Kconfig 90 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. # Options that are inherently 32-bit kernel only:
  12. select ARCH_WANT_IPC_PARSE_VERSION
  13. select CLKSRC_I8253
  14. select CLONE_BACKWARDS
  15. select HAVE_AOUT
  16. select HAVE_GENERIC_DMA_COHERENT
  17. select MODULES_USE_ELF_REL
  18. select OLD_SIGACTION
  19. config X86_64
  20. def_bool y
  21. depends on 64BIT
  22. # Options that are inherently 64-bit kernel only:
  23. select ARCH_HAS_GIGANTIC_PAGE
  24. select ARCH_SUPPORTS_INT128
  25. select ARCH_USE_CMPXCHG_LOCKREF
  26. select HAVE_ARCH_SOFT_DIRTY
  27. select MODULES_USE_ELF_RELA
  28. select X86_DEV_DMA_OPS
  29. #
  30. # Arch settings
  31. #
  32. # ( Note that options that are marked 'if X86_64' could in principle be
  33. # ported to 32-bit as well. )
  34. #
  35. config X86
  36. def_bool y
  37. #
  38. # Note: keep this list sorted alphabetically
  39. #
  40. select ACPI_LEGACY_TABLES_LOOKUP if ACPI
  41. select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
  42. select ANON_INODES
  43. select ARCH_CLOCKSOURCE_DATA
  44. select ARCH_DISCARD_MEMBLOCK
  45. select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
  46. select ARCH_HAS_DEBUG_VIRTUAL
  47. select ARCH_HAS_DEVMEM_IS_ALLOWED
  48. select ARCH_HAS_ELF_RANDOMIZE
  49. select ARCH_HAS_FAST_MULTIPLIER
  50. select ARCH_HAS_GCOV_PROFILE_ALL
  51. select ARCH_HAS_KCOV if X86_64
  52. select ARCH_HAS_MMIO_FLUSH
  53. select ARCH_HAS_PMEM_API if X86_64
  54. select ARCH_HAS_SET_MEMORY
  55. select ARCH_HAS_SG_CHAIN
  56. select ARCH_HAS_STRICT_KERNEL_RWX
  57. select ARCH_HAS_STRICT_MODULE_RWX
  58. select ARCH_HAS_UBSAN_SANITIZE_ALL
  59. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  60. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  61. select ARCH_MIGHT_HAVE_PC_PARPORT
  62. select ARCH_MIGHT_HAVE_PC_SERIO
  63. select ARCH_SUPPORTS_ATOMIC_RMW
  64. select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
  65. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  66. select ARCH_USE_BUILTIN_BSWAP
  67. select ARCH_USE_QUEUED_RWLOCKS
  68. select ARCH_USE_QUEUED_SPINLOCKS
  69. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
  70. select ARCH_WANT_FRAME_POINTERS
  71. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  72. select BUILDTIME_EXTABLE_SORT
  73. select CLKEVT_I8253
  74. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  75. select CLOCKSOURCE_WATCHDOG
  76. select DCACHE_WORD_ACCESS
  77. select EDAC_ATOMIC_SCRUB
  78. select EDAC_SUPPORT
  79. select GENERIC_CLOCKEVENTS
  80. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  81. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  82. select GENERIC_CMOS_UPDATE
  83. select GENERIC_CPU_AUTOPROBE
  84. select GENERIC_EARLY_IOREMAP
  85. select GENERIC_FIND_FIRST_BIT
  86. select GENERIC_IOMAP
  87. select GENERIC_IRQ_PROBE
  88. select GENERIC_IRQ_SHOW
  89. select GENERIC_PENDING_IRQ if SMP
  90. select GENERIC_SMP_IDLE_THREAD
  91. select GENERIC_STRNCPY_FROM_USER
  92. select GENERIC_STRNLEN_USER
  93. select GENERIC_TIME_VSYSCALL
  94. select HAVE_ACPI_APEI if ACPI
  95. select HAVE_ACPI_APEI_NMI if ACPI
  96. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  97. select HAVE_ARCH_AUDITSYSCALL
  98. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  99. select HAVE_ARCH_JUMP_LABEL
  100. select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
  101. select HAVE_ARCH_KGDB
  102. select HAVE_ARCH_KMEMCHECK
  103. select HAVE_ARCH_MMAP_RND_BITS if MMU
  104. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
  105. select HAVE_ARCH_SECCOMP_FILTER
  106. select HAVE_ARCH_TRACEHOOK
  107. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  108. select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
  109. select HAVE_ARCH_VMAP_STACK if X86_64
  110. select HAVE_ARCH_WITHIN_STACK_FRAMES
  111. select HAVE_CC_STACKPROTECTOR
  112. select HAVE_CMPXCHG_DOUBLE
  113. select HAVE_CMPXCHG_LOCAL
  114. select HAVE_CONTEXT_TRACKING if X86_64
  115. select HAVE_COPY_THREAD_TLS
  116. select HAVE_C_RECORDMCOUNT
  117. select HAVE_DEBUG_KMEMLEAK
  118. select HAVE_DEBUG_STACKOVERFLOW
  119. select HAVE_DMA_API_DEBUG
  120. select HAVE_DMA_CONTIGUOUS
  121. select HAVE_DYNAMIC_FTRACE
  122. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  123. select HAVE_EBPF_JIT if X86_64
  124. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  125. select HAVE_EXIT_THREAD
  126. select HAVE_FENTRY if X86_64
  127. select HAVE_FTRACE_MCOUNT_RECORD
  128. select HAVE_FUNCTION_GRAPH_TRACER
  129. select HAVE_FUNCTION_TRACER
  130. select HAVE_GCC_PLUGINS
  131. select HAVE_HW_BREAKPOINT
  132. select HAVE_IDE
  133. select HAVE_IOREMAP_PROT
  134. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  135. select HAVE_IRQ_TIME_ACCOUNTING
  136. select HAVE_KERNEL_BZIP2
  137. select HAVE_KERNEL_GZIP
  138. select HAVE_KERNEL_LZ4
  139. select HAVE_KERNEL_LZMA
  140. select HAVE_KERNEL_LZO
  141. select HAVE_KERNEL_XZ
  142. select HAVE_KPROBES
  143. select HAVE_KPROBES_ON_FTRACE
  144. select HAVE_KRETPROBES
  145. select HAVE_KVM
  146. select HAVE_LIVEPATCH if X86_64
  147. select HAVE_MEMBLOCK
  148. select HAVE_MEMBLOCK_NODE_MAP
  149. select HAVE_MIXED_BREAKPOINTS_REGS
  150. select HAVE_NMI
  151. select HAVE_OPROFILE
  152. select HAVE_OPTPROBES
  153. select HAVE_PCSPKR_PLATFORM
  154. select HAVE_PERF_EVENTS
  155. select HAVE_PERF_EVENTS_NMI
  156. select HAVE_PERF_REGS
  157. select HAVE_PERF_USER_STACK_DUMP
  158. select HAVE_REGS_AND_STACK_ACCESS_API
  159. select HAVE_STACK_VALIDATION if X86_64
  160. select HAVE_SYSCALL_TRACEPOINTS
  161. select HAVE_UNSTABLE_SCHED_CLOCK
  162. select HAVE_USER_RETURN_NOTIFIER
  163. select IRQ_FORCED_THREADING
  164. select PERF_EVENTS
  165. select RTC_LIB
  166. select RTC_MC146818_LIB
  167. select SPARSE_IRQ
  168. select SRCU
  169. select SYSCTL_EXCEPTION_TRACE
  170. select THREAD_INFO_IN_TASK
  171. select USER_STACKTRACE_SUPPORT
  172. select VIRT_TO_BUS
  173. select X86_FEATURE_NAMES if PROC_FS
  174. config INSTRUCTION_DECODER
  175. def_bool y
  176. depends on KPROBES || PERF_EVENTS || UPROBES
  177. config OUTPUT_FORMAT
  178. string
  179. default "elf32-i386" if X86_32
  180. default "elf64-x86-64" if X86_64
  181. config ARCH_DEFCONFIG
  182. string
  183. default "arch/x86/configs/i386_defconfig" if X86_32
  184. default "arch/x86/configs/x86_64_defconfig" if X86_64
  185. config LOCKDEP_SUPPORT
  186. def_bool y
  187. config STACKTRACE_SUPPORT
  188. def_bool y
  189. config MMU
  190. def_bool y
  191. config ARCH_MMAP_RND_BITS_MIN
  192. default 28 if 64BIT
  193. default 8
  194. config ARCH_MMAP_RND_BITS_MAX
  195. default 32 if 64BIT
  196. default 16
  197. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  198. default 8
  199. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  200. default 16
  201. config SBUS
  202. bool
  203. config NEED_DMA_MAP_STATE
  204. def_bool y
  205. depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
  206. config NEED_SG_DMA_LENGTH
  207. def_bool y
  208. config GENERIC_ISA_DMA
  209. def_bool y
  210. depends on ISA_DMA_API
  211. config GENERIC_BUG
  212. def_bool y
  213. depends on BUG
  214. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  215. config GENERIC_BUG_RELATIVE_POINTERS
  216. bool
  217. config GENERIC_HWEIGHT
  218. def_bool y
  219. config ARCH_MAY_HAVE_PC_FDC
  220. def_bool y
  221. depends on ISA_DMA_API
  222. config RWSEM_XCHGADD_ALGORITHM
  223. def_bool y
  224. config GENERIC_CALIBRATE_DELAY
  225. def_bool y
  226. config ARCH_HAS_CPU_RELAX
  227. def_bool y
  228. config ARCH_HAS_CACHE_LINE_SIZE
  229. def_bool y
  230. config HAVE_SETUP_PER_CPU_AREA
  231. def_bool y
  232. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  233. def_bool y
  234. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  235. def_bool y
  236. config ARCH_HIBERNATION_POSSIBLE
  237. def_bool y
  238. config ARCH_SUSPEND_POSSIBLE
  239. def_bool y
  240. config ARCH_WANT_HUGE_PMD_SHARE
  241. def_bool y
  242. config ARCH_WANT_GENERAL_HUGETLB
  243. def_bool y
  244. config ZONE_DMA32
  245. def_bool y if X86_64
  246. config AUDIT_ARCH
  247. def_bool y if X86_64
  248. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  249. def_bool y
  250. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  251. def_bool y
  252. config KASAN_SHADOW_OFFSET
  253. hex
  254. depends on KASAN
  255. default 0xdffffc0000000000
  256. config HAVE_INTEL_TXT
  257. def_bool y
  258. depends on INTEL_IOMMU && ACPI
  259. config X86_32_SMP
  260. def_bool y
  261. depends on X86_32 && SMP
  262. config X86_64_SMP
  263. def_bool y
  264. depends on X86_64 && SMP
  265. config X86_32_LAZY_GS
  266. def_bool y
  267. depends on X86_32 && !CC_STACKPROTECTOR
  268. config ARCH_SUPPORTS_UPROBES
  269. def_bool y
  270. config FIX_EARLYCON_MEM
  271. def_bool y
  272. config PGTABLE_LEVELS
  273. int
  274. default 4 if X86_64
  275. default 3 if X86_PAE
  276. default 2
  277. source "init/Kconfig"
  278. source "kernel/Kconfig.freezer"
  279. menu "Processor type and features"
  280. config ZONE_DMA
  281. bool "DMA memory allocation support" if EXPERT
  282. default y
  283. help
  284. DMA memory allocation support allows devices with less than 32-bit
  285. addressing to allocate within the first 16MB of address space.
  286. Disable if no such devices will be used.
  287. If unsure, say Y.
  288. config SMP
  289. bool "Symmetric multi-processing support"
  290. ---help---
  291. This enables support for systems with more than one CPU. If you have
  292. a system with only one CPU, say N. If you have a system with more
  293. than one CPU, say Y.
  294. If you say N here, the kernel will run on uni- and multiprocessor
  295. machines, but will use only one CPU of a multiprocessor machine. If
  296. you say Y here, the kernel will run on many, but not all,
  297. uniprocessor machines. On a uniprocessor machine, the kernel
  298. will run faster if you say N here.
  299. Note that if you say Y here and choose architecture "586" or
  300. "Pentium" under "Processor family", the kernel will not work on 486
  301. architectures. Similarly, multiprocessor kernels for the "PPro"
  302. architecture may not work on all Pentium based boards.
  303. People using multiprocessor machines who say Y here should also say
  304. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  305. Management" code will be disabled if you say Y here.
  306. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  307. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  308. <http://www.tldp.org/docs.html#howto>.
  309. If you don't know what to do here, say N.
  310. config X86_FEATURE_NAMES
  311. bool "Processor feature human-readable names" if EMBEDDED
  312. default y
  313. ---help---
  314. This option compiles in a table of x86 feature bits and corresponding
  315. names. This is required to support /proc/cpuinfo and a few kernel
  316. messages. You can disable this to save space, at the expense of
  317. making those few kernel messages show numeric feature bits instead.
  318. If in doubt, say Y.
  319. config X86_FAST_FEATURE_TESTS
  320. bool "Fast CPU feature tests" if EMBEDDED
  321. default y
  322. ---help---
  323. Some fast-paths in the kernel depend on the capabilities of the CPU.
  324. Say Y here for the kernel to patch in the appropriate code at runtime
  325. based on the capabilities of the CPU. The infrastructure for patching
  326. code at runtime takes up some additional space; space-constrained
  327. embedded systems may wish to say N here to produce smaller, slightly
  328. slower code.
  329. config X86_X2APIC
  330. bool "Support x2apic"
  331. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  332. ---help---
  333. This enables x2apic support on CPUs that have this feature.
  334. This allows 32-bit apic IDs (so it can support very large systems),
  335. and accesses the local apic via MSRs not via mmio.
  336. If you don't know what to do here, say N.
  337. config X86_MPPARSE
  338. bool "Enable MPS table" if ACPI || SFI
  339. default y
  340. depends on X86_LOCAL_APIC
  341. ---help---
  342. For old smp systems that do not have proper acpi support. Newer systems
  343. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  344. config X86_BIGSMP
  345. bool "Support for big SMP systems with more than 8 CPUs"
  346. depends on X86_32 && SMP
  347. ---help---
  348. This option is needed for the systems that have more than 8 CPUs
  349. config GOLDFISH
  350. def_bool y
  351. depends on X86_GOLDFISH
  352. config INTEL_RDT_A
  353. bool "Intel Resource Director Technology Allocation support"
  354. default n
  355. depends on X86 && CPU_SUP_INTEL
  356. select KERNFS
  357. help
  358. Select to enable resource allocation which is a sub-feature of
  359. Intel Resource Director Technology(RDT). More information about
  360. RDT can be found in the Intel x86 Architecture Software
  361. Developer Manual.
  362. Say N if unsure.
  363. if X86_32
  364. config X86_EXTENDED_PLATFORM
  365. bool "Support for extended (non-PC) x86 platforms"
  366. default y
  367. ---help---
  368. If you disable this option then the kernel will only support
  369. standard PC platforms. (which covers the vast majority of
  370. systems out there.)
  371. If you enable this option then you'll be able to select support
  372. for the following (non-PC) 32 bit x86 platforms:
  373. Goldfish (Android emulator)
  374. AMD Elan
  375. RDC R-321x SoC
  376. SGI 320/540 (Visual Workstation)
  377. STA2X11-based (e.g. Northville)
  378. Moorestown MID devices
  379. If you have one of these systems, or if you want to build a
  380. generic distribution kernel, say Y here - otherwise say N.
  381. endif
  382. if X86_64
  383. config X86_EXTENDED_PLATFORM
  384. bool "Support for extended (non-PC) x86 platforms"
  385. default y
  386. ---help---
  387. If you disable this option then the kernel will only support
  388. standard PC platforms. (which covers the vast majority of
  389. systems out there.)
  390. If you enable this option then you'll be able to select support
  391. for the following (non-PC) 64 bit x86 platforms:
  392. Numascale NumaChip
  393. ScaleMP vSMP
  394. SGI Ultraviolet
  395. If you have one of these systems, or if you want to build a
  396. generic distribution kernel, say Y here - otherwise say N.
  397. endif
  398. # This is an alphabetically sorted list of 64 bit extended platforms
  399. # Please maintain the alphabetic order if and when there are additions
  400. config X86_NUMACHIP
  401. bool "Numascale NumaChip"
  402. depends on X86_64
  403. depends on X86_EXTENDED_PLATFORM
  404. depends on NUMA
  405. depends on SMP
  406. depends on X86_X2APIC
  407. depends on PCI_MMCONFIG
  408. ---help---
  409. Adds support for Numascale NumaChip large-SMP systems. Needed to
  410. enable more than ~168 cores.
  411. If you don't have one of these, you should say N here.
  412. config X86_VSMP
  413. bool "ScaleMP vSMP"
  414. select HYPERVISOR_GUEST
  415. select PARAVIRT
  416. depends on X86_64 && PCI
  417. depends on X86_EXTENDED_PLATFORM
  418. depends on SMP
  419. ---help---
  420. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  421. supposed to run on these EM64T-based machines. Only choose this option
  422. if you have one of these machines.
  423. config X86_UV
  424. bool "SGI Ultraviolet"
  425. depends on X86_64
  426. depends on X86_EXTENDED_PLATFORM
  427. depends on NUMA
  428. depends on EFI
  429. depends on X86_X2APIC
  430. depends on PCI
  431. ---help---
  432. This option is needed in order to support SGI Ultraviolet systems.
  433. If you don't have one of these, you should say N here.
  434. # Following is an alphabetically sorted list of 32 bit extended platforms
  435. # Please maintain the alphabetic order if and when there are additions
  436. config X86_GOLDFISH
  437. bool "Goldfish (Virtual Platform)"
  438. depends on X86_EXTENDED_PLATFORM
  439. ---help---
  440. Enable support for the Goldfish virtual platform used primarily
  441. for Android development. Unless you are building for the Android
  442. Goldfish emulator say N here.
  443. config X86_INTEL_CE
  444. bool "CE4100 TV platform"
  445. depends on PCI
  446. depends on PCI_GODIRECT
  447. depends on X86_IO_APIC
  448. depends on X86_32
  449. depends on X86_EXTENDED_PLATFORM
  450. select X86_REBOOTFIXUPS
  451. select OF
  452. select OF_EARLY_FLATTREE
  453. ---help---
  454. Select for the Intel CE media processor (CE4100) SOC.
  455. This option compiles in support for the CE4100 SOC for settop
  456. boxes and media devices.
  457. config X86_INTEL_MID
  458. bool "Intel MID platform support"
  459. depends on X86_EXTENDED_PLATFORM
  460. depends on X86_PLATFORM_DEVICES
  461. depends on PCI
  462. depends on X86_64 || (PCI_GOANY && X86_32)
  463. depends on X86_IO_APIC
  464. select SFI
  465. select I2C
  466. select DW_APB_TIMER
  467. select APB_TIMER
  468. select INTEL_SCU_IPC
  469. select MFD_INTEL_MSIC
  470. ---help---
  471. Select to build a kernel capable of supporting Intel MID (Mobile
  472. Internet Device) platform systems which do not have the PCI legacy
  473. interfaces. If you are building for a PC class system say N here.
  474. Intel MID platforms are based on an Intel processor and chipset which
  475. consume less power than most of the x86 derivatives.
  476. config X86_INTEL_QUARK
  477. bool "Intel Quark platform support"
  478. depends on X86_32
  479. depends on X86_EXTENDED_PLATFORM
  480. depends on X86_PLATFORM_DEVICES
  481. depends on X86_TSC
  482. depends on PCI
  483. depends on PCI_GOANY
  484. depends on X86_IO_APIC
  485. select IOSF_MBI
  486. select INTEL_IMR
  487. select COMMON_CLK
  488. ---help---
  489. Select to include support for Quark X1000 SoC.
  490. Say Y here if you have a Quark based system such as the Arduino
  491. compatible Intel Galileo.
  492. config X86_INTEL_LPSS
  493. bool "Intel Low Power Subsystem Support"
  494. depends on X86 && ACPI
  495. select COMMON_CLK
  496. select PINCTRL
  497. select IOSF_MBI
  498. ---help---
  499. Select to build support for Intel Low Power Subsystem such as
  500. found on Intel Lynxpoint PCH. Selecting this option enables
  501. things like clock tree (common clock framework) and pincontrol
  502. which are needed by the LPSS peripheral drivers.
  503. config X86_AMD_PLATFORM_DEVICE
  504. bool "AMD ACPI2Platform devices support"
  505. depends on ACPI
  506. select COMMON_CLK
  507. select PINCTRL
  508. ---help---
  509. Select to interpret AMD specific ACPI device to platform device
  510. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  511. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  512. implemented under PINCTRL subsystem.
  513. config IOSF_MBI
  514. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  515. depends on PCI
  516. ---help---
  517. This option enables sideband register access support for Intel SoC
  518. platforms. On these platforms the IOSF sideband is used in lieu of
  519. MSR's for some register accesses, mostly but not limited to thermal
  520. and power. Drivers may query the availability of this device to
  521. determine if they need the sideband in order to work on these
  522. platforms. The sideband is available on the following SoC products.
  523. This list is not meant to be exclusive.
  524. - BayTrail
  525. - Braswell
  526. - Quark
  527. You should say Y if you are running a kernel on one of these SoC's.
  528. config IOSF_MBI_DEBUG
  529. bool "Enable IOSF sideband access through debugfs"
  530. depends on IOSF_MBI && DEBUG_FS
  531. ---help---
  532. Select this option to expose the IOSF sideband access registers (MCR,
  533. MDR, MCRX) through debugfs to write and read register information from
  534. different units on the SoC. This is most useful for obtaining device
  535. state information for debug and analysis. As this is a general access
  536. mechanism, users of this option would have specific knowledge of the
  537. device they want to access.
  538. If you don't require the option or are in doubt, say N.
  539. config X86_RDC321X
  540. bool "RDC R-321x SoC"
  541. depends on X86_32
  542. depends on X86_EXTENDED_PLATFORM
  543. select M486
  544. select X86_REBOOTFIXUPS
  545. ---help---
  546. This option is needed for RDC R-321x system-on-chip, also known
  547. as R-8610-(G).
  548. If you don't have one of these chips, you should say N here.
  549. config X86_32_NON_STANDARD
  550. bool "Support non-standard 32-bit SMP architectures"
  551. depends on X86_32 && SMP
  552. depends on X86_EXTENDED_PLATFORM
  553. ---help---
  554. This option compiles in the bigsmp and STA2X11 default
  555. subarchitectures. It is intended for a generic binary
  556. kernel. If you select them all, kernel will probe it one by
  557. one and will fallback to default.
  558. # Alphabetically sorted list of Non standard 32 bit platforms
  559. config X86_SUPPORTS_MEMORY_FAILURE
  560. def_bool y
  561. # MCE code calls memory_failure():
  562. depends on X86_MCE
  563. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  564. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  565. depends on X86_64 || !SPARSEMEM
  566. select ARCH_SUPPORTS_MEMORY_FAILURE
  567. config STA2X11
  568. bool "STA2X11 Companion Chip Support"
  569. depends on X86_32_NON_STANDARD && PCI
  570. select X86_DEV_DMA_OPS
  571. select X86_DMA_REMAP
  572. select SWIOTLB
  573. select MFD_STA2X11
  574. select GPIOLIB
  575. default n
  576. ---help---
  577. This adds support for boards based on the STA2X11 IO-Hub,
  578. a.k.a. "ConneXt". The chip is used in place of the standard
  579. PC chipset, so all "standard" peripherals are missing. If this
  580. option is selected the kernel will still be able to boot on
  581. standard PC machines.
  582. config X86_32_IRIS
  583. tristate "Eurobraille/Iris poweroff module"
  584. depends on X86_32
  585. ---help---
  586. The Iris machines from EuroBraille do not have APM or ACPI support
  587. to shut themselves down properly. A special I/O sequence is
  588. needed to do so, which is what this module does at
  589. kernel shutdown.
  590. This is only for Iris machines from EuroBraille.
  591. If unused, say N.
  592. config SCHED_OMIT_FRAME_POINTER
  593. def_bool y
  594. prompt "Single-depth WCHAN output"
  595. depends on X86
  596. ---help---
  597. Calculate simpler /proc/<PID>/wchan values. If this option
  598. is disabled then wchan values will recurse back to the
  599. caller function. This provides more accurate wchan values,
  600. at the expense of slightly more scheduling overhead.
  601. If in doubt, say "Y".
  602. menuconfig HYPERVISOR_GUEST
  603. bool "Linux guest support"
  604. ---help---
  605. Say Y here to enable options for running Linux under various hyper-
  606. visors. This option enables basic hypervisor detection and platform
  607. setup.
  608. If you say N, all options in this submenu will be skipped and
  609. disabled, and Linux guest support won't be built in.
  610. if HYPERVISOR_GUEST
  611. config PARAVIRT
  612. bool "Enable paravirtualization code"
  613. ---help---
  614. This changes the kernel so it can modify itself when it is run
  615. under a hypervisor, potentially improving performance significantly
  616. over full virtualization. However, when run without a hypervisor
  617. the kernel is theoretically slower and slightly larger.
  618. config PARAVIRT_DEBUG
  619. bool "paravirt-ops debugging"
  620. depends on PARAVIRT && DEBUG_KERNEL
  621. ---help---
  622. Enable to debug paravirt_ops internals. Specifically, BUG if
  623. a paravirt_op is missing when it is called.
  624. config PARAVIRT_SPINLOCKS
  625. bool "Paravirtualization layer for spinlocks"
  626. depends on PARAVIRT && SMP
  627. ---help---
  628. Paravirtualized spinlocks allow a pvops backend to replace the
  629. spinlock implementation with something virtualization-friendly
  630. (for example, block the virtual CPU rather than spinning).
  631. It has a minimal impact on native kernels and gives a nice performance
  632. benefit on paravirtualized KVM / Xen kernels.
  633. If you are unsure how to answer this question, answer Y.
  634. config QUEUED_LOCK_STAT
  635. bool "Paravirt queued spinlock statistics"
  636. depends on PARAVIRT_SPINLOCKS && DEBUG_FS
  637. ---help---
  638. Enable the collection of statistical data on the slowpath
  639. behavior of paravirtualized queued spinlocks and report
  640. them on debugfs.
  641. source "arch/x86/xen/Kconfig"
  642. config KVM_GUEST
  643. bool "KVM Guest support (including kvmclock)"
  644. depends on PARAVIRT
  645. select PARAVIRT_CLOCK
  646. default y
  647. ---help---
  648. This option enables various optimizations for running under the KVM
  649. hypervisor. It includes a paravirtualized clock, so that instead
  650. of relying on a PIT (or probably other) emulation by the
  651. underlying device model, the host provides the guest with
  652. timing infrastructure such as time of day, and system time
  653. config KVM_DEBUG_FS
  654. bool "Enable debug information for KVM Guests in debugfs"
  655. depends on KVM_GUEST && DEBUG_FS
  656. default n
  657. ---help---
  658. This option enables collection of various statistics for KVM guest.
  659. Statistics are displayed in debugfs filesystem. Enabling this option
  660. may incur significant overhead.
  661. source "arch/x86/lguest/Kconfig"
  662. config PARAVIRT_TIME_ACCOUNTING
  663. bool "Paravirtual steal time accounting"
  664. depends on PARAVIRT
  665. default n
  666. ---help---
  667. Select this option to enable fine granularity task steal time
  668. accounting. Time spent executing other tasks in parallel with
  669. the current vCPU is discounted from the vCPU power. To account for
  670. that, there can be a small performance impact.
  671. If in doubt, say N here.
  672. config PARAVIRT_CLOCK
  673. bool
  674. endif #HYPERVISOR_GUEST
  675. config NO_BOOTMEM
  676. def_bool y
  677. source "arch/x86/Kconfig.cpu"
  678. config HPET_TIMER
  679. def_bool X86_64
  680. prompt "HPET Timer Support" if X86_32
  681. ---help---
  682. Use the IA-PC HPET (High Precision Event Timer) to manage
  683. time in preference to the PIT and RTC, if a HPET is
  684. present.
  685. HPET is the next generation timer replacing legacy 8254s.
  686. The HPET provides a stable time base on SMP
  687. systems, unlike the TSC, but it is more expensive to access,
  688. as it is off-chip. The interface used is documented
  689. in the HPET spec, revision 1.
  690. You can safely choose Y here. However, HPET will only be
  691. activated if the platform and the BIOS support this feature.
  692. Otherwise the 8254 will be used for timing services.
  693. Choose N to continue using the legacy 8254 timer.
  694. config HPET_EMULATE_RTC
  695. def_bool y
  696. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  697. config APB_TIMER
  698. def_bool y if X86_INTEL_MID
  699. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  700. select DW_APB_TIMER
  701. depends on X86_INTEL_MID && SFI
  702. help
  703. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  704. The APBT provides a stable time base on SMP
  705. systems, unlike the TSC, but it is more expensive to access,
  706. as it is off-chip. APB timers are always running regardless of CPU
  707. C states, they are used as per CPU clockevent device when possible.
  708. # Mark as expert because too many people got it wrong.
  709. # The code disables itself when not needed.
  710. config DMI
  711. default y
  712. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  713. bool "Enable DMI scanning" if EXPERT
  714. ---help---
  715. Enabled scanning of DMI to identify machine quirks. Say Y
  716. here unless you have verified that your setup is not
  717. affected by entries in the DMI blacklist. Required by PNP
  718. BIOS code.
  719. config GART_IOMMU
  720. bool "Old AMD GART IOMMU support"
  721. select SWIOTLB
  722. depends on X86_64 && PCI && AMD_NB
  723. ---help---
  724. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  725. GART based hardware IOMMUs.
  726. The GART supports full DMA access for devices with 32-bit access
  727. limitations, on systems with more than 3 GB. This is usually needed
  728. for USB, sound, many IDE/SATA chipsets and some other devices.
  729. Newer systems typically have a modern AMD IOMMU, supported via
  730. the CONFIG_AMD_IOMMU=y config option.
  731. In normal configurations this driver is only active when needed:
  732. there's more than 3 GB of memory and the system contains a
  733. 32-bit limited device.
  734. If unsure, say Y.
  735. config CALGARY_IOMMU
  736. bool "IBM Calgary IOMMU support"
  737. select SWIOTLB
  738. depends on X86_64 && PCI
  739. ---help---
  740. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  741. systems. Needed to run systems with more than 3GB of memory
  742. properly with 32-bit PCI devices that do not support DAC
  743. (Double Address Cycle). Calgary also supports bus level
  744. isolation, where all DMAs pass through the IOMMU. This
  745. prevents them from going anywhere except their intended
  746. destination. This catches hard-to-find kernel bugs and
  747. mis-behaving drivers and devices that do not use the DMA-API
  748. properly to set up their DMA buffers. The IOMMU can be
  749. turned off at boot time with the iommu=off parameter.
  750. Normally the kernel will make the right choice by itself.
  751. If unsure, say Y.
  752. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  753. def_bool y
  754. prompt "Should Calgary be enabled by default?"
  755. depends on CALGARY_IOMMU
  756. ---help---
  757. Should Calgary be enabled by default? if you choose 'y', Calgary
  758. will be used (if it exists). If you choose 'n', Calgary will not be
  759. used even if it exists. If you choose 'n' and would like to use
  760. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  761. If unsure, say Y.
  762. # need this always selected by IOMMU for the VIA workaround
  763. config SWIOTLB
  764. def_bool y if X86_64
  765. ---help---
  766. Support for software bounce buffers used on x86-64 systems
  767. which don't have a hardware IOMMU. Using this PCI devices
  768. which can only access 32-bits of memory can be used on systems
  769. with more than 3 GB of memory.
  770. If unsure, say Y.
  771. config IOMMU_HELPER
  772. def_bool y
  773. depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
  774. config MAXSMP
  775. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  776. depends on X86_64 && SMP && DEBUG_KERNEL
  777. select CPUMASK_OFFSTACK
  778. ---help---
  779. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  780. If unsure, say N.
  781. config NR_CPUS
  782. int "Maximum number of CPUs" if SMP && !MAXSMP
  783. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  784. range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
  785. range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
  786. default "1" if !SMP
  787. default "8192" if MAXSMP
  788. default "32" if SMP && X86_BIGSMP
  789. default "8" if SMP && X86_32
  790. default "64" if SMP
  791. ---help---
  792. This allows you to specify the maximum number of CPUs which this
  793. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  794. supported value is 8192, otherwise the maximum value is 512. The
  795. minimum value which makes sense is 2.
  796. This is purely to save memory - each supported CPU adds
  797. approximately eight kilobytes to the kernel image.
  798. config SCHED_SMT
  799. bool "SMT (Hyperthreading) scheduler support"
  800. depends on SMP
  801. ---help---
  802. SMT scheduler support improves the CPU scheduler's decision making
  803. when dealing with Intel Pentium 4 chips with HyperThreading at a
  804. cost of slightly increased overhead in some places. If unsure say
  805. N here.
  806. config SCHED_MC
  807. def_bool y
  808. prompt "Multi-core scheduler support"
  809. depends on SMP
  810. ---help---
  811. Multi-core scheduler support improves the CPU scheduler's decision
  812. making when dealing with multi-core CPU chips at a cost of slightly
  813. increased overhead in some places. If unsure say N here.
  814. config SCHED_MC_PRIO
  815. bool "CPU core priorities scheduler support"
  816. depends on SCHED_MC && CPU_SUP_INTEL
  817. select X86_INTEL_PSTATE
  818. select CPU_FREQ
  819. default y
  820. ---help---
  821. Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
  822. core ordering determined at manufacturing time, which allows
  823. certain cores to reach higher turbo frequencies (when running
  824. single threaded workloads) than others.
  825. Enabling this kernel feature teaches the scheduler about
  826. the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
  827. scheduler's CPU selection logic accordingly, so that higher
  828. overall system performance can be achieved.
  829. This feature will have no effect on CPUs without this feature.
  830. If unsure say Y here.
  831. source "kernel/Kconfig.preempt"
  832. config UP_LATE_INIT
  833. def_bool y
  834. depends on !SMP && X86_LOCAL_APIC
  835. config X86_UP_APIC
  836. bool "Local APIC support on uniprocessors" if !PCI_MSI
  837. default PCI_MSI
  838. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  839. ---help---
  840. A local APIC (Advanced Programmable Interrupt Controller) is an
  841. integrated interrupt controller in the CPU. If you have a single-CPU
  842. system which has a processor with a local APIC, you can say Y here to
  843. enable and use it. If you say Y here even though your machine doesn't
  844. have a local APIC, then the kernel will still run with no slowdown at
  845. all. The local APIC supports CPU-generated self-interrupts (timer,
  846. performance counters), and the NMI watchdog which detects hard
  847. lockups.
  848. config X86_UP_IOAPIC
  849. bool "IO-APIC support on uniprocessors"
  850. depends on X86_UP_APIC
  851. ---help---
  852. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  853. SMP-capable replacement for PC-style interrupt controllers. Most
  854. SMP systems and many recent uniprocessor systems have one.
  855. If you have a single-CPU system with an IO-APIC, you can say Y here
  856. to use it. If you say Y here even though your machine doesn't have
  857. an IO-APIC, then the kernel will still run with no slowdown at all.
  858. config X86_LOCAL_APIC
  859. def_bool y
  860. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  861. select IRQ_DOMAIN_HIERARCHY
  862. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  863. config X86_IO_APIC
  864. def_bool y
  865. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  866. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  867. bool "Reroute for broken boot IRQs"
  868. depends on X86_IO_APIC
  869. ---help---
  870. This option enables a workaround that fixes a source of
  871. spurious interrupts. This is recommended when threaded
  872. interrupt handling is used on systems where the generation of
  873. superfluous "boot interrupts" cannot be disabled.
  874. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  875. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  876. kernel does during interrupt handling). On chipsets where this
  877. boot IRQ generation cannot be disabled, this workaround keeps
  878. the original IRQ line masked so that only the equivalent "boot
  879. IRQ" is delivered to the CPUs. The workaround also tells the
  880. kernel to set up the IRQ handler on the boot IRQ line. In this
  881. way only one interrupt is delivered to the kernel. Otherwise
  882. the spurious second interrupt may cause the kernel to bring
  883. down (vital) interrupt lines.
  884. Only affects "broken" chipsets. Interrupt sharing may be
  885. increased on these systems.
  886. config X86_MCE
  887. bool "Machine Check / overheating reporting"
  888. select GENERIC_ALLOCATOR
  889. default y
  890. ---help---
  891. Machine Check support allows the processor to notify the
  892. kernel if it detects a problem (e.g. overheating, data corruption).
  893. The action the kernel takes depends on the severity of the problem,
  894. ranging from warning messages to halting the machine.
  895. config X86_MCE_INTEL
  896. def_bool y
  897. prompt "Intel MCE features"
  898. depends on X86_MCE && X86_LOCAL_APIC
  899. ---help---
  900. Additional support for intel specific MCE features such as
  901. the thermal monitor.
  902. config X86_MCE_AMD
  903. def_bool y
  904. prompt "AMD MCE features"
  905. depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
  906. ---help---
  907. Additional support for AMD specific MCE features such as
  908. the DRAM Error Threshold.
  909. config X86_ANCIENT_MCE
  910. bool "Support for old Pentium 5 / WinChip machine checks"
  911. depends on X86_32 && X86_MCE
  912. ---help---
  913. Include support for machine check handling on old Pentium 5 or WinChip
  914. systems. These typically need to be enabled explicitly on the command
  915. line.
  916. config X86_MCE_THRESHOLD
  917. depends on X86_MCE_AMD || X86_MCE_INTEL
  918. def_bool y
  919. config X86_MCE_INJECT
  920. depends on X86_MCE && X86_LOCAL_APIC
  921. tristate "Machine check injector support"
  922. ---help---
  923. Provide support for injecting machine checks for testing purposes.
  924. If you don't know what a machine check is and you don't do kernel
  925. QA it is safe to say n.
  926. config X86_THERMAL_VECTOR
  927. def_bool y
  928. depends on X86_MCE_INTEL
  929. source "arch/x86/events/Kconfig"
  930. config X86_LEGACY_VM86
  931. bool "Legacy VM86 support"
  932. default n
  933. depends on X86_32
  934. ---help---
  935. This option allows user programs to put the CPU into V8086
  936. mode, which is an 80286-era approximation of 16-bit real mode.
  937. Some very old versions of X and/or vbetool require this option
  938. for user mode setting. Similarly, DOSEMU will use it if
  939. available to accelerate real mode DOS programs. However, any
  940. recent version of DOSEMU, X, or vbetool should be fully
  941. functional even without kernel VM86 support, as they will all
  942. fall back to software emulation. Nevertheless, if you are using
  943. a 16-bit DOS program where 16-bit performance matters, vm86
  944. mode might be faster than emulation and you might want to
  945. enable this option.
  946. Note that any app that works on a 64-bit kernel is unlikely to
  947. need this option, as 64-bit kernels don't, and can't, support
  948. V8086 mode. This option is also unrelated to 16-bit protected
  949. mode and is not needed to run most 16-bit programs under Wine.
  950. Enabling this option increases the complexity of the kernel
  951. and slows down exception handling a tiny bit.
  952. If unsure, say N here.
  953. config VM86
  954. bool
  955. default X86_LEGACY_VM86
  956. config X86_16BIT
  957. bool "Enable support for 16-bit segments" if EXPERT
  958. default y
  959. depends on MODIFY_LDT_SYSCALL
  960. ---help---
  961. This option is required by programs like Wine to run 16-bit
  962. protected mode legacy code on x86 processors. Disabling
  963. this option saves about 300 bytes on i386, or around 6K text
  964. plus 16K runtime memory on x86-64,
  965. config X86_ESPFIX32
  966. def_bool y
  967. depends on X86_16BIT && X86_32
  968. config X86_ESPFIX64
  969. def_bool y
  970. depends on X86_16BIT && X86_64
  971. config X86_VSYSCALL_EMULATION
  972. bool "Enable vsyscall emulation" if EXPERT
  973. default y
  974. depends on X86_64
  975. ---help---
  976. This enables emulation of the legacy vsyscall page. Disabling
  977. it is roughly equivalent to booting with vsyscall=none, except
  978. that it will also disable the helpful warning if a program
  979. tries to use a vsyscall. With this option set to N, offending
  980. programs will just segfault, citing addresses of the form
  981. 0xffffffffff600?00.
  982. This option is required by many programs built before 2013, and
  983. care should be used even with newer programs if set to N.
  984. Disabling this option saves about 7K of kernel size and
  985. possibly 4K of additional runtime pagetable memory.
  986. config TOSHIBA
  987. tristate "Toshiba Laptop support"
  988. depends on X86_32
  989. ---help---
  990. This adds a driver to safely access the System Management Mode of
  991. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  992. not work on models with a Phoenix BIOS. The System Management Mode
  993. is used to set the BIOS and power saving options on Toshiba portables.
  994. For information on utilities to make use of this driver see the
  995. Toshiba Linux utilities web site at:
  996. <http://www.buzzard.org.uk/toshiba/>.
  997. Say Y if you intend to run this kernel on a Toshiba portable.
  998. Say N otherwise.
  999. config I8K
  1000. tristate "Dell i8k legacy laptop support"
  1001. select HWMON
  1002. select SENSORS_DELL_SMM
  1003. ---help---
  1004. This option enables legacy /proc/i8k userspace interface in hwmon
  1005. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  1006. temperature and allows controlling fan speeds of Dell laptops via
  1007. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  1008. it reports also power and hotkey status. For fan speed control is
  1009. needed userspace package i8kutils.
  1010. Say Y if you intend to run this kernel on old Dell laptops or want to
  1011. use userspace package i8kutils.
  1012. Say N otherwise.
  1013. config X86_REBOOTFIXUPS
  1014. bool "Enable X86 board specific fixups for reboot"
  1015. depends on X86_32
  1016. ---help---
  1017. This enables chipset and/or board specific fixups to be done
  1018. in order to get reboot to work correctly. This is only needed on
  1019. some combinations of hardware and BIOS. The symptom, for which
  1020. this config is intended, is when reboot ends with a stalled/hung
  1021. system.
  1022. Currently, the only fixup is for the Geode machines using
  1023. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  1024. Say Y if you want to enable the fixup. Currently, it's safe to
  1025. enable this option even if you don't need it.
  1026. Say N otherwise.
  1027. config MICROCODE
  1028. bool "CPU microcode loading support"
  1029. default y
  1030. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  1031. select FW_LOADER
  1032. ---help---
  1033. If you say Y here, you will be able to update the microcode on
  1034. Intel and AMD processors. The Intel support is for the IA32 family,
  1035. e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
  1036. AMD support is for families 0x10 and later. You will obviously need
  1037. the actual microcode binary data itself which is not shipped with
  1038. the Linux kernel.
  1039. The preferred method to load microcode from a detached initrd is described
  1040. in Documentation/x86/early-microcode.txt. For that you need to enable
  1041. CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
  1042. initrd for microcode blobs.
  1043. In addition, you can build-in the microcode into the kernel. For that you
  1044. need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
  1045. to the CONFIG_EXTRA_FIRMWARE config option.
  1046. config MICROCODE_INTEL
  1047. bool "Intel microcode loading support"
  1048. depends on MICROCODE
  1049. default MICROCODE
  1050. select FW_LOADER
  1051. ---help---
  1052. This options enables microcode patch loading support for Intel
  1053. processors.
  1054. For the current Intel microcode data package go to
  1055. <https://downloadcenter.intel.com> and search for
  1056. 'Linux Processor Microcode Data File'.
  1057. config MICROCODE_AMD
  1058. bool "AMD microcode loading support"
  1059. depends on MICROCODE
  1060. select FW_LOADER
  1061. ---help---
  1062. If you select this option, microcode patch loading support for AMD
  1063. processors will be enabled.
  1064. config MICROCODE_OLD_INTERFACE
  1065. def_bool y
  1066. depends on MICROCODE
  1067. config X86_MSR
  1068. tristate "/dev/cpu/*/msr - Model-specific register support"
  1069. ---help---
  1070. This device gives privileged processes access to the x86
  1071. Model-Specific Registers (MSRs). It is a character device with
  1072. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1073. MSR accesses are directed to a specific CPU on multi-processor
  1074. systems.
  1075. config X86_CPUID
  1076. tristate "/dev/cpu/*/cpuid - CPU information support"
  1077. ---help---
  1078. This device gives processes access to the x86 CPUID instruction to
  1079. be executed on a specific processor. It is a character device
  1080. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1081. /dev/cpu/31/cpuid.
  1082. choice
  1083. prompt "High Memory Support"
  1084. default HIGHMEM4G
  1085. depends on X86_32
  1086. config NOHIGHMEM
  1087. bool "off"
  1088. ---help---
  1089. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1090. However, the address space of 32-bit x86 processors is only 4
  1091. Gigabytes large. That means that, if you have a large amount of
  1092. physical memory, not all of it can be "permanently mapped" by the
  1093. kernel. The physical memory that's not permanently mapped is called
  1094. "high memory".
  1095. If you are compiling a kernel which will never run on a machine with
  1096. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1097. choice and suitable for most users). This will result in a "3GB/1GB"
  1098. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1099. space and the remaining part of the 4GB virtual memory space is used
  1100. by the kernel to permanently map as much physical memory as
  1101. possible.
  1102. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1103. answer "4GB" here.
  1104. If more than 4 Gigabytes is used then answer "64GB" here. This
  1105. selection turns Intel PAE (Physical Address Extension) mode on.
  1106. PAE implements 3-level paging on IA32 processors. PAE is fully
  1107. supported by Linux, PAE mode is implemented on all recent Intel
  1108. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1109. then the kernel will not boot on CPUs that don't support PAE!
  1110. The actual amount of total physical memory will either be
  1111. auto detected or can be forced by using a kernel command line option
  1112. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1113. your boot loader (lilo or loadlin) about how to pass options to the
  1114. kernel at boot time.)
  1115. If unsure, say "off".
  1116. config HIGHMEM4G
  1117. bool "4GB"
  1118. ---help---
  1119. Select this if you have a 32-bit processor and between 1 and 4
  1120. gigabytes of physical RAM.
  1121. config HIGHMEM64G
  1122. bool "64GB"
  1123. depends on !M486
  1124. select X86_PAE
  1125. ---help---
  1126. Select this if you have a 32-bit processor and more than 4
  1127. gigabytes of physical RAM.
  1128. endchoice
  1129. choice
  1130. prompt "Memory split" if EXPERT
  1131. default VMSPLIT_3G
  1132. depends on X86_32
  1133. ---help---
  1134. Select the desired split between kernel and user memory.
  1135. If the address range available to the kernel is less than the
  1136. physical memory installed, the remaining memory will be available
  1137. as "high memory". Accessing high memory is a little more costly
  1138. than low memory, as it needs to be mapped into the kernel first.
  1139. Note that increasing the kernel address space limits the range
  1140. available to user programs, making the address space there
  1141. tighter. Selecting anything other than the default 3G/1G split
  1142. will also likely make your kernel incompatible with binary-only
  1143. kernel modules.
  1144. If you are not absolutely sure what you are doing, leave this
  1145. option alone!
  1146. config VMSPLIT_3G
  1147. bool "3G/1G user/kernel split"
  1148. config VMSPLIT_3G_OPT
  1149. depends on !X86_PAE
  1150. bool "3G/1G user/kernel split (for full 1G low memory)"
  1151. config VMSPLIT_2G
  1152. bool "2G/2G user/kernel split"
  1153. config VMSPLIT_2G_OPT
  1154. depends on !X86_PAE
  1155. bool "2G/2G user/kernel split (for full 2G low memory)"
  1156. config VMSPLIT_1G
  1157. bool "1G/3G user/kernel split"
  1158. endchoice
  1159. config PAGE_OFFSET
  1160. hex
  1161. default 0xB0000000 if VMSPLIT_3G_OPT
  1162. default 0x80000000 if VMSPLIT_2G
  1163. default 0x78000000 if VMSPLIT_2G_OPT
  1164. default 0x40000000 if VMSPLIT_1G
  1165. default 0xC0000000
  1166. depends on X86_32
  1167. config HIGHMEM
  1168. def_bool y
  1169. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1170. config X86_PAE
  1171. bool "PAE (Physical Address Extension) Support"
  1172. depends on X86_32 && !HIGHMEM4G
  1173. select SWIOTLB
  1174. ---help---
  1175. PAE is required for NX support, and furthermore enables
  1176. larger swapspace support for non-overcommit purposes. It
  1177. has the cost of more pagetable lookup overhead, and also
  1178. consumes more pagetable space per process.
  1179. config ARCH_PHYS_ADDR_T_64BIT
  1180. def_bool y
  1181. depends on X86_64 || X86_PAE
  1182. config ARCH_DMA_ADDR_T_64BIT
  1183. def_bool y
  1184. depends on X86_64 || HIGHMEM64G
  1185. config X86_DIRECT_GBPAGES
  1186. def_bool y
  1187. depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
  1188. ---help---
  1189. Certain kernel features effectively disable kernel
  1190. linear 1 GB mappings (even if the CPU otherwise
  1191. supports them), so don't confuse the user by printing
  1192. that we have them enabled.
  1193. # Common NUMA Features
  1194. config NUMA
  1195. bool "Numa Memory Allocation and Scheduler Support"
  1196. depends on SMP
  1197. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1198. default y if X86_BIGSMP
  1199. ---help---
  1200. Enable NUMA (Non Uniform Memory Access) support.
  1201. The kernel will try to allocate memory used by a CPU on the
  1202. local memory controller of the CPU and add some more
  1203. NUMA awareness to the kernel.
  1204. For 64-bit this is recommended if the system is Intel Core i7
  1205. (or later), AMD Opteron, or EM64T NUMA.
  1206. For 32-bit this is only needed if you boot a 32-bit
  1207. kernel on a 64-bit NUMA platform.
  1208. Otherwise, you should say N.
  1209. config AMD_NUMA
  1210. def_bool y
  1211. prompt "Old style AMD Opteron NUMA detection"
  1212. depends on X86_64 && NUMA && PCI
  1213. ---help---
  1214. Enable AMD NUMA node topology detection. You should say Y here if
  1215. you have a multi processor AMD system. This uses an old method to
  1216. read the NUMA configuration directly from the builtin Northbridge
  1217. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1218. which also takes priority if both are compiled in.
  1219. config X86_64_ACPI_NUMA
  1220. def_bool y
  1221. prompt "ACPI NUMA detection"
  1222. depends on X86_64 && NUMA && ACPI && PCI
  1223. select ACPI_NUMA
  1224. ---help---
  1225. Enable ACPI SRAT based node topology detection.
  1226. # Some NUMA nodes have memory ranges that span
  1227. # other nodes. Even though a pfn is valid and
  1228. # between a node's start and end pfns, it may not
  1229. # reside on that node. See memmap_init_zone()
  1230. # for details.
  1231. config NODES_SPAN_OTHER_NODES
  1232. def_bool y
  1233. depends on X86_64_ACPI_NUMA
  1234. config NUMA_EMU
  1235. bool "NUMA emulation"
  1236. depends on NUMA
  1237. ---help---
  1238. Enable NUMA emulation. A flat machine will be split
  1239. into virtual nodes when booted with "numa=fake=N", where N is the
  1240. number of nodes. This is only useful for debugging.
  1241. config NODES_SHIFT
  1242. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1243. range 1 10
  1244. default "10" if MAXSMP
  1245. default "6" if X86_64
  1246. default "3"
  1247. depends on NEED_MULTIPLE_NODES
  1248. ---help---
  1249. Specify the maximum number of NUMA Nodes available on the target
  1250. system. Increases memory reserved to accommodate various tables.
  1251. config ARCH_HAVE_MEMORY_PRESENT
  1252. def_bool y
  1253. depends on X86_32 && DISCONTIGMEM
  1254. config NEED_NODE_MEMMAP_SIZE
  1255. def_bool y
  1256. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1257. config ARCH_FLATMEM_ENABLE
  1258. def_bool y
  1259. depends on X86_32 && !NUMA
  1260. config ARCH_DISCONTIGMEM_ENABLE
  1261. def_bool y
  1262. depends on NUMA && X86_32
  1263. config ARCH_DISCONTIGMEM_DEFAULT
  1264. def_bool y
  1265. depends on NUMA && X86_32
  1266. config ARCH_SPARSEMEM_ENABLE
  1267. def_bool y
  1268. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1269. select SPARSEMEM_STATIC if X86_32
  1270. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1271. config ARCH_SPARSEMEM_DEFAULT
  1272. def_bool y
  1273. depends on X86_64
  1274. config ARCH_SELECT_MEMORY_MODEL
  1275. def_bool y
  1276. depends on ARCH_SPARSEMEM_ENABLE
  1277. config ARCH_MEMORY_PROBE
  1278. bool "Enable sysfs memory/probe interface"
  1279. depends on X86_64 && MEMORY_HOTPLUG
  1280. help
  1281. This option enables a sysfs memory/probe interface for testing.
  1282. See Documentation/memory-hotplug.txt for more information.
  1283. If you are unsure how to answer this question, answer N.
  1284. config ARCH_PROC_KCORE_TEXT
  1285. def_bool y
  1286. depends on X86_64 && PROC_KCORE
  1287. config ILLEGAL_POINTER_VALUE
  1288. hex
  1289. default 0 if X86_32
  1290. default 0xdead000000000000 if X86_64
  1291. source "mm/Kconfig"
  1292. config X86_PMEM_LEGACY_DEVICE
  1293. bool
  1294. config X86_PMEM_LEGACY
  1295. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1296. depends on PHYS_ADDR_T_64BIT
  1297. depends on BLK_DEV
  1298. select X86_PMEM_LEGACY_DEVICE
  1299. select LIBNVDIMM
  1300. help
  1301. Treat memory marked using the non-standard e820 type of 12 as used
  1302. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1303. The kernel will offer these regions to the 'pmem' driver so
  1304. they can be used for persistent storage.
  1305. Say Y if unsure.
  1306. config HIGHPTE
  1307. bool "Allocate 3rd-level pagetables from highmem"
  1308. depends on HIGHMEM
  1309. ---help---
  1310. The VM uses one page table entry for each page of physical memory.
  1311. For systems with a lot of RAM, this can be wasteful of precious
  1312. low memory. Setting this option will put user-space page table
  1313. entries in high memory.
  1314. config X86_CHECK_BIOS_CORRUPTION
  1315. bool "Check for low memory corruption"
  1316. ---help---
  1317. Periodically check for memory corruption in low memory, which
  1318. is suspected to be caused by BIOS. Even when enabled in the
  1319. configuration, it is disabled at runtime. Enable it by
  1320. setting "memory_corruption_check=1" on the kernel command
  1321. line. By default it scans the low 64k of memory every 60
  1322. seconds; see the memory_corruption_check_size and
  1323. memory_corruption_check_period parameters in
  1324. Documentation/admin-guide/kernel-parameters.rst to adjust this.
  1325. When enabled with the default parameters, this option has
  1326. almost no overhead, as it reserves a relatively small amount
  1327. of memory and scans it infrequently. It both detects corruption
  1328. and prevents it from affecting the running system.
  1329. It is, however, intended as a diagnostic tool; if repeatable
  1330. BIOS-originated corruption always affects the same memory,
  1331. you can use memmap= to prevent the kernel from using that
  1332. memory.
  1333. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1334. bool "Set the default setting of memory_corruption_check"
  1335. depends on X86_CHECK_BIOS_CORRUPTION
  1336. default y
  1337. ---help---
  1338. Set whether the default state of memory_corruption_check is
  1339. on or off.
  1340. config X86_RESERVE_LOW
  1341. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1342. default 64
  1343. range 4 640
  1344. ---help---
  1345. Specify the amount of low memory to reserve for the BIOS.
  1346. The first page contains BIOS data structures that the kernel
  1347. must not use, so that page must always be reserved.
  1348. By default we reserve the first 64K of physical RAM, as a
  1349. number of BIOSes are known to corrupt that memory range
  1350. during events such as suspend/resume or monitor cable
  1351. insertion, so it must not be used by the kernel.
  1352. You can set this to 4 if you are absolutely sure that you
  1353. trust the BIOS to get all its memory reservations and usages
  1354. right. If you know your BIOS have problems beyond the
  1355. default 64K area, you can set this to 640 to avoid using the
  1356. entire low memory range.
  1357. If you have doubts about the BIOS (e.g. suspend/resume does
  1358. not work or there's kernel crashes after certain hardware
  1359. hotplug events) then you might want to enable
  1360. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1361. typical corruption patterns.
  1362. Leave this to the default value of 64 if you are unsure.
  1363. config MATH_EMULATION
  1364. bool
  1365. depends on MODIFY_LDT_SYSCALL
  1366. prompt "Math emulation" if X86_32
  1367. ---help---
  1368. Linux can emulate a math coprocessor (used for floating point
  1369. operations) if you don't have one. 486DX and Pentium processors have
  1370. a math coprocessor built in, 486SX and 386 do not, unless you added
  1371. a 487DX or 387, respectively. (The messages during boot time can
  1372. give you some hints here ["man dmesg"].) Everyone needs either a
  1373. coprocessor or this emulation.
  1374. If you don't have a math coprocessor, you need to say Y here; if you
  1375. say Y here even though you have a coprocessor, the coprocessor will
  1376. be used nevertheless. (This behavior can be changed with the kernel
  1377. command line option "no387", which comes handy if your coprocessor
  1378. is broken. Try "man bootparam" or see the documentation of your boot
  1379. loader (lilo or loadlin) about how to pass options to the kernel at
  1380. boot time.) This means that it is a good idea to say Y here if you
  1381. intend to use this kernel on different machines.
  1382. More information about the internals of the Linux math coprocessor
  1383. emulation can be found in <file:arch/x86/math-emu/README>.
  1384. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1385. kernel, it won't hurt.
  1386. config MTRR
  1387. def_bool y
  1388. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1389. ---help---
  1390. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1391. the Memory Type Range Registers (MTRRs) may be used to control
  1392. processor access to memory ranges. This is most useful if you have
  1393. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1394. allows bus write transfers to be combined into a larger transfer
  1395. before bursting over the PCI/AGP bus. This can increase performance
  1396. of image write operations 2.5 times or more. Saying Y here creates a
  1397. /proc/mtrr file which may be used to manipulate your processor's
  1398. MTRRs. Typically the X server should use this.
  1399. This code has a reasonably generic interface so that similar
  1400. control registers on other processors can be easily supported
  1401. as well:
  1402. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1403. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1404. these, the ARRs are used to emulate the MTRRs.
  1405. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1406. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1407. write-combining. All of these processors are supported by this code
  1408. and it makes sense to say Y here if you have one of them.
  1409. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1410. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1411. can lead to all sorts of problems, so it's good to say Y here.
  1412. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1413. just add about 9 KB to your kernel.
  1414. See <file:Documentation/x86/mtrr.txt> for more information.
  1415. config MTRR_SANITIZER
  1416. def_bool y
  1417. prompt "MTRR cleanup support"
  1418. depends on MTRR
  1419. ---help---
  1420. Convert MTRR layout from continuous to discrete, so X drivers can
  1421. add writeback entries.
  1422. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1423. The largest mtrr entry size for a continuous block can be set with
  1424. mtrr_chunk_size.
  1425. If unsure, say Y.
  1426. config MTRR_SANITIZER_ENABLE_DEFAULT
  1427. int "MTRR cleanup enable value (0-1)"
  1428. range 0 1
  1429. default "0"
  1430. depends on MTRR_SANITIZER
  1431. ---help---
  1432. Enable mtrr cleanup default value
  1433. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1434. int "MTRR cleanup spare reg num (0-7)"
  1435. range 0 7
  1436. default "1"
  1437. depends on MTRR_SANITIZER
  1438. ---help---
  1439. mtrr cleanup spare entries default, it can be changed via
  1440. mtrr_spare_reg_nr=N on the kernel command line.
  1441. config X86_PAT
  1442. def_bool y
  1443. prompt "x86 PAT support" if EXPERT
  1444. depends on MTRR
  1445. ---help---
  1446. Use PAT attributes to setup page level cache control.
  1447. PATs are the modern equivalents of MTRRs and are much more
  1448. flexible than MTRRs.
  1449. Say N here if you see bootup problems (boot crash, boot hang,
  1450. spontaneous reboots) or a non-working video driver.
  1451. If unsure, say Y.
  1452. config ARCH_USES_PG_UNCACHED
  1453. def_bool y
  1454. depends on X86_PAT
  1455. config ARCH_RANDOM
  1456. def_bool y
  1457. prompt "x86 architectural random number generator" if EXPERT
  1458. ---help---
  1459. Enable the x86 architectural RDRAND instruction
  1460. (Intel Bull Mountain technology) to generate random numbers.
  1461. If supported, this is a high bandwidth, cryptographically
  1462. secure hardware random number generator.
  1463. config X86_SMAP
  1464. def_bool y
  1465. prompt "Supervisor Mode Access Prevention" if EXPERT
  1466. ---help---
  1467. Supervisor Mode Access Prevention (SMAP) is a security
  1468. feature in newer Intel processors. There is a small
  1469. performance cost if this enabled and turned on; there is
  1470. also a small increase in the kernel size if this is enabled.
  1471. If unsure, say Y.
  1472. config X86_INTEL_MPX
  1473. prompt "Intel MPX (Memory Protection Extensions)"
  1474. def_bool n
  1475. depends on CPU_SUP_INTEL
  1476. ---help---
  1477. MPX provides hardware features that can be used in
  1478. conjunction with compiler-instrumented code to check
  1479. memory references. It is designed to detect buffer
  1480. overflow or underflow bugs.
  1481. This option enables running applications which are
  1482. instrumented or otherwise use MPX. It does not use MPX
  1483. itself inside the kernel or to protect the kernel
  1484. against bad memory references.
  1485. Enabling this option will make the kernel larger:
  1486. ~8k of kernel text and 36 bytes of data on a 64-bit
  1487. defconfig. It adds a long to the 'mm_struct' which
  1488. will increase the kernel memory overhead of each
  1489. process and adds some branches to paths used during
  1490. exec() and munmap().
  1491. For details, see Documentation/x86/intel_mpx.txt
  1492. If unsure, say N.
  1493. config X86_INTEL_MEMORY_PROTECTION_KEYS
  1494. prompt "Intel Memory Protection Keys"
  1495. def_bool y
  1496. # Note: only available in 64-bit mode
  1497. depends on CPU_SUP_INTEL && X86_64
  1498. select ARCH_USES_HIGH_VMA_FLAGS
  1499. select ARCH_HAS_PKEYS
  1500. ---help---
  1501. Memory Protection Keys provides a mechanism for enforcing
  1502. page-based protections, but without requiring modification of the
  1503. page tables when an application changes protection domains.
  1504. For details, see Documentation/x86/protection-keys.txt
  1505. If unsure, say y.
  1506. config EFI
  1507. bool "EFI runtime service support"
  1508. depends on ACPI
  1509. select UCS2_STRING
  1510. select EFI_RUNTIME_WRAPPERS
  1511. ---help---
  1512. This enables the kernel to use EFI runtime services that are
  1513. available (such as the EFI variable services).
  1514. This option is only useful on systems that have EFI firmware.
  1515. In addition, you should use the latest ELILO loader available
  1516. at <http://elilo.sourceforge.net> in order to take advantage
  1517. of EFI runtime services. However, even with this option, the
  1518. resultant kernel should continue to boot on existing non-EFI
  1519. platforms.
  1520. config EFI_STUB
  1521. bool "EFI stub support"
  1522. depends on EFI && !X86_USE_3DNOW
  1523. select RELOCATABLE
  1524. ---help---
  1525. This kernel feature allows a bzImage to be loaded directly
  1526. by EFI firmware without the use of a bootloader.
  1527. See Documentation/efi-stub.txt for more information.
  1528. config EFI_MIXED
  1529. bool "EFI mixed-mode support"
  1530. depends on EFI_STUB && X86_64
  1531. ---help---
  1532. Enabling this feature allows a 64-bit kernel to be booted
  1533. on a 32-bit firmware, provided that your CPU supports 64-bit
  1534. mode.
  1535. Note that it is not possible to boot a mixed-mode enabled
  1536. kernel via the EFI boot stub - a bootloader that supports
  1537. the EFI handover protocol must be used.
  1538. If unsure, say N.
  1539. config SECCOMP
  1540. def_bool y
  1541. prompt "Enable seccomp to safely compute untrusted bytecode"
  1542. ---help---
  1543. This kernel feature is useful for number crunching applications
  1544. that may need to compute untrusted bytecode during their
  1545. execution. By using pipes or other transports made available to
  1546. the process as file descriptors supporting the read/write
  1547. syscalls, it's possible to isolate those applications in
  1548. their own address space using seccomp. Once seccomp is
  1549. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1550. and the task is only allowed to execute a few safe syscalls
  1551. defined by each seccomp mode.
  1552. If unsure, say Y. Only embedded should say N here.
  1553. source kernel/Kconfig.hz
  1554. config KEXEC
  1555. bool "kexec system call"
  1556. select KEXEC_CORE
  1557. ---help---
  1558. kexec is a system call that implements the ability to shutdown your
  1559. current kernel, and to start another kernel. It is like a reboot
  1560. but it is independent of the system firmware. And like a reboot
  1561. you can start any kernel with it, not just Linux.
  1562. The name comes from the similarity to the exec system call.
  1563. It is an ongoing process to be certain the hardware in a machine
  1564. is properly shutdown, so do not be surprised if this code does not
  1565. initially work for you. As of this writing the exact hardware
  1566. interface is strongly in flux, so no good recommendation can be
  1567. made.
  1568. config KEXEC_FILE
  1569. bool "kexec file based system call"
  1570. select KEXEC_CORE
  1571. select BUILD_BIN2C
  1572. depends on X86_64
  1573. depends on CRYPTO=y
  1574. depends on CRYPTO_SHA256=y
  1575. ---help---
  1576. This is new version of kexec system call. This system call is
  1577. file based and takes file descriptors as system call argument
  1578. for kernel and initramfs as opposed to list of segments as
  1579. accepted by previous system call.
  1580. config KEXEC_VERIFY_SIG
  1581. bool "Verify kernel signature during kexec_file_load() syscall"
  1582. depends on KEXEC_FILE
  1583. ---help---
  1584. This option makes kernel signature verification mandatory for
  1585. the kexec_file_load() syscall.
  1586. In addition to that option, you need to enable signature
  1587. verification for the corresponding kernel image type being
  1588. loaded in order for this to work.
  1589. config KEXEC_BZIMAGE_VERIFY_SIG
  1590. bool "Enable bzImage signature verification support"
  1591. depends on KEXEC_VERIFY_SIG
  1592. depends on SIGNED_PE_FILE_VERIFICATION
  1593. select SYSTEM_TRUSTED_KEYRING
  1594. ---help---
  1595. Enable bzImage signature verification support.
  1596. config CRASH_DUMP
  1597. bool "kernel crash dumps"
  1598. depends on X86_64 || (X86_32 && HIGHMEM)
  1599. ---help---
  1600. Generate crash dump after being started by kexec.
  1601. This should be normally only set in special crash dump kernels
  1602. which are loaded in the main kernel with kexec-tools into
  1603. a specially reserved region and then later executed after
  1604. a crash by kdump/kexec. The crash dump kernel must be compiled
  1605. to a memory address not used by the main kernel or BIOS using
  1606. PHYSICAL_START, or it must be built as a relocatable image
  1607. (CONFIG_RELOCATABLE=y).
  1608. For more details see Documentation/kdump/kdump.txt
  1609. config KEXEC_JUMP
  1610. bool "kexec jump"
  1611. depends on KEXEC && HIBERNATION
  1612. ---help---
  1613. Jump between original kernel and kexeced kernel and invoke
  1614. code in physical address mode via KEXEC
  1615. config PHYSICAL_START
  1616. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1617. default "0x1000000"
  1618. ---help---
  1619. This gives the physical address where the kernel is loaded.
  1620. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1621. bzImage will decompress itself to above physical address and
  1622. run from there. Otherwise, bzImage will run from the address where
  1623. it has been loaded by the boot loader and will ignore above physical
  1624. address.
  1625. In normal kdump cases one does not have to set/change this option
  1626. as now bzImage can be compiled as a completely relocatable image
  1627. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1628. address. This option is mainly useful for the folks who don't want
  1629. to use a bzImage for capturing the crash dump and want to use a
  1630. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1631. to be specifically compiled to run from a specific memory area
  1632. (normally a reserved region) and this option comes handy.
  1633. So if you are using bzImage for capturing the crash dump,
  1634. leave the value here unchanged to 0x1000000 and set
  1635. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1636. for capturing the crash dump change this value to start of
  1637. the reserved region. In other words, it can be set based on
  1638. the "X" value as specified in the "crashkernel=YM@XM"
  1639. command line boot parameter passed to the panic-ed
  1640. kernel. Please take a look at Documentation/kdump/kdump.txt
  1641. for more details about crash dumps.
  1642. Usage of bzImage for capturing the crash dump is recommended as
  1643. one does not have to build two kernels. Same kernel can be used
  1644. as production kernel and capture kernel. Above option should have
  1645. gone away after relocatable bzImage support is introduced. But it
  1646. is present because there are users out there who continue to use
  1647. vmlinux for dump capture. This option should go away down the
  1648. line.
  1649. Don't change this unless you know what you are doing.
  1650. config RELOCATABLE
  1651. bool "Build a relocatable kernel"
  1652. default y
  1653. ---help---
  1654. This builds a kernel image that retains relocation information
  1655. so it can be loaded someplace besides the default 1MB.
  1656. The relocations tend to make the kernel binary about 10% larger,
  1657. but are discarded at runtime.
  1658. One use is for the kexec on panic case where the recovery kernel
  1659. must live at a different physical address than the primary
  1660. kernel.
  1661. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1662. it has been loaded at and the compile time physical address
  1663. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1664. config RANDOMIZE_BASE
  1665. bool "Randomize the address of the kernel image (KASLR)"
  1666. depends on RELOCATABLE
  1667. default n
  1668. ---help---
  1669. In support of Kernel Address Space Layout Randomization (KASLR),
  1670. this randomizes the physical address at which the kernel image
  1671. is decompressed and the virtual address where the kernel
  1672. image is mapped, as a security feature that deters exploit
  1673. attempts relying on knowledge of the location of kernel
  1674. code internals.
  1675. On 64-bit, the kernel physical and virtual addresses are
  1676. randomized separately. The physical address will be anywhere
  1677. between 16MB and the top of physical memory (up to 64TB). The
  1678. virtual address will be randomized from 16MB up to 1GB (9 bits
  1679. of entropy). Note that this also reduces the memory space
  1680. available to kernel modules from 1.5GB to 1GB.
  1681. On 32-bit, the kernel physical and virtual addresses are
  1682. randomized together. They will be randomized from 16MB up to
  1683. 512MB (8 bits of entropy).
  1684. Entropy is generated using the RDRAND instruction if it is
  1685. supported. If RDTSC is supported, its value is mixed into
  1686. the entropy pool as well. If neither RDRAND nor RDTSC are
  1687. supported, then entropy is read from the i8254 timer. The
  1688. usable entropy is limited by the kernel being built using
  1689. 2GB addressing, and that PHYSICAL_ALIGN must be at a
  1690. minimum of 2MB. As a result, only 10 bits of entropy are
  1691. theoretically possible, but the implementations are further
  1692. limited due to memory layouts.
  1693. If unsure, say N.
  1694. # Relocation on x86 needs some additional build support
  1695. config X86_NEED_RELOCS
  1696. def_bool y
  1697. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1698. config PHYSICAL_ALIGN
  1699. hex "Alignment value to which kernel should be aligned"
  1700. default "0x200000"
  1701. range 0x2000 0x1000000 if X86_32
  1702. range 0x200000 0x1000000 if X86_64
  1703. ---help---
  1704. This value puts the alignment restrictions on physical address
  1705. where kernel is loaded and run from. Kernel is compiled for an
  1706. address which meets above alignment restriction.
  1707. If bootloader loads the kernel at a non-aligned address and
  1708. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1709. address aligned to above value and run from there.
  1710. If bootloader loads the kernel at a non-aligned address and
  1711. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1712. load address and decompress itself to the address it has been
  1713. compiled for and run from there. The address for which kernel is
  1714. compiled already meets above alignment restrictions. Hence the
  1715. end result is that kernel runs from a physical address meeting
  1716. above alignment restrictions.
  1717. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1718. this value must be a multiple of 0x200000.
  1719. Don't change this unless you know what you are doing.
  1720. config RANDOMIZE_MEMORY
  1721. bool "Randomize the kernel memory sections"
  1722. depends on X86_64
  1723. depends on RANDOMIZE_BASE
  1724. default RANDOMIZE_BASE
  1725. ---help---
  1726. Randomizes the base virtual address of kernel memory sections
  1727. (physical memory mapping, vmalloc & vmemmap). This security feature
  1728. makes exploits relying on predictable memory locations less reliable.
  1729. The order of allocations remains unchanged. Entropy is generated in
  1730. the same way as RANDOMIZE_BASE. Current implementation in the optimal
  1731. configuration have in average 30,000 different possible virtual
  1732. addresses for each memory section.
  1733. If unsure, say N.
  1734. config RANDOMIZE_MEMORY_PHYSICAL_PADDING
  1735. hex "Physical memory mapping padding" if EXPERT
  1736. depends on RANDOMIZE_MEMORY
  1737. default "0xa" if MEMORY_HOTPLUG
  1738. default "0x0"
  1739. range 0x1 0x40 if MEMORY_HOTPLUG
  1740. range 0x0 0x40
  1741. ---help---
  1742. Define the padding in terabytes added to the existing physical
  1743. memory size during kernel memory randomization. It is useful
  1744. for memory hotplug support but reduces the entropy available for
  1745. address randomization.
  1746. If unsure, leave at the default value.
  1747. config HOTPLUG_CPU
  1748. bool "Support for hot-pluggable CPUs"
  1749. depends on SMP
  1750. ---help---
  1751. Say Y here to allow turning CPUs off and on. CPUs can be
  1752. controlled through /sys/devices/system/cpu.
  1753. ( Note: power management support will enable this option
  1754. automatically on SMP systems. )
  1755. Say N if you want to disable CPU hotplug.
  1756. config BOOTPARAM_HOTPLUG_CPU0
  1757. bool "Set default setting of cpu0_hotpluggable"
  1758. default n
  1759. depends on HOTPLUG_CPU
  1760. ---help---
  1761. Set whether default state of cpu0_hotpluggable is on or off.
  1762. Say Y here to enable CPU0 hotplug by default. If this switch
  1763. is turned on, there is no need to give cpu0_hotplug kernel
  1764. parameter and the CPU0 hotplug feature is enabled by default.
  1765. Please note: there are two known CPU0 dependencies if you want
  1766. to enable the CPU0 hotplug feature either by this switch or by
  1767. cpu0_hotplug kernel parameter.
  1768. First, resume from hibernate or suspend always starts from CPU0.
  1769. So hibernate and suspend are prevented if CPU0 is offline.
  1770. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1771. offline if any interrupt can not migrate out of CPU0. There may
  1772. be other CPU0 dependencies.
  1773. Please make sure the dependencies are under your control before
  1774. you enable this feature.
  1775. Say N if you don't want to enable CPU0 hotplug feature by default.
  1776. You still can enable the CPU0 hotplug feature at boot by kernel
  1777. parameter cpu0_hotplug.
  1778. config DEBUG_HOTPLUG_CPU0
  1779. def_bool n
  1780. prompt "Debug CPU0 hotplug"
  1781. depends on HOTPLUG_CPU
  1782. ---help---
  1783. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1784. soon as possible and boots up userspace with CPU0 offlined. User
  1785. can online CPU0 back after boot time.
  1786. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1787. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1788. compilation or giving cpu0_hotplug kernel parameter at boot.
  1789. If unsure, say N.
  1790. config COMPAT_VDSO
  1791. def_bool n
  1792. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1793. depends on COMPAT_32
  1794. ---help---
  1795. Certain buggy versions of glibc will crash if they are
  1796. presented with a 32-bit vDSO that is not mapped at the address
  1797. indicated in its segment table.
  1798. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1799. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1800. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1801. the only released version with the bug, but OpenSUSE 9
  1802. contains a buggy "glibc 2.3.2".
  1803. The symptom of the bug is that everything crashes on startup, saying:
  1804. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1805. Saying Y here changes the default value of the vdso32 boot
  1806. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1807. This works around the glibc bug but hurts performance.
  1808. If unsure, say N: if you are compiling your own kernel, you
  1809. are unlikely to be using a buggy version of glibc.
  1810. choice
  1811. prompt "vsyscall table for legacy applications"
  1812. depends on X86_64
  1813. default LEGACY_VSYSCALL_EMULATE
  1814. help
  1815. Legacy user code that does not know how to find the vDSO expects
  1816. to be able to issue three syscalls by calling fixed addresses in
  1817. kernel space. Since this location is not randomized with ASLR,
  1818. it can be used to assist security vulnerability exploitation.
  1819. This setting can be changed at boot time via the kernel command
  1820. line parameter vsyscall=[native|emulate|none].
  1821. On a system with recent enough glibc (2.14 or newer) and no
  1822. static binaries, you can say None without a performance penalty
  1823. to improve security.
  1824. If unsure, select "Emulate".
  1825. config LEGACY_VSYSCALL_NATIVE
  1826. bool "Native"
  1827. help
  1828. Actual executable code is located in the fixed vsyscall
  1829. address mapping, implementing time() efficiently. Since
  1830. this makes the mapping executable, it can be used during
  1831. security vulnerability exploitation (traditionally as
  1832. ROP gadgets). This configuration is not recommended.
  1833. config LEGACY_VSYSCALL_EMULATE
  1834. bool "Emulate"
  1835. help
  1836. The kernel traps and emulates calls into the fixed
  1837. vsyscall address mapping. This makes the mapping
  1838. non-executable, but it still contains known contents,
  1839. which could be used in certain rare security vulnerability
  1840. exploits. This configuration is recommended when userspace
  1841. still uses the vsyscall area.
  1842. config LEGACY_VSYSCALL_NONE
  1843. bool "None"
  1844. help
  1845. There will be no vsyscall mapping at all. This will
  1846. eliminate any risk of ASLR bypass due to the vsyscall
  1847. fixed address mapping. Attempts to use the vsyscalls
  1848. will be reported to dmesg, so that either old or
  1849. malicious userspace programs can be identified.
  1850. endchoice
  1851. config CMDLINE_BOOL
  1852. bool "Built-in kernel command line"
  1853. ---help---
  1854. Allow for specifying boot arguments to the kernel at
  1855. build time. On some systems (e.g. embedded ones), it is
  1856. necessary or convenient to provide some or all of the
  1857. kernel boot arguments with the kernel itself (that is,
  1858. to not rely on the boot loader to provide them.)
  1859. To compile command line arguments into the kernel,
  1860. set this option to 'Y', then fill in the
  1861. boot arguments in CONFIG_CMDLINE.
  1862. Systems with fully functional boot loaders (i.e. non-embedded)
  1863. should leave this option set to 'N'.
  1864. config CMDLINE
  1865. string "Built-in kernel command string"
  1866. depends on CMDLINE_BOOL
  1867. default ""
  1868. ---help---
  1869. Enter arguments here that should be compiled into the kernel
  1870. image and used at boot time. If the boot loader provides a
  1871. command line at boot time, it is appended to this string to
  1872. form the full kernel command line, when the system boots.
  1873. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1874. change this behavior.
  1875. In most cases, the command line (whether built-in or provided
  1876. by the boot loader) should specify the device for the root
  1877. file system.
  1878. config CMDLINE_OVERRIDE
  1879. bool "Built-in command line overrides boot loader arguments"
  1880. depends on CMDLINE_BOOL
  1881. ---help---
  1882. Set this option to 'Y' to have the kernel ignore the boot loader
  1883. command line, and use ONLY the built-in command line.
  1884. This is used to work around broken boot loaders. This should
  1885. be set to 'N' under normal conditions.
  1886. config MODIFY_LDT_SYSCALL
  1887. bool "Enable the LDT (local descriptor table)" if EXPERT
  1888. default y
  1889. ---help---
  1890. Linux can allow user programs to install a per-process x86
  1891. Local Descriptor Table (LDT) using the modify_ldt(2) system
  1892. call. This is required to run 16-bit or segmented code such as
  1893. DOSEMU or some Wine programs. It is also used by some very old
  1894. threading libraries.
  1895. Enabling this feature adds a small amount of overhead to
  1896. context switches and increases the low-level kernel attack
  1897. surface. Disabling it removes the modify_ldt(2) system call.
  1898. Saying 'N' here may make sense for embedded or server kernels.
  1899. source "kernel/livepatch/Kconfig"
  1900. endmenu
  1901. config ARCH_ENABLE_MEMORY_HOTPLUG
  1902. def_bool y
  1903. depends on X86_64 || (X86_32 && HIGHMEM)
  1904. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1905. def_bool y
  1906. depends on MEMORY_HOTPLUG
  1907. config USE_PERCPU_NUMA_NODE_ID
  1908. def_bool y
  1909. depends on NUMA
  1910. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  1911. def_bool y
  1912. depends on X86_64 || X86_PAE
  1913. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  1914. def_bool y
  1915. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  1916. menu "Power management and ACPI options"
  1917. config ARCH_HIBERNATION_HEADER
  1918. def_bool y
  1919. depends on X86_64 && HIBERNATION
  1920. source "kernel/power/Kconfig"
  1921. source "drivers/acpi/Kconfig"
  1922. source "drivers/sfi/Kconfig"
  1923. config X86_APM_BOOT
  1924. def_bool y
  1925. depends on APM
  1926. menuconfig APM
  1927. tristate "APM (Advanced Power Management) BIOS support"
  1928. depends on X86_32 && PM_SLEEP
  1929. ---help---
  1930. APM is a BIOS specification for saving power using several different
  1931. techniques. This is mostly useful for battery powered laptops with
  1932. APM compliant BIOSes. If you say Y here, the system time will be
  1933. reset after a RESUME operation, the /proc/apm device will provide
  1934. battery status information, and user-space programs will receive
  1935. notification of APM "events" (e.g. battery status change).
  1936. If you select "Y" here, you can disable actual use of the APM
  1937. BIOS by passing the "apm=off" option to the kernel at boot time.
  1938. Note that the APM support is almost completely disabled for
  1939. machines with more than one CPU.
  1940. In order to use APM, you will need supporting software. For location
  1941. and more information, read <file:Documentation/power/apm-acpi.txt>
  1942. and the Battery Powered Linux mini-HOWTO, available from
  1943. <http://www.tldp.org/docs.html#howto>.
  1944. This driver does not spin down disk drives (see the hdparm(8)
  1945. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1946. VESA-compliant "green" monitors.
  1947. This driver does not support the TI 4000M TravelMate and the ACER
  1948. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1949. desktop machines also don't have compliant BIOSes, and this driver
  1950. may cause those machines to panic during the boot phase.
  1951. Generally, if you don't have a battery in your machine, there isn't
  1952. much point in using this driver and you should say N. If you get
  1953. random kernel OOPSes or reboots that don't seem to be related to
  1954. anything, try disabling/enabling this option (or disabling/enabling
  1955. APM in your BIOS).
  1956. Some other things you should try when experiencing seemingly random,
  1957. "weird" problems:
  1958. 1) make sure that you have enough swap space and that it is
  1959. enabled.
  1960. 2) pass the "no-hlt" option to the kernel
  1961. 3) switch on floating point emulation in the kernel and pass
  1962. the "no387" option to the kernel
  1963. 4) pass the "floppy=nodma" option to the kernel
  1964. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1965. all but the first 4 MB of RAM)
  1966. 6) make sure that the CPU is not over clocked.
  1967. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1968. 8) disable the cache from your BIOS settings
  1969. 9) install a fan for the video card or exchange video RAM
  1970. 10) install a better fan for the CPU
  1971. 11) exchange RAM chips
  1972. 12) exchange the motherboard.
  1973. To compile this driver as a module, choose M here: the
  1974. module will be called apm.
  1975. if APM
  1976. config APM_IGNORE_USER_SUSPEND
  1977. bool "Ignore USER SUSPEND"
  1978. ---help---
  1979. This option will ignore USER SUSPEND requests. On machines with a
  1980. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1981. series notebooks, it is necessary to say Y because of a BIOS bug.
  1982. config APM_DO_ENABLE
  1983. bool "Enable PM at boot time"
  1984. ---help---
  1985. Enable APM features at boot time. From page 36 of the APM BIOS
  1986. specification: "When disabled, the APM BIOS does not automatically
  1987. power manage devices, enter the Standby State, enter the Suspend
  1988. State, or take power saving steps in response to CPU Idle calls."
  1989. This driver will make CPU Idle calls when Linux is idle (unless this
  1990. feature is turned off -- see "Do CPU IDLE calls", below). This
  1991. should always save battery power, but more complicated APM features
  1992. will be dependent on your BIOS implementation. You may need to turn
  1993. this option off if your computer hangs at boot time when using APM
  1994. support, or if it beeps continuously instead of suspending. Turn
  1995. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1996. T400CDT. This is off by default since most machines do fine without
  1997. this feature.
  1998. config APM_CPU_IDLE
  1999. depends on CPU_IDLE
  2000. bool "Make CPU Idle calls when idle"
  2001. ---help---
  2002. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  2003. On some machines, this can activate improved power savings, such as
  2004. a slowed CPU clock rate, when the machine is idle. These idle calls
  2005. are made after the idle loop has run for some length of time (e.g.,
  2006. 333 mS). On some machines, this will cause a hang at boot time or
  2007. whenever the CPU becomes idle. (On machines with more than one CPU,
  2008. this option does nothing.)
  2009. config APM_DISPLAY_BLANK
  2010. bool "Enable console blanking using APM"
  2011. ---help---
  2012. Enable console blanking using the APM. Some laptops can use this to
  2013. turn off the LCD backlight when the screen blanker of the Linux
  2014. virtual console blanks the screen. Note that this is only used by
  2015. the virtual console screen blanker, and won't turn off the backlight
  2016. when using the X Window system. This also doesn't have anything to
  2017. do with your VESA-compliant power-saving monitor. Further, this
  2018. option doesn't work for all laptops -- it might not turn off your
  2019. backlight at all, or it might print a lot of errors to the console,
  2020. especially if you are using gpm.
  2021. config APM_ALLOW_INTS
  2022. bool "Allow interrupts during APM BIOS calls"
  2023. ---help---
  2024. Normally we disable external interrupts while we are making calls to
  2025. the APM BIOS as a measure to lessen the effects of a badly behaving
  2026. BIOS implementation. The BIOS should reenable interrupts if it
  2027. needs to. Unfortunately, some BIOSes do not -- especially those in
  2028. many of the newer IBM Thinkpads. If you experience hangs when you
  2029. suspend, try setting this to Y. Otherwise, say N.
  2030. endif # APM
  2031. source "drivers/cpufreq/Kconfig"
  2032. source "drivers/cpuidle/Kconfig"
  2033. source "drivers/idle/Kconfig"
  2034. endmenu
  2035. menu "Bus options (PCI etc.)"
  2036. config PCI
  2037. bool "PCI support"
  2038. default y
  2039. ---help---
  2040. Find out whether you have a PCI motherboard. PCI is the name of a
  2041. bus system, i.e. the way the CPU talks to the other stuff inside
  2042. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  2043. VESA. If you have PCI, say Y, otherwise N.
  2044. choice
  2045. prompt "PCI access mode"
  2046. depends on X86_32 && PCI
  2047. default PCI_GOANY
  2048. ---help---
  2049. On PCI systems, the BIOS can be used to detect the PCI devices and
  2050. determine their configuration. However, some old PCI motherboards
  2051. have BIOS bugs and may crash if this is done. Also, some embedded
  2052. PCI-based systems don't have any BIOS at all. Linux can also try to
  2053. detect the PCI hardware directly without using the BIOS.
  2054. With this option, you can specify how Linux should detect the
  2055. PCI devices. If you choose "BIOS", the BIOS will be used,
  2056. if you choose "Direct", the BIOS won't be used, and if you
  2057. choose "MMConfig", then PCI Express MMCONFIG will be used.
  2058. If you choose "Any", the kernel will try MMCONFIG, then the
  2059. direct access method and falls back to the BIOS if that doesn't
  2060. work. If unsure, go with the default, which is "Any".
  2061. config PCI_GOBIOS
  2062. bool "BIOS"
  2063. config PCI_GOMMCONFIG
  2064. bool "MMConfig"
  2065. config PCI_GODIRECT
  2066. bool "Direct"
  2067. config PCI_GOOLPC
  2068. bool "OLPC XO-1"
  2069. depends on OLPC
  2070. config PCI_GOANY
  2071. bool "Any"
  2072. endchoice
  2073. config PCI_BIOS
  2074. def_bool y
  2075. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  2076. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  2077. config PCI_DIRECT
  2078. def_bool y
  2079. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  2080. config PCI_MMCONFIG
  2081. def_bool y
  2082. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  2083. config PCI_OLPC
  2084. def_bool y
  2085. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  2086. config PCI_XEN
  2087. def_bool y
  2088. depends on PCI && XEN
  2089. select SWIOTLB_XEN
  2090. config PCI_DOMAINS
  2091. def_bool y
  2092. depends on PCI
  2093. config PCI_MMCONFIG
  2094. bool "Support mmconfig PCI config space access"
  2095. depends on X86_64 && PCI && ACPI
  2096. config PCI_CNB20LE_QUIRK
  2097. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  2098. depends on PCI
  2099. help
  2100. Read the PCI windows out of the CNB20LE host bridge. This allows
  2101. PCI hotplug to work on systems with the CNB20LE chipset which do
  2102. not have ACPI.
  2103. There's no public spec for this chipset, and this functionality
  2104. is known to be incomplete.
  2105. You should say N unless you know you need this.
  2106. source "drivers/pci/Kconfig"
  2107. config ISA_BUS
  2108. bool "ISA-style bus support on modern systems" if EXPERT
  2109. select ISA_BUS_API
  2110. help
  2111. Enables ISA-style drivers on modern systems. This is necessary to
  2112. support PC/104 devices on X86_64 platforms.
  2113. If unsure, say N.
  2114. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2115. config ISA_DMA_API
  2116. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2117. default y
  2118. help
  2119. Enables ISA-style DMA support for devices requiring such controllers.
  2120. If unsure, say Y.
  2121. if X86_32
  2122. config ISA
  2123. bool "ISA support"
  2124. ---help---
  2125. Find out whether you have ISA slots on your motherboard. ISA is the
  2126. name of a bus system, i.e. the way the CPU talks to the other stuff
  2127. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2128. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2129. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2130. config EISA
  2131. bool "EISA support"
  2132. depends on ISA
  2133. ---help---
  2134. The Extended Industry Standard Architecture (EISA) bus was
  2135. developed as an open alternative to the IBM MicroChannel bus.
  2136. The EISA bus provided some of the features of the IBM MicroChannel
  2137. bus while maintaining backward compatibility with cards made for
  2138. the older ISA bus. The EISA bus saw limited use between 1988 and
  2139. 1995 when it was made obsolete by the PCI bus.
  2140. Say Y here if you are building a kernel for an EISA-based machine.
  2141. Otherwise, say N.
  2142. source "drivers/eisa/Kconfig"
  2143. config SCx200
  2144. tristate "NatSemi SCx200 support"
  2145. ---help---
  2146. This provides basic support for National Semiconductor's
  2147. (now AMD's) Geode processors. The driver probes for the
  2148. PCI-IDs of several on-chip devices, so its a good dependency
  2149. for other scx200_* drivers.
  2150. If compiled as a module, the driver is named scx200.
  2151. config SCx200HR_TIMER
  2152. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2153. depends on SCx200
  2154. default y
  2155. ---help---
  2156. This driver provides a clocksource built upon the on-chip
  2157. 27MHz high-resolution timer. Its also a workaround for
  2158. NSC Geode SC-1100's buggy TSC, which loses time when the
  2159. processor goes idle (as is done by the scheduler). The
  2160. other workaround is idle=poll boot option.
  2161. config OLPC
  2162. bool "One Laptop Per Child support"
  2163. depends on !X86_PAE
  2164. select GPIOLIB
  2165. select OF
  2166. select OF_PROMTREE
  2167. select IRQ_DOMAIN
  2168. ---help---
  2169. Add support for detecting the unique features of the OLPC
  2170. XO hardware.
  2171. config OLPC_XO1_PM
  2172. bool "OLPC XO-1 Power Management"
  2173. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2174. select MFD_CORE
  2175. ---help---
  2176. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2177. config OLPC_XO1_RTC
  2178. bool "OLPC XO-1 Real Time Clock"
  2179. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2180. ---help---
  2181. Add support for the XO-1 real time clock, which can be used as a
  2182. programmable wakeup source.
  2183. config OLPC_XO1_SCI
  2184. bool "OLPC XO-1 SCI extras"
  2185. depends on OLPC && OLPC_XO1_PM
  2186. depends on INPUT=y
  2187. select POWER_SUPPLY
  2188. select GPIO_CS5535
  2189. select MFD_CORE
  2190. ---help---
  2191. Add support for SCI-based features of the OLPC XO-1 laptop:
  2192. - EC-driven system wakeups
  2193. - Power button
  2194. - Ebook switch
  2195. - Lid switch
  2196. - AC adapter status updates
  2197. - Battery status updates
  2198. config OLPC_XO15_SCI
  2199. bool "OLPC XO-1.5 SCI extras"
  2200. depends on OLPC && ACPI
  2201. select POWER_SUPPLY
  2202. ---help---
  2203. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2204. - EC-driven system wakeups
  2205. - AC adapter status updates
  2206. - Battery status updates
  2207. config ALIX
  2208. bool "PCEngines ALIX System Support (LED setup)"
  2209. select GPIOLIB
  2210. ---help---
  2211. This option enables system support for the PCEngines ALIX.
  2212. At present this just sets up LEDs for GPIO control on
  2213. ALIX2/3/6 boards. However, other system specific setup should
  2214. get added here.
  2215. Note: You must still enable the drivers for GPIO and LED support
  2216. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2217. Note: You have to set alix.force=1 for boards with Award BIOS.
  2218. config NET5501
  2219. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2220. select GPIOLIB
  2221. ---help---
  2222. This option enables system support for the Soekris Engineering net5501.
  2223. config GEOS
  2224. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2225. select GPIOLIB
  2226. depends on DMI
  2227. ---help---
  2228. This option enables system support for the Traverse Technologies GEOS.
  2229. config TS5500
  2230. bool "Technologic Systems TS-5500 platform support"
  2231. depends on MELAN
  2232. select CHECK_SIGNATURE
  2233. select NEW_LEDS
  2234. select LEDS_CLASS
  2235. ---help---
  2236. This option enables system support for the Technologic Systems TS-5500.
  2237. endif # X86_32
  2238. config AMD_NB
  2239. def_bool y
  2240. depends on CPU_SUP_AMD && PCI
  2241. source "drivers/pcmcia/Kconfig"
  2242. config RAPIDIO
  2243. tristate "RapidIO support"
  2244. depends on PCI
  2245. default n
  2246. help
  2247. If enabled this option will include drivers and the core
  2248. infrastructure code to support RapidIO interconnect devices.
  2249. source "drivers/rapidio/Kconfig"
  2250. config X86_SYSFB
  2251. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2252. help
  2253. Firmwares often provide initial graphics framebuffers so the BIOS,
  2254. bootloader or kernel can show basic video-output during boot for
  2255. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2256. Extensions and EFI-framebuffers for this, which are mostly limited
  2257. to x86.
  2258. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2259. framebuffers so the new generic system-framebuffer drivers can be
  2260. used on x86. If the framebuffer is not compatible with the generic
  2261. modes, it is adverticed as fallback platform framebuffer so legacy
  2262. drivers like efifb, vesafb and uvesafb can pick it up.
  2263. If this option is not selected, all system framebuffers are always
  2264. marked as fallback platform framebuffers as usual.
  2265. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2266. not be able to pick up generic system framebuffers if this option
  2267. is selected. You are highly encouraged to enable simplefb as
  2268. replacement if you select this option. simplefb can correctly deal
  2269. with generic system framebuffers. But you should still keep vesafb
  2270. and others enabled as fallback if a system framebuffer is
  2271. incompatible with simplefb.
  2272. If unsure, say Y.
  2273. endmenu
  2274. menu "Executable file formats / Emulations"
  2275. source "fs/Kconfig.binfmt"
  2276. config IA32_EMULATION
  2277. bool "IA32 Emulation"
  2278. depends on X86_64
  2279. select ARCH_WANT_OLD_COMPAT_IPC
  2280. select BINFMT_ELF
  2281. select COMPAT_BINFMT_ELF
  2282. select COMPAT_OLD_SIGACTION
  2283. ---help---
  2284. Include code to run legacy 32-bit programs under a
  2285. 64-bit kernel. You should likely turn this on, unless you're
  2286. 100% sure that you don't have any 32-bit programs left.
  2287. config IA32_AOUT
  2288. tristate "IA32 a.out support"
  2289. depends on IA32_EMULATION
  2290. ---help---
  2291. Support old a.out binaries in the 32bit emulation.
  2292. config X86_X32
  2293. bool "x32 ABI for 64-bit mode"
  2294. depends on X86_64
  2295. ---help---
  2296. Include code to run binaries for the x32 native 32-bit ABI
  2297. for 64-bit processors. An x32 process gets access to the
  2298. full 64-bit register file and wide data path while leaving
  2299. pointers at 32 bits for smaller memory footprint.
  2300. You will need a recent binutils (2.22 or later) with
  2301. elf32_x86_64 support enabled to compile a kernel with this
  2302. option set.
  2303. config COMPAT_32
  2304. def_bool y
  2305. depends on IA32_EMULATION || X86_32
  2306. select HAVE_UID16
  2307. select OLD_SIGSUSPEND3
  2308. config COMPAT
  2309. def_bool y
  2310. depends on IA32_EMULATION || X86_X32
  2311. if COMPAT
  2312. config COMPAT_FOR_U64_ALIGNMENT
  2313. def_bool y
  2314. config SYSVIPC_COMPAT
  2315. def_bool y
  2316. depends on SYSVIPC
  2317. config KEYS_COMPAT
  2318. def_bool y
  2319. depends on KEYS
  2320. endif
  2321. endmenu
  2322. config HAVE_ATOMIC_IOMAP
  2323. def_bool y
  2324. depends on X86_32
  2325. config X86_DEV_DMA_OPS
  2326. bool
  2327. depends on X86_64 || STA2X11
  2328. config X86_DMA_REMAP
  2329. bool
  2330. depends on STA2X11
  2331. source "net/Kconfig"
  2332. source "drivers/Kconfig"
  2333. source "drivers/firmware/Kconfig"
  2334. source "fs/Kconfig"
  2335. source "arch/x86/Kconfig.debug"
  2336. source "security/Kconfig"
  2337. source "crypto/Kconfig"
  2338. source "arch/x86/kvm/Kconfig"
  2339. source "lib/Kconfig"