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_DEVMEM_IS_ALLOWED
  47. select ARCH_HAS_ELF_RANDOMIZE
  48. select ARCH_HAS_FAST_MULTIPLIER
  49. select ARCH_HAS_GCOV_PROFILE_ALL
  50. select ARCH_HAS_KCOV if X86_64
  51. select ARCH_HAS_MMIO_FLUSH
  52. select ARCH_HAS_PMEM_API if X86_64
  53. select ARCH_HAS_SG_CHAIN
  54. select ARCH_HAS_UBSAN_SANITIZE_ALL
  55. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  56. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  57. select ARCH_MIGHT_HAVE_PC_PARPORT
  58. select ARCH_MIGHT_HAVE_PC_SERIO
  59. select ARCH_SUPPORTS_ATOMIC_RMW
  60. select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
  61. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  62. select ARCH_USE_BUILTIN_BSWAP
  63. select ARCH_USE_QUEUED_RWLOCKS
  64. select ARCH_USE_QUEUED_SPINLOCKS
  65. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
  66. select ARCH_WANT_FRAME_POINTERS
  67. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  68. select BUILDTIME_EXTABLE_SORT
  69. select CLKEVT_I8253
  70. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  71. select CLOCKSOURCE_WATCHDOG
  72. select DCACHE_WORD_ACCESS
  73. select EDAC_ATOMIC_SCRUB
  74. select EDAC_SUPPORT
  75. select GENERIC_CLOCKEVENTS
  76. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  77. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  78. select GENERIC_CMOS_UPDATE
  79. select GENERIC_CPU_AUTOPROBE
  80. select GENERIC_EARLY_IOREMAP
  81. select GENERIC_FIND_FIRST_BIT
  82. select GENERIC_IOMAP
  83. select GENERIC_IRQ_PROBE
  84. select GENERIC_IRQ_SHOW
  85. select GENERIC_PENDING_IRQ if SMP
  86. select GENERIC_SMP_IDLE_THREAD
  87. select GENERIC_STRNCPY_FROM_USER
  88. select GENERIC_STRNLEN_USER
  89. select GENERIC_TIME_VSYSCALL
  90. select HAVE_ACPI_APEI if ACPI
  91. select HAVE_ACPI_APEI_NMI if ACPI
  92. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  93. select HAVE_ARCH_AUDITSYSCALL
  94. select HAVE_ARCH_HARDENED_USERCOPY
  95. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  96. select HAVE_ARCH_JUMP_LABEL
  97. select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
  98. select HAVE_ARCH_KGDB
  99. select HAVE_ARCH_KMEMCHECK
  100. select HAVE_ARCH_MMAP_RND_BITS if MMU
  101. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
  102. select HAVE_ARCH_SECCOMP_FILTER
  103. select HAVE_ARCH_TRACEHOOK
  104. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  105. select HAVE_ARCH_VMAP_STACK if X86_64
  106. select HAVE_ARCH_WITHIN_STACK_FRAMES
  107. select HAVE_CC_STACKPROTECTOR
  108. select HAVE_CMPXCHG_DOUBLE
  109. select HAVE_CMPXCHG_LOCAL
  110. select HAVE_CONTEXT_TRACKING if X86_64
  111. select HAVE_COPY_THREAD_TLS
  112. select HAVE_C_RECORDMCOUNT
  113. select HAVE_DEBUG_KMEMLEAK
  114. select HAVE_DEBUG_STACKOVERFLOW
  115. select HAVE_DMA_API_DEBUG
  116. select HAVE_DMA_CONTIGUOUS
  117. select HAVE_DYNAMIC_FTRACE
  118. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  119. select HAVE_EBPF_JIT if X86_64
  120. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  121. select HAVE_EXIT_THREAD
  122. select HAVE_FENTRY if X86_64
  123. select HAVE_FTRACE_MCOUNT_RECORD
  124. select HAVE_FUNCTION_GRAPH_TRACER
  125. select HAVE_FUNCTION_TRACER
  126. select HAVE_GCC_PLUGINS
  127. select HAVE_HW_BREAKPOINT
  128. select HAVE_IDE
  129. select HAVE_IOREMAP_PROT
  130. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  131. select HAVE_IRQ_TIME_ACCOUNTING
  132. select HAVE_KERNEL_BZIP2
  133. select HAVE_KERNEL_GZIP
  134. select HAVE_KERNEL_LZ4
  135. select HAVE_KERNEL_LZMA
  136. select HAVE_KERNEL_LZO
  137. select HAVE_KERNEL_XZ
  138. select HAVE_KPROBES
  139. select HAVE_KPROBES_ON_FTRACE
  140. select HAVE_KRETPROBES
  141. select HAVE_KVM
  142. select HAVE_LIVEPATCH if X86_64
  143. select HAVE_MEMBLOCK
  144. select HAVE_MEMBLOCK_NODE_MAP
  145. select HAVE_MIXED_BREAKPOINTS_REGS
  146. select HAVE_NMI
  147. select HAVE_OPROFILE
  148. select HAVE_OPTPROBES
  149. select HAVE_PCSPKR_PLATFORM
  150. select HAVE_PERF_EVENTS
  151. select HAVE_PERF_EVENTS_NMI
  152. select HAVE_PERF_REGS
  153. select HAVE_PERF_USER_STACK_DUMP
  154. select HAVE_REGS_AND_STACK_ACCESS_API
  155. select HAVE_STACK_VALIDATION if X86_64
  156. select HAVE_SYSCALL_TRACEPOINTS
  157. select HAVE_UNSTABLE_SCHED_CLOCK
  158. select HAVE_USER_RETURN_NOTIFIER
  159. select IRQ_FORCED_THREADING
  160. select PERF_EVENTS
  161. select RTC_LIB
  162. select RTC_MC146818_LIB
  163. select SPARSE_IRQ
  164. select SRCU
  165. select SYSCTL_EXCEPTION_TRACE
  166. select THREAD_INFO_IN_TASK
  167. select USER_STACKTRACE_SUPPORT
  168. select VIRT_TO_BUS
  169. select X86_FEATURE_NAMES if PROC_FS
  170. config INSTRUCTION_DECODER
  171. def_bool y
  172. depends on KPROBES || PERF_EVENTS || UPROBES
  173. config OUTPUT_FORMAT
  174. string
  175. default "elf32-i386" if X86_32
  176. default "elf64-x86-64" if X86_64
  177. config ARCH_DEFCONFIG
  178. string
  179. default "arch/x86/configs/i386_defconfig" if X86_32
  180. default "arch/x86/configs/x86_64_defconfig" if X86_64
  181. config LOCKDEP_SUPPORT
  182. def_bool y
  183. config STACKTRACE_SUPPORT
  184. def_bool y
  185. config MMU
  186. def_bool y
  187. config ARCH_MMAP_RND_BITS_MIN
  188. default 28 if 64BIT
  189. default 8
  190. config ARCH_MMAP_RND_BITS_MAX
  191. default 32 if 64BIT
  192. default 16
  193. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  194. default 8
  195. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  196. default 16
  197. config SBUS
  198. bool
  199. config NEED_DMA_MAP_STATE
  200. def_bool y
  201. depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
  202. config NEED_SG_DMA_LENGTH
  203. def_bool y
  204. config GENERIC_ISA_DMA
  205. def_bool y
  206. depends on ISA_DMA_API
  207. config GENERIC_BUG
  208. def_bool y
  209. depends on BUG
  210. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  211. config GENERIC_BUG_RELATIVE_POINTERS
  212. bool
  213. config GENERIC_HWEIGHT
  214. def_bool y
  215. config ARCH_MAY_HAVE_PC_FDC
  216. def_bool y
  217. depends on ISA_DMA_API
  218. config RWSEM_XCHGADD_ALGORITHM
  219. def_bool y
  220. config GENERIC_CALIBRATE_DELAY
  221. def_bool y
  222. config ARCH_HAS_CPU_RELAX
  223. def_bool y
  224. config ARCH_HAS_CACHE_LINE_SIZE
  225. def_bool y
  226. config HAVE_SETUP_PER_CPU_AREA
  227. def_bool y
  228. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  229. def_bool y
  230. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  231. def_bool y
  232. config ARCH_HIBERNATION_POSSIBLE
  233. def_bool y
  234. config ARCH_SUSPEND_POSSIBLE
  235. def_bool y
  236. config ARCH_WANT_HUGE_PMD_SHARE
  237. def_bool y
  238. config ARCH_WANT_GENERAL_HUGETLB
  239. def_bool y
  240. config ZONE_DMA32
  241. def_bool y if X86_64
  242. config AUDIT_ARCH
  243. def_bool y if X86_64
  244. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  245. def_bool y
  246. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  247. def_bool y
  248. config KASAN_SHADOW_OFFSET
  249. hex
  250. depends on KASAN
  251. default 0xdffffc0000000000
  252. config HAVE_INTEL_TXT
  253. def_bool y
  254. depends on INTEL_IOMMU && ACPI
  255. config X86_32_SMP
  256. def_bool y
  257. depends on X86_32 && SMP
  258. config X86_64_SMP
  259. def_bool y
  260. depends on X86_64 && SMP
  261. config X86_32_LAZY_GS
  262. def_bool y
  263. depends on X86_32 && !CC_STACKPROTECTOR
  264. config ARCH_SUPPORTS_UPROBES
  265. def_bool y
  266. config FIX_EARLYCON_MEM
  267. def_bool y
  268. config DEBUG_RODATA
  269. def_bool y
  270. config PGTABLE_LEVELS
  271. int
  272. default 4 if X86_64
  273. default 3 if X86_PAE
  274. default 2
  275. source "init/Kconfig"
  276. source "kernel/Kconfig.freezer"
  277. menu "Processor type and features"
  278. config ZONE_DMA
  279. bool "DMA memory allocation support" if EXPERT
  280. default y
  281. help
  282. DMA memory allocation support allows devices with less than 32-bit
  283. addressing to allocate within the first 16MB of address space.
  284. Disable if no such devices will be used.
  285. If unsure, say Y.
  286. config SMP
  287. bool "Symmetric multi-processing support"
  288. ---help---
  289. This enables support for systems with more than one CPU. If you have
  290. a system with only one CPU, say N. If you have a system with more
  291. than one CPU, say Y.
  292. If you say N here, the kernel will run on uni- and multiprocessor
  293. machines, but will use only one CPU of a multiprocessor machine. If
  294. you say Y here, the kernel will run on many, but not all,
  295. uniprocessor machines. On a uniprocessor machine, the kernel
  296. will run faster if you say N here.
  297. Note that if you say Y here and choose architecture "586" or
  298. "Pentium" under "Processor family", the kernel will not work on 486
  299. architectures. Similarly, multiprocessor kernels for the "PPro"
  300. architecture may not work on all Pentium based boards.
  301. People using multiprocessor machines who say Y here should also say
  302. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  303. Management" code will be disabled if you say Y here.
  304. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  305. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  306. <http://www.tldp.org/docs.html#howto>.
  307. If you don't know what to do here, say N.
  308. config X86_FEATURE_NAMES
  309. bool "Processor feature human-readable names" if EMBEDDED
  310. default y
  311. ---help---
  312. This option compiles in a table of x86 feature bits and corresponding
  313. names. This is required to support /proc/cpuinfo and a few kernel
  314. messages. You can disable this to save space, at the expense of
  315. making those few kernel messages show numeric feature bits instead.
  316. If in doubt, say Y.
  317. config X86_FAST_FEATURE_TESTS
  318. bool "Fast CPU feature tests" if EMBEDDED
  319. default y
  320. ---help---
  321. Some fast-paths in the kernel depend on the capabilities of the CPU.
  322. Say Y here for the kernel to patch in the appropriate code at runtime
  323. based on the capabilities of the CPU. The infrastructure for patching
  324. code at runtime takes up some additional space; space-constrained
  325. embedded systems may wish to say N here to produce smaller, slightly
  326. slower code.
  327. config X86_X2APIC
  328. bool "Support x2apic"
  329. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  330. ---help---
  331. This enables x2apic support on CPUs that have this feature.
  332. This allows 32-bit apic IDs (so it can support very large systems),
  333. and accesses the local apic via MSRs not via mmio.
  334. If you don't know what to do here, say N.
  335. config X86_MPPARSE
  336. bool "Enable MPS table" if ACPI || SFI
  337. default y
  338. depends on X86_LOCAL_APIC
  339. ---help---
  340. For old smp systems that do not have proper acpi support. Newer systems
  341. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  342. config X86_BIGSMP
  343. bool "Support for big SMP systems with more than 8 CPUs"
  344. depends on X86_32 && SMP
  345. ---help---
  346. This option is needed for the systems that have more than 8 CPUs
  347. config GOLDFISH
  348. def_bool y
  349. depends on X86_GOLDFISH
  350. config INTEL_RDT_A
  351. bool "Intel Resource Director Technology Allocation support"
  352. default n
  353. depends on X86 && CPU_SUP_INTEL
  354. select KERNFS
  355. help
  356. Select to enable resource allocation which is a sub-feature of
  357. Intel Resource Director Technology(RDT). More information about
  358. RDT can be found in the Intel x86 Architecture Software
  359. Developer Manual.
  360. Say N if unsure.
  361. if X86_32
  362. config X86_EXTENDED_PLATFORM
  363. bool "Support for extended (non-PC) x86 platforms"
  364. default y
  365. ---help---
  366. If you disable this option then the kernel will only support
  367. standard PC platforms. (which covers the vast majority of
  368. systems out there.)
  369. If you enable this option then you'll be able to select support
  370. for the following (non-PC) 32 bit x86 platforms:
  371. Goldfish (Android emulator)
  372. AMD Elan
  373. RDC R-321x SoC
  374. SGI 320/540 (Visual Workstation)
  375. STA2X11-based (e.g. Northville)
  376. Moorestown MID devices
  377. If you have one of these systems, or if you want to build a
  378. generic distribution kernel, say Y here - otherwise say N.
  379. endif
  380. if X86_64
  381. config X86_EXTENDED_PLATFORM
  382. bool "Support for extended (non-PC) x86 platforms"
  383. default y
  384. ---help---
  385. If you disable this option then the kernel will only support
  386. standard PC platforms. (which covers the vast majority of
  387. systems out there.)
  388. If you enable this option then you'll be able to select support
  389. for the following (non-PC) 64 bit x86 platforms:
  390. Numascale NumaChip
  391. ScaleMP vSMP
  392. SGI Ultraviolet
  393. If you have one of these systems, or if you want to build a
  394. generic distribution kernel, say Y here - otherwise say N.
  395. endif
  396. # This is an alphabetically sorted list of 64 bit extended platforms
  397. # Please maintain the alphabetic order if and when there are additions
  398. config X86_NUMACHIP
  399. bool "Numascale NumaChip"
  400. depends on X86_64
  401. depends on X86_EXTENDED_PLATFORM
  402. depends on NUMA
  403. depends on SMP
  404. depends on X86_X2APIC
  405. depends on PCI_MMCONFIG
  406. ---help---
  407. Adds support for Numascale NumaChip large-SMP systems. Needed to
  408. enable more than ~168 cores.
  409. If you don't have one of these, you should say N here.
  410. config X86_VSMP
  411. bool "ScaleMP vSMP"
  412. select HYPERVISOR_GUEST
  413. select PARAVIRT
  414. depends on X86_64 && PCI
  415. depends on X86_EXTENDED_PLATFORM
  416. depends on SMP
  417. ---help---
  418. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  419. supposed to run on these EM64T-based machines. Only choose this option
  420. if you have one of these machines.
  421. config X86_UV
  422. bool "SGI Ultraviolet"
  423. depends on X86_64
  424. depends on X86_EXTENDED_PLATFORM
  425. depends on NUMA
  426. depends on EFI
  427. depends on X86_X2APIC
  428. depends on PCI
  429. ---help---
  430. This option is needed in order to support SGI Ultraviolet systems.
  431. If you don't have one of these, you should say N here.
  432. # Following is an alphabetically sorted list of 32 bit extended platforms
  433. # Please maintain the alphabetic order if and when there are additions
  434. config X86_GOLDFISH
  435. bool "Goldfish (Virtual Platform)"
  436. depends on X86_EXTENDED_PLATFORM
  437. ---help---
  438. Enable support for the Goldfish virtual platform used primarily
  439. for Android development. Unless you are building for the Android
  440. Goldfish emulator say N here.
  441. config X86_INTEL_CE
  442. bool "CE4100 TV platform"
  443. depends on PCI
  444. depends on PCI_GODIRECT
  445. depends on X86_IO_APIC
  446. depends on X86_32
  447. depends on X86_EXTENDED_PLATFORM
  448. select X86_REBOOTFIXUPS
  449. select OF
  450. select OF_EARLY_FLATTREE
  451. ---help---
  452. Select for the Intel CE media processor (CE4100) SOC.
  453. This option compiles in support for the CE4100 SOC for settop
  454. boxes and media devices.
  455. config X86_INTEL_MID
  456. bool "Intel MID platform support"
  457. depends on X86_EXTENDED_PLATFORM
  458. depends on X86_PLATFORM_DEVICES
  459. depends on PCI
  460. depends on X86_64 || (PCI_GOANY && X86_32)
  461. depends on X86_IO_APIC
  462. select SFI
  463. select I2C
  464. select DW_APB_TIMER
  465. select APB_TIMER
  466. select INTEL_SCU_IPC
  467. select MFD_INTEL_MSIC
  468. ---help---
  469. Select to build a kernel capable of supporting Intel MID (Mobile
  470. Internet Device) platform systems which do not have the PCI legacy
  471. interfaces. If you are building for a PC class system say N here.
  472. Intel MID platforms are based on an Intel processor and chipset which
  473. consume less power than most of the x86 derivatives.
  474. config X86_INTEL_QUARK
  475. bool "Intel Quark platform support"
  476. depends on X86_32
  477. depends on X86_EXTENDED_PLATFORM
  478. depends on X86_PLATFORM_DEVICES
  479. depends on X86_TSC
  480. depends on PCI
  481. depends on PCI_GOANY
  482. depends on X86_IO_APIC
  483. select IOSF_MBI
  484. select INTEL_IMR
  485. select COMMON_CLK
  486. ---help---
  487. Select to include support for Quark X1000 SoC.
  488. Say Y here if you have a Quark based system such as the Arduino
  489. compatible Intel Galileo.
  490. config X86_INTEL_LPSS
  491. bool "Intel Low Power Subsystem Support"
  492. depends on X86 && ACPI
  493. select COMMON_CLK
  494. select PINCTRL
  495. select IOSF_MBI
  496. ---help---
  497. Select to build support for Intel Low Power Subsystem such as
  498. found on Intel Lynxpoint PCH. Selecting this option enables
  499. things like clock tree (common clock framework) and pincontrol
  500. which are needed by the LPSS peripheral drivers.
  501. config X86_AMD_PLATFORM_DEVICE
  502. bool "AMD ACPI2Platform devices support"
  503. depends on ACPI
  504. select COMMON_CLK
  505. select PINCTRL
  506. ---help---
  507. Select to interpret AMD specific ACPI device to platform device
  508. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  509. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  510. implemented under PINCTRL subsystem.
  511. config IOSF_MBI
  512. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  513. depends on PCI
  514. ---help---
  515. This option enables sideband register access support for Intel SoC
  516. platforms. On these platforms the IOSF sideband is used in lieu of
  517. MSR's for some register accesses, mostly but not limited to thermal
  518. and power. Drivers may query the availability of this device to
  519. determine if they need the sideband in order to work on these
  520. platforms. The sideband is available on the following SoC products.
  521. This list is not meant to be exclusive.
  522. - BayTrail
  523. - Braswell
  524. - Quark
  525. You should say Y if you are running a kernel on one of these SoC's.
  526. config IOSF_MBI_DEBUG
  527. bool "Enable IOSF sideband access through debugfs"
  528. depends on IOSF_MBI && DEBUG_FS
  529. ---help---
  530. Select this option to expose the IOSF sideband access registers (MCR,
  531. MDR, MCRX) through debugfs to write and read register information from
  532. different units on the SoC. This is most useful for obtaining device
  533. state information for debug and analysis. As this is a general access
  534. mechanism, users of this option would have specific knowledge of the
  535. device they want to access.
  536. If you don't require the option or are in doubt, say N.
  537. config X86_RDC321X
  538. bool "RDC R-321x SoC"
  539. depends on X86_32
  540. depends on X86_EXTENDED_PLATFORM
  541. select M486
  542. select X86_REBOOTFIXUPS
  543. ---help---
  544. This option is needed for RDC R-321x system-on-chip, also known
  545. as R-8610-(G).
  546. If you don't have one of these chips, you should say N here.
  547. config X86_32_NON_STANDARD
  548. bool "Support non-standard 32-bit SMP architectures"
  549. depends on X86_32 && SMP
  550. depends on X86_EXTENDED_PLATFORM
  551. ---help---
  552. This option compiles in the bigsmp and STA2X11 default
  553. subarchitectures. It is intended for a generic binary
  554. kernel. If you select them all, kernel will probe it one by
  555. one and will fallback to default.
  556. # Alphabetically sorted list of Non standard 32 bit platforms
  557. config X86_SUPPORTS_MEMORY_FAILURE
  558. def_bool y
  559. # MCE code calls memory_failure():
  560. depends on X86_MCE
  561. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  562. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  563. depends on X86_64 || !SPARSEMEM
  564. select ARCH_SUPPORTS_MEMORY_FAILURE
  565. config STA2X11
  566. bool "STA2X11 Companion Chip Support"
  567. depends on X86_32_NON_STANDARD && PCI
  568. select X86_DEV_DMA_OPS
  569. select X86_DMA_REMAP
  570. select SWIOTLB
  571. select MFD_STA2X11
  572. select GPIOLIB
  573. default n
  574. ---help---
  575. This adds support for boards based on the STA2X11 IO-Hub,
  576. a.k.a. "ConneXt". The chip is used in place of the standard
  577. PC chipset, so all "standard" peripherals are missing. If this
  578. option is selected the kernel will still be able to boot on
  579. standard PC machines.
  580. config X86_32_IRIS
  581. tristate "Eurobraille/Iris poweroff module"
  582. depends on X86_32
  583. ---help---
  584. The Iris machines from EuroBraille do not have APM or ACPI support
  585. to shut themselves down properly. A special I/O sequence is
  586. needed to do so, which is what this module does at
  587. kernel shutdown.
  588. This is only for Iris machines from EuroBraille.
  589. If unused, say N.
  590. config SCHED_OMIT_FRAME_POINTER
  591. def_bool y
  592. prompt "Single-depth WCHAN output"
  593. depends on X86
  594. ---help---
  595. Calculate simpler /proc/<PID>/wchan values. If this option
  596. is disabled then wchan values will recurse back to the
  597. caller function. This provides more accurate wchan values,
  598. at the expense of slightly more scheduling overhead.
  599. If in doubt, say "Y".
  600. menuconfig HYPERVISOR_GUEST
  601. bool "Linux guest support"
  602. ---help---
  603. Say Y here to enable options for running Linux under various hyper-
  604. visors. This option enables basic hypervisor detection and platform
  605. setup.
  606. If you say N, all options in this submenu will be skipped and
  607. disabled, and Linux guest support won't be built in.
  608. if HYPERVISOR_GUEST
  609. config PARAVIRT
  610. bool "Enable paravirtualization code"
  611. ---help---
  612. This changes the kernel so it can modify itself when it is run
  613. under a hypervisor, potentially improving performance significantly
  614. over full virtualization. However, when run without a hypervisor
  615. the kernel is theoretically slower and slightly larger.
  616. config PARAVIRT_DEBUG
  617. bool "paravirt-ops debugging"
  618. depends on PARAVIRT && DEBUG_KERNEL
  619. ---help---
  620. Enable to debug paravirt_ops internals. Specifically, BUG if
  621. a paravirt_op is missing when it is called.
  622. config PARAVIRT_SPINLOCKS
  623. bool "Paravirtualization layer for spinlocks"
  624. depends on PARAVIRT && SMP
  625. ---help---
  626. Paravirtualized spinlocks allow a pvops backend to replace the
  627. spinlock implementation with something virtualization-friendly
  628. (for example, block the virtual CPU rather than spinning).
  629. It has a minimal impact on native kernels and gives a nice performance
  630. benefit on paravirtualized KVM / Xen kernels.
  631. If you are unsure how to answer this question, answer Y.
  632. config QUEUED_LOCK_STAT
  633. bool "Paravirt queued spinlock statistics"
  634. depends on PARAVIRT_SPINLOCKS && DEBUG_FS
  635. ---help---
  636. Enable the collection of statistical data on the slowpath
  637. behavior of paravirtualized queued spinlocks and report
  638. them on debugfs.
  639. source "arch/x86/xen/Kconfig"
  640. config KVM_GUEST
  641. bool "KVM Guest support (including kvmclock)"
  642. depends on PARAVIRT
  643. select PARAVIRT_CLOCK
  644. default y
  645. ---help---
  646. This option enables various optimizations for running under the KVM
  647. hypervisor. It includes a paravirtualized clock, so that instead
  648. of relying on a PIT (or probably other) emulation by the
  649. underlying device model, the host provides the guest with
  650. timing infrastructure such as time of day, and system time
  651. config KVM_DEBUG_FS
  652. bool "Enable debug information for KVM Guests in debugfs"
  653. depends on KVM_GUEST && DEBUG_FS
  654. default n
  655. ---help---
  656. This option enables collection of various statistics for KVM guest.
  657. Statistics are displayed in debugfs filesystem. Enabling this option
  658. may incur significant overhead.
  659. source "arch/x86/lguest/Kconfig"
  660. config PARAVIRT_TIME_ACCOUNTING
  661. bool "Paravirtual steal time accounting"
  662. depends on PARAVIRT
  663. default n
  664. ---help---
  665. Select this option to enable fine granularity task steal time
  666. accounting. Time spent executing other tasks in parallel with
  667. the current vCPU is discounted from the vCPU power. To account for
  668. that, there can be a small performance impact.
  669. If in doubt, say N here.
  670. config PARAVIRT_CLOCK
  671. bool
  672. endif #HYPERVISOR_GUEST
  673. config NO_BOOTMEM
  674. def_bool y
  675. source "arch/x86/Kconfig.cpu"
  676. config HPET_TIMER
  677. def_bool X86_64
  678. prompt "HPET Timer Support" if X86_32
  679. ---help---
  680. Use the IA-PC HPET (High Precision Event Timer) to manage
  681. time in preference to the PIT and RTC, if a HPET is
  682. present.
  683. HPET is the next generation timer replacing legacy 8254s.
  684. The HPET provides a stable time base on SMP
  685. systems, unlike the TSC, but it is more expensive to access,
  686. as it is off-chip. The interface used is documented
  687. in the HPET spec, revision 1.
  688. You can safely choose Y here. However, HPET will only be
  689. activated if the platform and the BIOS support this feature.
  690. Otherwise the 8254 will be used for timing services.
  691. Choose N to continue using the legacy 8254 timer.
  692. config HPET_EMULATE_RTC
  693. def_bool y
  694. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  695. config APB_TIMER
  696. def_bool y if X86_INTEL_MID
  697. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  698. select DW_APB_TIMER
  699. depends on X86_INTEL_MID && SFI
  700. help
  701. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  702. The APBT provides a stable time base on SMP
  703. systems, unlike the TSC, but it is more expensive to access,
  704. as it is off-chip. APB timers are always running regardless of CPU
  705. C states, they are used as per CPU clockevent device when possible.
  706. # Mark as expert because too many people got it wrong.
  707. # The code disables itself when not needed.
  708. config DMI
  709. default y
  710. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  711. bool "Enable DMI scanning" if EXPERT
  712. ---help---
  713. Enabled scanning of DMI to identify machine quirks. Say Y
  714. here unless you have verified that your setup is not
  715. affected by entries in the DMI blacklist. Required by PNP
  716. BIOS code.
  717. config GART_IOMMU
  718. bool "Old AMD GART IOMMU support"
  719. select SWIOTLB
  720. depends on X86_64 && PCI && AMD_NB
  721. ---help---
  722. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  723. GART based hardware IOMMUs.
  724. The GART supports full DMA access for devices with 32-bit access
  725. limitations, on systems with more than 3 GB. This is usually needed
  726. for USB, sound, many IDE/SATA chipsets and some other devices.
  727. Newer systems typically have a modern AMD IOMMU, supported via
  728. the CONFIG_AMD_IOMMU=y config option.
  729. In normal configurations this driver is only active when needed:
  730. there's more than 3 GB of memory and the system contains a
  731. 32-bit limited device.
  732. If unsure, say Y.
  733. config CALGARY_IOMMU
  734. bool "IBM Calgary IOMMU support"
  735. select SWIOTLB
  736. depends on X86_64 && PCI
  737. ---help---
  738. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  739. systems. Needed to run systems with more than 3GB of memory
  740. properly with 32-bit PCI devices that do not support DAC
  741. (Double Address Cycle). Calgary also supports bus level
  742. isolation, where all DMAs pass through the IOMMU. This
  743. prevents them from going anywhere except their intended
  744. destination. This catches hard-to-find kernel bugs and
  745. mis-behaving drivers and devices that do not use the DMA-API
  746. properly to set up their DMA buffers. The IOMMU can be
  747. turned off at boot time with the iommu=off parameter.
  748. Normally the kernel will make the right choice by itself.
  749. If unsure, say Y.
  750. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  751. def_bool y
  752. prompt "Should Calgary be enabled by default?"
  753. depends on CALGARY_IOMMU
  754. ---help---
  755. Should Calgary be enabled by default? if you choose 'y', Calgary
  756. will be used (if it exists). If you choose 'n', Calgary will not be
  757. used even if it exists. If you choose 'n' and would like to use
  758. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  759. If unsure, say Y.
  760. # need this always selected by IOMMU for the VIA workaround
  761. config SWIOTLB
  762. def_bool y if X86_64
  763. ---help---
  764. Support for software bounce buffers used on x86-64 systems
  765. which don't have a hardware IOMMU. Using this PCI devices
  766. which can only access 32-bits of memory can be used on systems
  767. with more than 3 GB of memory.
  768. If unsure, say Y.
  769. config IOMMU_HELPER
  770. def_bool y
  771. depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
  772. config MAXSMP
  773. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  774. depends on X86_64 && SMP && DEBUG_KERNEL
  775. select CPUMASK_OFFSTACK
  776. ---help---
  777. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  778. If unsure, say N.
  779. config NR_CPUS
  780. int "Maximum number of CPUs" if SMP && !MAXSMP
  781. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  782. range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
  783. range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
  784. default "1" if !SMP
  785. default "8192" if MAXSMP
  786. default "32" if SMP && X86_BIGSMP
  787. default "8" if SMP && X86_32
  788. default "64" if SMP
  789. ---help---
  790. This allows you to specify the maximum number of CPUs which this
  791. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  792. supported value is 8192, otherwise the maximum value is 512. The
  793. minimum value which makes sense is 2.
  794. This is purely to save memory - each supported CPU adds
  795. approximately eight kilobytes to the kernel image.
  796. config SCHED_SMT
  797. bool "SMT (Hyperthreading) scheduler support"
  798. depends on SMP
  799. ---help---
  800. SMT scheduler support improves the CPU scheduler's decision making
  801. when dealing with Intel Pentium 4 chips with HyperThreading at a
  802. cost of slightly increased overhead in some places. If unsure say
  803. N here.
  804. config SCHED_MC
  805. def_bool y
  806. prompt "Multi-core scheduler support"
  807. depends on SMP
  808. ---help---
  809. Multi-core scheduler support improves the CPU scheduler's decision
  810. making when dealing with multi-core CPU chips at a cost of slightly
  811. increased overhead in some places. If unsure say N here.
  812. config SCHED_MC_PRIO
  813. bool "CPU core priorities scheduler support"
  814. depends on SCHED_MC && CPU_SUP_INTEL
  815. select X86_INTEL_PSTATE
  816. select CPU_FREQ
  817. default y
  818. ---help---
  819. Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
  820. core ordering determined at manufacturing time, which allows
  821. certain cores to reach higher turbo frequencies (when running
  822. single threaded workloads) than others.
  823. Enabling this kernel feature teaches the scheduler about
  824. the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
  825. scheduler's CPU selection logic accordingly, so that higher
  826. overall system performance can be achieved.
  827. This feature will have no effect on CPUs without this feature.
  828. If unsure say Y here.
  829. source "kernel/Kconfig.preempt"
  830. config UP_LATE_INIT
  831. def_bool y
  832. depends on !SMP && X86_LOCAL_APIC
  833. config X86_UP_APIC
  834. bool "Local APIC support on uniprocessors" if !PCI_MSI
  835. default PCI_MSI
  836. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  837. ---help---
  838. A local APIC (Advanced Programmable Interrupt Controller) is an
  839. integrated interrupt controller in the CPU. If you have a single-CPU
  840. system which has a processor with a local APIC, you can say Y here to
  841. enable and use it. If you say Y here even though your machine doesn't
  842. have a local APIC, then the kernel will still run with no slowdown at
  843. all. The local APIC supports CPU-generated self-interrupts (timer,
  844. performance counters), and the NMI watchdog which detects hard
  845. lockups.
  846. config X86_UP_IOAPIC
  847. bool "IO-APIC support on uniprocessors"
  848. depends on X86_UP_APIC
  849. ---help---
  850. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  851. SMP-capable replacement for PC-style interrupt controllers. Most
  852. SMP systems and many recent uniprocessor systems have one.
  853. If you have a single-CPU system with an IO-APIC, you can say Y here
  854. to use it. If you say Y here even though your machine doesn't have
  855. an IO-APIC, then the kernel will still run with no slowdown at all.
  856. config X86_LOCAL_APIC
  857. def_bool y
  858. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  859. select IRQ_DOMAIN_HIERARCHY
  860. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  861. config X86_IO_APIC
  862. def_bool y
  863. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  864. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  865. bool "Reroute for broken boot IRQs"
  866. depends on X86_IO_APIC
  867. ---help---
  868. This option enables a workaround that fixes a source of
  869. spurious interrupts. This is recommended when threaded
  870. interrupt handling is used on systems where the generation of
  871. superfluous "boot interrupts" cannot be disabled.
  872. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  873. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  874. kernel does during interrupt handling). On chipsets where this
  875. boot IRQ generation cannot be disabled, this workaround keeps
  876. the original IRQ line masked so that only the equivalent "boot
  877. IRQ" is delivered to the CPUs. The workaround also tells the
  878. kernel to set up the IRQ handler on the boot IRQ line. In this
  879. way only one interrupt is delivered to the kernel. Otherwise
  880. the spurious second interrupt may cause the kernel to bring
  881. down (vital) interrupt lines.
  882. Only affects "broken" chipsets. Interrupt sharing may be
  883. increased on these systems.
  884. config X86_MCE
  885. bool "Machine Check / overheating reporting"
  886. select GENERIC_ALLOCATOR
  887. default y
  888. ---help---
  889. Machine Check support allows the processor to notify the
  890. kernel if it detects a problem (e.g. overheating, data corruption).
  891. The action the kernel takes depends on the severity of the problem,
  892. ranging from warning messages to halting the machine.
  893. config X86_MCE_INTEL
  894. def_bool y
  895. prompt "Intel MCE features"
  896. depends on X86_MCE && X86_LOCAL_APIC
  897. ---help---
  898. Additional support for intel specific MCE features such as
  899. the thermal monitor.
  900. config X86_MCE_AMD
  901. def_bool y
  902. prompt "AMD MCE features"
  903. depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
  904. ---help---
  905. Additional support for AMD specific MCE features such as
  906. the DRAM Error Threshold.
  907. config X86_ANCIENT_MCE
  908. bool "Support for old Pentium 5 / WinChip machine checks"
  909. depends on X86_32 && X86_MCE
  910. ---help---
  911. Include support for machine check handling on old Pentium 5 or WinChip
  912. systems. These typically need to be enabled explicitly on the command
  913. line.
  914. config X86_MCE_THRESHOLD
  915. depends on X86_MCE_AMD || X86_MCE_INTEL
  916. def_bool y
  917. config X86_MCE_INJECT
  918. depends on X86_MCE
  919. tristate "Machine check injector support"
  920. ---help---
  921. Provide support for injecting machine checks for testing purposes.
  922. If you don't know what a machine check is and you don't do kernel
  923. QA it is safe to say n.
  924. config X86_THERMAL_VECTOR
  925. def_bool y
  926. depends on X86_MCE_INTEL
  927. source "arch/x86/events/Kconfig"
  928. config X86_LEGACY_VM86
  929. bool "Legacy VM86 support"
  930. default n
  931. depends on X86_32
  932. ---help---
  933. This option allows user programs to put the CPU into V8086
  934. mode, which is an 80286-era approximation of 16-bit real mode.
  935. Some very old versions of X and/or vbetool require this option
  936. for user mode setting. Similarly, DOSEMU will use it if
  937. available to accelerate real mode DOS programs. However, any
  938. recent version of DOSEMU, X, or vbetool should be fully
  939. functional even without kernel VM86 support, as they will all
  940. fall back to software emulation. Nevertheless, if you are using
  941. a 16-bit DOS program where 16-bit performance matters, vm86
  942. mode might be faster than emulation and you might want to
  943. enable this option.
  944. Note that any app that works on a 64-bit kernel is unlikely to
  945. need this option, as 64-bit kernels don't, and can't, support
  946. V8086 mode. This option is also unrelated to 16-bit protected
  947. mode and is not needed to run most 16-bit programs under Wine.
  948. Enabling this option increases the complexity of the kernel
  949. and slows down exception handling a tiny bit.
  950. If unsure, say N here.
  951. config VM86
  952. bool
  953. default X86_LEGACY_VM86
  954. config X86_16BIT
  955. bool "Enable support for 16-bit segments" if EXPERT
  956. default y
  957. depends on MODIFY_LDT_SYSCALL
  958. ---help---
  959. This option is required by programs like Wine to run 16-bit
  960. protected mode legacy code on x86 processors. Disabling
  961. this option saves about 300 bytes on i386, or around 6K text
  962. plus 16K runtime memory on x86-64,
  963. config X86_ESPFIX32
  964. def_bool y
  965. depends on X86_16BIT && X86_32
  966. config X86_ESPFIX64
  967. def_bool y
  968. depends on X86_16BIT && X86_64
  969. config X86_VSYSCALL_EMULATION
  970. bool "Enable vsyscall emulation" if EXPERT
  971. default y
  972. depends on X86_64
  973. ---help---
  974. This enables emulation of the legacy vsyscall page. Disabling
  975. it is roughly equivalent to booting with vsyscall=none, except
  976. that it will also disable the helpful warning if a program
  977. tries to use a vsyscall. With this option set to N, offending
  978. programs will just segfault, citing addresses of the form
  979. 0xffffffffff600?00.
  980. This option is required by many programs built before 2013, and
  981. care should be used even with newer programs if set to N.
  982. Disabling this option saves about 7K of kernel size and
  983. possibly 4K of additional runtime pagetable memory.
  984. config TOSHIBA
  985. tristate "Toshiba Laptop support"
  986. depends on X86_32
  987. ---help---
  988. This adds a driver to safely access the System Management Mode of
  989. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  990. not work on models with a Phoenix BIOS. The System Management Mode
  991. is used to set the BIOS and power saving options on Toshiba portables.
  992. For information on utilities to make use of this driver see the
  993. Toshiba Linux utilities web site at:
  994. <http://www.buzzard.org.uk/toshiba/>.
  995. Say Y if you intend to run this kernel on a Toshiba portable.
  996. Say N otherwise.
  997. config I8K
  998. tristate "Dell i8k legacy laptop support"
  999. select HWMON
  1000. select SENSORS_DELL_SMM
  1001. ---help---
  1002. This option enables legacy /proc/i8k userspace interface in hwmon
  1003. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  1004. temperature and allows controlling fan speeds of Dell laptops via
  1005. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  1006. it reports also power and hotkey status. For fan speed control is
  1007. needed userspace package i8kutils.
  1008. Say Y if you intend to run this kernel on old Dell laptops or want to
  1009. use userspace package i8kutils.
  1010. Say N otherwise.
  1011. config X86_REBOOTFIXUPS
  1012. bool "Enable X86 board specific fixups for reboot"
  1013. depends on X86_32
  1014. ---help---
  1015. This enables chipset and/or board specific fixups to be done
  1016. in order to get reboot to work correctly. This is only needed on
  1017. some combinations of hardware and BIOS. The symptom, for which
  1018. this config is intended, is when reboot ends with a stalled/hung
  1019. system.
  1020. Currently, the only fixup is for the Geode machines using
  1021. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  1022. Say Y if you want to enable the fixup. Currently, it's safe to
  1023. enable this option even if you don't need it.
  1024. Say N otherwise.
  1025. config MICROCODE
  1026. bool "CPU microcode loading support"
  1027. default y
  1028. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  1029. select FW_LOADER
  1030. ---help---
  1031. If you say Y here, you will be able to update the microcode on
  1032. Intel and AMD processors. The Intel support is for the IA32 family,
  1033. e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
  1034. AMD support is for families 0x10 and later. You will obviously need
  1035. the actual microcode binary data itself which is not shipped with
  1036. the Linux kernel.
  1037. The preferred method to load microcode from a detached initrd is described
  1038. in Documentation/x86/early-microcode.txt. For that you need to enable
  1039. CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
  1040. initrd for microcode blobs.
  1041. In addition, you can build-in the microcode into the kernel. For that you
  1042. need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
  1043. to the CONFIG_EXTRA_FIRMWARE config option.
  1044. config MICROCODE_INTEL
  1045. bool "Intel microcode loading support"
  1046. depends on MICROCODE
  1047. default MICROCODE
  1048. select FW_LOADER
  1049. ---help---
  1050. This options enables microcode patch loading support for Intel
  1051. processors.
  1052. For the current Intel microcode data package go to
  1053. <https://downloadcenter.intel.com> and search for
  1054. 'Linux Processor Microcode Data File'.
  1055. config MICROCODE_AMD
  1056. bool "AMD microcode loading support"
  1057. depends on MICROCODE
  1058. select FW_LOADER
  1059. ---help---
  1060. If you select this option, microcode patch loading support for AMD
  1061. processors will be enabled.
  1062. config MICROCODE_OLD_INTERFACE
  1063. def_bool y
  1064. depends on MICROCODE
  1065. config X86_MSR
  1066. tristate "/dev/cpu/*/msr - Model-specific register support"
  1067. ---help---
  1068. This device gives privileged processes access to the x86
  1069. Model-Specific Registers (MSRs). It is a character device with
  1070. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1071. MSR accesses are directed to a specific CPU on multi-processor
  1072. systems.
  1073. config X86_CPUID
  1074. tristate "/dev/cpu/*/cpuid - CPU information support"
  1075. ---help---
  1076. This device gives processes access to the x86 CPUID instruction to
  1077. be executed on a specific processor. It is a character device
  1078. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1079. /dev/cpu/31/cpuid.
  1080. choice
  1081. prompt "High Memory Support"
  1082. default HIGHMEM4G
  1083. depends on X86_32
  1084. config NOHIGHMEM
  1085. bool "off"
  1086. ---help---
  1087. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1088. However, the address space of 32-bit x86 processors is only 4
  1089. Gigabytes large. That means that, if you have a large amount of
  1090. physical memory, not all of it can be "permanently mapped" by the
  1091. kernel. The physical memory that's not permanently mapped is called
  1092. "high memory".
  1093. If you are compiling a kernel which will never run on a machine with
  1094. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1095. choice and suitable for most users). This will result in a "3GB/1GB"
  1096. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1097. space and the remaining part of the 4GB virtual memory space is used
  1098. by the kernel to permanently map as much physical memory as
  1099. possible.
  1100. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1101. answer "4GB" here.
  1102. If more than 4 Gigabytes is used then answer "64GB" here. This
  1103. selection turns Intel PAE (Physical Address Extension) mode on.
  1104. PAE implements 3-level paging on IA32 processors. PAE is fully
  1105. supported by Linux, PAE mode is implemented on all recent Intel
  1106. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1107. then the kernel will not boot on CPUs that don't support PAE!
  1108. The actual amount of total physical memory will either be
  1109. auto detected or can be forced by using a kernel command line option
  1110. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1111. your boot loader (lilo or loadlin) about how to pass options to the
  1112. kernel at boot time.)
  1113. If unsure, say "off".
  1114. config HIGHMEM4G
  1115. bool "4GB"
  1116. ---help---
  1117. Select this if you have a 32-bit processor and between 1 and 4
  1118. gigabytes of physical RAM.
  1119. config HIGHMEM64G
  1120. bool "64GB"
  1121. depends on !M486
  1122. select X86_PAE
  1123. ---help---
  1124. Select this if you have a 32-bit processor and more than 4
  1125. gigabytes of physical RAM.
  1126. endchoice
  1127. choice
  1128. prompt "Memory split" if EXPERT
  1129. default VMSPLIT_3G
  1130. depends on X86_32
  1131. ---help---
  1132. Select the desired split between kernel and user memory.
  1133. If the address range available to the kernel is less than the
  1134. physical memory installed, the remaining memory will be available
  1135. as "high memory". Accessing high memory is a little more costly
  1136. than low memory, as it needs to be mapped into the kernel first.
  1137. Note that increasing the kernel address space limits the range
  1138. available to user programs, making the address space there
  1139. tighter. Selecting anything other than the default 3G/1G split
  1140. will also likely make your kernel incompatible with binary-only
  1141. kernel modules.
  1142. If you are not absolutely sure what you are doing, leave this
  1143. option alone!
  1144. config VMSPLIT_3G
  1145. bool "3G/1G user/kernel split"
  1146. config VMSPLIT_3G_OPT
  1147. depends on !X86_PAE
  1148. bool "3G/1G user/kernel split (for full 1G low memory)"
  1149. config VMSPLIT_2G
  1150. bool "2G/2G user/kernel split"
  1151. config VMSPLIT_2G_OPT
  1152. depends on !X86_PAE
  1153. bool "2G/2G user/kernel split (for full 2G low memory)"
  1154. config VMSPLIT_1G
  1155. bool "1G/3G user/kernel split"
  1156. endchoice
  1157. config PAGE_OFFSET
  1158. hex
  1159. default 0xB0000000 if VMSPLIT_3G_OPT
  1160. default 0x80000000 if VMSPLIT_2G
  1161. default 0x78000000 if VMSPLIT_2G_OPT
  1162. default 0x40000000 if VMSPLIT_1G
  1163. default 0xC0000000
  1164. depends on X86_32
  1165. config HIGHMEM
  1166. def_bool y
  1167. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1168. config X86_PAE
  1169. bool "PAE (Physical Address Extension) Support"
  1170. depends on X86_32 && !HIGHMEM4G
  1171. select SWIOTLB
  1172. ---help---
  1173. PAE is required for NX support, and furthermore enables
  1174. larger swapspace support for non-overcommit purposes. It
  1175. has the cost of more pagetable lookup overhead, and also
  1176. consumes more pagetable space per process.
  1177. config ARCH_PHYS_ADDR_T_64BIT
  1178. def_bool y
  1179. depends on X86_64 || X86_PAE
  1180. config ARCH_DMA_ADDR_T_64BIT
  1181. def_bool y
  1182. depends on X86_64 || HIGHMEM64G
  1183. config X86_DIRECT_GBPAGES
  1184. def_bool y
  1185. depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
  1186. ---help---
  1187. Certain kernel features effectively disable kernel
  1188. linear 1 GB mappings (even if the CPU otherwise
  1189. supports them), so don't confuse the user by printing
  1190. that we have them enabled.
  1191. # Common NUMA Features
  1192. config NUMA
  1193. bool "Numa Memory Allocation and Scheduler Support"
  1194. depends on SMP
  1195. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1196. default y if X86_BIGSMP
  1197. ---help---
  1198. Enable NUMA (Non Uniform Memory Access) support.
  1199. The kernel will try to allocate memory used by a CPU on the
  1200. local memory controller of the CPU and add some more
  1201. NUMA awareness to the kernel.
  1202. For 64-bit this is recommended if the system is Intel Core i7
  1203. (or later), AMD Opteron, or EM64T NUMA.
  1204. For 32-bit this is only needed if you boot a 32-bit
  1205. kernel on a 64-bit NUMA platform.
  1206. Otherwise, you should say N.
  1207. config AMD_NUMA
  1208. def_bool y
  1209. prompt "Old style AMD Opteron NUMA detection"
  1210. depends on X86_64 && NUMA && PCI
  1211. ---help---
  1212. Enable AMD NUMA node topology detection. You should say Y here if
  1213. you have a multi processor AMD system. This uses an old method to
  1214. read the NUMA configuration directly from the builtin Northbridge
  1215. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1216. which also takes priority if both are compiled in.
  1217. config X86_64_ACPI_NUMA
  1218. def_bool y
  1219. prompt "ACPI NUMA detection"
  1220. depends on X86_64 && NUMA && ACPI && PCI
  1221. select ACPI_NUMA
  1222. ---help---
  1223. Enable ACPI SRAT based node topology detection.
  1224. # Some NUMA nodes have memory ranges that span
  1225. # other nodes. Even though a pfn is valid and
  1226. # between a node's start and end pfns, it may not
  1227. # reside on that node. See memmap_init_zone()
  1228. # for details.
  1229. config NODES_SPAN_OTHER_NODES
  1230. def_bool y
  1231. depends on X86_64_ACPI_NUMA
  1232. config NUMA_EMU
  1233. bool "NUMA emulation"
  1234. depends on NUMA
  1235. ---help---
  1236. Enable NUMA emulation. A flat machine will be split
  1237. into virtual nodes when booted with "numa=fake=N", where N is the
  1238. number of nodes. This is only useful for debugging.
  1239. config NODES_SHIFT
  1240. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1241. range 1 10
  1242. default "10" if MAXSMP
  1243. default "6" if X86_64
  1244. default "3"
  1245. depends on NEED_MULTIPLE_NODES
  1246. ---help---
  1247. Specify the maximum number of NUMA Nodes available on the target
  1248. system. Increases memory reserved to accommodate various tables.
  1249. config ARCH_HAVE_MEMORY_PRESENT
  1250. def_bool y
  1251. depends on X86_32 && DISCONTIGMEM
  1252. config NEED_NODE_MEMMAP_SIZE
  1253. def_bool y
  1254. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1255. config ARCH_FLATMEM_ENABLE
  1256. def_bool y
  1257. depends on X86_32 && !NUMA
  1258. config ARCH_DISCONTIGMEM_ENABLE
  1259. def_bool y
  1260. depends on NUMA && X86_32
  1261. config ARCH_DISCONTIGMEM_DEFAULT
  1262. def_bool y
  1263. depends on NUMA && X86_32
  1264. config ARCH_SPARSEMEM_ENABLE
  1265. def_bool y
  1266. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1267. select SPARSEMEM_STATIC if X86_32
  1268. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1269. config ARCH_SPARSEMEM_DEFAULT
  1270. def_bool y
  1271. depends on X86_64
  1272. config ARCH_SELECT_MEMORY_MODEL
  1273. def_bool y
  1274. depends on ARCH_SPARSEMEM_ENABLE
  1275. config ARCH_MEMORY_PROBE
  1276. bool "Enable sysfs memory/probe interface"
  1277. depends on X86_64 && MEMORY_HOTPLUG
  1278. help
  1279. This option enables a sysfs memory/probe interface for testing.
  1280. See Documentation/memory-hotplug.txt for more information.
  1281. If you are unsure how to answer this question, answer N.
  1282. config ARCH_PROC_KCORE_TEXT
  1283. def_bool y
  1284. depends on X86_64 && PROC_KCORE
  1285. config ILLEGAL_POINTER_VALUE
  1286. hex
  1287. default 0 if X86_32
  1288. default 0xdead000000000000 if X86_64
  1289. source "mm/Kconfig"
  1290. config X86_PMEM_LEGACY_DEVICE
  1291. bool
  1292. config X86_PMEM_LEGACY
  1293. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1294. depends on PHYS_ADDR_T_64BIT
  1295. depends on BLK_DEV
  1296. select X86_PMEM_LEGACY_DEVICE
  1297. select LIBNVDIMM
  1298. help
  1299. Treat memory marked using the non-standard e820 type of 12 as used
  1300. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1301. The kernel will offer these regions to the 'pmem' driver so
  1302. they can be used for persistent storage.
  1303. Say Y if unsure.
  1304. config HIGHPTE
  1305. bool "Allocate 3rd-level pagetables from highmem"
  1306. depends on HIGHMEM
  1307. ---help---
  1308. The VM uses one page table entry for each page of physical memory.
  1309. For systems with a lot of RAM, this can be wasteful of precious
  1310. low memory. Setting this option will put user-space page table
  1311. entries in high memory.
  1312. config X86_CHECK_BIOS_CORRUPTION
  1313. bool "Check for low memory corruption"
  1314. ---help---
  1315. Periodically check for memory corruption in low memory, which
  1316. is suspected to be caused by BIOS. Even when enabled in the
  1317. configuration, it is disabled at runtime. Enable it by
  1318. setting "memory_corruption_check=1" on the kernel command
  1319. line. By default it scans the low 64k of memory every 60
  1320. seconds; see the memory_corruption_check_size and
  1321. memory_corruption_check_period parameters in
  1322. Documentation/admin-guide/kernel-parameters.rst to adjust this.
  1323. When enabled with the default parameters, this option has
  1324. almost no overhead, as it reserves a relatively small amount
  1325. of memory and scans it infrequently. It both detects corruption
  1326. and prevents it from affecting the running system.
  1327. It is, however, intended as a diagnostic tool; if repeatable
  1328. BIOS-originated corruption always affects the same memory,
  1329. you can use memmap= to prevent the kernel from using that
  1330. memory.
  1331. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1332. bool "Set the default setting of memory_corruption_check"
  1333. depends on X86_CHECK_BIOS_CORRUPTION
  1334. default y
  1335. ---help---
  1336. Set whether the default state of memory_corruption_check is
  1337. on or off.
  1338. config X86_RESERVE_LOW
  1339. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1340. default 64
  1341. range 4 640
  1342. ---help---
  1343. Specify the amount of low memory to reserve for the BIOS.
  1344. The first page contains BIOS data structures that the kernel
  1345. must not use, so that page must always be reserved.
  1346. By default we reserve the first 64K of physical RAM, as a
  1347. number of BIOSes are known to corrupt that memory range
  1348. during events such as suspend/resume or monitor cable
  1349. insertion, so it must not be used by the kernel.
  1350. You can set this to 4 if you are absolutely sure that you
  1351. trust the BIOS to get all its memory reservations and usages
  1352. right. If you know your BIOS have problems beyond the
  1353. default 64K area, you can set this to 640 to avoid using the
  1354. entire low memory range.
  1355. If you have doubts about the BIOS (e.g. suspend/resume does
  1356. not work or there's kernel crashes after certain hardware
  1357. hotplug events) then you might want to enable
  1358. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1359. typical corruption patterns.
  1360. Leave this to the default value of 64 if you are unsure.
  1361. config MATH_EMULATION
  1362. bool
  1363. depends on MODIFY_LDT_SYSCALL
  1364. prompt "Math emulation" if X86_32
  1365. ---help---
  1366. Linux can emulate a math coprocessor (used for floating point
  1367. operations) if you don't have one. 486DX and Pentium processors have
  1368. a math coprocessor built in, 486SX and 386 do not, unless you added
  1369. a 487DX or 387, respectively. (The messages during boot time can
  1370. give you some hints here ["man dmesg"].) Everyone needs either a
  1371. coprocessor or this emulation.
  1372. If you don't have a math coprocessor, you need to say Y here; if you
  1373. say Y here even though you have a coprocessor, the coprocessor will
  1374. be used nevertheless. (This behavior can be changed with the kernel
  1375. command line option "no387", which comes handy if your coprocessor
  1376. is broken. Try "man bootparam" or see the documentation of your boot
  1377. loader (lilo or loadlin) about how to pass options to the kernel at
  1378. boot time.) This means that it is a good idea to say Y here if you
  1379. intend to use this kernel on different machines.
  1380. More information about the internals of the Linux math coprocessor
  1381. emulation can be found in <file:arch/x86/math-emu/README>.
  1382. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1383. kernel, it won't hurt.
  1384. config MTRR
  1385. def_bool y
  1386. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1387. ---help---
  1388. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1389. the Memory Type Range Registers (MTRRs) may be used to control
  1390. processor access to memory ranges. This is most useful if you have
  1391. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1392. allows bus write transfers to be combined into a larger transfer
  1393. before bursting over the PCI/AGP bus. This can increase performance
  1394. of image write operations 2.5 times or more. Saying Y here creates a
  1395. /proc/mtrr file which may be used to manipulate your processor's
  1396. MTRRs. Typically the X server should use this.
  1397. This code has a reasonably generic interface so that similar
  1398. control registers on other processors can be easily supported
  1399. as well:
  1400. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1401. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1402. these, the ARRs are used to emulate the MTRRs.
  1403. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1404. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1405. write-combining. All of these processors are supported by this code
  1406. and it makes sense to say Y here if you have one of them.
  1407. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1408. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1409. can lead to all sorts of problems, so it's good to say Y here.
  1410. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1411. just add about 9 KB to your kernel.
  1412. See <file:Documentation/x86/mtrr.txt> for more information.
  1413. config MTRR_SANITIZER
  1414. def_bool y
  1415. prompt "MTRR cleanup support"
  1416. depends on MTRR
  1417. ---help---
  1418. Convert MTRR layout from continuous to discrete, so X drivers can
  1419. add writeback entries.
  1420. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1421. The largest mtrr entry size for a continuous block can be set with
  1422. mtrr_chunk_size.
  1423. If unsure, say Y.
  1424. config MTRR_SANITIZER_ENABLE_DEFAULT
  1425. int "MTRR cleanup enable value (0-1)"
  1426. range 0 1
  1427. default "0"
  1428. depends on MTRR_SANITIZER
  1429. ---help---
  1430. Enable mtrr cleanup default value
  1431. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1432. int "MTRR cleanup spare reg num (0-7)"
  1433. range 0 7
  1434. default "1"
  1435. depends on MTRR_SANITIZER
  1436. ---help---
  1437. mtrr cleanup spare entries default, it can be changed via
  1438. mtrr_spare_reg_nr=N on the kernel command line.
  1439. config X86_PAT
  1440. def_bool y
  1441. prompt "x86 PAT support" if EXPERT
  1442. depends on MTRR
  1443. ---help---
  1444. Use PAT attributes to setup page level cache control.
  1445. PATs are the modern equivalents of MTRRs and are much more
  1446. flexible than MTRRs.
  1447. Say N here if you see bootup problems (boot crash, boot hang,
  1448. spontaneous reboots) or a non-working video driver.
  1449. If unsure, say Y.
  1450. config ARCH_USES_PG_UNCACHED
  1451. def_bool y
  1452. depends on X86_PAT
  1453. config ARCH_RANDOM
  1454. def_bool y
  1455. prompt "x86 architectural random number generator" if EXPERT
  1456. ---help---
  1457. Enable the x86 architectural RDRAND instruction
  1458. (Intel Bull Mountain technology) to generate random numbers.
  1459. If supported, this is a high bandwidth, cryptographically
  1460. secure hardware random number generator.
  1461. config X86_SMAP
  1462. def_bool y
  1463. prompt "Supervisor Mode Access Prevention" if EXPERT
  1464. ---help---
  1465. Supervisor Mode Access Prevention (SMAP) is a security
  1466. feature in newer Intel processors. There is a small
  1467. performance cost if this enabled and turned on; there is
  1468. also a small increase in the kernel size if this is enabled.
  1469. If unsure, say Y.
  1470. config X86_INTEL_MPX
  1471. prompt "Intel MPX (Memory Protection Extensions)"
  1472. def_bool n
  1473. depends on CPU_SUP_INTEL
  1474. ---help---
  1475. MPX provides hardware features that can be used in
  1476. conjunction with compiler-instrumented code to check
  1477. memory references. It is designed to detect buffer
  1478. overflow or underflow bugs.
  1479. This option enables running applications which are
  1480. instrumented or otherwise use MPX. It does not use MPX
  1481. itself inside the kernel or to protect the kernel
  1482. against bad memory references.
  1483. Enabling this option will make the kernel larger:
  1484. ~8k of kernel text and 36 bytes of data on a 64-bit
  1485. defconfig. It adds a long to the 'mm_struct' which
  1486. will increase the kernel memory overhead of each
  1487. process and adds some branches to paths used during
  1488. exec() and munmap().
  1489. For details, see Documentation/x86/intel_mpx.txt
  1490. If unsure, say N.
  1491. config X86_INTEL_MEMORY_PROTECTION_KEYS
  1492. prompt "Intel Memory Protection Keys"
  1493. def_bool y
  1494. # Note: only available in 64-bit mode
  1495. depends on CPU_SUP_INTEL && X86_64
  1496. select ARCH_USES_HIGH_VMA_FLAGS
  1497. select ARCH_HAS_PKEYS
  1498. ---help---
  1499. Memory Protection Keys provides a mechanism for enforcing
  1500. page-based protections, but without requiring modification of the
  1501. page tables when an application changes protection domains.
  1502. For details, see Documentation/x86/protection-keys.txt
  1503. If unsure, say y.
  1504. config EFI
  1505. bool "EFI runtime service support"
  1506. depends on ACPI
  1507. select UCS2_STRING
  1508. select EFI_RUNTIME_WRAPPERS
  1509. ---help---
  1510. This enables the kernel to use EFI runtime services that are
  1511. available (such as the EFI variable services).
  1512. This option is only useful on systems that have EFI firmware.
  1513. In addition, you should use the latest ELILO loader available
  1514. at <http://elilo.sourceforge.net> in order to take advantage
  1515. of EFI runtime services. However, even with this option, the
  1516. resultant kernel should continue to boot on existing non-EFI
  1517. platforms.
  1518. config EFI_STUB
  1519. bool "EFI stub support"
  1520. depends on EFI && !X86_USE_3DNOW
  1521. select RELOCATABLE
  1522. ---help---
  1523. This kernel feature allows a bzImage to be loaded directly
  1524. by EFI firmware without the use of a bootloader.
  1525. See Documentation/efi-stub.txt for more information.
  1526. config EFI_MIXED
  1527. bool "EFI mixed-mode support"
  1528. depends on EFI_STUB && X86_64
  1529. ---help---
  1530. Enabling this feature allows a 64-bit kernel to be booted
  1531. on a 32-bit firmware, provided that your CPU supports 64-bit
  1532. mode.
  1533. Note that it is not possible to boot a mixed-mode enabled
  1534. kernel via the EFI boot stub - a bootloader that supports
  1535. the EFI handover protocol must be used.
  1536. If unsure, say N.
  1537. config SECCOMP
  1538. def_bool y
  1539. prompt "Enable seccomp to safely compute untrusted bytecode"
  1540. ---help---
  1541. This kernel feature is useful for number crunching applications
  1542. that may need to compute untrusted bytecode during their
  1543. execution. By using pipes or other transports made available to
  1544. the process as file descriptors supporting the read/write
  1545. syscalls, it's possible to isolate those applications in
  1546. their own address space using seccomp. Once seccomp is
  1547. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1548. and the task is only allowed to execute a few safe syscalls
  1549. defined by each seccomp mode.
  1550. If unsure, say Y. Only embedded should say N here.
  1551. source kernel/Kconfig.hz
  1552. config KEXEC
  1553. bool "kexec system call"
  1554. select KEXEC_CORE
  1555. ---help---
  1556. kexec is a system call that implements the ability to shutdown your
  1557. current kernel, and to start another kernel. It is like a reboot
  1558. but it is independent of the system firmware. And like a reboot
  1559. you can start any kernel with it, not just Linux.
  1560. The name comes from the similarity to the exec system call.
  1561. It is an ongoing process to be certain the hardware in a machine
  1562. is properly shutdown, so do not be surprised if this code does not
  1563. initially work for you. As of this writing the exact hardware
  1564. interface is strongly in flux, so no good recommendation can be
  1565. made.
  1566. config KEXEC_FILE
  1567. bool "kexec file based system call"
  1568. select KEXEC_CORE
  1569. select BUILD_BIN2C
  1570. depends on X86_64
  1571. depends on CRYPTO=y
  1572. depends on CRYPTO_SHA256=y
  1573. ---help---
  1574. This is new version of kexec system call. This system call is
  1575. file based and takes file descriptors as system call argument
  1576. for kernel and initramfs as opposed to list of segments as
  1577. accepted by previous system call.
  1578. config KEXEC_VERIFY_SIG
  1579. bool "Verify kernel signature during kexec_file_load() syscall"
  1580. depends on KEXEC_FILE
  1581. ---help---
  1582. This option makes kernel signature verification mandatory for
  1583. the kexec_file_load() syscall.
  1584. In addition to that option, you need to enable signature
  1585. verification for the corresponding kernel image type being
  1586. loaded in order for this to work.
  1587. config KEXEC_BZIMAGE_VERIFY_SIG
  1588. bool "Enable bzImage signature verification support"
  1589. depends on KEXEC_VERIFY_SIG
  1590. depends on SIGNED_PE_FILE_VERIFICATION
  1591. select SYSTEM_TRUSTED_KEYRING
  1592. ---help---
  1593. Enable bzImage signature verification support.
  1594. config CRASH_DUMP
  1595. bool "kernel crash dumps"
  1596. depends on X86_64 || (X86_32 && HIGHMEM)
  1597. ---help---
  1598. Generate crash dump after being started by kexec.
  1599. This should be normally only set in special crash dump kernels
  1600. which are loaded in the main kernel with kexec-tools into
  1601. a specially reserved region and then later executed after
  1602. a crash by kdump/kexec. The crash dump kernel must be compiled
  1603. to a memory address not used by the main kernel or BIOS using
  1604. PHYSICAL_START, or it must be built as a relocatable image
  1605. (CONFIG_RELOCATABLE=y).
  1606. For more details see Documentation/kdump/kdump.txt
  1607. config KEXEC_JUMP
  1608. bool "kexec jump"
  1609. depends on KEXEC && HIBERNATION
  1610. ---help---
  1611. Jump between original kernel and kexeced kernel and invoke
  1612. code in physical address mode via KEXEC
  1613. config PHYSICAL_START
  1614. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1615. default "0x1000000"
  1616. ---help---
  1617. This gives the physical address where the kernel is loaded.
  1618. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1619. bzImage will decompress itself to above physical address and
  1620. run from there. Otherwise, bzImage will run from the address where
  1621. it has been loaded by the boot loader and will ignore above physical
  1622. address.
  1623. In normal kdump cases one does not have to set/change this option
  1624. as now bzImage can be compiled as a completely relocatable image
  1625. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1626. address. This option is mainly useful for the folks who don't want
  1627. to use a bzImage for capturing the crash dump and want to use a
  1628. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1629. to be specifically compiled to run from a specific memory area
  1630. (normally a reserved region) and this option comes handy.
  1631. So if you are using bzImage for capturing the crash dump,
  1632. leave the value here unchanged to 0x1000000 and set
  1633. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1634. for capturing the crash dump change this value to start of
  1635. the reserved region. In other words, it can be set based on
  1636. the "X" value as specified in the "crashkernel=YM@XM"
  1637. command line boot parameter passed to the panic-ed
  1638. kernel. Please take a look at Documentation/kdump/kdump.txt
  1639. for more details about crash dumps.
  1640. Usage of bzImage for capturing the crash dump is recommended as
  1641. one does not have to build two kernels. Same kernel can be used
  1642. as production kernel and capture kernel. Above option should have
  1643. gone away after relocatable bzImage support is introduced. But it
  1644. is present because there are users out there who continue to use
  1645. vmlinux for dump capture. This option should go away down the
  1646. line.
  1647. Don't change this unless you know what you are doing.
  1648. config RELOCATABLE
  1649. bool "Build a relocatable kernel"
  1650. default y
  1651. ---help---
  1652. This builds a kernel image that retains relocation information
  1653. so it can be loaded someplace besides the default 1MB.
  1654. The relocations tend to make the kernel binary about 10% larger,
  1655. but are discarded at runtime.
  1656. One use is for the kexec on panic case where the recovery kernel
  1657. must live at a different physical address than the primary
  1658. kernel.
  1659. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1660. it has been loaded at and the compile time physical address
  1661. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1662. config RANDOMIZE_BASE
  1663. bool "Randomize the address of the kernel image (KASLR)"
  1664. depends on RELOCATABLE
  1665. default n
  1666. ---help---
  1667. In support of Kernel Address Space Layout Randomization (KASLR),
  1668. this randomizes the physical address at which the kernel image
  1669. is decompressed and the virtual address where the kernel
  1670. image is mapped, as a security feature that deters exploit
  1671. attempts relying on knowledge of the location of kernel
  1672. code internals.
  1673. On 64-bit, the kernel physical and virtual addresses are
  1674. randomized separately. The physical address will be anywhere
  1675. between 16MB and the top of physical memory (up to 64TB). The
  1676. virtual address will be randomized from 16MB up to 1GB (9 bits
  1677. of entropy). Note that this also reduces the memory space
  1678. available to kernel modules from 1.5GB to 1GB.
  1679. On 32-bit, the kernel physical and virtual addresses are
  1680. randomized together. They will be randomized from 16MB up to
  1681. 512MB (8 bits of entropy).
  1682. Entropy is generated using the RDRAND instruction if it is
  1683. supported. If RDTSC is supported, its value is mixed into
  1684. the entropy pool as well. If neither RDRAND nor RDTSC are
  1685. supported, then entropy is read from the i8254 timer. The
  1686. usable entropy is limited by the kernel being built using
  1687. 2GB addressing, and that PHYSICAL_ALIGN must be at a
  1688. minimum of 2MB. As a result, only 10 bits of entropy are
  1689. theoretically possible, but the implementations are further
  1690. limited due to memory layouts.
  1691. If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot
  1692. time. To enable it, boot with "kaslr" on the kernel command
  1693. line (which will also disable hibernation).
  1694. If unsure, say N.
  1695. # Relocation on x86 needs some additional build support
  1696. config X86_NEED_RELOCS
  1697. def_bool y
  1698. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1699. config PHYSICAL_ALIGN
  1700. hex "Alignment value to which kernel should be aligned"
  1701. default "0x200000"
  1702. range 0x2000 0x1000000 if X86_32
  1703. range 0x200000 0x1000000 if X86_64
  1704. ---help---
  1705. This value puts the alignment restrictions on physical address
  1706. where kernel is loaded and run from. Kernel is compiled for an
  1707. address which meets above alignment restriction.
  1708. If bootloader loads the kernel at a non-aligned address and
  1709. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1710. address aligned to above value and run from there.
  1711. If bootloader loads the kernel at a non-aligned address and
  1712. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1713. load address and decompress itself to the address it has been
  1714. compiled for and run from there. The address for which kernel is
  1715. compiled already meets above alignment restrictions. Hence the
  1716. end result is that kernel runs from a physical address meeting
  1717. above alignment restrictions.
  1718. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1719. this value must be a multiple of 0x200000.
  1720. Don't change this unless you know what you are doing.
  1721. config RANDOMIZE_MEMORY
  1722. bool "Randomize the kernel memory sections"
  1723. depends on X86_64
  1724. depends on RANDOMIZE_BASE
  1725. default RANDOMIZE_BASE
  1726. ---help---
  1727. Randomizes the base virtual address of kernel memory sections
  1728. (physical memory mapping, vmalloc & vmemmap). This security feature
  1729. makes exploits relying on predictable memory locations less reliable.
  1730. The order of allocations remains unchanged. Entropy is generated in
  1731. the same way as RANDOMIZE_BASE. Current implementation in the optimal
  1732. configuration have in average 30,000 different possible virtual
  1733. addresses for each memory section.
  1734. If unsure, say N.
  1735. config RANDOMIZE_MEMORY_PHYSICAL_PADDING
  1736. hex "Physical memory mapping padding" if EXPERT
  1737. depends on RANDOMIZE_MEMORY
  1738. default "0xa" if MEMORY_HOTPLUG
  1739. default "0x0"
  1740. range 0x1 0x40 if MEMORY_HOTPLUG
  1741. range 0x0 0x40
  1742. ---help---
  1743. Define the padding in terabytes added to the existing physical
  1744. memory size during kernel memory randomization. It is useful
  1745. for memory hotplug support but reduces the entropy available for
  1746. address randomization.
  1747. If unsure, leave at the default value.
  1748. config HOTPLUG_CPU
  1749. bool "Support for hot-pluggable CPUs"
  1750. depends on SMP
  1751. ---help---
  1752. Say Y here to allow turning CPUs off and on. CPUs can be
  1753. controlled through /sys/devices/system/cpu.
  1754. ( Note: power management support will enable this option
  1755. automatically on SMP systems. )
  1756. Say N if you want to disable CPU hotplug.
  1757. config BOOTPARAM_HOTPLUG_CPU0
  1758. bool "Set default setting of cpu0_hotpluggable"
  1759. default n
  1760. depends on HOTPLUG_CPU
  1761. ---help---
  1762. Set whether default state of cpu0_hotpluggable is on or off.
  1763. Say Y here to enable CPU0 hotplug by default. If this switch
  1764. is turned on, there is no need to give cpu0_hotplug kernel
  1765. parameter and the CPU0 hotplug feature is enabled by default.
  1766. Please note: there are two known CPU0 dependencies if you want
  1767. to enable the CPU0 hotplug feature either by this switch or by
  1768. cpu0_hotplug kernel parameter.
  1769. First, resume from hibernate or suspend always starts from CPU0.
  1770. So hibernate and suspend are prevented if CPU0 is offline.
  1771. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1772. offline if any interrupt can not migrate out of CPU0. There may
  1773. be other CPU0 dependencies.
  1774. Please make sure the dependencies are under your control before
  1775. you enable this feature.
  1776. Say N if you don't want to enable CPU0 hotplug feature by default.
  1777. You still can enable the CPU0 hotplug feature at boot by kernel
  1778. parameter cpu0_hotplug.
  1779. config DEBUG_HOTPLUG_CPU0
  1780. def_bool n
  1781. prompt "Debug CPU0 hotplug"
  1782. depends on HOTPLUG_CPU
  1783. ---help---
  1784. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1785. soon as possible and boots up userspace with CPU0 offlined. User
  1786. can online CPU0 back after boot time.
  1787. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1788. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1789. compilation or giving cpu0_hotplug kernel parameter at boot.
  1790. If unsure, say N.
  1791. config COMPAT_VDSO
  1792. def_bool n
  1793. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1794. depends on COMPAT_32
  1795. ---help---
  1796. Certain buggy versions of glibc will crash if they are
  1797. presented with a 32-bit vDSO that is not mapped at the address
  1798. indicated in its segment table.
  1799. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1800. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1801. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1802. the only released version with the bug, but OpenSUSE 9
  1803. contains a buggy "glibc 2.3.2".
  1804. The symptom of the bug is that everything crashes on startup, saying:
  1805. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1806. Saying Y here changes the default value of the vdso32 boot
  1807. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1808. This works around the glibc bug but hurts performance.
  1809. If unsure, say N: if you are compiling your own kernel, you
  1810. are unlikely to be using a buggy version of glibc.
  1811. choice
  1812. prompt "vsyscall table for legacy applications"
  1813. depends on X86_64
  1814. default LEGACY_VSYSCALL_EMULATE
  1815. help
  1816. Legacy user code that does not know how to find the vDSO expects
  1817. to be able to issue three syscalls by calling fixed addresses in
  1818. kernel space. Since this location is not randomized with ASLR,
  1819. it can be used to assist security vulnerability exploitation.
  1820. This setting can be changed at boot time via the kernel command
  1821. line parameter vsyscall=[native|emulate|none].
  1822. On a system with recent enough glibc (2.14 or newer) and no
  1823. static binaries, you can say None without a performance penalty
  1824. to improve security.
  1825. If unsure, select "Emulate".
  1826. config LEGACY_VSYSCALL_NATIVE
  1827. bool "Native"
  1828. help
  1829. Actual executable code is located in the fixed vsyscall
  1830. address mapping, implementing time() efficiently. Since
  1831. this makes the mapping executable, it can be used during
  1832. security vulnerability exploitation (traditionally as
  1833. ROP gadgets). This configuration is not recommended.
  1834. config LEGACY_VSYSCALL_EMULATE
  1835. bool "Emulate"
  1836. help
  1837. The kernel traps and emulates calls into the fixed
  1838. vsyscall address mapping. This makes the mapping
  1839. non-executable, but it still contains known contents,
  1840. which could be used in certain rare security vulnerability
  1841. exploits. This configuration is recommended when userspace
  1842. still uses the vsyscall area.
  1843. config LEGACY_VSYSCALL_NONE
  1844. bool "None"
  1845. help
  1846. There will be no vsyscall mapping at all. This will
  1847. eliminate any risk of ASLR bypass due to the vsyscall
  1848. fixed address mapping. Attempts to use the vsyscalls
  1849. will be reported to dmesg, so that either old or
  1850. malicious userspace programs can be identified.
  1851. endchoice
  1852. config CMDLINE_BOOL
  1853. bool "Built-in kernel command line"
  1854. ---help---
  1855. Allow for specifying boot arguments to the kernel at
  1856. build time. On some systems (e.g. embedded ones), it is
  1857. necessary or convenient to provide some or all of the
  1858. kernel boot arguments with the kernel itself (that is,
  1859. to not rely on the boot loader to provide them.)
  1860. To compile command line arguments into the kernel,
  1861. set this option to 'Y', then fill in the
  1862. boot arguments in CONFIG_CMDLINE.
  1863. Systems with fully functional boot loaders (i.e. non-embedded)
  1864. should leave this option set to 'N'.
  1865. config CMDLINE
  1866. string "Built-in kernel command string"
  1867. depends on CMDLINE_BOOL
  1868. default ""
  1869. ---help---
  1870. Enter arguments here that should be compiled into the kernel
  1871. image and used at boot time. If the boot loader provides a
  1872. command line at boot time, it is appended to this string to
  1873. form the full kernel command line, when the system boots.
  1874. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1875. change this behavior.
  1876. In most cases, the command line (whether built-in or provided
  1877. by the boot loader) should specify the device for the root
  1878. file system.
  1879. config CMDLINE_OVERRIDE
  1880. bool "Built-in command line overrides boot loader arguments"
  1881. depends on CMDLINE_BOOL
  1882. ---help---
  1883. Set this option to 'Y' to have the kernel ignore the boot loader
  1884. command line, and use ONLY the built-in command line.
  1885. This is used to work around broken boot loaders. This should
  1886. be set to 'N' under normal conditions.
  1887. config MODIFY_LDT_SYSCALL
  1888. bool "Enable the LDT (local descriptor table)" if EXPERT
  1889. default y
  1890. ---help---
  1891. Linux can allow user programs to install a per-process x86
  1892. Local Descriptor Table (LDT) using the modify_ldt(2) system
  1893. call. This is required to run 16-bit or segmented code such as
  1894. DOSEMU or some Wine programs. It is also used by some very old
  1895. threading libraries.
  1896. Enabling this feature adds a small amount of overhead to
  1897. context switches and increases the low-level kernel attack
  1898. surface. Disabling it removes the modify_ldt(2) system call.
  1899. Saying 'N' here may make sense for embedded or server kernels.
  1900. source "kernel/livepatch/Kconfig"
  1901. endmenu
  1902. config ARCH_ENABLE_MEMORY_HOTPLUG
  1903. def_bool y
  1904. depends on X86_64 || (X86_32 && HIGHMEM)
  1905. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1906. def_bool y
  1907. depends on MEMORY_HOTPLUG
  1908. config USE_PERCPU_NUMA_NODE_ID
  1909. def_bool y
  1910. depends on NUMA
  1911. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  1912. def_bool y
  1913. depends on X86_64 || X86_PAE
  1914. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  1915. def_bool y
  1916. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  1917. menu "Power management and ACPI options"
  1918. config ARCH_HIBERNATION_HEADER
  1919. def_bool y
  1920. depends on X86_64 && HIBERNATION
  1921. source "kernel/power/Kconfig"
  1922. source "drivers/acpi/Kconfig"
  1923. source "drivers/sfi/Kconfig"
  1924. config X86_APM_BOOT
  1925. def_bool y
  1926. depends on APM
  1927. menuconfig APM
  1928. tristate "APM (Advanced Power Management) BIOS support"
  1929. depends on X86_32 && PM_SLEEP
  1930. ---help---
  1931. APM is a BIOS specification for saving power using several different
  1932. techniques. This is mostly useful for battery powered laptops with
  1933. APM compliant BIOSes. If you say Y here, the system time will be
  1934. reset after a RESUME operation, the /proc/apm device will provide
  1935. battery status information, and user-space programs will receive
  1936. notification of APM "events" (e.g. battery status change).
  1937. If you select "Y" here, you can disable actual use of the APM
  1938. BIOS by passing the "apm=off" option to the kernel at boot time.
  1939. Note that the APM support is almost completely disabled for
  1940. machines with more than one CPU.
  1941. In order to use APM, you will need supporting software. For location
  1942. and more information, read <file:Documentation/power/apm-acpi.txt>
  1943. and the Battery Powered Linux mini-HOWTO, available from
  1944. <http://www.tldp.org/docs.html#howto>.
  1945. This driver does not spin down disk drives (see the hdparm(8)
  1946. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1947. VESA-compliant "green" monitors.
  1948. This driver does not support the TI 4000M TravelMate and the ACER
  1949. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1950. desktop machines also don't have compliant BIOSes, and this driver
  1951. may cause those machines to panic during the boot phase.
  1952. Generally, if you don't have a battery in your machine, there isn't
  1953. much point in using this driver and you should say N. If you get
  1954. random kernel OOPSes or reboots that don't seem to be related to
  1955. anything, try disabling/enabling this option (or disabling/enabling
  1956. APM in your BIOS).
  1957. Some other things you should try when experiencing seemingly random,
  1958. "weird" problems:
  1959. 1) make sure that you have enough swap space and that it is
  1960. enabled.
  1961. 2) pass the "no-hlt" option to the kernel
  1962. 3) switch on floating point emulation in the kernel and pass
  1963. the "no387" option to the kernel
  1964. 4) pass the "floppy=nodma" option to the kernel
  1965. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1966. all but the first 4 MB of RAM)
  1967. 6) make sure that the CPU is not over clocked.
  1968. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1969. 8) disable the cache from your BIOS settings
  1970. 9) install a fan for the video card or exchange video RAM
  1971. 10) install a better fan for the CPU
  1972. 11) exchange RAM chips
  1973. 12) exchange the motherboard.
  1974. To compile this driver as a module, choose M here: the
  1975. module will be called apm.
  1976. if APM
  1977. config APM_IGNORE_USER_SUSPEND
  1978. bool "Ignore USER SUSPEND"
  1979. ---help---
  1980. This option will ignore USER SUSPEND requests. On machines with a
  1981. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1982. series notebooks, it is necessary to say Y because of a BIOS bug.
  1983. config APM_DO_ENABLE
  1984. bool "Enable PM at boot time"
  1985. ---help---
  1986. Enable APM features at boot time. From page 36 of the APM BIOS
  1987. specification: "When disabled, the APM BIOS does not automatically
  1988. power manage devices, enter the Standby State, enter the Suspend
  1989. State, or take power saving steps in response to CPU Idle calls."
  1990. This driver will make CPU Idle calls when Linux is idle (unless this
  1991. feature is turned off -- see "Do CPU IDLE calls", below). This
  1992. should always save battery power, but more complicated APM features
  1993. will be dependent on your BIOS implementation. You may need to turn
  1994. this option off if your computer hangs at boot time when using APM
  1995. support, or if it beeps continuously instead of suspending. Turn
  1996. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1997. T400CDT. This is off by default since most machines do fine without
  1998. this feature.
  1999. config APM_CPU_IDLE
  2000. depends on CPU_IDLE
  2001. bool "Make CPU Idle calls when idle"
  2002. ---help---
  2003. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  2004. On some machines, this can activate improved power savings, such as
  2005. a slowed CPU clock rate, when the machine is idle. These idle calls
  2006. are made after the idle loop has run for some length of time (e.g.,
  2007. 333 mS). On some machines, this will cause a hang at boot time or
  2008. whenever the CPU becomes idle. (On machines with more than one CPU,
  2009. this option does nothing.)
  2010. config APM_DISPLAY_BLANK
  2011. bool "Enable console blanking using APM"
  2012. ---help---
  2013. Enable console blanking using the APM. Some laptops can use this to
  2014. turn off the LCD backlight when the screen blanker of the Linux
  2015. virtual console blanks the screen. Note that this is only used by
  2016. the virtual console screen blanker, and won't turn off the backlight
  2017. when using the X Window system. This also doesn't have anything to
  2018. do with your VESA-compliant power-saving monitor. Further, this
  2019. option doesn't work for all laptops -- it might not turn off your
  2020. backlight at all, or it might print a lot of errors to the console,
  2021. especially if you are using gpm.
  2022. config APM_ALLOW_INTS
  2023. bool "Allow interrupts during APM BIOS calls"
  2024. ---help---
  2025. Normally we disable external interrupts while we are making calls to
  2026. the APM BIOS as a measure to lessen the effects of a badly behaving
  2027. BIOS implementation. The BIOS should reenable interrupts if it
  2028. needs to. Unfortunately, some BIOSes do not -- especially those in
  2029. many of the newer IBM Thinkpads. If you experience hangs when you
  2030. suspend, try setting this to Y. Otherwise, say N.
  2031. endif # APM
  2032. source "drivers/cpufreq/Kconfig"
  2033. source "drivers/cpuidle/Kconfig"
  2034. source "drivers/idle/Kconfig"
  2035. endmenu
  2036. menu "Bus options (PCI etc.)"
  2037. config PCI
  2038. bool "PCI support"
  2039. default y
  2040. ---help---
  2041. Find out whether you have a PCI motherboard. PCI is the name of a
  2042. bus system, i.e. the way the CPU talks to the other stuff inside
  2043. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  2044. VESA. If you have PCI, say Y, otherwise N.
  2045. choice
  2046. prompt "PCI access mode"
  2047. depends on X86_32 && PCI
  2048. default PCI_GOANY
  2049. ---help---
  2050. On PCI systems, the BIOS can be used to detect the PCI devices and
  2051. determine their configuration. However, some old PCI motherboards
  2052. have BIOS bugs and may crash if this is done. Also, some embedded
  2053. PCI-based systems don't have any BIOS at all. Linux can also try to
  2054. detect the PCI hardware directly without using the BIOS.
  2055. With this option, you can specify how Linux should detect the
  2056. PCI devices. If you choose "BIOS", the BIOS will be used,
  2057. if you choose "Direct", the BIOS won't be used, and if you
  2058. choose "MMConfig", then PCI Express MMCONFIG will be used.
  2059. If you choose "Any", the kernel will try MMCONFIG, then the
  2060. direct access method and falls back to the BIOS if that doesn't
  2061. work. If unsure, go with the default, which is "Any".
  2062. config PCI_GOBIOS
  2063. bool "BIOS"
  2064. config PCI_GOMMCONFIG
  2065. bool "MMConfig"
  2066. config PCI_GODIRECT
  2067. bool "Direct"
  2068. config PCI_GOOLPC
  2069. bool "OLPC XO-1"
  2070. depends on OLPC
  2071. config PCI_GOANY
  2072. bool "Any"
  2073. endchoice
  2074. config PCI_BIOS
  2075. def_bool y
  2076. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  2077. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  2078. config PCI_DIRECT
  2079. def_bool y
  2080. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  2081. config PCI_MMCONFIG
  2082. def_bool y
  2083. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  2084. config PCI_OLPC
  2085. def_bool y
  2086. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  2087. config PCI_XEN
  2088. def_bool y
  2089. depends on PCI && XEN
  2090. select SWIOTLB_XEN
  2091. config PCI_DOMAINS
  2092. def_bool y
  2093. depends on PCI
  2094. config PCI_MMCONFIG
  2095. bool "Support mmconfig PCI config space access"
  2096. depends on X86_64 && PCI && ACPI
  2097. config PCI_CNB20LE_QUIRK
  2098. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  2099. depends on PCI
  2100. help
  2101. Read the PCI windows out of the CNB20LE host bridge. This allows
  2102. PCI hotplug to work on systems with the CNB20LE chipset which do
  2103. not have ACPI.
  2104. There's no public spec for this chipset, and this functionality
  2105. is known to be incomplete.
  2106. You should say N unless you know you need this.
  2107. source "drivers/pci/Kconfig"
  2108. config ISA_BUS
  2109. bool "ISA-style bus support on modern systems" if EXPERT
  2110. select ISA_BUS_API
  2111. help
  2112. Enables ISA-style drivers on modern systems. This is necessary to
  2113. support PC/104 devices on X86_64 platforms.
  2114. If unsure, say N.
  2115. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2116. config ISA_DMA_API
  2117. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2118. default y
  2119. help
  2120. Enables ISA-style DMA support for devices requiring such controllers.
  2121. If unsure, say Y.
  2122. if X86_32
  2123. config ISA
  2124. bool "ISA support"
  2125. ---help---
  2126. Find out whether you have ISA slots on your motherboard. ISA is the
  2127. name of a bus system, i.e. the way the CPU talks to the other stuff
  2128. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2129. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2130. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2131. config EISA
  2132. bool "EISA support"
  2133. depends on ISA
  2134. ---help---
  2135. The Extended Industry Standard Architecture (EISA) bus was
  2136. developed as an open alternative to the IBM MicroChannel bus.
  2137. The EISA bus provided some of the features of the IBM MicroChannel
  2138. bus while maintaining backward compatibility with cards made for
  2139. the older ISA bus. The EISA bus saw limited use between 1988 and
  2140. 1995 when it was made obsolete by the PCI bus.
  2141. Say Y here if you are building a kernel for an EISA-based machine.
  2142. Otherwise, say N.
  2143. source "drivers/eisa/Kconfig"
  2144. config SCx200
  2145. tristate "NatSemi SCx200 support"
  2146. ---help---
  2147. This provides basic support for National Semiconductor's
  2148. (now AMD's) Geode processors. The driver probes for the
  2149. PCI-IDs of several on-chip devices, so its a good dependency
  2150. for other scx200_* drivers.
  2151. If compiled as a module, the driver is named scx200.
  2152. config SCx200HR_TIMER
  2153. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2154. depends on SCx200
  2155. default y
  2156. ---help---
  2157. This driver provides a clocksource built upon the on-chip
  2158. 27MHz high-resolution timer. Its also a workaround for
  2159. NSC Geode SC-1100's buggy TSC, which loses time when the
  2160. processor goes idle (as is done by the scheduler). The
  2161. other workaround is idle=poll boot option.
  2162. config OLPC
  2163. bool "One Laptop Per Child support"
  2164. depends on !X86_PAE
  2165. select GPIOLIB
  2166. select OF
  2167. select OF_PROMTREE
  2168. select IRQ_DOMAIN
  2169. ---help---
  2170. Add support for detecting the unique features of the OLPC
  2171. XO hardware.
  2172. config OLPC_XO1_PM
  2173. bool "OLPC XO-1 Power Management"
  2174. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2175. select MFD_CORE
  2176. ---help---
  2177. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2178. config OLPC_XO1_RTC
  2179. bool "OLPC XO-1 Real Time Clock"
  2180. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2181. ---help---
  2182. Add support for the XO-1 real time clock, which can be used as a
  2183. programmable wakeup source.
  2184. config OLPC_XO1_SCI
  2185. bool "OLPC XO-1 SCI extras"
  2186. depends on OLPC && OLPC_XO1_PM
  2187. depends on INPUT=y
  2188. select POWER_SUPPLY
  2189. select GPIO_CS5535
  2190. select MFD_CORE
  2191. ---help---
  2192. Add support for SCI-based features of the OLPC XO-1 laptop:
  2193. - EC-driven system wakeups
  2194. - Power button
  2195. - Ebook switch
  2196. - Lid switch
  2197. - AC adapter status updates
  2198. - Battery status updates
  2199. config OLPC_XO15_SCI
  2200. bool "OLPC XO-1.5 SCI extras"
  2201. depends on OLPC && ACPI
  2202. select POWER_SUPPLY
  2203. ---help---
  2204. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2205. - EC-driven system wakeups
  2206. - AC adapter status updates
  2207. - Battery status updates
  2208. config ALIX
  2209. bool "PCEngines ALIX System Support (LED setup)"
  2210. select GPIOLIB
  2211. ---help---
  2212. This option enables system support for the PCEngines ALIX.
  2213. At present this just sets up LEDs for GPIO control on
  2214. ALIX2/3/6 boards. However, other system specific setup should
  2215. get added here.
  2216. Note: You must still enable the drivers for GPIO and LED support
  2217. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2218. Note: You have to set alix.force=1 for boards with Award BIOS.
  2219. config NET5501
  2220. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2221. select GPIOLIB
  2222. ---help---
  2223. This option enables system support for the Soekris Engineering net5501.
  2224. config GEOS
  2225. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2226. select GPIOLIB
  2227. depends on DMI
  2228. ---help---
  2229. This option enables system support for the Traverse Technologies GEOS.
  2230. config TS5500
  2231. bool "Technologic Systems TS-5500 platform support"
  2232. depends on MELAN
  2233. select CHECK_SIGNATURE
  2234. select NEW_LEDS
  2235. select LEDS_CLASS
  2236. ---help---
  2237. This option enables system support for the Technologic Systems TS-5500.
  2238. endif # X86_32
  2239. config AMD_NB
  2240. def_bool y
  2241. depends on CPU_SUP_AMD && PCI
  2242. source "drivers/pcmcia/Kconfig"
  2243. config RAPIDIO
  2244. tristate "RapidIO support"
  2245. depends on PCI
  2246. default n
  2247. help
  2248. If enabled this option will include drivers and the core
  2249. infrastructure code to support RapidIO interconnect devices.
  2250. source "drivers/rapidio/Kconfig"
  2251. config X86_SYSFB
  2252. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2253. help
  2254. Firmwares often provide initial graphics framebuffers so the BIOS,
  2255. bootloader or kernel can show basic video-output during boot for
  2256. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2257. Extensions and EFI-framebuffers for this, which are mostly limited
  2258. to x86.
  2259. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2260. framebuffers so the new generic system-framebuffer drivers can be
  2261. used on x86. If the framebuffer is not compatible with the generic
  2262. modes, it is adverticed as fallback platform framebuffer so legacy
  2263. drivers like efifb, vesafb and uvesafb can pick it up.
  2264. If this option is not selected, all system framebuffers are always
  2265. marked as fallback platform framebuffers as usual.
  2266. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2267. not be able to pick up generic system framebuffers if this option
  2268. is selected. You are highly encouraged to enable simplefb as
  2269. replacement if you select this option. simplefb can correctly deal
  2270. with generic system framebuffers. But you should still keep vesafb
  2271. and others enabled as fallback if a system framebuffer is
  2272. incompatible with simplefb.
  2273. If unsure, say Y.
  2274. endmenu
  2275. menu "Executable file formats / Emulations"
  2276. source "fs/Kconfig.binfmt"
  2277. config IA32_EMULATION
  2278. bool "IA32 Emulation"
  2279. depends on X86_64
  2280. select ARCH_WANT_OLD_COMPAT_IPC
  2281. select BINFMT_ELF
  2282. select COMPAT_BINFMT_ELF
  2283. select COMPAT_OLD_SIGACTION
  2284. ---help---
  2285. Include code to run legacy 32-bit programs under a
  2286. 64-bit kernel. You should likely turn this on, unless you're
  2287. 100% sure that you don't have any 32-bit programs left.
  2288. config IA32_AOUT
  2289. tristate "IA32 a.out support"
  2290. depends on IA32_EMULATION
  2291. ---help---
  2292. Support old a.out binaries in the 32bit emulation.
  2293. config X86_X32
  2294. bool "x32 ABI for 64-bit mode"
  2295. depends on X86_64
  2296. ---help---
  2297. Include code to run binaries for the x32 native 32-bit ABI
  2298. for 64-bit processors. An x32 process gets access to the
  2299. full 64-bit register file and wide data path while leaving
  2300. pointers at 32 bits for smaller memory footprint.
  2301. You will need a recent binutils (2.22 or later) with
  2302. elf32_x86_64 support enabled to compile a kernel with this
  2303. option set.
  2304. config COMPAT_32
  2305. def_bool y
  2306. depends on IA32_EMULATION || X86_32
  2307. select HAVE_UID16
  2308. select OLD_SIGSUSPEND3
  2309. config COMPAT
  2310. def_bool y
  2311. depends on IA32_EMULATION || X86_X32
  2312. if COMPAT
  2313. config COMPAT_FOR_U64_ALIGNMENT
  2314. def_bool y
  2315. config SYSVIPC_COMPAT
  2316. def_bool y
  2317. depends on SYSVIPC
  2318. config KEYS_COMPAT
  2319. def_bool y
  2320. depends on KEYS
  2321. endif
  2322. endmenu
  2323. config HAVE_ATOMIC_IOMAP
  2324. def_bool y
  2325. depends on X86_32
  2326. config X86_DEV_DMA_OPS
  2327. bool
  2328. depends on X86_64 || STA2X11
  2329. config X86_DMA_REMAP
  2330. bool
  2331. depends on STA2X11
  2332. config PMC_ATOM
  2333. def_bool y
  2334. depends on PCI
  2335. source "net/Kconfig"
  2336. source "drivers/Kconfig"
  2337. source "drivers/firmware/Kconfig"
  2338. source "fs/Kconfig"
  2339. source "arch/x86/Kconfig.debug"
  2340. source "security/Kconfig"
  2341. source "crypto/Kconfig"
  2342. source "arch/x86/kvm/Kconfig"
  2343. source "lib/Kconfig"