Kconfig 87 KB

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  1. # Select 32 or 64 bit
  2. config 64BIT
  3. bool "64-bit kernel" if ARCH = "x86"
  4. default ARCH != "i386"
  5. ---help---
  6. Say yes to build a 64-bit kernel - formerly known as x86_64
  7. Say no to build a 32-bit kernel - formerly known as i386
  8. config X86_32
  9. def_bool y
  10. depends on !64BIT
  11. config X86_64
  12. def_bool y
  13. depends on 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select ACPI_LEGACY_TABLES_LOOKUP if ACPI
  18. select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
  19. select ANON_INODES
  20. select ARCH_CLOCKSOURCE_DATA
  21. select ARCH_DISCARD_MEMBLOCK
  22. select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  23. select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
  24. select ARCH_HAS_ELF_RANDOMIZE
  25. select ARCH_HAS_FAST_MULTIPLIER
  26. select ARCH_HAS_GCOV_PROFILE_ALL
  27. select ARCH_HAS_PMEM_API if X86_64
  28. select ARCH_HAS_MMIO_FLUSH
  29. select ARCH_HAS_SG_CHAIN
  30. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  31. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  32. select ARCH_MIGHT_HAVE_PC_PARPORT
  33. select ARCH_MIGHT_HAVE_PC_SERIO
  34. select ARCH_SUPPORTS_ATOMIC_RMW
  35. select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
  36. select ARCH_SUPPORTS_INT128 if X86_64
  37. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  38. select ARCH_USE_BUILTIN_BSWAP
  39. select ARCH_USE_CMPXCHG_LOCKREF if X86_64
  40. select ARCH_USE_QUEUED_RWLOCKS
  41. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
  42. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  43. select ARCH_WANT_FRAME_POINTERS
  44. select ARCH_WANT_IPC_PARSE_VERSION if X86_32
  45. select ARCH_WANT_OPTIONAL_GPIOLIB
  46. select BUILDTIME_EXTABLE_SORT
  47. select CLKEVT_I8253
  48. select CLKSRC_I8253 if X86_32
  49. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  50. select CLOCKSOURCE_WATCHDOG
  51. select CLONE_BACKWARDS if X86_32
  52. select COMPAT_OLD_SIGACTION if IA32_EMULATION
  53. select DCACHE_WORD_ACCESS
  54. select EDAC_ATOMIC_SCRUB
  55. select EDAC_SUPPORT
  56. select GENERIC_CLOCKEVENTS
  57. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  58. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  59. select GENERIC_CMOS_UPDATE
  60. select GENERIC_CPU_AUTOPROBE
  61. select GENERIC_CPU_VULNERABILITIES
  62. select GENERIC_EARLY_IOREMAP
  63. select GENERIC_FIND_FIRST_BIT
  64. select GENERIC_IOMAP
  65. select GENERIC_IRQ_PROBE
  66. select GENERIC_IRQ_SHOW
  67. select GENERIC_PENDING_IRQ if SMP
  68. select GENERIC_SMP_IDLE_THREAD
  69. select GENERIC_STRNCPY_FROM_USER
  70. select GENERIC_STRNLEN_USER
  71. select GENERIC_TIME_VSYSCALL
  72. select HAVE_ACPI_APEI if ACPI
  73. select HAVE_ACPI_APEI_NMI if ACPI
  74. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  75. select HAVE_AOUT if X86_32
  76. select HAVE_ARCH_AUDITSYSCALL
  77. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  78. select HAVE_ARCH_JUMP_LABEL
  79. select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
  80. select HAVE_ARCH_KGDB
  81. select HAVE_ARCH_KMEMCHECK
  82. select HAVE_ARCH_SECCOMP_FILTER
  83. select HAVE_ARCH_SOFT_DIRTY if X86_64
  84. select HAVE_ARCH_TRACEHOOK
  85. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  86. select HAVE_BPF_JIT if X86_64
  87. select HAVE_EBPF_JIT if X86_64
  88. select HAVE_CC_STACKPROTECTOR
  89. select HAVE_CMPXCHG_DOUBLE
  90. select HAVE_CMPXCHG_LOCAL
  91. select HAVE_CONTEXT_TRACKING if X86_64
  92. select HAVE_COPY_THREAD_TLS
  93. select HAVE_C_RECORDMCOUNT
  94. select HAVE_DEBUG_KMEMLEAK
  95. select HAVE_DEBUG_STACKOVERFLOW
  96. select HAVE_DMA_API_DEBUG
  97. select HAVE_DMA_ATTRS
  98. select HAVE_DMA_CONTIGUOUS
  99. select HAVE_DYNAMIC_FTRACE
  100. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  101. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  102. select HAVE_FENTRY if X86_64
  103. select HAVE_FTRACE_MCOUNT_RECORD
  104. select HAVE_FUNCTION_GRAPH_FP_TEST
  105. select HAVE_FUNCTION_GRAPH_TRACER
  106. select HAVE_FUNCTION_TRACER
  107. select HAVE_GENERIC_DMA_COHERENT if X86_32
  108. select HAVE_HW_BREAKPOINT
  109. select HAVE_IDE
  110. select HAVE_IOREMAP_PROT
  111. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  112. select HAVE_IRQ_TIME_ACCOUNTING
  113. select HAVE_KERNEL_BZIP2
  114. select HAVE_KERNEL_GZIP
  115. select HAVE_KERNEL_LZ4
  116. select HAVE_KERNEL_LZMA
  117. select HAVE_KERNEL_LZO
  118. select HAVE_KERNEL_XZ
  119. select HAVE_KPROBES
  120. select HAVE_KPROBES_ON_FTRACE
  121. select HAVE_KRETPROBES
  122. select HAVE_KVM
  123. select HAVE_LIVEPATCH if X86_64
  124. select HAVE_MEMBLOCK
  125. select HAVE_MEMBLOCK_NODE_MAP
  126. select HAVE_MIXED_BREAKPOINTS_REGS
  127. select HAVE_OPROFILE
  128. select HAVE_OPTPROBES
  129. select HAVE_PCSPKR_PLATFORM
  130. select HAVE_PERF_EVENTS
  131. select HAVE_PERF_EVENTS_NMI
  132. select HAVE_PERF_REGS
  133. select HAVE_PERF_USER_STACK_DUMP
  134. select HAVE_REGS_AND_STACK_ACCESS_API
  135. select HAVE_SYSCALL_TRACEPOINTS
  136. select HAVE_UID16 if X86_32 || IA32_EMULATION
  137. select HAVE_UNSTABLE_SCHED_CLOCK
  138. select HAVE_USER_RETURN_NOTIFIER
  139. select IRQ_FORCED_THREADING
  140. select MODULES_USE_ELF_RELA if X86_64
  141. select MODULES_USE_ELF_REL if X86_32
  142. select OLD_SIGACTION if X86_32
  143. select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
  144. select PERF_EVENTS
  145. select RTC_LIB
  146. select SPARSE_IRQ
  147. select SRCU
  148. select SYSCTL_EXCEPTION_TRACE
  149. select USER_STACKTRACE_SUPPORT
  150. select VIRT_TO_BUS
  151. select X86_DEV_DMA_OPS if X86_64
  152. select X86_FEATURE_NAMES if PROC_FS
  153. config INSTRUCTION_DECODER
  154. def_bool y
  155. depends on KPROBES || PERF_EVENTS || UPROBES
  156. config PERF_EVENTS_INTEL_UNCORE
  157. def_bool y
  158. depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
  159. config OUTPUT_FORMAT
  160. string
  161. default "elf32-i386" if X86_32
  162. default "elf64-x86-64" if X86_64
  163. config ARCH_DEFCONFIG
  164. string
  165. default "arch/x86/configs/i386_defconfig" if X86_32
  166. default "arch/x86/configs/x86_64_defconfig" if X86_64
  167. config LOCKDEP_SUPPORT
  168. def_bool y
  169. config STACKTRACE_SUPPORT
  170. def_bool y
  171. config HAVE_LATENCYTOP_SUPPORT
  172. def_bool y
  173. config MMU
  174. def_bool y
  175. config SBUS
  176. bool
  177. config NEED_DMA_MAP_STATE
  178. def_bool y
  179. depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
  180. config NEED_SG_DMA_LENGTH
  181. def_bool y
  182. config GENERIC_ISA_DMA
  183. def_bool y
  184. depends on ISA_DMA_API
  185. config GENERIC_BUG
  186. def_bool y
  187. depends on BUG
  188. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  189. config GENERIC_BUG_RELATIVE_POINTERS
  190. bool
  191. config GENERIC_HWEIGHT
  192. def_bool y
  193. config ARCH_MAY_HAVE_PC_FDC
  194. def_bool y
  195. depends on ISA_DMA_API
  196. config RWSEM_XCHGADD_ALGORITHM
  197. def_bool y
  198. config GENERIC_CALIBRATE_DELAY
  199. def_bool y
  200. config ARCH_HAS_CPU_RELAX
  201. def_bool y
  202. config ARCH_HAS_CACHE_LINE_SIZE
  203. def_bool y
  204. config HAVE_SETUP_PER_CPU_AREA
  205. def_bool y
  206. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  207. def_bool y
  208. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  209. def_bool y
  210. config ARCH_HIBERNATION_POSSIBLE
  211. def_bool y
  212. config ARCH_SUSPEND_POSSIBLE
  213. def_bool y
  214. config ARCH_WANT_HUGE_PMD_SHARE
  215. def_bool y
  216. config ARCH_WANT_GENERAL_HUGETLB
  217. def_bool y
  218. config ZONE_DMA32
  219. def_bool y if X86_64
  220. config AUDIT_ARCH
  221. def_bool y if X86_64
  222. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  223. def_bool y
  224. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  225. def_bool y
  226. config KASAN_SHADOW_OFFSET
  227. hex
  228. depends on KASAN
  229. default 0xdffffc0000000000
  230. config HAVE_INTEL_TXT
  231. def_bool y
  232. depends on INTEL_IOMMU && ACPI
  233. config X86_32_SMP
  234. def_bool y
  235. depends on X86_32 && SMP
  236. config X86_64_SMP
  237. def_bool y
  238. depends on X86_64 && SMP
  239. config X86_32_LAZY_GS
  240. def_bool y
  241. depends on X86_32 && !CC_STACKPROTECTOR
  242. config ARCH_SUPPORTS_UPROBES
  243. def_bool y
  244. config FIX_EARLYCON_MEM
  245. def_bool y
  246. config PGTABLE_LEVELS
  247. int
  248. default 4 if X86_64
  249. default 3 if X86_PAE
  250. default 2
  251. source "init/Kconfig"
  252. source "kernel/Kconfig.freezer"
  253. menu "Processor type and features"
  254. config ZONE_DMA
  255. bool "DMA memory allocation support" if EXPERT
  256. default y
  257. help
  258. DMA memory allocation support allows devices with less than 32-bit
  259. addressing to allocate within the first 16MB of address space.
  260. Disable if no such devices will be used.
  261. If unsure, say Y.
  262. config SMP
  263. bool "Symmetric multi-processing support"
  264. ---help---
  265. This enables support for systems with more than one CPU. If you have
  266. a system with only one CPU, say N. If you have a system with more
  267. than one CPU, say Y.
  268. If you say N here, the kernel will run on uni- and multiprocessor
  269. machines, but will use only one CPU of a multiprocessor machine. If
  270. you say Y here, the kernel will run on many, but not all,
  271. uniprocessor machines. On a uniprocessor machine, the kernel
  272. will run faster if you say N here.
  273. Note that if you say Y here and choose architecture "586" or
  274. "Pentium" under "Processor family", the kernel will not work on 486
  275. architectures. Similarly, multiprocessor kernels for the "PPro"
  276. architecture may not work on all Pentium based boards.
  277. People using multiprocessor machines who say Y here should also say
  278. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  279. Management" code will be disabled if you say Y here.
  280. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  281. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  282. <http://www.tldp.org/docs.html#howto>.
  283. If you don't know what to do here, say N.
  284. config X86_FEATURE_NAMES
  285. bool "Processor feature human-readable names" if EMBEDDED
  286. default y
  287. ---help---
  288. This option compiles in a table of x86 feature bits and corresponding
  289. names. This is required to support /proc/cpuinfo and a few kernel
  290. messages. You can disable this to save space, at the expense of
  291. making those few kernel messages show numeric feature bits instead.
  292. If in doubt, say Y.
  293. config X86_FAST_FEATURE_TESTS
  294. bool "Fast CPU feature tests" if EMBEDDED
  295. default y
  296. ---help---
  297. Some fast-paths in the kernel depend on the capabilities of the CPU.
  298. Say Y here for the kernel to patch in the appropriate code at runtime
  299. based on the capabilities of the CPU. The infrastructure for patching
  300. code at runtime takes up some additional space; space-constrained
  301. embedded systems may wish to say N here to produce smaller, slightly
  302. slower code.
  303. config X86_X2APIC
  304. bool "Support x2apic"
  305. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  306. ---help---
  307. This enables x2apic support on CPUs that have this feature.
  308. This allows 32-bit apic IDs (so it can support very large systems),
  309. and accesses the local apic via MSRs not via mmio.
  310. If you don't know what to do here, say N.
  311. config X86_MPPARSE
  312. bool "Enable MPS table" if ACPI || SFI
  313. default y
  314. depends on X86_LOCAL_APIC
  315. ---help---
  316. For old smp systems that do not have proper acpi support. Newer systems
  317. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  318. config X86_BIGSMP
  319. bool "Support for big SMP systems with more than 8 CPUs"
  320. depends on X86_32 && SMP
  321. ---help---
  322. This option is needed for the systems that have more than 8 CPUs
  323. config GOLDFISH
  324. def_bool y
  325. depends on X86_GOLDFISH
  326. config RETPOLINE
  327. bool "Avoid speculative indirect branches in kernel"
  328. default y
  329. ---help---
  330. Compile kernel with the retpoline compiler options to guard against
  331. kernel-to-user data leaks by avoiding speculative indirect
  332. branches. Requires a compiler with -mindirect-branch=thunk-extern
  333. support for full protection. The kernel may run slower.
  334. Without compiler support, at least indirect branches in assembler
  335. code are eliminated. Since this includes the syscall entry path,
  336. it is not entirely pointless.
  337. if X86_32
  338. config X86_EXTENDED_PLATFORM
  339. bool "Support for extended (non-PC) x86 platforms"
  340. default y
  341. ---help---
  342. If you disable this option then the kernel will only support
  343. standard PC platforms. (which covers the vast majority of
  344. systems out there.)
  345. If you enable this option then you'll be able to select support
  346. for the following (non-PC) 32 bit x86 platforms:
  347. Goldfish (Android emulator)
  348. AMD Elan
  349. RDC R-321x SoC
  350. SGI 320/540 (Visual Workstation)
  351. STA2X11-based (e.g. Northville)
  352. Moorestown MID devices
  353. If you have one of these systems, or if you want to build a
  354. generic distribution kernel, say Y here - otherwise say N.
  355. endif
  356. if X86_64
  357. config X86_EXTENDED_PLATFORM
  358. bool "Support for extended (non-PC) x86 platforms"
  359. default y
  360. ---help---
  361. If you disable this option then the kernel will only support
  362. standard PC platforms. (which covers the vast majority of
  363. systems out there.)
  364. If you enable this option then you'll be able to select support
  365. for the following (non-PC) 64 bit x86 platforms:
  366. Numascale NumaChip
  367. ScaleMP vSMP
  368. SGI Ultraviolet
  369. If you have one of these systems, or if you want to build a
  370. generic distribution kernel, say Y here - otherwise say N.
  371. endif
  372. # This is an alphabetically sorted list of 64 bit extended platforms
  373. # Please maintain the alphabetic order if and when there are additions
  374. config X86_NUMACHIP
  375. bool "Numascale NumaChip"
  376. depends on X86_64
  377. depends on X86_EXTENDED_PLATFORM
  378. depends on NUMA
  379. depends on SMP
  380. depends on X86_X2APIC
  381. depends on PCI_MMCONFIG
  382. ---help---
  383. Adds support for Numascale NumaChip large-SMP systems. Needed to
  384. enable more than ~168 cores.
  385. If you don't have one of these, you should say N here.
  386. config X86_VSMP
  387. bool "ScaleMP vSMP"
  388. select HYPERVISOR_GUEST
  389. select PARAVIRT
  390. depends on X86_64 && PCI
  391. depends on X86_EXTENDED_PLATFORM
  392. depends on SMP
  393. ---help---
  394. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  395. supposed to run on these EM64T-based machines. Only choose this option
  396. if you have one of these machines.
  397. config X86_UV
  398. bool "SGI Ultraviolet"
  399. depends on X86_64
  400. depends on X86_EXTENDED_PLATFORM
  401. depends on NUMA
  402. depends on X86_X2APIC
  403. depends on PCI
  404. ---help---
  405. This option is needed in order to support SGI Ultraviolet systems.
  406. If you don't have one of these, you should say N here.
  407. # Following is an alphabetically sorted list of 32 bit extended platforms
  408. # Please maintain the alphabetic order if and when there are additions
  409. config X86_GOLDFISH
  410. bool "Goldfish (Virtual Platform)"
  411. depends on X86_EXTENDED_PLATFORM
  412. ---help---
  413. Enable support for the Goldfish virtual platform used primarily
  414. for Android development. Unless you are building for the Android
  415. Goldfish emulator say N here.
  416. config X86_INTEL_CE
  417. bool "CE4100 TV platform"
  418. depends on PCI
  419. depends on PCI_GODIRECT
  420. depends on X86_IO_APIC
  421. depends on X86_32
  422. depends on X86_EXTENDED_PLATFORM
  423. select X86_REBOOTFIXUPS
  424. select OF
  425. select OF_EARLY_FLATTREE
  426. ---help---
  427. Select for the Intel CE media processor (CE4100) SOC.
  428. This option compiles in support for the CE4100 SOC for settop
  429. boxes and media devices.
  430. config X86_INTEL_MID
  431. bool "Intel MID platform support"
  432. depends on X86_32
  433. depends on X86_EXTENDED_PLATFORM
  434. depends on X86_PLATFORM_DEVICES
  435. depends on PCI
  436. depends on PCI_GOANY
  437. depends on X86_IO_APIC
  438. select SFI
  439. select I2C
  440. select DW_APB_TIMER
  441. select APB_TIMER
  442. select INTEL_SCU_IPC
  443. select MFD_INTEL_MSIC
  444. ---help---
  445. Select to build a kernel capable of supporting Intel MID (Mobile
  446. Internet Device) platform systems which do not have the PCI legacy
  447. interfaces. If you are building for a PC class system say N here.
  448. Intel MID platforms are based on an Intel processor and chipset which
  449. consume less power than most of the x86 derivatives.
  450. config X86_INTEL_QUARK
  451. bool "Intel Quark platform support"
  452. depends on X86_32
  453. depends on X86_EXTENDED_PLATFORM
  454. depends on X86_PLATFORM_DEVICES
  455. depends on X86_TSC
  456. depends on PCI
  457. depends on PCI_GOANY
  458. depends on X86_IO_APIC
  459. select IOSF_MBI
  460. select INTEL_IMR
  461. select COMMON_CLK
  462. ---help---
  463. Select to include support for Quark X1000 SoC.
  464. Say Y here if you have a Quark based system such as the Arduino
  465. compatible Intel Galileo.
  466. config X86_INTEL_LPSS
  467. bool "Intel Low Power Subsystem Support"
  468. depends on ACPI
  469. select COMMON_CLK
  470. select PINCTRL
  471. ---help---
  472. Select to build support for Intel Low Power Subsystem such as
  473. found on Intel Lynxpoint PCH. Selecting this option enables
  474. things like clock tree (common clock framework) and pincontrol
  475. which are needed by the LPSS peripheral drivers.
  476. config X86_AMD_PLATFORM_DEVICE
  477. bool "AMD ACPI2Platform devices support"
  478. depends on ACPI
  479. select COMMON_CLK
  480. select PINCTRL
  481. ---help---
  482. Select to interpret AMD specific ACPI device to platform device
  483. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  484. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  485. implemented under PINCTRL subsystem.
  486. config IOSF_MBI
  487. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  488. depends on PCI
  489. ---help---
  490. This option enables sideband register access support for Intel SoC
  491. platforms. On these platforms the IOSF sideband is used in lieu of
  492. MSR's for some register accesses, mostly but not limited to thermal
  493. and power. Drivers may query the availability of this device to
  494. determine if they need the sideband in order to work on these
  495. platforms. The sideband is available on the following SoC products.
  496. This list is not meant to be exclusive.
  497. - BayTrail
  498. - Braswell
  499. - Quark
  500. You should say Y if you are running a kernel on one of these SoC's.
  501. config IOSF_MBI_DEBUG
  502. bool "Enable IOSF sideband access through debugfs"
  503. depends on IOSF_MBI && DEBUG_FS
  504. ---help---
  505. Select this option to expose the IOSF sideband access registers (MCR,
  506. MDR, MCRX) through debugfs to write and read register information from
  507. different units on the SoC. This is most useful for obtaining device
  508. state information for debug and analysis. As this is a general access
  509. mechanism, users of this option would have specific knowledge of the
  510. device they want to access.
  511. If you don't require the option or are in doubt, say N.
  512. config X86_RDC321X
  513. bool "RDC R-321x SoC"
  514. depends on X86_32
  515. depends on X86_EXTENDED_PLATFORM
  516. select M486
  517. select X86_REBOOTFIXUPS
  518. ---help---
  519. This option is needed for RDC R-321x system-on-chip, also known
  520. as R-8610-(G).
  521. If you don't have one of these chips, you should say N here.
  522. config X86_32_NON_STANDARD
  523. bool "Support non-standard 32-bit SMP architectures"
  524. depends on X86_32 && SMP
  525. depends on X86_EXTENDED_PLATFORM
  526. ---help---
  527. This option compiles in the bigsmp and STA2X11 default
  528. subarchitectures. It is intended for a generic binary
  529. kernel. If you select them all, kernel will probe it one by
  530. one and will fallback to default.
  531. # Alphabetically sorted list of Non standard 32 bit platforms
  532. config X86_SUPPORTS_MEMORY_FAILURE
  533. def_bool y
  534. # MCE code calls memory_failure():
  535. depends on X86_MCE
  536. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  537. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  538. depends on X86_64 || !SPARSEMEM
  539. select ARCH_SUPPORTS_MEMORY_FAILURE
  540. config STA2X11
  541. bool "STA2X11 Companion Chip Support"
  542. depends on X86_32_NON_STANDARD && PCI
  543. select X86_DEV_DMA_OPS
  544. select X86_DMA_REMAP
  545. select SWIOTLB
  546. select MFD_STA2X11
  547. select ARCH_REQUIRE_GPIOLIB
  548. default n
  549. ---help---
  550. This adds support for boards based on the STA2X11 IO-Hub,
  551. a.k.a. "ConneXt". The chip is used in place of the standard
  552. PC chipset, so all "standard" peripherals are missing. If this
  553. option is selected the kernel will still be able to boot on
  554. standard PC machines.
  555. config X86_32_IRIS
  556. tristate "Eurobraille/Iris poweroff module"
  557. depends on X86_32
  558. ---help---
  559. The Iris machines from EuroBraille do not have APM or ACPI support
  560. to shut themselves down properly. A special I/O sequence is
  561. needed to do so, which is what this module does at
  562. kernel shutdown.
  563. This is only for Iris machines from EuroBraille.
  564. If unused, say N.
  565. config SCHED_OMIT_FRAME_POINTER
  566. def_bool y
  567. prompt "Single-depth WCHAN output"
  568. depends on X86
  569. ---help---
  570. Calculate simpler /proc/<PID>/wchan values. If this option
  571. is disabled then wchan values will recurse back to the
  572. caller function. This provides more accurate wchan values,
  573. at the expense of slightly more scheduling overhead.
  574. If in doubt, say "Y".
  575. menuconfig HYPERVISOR_GUEST
  576. bool "Linux guest support"
  577. ---help---
  578. Say Y here to enable options for running Linux under various hyper-
  579. visors. This option enables basic hypervisor detection and platform
  580. setup.
  581. If you say N, all options in this submenu will be skipped and
  582. disabled, and Linux guest support won't be built in.
  583. if HYPERVISOR_GUEST
  584. config PARAVIRT
  585. bool "Enable paravirtualization code"
  586. ---help---
  587. This changes the kernel so it can modify itself when it is run
  588. under a hypervisor, potentially improving performance significantly
  589. over full virtualization. However, when run without a hypervisor
  590. the kernel is theoretically slower and slightly larger.
  591. config PARAVIRT_DEBUG
  592. bool "paravirt-ops debugging"
  593. depends on PARAVIRT && DEBUG_KERNEL
  594. ---help---
  595. Enable to debug paravirt_ops internals. Specifically, BUG if
  596. a paravirt_op is missing when it is called.
  597. config PARAVIRT_SPINLOCKS
  598. bool "Paravirtualization layer for spinlocks"
  599. depends on PARAVIRT && SMP
  600. select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
  601. ---help---
  602. Paravirtualized spinlocks allow a pvops backend to replace the
  603. spinlock implementation with something virtualization-friendly
  604. (for example, block the virtual CPU rather than spinning).
  605. It has a minimal impact on native kernels and gives a nice performance
  606. benefit on paravirtualized KVM / Xen kernels.
  607. If you are unsure how to answer this question, answer Y.
  608. source "arch/x86/xen/Kconfig"
  609. config KVM_GUEST
  610. bool "KVM Guest support (including kvmclock)"
  611. depends on PARAVIRT
  612. select PARAVIRT_CLOCK
  613. default y
  614. ---help---
  615. This option enables various optimizations for running under the KVM
  616. hypervisor. It includes a paravirtualized clock, so that instead
  617. of relying on a PIT (or probably other) emulation by the
  618. underlying device model, the host provides the guest with
  619. timing infrastructure such as time of day, and system time
  620. config KVM_DEBUG_FS
  621. bool "Enable debug information for KVM Guests in debugfs"
  622. depends on KVM_GUEST && DEBUG_FS
  623. default n
  624. ---help---
  625. This option enables collection of various statistics for KVM guest.
  626. Statistics are displayed in debugfs filesystem. Enabling this option
  627. may incur significant overhead.
  628. source "arch/x86/lguest/Kconfig"
  629. config PARAVIRT_TIME_ACCOUNTING
  630. bool "Paravirtual steal time accounting"
  631. depends on PARAVIRT
  632. default n
  633. ---help---
  634. Select this option to enable fine granularity task steal time
  635. accounting. Time spent executing other tasks in parallel with
  636. the current vCPU is discounted from the vCPU power. To account for
  637. that, there can be a small performance impact.
  638. If in doubt, say N here.
  639. config PARAVIRT_CLOCK
  640. bool
  641. endif #HYPERVISOR_GUEST
  642. config NO_BOOTMEM
  643. def_bool y
  644. source "arch/x86/Kconfig.cpu"
  645. config HPET_TIMER
  646. def_bool X86_64
  647. prompt "HPET Timer Support" if X86_32
  648. ---help---
  649. Use the IA-PC HPET (High Precision Event Timer) to manage
  650. time in preference to the PIT and RTC, if a HPET is
  651. present.
  652. HPET is the next generation timer replacing legacy 8254s.
  653. The HPET provides a stable time base on SMP
  654. systems, unlike the TSC, but it is more expensive to access,
  655. as it is off-chip. You can find the HPET spec at
  656. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  657. You can safely choose Y here. However, HPET will only be
  658. activated if the platform and the BIOS support this feature.
  659. Otherwise the 8254 will be used for timing services.
  660. Choose N to continue using the legacy 8254 timer.
  661. config HPET_EMULATE_RTC
  662. def_bool y
  663. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  664. config APB_TIMER
  665. def_bool y if X86_INTEL_MID
  666. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  667. select DW_APB_TIMER
  668. depends on X86_INTEL_MID && SFI
  669. help
  670. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  671. The APBT provides a stable time base on SMP
  672. systems, unlike the TSC, but it is more expensive to access,
  673. as it is off-chip. APB timers are always running regardless of CPU
  674. C states, they are used as per CPU clockevent device when possible.
  675. # Mark as expert because too many people got it wrong.
  676. # The code disables itself when not needed.
  677. config DMI
  678. default y
  679. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  680. bool "Enable DMI scanning" if EXPERT
  681. ---help---
  682. Enabled scanning of DMI to identify machine quirks. Say Y
  683. here unless you have verified that your setup is not
  684. affected by entries in the DMI blacklist. Required by PNP
  685. BIOS code.
  686. config GART_IOMMU
  687. bool "Old AMD GART IOMMU support"
  688. select SWIOTLB
  689. depends on X86_64 && PCI && AMD_NB
  690. ---help---
  691. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  692. GART based hardware IOMMUs.
  693. The GART supports full DMA access for devices with 32-bit access
  694. limitations, on systems with more than 3 GB. This is usually needed
  695. for USB, sound, many IDE/SATA chipsets and some other devices.
  696. Newer systems typically have a modern AMD IOMMU, supported via
  697. the CONFIG_AMD_IOMMU=y config option.
  698. In normal configurations this driver is only active when needed:
  699. there's more than 3 GB of memory and the system contains a
  700. 32-bit limited device.
  701. If unsure, say Y.
  702. config CALGARY_IOMMU
  703. bool "IBM Calgary IOMMU support"
  704. select SWIOTLB
  705. depends on X86_64 && PCI
  706. ---help---
  707. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  708. systems. Needed to run systems with more than 3GB of memory
  709. properly with 32-bit PCI devices that do not support DAC
  710. (Double Address Cycle). Calgary also supports bus level
  711. isolation, where all DMAs pass through the IOMMU. This
  712. prevents them from going anywhere except their intended
  713. destination. This catches hard-to-find kernel bugs and
  714. mis-behaving drivers and devices that do not use the DMA-API
  715. properly to set up their DMA buffers. The IOMMU can be
  716. turned off at boot time with the iommu=off parameter.
  717. Normally the kernel will make the right choice by itself.
  718. If unsure, say Y.
  719. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  720. def_bool y
  721. prompt "Should Calgary be enabled by default?"
  722. depends on CALGARY_IOMMU
  723. ---help---
  724. Should Calgary be enabled by default? if you choose 'y', Calgary
  725. will be used (if it exists). If you choose 'n', Calgary will not be
  726. used even if it exists. If you choose 'n' and would like to use
  727. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  728. If unsure, say Y.
  729. # need this always selected by IOMMU for the VIA workaround
  730. config SWIOTLB
  731. def_bool y if X86_64
  732. ---help---
  733. Support for software bounce buffers used on x86-64 systems
  734. which don't have a hardware IOMMU. Using this PCI devices
  735. which can only access 32-bits of memory can be used on systems
  736. with more than 3 GB of memory.
  737. If unsure, say Y.
  738. config IOMMU_HELPER
  739. def_bool y
  740. depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
  741. config MAXSMP
  742. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  743. depends on X86_64 && SMP && DEBUG_KERNEL
  744. select CPUMASK_OFFSTACK
  745. ---help---
  746. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  747. If unsure, say N.
  748. config NR_CPUS
  749. int "Maximum number of CPUs" if SMP && !MAXSMP
  750. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  751. range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
  752. range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
  753. default "1" if !SMP
  754. default "8192" if MAXSMP
  755. default "32" if SMP && X86_BIGSMP
  756. default "8" if SMP && X86_32
  757. default "64" if SMP
  758. ---help---
  759. This allows you to specify the maximum number of CPUs which this
  760. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  761. supported value is 8192, otherwise the maximum value is 512. The
  762. minimum value which makes sense is 2.
  763. This is purely to save memory - each supported CPU adds
  764. approximately eight kilobytes to the kernel image.
  765. config SCHED_SMT
  766. bool "SMT (Hyperthreading) scheduler support"
  767. depends on SMP
  768. ---help---
  769. SMT scheduler support improves the CPU scheduler's decision making
  770. when dealing with Intel Pentium 4 chips with HyperThreading at a
  771. cost of slightly increased overhead in some places. If unsure say
  772. N here.
  773. config SCHED_MC
  774. def_bool y
  775. prompt "Multi-core scheduler support"
  776. depends on SMP
  777. ---help---
  778. Multi-core scheduler support improves the CPU scheduler's decision
  779. making when dealing with multi-core CPU chips at a cost of slightly
  780. increased overhead in some places. If unsure say N here.
  781. source "kernel/Kconfig.preempt"
  782. config UP_LATE_INIT
  783. def_bool y
  784. depends on !SMP && X86_LOCAL_APIC
  785. config X86_UP_APIC
  786. bool "Local APIC support on uniprocessors" if !PCI_MSI
  787. default PCI_MSI
  788. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  789. ---help---
  790. A local APIC (Advanced Programmable Interrupt Controller) is an
  791. integrated interrupt controller in the CPU. If you have a single-CPU
  792. system which has a processor with a local APIC, you can say Y here to
  793. enable and use it. If you say Y here even though your machine doesn't
  794. have a local APIC, then the kernel will still run with no slowdown at
  795. all. The local APIC supports CPU-generated self-interrupts (timer,
  796. performance counters), and the NMI watchdog which detects hard
  797. lockups.
  798. config X86_UP_IOAPIC
  799. bool "IO-APIC support on uniprocessors"
  800. depends on X86_UP_APIC
  801. ---help---
  802. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  803. SMP-capable replacement for PC-style interrupt controllers. Most
  804. SMP systems and many recent uniprocessor systems have one.
  805. If you have a single-CPU system with an IO-APIC, you can say Y here
  806. to use it. If you say Y here even though your machine doesn't have
  807. an IO-APIC, then the kernel will still run with no slowdown at all.
  808. config X86_LOCAL_APIC
  809. def_bool y
  810. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  811. select IRQ_DOMAIN_HIERARCHY
  812. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  813. config X86_IO_APIC
  814. def_bool y
  815. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  816. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  817. bool "Reroute for broken boot IRQs"
  818. depends on X86_IO_APIC
  819. ---help---
  820. This option enables a workaround that fixes a source of
  821. spurious interrupts. This is recommended when threaded
  822. interrupt handling is used on systems where the generation of
  823. superfluous "boot interrupts" cannot be disabled.
  824. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  825. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  826. kernel does during interrupt handling). On chipsets where this
  827. boot IRQ generation cannot be disabled, this workaround keeps
  828. the original IRQ line masked so that only the equivalent "boot
  829. IRQ" is delivered to the CPUs. The workaround also tells the
  830. kernel to set up the IRQ handler on the boot IRQ line. In this
  831. way only one interrupt is delivered to the kernel. Otherwise
  832. the spurious second interrupt may cause the kernel to bring
  833. down (vital) interrupt lines.
  834. Only affects "broken" chipsets. Interrupt sharing may be
  835. increased on these systems.
  836. config X86_MCE
  837. bool "Machine Check / overheating reporting"
  838. select GENERIC_ALLOCATOR
  839. default y
  840. ---help---
  841. Machine Check support allows the processor to notify the
  842. kernel if it detects a problem (e.g. overheating, data corruption).
  843. The action the kernel takes depends on the severity of the problem,
  844. ranging from warning messages to halting the machine.
  845. config X86_MCE_INTEL
  846. def_bool y
  847. prompt "Intel MCE features"
  848. depends on X86_MCE && X86_LOCAL_APIC
  849. ---help---
  850. Additional support for intel specific MCE features such as
  851. the thermal monitor.
  852. config X86_MCE_AMD
  853. def_bool y
  854. prompt "AMD MCE features"
  855. depends on X86_MCE && X86_LOCAL_APIC
  856. ---help---
  857. Additional support for AMD specific MCE features such as
  858. the DRAM Error Threshold.
  859. config X86_ANCIENT_MCE
  860. bool "Support for old Pentium 5 / WinChip machine checks"
  861. depends on X86_32 && X86_MCE
  862. ---help---
  863. Include support for machine check handling on old Pentium 5 or WinChip
  864. systems. These typically need to be enabled explicitly on the command
  865. line.
  866. config X86_MCE_THRESHOLD
  867. depends on X86_MCE_AMD || X86_MCE_INTEL
  868. def_bool y
  869. config X86_MCE_INJECT
  870. depends on X86_MCE && X86_LOCAL_APIC
  871. tristate "Machine check injector support"
  872. ---help---
  873. Provide support for injecting machine checks for testing purposes.
  874. If you don't know what a machine check is and you don't do kernel
  875. QA it is safe to say n.
  876. config X86_THERMAL_VECTOR
  877. def_bool y
  878. depends on X86_MCE_INTEL
  879. config X86_LEGACY_VM86
  880. bool "Legacy VM86 support"
  881. default n
  882. depends on X86_32
  883. ---help---
  884. This option allows user programs to put the CPU into V8086
  885. mode, which is an 80286-era approximation of 16-bit real mode.
  886. Some very old versions of X and/or vbetool require this option
  887. for user mode setting. Similarly, DOSEMU will use it if
  888. available to accelerate real mode DOS programs. However, any
  889. recent version of DOSEMU, X, or vbetool should be fully
  890. functional even without kernel VM86 support, as they will all
  891. fall back to software emulation. Nevertheless, if you are using
  892. a 16-bit DOS program where 16-bit performance matters, vm86
  893. mode might be faster than emulation and you might want to
  894. enable this option.
  895. Note that any app that works on a 64-bit kernel is unlikely to
  896. need this option, as 64-bit kernels don't, and can't, support
  897. V8086 mode. This option is also unrelated to 16-bit protected
  898. mode and is not needed to run most 16-bit programs under Wine.
  899. Enabling this option increases the complexity of the kernel
  900. and slows down exception handling a tiny bit.
  901. If unsure, say N here.
  902. config VM86
  903. bool
  904. default X86_LEGACY_VM86
  905. config X86_16BIT
  906. bool "Enable support for 16-bit segments" if EXPERT
  907. default y
  908. depends on MODIFY_LDT_SYSCALL
  909. ---help---
  910. This option is required by programs like Wine to run 16-bit
  911. protected mode legacy code on x86 processors. Disabling
  912. this option saves about 300 bytes on i386, or around 6K text
  913. plus 16K runtime memory on x86-64,
  914. config X86_ESPFIX32
  915. def_bool y
  916. depends on X86_16BIT && X86_32
  917. config X86_ESPFIX64
  918. def_bool y
  919. depends on X86_16BIT && X86_64
  920. config X86_VSYSCALL_EMULATION
  921. bool "Enable vsyscall emulation" if EXPERT
  922. default y
  923. depends on X86_64
  924. ---help---
  925. This enables emulation of the legacy vsyscall page. Disabling
  926. it is roughly equivalent to booting with vsyscall=none, except
  927. that it will also disable the helpful warning if a program
  928. tries to use a vsyscall. With this option set to N, offending
  929. programs will just segfault, citing addresses of the form
  930. 0xffffffffff600?00.
  931. This option is required by many programs built before 2013, and
  932. care should be used even with newer programs if set to N.
  933. Disabling this option saves about 7K of kernel size and
  934. possibly 4K of additional runtime pagetable memory.
  935. config TOSHIBA
  936. tristate "Toshiba Laptop support"
  937. depends on X86_32
  938. ---help---
  939. This adds a driver to safely access the System Management Mode of
  940. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  941. not work on models with a Phoenix BIOS. The System Management Mode
  942. is used to set the BIOS and power saving options on Toshiba portables.
  943. For information on utilities to make use of this driver see the
  944. Toshiba Linux utilities web site at:
  945. <http://www.buzzard.org.uk/toshiba/>.
  946. Say Y if you intend to run this kernel on a Toshiba portable.
  947. Say N otherwise.
  948. config I8K
  949. tristate "Dell i8k legacy laptop support"
  950. select HWMON
  951. select SENSORS_DELL_SMM
  952. ---help---
  953. This option enables legacy /proc/i8k userspace interface in hwmon
  954. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  955. temperature and allows controlling fan speeds of Dell laptops via
  956. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  957. it reports also power and hotkey status. For fan speed control is
  958. needed userspace package i8kutils.
  959. Say Y if you intend to run this kernel on old Dell laptops or want to
  960. use userspace package i8kutils.
  961. Say N otherwise.
  962. config X86_REBOOTFIXUPS
  963. bool "Enable X86 board specific fixups for reboot"
  964. depends on X86_32
  965. ---help---
  966. This enables chipset and/or board specific fixups to be done
  967. in order to get reboot to work correctly. This is only needed on
  968. some combinations of hardware and BIOS. The symptom, for which
  969. this config is intended, is when reboot ends with a stalled/hung
  970. system.
  971. Currently, the only fixup is for the Geode machines using
  972. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  973. Say Y if you want to enable the fixup. Currently, it's safe to
  974. enable this option even if you don't need it.
  975. Say N otherwise.
  976. config MICROCODE
  977. bool "CPU microcode loading support"
  978. default y
  979. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  980. select FW_LOADER
  981. ---help---
  982. If you say Y here, you will be able to update the microcode on
  983. Intel and AMD processors. The Intel support is for the IA32 family,
  984. e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
  985. AMD support is for families 0x10 and later. You will obviously need
  986. the actual microcode binary data itself which is not shipped with
  987. the Linux kernel.
  988. The preferred method to load microcode from a detached initrd is described
  989. in Documentation/x86/early-microcode.txt. For that you need to enable
  990. CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
  991. initrd for microcode blobs.
  992. In addition, you can build-in the microcode into the kernel. For that you
  993. need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
  994. to the CONFIG_EXTRA_FIRMWARE config option.
  995. config MICROCODE_INTEL
  996. bool "Intel microcode loading support"
  997. depends on MICROCODE
  998. default MICROCODE
  999. select FW_LOADER
  1000. ---help---
  1001. This options enables microcode patch loading support for Intel
  1002. processors.
  1003. For the current Intel microcode data package go to
  1004. <https://downloadcenter.intel.com> and search for
  1005. 'Linux Processor Microcode Data File'.
  1006. config MICROCODE_AMD
  1007. bool "AMD microcode loading support"
  1008. depends on MICROCODE
  1009. select FW_LOADER
  1010. ---help---
  1011. If you select this option, microcode patch loading support for AMD
  1012. processors will be enabled.
  1013. config MICROCODE_OLD_INTERFACE
  1014. def_bool y
  1015. depends on MICROCODE
  1016. config X86_MSR
  1017. tristate "/dev/cpu/*/msr - Model-specific register support"
  1018. ---help---
  1019. This device gives privileged processes access to the x86
  1020. Model-Specific Registers (MSRs). It is a character device with
  1021. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1022. MSR accesses are directed to a specific CPU on multi-processor
  1023. systems.
  1024. config X86_CPUID
  1025. tristate "/dev/cpu/*/cpuid - CPU information support"
  1026. ---help---
  1027. This device gives processes access to the x86 CPUID instruction to
  1028. be executed on a specific processor. It is a character device
  1029. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1030. /dev/cpu/31/cpuid.
  1031. choice
  1032. prompt "High Memory Support"
  1033. default HIGHMEM4G
  1034. depends on X86_32
  1035. config NOHIGHMEM
  1036. bool "off"
  1037. ---help---
  1038. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1039. However, the address space of 32-bit x86 processors is only 4
  1040. Gigabytes large. That means that, if you have a large amount of
  1041. physical memory, not all of it can be "permanently mapped" by the
  1042. kernel. The physical memory that's not permanently mapped is called
  1043. "high memory".
  1044. If you are compiling a kernel which will never run on a machine with
  1045. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1046. choice and suitable for most users). This will result in a "3GB/1GB"
  1047. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1048. space and the remaining part of the 4GB virtual memory space is used
  1049. by the kernel to permanently map as much physical memory as
  1050. possible.
  1051. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1052. answer "4GB" here.
  1053. If more than 4 Gigabytes is used then answer "64GB" here. This
  1054. selection turns Intel PAE (Physical Address Extension) mode on.
  1055. PAE implements 3-level paging on IA32 processors. PAE is fully
  1056. supported by Linux, PAE mode is implemented on all recent Intel
  1057. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1058. then the kernel will not boot on CPUs that don't support PAE!
  1059. The actual amount of total physical memory will either be
  1060. auto detected or can be forced by using a kernel command line option
  1061. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1062. your boot loader (lilo or loadlin) about how to pass options to the
  1063. kernel at boot time.)
  1064. If unsure, say "off".
  1065. config HIGHMEM4G
  1066. bool "4GB"
  1067. ---help---
  1068. Select this if you have a 32-bit processor and between 1 and 4
  1069. gigabytes of physical RAM.
  1070. config HIGHMEM64G
  1071. bool "64GB"
  1072. depends on !M486
  1073. select X86_PAE
  1074. ---help---
  1075. Select this if you have a 32-bit processor and more than 4
  1076. gigabytes of physical RAM.
  1077. endchoice
  1078. choice
  1079. prompt "Memory split" if EXPERT
  1080. default VMSPLIT_3G
  1081. depends on X86_32
  1082. ---help---
  1083. Select the desired split between kernel and user memory.
  1084. If the address range available to the kernel is less than the
  1085. physical memory installed, the remaining memory will be available
  1086. as "high memory". Accessing high memory is a little more costly
  1087. than low memory, as it needs to be mapped into the kernel first.
  1088. Note that increasing the kernel address space limits the range
  1089. available to user programs, making the address space there
  1090. tighter. Selecting anything other than the default 3G/1G split
  1091. will also likely make your kernel incompatible with binary-only
  1092. kernel modules.
  1093. If you are not absolutely sure what you are doing, leave this
  1094. option alone!
  1095. config VMSPLIT_3G
  1096. bool "3G/1G user/kernel split"
  1097. config VMSPLIT_3G_OPT
  1098. depends on !X86_PAE
  1099. bool "3G/1G user/kernel split (for full 1G low memory)"
  1100. config VMSPLIT_2G
  1101. bool "2G/2G user/kernel split"
  1102. config VMSPLIT_2G_OPT
  1103. depends on !X86_PAE
  1104. bool "2G/2G user/kernel split (for full 2G low memory)"
  1105. config VMSPLIT_1G
  1106. bool "1G/3G user/kernel split"
  1107. endchoice
  1108. config PAGE_OFFSET
  1109. hex
  1110. default 0xB0000000 if VMSPLIT_3G_OPT
  1111. default 0x80000000 if VMSPLIT_2G
  1112. default 0x78000000 if VMSPLIT_2G_OPT
  1113. default 0x40000000 if VMSPLIT_1G
  1114. default 0xC0000000
  1115. depends on X86_32
  1116. config HIGHMEM
  1117. def_bool y
  1118. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1119. config X86_PAE
  1120. bool "PAE (Physical Address Extension) Support"
  1121. depends on X86_32 && !HIGHMEM4G
  1122. select SWIOTLB
  1123. ---help---
  1124. PAE is required for NX support, and furthermore enables
  1125. larger swapspace support for non-overcommit purposes. It
  1126. has the cost of more pagetable lookup overhead, and also
  1127. consumes more pagetable space per process.
  1128. config ARCH_PHYS_ADDR_T_64BIT
  1129. def_bool y
  1130. depends on X86_64 || X86_PAE
  1131. config ARCH_DMA_ADDR_T_64BIT
  1132. def_bool y
  1133. depends on X86_64 || HIGHMEM64G
  1134. config X86_DIRECT_GBPAGES
  1135. def_bool y
  1136. depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
  1137. ---help---
  1138. Certain kernel features effectively disable kernel
  1139. linear 1 GB mappings (even if the CPU otherwise
  1140. supports them), so don't confuse the user by printing
  1141. that we have them enabled.
  1142. # Common NUMA Features
  1143. config NUMA
  1144. bool "Numa Memory Allocation and Scheduler Support"
  1145. depends on SMP
  1146. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1147. default y if X86_BIGSMP
  1148. ---help---
  1149. Enable NUMA (Non Uniform Memory Access) support.
  1150. The kernel will try to allocate memory used by a CPU on the
  1151. local memory controller of the CPU and add some more
  1152. NUMA awareness to the kernel.
  1153. For 64-bit this is recommended if the system is Intel Core i7
  1154. (or later), AMD Opteron, or EM64T NUMA.
  1155. For 32-bit this is only needed if you boot a 32-bit
  1156. kernel on a 64-bit NUMA platform.
  1157. Otherwise, you should say N.
  1158. config AMD_NUMA
  1159. def_bool y
  1160. prompt "Old style AMD Opteron NUMA detection"
  1161. depends on X86_64 && NUMA && PCI
  1162. ---help---
  1163. Enable AMD NUMA node topology detection. You should say Y here if
  1164. you have a multi processor AMD system. This uses an old method to
  1165. read the NUMA configuration directly from the builtin Northbridge
  1166. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1167. which also takes priority if both are compiled in.
  1168. config X86_64_ACPI_NUMA
  1169. def_bool y
  1170. prompt "ACPI NUMA detection"
  1171. depends on X86_64 && NUMA && ACPI && PCI
  1172. select ACPI_NUMA
  1173. ---help---
  1174. Enable ACPI SRAT based node topology detection.
  1175. # Some NUMA nodes have memory ranges that span
  1176. # other nodes. Even though a pfn is valid and
  1177. # between a node's start and end pfns, it may not
  1178. # reside on that node. See memmap_init_zone()
  1179. # for details.
  1180. config NODES_SPAN_OTHER_NODES
  1181. def_bool y
  1182. depends on X86_64_ACPI_NUMA
  1183. config NUMA_EMU
  1184. bool "NUMA emulation"
  1185. depends on NUMA
  1186. ---help---
  1187. Enable NUMA emulation. A flat machine will be split
  1188. into virtual nodes when booted with "numa=fake=N", where N is the
  1189. number of nodes. This is only useful for debugging.
  1190. config NODES_SHIFT
  1191. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1192. range 1 10
  1193. default "10" if MAXSMP
  1194. default "6" if X86_64
  1195. default "3"
  1196. depends on NEED_MULTIPLE_NODES
  1197. ---help---
  1198. Specify the maximum number of NUMA Nodes available on the target
  1199. system. Increases memory reserved to accommodate various tables.
  1200. config ARCH_HAVE_MEMORY_PRESENT
  1201. def_bool y
  1202. depends on X86_32 && DISCONTIGMEM
  1203. config NEED_NODE_MEMMAP_SIZE
  1204. def_bool y
  1205. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1206. config ARCH_FLATMEM_ENABLE
  1207. def_bool y
  1208. depends on X86_32 && !NUMA
  1209. config ARCH_DISCONTIGMEM_ENABLE
  1210. def_bool y
  1211. depends on NUMA && X86_32
  1212. config ARCH_DISCONTIGMEM_DEFAULT
  1213. def_bool y
  1214. depends on NUMA && X86_32
  1215. config ARCH_SPARSEMEM_ENABLE
  1216. def_bool y
  1217. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1218. select SPARSEMEM_STATIC if X86_32
  1219. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1220. config ARCH_SPARSEMEM_DEFAULT
  1221. def_bool y
  1222. depends on X86_64
  1223. config ARCH_SELECT_MEMORY_MODEL
  1224. def_bool y
  1225. depends on ARCH_SPARSEMEM_ENABLE
  1226. config ARCH_MEMORY_PROBE
  1227. bool "Enable sysfs memory/probe interface"
  1228. depends on X86_64 && MEMORY_HOTPLUG
  1229. help
  1230. This option enables a sysfs memory/probe interface for testing.
  1231. See Documentation/memory-hotplug.txt for more information.
  1232. If you are unsure how to answer this question, answer N.
  1233. config ARCH_PROC_KCORE_TEXT
  1234. def_bool y
  1235. depends on X86_64 && PROC_KCORE
  1236. config ILLEGAL_POINTER_VALUE
  1237. hex
  1238. default 0 if X86_32
  1239. default 0xdead000000000000 if X86_64
  1240. source "mm/Kconfig"
  1241. config X86_PMEM_LEGACY_DEVICE
  1242. bool
  1243. config X86_PMEM_LEGACY
  1244. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1245. depends on PHYS_ADDR_T_64BIT
  1246. depends on BLK_DEV
  1247. select X86_PMEM_LEGACY_DEVICE
  1248. select LIBNVDIMM
  1249. help
  1250. Treat memory marked using the non-standard e820 type of 12 as used
  1251. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1252. The kernel will offer these regions to the 'pmem' driver so
  1253. they can be used for persistent storage.
  1254. Say Y if unsure.
  1255. config HIGHPTE
  1256. bool "Allocate 3rd-level pagetables from highmem"
  1257. depends on HIGHMEM
  1258. ---help---
  1259. The VM uses one page table entry for each page of physical memory.
  1260. For systems with a lot of RAM, this can be wasteful of precious
  1261. low memory. Setting this option will put user-space page table
  1262. entries in high memory.
  1263. config X86_CHECK_BIOS_CORRUPTION
  1264. bool "Check for low memory corruption"
  1265. ---help---
  1266. Periodically check for memory corruption in low memory, which
  1267. is suspected to be caused by BIOS. Even when enabled in the
  1268. configuration, it is disabled at runtime. Enable it by
  1269. setting "memory_corruption_check=1" on the kernel command
  1270. line. By default it scans the low 64k of memory every 60
  1271. seconds; see the memory_corruption_check_size and
  1272. memory_corruption_check_period parameters in
  1273. Documentation/kernel-parameters.txt to adjust this.
  1274. When enabled with the default parameters, this option has
  1275. almost no overhead, as it reserves a relatively small amount
  1276. of memory and scans it infrequently. It both detects corruption
  1277. and prevents it from affecting the running system.
  1278. It is, however, intended as a diagnostic tool; if repeatable
  1279. BIOS-originated corruption always affects the same memory,
  1280. you can use memmap= to prevent the kernel from using that
  1281. memory.
  1282. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1283. bool "Set the default setting of memory_corruption_check"
  1284. depends on X86_CHECK_BIOS_CORRUPTION
  1285. default y
  1286. ---help---
  1287. Set whether the default state of memory_corruption_check is
  1288. on or off.
  1289. config X86_RESERVE_LOW
  1290. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1291. default 64
  1292. range 4 640
  1293. ---help---
  1294. Specify the amount of low memory to reserve for the BIOS.
  1295. The first page contains BIOS data structures that the kernel
  1296. must not use, so that page must always be reserved.
  1297. By default we reserve the first 64K of physical RAM, as a
  1298. number of BIOSes are known to corrupt that memory range
  1299. during events such as suspend/resume or monitor cable
  1300. insertion, so it must not be used by the kernel.
  1301. You can set this to 4 if you are absolutely sure that you
  1302. trust the BIOS to get all its memory reservations and usages
  1303. right. If you know your BIOS have problems beyond the
  1304. default 64K area, you can set this to 640 to avoid using the
  1305. entire low memory range.
  1306. If you have doubts about the BIOS (e.g. suspend/resume does
  1307. not work or there's kernel crashes after certain hardware
  1308. hotplug events) then you might want to enable
  1309. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1310. typical corruption patterns.
  1311. Leave this to the default value of 64 if you are unsure.
  1312. config MATH_EMULATION
  1313. bool
  1314. depends on MODIFY_LDT_SYSCALL
  1315. prompt "Math emulation" if X86_32
  1316. ---help---
  1317. Linux can emulate a math coprocessor (used for floating point
  1318. operations) if you don't have one. 486DX and Pentium processors have
  1319. a math coprocessor built in, 486SX and 386 do not, unless you added
  1320. a 487DX or 387, respectively. (The messages during boot time can
  1321. give you some hints here ["man dmesg"].) Everyone needs either a
  1322. coprocessor or this emulation.
  1323. If you don't have a math coprocessor, you need to say Y here; if you
  1324. say Y here even though you have a coprocessor, the coprocessor will
  1325. be used nevertheless. (This behavior can be changed with the kernel
  1326. command line option "no387", which comes handy if your coprocessor
  1327. is broken. Try "man bootparam" or see the documentation of your boot
  1328. loader (lilo or loadlin) about how to pass options to the kernel at
  1329. boot time.) This means that it is a good idea to say Y here if you
  1330. intend to use this kernel on different machines.
  1331. More information about the internals of the Linux math coprocessor
  1332. emulation can be found in <file:arch/x86/math-emu/README>.
  1333. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1334. kernel, it won't hurt.
  1335. config MTRR
  1336. def_bool y
  1337. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1338. ---help---
  1339. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1340. the Memory Type Range Registers (MTRRs) may be used to control
  1341. processor access to memory ranges. This is most useful if you have
  1342. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1343. allows bus write transfers to be combined into a larger transfer
  1344. before bursting over the PCI/AGP bus. This can increase performance
  1345. of image write operations 2.5 times or more. Saying Y here creates a
  1346. /proc/mtrr file which may be used to manipulate your processor's
  1347. MTRRs. Typically the X server should use this.
  1348. This code has a reasonably generic interface so that similar
  1349. control registers on other processors can be easily supported
  1350. as well:
  1351. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1352. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1353. these, the ARRs are used to emulate the MTRRs.
  1354. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1355. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1356. write-combining. All of these processors are supported by this code
  1357. and it makes sense to say Y here if you have one of them.
  1358. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1359. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1360. can lead to all sorts of problems, so it's good to say Y here.
  1361. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1362. just add about 9 KB to your kernel.
  1363. See <file:Documentation/x86/mtrr.txt> for more information.
  1364. config MTRR_SANITIZER
  1365. def_bool y
  1366. prompt "MTRR cleanup support"
  1367. depends on MTRR
  1368. ---help---
  1369. Convert MTRR layout from continuous to discrete, so X drivers can
  1370. add writeback entries.
  1371. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1372. The largest mtrr entry size for a continuous block can be set with
  1373. mtrr_chunk_size.
  1374. If unsure, say Y.
  1375. config MTRR_SANITIZER_ENABLE_DEFAULT
  1376. int "MTRR cleanup enable value (0-1)"
  1377. range 0 1
  1378. default "0"
  1379. depends on MTRR_SANITIZER
  1380. ---help---
  1381. Enable mtrr cleanup default value
  1382. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1383. int "MTRR cleanup spare reg num (0-7)"
  1384. range 0 7
  1385. default "1"
  1386. depends on MTRR_SANITIZER
  1387. ---help---
  1388. mtrr cleanup spare entries default, it can be changed via
  1389. mtrr_spare_reg_nr=N on the kernel command line.
  1390. config X86_PAT
  1391. def_bool y
  1392. prompt "x86 PAT support" if EXPERT
  1393. depends on MTRR
  1394. ---help---
  1395. Use PAT attributes to setup page level cache control.
  1396. PATs are the modern equivalents of MTRRs and are much more
  1397. flexible than MTRRs.
  1398. Say N here if you see bootup problems (boot crash, boot hang,
  1399. spontaneous reboots) or a non-working video driver.
  1400. If unsure, say Y.
  1401. config ARCH_USES_PG_UNCACHED
  1402. def_bool y
  1403. depends on X86_PAT
  1404. config ARCH_RANDOM
  1405. def_bool y
  1406. prompt "x86 architectural random number generator" if EXPERT
  1407. ---help---
  1408. Enable the x86 architectural RDRAND instruction
  1409. (Intel Bull Mountain technology) to generate random numbers.
  1410. If supported, this is a high bandwidth, cryptographically
  1411. secure hardware random number generator.
  1412. config X86_SMAP
  1413. def_bool y
  1414. prompt "Supervisor Mode Access Prevention" if EXPERT
  1415. ---help---
  1416. Supervisor Mode Access Prevention (SMAP) is a security
  1417. feature in newer Intel processors. There is a small
  1418. performance cost if this enabled and turned on; there is
  1419. also a small increase in the kernel size if this is enabled.
  1420. If unsure, say Y.
  1421. config X86_INTEL_MPX
  1422. prompt "Intel MPX (Memory Protection Extensions)"
  1423. def_bool n
  1424. depends on CPU_SUP_INTEL
  1425. ---help---
  1426. MPX provides hardware features that can be used in
  1427. conjunction with compiler-instrumented code to check
  1428. memory references. It is designed to detect buffer
  1429. overflow or underflow bugs.
  1430. This option enables running applications which are
  1431. instrumented or otherwise use MPX. It does not use MPX
  1432. itself inside the kernel or to protect the kernel
  1433. against bad memory references.
  1434. Enabling this option will make the kernel larger:
  1435. ~8k of kernel text and 36 bytes of data on a 64-bit
  1436. defconfig. It adds a long to the 'mm_struct' which
  1437. will increase the kernel memory overhead of each
  1438. process and adds some branches to paths used during
  1439. exec() and munmap().
  1440. For details, see Documentation/x86/intel_mpx.txt
  1441. If unsure, say N.
  1442. config EFI
  1443. bool "EFI runtime service support"
  1444. depends on ACPI
  1445. select UCS2_STRING
  1446. select EFI_RUNTIME_WRAPPERS
  1447. ---help---
  1448. This enables the kernel to use EFI runtime services that are
  1449. available (such as the EFI variable services).
  1450. This option is only useful on systems that have EFI firmware.
  1451. In addition, you should use the latest ELILO loader available
  1452. at <http://elilo.sourceforge.net> in order to take advantage
  1453. of EFI runtime services. However, even with this option, the
  1454. resultant kernel should continue to boot on existing non-EFI
  1455. platforms.
  1456. config EFI_STUB
  1457. bool "EFI stub support"
  1458. depends on EFI && !X86_USE_3DNOW
  1459. select RELOCATABLE
  1460. ---help---
  1461. This kernel feature allows a bzImage to be loaded directly
  1462. by EFI firmware without the use of a bootloader.
  1463. See Documentation/efi-stub.txt for more information.
  1464. config EFI_MIXED
  1465. bool "EFI mixed-mode support"
  1466. depends on EFI_STUB && X86_64
  1467. ---help---
  1468. Enabling this feature allows a 64-bit kernel to be booted
  1469. on a 32-bit firmware, provided that your CPU supports 64-bit
  1470. mode.
  1471. Note that it is not possible to boot a mixed-mode enabled
  1472. kernel via the EFI boot stub - a bootloader that supports
  1473. the EFI handover protocol must be used.
  1474. If unsure, say N.
  1475. config SECCOMP
  1476. def_bool y
  1477. prompt "Enable seccomp to safely compute untrusted bytecode"
  1478. ---help---
  1479. This kernel feature is useful for number crunching applications
  1480. that may need to compute untrusted bytecode during their
  1481. execution. By using pipes or other transports made available to
  1482. the process as file descriptors supporting the read/write
  1483. syscalls, it's possible to isolate those applications in
  1484. their own address space using seccomp. Once seccomp is
  1485. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1486. and the task is only allowed to execute a few safe syscalls
  1487. defined by each seccomp mode.
  1488. If unsure, say Y. Only embedded should say N here.
  1489. source kernel/Kconfig.hz
  1490. config KEXEC
  1491. bool "kexec system call"
  1492. select KEXEC_CORE
  1493. ---help---
  1494. kexec is a system call that implements the ability to shutdown your
  1495. current kernel, and to start another kernel. It is like a reboot
  1496. but it is independent of the system firmware. And like a reboot
  1497. you can start any kernel with it, not just Linux.
  1498. The name comes from the similarity to the exec system call.
  1499. It is an ongoing process to be certain the hardware in a machine
  1500. is properly shutdown, so do not be surprised if this code does not
  1501. initially work for you. As of this writing the exact hardware
  1502. interface is strongly in flux, so no good recommendation can be
  1503. made.
  1504. config KEXEC_FILE
  1505. bool "kexec file based system call"
  1506. select KEXEC_CORE
  1507. select BUILD_BIN2C
  1508. depends on X86_64
  1509. depends on CRYPTO=y
  1510. depends on CRYPTO_SHA256=y
  1511. ---help---
  1512. This is new version of kexec system call. This system call is
  1513. file based and takes file descriptors as system call argument
  1514. for kernel and initramfs as opposed to list of segments as
  1515. accepted by previous system call.
  1516. config KEXEC_VERIFY_SIG
  1517. bool "Verify kernel signature during kexec_file_load() syscall"
  1518. depends on KEXEC_FILE
  1519. ---help---
  1520. This option makes kernel signature verification mandatory for
  1521. the kexec_file_load() syscall.
  1522. In addition to that option, you need to enable signature
  1523. verification for the corresponding kernel image type being
  1524. loaded in order for this to work.
  1525. config KEXEC_BZIMAGE_VERIFY_SIG
  1526. bool "Enable bzImage signature verification support"
  1527. depends on KEXEC_VERIFY_SIG
  1528. depends on SIGNED_PE_FILE_VERIFICATION
  1529. select SYSTEM_TRUSTED_KEYRING
  1530. ---help---
  1531. Enable bzImage signature verification support.
  1532. config CRASH_DUMP
  1533. bool "kernel crash dumps"
  1534. depends on X86_64 || (X86_32 && HIGHMEM)
  1535. ---help---
  1536. Generate crash dump after being started by kexec.
  1537. This should be normally only set in special crash dump kernels
  1538. which are loaded in the main kernel with kexec-tools into
  1539. a specially reserved region and then later executed after
  1540. a crash by kdump/kexec. The crash dump kernel must be compiled
  1541. to a memory address not used by the main kernel or BIOS using
  1542. PHYSICAL_START, or it must be built as a relocatable image
  1543. (CONFIG_RELOCATABLE=y).
  1544. For more details see Documentation/kdump/kdump.txt
  1545. config KEXEC_JUMP
  1546. bool "kexec jump"
  1547. depends on KEXEC && HIBERNATION
  1548. ---help---
  1549. Jump between original kernel and kexeced kernel and invoke
  1550. code in physical address mode via KEXEC
  1551. config PHYSICAL_START
  1552. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1553. default "0x1000000"
  1554. ---help---
  1555. This gives the physical address where the kernel is loaded.
  1556. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1557. bzImage will decompress itself to above physical address and
  1558. run from there. Otherwise, bzImage will run from the address where
  1559. it has been loaded by the boot loader and will ignore above physical
  1560. address.
  1561. In normal kdump cases one does not have to set/change this option
  1562. as now bzImage can be compiled as a completely relocatable image
  1563. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1564. address. This option is mainly useful for the folks who don't want
  1565. to use a bzImage for capturing the crash dump and want to use a
  1566. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1567. to be specifically compiled to run from a specific memory area
  1568. (normally a reserved region) and this option comes handy.
  1569. So if you are using bzImage for capturing the crash dump,
  1570. leave the value here unchanged to 0x1000000 and set
  1571. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1572. for capturing the crash dump change this value to start of
  1573. the reserved region. In other words, it can be set based on
  1574. the "X" value as specified in the "crashkernel=YM@XM"
  1575. command line boot parameter passed to the panic-ed
  1576. kernel. Please take a look at Documentation/kdump/kdump.txt
  1577. for more details about crash dumps.
  1578. Usage of bzImage for capturing the crash dump is recommended as
  1579. one does not have to build two kernels. Same kernel can be used
  1580. as production kernel and capture kernel. Above option should have
  1581. gone away after relocatable bzImage support is introduced. But it
  1582. is present because there are users out there who continue to use
  1583. vmlinux for dump capture. This option should go away down the
  1584. line.
  1585. Don't change this unless you know what you are doing.
  1586. config RELOCATABLE
  1587. bool "Build a relocatable kernel"
  1588. default y
  1589. ---help---
  1590. This builds a kernel image that retains relocation information
  1591. so it can be loaded someplace besides the default 1MB.
  1592. The relocations tend to make the kernel binary about 10% larger,
  1593. but are discarded at runtime.
  1594. One use is for the kexec on panic case where the recovery kernel
  1595. must live at a different physical address than the primary
  1596. kernel.
  1597. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1598. it has been loaded at and the compile time physical address
  1599. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1600. config RANDOMIZE_BASE
  1601. bool "Randomize the address of the kernel image"
  1602. depends on RELOCATABLE
  1603. default n
  1604. ---help---
  1605. Randomizes the physical and virtual address at which the
  1606. kernel image is decompressed, as a security feature that
  1607. deters exploit attempts relying on knowledge of the location
  1608. of kernel internals.
  1609. Entropy is generated using the RDRAND instruction if it is
  1610. supported. If RDTSC is supported, it is used as well. If
  1611. neither RDRAND nor RDTSC are supported, then randomness is
  1612. read from the i8254 timer.
  1613. The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
  1614. and aligned according to PHYSICAL_ALIGN. Since the kernel is
  1615. built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
  1616. minimum of 2MiB, only 10 bits of entropy is theoretically
  1617. possible. At best, due to page table layouts, 64-bit can use
  1618. 9 bits of entropy and 32-bit uses 8 bits.
  1619. If unsure, say N.
  1620. config RANDOMIZE_BASE_MAX_OFFSET
  1621. hex "Maximum kASLR offset allowed" if EXPERT
  1622. depends on RANDOMIZE_BASE
  1623. range 0x0 0x20000000 if X86_32
  1624. default "0x20000000" if X86_32
  1625. range 0x0 0x40000000 if X86_64
  1626. default "0x40000000" if X86_64
  1627. ---help---
  1628. The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
  1629. memory is used to determine the maximal offset in bytes that will
  1630. be applied to the kernel when kernel Address Space Layout
  1631. Randomization (kASLR) is active. This must be a multiple of
  1632. PHYSICAL_ALIGN.
  1633. On 32-bit this is limited to 512MiB by page table layouts. The
  1634. default is 512MiB.
  1635. On 64-bit this is limited by how the kernel fixmap page table is
  1636. positioned, so this cannot be larger than 1GiB currently. Without
  1637. RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
  1638. and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
  1639. modules area will shrink to compensate, up to the current maximum
  1640. 1GiB to 1GiB split. The default is 1GiB.
  1641. If unsure, leave at the default value.
  1642. # Relocation on x86 needs some additional build support
  1643. config X86_NEED_RELOCS
  1644. def_bool y
  1645. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1646. config PHYSICAL_ALIGN
  1647. hex "Alignment value to which kernel should be aligned"
  1648. default "0x200000"
  1649. range 0x2000 0x1000000 if X86_32
  1650. range 0x200000 0x1000000 if X86_64
  1651. ---help---
  1652. This value puts the alignment restrictions on physical address
  1653. where kernel is loaded and run from. Kernel is compiled for an
  1654. address which meets above alignment restriction.
  1655. If bootloader loads the kernel at a non-aligned address and
  1656. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1657. address aligned to above value and run from there.
  1658. If bootloader loads the kernel at a non-aligned address and
  1659. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1660. load address and decompress itself to the address it has been
  1661. compiled for and run from there. The address for which kernel is
  1662. compiled already meets above alignment restrictions. Hence the
  1663. end result is that kernel runs from a physical address meeting
  1664. above alignment restrictions.
  1665. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1666. this value must be a multiple of 0x200000.
  1667. Don't change this unless you know what you are doing.
  1668. config HOTPLUG_CPU
  1669. def_bool y
  1670. depends on SMP
  1671. config BOOTPARAM_HOTPLUG_CPU0
  1672. bool "Set default setting of cpu0_hotpluggable"
  1673. default n
  1674. depends on HOTPLUG_CPU
  1675. ---help---
  1676. Set whether default state of cpu0_hotpluggable is on or off.
  1677. Say Y here to enable CPU0 hotplug by default. If this switch
  1678. is turned on, there is no need to give cpu0_hotplug kernel
  1679. parameter and the CPU0 hotplug feature is enabled by default.
  1680. Please note: there are two known CPU0 dependencies if you want
  1681. to enable the CPU0 hotplug feature either by this switch or by
  1682. cpu0_hotplug kernel parameter.
  1683. First, resume from hibernate or suspend always starts from CPU0.
  1684. So hibernate and suspend are prevented if CPU0 is offline.
  1685. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1686. offline if any interrupt can not migrate out of CPU0. There may
  1687. be other CPU0 dependencies.
  1688. Please make sure the dependencies are under your control before
  1689. you enable this feature.
  1690. Say N if you don't want to enable CPU0 hotplug feature by default.
  1691. You still can enable the CPU0 hotplug feature at boot by kernel
  1692. parameter cpu0_hotplug.
  1693. config DEBUG_HOTPLUG_CPU0
  1694. def_bool n
  1695. prompt "Debug CPU0 hotplug"
  1696. depends on HOTPLUG_CPU
  1697. ---help---
  1698. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1699. soon as possible and boots up userspace with CPU0 offlined. User
  1700. can online CPU0 back after boot time.
  1701. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1702. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1703. compilation or giving cpu0_hotplug kernel parameter at boot.
  1704. If unsure, say N.
  1705. config COMPAT_VDSO
  1706. def_bool n
  1707. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1708. depends on X86_32 || IA32_EMULATION
  1709. ---help---
  1710. Certain buggy versions of glibc will crash if they are
  1711. presented with a 32-bit vDSO that is not mapped at the address
  1712. indicated in its segment table.
  1713. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1714. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1715. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1716. the only released version with the bug, but OpenSUSE 9
  1717. contains a buggy "glibc 2.3.2".
  1718. The symptom of the bug is that everything crashes on startup, saying:
  1719. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1720. Saying Y here changes the default value of the vdso32 boot
  1721. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1722. This works around the glibc bug but hurts performance.
  1723. If unsure, say N: if you are compiling your own kernel, you
  1724. are unlikely to be using a buggy version of glibc.
  1725. choice
  1726. prompt "vsyscall table for legacy applications"
  1727. depends on X86_64
  1728. default LEGACY_VSYSCALL_EMULATE
  1729. help
  1730. Legacy user code that does not know how to find the vDSO expects
  1731. to be able to issue three syscalls by calling fixed addresses in
  1732. kernel space. Since this location is not randomized with ASLR,
  1733. it can be used to assist security vulnerability exploitation.
  1734. This setting can be changed at boot time via the kernel command
  1735. line parameter vsyscall=[native|emulate|none].
  1736. On a system with recent enough glibc (2.14 or newer) and no
  1737. static binaries, you can say None without a performance penalty
  1738. to improve security.
  1739. If unsure, select "Emulate".
  1740. config LEGACY_VSYSCALL_NATIVE
  1741. bool "Native"
  1742. help
  1743. Actual executable code is located in the fixed vsyscall
  1744. address mapping, implementing time() efficiently. Since
  1745. this makes the mapping executable, it can be used during
  1746. security vulnerability exploitation (traditionally as
  1747. ROP gadgets). This configuration is not recommended.
  1748. config LEGACY_VSYSCALL_EMULATE
  1749. bool "Emulate"
  1750. help
  1751. The kernel traps and emulates calls into the fixed
  1752. vsyscall address mapping. This makes the mapping
  1753. non-executable, but it still contains known contents,
  1754. which could be used in certain rare security vulnerability
  1755. exploits. This configuration is recommended when userspace
  1756. still uses the vsyscall area.
  1757. config LEGACY_VSYSCALL_NONE
  1758. bool "None"
  1759. help
  1760. There will be no vsyscall mapping at all. This will
  1761. eliminate any risk of ASLR bypass due to the vsyscall
  1762. fixed address mapping. Attempts to use the vsyscalls
  1763. will be reported to dmesg, so that either old or
  1764. malicious userspace programs can be identified.
  1765. endchoice
  1766. config CMDLINE_BOOL
  1767. bool "Built-in kernel command line"
  1768. ---help---
  1769. Allow for specifying boot arguments to the kernel at
  1770. build time. On some systems (e.g. embedded ones), it is
  1771. necessary or convenient to provide some or all of the
  1772. kernel boot arguments with the kernel itself (that is,
  1773. to not rely on the boot loader to provide them.)
  1774. To compile command line arguments into the kernel,
  1775. set this option to 'Y', then fill in the
  1776. boot arguments in CONFIG_CMDLINE.
  1777. Systems with fully functional boot loaders (i.e. non-embedded)
  1778. should leave this option set to 'N'.
  1779. config CMDLINE
  1780. string "Built-in kernel command string"
  1781. depends on CMDLINE_BOOL
  1782. default ""
  1783. ---help---
  1784. Enter arguments here that should be compiled into the kernel
  1785. image and used at boot time. If the boot loader provides a
  1786. command line at boot time, it is appended to this string to
  1787. form the full kernel command line, when the system boots.
  1788. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1789. change this behavior.
  1790. In most cases, the command line (whether built-in or provided
  1791. by the boot loader) should specify the device for the root
  1792. file system.
  1793. config CMDLINE_OVERRIDE
  1794. bool "Built-in command line overrides boot loader arguments"
  1795. depends on CMDLINE_BOOL
  1796. ---help---
  1797. Set this option to 'Y' to have the kernel ignore the boot loader
  1798. command line, and use ONLY the built-in command line.
  1799. This is used to work around broken boot loaders. This should
  1800. be set to 'N' under normal conditions.
  1801. config MODIFY_LDT_SYSCALL
  1802. bool "Enable the LDT (local descriptor table)" if EXPERT
  1803. default y
  1804. ---help---
  1805. Linux can allow user programs to install a per-process x86
  1806. Local Descriptor Table (LDT) using the modify_ldt(2) system
  1807. call. This is required to run 16-bit or segmented code such as
  1808. DOSEMU or some Wine programs. It is also used by some very old
  1809. threading libraries.
  1810. Enabling this feature adds a small amount of overhead to
  1811. context switches and increases the low-level kernel attack
  1812. surface. Disabling it removes the modify_ldt(2) system call.
  1813. Saying 'N' here may make sense for embedded or server kernels.
  1814. source "kernel/livepatch/Kconfig"
  1815. endmenu
  1816. config ARCH_ENABLE_MEMORY_HOTPLUG
  1817. def_bool y
  1818. depends on X86_64 || (X86_32 && HIGHMEM)
  1819. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1820. def_bool y
  1821. depends on MEMORY_HOTPLUG
  1822. config USE_PERCPU_NUMA_NODE_ID
  1823. def_bool y
  1824. depends on NUMA
  1825. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  1826. def_bool y
  1827. depends on X86_64 || X86_PAE
  1828. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  1829. def_bool y
  1830. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  1831. menu "Power management and ACPI options"
  1832. config ARCH_HIBERNATION_HEADER
  1833. def_bool y
  1834. depends on X86_64 && HIBERNATION
  1835. source "kernel/power/Kconfig"
  1836. source "drivers/acpi/Kconfig"
  1837. source "drivers/sfi/Kconfig"
  1838. config X86_APM_BOOT
  1839. def_bool y
  1840. depends on APM
  1841. menuconfig APM
  1842. tristate "APM (Advanced Power Management) BIOS support"
  1843. depends on X86_32 && PM_SLEEP
  1844. ---help---
  1845. APM is a BIOS specification for saving power using several different
  1846. techniques. This is mostly useful for battery powered laptops with
  1847. APM compliant BIOSes. If you say Y here, the system time will be
  1848. reset after a RESUME operation, the /proc/apm device will provide
  1849. battery status information, and user-space programs will receive
  1850. notification of APM "events" (e.g. battery status change).
  1851. If you select "Y" here, you can disable actual use of the APM
  1852. BIOS by passing the "apm=off" option to the kernel at boot time.
  1853. Note that the APM support is almost completely disabled for
  1854. machines with more than one CPU.
  1855. In order to use APM, you will need supporting software. For location
  1856. and more information, read <file:Documentation/power/apm-acpi.txt>
  1857. and the Battery Powered Linux mini-HOWTO, available from
  1858. <http://www.tldp.org/docs.html#howto>.
  1859. This driver does not spin down disk drives (see the hdparm(8)
  1860. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1861. VESA-compliant "green" monitors.
  1862. This driver does not support the TI 4000M TravelMate and the ACER
  1863. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1864. desktop machines also don't have compliant BIOSes, and this driver
  1865. may cause those machines to panic during the boot phase.
  1866. Generally, if you don't have a battery in your machine, there isn't
  1867. much point in using this driver and you should say N. If you get
  1868. random kernel OOPSes or reboots that don't seem to be related to
  1869. anything, try disabling/enabling this option (or disabling/enabling
  1870. APM in your BIOS).
  1871. Some other things you should try when experiencing seemingly random,
  1872. "weird" problems:
  1873. 1) make sure that you have enough swap space and that it is
  1874. enabled.
  1875. 2) pass the "no-hlt" option to the kernel
  1876. 3) switch on floating point emulation in the kernel and pass
  1877. the "no387" option to the kernel
  1878. 4) pass the "floppy=nodma" option to the kernel
  1879. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1880. all but the first 4 MB of RAM)
  1881. 6) make sure that the CPU is not over clocked.
  1882. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1883. 8) disable the cache from your BIOS settings
  1884. 9) install a fan for the video card or exchange video RAM
  1885. 10) install a better fan for the CPU
  1886. 11) exchange RAM chips
  1887. 12) exchange the motherboard.
  1888. To compile this driver as a module, choose M here: the
  1889. module will be called apm.
  1890. if APM
  1891. config APM_IGNORE_USER_SUSPEND
  1892. bool "Ignore USER SUSPEND"
  1893. ---help---
  1894. This option will ignore USER SUSPEND requests. On machines with a
  1895. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1896. series notebooks, it is necessary to say Y because of a BIOS bug.
  1897. config APM_DO_ENABLE
  1898. bool "Enable PM at boot time"
  1899. ---help---
  1900. Enable APM features at boot time. From page 36 of the APM BIOS
  1901. specification: "When disabled, the APM BIOS does not automatically
  1902. power manage devices, enter the Standby State, enter the Suspend
  1903. State, or take power saving steps in response to CPU Idle calls."
  1904. This driver will make CPU Idle calls when Linux is idle (unless this
  1905. feature is turned off -- see "Do CPU IDLE calls", below). This
  1906. should always save battery power, but more complicated APM features
  1907. will be dependent on your BIOS implementation. You may need to turn
  1908. this option off if your computer hangs at boot time when using APM
  1909. support, or if it beeps continuously instead of suspending. Turn
  1910. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1911. T400CDT. This is off by default since most machines do fine without
  1912. this feature.
  1913. config APM_CPU_IDLE
  1914. depends on CPU_IDLE
  1915. bool "Make CPU Idle calls when idle"
  1916. ---help---
  1917. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1918. On some machines, this can activate improved power savings, such as
  1919. a slowed CPU clock rate, when the machine is idle. These idle calls
  1920. are made after the idle loop has run for some length of time (e.g.,
  1921. 333 mS). On some machines, this will cause a hang at boot time or
  1922. whenever the CPU becomes idle. (On machines with more than one CPU,
  1923. this option does nothing.)
  1924. config APM_DISPLAY_BLANK
  1925. bool "Enable console blanking using APM"
  1926. ---help---
  1927. Enable console blanking using the APM. Some laptops can use this to
  1928. turn off the LCD backlight when the screen blanker of the Linux
  1929. virtual console blanks the screen. Note that this is only used by
  1930. the virtual console screen blanker, and won't turn off the backlight
  1931. when using the X Window system. This also doesn't have anything to
  1932. do with your VESA-compliant power-saving monitor. Further, this
  1933. option doesn't work for all laptops -- it might not turn off your
  1934. backlight at all, or it might print a lot of errors to the console,
  1935. especially if you are using gpm.
  1936. config APM_ALLOW_INTS
  1937. bool "Allow interrupts during APM BIOS calls"
  1938. ---help---
  1939. Normally we disable external interrupts while we are making calls to
  1940. the APM BIOS as a measure to lessen the effects of a badly behaving
  1941. BIOS implementation. The BIOS should reenable interrupts if it
  1942. needs to. Unfortunately, some BIOSes do not -- especially those in
  1943. many of the newer IBM Thinkpads. If you experience hangs when you
  1944. suspend, try setting this to Y. Otherwise, say N.
  1945. endif # APM
  1946. source "drivers/cpufreq/Kconfig"
  1947. source "drivers/cpuidle/Kconfig"
  1948. source "drivers/idle/Kconfig"
  1949. endmenu
  1950. menu "Bus options (PCI etc.)"
  1951. config PCI
  1952. bool "PCI support"
  1953. default y
  1954. ---help---
  1955. Find out whether you have a PCI motherboard. PCI is the name of a
  1956. bus system, i.e. the way the CPU talks to the other stuff inside
  1957. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1958. VESA. If you have PCI, say Y, otherwise N.
  1959. choice
  1960. prompt "PCI access mode"
  1961. depends on X86_32 && PCI
  1962. default PCI_GOANY
  1963. ---help---
  1964. On PCI systems, the BIOS can be used to detect the PCI devices and
  1965. determine their configuration. However, some old PCI motherboards
  1966. have BIOS bugs and may crash if this is done. Also, some embedded
  1967. PCI-based systems don't have any BIOS at all. Linux can also try to
  1968. detect the PCI hardware directly without using the BIOS.
  1969. With this option, you can specify how Linux should detect the
  1970. PCI devices. If you choose "BIOS", the BIOS will be used,
  1971. if you choose "Direct", the BIOS won't be used, and if you
  1972. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1973. If you choose "Any", the kernel will try MMCONFIG, then the
  1974. direct access method and falls back to the BIOS if that doesn't
  1975. work. If unsure, go with the default, which is "Any".
  1976. config PCI_GOBIOS
  1977. bool "BIOS"
  1978. config PCI_GOMMCONFIG
  1979. bool "MMConfig"
  1980. config PCI_GODIRECT
  1981. bool "Direct"
  1982. config PCI_GOOLPC
  1983. bool "OLPC XO-1"
  1984. depends on OLPC
  1985. config PCI_GOANY
  1986. bool "Any"
  1987. endchoice
  1988. config PCI_BIOS
  1989. def_bool y
  1990. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1991. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1992. config PCI_DIRECT
  1993. def_bool y
  1994. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  1995. config PCI_MMCONFIG
  1996. def_bool y
  1997. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1998. config PCI_OLPC
  1999. def_bool y
  2000. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  2001. config PCI_XEN
  2002. def_bool y
  2003. depends on PCI && XEN
  2004. select SWIOTLB_XEN
  2005. config PCI_DOMAINS
  2006. def_bool y
  2007. depends on PCI
  2008. config PCI_MMCONFIG
  2009. bool "Support mmconfig PCI config space access"
  2010. depends on X86_64 && PCI && ACPI
  2011. config PCI_CNB20LE_QUIRK
  2012. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  2013. depends on PCI
  2014. help
  2015. Read the PCI windows out of the CNB20LE host bridge. This allows
  2016. PCI hotplug to work on systems with the CNB20LE chipset which do
  2017. not have ACPI.
  2018. There's no public spec for this chipset, and this functionality
  2019. is known to be incomplete.
  2020. You should say N unless you know you need this.
  2021. source "drivers/pci/pcie/Kconfig"
  2022. source "drivers/pci/Kconfig"
  2023. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2024. config ISA_DMA_API
  2025. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2026. default y
  2027. help
  2028. Enables ISA-style DMA support for devices requiring such controllers.
  2029. If unsure, say Y.
  2030. if X86_32
  2031. config ISA
  2032. bool "ISA support"
  2033. ---help---
  2034. Find out whether you have ISA slots on your motherboard. ISA is the
  2035. name of a bus system, i.e. the way the CPU talks to the other stuff
  2036. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2037. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2038. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2039. config EISA
  2040. bool "EISA support"
  2041. depends on ISA
  2042. ---help---
  2043. The Extended Industry Standard Architecture (EISA) bus was
  2044. developed as an open alternative to the IBM MicroChannel bus.
  2045. The EISA bus provided some of the features of the IBM MicroChannel
  2046. bus while maintaining backward compatibility with cards made for
  2047. the older ISA bus. The EISA bus saw limited use between 1988 and
  2048. 1995 when it was made obsolete by the PCI bus.
  2049. Say Y here if you are building a kernel for an EISA-based machine.
  2050. Otherwise, say N.
  2051. source "drivers/eisa/Kconfig"
  2052. config SCx200
  2053. tristate "NatSemi SCx200 support"
  2054. ---help---
  2055. This provides basic support for National Semiconductor's
  2056. (now AMD's) Geode processors. The driver probes for the
  2057. PCI-IDs of several on-chip devices, so its a good dependency
  2058. for other scx200_* drivers.
  2059. If compiled as a module, the driver is named scx200.
  2060. config SCx200HR_TIMER
  2061. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2062. depends on SCx200
  2063. default y
  2064. ---help---
  2065. This driver provides a clocksource built upon the on-chip
  2066. 27MHz high-resolution timer. Its also a workaround for
  2067. NSC Geode SC-1100's buggy TSC, which loses time when the
  2068. processor goes idle (as is done by the scheduler). The
  2069. other workaround is idle=poll boot option.
  2070. config OLPC
  2071. bool "One Laptop Per Child support"
  2072. depends on !X86_PAE
  2073. select GPIOLIB
  2074. select OF
  2075. select OF_PROMTREE
  2076. select IRQ_DOMAIN
  2077. ---help---
  2078. Add support for detecting the unique features of the OLPC
  2079. XO hardware.
  2080. config OLPC_XO1_PM
  2081. bool "OLPC XO-1 Power Management"
  2082. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2083. select MFD_CORE
  2084. ---help---
  2085. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2086. config OLPC_XO1_RTC
  2087. bool "OLPC XO-1 Real Time Clock"
  2088. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2089. ---help---
  2090. Add support for the XO-1 real time clock, which can be used as a
  2091. programmable wakeup source.
  2092. config OLPC_XO1_SCI
  2093. bool "OLPC XO-1 SCI extras"
  2094. depends on OLPC && OLPC_XO1_PM
  2095. depends on INPUT=y
  2096. select POWER_SUPPLY
  2097. select GPIO_CS5535
  2098. select MFD_CORE
  2099. ---help---
  2100. Add support for SCI-based features of the OLPC XO-1 laptop:
  2101. - EC-driven system wakeups
  2102. - Power button
  2103. - Ebook switch
  2104. - Lid switch
  2105. - AC adapter status updates
  2106. - Battery status updates
  2107. config OLPC_XO15_SCI
  2108. bool "OLPC XO-1.5 SCI extras"
  2109. depends on OLPC && ACPI
  2110. select POWER_SUPPLY
  2111. ---help---
  2112. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2113. - EC-driven system wakeups
  2114. - AC adapter status updates
  2115. - Battery status updates
  2116. config ALIX
  2117. bool "PCEngines ALIX System Support (LED setup)"
  2118. select GPIOLIB
  2119. ---help---
  2120. This option enables system support for the PCEngines ALIX.
  2121. At present this just sets up LEDs for GPIO control on
  2122. ALIX2/3/6 boards. However, other system specific setup should
  2123. get added here.
  2124. Note: You must still enable the drivers for GPIO and LED support
  2125. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2126. Note: You have to set alix.force=1 for boards with Award BIOS.
  2127. config NET5501
  2128. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2129. select GPIOLIB
  2130. ---help---
  2131. This option enables system support for the Soekris Engineering net5501.
  2132. config GEOS
  2133. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2134. select GPIOLIB
  2135. depends on DMI
  2136. ---help---
  2137. This option enables system support for the Traverse Technologies GEOS.
  2138. config TS5500
  2139. bool "Technologic Systems TS-5500 platform support"
  2140. depends on MELAN
  2141. select CHECK_SIGNATURE
  2142. select NEW_LEDS
  2143. select LEDS_CLASS
  2144. ---help---
  2145. This option enables system support for the Technologic Systems TS-5500.
  2146. endif # X86_32
  2147. config AMD_NB
  2148. def_bool y
  2149. depends on CPU_SUP_AMD && PCI
  2150. source "drivers/pcmcia/Kconfig"
  2151. source "drivers/pci/hotplug/Kconfig"
  2152. config RAPIDIO
  2153. tristate "RapidIO support"
  2154. depends on PCI
  2155. default n
  2156. help
  2157. If enabled this option will include drivers and the core
  2158. infrastructure code to support RapidIO interconnect devices.
  2159. source "drivers/rapidio/Kconfig"
  2160. config X86_SYSFB
  2161. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2162. help
  2163. Firmwares often provide initial graphics framebuffers so the BIOS,
  2164. bootloader or kernel can show basic video-output during boot for
  2165. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2166. Extensions and EFI-framebuffers for this, which are mostly limited
  2167. to x86.
  2168. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2169. framebuffers so the new generic system-framebuffer drivers can be
  2170. used on x86. If the framebuffer is not compatible with the generic
  2171. modes, it is adverticed as fallback platform framebuffer so legacy
  2172. drivers like efifb, vesafb and uvesafb can pick it up.
  2173. If this option is not selected, all system framebuffers are always
  2174. marked as fallback platform framebuffers as usual.
  2175. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2176. not be able to pick up generic system framebuffers if this option
  2177. is selected. You are highly encouraged to enable simplefb as
  2178. replacement if you select this option. simplefb can correctly deal
  2179. with generic system framebuffers. But you should still keep vesafb
  2180. and others enabled as fallback if a system framebuffer is
  2181. incompatible with simplefb.
  2182. If unsure, say Y.
  2183. endmenu
  2184. menu "Executable file formats / Emulations"
  2185. source "fs/Kconfig.binfmt"
  2186. config IA32_EMULATION
  2187. bool "IA32 Emulation"
  2188. depends on X86_64
  2189. select BINFMT_ELF
  2190. select COMPAT_BINFMT_ELF
  2191. select ARCH_WANT_OLD_COMPAT_IPC
  2192. ---help---
  2193. Include code to run legacy 32-bit programs under a
  2194. 64-bit kernel. You should likely turn this on, unless you're
  2195. 100% sure that you don't have any 32-bit programs left.
  2196. config IA32_AOUT
  2197. tristate "IA32 a.out support"
  2198. depends on IA32_EMULATION
  2199. ---help---
  2200. Support old a.out binaries in the 32bit emulation.
  2201. config X86_X32
  2202. bool "x32 ABI for 64-bit mode"
  2203. depends on X86_64
  2204. ---help---
  2205. Include code to run binaries for the x32 native 32-bit ABI
  2206. for 64-bit processors. An x32 process gets access to the
  2207. full 64-bit register file and wide data path while leaving
  2208. pointers at 32 bits for smaller memory footprint.
  2209. You will need a recent binutils (2.22 or later) with
  2210. elf32_x86_64 support enabled to compile a kernel with this
  2211. option set.
  2212. config COMPAT
  2213. def_bool y
  2214. depends on IA32_EMULATION || X86_X32
  2215. if COMPAT
  2216. config COMPAT_FOR_U64_ALIGNMENT
  2217. def_bool y
  2218. config SYSVIPC_COMPAT
  2219. def_bool y
  2220. depends on SYSVIPC
  2221. endif
  2222. endmenu
  2223. config HAVE_ATOMIC_IOMAP
  2224. def_bool y
  2225. depends on X86_32
  2226. config X86_DEV_DMA_OPS
  2227. bool
  2228. depends on X86_64 || STA2X11
  2229. config X86_DMA_REMAP
  2230. bool
  2231. depends on STA2X11
  2232. config PMC_ATOM
  2233. def_bool y
  2234. depends on PCI
  2235. source "net/Kconfig"
  2236. source "drivers/Kconfig"
  2237. source "drivers/firmware/Kconfig"
  2238. source "fs/Kconfig"
  2239. source "arch/x86/Kconfig.debug"
  2240. source "security/Kconfig"
  2241. source "crypto/Kconfig"
  2242. source "arch/x86/kvm/Kconfig"
  2243. source "lib/Kconfig"