Kconfig 89 KB

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