Kconfig 90 KB

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