1462. def_bool y
  1463. # Note: only available in 64-bit mode
  1464. depends on CPU_SUP_INTEL && X86_64
  1465. ---help---
  1466. Memory Protection Keys provides a mechanism for enforcing
  1467. page-based protections, but without requiring modification of the
  1468. page tables when an application changes protection domains.
  1469. For details, see Documentation/x86/protection-keys.txt
  1470. If unsure, say y.
  1471. config EFI
  1472. bool "EFI runtime service support"
  1473. depends on ACPI
  1474. select UCS2_STRING
  1475. select EFI_RUNTIME_WRAPPERS
  1476. ---help---
  1477. This enables the kernel to use EFI runtime services that are
  1478. available (such as the EFI variable services).
  1479. This option is only useful on systems that have EFI firmware.
  1480. In addition, you should use the latest ELILO loader available
  1481. at <http://elilo.sourceforge.net> in order to take advantage
  1482. of EFI runtime services. However, even with this option, the
  1483. resultant kernel should continue to boot on existing non-EFI
  1484. platforms.
  1485. config EFI_STUB
  1486. bool "EFI stub support"
  1487. depends on EFI && !X86_USE_3DNOW
  1488. select RELOCATABLE
  1489. ---help---
  1490. This kernel feature allows a bzImage to be loaded directly
  1491. by EFI firmware without the use of a bootloader.
  1492. See Documentation/efi-stub.txt for more information.
  1493. config EFI_MIXED
  1494. bool "EFI mixed-mode support"
  1495. depends on EFI_STUB && X86_64
  1496. ---help---
  1497. Enabling this feature allows a 64-bit kernel to be booted
  1498. on a 32-bit firmware, provided that your CPU supports 64-bit
  1499. mode.
  1500. Note that it is not possible to boot a mixed-mode enabled
  1501. kernel via the EFI boot stub - a bootloader that supports
  1502. the EFI handover protocol must be used.
  1503. If unsure, say N.
  1504. config SECCOMP
  1505. def_bool y
  1506. prompt "Enable seccomp to safely compute untrusted bytecode"
  1507. ---help---
  1508. This kernel feature is useful for number crunching applications
  1509. that may need to compute untrusted bytecode during their
  1510. execution. By using pipes or other transports made available to
  1511. the process as file descriptors supporting the read/write
  1512. syscalls, it's possible to isolate those applications in
  1513. their own address space using seccomp. Once seccomp is
  1514. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1515. and the task is only allowed to execute a few safe syscalls
  1516. defined by each seccomp mode.
  1517. If unsure, say Y. Only embedded should say N here.
  1518. source kernel/Kconfig.hz
  1519. config KEXEC
  1520. bool "kexec system call"
  1521. select KEXEC_CORE
  1522. ---help---
  1523. kexec is a system call that implements the ability to shutdown your
  1524. current kernel, and to start another kernel. It is like a reboot
  1525. but it is independent of the system firmware. And like a reboot
  1526. you can start any kernel with it, not just Linux.
  1527. The name comes from the similarity to the exec system call.
  1528. It is an ongoing process to be certain the hardware in a machine
  1529. is properly shutdown, so do not be surprised if this code does not
  1530. initially work for you. As of this writing the exact hardware
  1531. interface is strongly in flux, so no good recommendation can be
  1532. made.
  1533. config KEXEC_FILE
  1534. bool "kexec file based system call"
  1535. select KEXEC_CORE
  1536. select BUILD_BIN2C
  1537. depends on X86_64
  1538. depends on CRYPTO=y
  1539. depends on CRYPTO_SHA256=y
  1540. ---help---
  1541. This is new version of kexec system call. This system call is
  1542. file based and takes file descriptors as system call argument
  1543. for kernel and initramfs as opposed to list of segments as
  1544. accepted by previous system call.
  1545. config KEXEC_VERIFY_SIG
  1546. bool "Verify kernel signature during kexec_file_load() syscall"
  1547. depends on KEXEC_FILE
  1548. ---help---
  1549. This option makes kernel signature verification mandatory for
  1550. the kexec_file_load() syscall.
  1551. In addition to that option, you need to enable signature
  1552. verification for the corresponding kernel image type being
  1553. loaded in order for this to work.
  1554. config KEXEC_BZIMAGE_VERIFY_SIG
  1555. bool "Enable bzImage signature verification support"
  1556. depends on KEXEC_VERIFY_SIG
  1557. depends on SIGNED_PE_FILE_VERIFICATION
  1558. select SYSTEM_TRUSTED_KEYRING
  1559. ---help---
  1560. Enable bzImage signature verification support.
  1561. config CRASH_DUMP
  1562. bool "kernel crash dumps"
  1563. depends on X86_64 || (X86_32 && HIGHMEM)
  1564. ---help---
  1565. Generate crash dump after being started by kexec.
  1566. This should be normally only set in special crash dump kernels
  1567. which are loaded in the main kernel with kexec-tools into
  1568. a specially reserved region and then later executed after
  1569. a crash by kdump/kexec. The crash dump kernel must be compiled
  1570. to a memory address not used by the main kernel or BIOS using
  1571. PHYSICAL_START, or it must be built as a relocatable image
  1572. (CONFIG_RELOCATABLE=y).
  1573. For more details see Documentation/kdump/kdump.txt
  1574. config KEXEC_JUMP
  1575. bool "kexec jump"
  1576. depends on KEXEC && HIBERNATION
  1577. ---help---
  1578. Jump between original kernel and kexeced kernel and invoke
  1579. code in physical address mode via KEXEC
  1580. config PHYSICAL_START
  1581. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1582. default "0x1000000"
  1583. ---help---
  1584. This gives the physical address where the kernel is loaded.
  1585. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1586. bzImage will decompress itself to above physical address and
  1587. run from there. Otherwise, bzImage will run from the address where
  1588. it has been loaded by the boot loader and will ignore above physical
  1589. address.
  1590. In normal kdump cases one does not have to set/change this option
  1591. as now bzImage can be compiled as a completely relocatable image
  1592. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1593. address. This option is mainly useful for the folks who don't want
  1594. to use a bzImage for capturing the crash dump and want to use a
  1595. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1596. to be specifically compiled to run from a specific memory area
  1597. (normally a reserved region) and this option comes handy.
  1598. So if you are using bzImage for capturing the crash dump,
  1599. leave the value here unchanged to 0x1000000 and set
  1600. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1601. for capturing the crash dump change this value to start of
  1602. the reserved region. In other words, it can be set based on
  1603. the "X" value as specified in the "crashkernel=YM@XM"
  1604. command line boot parameter passed to the panic-ed
  1605. kernel. Please take a look at Documentation/kdump/kdump.txt
  1606. for more details about crash dumps.
  1607. Usage of bzImage for capturing the crash dump is recommended as
  1608. one does not have to build two kernels. Same kernel can be used
  1609. as production kernel and capture kernel. Above option should have
  1610. gone away after relocatable bzImage support is introduced. But it
  1611. is present because there are users out there who continue to use
  1612. vmlinux for dump capture. This option should go away down the
  1613. line.
  1614. Don't change this unless you know what you are doing.
  1615. config RELOCATABLE
  1616. bool "Build a relocatable kernel"
  1617. default y
  1618. ---help---
  1619. This builds a kernel image that retains relocation information
  1620. so it can be loaded someplace besides the default 1MB.
  1621. The relocations tend to make the kernel binary about 10% larger,
  1622. but are discarded at runtime.
  1623. One use is for the kexec on panic case where the recovery kernel
  1624. must live at a different physical address than the primary
  1625. kernel.
  1626. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1627. it has been loaded at and the compile time physical address
  1628. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1629. config RANDOMIZE_BASE
  1630. bool "Randomize the address of the kernel image (KASLR)"
  1631. depends on RELOCATABLE
  1632. default n
  1633. ---help---
  1634. In support of Kernel Address Space Layout Randomization (KASLR),
  1635. this randomizes the physical address at which the kernel image
  1636. is decompressed and the virtual address where the kernel
  1637. image is mapped, as a security feature that deters exploit
  1638. attempts relying on knowledge of the location of kernel
  1639. code internals.
  1640. The kernel physical and virtual address can be randomized
  1641. from 16MB up to 1GB on 64-bit and 512MB on 32-bit. (Note that
  1642. using RANDOMIZE_BASE reduces the memory space available to
  1643. kernel modules from 1.5GB to 1GB.)
  1644. Entropy is generated using the RDRAND instruction if it is
  1645. supported. If RDTSC is supported, its value is mixed into
  1646. the entropy pool as well. If neither RDRAND nor RDTSC are
  1647. supported, then entropy is read from the i8254 timer.
  1648. Since the kernel is built using 2GB addressing, and
  1649. PHYSICAL_ALIGN must be at a minimum of 2MB, only 10 bits of
  1650. entropy is theoretically possible. Currently, with the
  1651. default value for PHYSICAL_ALIGN and due to page table
  1652. layouts, 64-bit uses 9 bits of entropy and 32-bit uses 8 bits.
  1653. If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot
  1654. time. To enable it, boot with "kaslr" on the kernel command
  1655. line (which will also disable hibernation).
  1656. If unsure, say N.
  1657. # Relocation on x86 needs some additional build support
  1658. config X86_NEED_RELOCS
  1659. def_bool y
  1660. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1661. config PHYSICAL_ALIGN
  1662. hex "Alignment value to which kernel should be aligned"
  1663. default "0x200000"
  1664. range 0x2000 0x1000000 if X86_32
  1665. range 0x200000 0x1000000 if X86_64
  1666. ---help---
  1667. This value puts the alignment restrictions on physical address
  1668. where kernel is loaded and run from. Kernel is compiled for an
  1669. address which meets above alignment restriction.
  1670. If bootloader loads the kernel at a non-aligned address and
  1671. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1672. address aligned to above value and run from there.
  1673. If bootloader loads the kernel at a non-aligned address and
  1674. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1675. load address and decompress itself to the address it has been
  1676. compiled for and run from there. The address for which kernel is
  1677. compiled already meets above alignment restrictions. Hence the
  1678. end result is that kernel runs from a physical address meeting
  1679. above alignment restrictions.
  1680. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1681. this value must be a multiple of 0x200000.
  1682. Don't change this unless you know what you are doing.
  1683. config HOTPLUG_CPU
  1684. bool "Support for hot-pluggable CPUs"
  1685. depends on SMP
  1686. ---help---
  1687. Say Y here to allow turning CPUs off and on. CPUs can be
  1688. controlled through /sys/devices/system/cpu.
  1689. ( Note: power management support will enable this option
  1690. automatically on SMP systems. )
  1691. Say N if you want to disable CPU hotplug.
  1692. config BOOTPARAM_HOTPLUG_CPU0
  1693. bool "Set default setting of cpu0_hotpluggable"
  1694. default n
  1695. depends on HOTPLUG_CPU
  1696. ---help---
  1697. Set whether default state of cpu0_hotpluggable is on or off.
  1698. Say Y here to enable CPU0 hotplug by default. If this switch
  1699. is turned on, there is no need to give cpu0_hotplug kernel
  1700. parameter and the CPU0 hotplug feature is enabled by default.
  1701. Please note: there are two known CPU0 dependencies if you want
  1702. to enable the CPU0 hotplug feature either by this switch or by
  1703. cpu0_hotplug kernel parameter.
  1704. First, resume from hibernate or suspend always starts from CPU0.
  1705. So hibernate and suspend are prevented if CPU0 is offline.
  1706. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1707. offline if any interrupt can not migrate out of CPU0. There may
  1708. be other CPU0 dependencies.
  1709. Please make sure the dependencies are under your control before
  1710. you enable this feature.
  1711. Say N if you don't want to enable CPU0 hotplug feature by default.
  1712. You still can enable the CPU0 hotplug feature at boot by kernel
  1713. parameter cpu0_hotplug.
  1714. config DEBUG_HOTPLUG_CPU0
  1715. def_bool n
  1716. prompt "Debug CPU0 hotplug"
  1717. depends on HOTPLUG_CPU
  1718. ---help---
  1719. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1720. soon as possible and boots up userspace with CPU0 offlined. User
  1721. can online CPU0 back after boot time.
  1722. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1723. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1724. compilation or giving cpu0_hotplug kernel parameter at boot.
  1725. If unsure, say N.
  1726. config COMPAT_VDSO
  1727. def_bool n
  1728. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1729. depends on X86_32 || IA32_EMULATION
  1730. ---help---
  1731. Certain buggy versions of glibc will crash if they are
  1732. presented with a 32-bit vDSO that is not mapped at the address
  1733. indicated in its segment table.
  1734. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1735. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1736. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1737. the only released version with the bug, but OpenSUSE 9
  1738. contains a buggy "glibc 2.3.2".
  1739. The symptom of the bug is that everything crashes on startup, saying:
  1740. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1741. Saying Y here changes the default value of the vdso32 boot
  1742. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1743. This works around the glibc bug but hurts performance.
  1744. If unsure, say N: if you are compiling your own kernel, you
  1745. are unlikely to be using a buggy version of glibc.
  1746. choice
  1747. prompt "vsyscall table for legacy applications"
  1748. depends on X86_64
  1749. default LEGACY_VSYSCALL_EMULATE
  1750. help
  1751. Legacy user code that does not know how to find the vDSO expects
  1752. to be able to issue three syscalls by calling fixed addresses in
  1753. kernel space. Since this location is not randomized with ASLR,
  1754. it can be used to assist security vulnerability exploitation.
  1755. This setting can be changed at boot time via the kernel command
  1756. line parameter vsyscall=[native|emulate|none].
  1757. On a system with recent enough glibc (2.14 or newer) and no
  1758. static binaries, you can say None without a performance penalty
  1759. to improve security.
  1760. If unsure, select "Emulate".
  1761. config LEGACY_VSYSCALL_NATIVE
  1762. bool "Native"
  1763. help
  1764. Actual executable code is located in the fixed vsyscall
  1765. address mapping, implementing time() efficiently. Since
  1766. this makes the mapping executable, it can be used during
  1767. security vulnerability exploitation (traditionally as
  1768. ROP gadgets). This configuration is not recommended.
  1769. config LEGACY_VSYSCALL_EMULATE
  1770. bool "Emulate"
  1771. help
  1772. The kernel traps and emulates calls into the fixed
  1773. vsyscall address mapping. This makes the mapping
  1774. non-executable, but it still contains known contents,
  1775. which could be used in certain rare security vulnerability
  1776. exploits. This configuration is recommended when userspace
  1777. still uses the vsyscall area.
  1778. config LEGACY_VSYSCALL_NONE
  1779. bool "None"
  1780. help
  1781. There will be no vsyscall mapping at all. This will
  1782. eliminate any risk of ASLR bypass due to the vsyscall
  1783. fixed address mapping. Attempts to use the vsyscalls
  1784. will be reported to dmesg, so that either old or
  1785. malicious userspace programs can be identified.
  1786. endchoice
  1787. config CMDLINE_BOOL
  1788. bool "Built-in kernel command line"
  1789. ---help---
  1790. Allow for specifying boot arguments to the kernel at
  1791. build time. On some systems (e.g. embedded ones), it is
  1792. necessary or convenient to provide some or all of the
  1793. kernel boot arguments with the kernel itself (that is,
  1794. to not rely on the boot loader to provide them.)
  1795. To compile command line arguments into the kernel,
  1796. set this option to 'Y', then fill in the
  1797. boot arguments in CONFIG_CMDLINE.
  1798. Systems with fully functional boot loaders (i.e. non-embedded)
  1799. should leave this option set to 'N'.
  1800. config CMDLINE
  1801. string "Built-in kernel command string"
  1802. depends on CMDLINE_BOOL
  1803. default ""
  1804. ---help---
  1805. Enter arguments here that should be compiled into the kernel
  1806. image and used at boot time. If the boot loader provides a
  1807. command line at boot time, it is appended to this string to
  1808. form the full kernel command line, when the system boots.
  1809. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1810. change this behavior.
  1811. In most cases, the command line (whether built-in or provided
  1812. by the boot loader) should specify the device for the root
  1813. file system.
  1814. config CMDLINE_OVERRIDE
  1815. bool "Built-in command line overrides boot loader arguments"
  1816. depends on CMDLINE_BOOL
  1817. ---help---
  1818. Set this option to 'Y' to have the kernel ignore the boot loader
  1819. command line, and use ONLY the built-in command line.
  1820. This is used to work around broken boot loaders. This should
  1821. be set to 'N' under normal conditions.
  1822. config MODIFY_LDT_SYSCALL
  1823. bool "Enable the LDT (local descriptor table)" if EXPERT
  1824. default y
  1825. ---help---
  1826. Linux can allow user programs to install a per-process x86
  1827. Local Descriptor Table (LDT) using the modify_ldt(2) system
  1828. call. This is required to run 16-bit or segmented code such as
  1829. DOSEMU or some Wine programs. It is also used by some very old
  1830. threading libraries.
  1831. Enabling this feature adds a small amount of overhead to
  1832. context switches and increases the low-level kernel attack
  1833. surface. Disabling it removes the modify_ldt(2) system call.
  1834. Saying 'N' here may make sense for embedded or server kernels.
  1835. source "kernel/livepatch/Kconfig"
  1836. endmenu
  1837. config ARCH_ENABLE_MEMORY_HOTPLUG
  1838. def_bool y
  1839. depends on X86_64 || (X86_32 && HIGHMEM)
  1840. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1841. def_bool y
  1842. depends on MEMORY_HOTPLUG
  1843. config USE_PERCPU_NUMA_NODE_ID
  1844. def_bool y
  1845. depends on NUMA
  1846. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  1847. def_bool y
  1848. depends on X86_64 || X86_PAE
  1849. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  1850. def_bool y
  1851. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  1852. menu "Power management and ACPI options"
  1853. config ARCH_HIBERNATION_HEADER
  1854. def_bool y
  1855. depends on X86_64 && HIBERNATION
  1856. source "kernel/power/Kconfig"
  1857. source "drivers/acpi/Kconfig"
  1858. source "drivers/sfi/Kconfig"
  1859. config X86_APM_BOOT
  1860. def_bool y
  1861. depends on APM
  1862. menuconfig APM
  1863. tristate "APM (Advanced Power Management) BIOS support"
  1864. depends on X86_32 && PM_SLEEP
  1865. ---help---
  1866. APM is a BIOS specification for saving power using several different
  1867. techniques. This is mostly useful for battery powered laptops with
  1868. APM compliant BIOSes. If you say Y here, the system time will be
  1869. reset after a RESUME operation, the /proc/apm device will provide
  1870. battery status information, and user-space programs will receive
  1871. notification of APM "events" (e.g. battery status change).
  1872. If you select "Y" here, you can disable actual use of the APM
  1873. BIOS by passing the "apm=off" option to the kernel at boot time.
  1874. Note that the APM support is almost completely disabled for
  1875. machines with more than one CPU.
  1876. In order to use APM, you will need supporting software. For location
  1877. and more information, read <file:Documentation/power/apm-acpi.txt>
  1878. and the Battery Powered Linux mini-HOWTO, available from
  1879. <http://www.tldp.org/docs.html#howto>.
  1880. This driver does not spin down disk drives (see the hdparm(8)
  1881. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1882. VESA-compliant "green" monitors.
  1883. This driver does not support the TI 4000M TravelMate and the ACER
  1884. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1885. desktop machines also don't have compliant BIOSes, and this driver
  1886. may cause those machines to panic during the boot phase.
  1887. Generally, if you don't have a battery in your machine, there isn't
  1888. much point in using this driver and you should say N. If you get
  1889. random kernel OOPSes or reboots that don't seem to be related to
  1890. anything, try disabling/enabling this option (or disabling/enabling
  1891. APM in your BIOS).
  1892. Some other things you should try when experiencing seemingly random,
  1893. "weird" problems:
  1894. 1) make sure that you have enough swap space and that it is
  1895. enabled.
  1896. 2) pass the "no-hlt" option to the kernel
  1897. 3) switch on floating point emulation in the kernel and pass
  1898. the "no387" option to the kernel
  1899. 4) pass the "floppy=nodma" option to the kernel
  1900. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1901. all but the first 4 MB of RAM)
  1902. 6) make sure that the CPU is not over clocked.
  1903. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1904. 8) disable the cache from your BIOS settings
  1905. 9) install a fan for the video card or exchange video RAM
  1906. 10) install a better fan for the CPU
  1907. 11) exchange RAM chips
  1908. 12) exchange the motherboard.
  1909. To compile this driver as a module, choose M here: the
  1910. module will be called apm.
  1911. if APM
  1912. config APM_IGNORE_USER_SUSPEND
  1913. bool "Ignore USER SUSPEND"
  1914. ---help---
  1915. This option will ignore USER SUSPEND requests. On machines with a
  1916. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1917. series notebooks, it is necessary to say Y because of a BIOS bug.
  1918. config APM_DO_ENABLE
  1919. bool "Enable PM at boot time"
  1920. ---help---
  1921. Enable APM features at boot time. From page 36 of the APM BIOS
  1922. specification: "When disabled, the APM BIOS does not automatically
  1923. power manage devices, enter the Standby State, enter the Suspend
  1924. State, or take power saving steps in response to CPU Idle calls."
  1925. This driver will make CPU Idle calls when Linux is idle (unless this
  1926. feature is turned off -- see "Do CPU IDLE calls", below). This
  1927. should always save battery power, but more complicated APM features
  1928. will be dependent on your BIOS implementation. You may need to turn
  1929. this option off if your computer hangs at boot time when using APM
  1930. support, or if it beeps continuously instead of suspending. Turn
  1931. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1932. T400CDT. This is off by default since most machines do fine without
  1933. this feature.
  1934. config APM_CPU_IDLE
  1935. depends on CPU_IDLE
  1936. bool "Make CPU Idle calls when idle"
  1937. ---help---
  1938. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1939. On some machines, this can activate improved power savings, such as
  1940. a slowed CPU clock rate, when the machine is idle. These idle calls
  1941. are made after the idle loop has run for some length of time (e.g.,
  1942. 333 mS). On some machines, this will cause a hang at boot time or
  1943. whenever the CPU becomes idle. (On machines with more than one CPU,
  1944. this option does nothing.)
  1945. config APM_DISPLAY_BLANK
  1946. bool "Enable console blanking using APM"
  1947. ---help---
  1948. Enable console blanking using the APM. Some laptops can use this to
  1949. turn off the LCD backlight when the screen blanker of the Linux
  1950. virtual console blanks the screen. Note that this is only used by
  1951. the virtual console screen blanker, and won't turn off the backlight
  1952. when using the X Window system. This also doesn't have anything to
  1953. do with your VESA-compliant power-saving monitor. Further, this
  1954. option doesn't work for all laptops -- it might not turn off your
  1955. backlight at all, or it might print a lot of errors to the console,
  1956. especially if you are using gpm.
  1957. config APM_ALLOW_INTS
  1958. bool "Allow interrupts during APM BIOS calls"
  1959. ---help---
  1960. Normally we disable external interrupts while we are making calls to
  1961. the APM BIOS as a measure to lessen the effects of a badly behaving
  1962. BIOS implementation. The BIOS should reenable interrupts if it
  1963. needs to. Unfortunately, some BIOSes do not -- especially those in
  1964. many of the newer IBM Thinkpads. If you experience hangs when you
  1965. suspend, try setting this to Y. Otherwise, say N.
  1966. endif # APM
  1967. source "drivers/cpufreq/Kconfig"
  1968. source "drivers/cpuidle/Kconfig"
  1969. source "drivers/idle/Kconfig"
  1970. endmenu
  1971. menu "Bus options (PCI etc.)"
  1972. config PCI
  1973. bool "PCI support"
  1974. default y
  1975. ---help---
  1976. Find out whether you have a PCI motherboard. PCI is the name of a
  1977. bus system, i.e. the way the CPU talks to the other stuff inside
  1978. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1979. VESA. If you have PCI, say Y, otherwise N.
  1980. choice
  1981. prompt "PCI access mode"
  1982. depends on X86_32 && PCI
  1983. default PCI_GOANY
  1984. ---help---
  1985. On PCI systems, the BIOS can be used to detect the PCI devices and
  1986. determine their configuration. However, some old PCI motherboards
  1987. have BIOS bugs and may crash if this is done. Also, some embedded
  1988. PCI-based systems don't have any BIOS at all. Linux can also try to
  1989. detect the PCI hardware directly without using the BIOS.
  1990. With this option, you can specify how Linux should detect the
  1991. PCI devices. If you choose "BIOS", the BIOS will be used,
  1992. if you choose "Direct", the BIOS won't be used, and if you
  1993. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1994. If you choose "Any", the kernel will try MMCONFIG, then the
  1995. direct access method and falls back to the BIOS if that doesn't
  1996. work. If unsure, go with the default, which is "Any".
  1997. config PCI_GOBIOS
  1998. bool "BIOS"
  1999. config PCI_GOMMCONFIG
  2000. bool "MMConfig"
  2001. config PCI_GODIRECT
  2002. bool "Direct"
  2003. config PCI_GOOLPC
  2004. bool "OLPC XO-1"
  2005. depends on OLPC
  2006. config PCI_GOANY
  2007. bool "Any"
  2008. endchoice
  2009. config PCI_BIOS
  2010. def_bool y
  2011. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  2012. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  2013. config PCI_DIRECT
  2014. def_bool y
  2015. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  2016. config PCI_MMCONFIG
  2017. def_bool y
  2018. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  2019. config PCI_OLPC
  2020. def_bool y
  2021. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  2022. config PCI_XEN
  2023. def_bool y
  2024. depends on PCI && XEN
  2025. select SWIOTLB_XEN
  2026. config PCI_DOMAINS
  2027. def_bool y
  2028. depends on PCI
  2029. config PCI_MMCONFIG
  2030. bool "Support mmconfig PCI config space access"
  2031. depends on X86_64 && PCI && ACPI
  2032. config PCI_CNB20LE_QUIRK
  2033. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  2034. depends on PCI
  2035. help
  2036. Read the PCI windows out of the CNB20LE host bridge. This allows
  2037. PCI hotplug to work on systems with the CNB20LE chipset which do
  2038. not have ACPI.
  2039. There's no public spec for this chipset, and this functionality
  2040. is known to be incomplete.
  2041. You should say N unless you know you need this.
  2042. source "drivers/pci/Kconfig"
  2043. config ISA_BUS
  2044. bool "ISA-style bus support on modern systems" if EXPERT
  2045. select ISA_BUS_API
  2046. help
  2047. Enables ISA-style drivers on modern systems. This is necessary to
  2048. support PC/104 devices on X86_64 platforms.
  2049. If unsure, say N.
  2050. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2051. config ISA_DMA_API
  2052. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2053. default y
  2054. help
  2055. Enables ISA-style DMA support for devices requiring such controllers.
  2056. If unsure, say Y.
  2057. if X86_32
  2058. config ISA
  2059. bool "ISA support"
  2060. ---help---
  2061. Find out whether you have ISA slots on your motherboard. ISA is the
  2062. name of a bus system, i.e. the way the CPU talks to the other stuff
  2063. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2064. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2065. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2066. config EISA
  2067. bool "EISA support"
  2068. depends on ISA
  2069. ---help---
  2070. The Extended Industry Standard Architecture (EISA) bus was
  2071. developed as an open alternative to the IBM MicroChannel bus.
  2072. The EISA bus provided some of the features of the IBM MicroChannel
  2073. bus while maintaining backward compatibility with cards made for
  2074. the older ISA bus. The EISA bus saw limited use between 1988 and
  2075. 1995 when it was made obsolete by the PCI bus.
  2076. Say Y here if you are building a kernel for an EISA-based machine.
  2077. Otherwise, say N.
  2078. source "drivers/eisa/Kconfig"
  2079. config SCx200
  2080. tristate "NatSemi SCx200 support"
  2081. ---help---
  2082. This provides basic support for National Semiconductor's
  2083. (now AMD's) Geode processors. The driver probes for the
  2084. PCI-IDs of several on-chip devices, so its a good dependency
  2085. for other scx200_* drivers.
  2086. If compiled as a module, the driver is named scx200.
  2087. config SCx200HR_TIMER
  2088. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2089. depends on SCx200
  2090. default y
  2091. ---help---
  2092. This driver provides a clocksource built upon the on-chip
  2093. 27MHz high-resolution timer. Its also a workaround for
  2094. NSC Geode SC-1100's buggy TSC, which loses time when the
  2095. processor goes idle (as is done by the scheduler). The
  2096. other workaround is idle=poll boot option.
  2097. config OLPC
  2098. bool "One Laptop Per Child support"
  2099. depends on !X86_PAE
  2100. select GPIOLIB
  2101. select OF
  2102. select OF_PROMTREE
  2103. select IRQ_DOMAIN
  2104. ---help---
  2105. Add support for detecting the unique features of the OLPC
  2106. XO hardware.
  2107. config OLPC_XO1_PM
  2108. bool "OLPC XO-1 Power Management"
  2109. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2110. select MFD_CORE
  2111. ---help---
  2112. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2113. config OLPC_XO1_RTC
  2114. bool "OLPC XO-1 Real Time Clock"
  2115. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2116. ---help---
  2117. Add support for the XO-1 real time clock, which can be used as a
  2118. programmable wakeup source.
  2119. config OLPC_XO1_SCI
  2120. bool "OLPC XO-1 SCI extras"
  2121. depends on OLPC && OLPC_XO1_PM
  2122. depends on INPUT=y
  2123. select POWER_SUPPLY
  2124. select GPIO_CS5535
  2125. select MFD_CORE
  2126. ---help---
  2127. Add support for SCI-based features of the OLPC XO-1 laptop:
  2128. - EC-driven system wakeups
  2129. - Power button
  2130. - Ebook switch
  2131. - Lid switch
  2132. - AC adapter status updates
  2133. - Battery status updates
  2134. config OLPC_XO15_SCI
  2135. bool "OLPC XO-1.5 SCI extras"
  2136. depends on OLPC && ACPI
  2137. select POWER_SUPPLY
  2138. ---help---
  2139. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2140. - EC-driven system wakeups
  2141. - AC adapter status updates
  2142. - Battery status updates
  2143. config ALIX
  2144. bool "PCEngines ALIX System Support (LED setup)"
  2145. select GPIOLIB
  2146. ---help---
  2147. This option enables system support for the PCEngines ALIX.
  2148. At present this just sets up LEDs for GPIO control on
  2149. ALIX2/3/6 boards. However, other system specific setup should
  2150. get added here.
  2151. Note: You must still enable the drivers for GPIO and LED support
  2152. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2153. Note: You have to set alix.force=1 for boards with Award BIOS.
  2154. config NET5501
  2155. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2156. select GPIOLIB
  2157. ---help---
  2158. This option enables system support for the Soekris Engineering net5501.
  2159. config GEOS
  2160. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2161. select GPIOLIB
  2162. depends on DMI
  2163. ---help---
  2164. This option enables system support for the Traverse Technologies GEOS.
  2165. config TS5500
  2166. bool "Technologic Systems TS-5500 platform support"
  2167. depends on MELAN
  2168. select CHECK_SIGNATURE
  2169. select NEW_LEDS
  2170. select LEDS_CLASS
  2171. ---help---
  2172. This option enables system support for the Technologic Systems TS-5500.
  2173. endif # X86_32
  2174. config AMD_NB
  2175. def_bool y
  2176. depends on CPU_SUP_AMD && PCI
  2177. source "drivers/pcmcia/Kconfig"
  2178. config RAPIDIO
  2179. tristate "RapidIO support"
  2180. depends on PCI
  2181. default n
  2182. help
  2183. If enabled this option will include drivers and the core
  2184. infrastructure code to support RapidIO interconnect devices.
  2185. source "drivers/rapidio/Kconfig"
  2186. config X86_SYSFB
  2187. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2188. help
  2189. Firmwares often provide initial graphics framebuffers so the BIOS,
  2190. bootloader or kernel can show basic video-output during boot for
  2191. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2192. Extensions and EFI-framebuffers for this, which are mostly limited
  2193. to x86.
  2194. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2195. framebuffers so the new generic system-framebuffer drivers can be
  2196. used on x86. If the framebuffer is not compatible with the generic
  2197. modes, it is adverticed as fallback platform framebuffer so legacy
  2198. drivers like efifb, vesafb and uvesafb can pick it up.
  2199. If this option is not selected, all system framebuffers are always
  2200. marked as fallback platform framebuffers as usual.
  2201. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2202. not be able to pick up generic system framebuffers if this option
  2203. is selected. You are highly encouraged to enable simplefb as
  2204. replacement if you select this option. simplefb can correctly deal
  2205. with generic system framebuffers. But you should still keep vesafb
  2206. and others enabled as fallback if a system framebuffer is
  2207. incompatible with simplefb.
  2208. If unsure, say Y.
  2209. endmenu
  2210. menu "Executable file formats / Emulations"
  2211. source "fs/Kconfig.binfmt"
  2212. config IA32_EMULATION
  2213. bool "IA32 Emulation"
  2214. depends on X86_64
  2215. select BINFMT_ELF
  2216. select COMPAT_BINFMT_ELF
  2217. select ARCH_WANT_OLD_COMPAT_IPC
  2218. ---help---
  2219. Include code to run legacy 32-bit programs under a
  2220. 64-bit kernel. You should likely turn this on, unless you're
  2221. 100% sure that you don't have any 32-bit programs left.
  2222. config IA32_AOUT
  2223. tristate "IA32 a.out support"
  2224. depends on IA32_EMULATION
  2225. ---help---
  2226. Support old a.out binaries in the 32bit emulation.
  2227. config X86_X32
  2228. bool "x32 ABI for 64-bit mode"
  2229. depends on X86_64
  2230. ---help---
  2231. Include code to run binaries for the x32 native 32-bit ABI
  2232. for 64-bit processors. An x32 process gets access to the
  2233. full 64-bit register file and wide data path while leaving
  2234. pointers at 32 bits for smaller memory footprint.
  2235. You will need a recent binutils (2.22 or later) with
  2236. elf32_x86_64 support enabled to compile a kernel with this
  2237. option set.
  2238. config COMPAT
  2239. def_bool y
  2240. depends on IA32_EMULATION || X86_X32
  2241. if COMPAT
  2242. config COMPAT_FOR_U64_ALIGNMENT
  2243. def_bool y
  2244. config SYSVIPC_COMPAT
  2245. def_bool y
  2246. depends on SYSVIPC
  2247. config KEYS_COMPAT
  2248. def_bool y
  2249. depends on KEYS
  2250. endif
  2251. endmenu
  2252. config HAVE_ATOMIC_IOMAP
  2253. def_bool y
  2254. depends on X86_32
  2255. config X86_DEV_DMA_OPS
  2256. bool
  2257. depends on X86_64 || STA2X11
  2258. config X86_DMA_REMAP
  2259. bool
  2260. depends on STA2X11
  2261. config PMC_ATOM
  2262. def_bool y
  2263. depends on PCI
  2264. config VMD
  2265. depends on PCI_MSI
  2266. tristate "Volume Management Device Driver"
  2267. default N
  2268. ---help---
  2269. Adds support for the Intel Volume Management Device (VMD). VMD is a
  2270. secondary PCI host bridge that allows PCI Express root ports,
  2271. and devices attached to them, to be removed from the default
  2272. PCI domain and placed within the VMD domain. This provides
  2273. more bus resources than are otherwise possible with a
  2274. single domain. If you know your system provides one of these and
  2275. has devices attached to it, say Y; if you are not sure, say N.
  2276. source "net/Kconfig"
  2277. source "drivers/Kconfig"
  2278. source "drivers/firmware/Kconfig"
  2279. source "fs/Kconfig"
  2280. source "arch/x86/Kconfig.debug"
  2281. source "security/Kconfig"
  2282. source "crypto/Kconfig"
  2283. source "arch/x86/kvm/Kconfig"
  2284. source "lib/Kconfig"