Kconfig 94 KB

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  1. # SPDX-License-Identifier: GPL-2.0
  2. # Select 32 or 64 bit
  3. config 64BIT
  4. bool "64-bit kernel" if ARCH = "x86"
  5. default ARCH != "i386"
  6. ---help---
  7. Say yes to build a 64-bit kernel - formerly known as x86_64
  8. Say no to build a 32-bit kernel - formerly known as i386
  9. config X86_32
  10. def_bool y
  11. depends on !64BIT
  12. # Options that are inherently 32-bit kernel only:
  13. select ARCH_WANT_IPC_PARSE_VERSION
  14. select CLKSRC_I8253
  15. select CLONE_BACKWARDS
  16. select HAVE_AOUT
  17. select HAVE_GENERIC_DMA_COHERENT
  18. select MODULES_USE_ELF_REL
  19. select OLD_SIGACTION
  20. config X86_64
  21. def_bool y
  22. depends on 64BIT
  23. # Options that are inherently 64-bit kernel only:
  24. select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
  25. select ARCH_SUPPORTS_INT128
  26. select ARCH_USE_CMPXCHG_LOCKREF
  27. select HAVE_ARCH_SOFT_DIRTY
  28. select MODULES_USE_ELF_RELA
  29. select NEED_DMA_MAP_STATE
  30. select SWIOTLB
  31. select X86_DEV_DMA_OPS
  32. select ARCH_HAS_SYSCALL_WRAPPER
  33. #
  34. # Arch settings
  35. #
  36. # ( Note that options that are marked 'if X86_64' could in principle be
  37. # ported to 32-bit as well. )
  38. #
  39. config X86
  40. def_bool y
  41. #
  42. # Note: keep this list sorted alphabetically
  43. #
  44. select ACPI_LEGACY_TABLES_LOOKUP if ACPI
  45. select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
  46. select ANON_INODES
  47. select ARCH_CLOCKSOURCE_DATA
  48. select ARCH_DISCARD_MEMBLOCK
  49. select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
  50. select ARCH_HAS_DEBUG_VIRTUAL
  51. select ARCH_HAS_DEVMEM_IS_ALLOWED
  52. select ARCH_HAS_ELF_RANDOMIZE
  53. select ARCH_HAS_FAST_MULTIPLIER
  54. select ARCH_HAS_FILTER_PGPROT
  55. select ARCH_HAS_FORTIFY_SOURCE
  56. select ARCH_HAS_GCOV_PROFILE_ALL
  57. select ARCH_HAS_KCOV if X86_64
  58. select ARCH_HAS_MEMBARRIER_SYNC_CORE
  59. select ARCH_HAS_PMEM_API if X86_64
  60. select ARCH_HAS_REFCOUNT
  61. select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
  62. select ARCH_HAS_SET_MEMORY
  63. select ARCH_HAS_SG_CHAIN
  64. select ARCH_HAS_STRICT_KERNEL_RWX
  65. select ARCH_HAS_STRICT_MODULE_RWX
  66. select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
  67. select ARCH_HAS_UBSAN_SANITIZE_ALL
  68. select ARCH_HAS_ZONE_DEVICE if X86_64
  69. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  70. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  71. select ARCH_MIGHT_HAVE_PC_PARPORT
  72. select ARCH_MIGHT_HAVE_PC_SERIO
  73. select ARCH_SUPPORTS_ATOMIC_RMW
  74. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  75. select ARCH_USE_BUILTIN_BSWAP
  76. select ARCH_USE_QUEUED_RWLOCKS
  77. select ARCH_USE_QUEUED_SPINLOCKS
  78. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
  79. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  80. select ARCH_WANTS_THP_SWAP if X86_64
  81. select BUILDTIME_EXTABLE_SORT
  82. select CLKEVT_I8253
  83. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  84. select CLOCKSOURCE_WATCHDOG
  85. select DCACHE_WORD_ACCESS
  86. select DMA_DIRECT_OPS
  87. select EDAC_ATOMIC_SCRUB
  88. select EDAC_SUPPORT
  89. select GENERIC_CLOCKEVENTS
  90. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  91. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  92. select GENERIC_CMOS_UPDATE
  93. select GENERIC_CPU_AUTOPROBE
  94. select GENERIC_CPU_VULNERABILITIES
  95. select GENERIC_EARLY_IOREMAP
  96. select GENERIC_FIND_FIRST_BIT
  97. select GENERIC_IOMAP
  98. select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
  99. select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
  100. select GENERIC_IRQ_MIGRATION if SMP
  101. select GENERIC_IRQ_PROBE
  102. select GENERIC_IRQ_RESERVATION_MODE
  103. select GENERIC_IRQ_SHOW
  104. select GENERIC_PENDING_IRQ if SMP
  105. select GENERIC_SMP_IDLE_THREAD
  106. select GENERIC_STRNCPY_FROM_USER
  107. select GENERIC_STRNLEN_USER
  108. select GENERIC_TIME_VSYSCALL
  109. select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
  110. select HAVE_ACPI_APEI if ACPI
  111. select HAVE_ACPI_APEI_NMI if ACPI
  112. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  113. select HAVE_ARCH_AUDITSYSCALL
  114. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  115. select HAVE_ARCH_JUMP_LABEL
  116. select HAVE_ARCH_KASAN if X86_64
  117. select HAVE_ARCH_KGDB
  118. select HAVE_ARCH_MMAP_RND_BITS if MMU
  119. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
  120. select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
  121. select HAVE_ARCH_SECCOMP_FILTER
  122. select HAVE_ARCH_THREAD_STRUCT_WHITELIST
  123. select HAVE_ARCH_TRACEHOOK
  124. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  125. select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
  126. select HAVE_ARCH_VMAP_STACK if X86_64
  127. select HAVE_ARCH_WITHIN_STACK_FRAMES
  128. select HAVE_CC_STACKPROTECTOR
  129. select HAVE_CMPXCHG_DOUBLE
  130. select HAVE_CMPXCHG_LOCAL
  131. select HAVE_CONTEXT_TRACKING if X86_64
  132. select HAVE_COPY_THREAD_TLS
  133. select HAVE_C_RECORDMCOUNT
  134. select HAVE_DEBUG_KMEMLEAK
  135. select HAVE_DEBUG_STACKOVERFLOW
  136. select HAVE_DMA_CONTIGUOUS
  137. select HAVE_DYNAMIC_FTRACE
  138. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  139. select HAVE_EBPF_JIT if X86_64
  140. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  141. select HAVE_EXIT_THREAD
  142. select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
  143. select HAVE_FTRACE_MCOUNT_RECORD
  144. select HAVE_FUNCTION_GRAPH_TRACER
  145. select HAVE_FUNCTION_TRACER
  146. select HAVE_GCC_PLUGINS
  147. select HAVE_HW_BREAKPOINT
  148. select HAVE_IDE
  149. select HAVE_IOREMAP_PROT
  150. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  151. select HAVE_IRQ_TIME_ACCOUNTING
  152. select HAVE_KERNEL_BZIP2
  153. select HAVE_KERNEL_GZIP
  154. select HAVE_KERNEL_LZ4
  155. select HAVE_KERNEL_LZMA
  156. select HAVE_KERNEL_LZO
  157. select HAVE_KERNEL_XZ
  158. select HAVE_KPROBES
  159. select HAVE_KPROBES_ON_FTRACE
  160. select HAVE_FUNCTION_ERROR_INJECTION
  161. select HAVE_KRETPROBES
  162. select HAVE_KVM
  163. select HAVE_LIVEPATCH if X86_64
  164. select HAVE_MEMBLOCK
  165. select HAVE_MEMBLOCK_NODE_MAP
  166. select HAVE_MIXED_BREAKPOINTS_REGS
  167. select HAVE_MOD_ARCH_SPECIFIC
  168. select HAVE_NMI
  169. select HAVE_OPROFILE
  170. select HAVE_OPTPROBES
  171. select HAVE_PCSPKR_PLATFORM
  172. select HAVE_PERF_EVENTS
  173. select HAVE_PERF_EVENTS_NMI
  174. select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
  175. select HAVE_PERF_REGS
  176. select HAVE_PERF_USER_STACK_DUMP
  177. select HAVE_RCU_TABLE_FREE
  178. select HAVE_REGS_AND_STACK_ACCESS_API
  179. select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
  180. select HAVE_STACK_VALIDATION if X86_64
  181. select HAVE_SYSCALL_TRACEPOINTS
  182. select HAVE_UNSTABLE_SCHED_CLOCK
  183. select HAVE_USER_RETURN_NOTIFIER
  184. select IRQ_FORCED_THREADING
  185. select NEED_SG_DMA_LENGTH
  186. select PCI_LOCKLESS_CONFIG
  187. select PERF_EVENTS
  188. select RTC_LIB
  189. select RTC_MC146818_LIB
  190. select SPARSE_IRQ
  191. select SRCU
  192. select SYSCTL_EXCEPTION_TRACE
  193. select THREAD_INFO_IN_TASK
  194. select USER_STACKTRACE_SUPPORT
  195. select VIRT_TO_BUS
  196. select X86_FEATURE_NAMES if PROC_FS
  197. config INSTRUCTION_DECODER
  198. def_bool y
  199. depends on KPROBES || PERF_EVENTS || UPROBES
  200. config OUTPUT_FORMAT
  201. string
  202. default "elf32-i386" if X86_32
  203. default "elf64-x86-64" if X86_64
  204. config ARCH_DEFCONFIG
  205. string
  206. default "arch/x86/configs/i386_defconfig" if X86_32
  207. default "arch/x86/configs/x86_64_defconfig" if X86_64
  208. config LOCKDEP_SUPPORT
  209. def_bool y
  210. config STACKTRACE_SUPPORT
  211. def_bool y
  212. config MMU
  213. def_bool y
  214. config ARCH_MMAP_RND_BITS_MIN
  215. default 28 if 64BIT
  216. default 8
  217. config ARCH_MMAP_RND_BITS_MAX
  218. default 32 if 64BIT
  219. default 16
  220. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  221. default 8
  222. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  223. default 16
  224. config SBUS
  225. bool
  226. config GENERIC_ISA_DMA
  227. def_bool y
  228. depends on ISA_DMA_API
  229. config GENERIC_BUG
  230. def_bool y
  231. depends on BUG
  232. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  233. config GENERIC_BUG_RELATIVE_POINTERS
  234. bool
  235. config GENERIC_HWEIGHT
  236. def_bool y
  237. config ARCH_MAY_HAVE_PC_FDC
  238. def_bool y
  239. depends on ISA_DMA_API
  240. config RWSEM_XCHGADD_ALGORITHM
  241. def_bool y
  242. config GENERIC_CALIBRATE_DELAY
  243. def_bool y
  244. config ARCH_HAS_CPU_RELAX
  245. def_bool y
  246. config ARCH_HAS_CACHE_LINE_SIZE
  247. def_bool y
  248. config ARCH_HAS_FILTER_PGPROT
  249. def_bool y
  250. config HAVE_SETUP_PER_CPU_AREA
  251. def_bool y
  252. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  253. def_bool y
  254. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  255. def_bool y
  256. config ARCH_HIBERNATION_POSSIBLE
  257. def_bool y
  258. config ARCH_SUSPEND_POSSIBLE
  259. def_bool y
  260. config ARCH_WANT_HUGE_PMD_SHARE
  261. def_bool y
  262. config ARCH_WANT_GENERAL_HUGETLB
  263. def_bool y
  264. config ZONE_DMA32
  265. def_bool y if X86_64
  266. config AUDIT_ARCH
  267. def_bool y if X86_64
  268. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  269. def_bool y
  270. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  271. def_bool y
  272. config KASAN_SHADOW_OFFSET
  273. hex
  274. depends on KASAN
  275. default 0xdffffc0000000000
  276. config HAVE_INTEL_TXT
  277. def_bool y
  278. depends on INTEL_IOMMU && ACPI
  279. config X86_32_SMP
  280. def_bool y
  281. depends on X86_32 && SMP
  282. config X86_64_SMP
  283. def_bool y
  284. depends on X86_64 && SMP
  285. config X86_32_LAZY_GS
  286. def_bool y
  287. depends on X86_32 && CC_STACKPROTECTOR_NONE
  288. config ARCH_SUPPORTS_UPROBES
  289. def_bool y
  290. config FIX_EARLYCON_MEM
  291. def_bool y
  292. config PGTABLE_LEVELS
  293. int
  294. default 5 if X86_5LEVEL
  295. default 4 if X86_64
  296. default 3 if X86_PAE
  297. default 2
  298. source "init/Kconfig"
  299. source "kernel/Kconfig.freezer"
  300. menu "Processor type and features"
  301. config ZONE_DMA
  302. bool "DMA memory allocation support" if EXPERT
  303. default y
  304. help
  305. DMA memory allocation support allows devices with less than 32-bit
  306. addressing to allocate within the first 16MB of address space.
  307. Disable if no such devices will be used.
  308. If unsure, say Y.
  309. config SMP
  310. bool "Symmetric multi-processing support"
  311. ---help---
  312. This enables support for systems with more than one CPU. If you have
  313. a system with only one CPU, say N. If you have a system with more
  314. than one CPU, say Y.
  315. If you say N here, the kernel will run on uni- and multiprocessor
  316. machines, but will use only one CPU of a multiprocessor machine. If
  317. you say Y here, the kernel will run on many, but not all,
  318. uniprocessor machines. On a uniprocessor machine, the kernel
  319. will run faster if you say N here.
  320. Note that if you say Y here and choose architecture "586" or
  321. "Pentium" under "Processor family", the kernel will not work on 486
  322. architectures. Similarly, multiprocessor kernels for the "PPro"
  323. architecture may not work on all Pentium based boards.
  324. People using multiprocessor machines who say Y here should also say
  325. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  326. Management" code will be disabled if you say Y here.
  327. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  328. <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
  329. <http://www.tldp.org/docs.html#howto>.
  330. If you don't know what to do here, say N.
  331. config X86_FEATURE_NAMES
  332. bool "Processor feature human-readable names" if EMBEDDED
  333. default y
  334. ---help---
  335. This option compiles in a table of x86 feature bits and corresponding
  336. names. This is required to support /proc/cpuinfo and a few kernel
  337. messages. You can disable this to save space, at the expense of
  338. making those few kernel messages show numeric feature bits instead.
  339. If in doubt, say Y.
  340. config X86_X2APIC
  341. bool "Support x2apic"
  342. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  343. ---help---
  344. This enables x2apic support on CPUs that have this feature.
  345. This allows 32-bit apic IDs (so it can support very large systems),
  346. and accesses the local apic via MSRs not via mmio.
  347. If you don't know what to do here, say N.
  348. config X86_MPPARSE
  349. bool "Enable MPS table" if ACPI || SFI
  350. default y
  351. depends on X86_LOCAL_APIC
  352. ---help---
  353. For old smp systems that do not have proper acpi support. Newer systems
  354. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  355. config GOLDFISH
  356. def_bool y
  357. depends on X86_GOLDFISH
  358. config RETPOLINE
  359. bool "Avoid speculative indirect branches in kernel"
  360. default y
  361. select STACK_VALIDATION if HAVE_STACK_VALIDATION
  362. help
  363. Compile kernel with the retpoline compiler options to guard against
  364. kernel-to-user data leaks by avoiding speculative indirect
  365. branches. Requires a compiler with -mindirect-branch=thunk-extern
  366. support for full protection. The kernel may run slower.
  367. Without compiler support, at least indirect branches in assembler
  368. code are eliminated. Since this includes the syscall entry path,
  369. it is not entirely pointless.
  370. config INTEL_RDT
  371. bool "Intel Resource Director Technology support"
  372. default n
  373. depends on X86 && CPU_SUP_INTEL
  374. select KERNFS
  375. help
  376. Select to enable resource allocation and monitoring which are
  377. sub-features of Intel Resource Director Technology(RDT). More
  378. information about RDT can be found in the Intel x86
  379. Architecture Software Developer Manual.
  380. Say N if unsure.
  381. if X86_32
  382. config X86_BIGSMP
  383. bool "Support for big SMP systems with more than 8 CPUs"
  384. depends on SMP
  385. ---help---
  386. This option is needed for the systems that have more than 8 CPUs
  387. config X86_EXTENDED_PLATFORM
  388. bool "Support for extended (non-PC) x86 platforms"
  389. default y
  390. ---help---
  391. If you disable this option then the kernel will only support
  392. standard PC platforms. (which covers the vast majority of
  393. systems out there.)
  394. If you enable this option then you'll be able to select support
  395. for the following (non-PC) 32 bit x86 platforms:
  396. Goldfish (Android emulator)
  397. AMD Elan
  398. RDC R-321x SoC
  399. SGI 320/540 (Visual Workstation)
  400. STA2X11-based (e.g. Northville)
  401. Moorestown MID devices
  402. If you have one of these systems, or if you want to build a
  403. generic distribution kernel, say Y here - otherwise say N.
  404. endif
  405. if X86_64
  406. config X86_EXTENDED_PLATFORM
  407. bool "Support for extended (non-PC) x86 platforms"
  408. default y
  409. ---help---
  410. If you disable this option then the kernel will only support
  411. standard PC platforms. (which covers the vast majority of
  412. systems out there.)
  413. If you enable this option then you'll be able to select support
  414. for the following (non-PC) 64 bit x86 platforms:
  415. Numascale NumaChip
  416. ScaleMP vSMP
  417. SGI Ultraviolet
  418. If you have one of these systems, or if you want to build a
  419. generic distribution kernel, say Y here - otherwise say N.
  420. endif
  421. # This is an alphabetically sorted list of 64 bit extended platforms
  422. # Please maintain the alphabetic order if and when there are additions
  423. config X86_NUMACHIP
  424. bool "Numascale NumaChip"
  425. depends on X86_64
  426. depends on X86_EXTENDED_PLATFORM
  427. depends on NUMA
  428. depends on SMP
  429. depends on X86_X2APIC
  430. depends on PCI_MMCONFIG
  431. ---help---
  432. Adds support for Numascale NumaChip large-SMP systems. Needed to
  433. enable more than ~168 cores.
  434. If you don't have one of these, you should say N here.
  435. config X86_VSMP
  436. bool "ScaleMP vSMP"
  437. select HYPERVISOR_GUEST
  438. select PARAVIRT
  439. depends on X86_64 && PCI
  440. depends on X86_EXTENDED_PLATFORM
  441. depends on SMP
  442. ---help---
  443. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  444. supposed to run on these EM64T-based machines. Only choose this option
  445. if you have one of these machines.
  446. config X86_UV
  447. bool "SGI Ultraviolet"
  448. depends on X86_64
  449. depends on X86_EXTENDED_PLATFORM
  450. depends on NUMA
  451. depends on EFI
  452. depends on X86_X2APIC
  453. depends on PCI
  454. ---help---
  455. This option is needed in order to support SGI Ultraviolet systems.
  456. If you don't have one of these, you should say N here.
  457. # Following is an alphabetically sorted list of 32 bit extended platforms
  458. # Please maintain the alphabetic order if and when there are additions
  459. config X86_GOLDFISH
  460. bool "Goldfish (Virtual Platform)"
  461. depends on X86_EXTENDED_PLATFORM
  462. ---help---
  463. Enable support for the Goldfish virtual platform used primarily
  464. for Android development. Unless you are building for the Android
  465. Goldfish emulator say N here.
  466. config X86_INTEL_CE
  467. bool "CE4100 TV platform"
  468. depends on PCI
  469. depends on PCI_GODIRECT
  470. depends on X86_IO_APIC
  471. depends on X86_32
  472. depends on X86_EXTENDED_PLATFORM
  473. select X86_REBOOTFIXUPS
  474. select OF
  475. select OF_EARLY_FLATTREE
  476. ---help---
  477. Select for the Intel CE media processor (CE4100) SOC.
  478. This option compiles in support for the CE4100 SOC for settop
  479. boxes and media devices.
  480. config X86_INTEL_MID
  481. bool "Intel MID platform support"
  482. depends on X86_EXTENDED_PLATFORM
  483. depends on X86_PLATFORM_DEVICES
  484. depends on PCI
  485. depends on X86_64 || (PCI_GOANY && X86_32)
  486. depends on X86_IO_APIC
  487. select SFI
  488. select I2C
  489. select DW_APB_TIMER
  490. select APB_TIMER
  491. select INTEL_SCU_IPC
  492. select MFD_INTEL_MSIC
  493. ---help---
  494. Select to build a kernel capable of supporting Intel MID (Mobile
  495. Internet Device) platform systems which do not have the PCI legacy
  496. interfaces. If you are building for a PC class system say N here.
  497. Intel MID platforms are based on an Intel processor and chipset which
  498. consume less power than most of the x86 derivatives.
  499. config X86_INTEL_QUARK
  500. bool "Intel Quark platform support"
  501. depends on X86_32
  502. depends on X86_EXTENDED_PLATFORM
  503. depends on X86_PLATFORM_DEVICES
  504. depends on X86_TSC
  505. depends on PCI
  506. depends on PCI_GOANY
  507. depends on X86_IO_APIC
  508. select IOSF_MBI
  509. select INTEL_IMR
  510. select COMMON_CLK
  511. ---help---
  512. Select to include support for Quark X1000 SoC.
  513. Say Y here if you have a Quark based system such as the Arduino
  514. compatible Intel Galileo.
  515. config X86_INTEL_LPSS
  516. bool "Intel Low Power Subsystem Support"
  517. depends on X86 && ACPI
  518. select COMMON_CLK
  519. select PINCTRL
  520. select IOSF_MBI
  521. ---help---
  522. Select to build support for Intel Low Power Subsystem such as
  523. found on Intel Lynxpoint PCH. Selecting this option enables
  524. things like clock tree (common clock framework) and pincontrol
  525. which are needed by the LPSS peripheral drivers.
  526. config X86_AMD_PLATFORM_DEVICE
  527. bool "AMD ACPI2Platform devices support"
  528. depends on ACPI
  529. select COMMON_CLK
  530. select PINCTRL
  531. ---help---
  532. Select to interpret AMD specific ACPI device to platform device
  533. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  534. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  535. implemented under PINCTRL subsystem.
  536. config IOSF_MBI
  537. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  538. depends on PCI
  539. ---help---
  540. This option enables sideband register access support for Intel SoC
  541. platforms. On these platforms the IOSF sideband is used in lieu of
  542. MSR's for some register accesses, mostly but not limited to thermal
  543. and power. Drivers may query the availability of this device to
  544. determine if they need the sideband in order to work on these
  545. platforms. The sideband is available on the following SoC products.
  546. This list is not meant to be exclusive.
  547. - BayTrail
  548. - Braswell
  549. - Quark
  550. You should say Y if you are running a kernel on one of these SoC's.
  551. config IOSF_MBI_DEBUG
  552. bool "Enable IOSF sideband access through debugfs"
  553. depends on IOSF_MBI && DEBUG_FS
  554. ---help---
  555. Select this option to expose the IOSF sideband access registers (MCR,
  556. MDR, MCRX) through debugfs to write and read register information from
  557. different units on the SoC. This is most useful for obtaining device
  558. state information for debug and analysis. As this is a general access
  559. mechanism, users of this option would have specific knowledge of the
  560. device they want to access.
  561. If you don't require the option or are in doubt, say N.
  562. config X86_RDC321X
  563. bool "RDC R-321x SoC"
  564. depends on X86_32
  565. depends on X86_EXTENDED_PLATFORM
  566. select M486
  567. select X86_REBOOTFIXUPS
  568. ---help---
  569. This option is needed for RDC R-321x system-on-chip, also known
  570. as R-8610-(G).
  571. If you don't have one of these chips, you should say N here.
  572. config X86_32_NON_STANDARD
  573. bool "Support non-standard 32-bit SMP architectures"
  574. depends on X86_32 && SMP
  575. depends on X86_EXTENDED_PLATFORM
  576. ---help---
  577. This option compiles in the bigsmp and STA2X11 default
  578. subarchitectures. It is intended for a generic binary
  579. kernel. If you select them all, kernel will probe it one by
  580. one and will fallback to default.
  581. # Alphabetically sorted list of Non standard 32 bit platforms
  582. config X86_SUPPORTS_MEMORY_FAILURE
  583. def_bool y
  584. # MCE code calls memory_failure():
  585. depends on X86_MCE
  586. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  587. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  588. depends on X86_64 || !SPARSEMEM
  589. select ARCH_SUPPORTS_MEMORY_FAILURE
  590. config STA2X11
  591. bool "STA2X11 Companion Chip Support"
  592. depends on X86_32_NON_STANDARD && PCI
  593. select ARCH_HAS_PHYS_TO_DMA
  594. select X86_DEV_DMA_OPS
  595. select X86_DMA_REMAP
  596. select SWIOTLB
  597. select MFD_STA2X11
  598. select GPIOLIB
  599. default n
  600. ---help---
  601. This adds support for boards based on the STA2X11 IO-Hub,
  602. a.k.a. "ConneXt". The chip is used in place of the standard
  603. PC chipset, so all "standard" peripherals are missing. If this
  604. option is selected the kernel will still be able to boot on
  605. standard PC machines.
  606. config X86_32_IRIS
  607. tristate "Eurobraille/Iris poweroff module"
  608. depends on X86_32
  609. ---help---
  610. The Iris machines from EuroBraille do not have APM or ACPI support
  611. to shut themselves down properly. A special I/O sequence is
  612. needed to do so, which is what this module does at
  613. kernel shutdown.
  614. This is only for Iris machines from EuroBraille.
  615. If unused, say N.
  616. config SCHED_OMIT_FRAME_POINTER
  617. def_bool y
  618. prompt "Single-depth WCHAN output"
  619. depends on X86
  620. ---help---
  621. Calculate simpler /proc/<PID>/wchan values. If this option
  622. is disabled then wchan values will recurse back to the
  623. caller function. This provides more accurate wchan values,
  624. at the expense of slightly more scheduling overhead.
  625. If in doubt, say "Y".
  626. menuconfig HYPERVISOR_GUEST
  627. bool "Linux guest support"
  628. ---help---
  629. Say Y here to enable options for running Linux under various hyper-
  630. visors. This option enables basic hypervisor detection and platform
  631. setup.
  632. If you say N, all options in this submenu will be skipped and
  633. disabled, and Linux guest support won't be built in.
  634. if HYPERVISOR_GUEST
  635. config PARAVIRT
  636. bool "Enable paravirtualization code"
  637. ---help---
  638. This changes the kernel so it can modify itself when it is run
  639. under a hypervisor, potentially improving performance significantly
  640. over full virtualization. However, when run without a hypervisor
  641. the kernel is theoretically slower and slightly larger.
  642. config PARAVIRT_DEBUG
  643. bool "paravirt-ops debugging"
  644. depends on PARAVIRT && DEBUG_KERNEL
  645. ---help---
  646. Enable to debug paravirt_ops internals. Specifically, BUG if
  647. a paravirt_op is missing when it is called.
  648. config PARAVIRT_SPINLOCKS
  649. bool "Paravirtualization layer for spinlocks"
  650. depends on PARAVIRT && SMP
  651. ---help---
  652. Paravirtualized spinlocks allow a pvops backend to replace the
  653. spinlock implementation with something virtualization-friendly
  654. (for example, block the virtual CPU rather than spinning).
  655. It has a minimal impact on native kernels and gives a nice performance
  656. benefit on paravirtualized KVM / Xen kernels.
  657. If you are unsure how to answer this question, answer Y.
  658. config QUEUED_LOCK_STAT
  659. bool "Paravirt queued spinlock statistics"
  660. depends on PARAVIRT_SPINLOCKS && DEBUG_FS
  661. ---help---
  662. Enable the collection of statistical data on the slowpath
  663. behavior of paravirtualized queued spinlocks and report
  664. them on debugfs.
  665. source "arch/x86/xen/Kconfig"
  666. config KVM_GUEST
  667. bool "KVM Guest support (including kvmclock)"
  668. depends on PARAVIRT
  669. select PARAVIRT_CLOCK
  670. default y
  671. ---help---
  672. This option enables various optimizations for running under the KVM
  673. hypervisor. It includes a paravirtualized clock, so that instead
  674. of relying on a PIT (or probably other) emulation by the
  675. underlying device model, the host provides the guest with
  676. timing infrastructure such as time of day, and system time
  677. config KVM_DEBUG_FS
  678. bool "Enable debug information for KVM Guests in debugfs"
  679. depends on KVM_GUEST && DEBUG_FS
  680. default n
  681. ---help---
  682. This option enables collection of various statistics for KVM guest.
  683. Statistics are displayed in debugfs filesystem. Enabling this option
  684. may incur significant overhead.
  685. config PARAVIRT_TIME_ACCOUNTING
  686. bool "Paravirtual steal time accounting"
  687. depends on PARAVIRT
  688. default n
  689. ---help---
  690. Select this option to enable fine granularity task steal time
  691. accounting. Time spent executing other tasks in parallel with
  692. the current vCPU is discounted from the vCPU power. To account for
  693. that, there can be a small performance impact.
  694. If in doubt, say N here.
  695. config PARAVIRT_CLOCK
  696. bool
  697. config JAILHOUSE_GUEST
  698. bool "Jailhouse non-root cell support"
  699. depends on X86_64 && PCI
  700. select X86_PM_TIMER
  701. ---help---
  702. This option allows to run Linux as guest in a Jailhouse non-root
  703. cell. You can leave this option disabled if you only want to start
  704. Jailhouse and run Linux afterwards in the root cell.
  705. endif #HYPERVISOR_GUEST
  706. config NO_BOOTMEM
  707. def_bool y
  708. source "arch/x86/Kconfig.cpu"
  709. config HPET_TIMER
  710. def_bool X86_64
  711. prompt "HPET Timer Support" if X86_32
  712. ---help---
  713. Use the IA-PC HPET (High Precision Event Timer) to manage
  714. time in preference to the PIT and RTC, if a HPET is
  715. present.
  716. HPET is the next generation timer replacing legacy 8254s.
  717. The HPET provides a stable time base on SMP
  718. systems, unlike the TSC, but it is more expensive to access,
  719. as it is off-chip. The interface used is documented
  720. in the HPET spec, revision 1.
  721. You can safely choose Y here. However, HPET will only be
  722. activated if the platform and the BIOS support this feature.
  723. Otherwise the 8254 will be used for timing services.
  724. Choose N to continue using the legacy 8254 timer.
  725. config HPET_EMULATE_RTC
  726. def_bool y
  727. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  728. config APB_TIMER
  729. def_bool y if X86_INTEL_MID
  730. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  731. select DW_APB_TIMER
  732. depends on X86_INTEL_MID && SFI
  733. help
  734. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  735. The APBT provides a stable time base on SMP
  736. systems, unlike the TSC, but it is more expensive to access,
  737. as it is off-chip. APB timers are always running regardless of CPU
  738. C states, they are used as per CPU clockevent device when possible.
  739. # Mark as expert because too many people got it wrong.
  740. # The code disables itself when not needed.
  741. config DMI
  742. default y
  743. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  744. bool "Enable DMI scanning" if EXPERT
  745. ---help---
  746. Enabled scanning of DMI to identify machine quirks. Say Y
  747. here unless you have verified that your setup is not
  748. affected by entries in the DMI blacklist. Required by PNP
  749. BIOS code.
  750. config GART_IOMMU
  751. bool "Old AMD GART IOMMU support"
  752. select IOMMU_HELPER
  753. select SWIOTLB
  754. depends on X86_64 && PCI && AMD_NB
  755. ---help---
  756. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  757. GART based hardware IOMMUs.
  758. The GART supports full DMA access for devices with 32-bit access
  759. limitations, on systems with more than 3 GB. This is usually needed
  760. for USB, sound, many IDE/SATA chipsets and some other devices.
  761. Newer systems typically have a modern AMD IOMMU, supported via
  762. the CONFIG_AMD_IOMMU=y config option.
  763. In normal configurations this driver is only active when needed:
  764. there's more than 3 GB of memory and the system contains a
  765. 32-bit limited device.
  766. If unsure, say Y.
  767. config CALGARY_IOMMU
  768. bool "IBM Calgary IOMMU support"
  769. select IOMMU_HELPER
  770. select SWIOTLB
  771. depends on X86_64 && PCI
  772. ---help---
  773. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  774. systems. Needed to run systems with more than 3GB of memory
  775. properly with 32-bit PCI devices that do not support DAC
  776. (Double Address Cycle). Calgary also supports bus level
  777. isolation, where all DMAs pass through the IOMMU. This
  778. prevents them from going anywhere except their intended
  779. destination. This catches hard-to-find kernel bugs and
  780. mis-behaving drivers and devices that do not use the DMA-API
  781. properly to set up their DMA buffers. The IOMMU can be
  782. turned off at boot time with the iommu=off parameter.
  783. Normally the kernel will make the right choice by itself.
  784. If unsure, say Y.
  785. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  786. def_bool y
  787. prompt "Should Calgary be enabled by default?"
  788. depends on CALGARY_IOMMU
  789. ---help---
  790. Should Calgary be enabled by default? if you choose 'y', Calgary
  791. will be used (if it exists). If you choose 'n', Calgary will not be
  792. used even if it exists. If you choose 'n' and would like to use
  793. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  794. If unsure, say Y.
  795. config MAXSMP
  796. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  797. depends on X86_64 && SMP && DEBUG_KERNEL
  798. select CPUMASK_OFFSTACK
  799. ---help---
  800. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  801. If unsure, say N.
  802. #
  803. # The maximum number of CPUs supported:
  804. #
  805. # The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
  806. # and which can be configured interactively in the
  807. # [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
  808. #
  809. # The ranges are different on 32-bit and 64-bit kernels, depending on
  810. # hardware capabilities and scalability features of the kernel.
  811. #
  812. # ( If MAXSMP is enabled we just use the highest possible value and disable
  813. # interactive configuration. )
  814. #
  815. config NR_CPUS_RANGE_BEGIN
  816. int
  817. default NR_CPUS_RANGE_END if MAXSMP
  818. default 1 if !SMP
  819. default 2
  820. config NR_CPUS_RANGE_END
  821. int
  822. depends on X86_32
  823. default 64 if SMP && X86_BIGSMP
  824. default 8 if SMP && !X86_BIGSMP
  825. default 1 if !SMP
  826. config NR_CPUS_RANGE_END
  827. int
  828. depends on X86_64
  829. default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
  830. default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
  831. default 1 if !SMP
  832. config NR_CPUS_DEFAULT
  833. int
  834. depends on X86_32
  835. default 32 if X86_BIGSMP
  836. default 8 if SMP
  837. default 1 if !SMP
  838. config NR_CPUS_DEFAULT
  839. int
  840. depends on X86_64
  841. default 8192 if MAXSMP
  842. default 64 if SMP
  843. default 1 if !SMP
  844. config NR_CPUS
  845. int "Maximum number of CPUs" if SMP && !MAXSMP
  846. range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
  847. default NR_CPUS_DEFAULT
  848. ---help---
  849. This allows you to specify the maximum number of CPUs which this
  850. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  851. supported value is 8192, otherwise the maximum value is 512. The
  852. minimum value which makes sense is 2.
  853. This is purely to save memory: each supported CPU adds about 8KB
  854. to the kernel image.
  855. config SCHED_SMT
  856. bool "SMT (Hyperthreading) scheduler support"
  857. depends on SMP
  858. ---help---
  859. SMT scheduler support improves the CPU scheduler's decision making
  860. when dealing with Intel Pentium 4 chips with HyperThreading at a
  861. cost of slightly increased overhead in some places. If unsure say
  862. N here.
  863. config SCHED_MC
  864. def_bool y
  865. prompt "Multi-core scheduler support"
  866. depends on SMP
  867. ---help---
  868. Multi-core scheduler support improves the CPU scheduler's decision
  869. making when dealing with multi-core CPU chips at a cost of slightly
  870. increased overhead in some places. If unsure say N here.
  871. config SCHED_MC_PRIO
  872. bool "CPU core priorities scheduler support"
  873. depends on SCHED_MC && CPU_SUP_INTEL
  874. select X86_INTEL_PSTATE
  875. select CPU_FREQ
  876. default y
  877. ---help---
  878. Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
  879. core ordering determined at manufacturing time, which allows
  880. certain cores to reach higher turbo frequencies (when running
  881. single threaded workloads) than others.
  882. Enabling this kernel feature teaches the scheduler about
  883. the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
  884. scheduler's CPU selection logic accordingly, so that higher
  885. overall system performance can be achieved.
  886. This feature will have no effect on CPUs without this feature.
  887. If unsure say Y here.
  888. source "kernel/Kconfig.preempt"
  889. config UP_LATE_INIT
  890. def_bool y
  891. depends on !SMP && X86_LOCAL_APIC
  892. config X86_UP_APIC
  893. bool "Local APIC support on uniprocessors" if !PCI_MSI
  894. default PCI_MSI
  895. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  896. ---help---
  897. A local APIC (Advanced Programmable Interrupt Controller) is an
  898. integrated interrupt controller in the CPU. If you have a single-CPU
  899. system which has a processor with a local APIC, you can say Y here to
  900. enable and use it. If you say Y here even though your machine doesn't
  901. have a local APIC, then the kernel will still run with no slowdown at
  902. all. The local APIC supports CPU-generated self-interrupts (timer,
  903. performance counters), and the NMI watchdog which detects hard
  904. lockups.
  905. config X86_UP_IOAPIC
  906. bool "IO-APIC support on uniprocessors"
  907. depends on X86_UP_APIC
  908. ---help---
  909. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  910. SMP-capable replacement for PC-style interrupt controllers. Most
  911. SMP systems and many recent uniprocessor systems have one.
  912. If you have a single-CPU system with an IO-APIC, you can say Y here
  913. to use it. If you say Y here even though your machine doesn't have
  914. an IO-APIC, then the kernel will still run with no slowdown at all.
  915. config X86_LOCAL_APIC
  916. def_bool y
  917. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  918. select IRQ_DOMAIN_HIERARCHY
  919. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  920. config X86_IO_APIC
  921. def_bool y
  922. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  923. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  924. bool "Reroute for broken boot IRQs"
  925. depends on X86_IO_APIC
  926. ---help---
  927. This option enables a workaround that fixes a source of
  928. spurious interrupts. This is recommended when threaded
  929. interrupt handling is used on systems where the generation of
  930. superfluous "boot interrupts" cannot be disabled.
  931. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  932. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  933. kernel does during interrupt handling). On chipsets where this
  934. boot IRQ generation cannot be disabled, this workaround keeps
  935. the original IRQ line masked so that only the equivalent "boot
  936. IRQ" is delivered to the CPUs. The workaround also tells the
  937. kernel to set up the IRQ handler on the boot IRQ line. In this
  938. way only one interrupt is delivered to the kernel. Otherwise
  939. the spurious second interrupt may cause the kernel to bring
  940. down (vital) interrupt lines.
  941. Only affects "broken" chipsets. Interrupt sharing may be
  942. increased on these systems.
  943. config X86_MCE
  944. bool "Machine Check / overheating reporting"
  945. select GENERIC_ALLOCATOR
  946. default y
  947. ---help---
  948. Machine Check support allows the processor to notify the
  949. kernel if it detects a problem (e.g. overheating, data corruption).
  950. The action the kernel takes depends on the severity of the problem,
  951. ranging from warning messages to halting the machine.
  952. config X86_MCELOG_LEGACY
  953. bool "Support for deprecated /dev/mcelog character device"
  954. depends on X86_MCE
  955. ---help---
  956. Enable support for /dev/mcelog which is needed by the old mcelog
  957. userspace logging daemon. Consider switching to the new generation
  958. rasdaemon solution.
  959. config X86_MCE_INTEL
  960. def_bool y
  961. prompt "Intel MCE features"
  962. depends on X86_MCE && X86_LOCAL_APIC
  963. ---help---
  964. Additional support for intel specific MCE features such as
  965. the thermal monitor.
  966. config X86_MCE_AMD
  967. def_bool y
  968. prompt "AMD MCE features"
  969. depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
  970. ---help---
  971. Additional support for AMD specific MCE features such as
  972. the DRAM Error Threshold.
  973. config X86_ANCIENT_MCE
  974. bool "Support for old Pentium 5 / WinChip machine checks"
  975. depends on X86_32 && X86_MCE
  976. ---help---
  977. Include support for machine check handling on old Pentium 5 or WinChip
  978. systems. These typically need to be enabled explicitly on the command
  979. line.
  980. config X86_MCE_THRESHOLD
  981. depends on X86_MCE_AMD || X86_MCE_INTEL
  982. def_bool y
  983. config X86_MCE_INJECT
  984. depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
  985. tristate "Machine check injector support"
  986. ---help---
  987. Provide support for injecting machine checks for testing purposes.
  988. If you don't know what a machine check is and you don't do kernel
  989. QA it is safe to say n.
  990. config X86_THERMAL_VECTOR
  991. def_bool y
  992. depends on X86_MCE_INTEL
  993. source "arch/x86/events/Kconfig"
  994. config X86_LEGACY_VM86
  995. bool "Legacy VM86 support"
  996. default n
  997. depends on X86_32
  998. ---help---
  999. This option allows user programs to put the CPU into V8086
  1000. mode, which is an 80286-era approximation of 16-bit real mode.
  1001. Some very old versions of X and/or vbetool require this option
  1002. for user mode setting. Similarly, DOSEMU will use it if
  1003. available to accelerate real mode DOS programs. However, any
  1004. recent version of DOSEMU, X, or vbetool should be fully
  1005. functional even without kernel VM86 support, as they will all
  1006. fall back to software emulation. Nevertheless, if you are using
  1007. a 16-bit DOS program where 16-bit performance matters, vm86
  1008. mode might be faster than emulation and you might want to
  1009. enable this option.
  1010. Note that any app that works on a 64-bit kernel is unlikely to
  1011. need this option, as 64-bit kernels don't, and can't, support
  1012. V8086 mode. This option is also unrelated to 16-bit protected
  1013. mode and is not needed to run most 16-bit programs under Wine.
  1014. Enabling this option increases the complexity of the kernel
  1015. and slows down exception handling a tiny bit.
  1016. If unsure, say N here.
  1017. config VM86
  1018. bool
  1019. default X86_LEGACY_VM86
  1020. config X86_16BIT
  1021. bool "Enable support for 16-bit segments" if EXPERT
  1022. default y
  1023. depends on MODIFY_LDT_SYSCALL
  1024. ---help---
  1025. This option is required by programs like Wine to run 16-bit
  1026. protected mode legacy code on x86 processors. Disabling
  1027. this option saves about 300 bytes on i386, or around 6K text
  1028. plus 16K runtime memory on x86-64,
  1029. config X86_ESPFIX32
  1030. def_bool y
  1031. depends on X86_16BIT && X86_32
  1032. config X86_ESPFIX64
  1033. def_bool y
  1034. depends on X86_16BIT && X86_64
  1035. config X86_VSYSCALL_EMULATION
  1036. bool "Enable vsyscall emulation" if EXPERT
  1037. default y
  1038. depends on X86_64
  1039. ---help---
  1040. This enables emulation of the legacy vsyscall page. Disabling
  1041. it is roughly equivalent to booting with vsyscall=none, except
  1042. that it will also disable the helpful warning if a program
  1043. tries to use a vsyscall. With this option set to N, offending
  1044. programs will just segfault, citing addresses of the form
  1045. 0xffffffffff600?00.
  1046. This option is required by many programs built before 2013, and
  1047. care should be used even with newer programs if set to N.
  1048. Disabling this option saves about 7K of kernel size and
  1049. possibly 4K of additional runtime pagetable memory.
  1050. config TOSHIBA
  1051. tristate "Toshiba Laptop support"
  1052. depends on X86_32
  1053. ---help---
  1054. This adds a driver to safely access the System Management Mode of
  1055. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  1056. not work on models with a Phoenix BIOS. The System Management Mode
  1057. is used to set the BIOS and power saving options on Toshiba portables.
  1058. For information on utilities to make use of this driver see the
  1059. Toshiba Linux utilities web site at:
  1060. <http://www.buzzard.org.uk/toshiba/>.
  1061. Say Y if you intend to run this kernel on a Toshiba portable.
  1062. Say N otherwise.
  1063. config I8K
  1064. tristate "Dell i8k legacy laptop support"
  1065. select HWMON
  1066. select SENSORS_DELL_SMM
  1067. ---help---
  1068. This option enables legacy /proc/i8k userspace interface in hwmon
  1069. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  1070. temperature and allows controlling fan speeds of Dell laptops via
  1071. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  1072. it reports also power and hotkey status. For fan speed control is
  1073. needed userspace package i8kutils.
  1074. Say Y if you intend to run this kernel on old Dell laptops or want to
  1075. use userspace package i8kutils.
  1076. Say N otherwise.
  1077. config X86_REBOOTFIXUPS
  1078. bool "Enable X86 board specific fixups for reboot"
  1079. depends on X86_32
  1080. ---help---
  1081. This enables chipset and/or board specific fixups to be done
  1082. in order to get reboot to work correctly. This is only needed on
  1083. some combinations of hardware and BIOS. The symptom, for which
  1084. this config is intended, is when reboot ends with a stalled/hung
  1085. system.
  1086. Currently, the only fixup is for the Geode machines using
  1087. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  1088. Say Y if you want to enable the fixup. Currently, it's safe to
  1089. enable this option even if you don't need it.
  1090. Say N otherwise.
  1091. config MICROCODE
  1092. bool "CPU microcode loading support"
  1093. default y
  1094. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  1095. select FW_LOADER
  1096. ---help---
  1097. If you say Y here, you will be able to update the microcode on
  1098. Intel and AMD processors. The Intel support is for the IA32 family,
  1099. e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
  1100. AMD support is for families 0x10 and later. You will obviously need
  1101. the actual microcode binary data itself which is not shipped with
  1102. the Linux kernel.
  1103. The preferred method to load microcode from a detached initrd is described
  1104. in Documentation/x86/microcode.txt. For that you need to enable
  1105. CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
  1106. initrd for microcode blobs.
  1107. In addition, you can build the microcode into the kernel. For that you
  1108. need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
  1109. config option.
  1110. config MICROCODE_INTEL
  1111. bool "Intel microcode loading support"
  1112. depends on MICROCODE
  1113. default MICROCODE
  1114. select FW_LOADER
  1115. ---help---
  1116. This options enables microcode patch loading support for Intel
  1117. processors.
  1118. For the current Intel microcode data package go to
  1119. <https://downloadcenter.intel.com> and search for
  1120. 'Linux Processor Microcode Data File'.
  1121. config MICROCODE_AMD
  1122. bool "AMD microcode loading support"
  1123. depends on MICROCODE
  1124. select FW_LOADER
  1125. ---help---
  1126. If you select this option, microcode patch loading support for AMD
  1127. processors will be enabled.
  1128. config MICROCODE_OLD_INTERFACE
  1129. def_bool y
  1130. depends on MICROCODE
  1131. config X86_MSR
  1132. tristate "/dev/cpu/*/msr - Model-specific register support"
  1133. ---help---
  1134. This device gives privileged processes access to the x86
  1135. Model-Specific Registers (MSRs). It is a character device with
  1136. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1137. MSR accesses are directed to a specific CPU on multi-processor
  1138. systems.
  1139. config X86_CPUID
  1140. tristate "/dev/cpu/*/cpuid - CPU information support"
  1141. ---help---
  1142. This device gives processes access to the x86 CPUID instruction to
  1143. be executed on a specific processor. It is a character device
  1144. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1145. /dev/cpu/31/cpuid.
  1146. choice
  1147. prompt "High Memory Support"
  1148. default HIGHMEM4G
  1149. depends on X86_32
  1150. config NOHIGHMEM
  1151. bool "off"
  1152. ---help---
  1153. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1154. However, the address space of 32-bit x86 processors is only 4
  1155. Gigabytes large. That means that, if you have a large amount of
  1156. physical memory, not all of it can be "permanently mapped" by the
  1157. kernel. The physical memory that's not permanently mapped is called
  1158. "high memory".
  1159. If you are compiling a kernel which will never run on a machine with
  1160. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1161. choice and suitable for most users). This will result in a "3GB/1GB"
  1162. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1163. space and the remaining part of the 4GB virtual memory space is used
  1164. by the kernel to permanently map as much physical memory as
  1165. possible.
  1166. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1167. answer "4GB" here.
  1168. If more than 4 Gigabytes is used then answer "64GB" here. This
  1169. selection turns Intel PAE (Physical Address Extension) mode on.
  1170. PAE implements 3-level paging on IA32 processors. PAE is fully
  1171. supported by Linux, PAE mode is implemented on all recent Intel
  1172. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1173. then the kernel will not boot on CPUs that don't support PAE!
  1174. The actual amount of total physical memory will either be
  1175. auto detected or can be forced by using a kernel command line option
  1176. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1177. your boot loader (lilo or loadlin) about how to pass options to the
  1178. kernel at boot time.)
  1179. If unsure, say "off".
  1180. config HIGHMEM4G
  1181. bool "4GB"
  1182. ---help---
  1183. Select this if you have a 32-bit processor and between 1 and 4
  1184. gigabytes of physical RAM.
  1185. config HIGHMEM64G
  1186. bool "64GB"
  1187. depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
  1188. select X86_PAE
  1189. ---help---
  1190. Select this if you have a 32-bit processor and more than 4
  1191. gigabytes of physical RAM.
  1192. endchoice
  1193. choice
  1194. prompt "Memory split" if EXPERT
  1195. default VMSPLIT_3G
  1196. depends on X86_32
  1197. ---help---
  1198. Select the desired split between kernel and user memory.
  1199. If the address range available to the kernel is less than the
  1200. physical memory installed, the remaining memory will be available
  1201. as "high memory". Accessing high memory is a little more costly
  1202. than low memory, as it needs to be mapped into the kernel first.
  1203. Note that increasing the kernel address space limits the range
  1204. available to user programs, making the address space there
  1205. tighter. Selecting anything other than the default 3G/1G split
  1206. will also likely make your kernel incompatible with binary-only
  1207. kernel modules.
  1208. If you are not absolutely sure what you are doing, leave this
  1209. option alone!
  1210. config VMSPLIT_3G
  1211. bool "3G/1G user/kernel split"
  1212. config VMSPLIT_3G_OPT
  1213. depends on !X86_PAE
  1214. bool "3G/1G user/kernel split (for full 1G low memory)"
  1215. config VMSPLIT_2G
  1216. bool "2G/2G user/kernel split"
  1217. config VMSPLIT_2G_OPT
  1218. depends on !X86_PAE
  1219. bool "2G/2G user/kernel split (for full 2G low memory)"
  1220. config VMSPLIT_1G
  1221. bool "1G/3G user/kernel split"
  1222. endchoice
  1223. config PAGE_OFFSET
  1224. hex
  1225. default 0xB0000000 if VMSPLIT_3G_OPT
  1226. default 0x80000000 if VMSPLIT_2G
  1227. default 0x78000000 if VMSPLIT_2G_OPT
  1228. default 0x40000000 if VMSPLIT_1G
  1229. default 0xC0000000
  1230. depends on X86_32
  1231. config HIGHMEM
  1232. def_bool y
  1233. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1234. config X86_PAE
  1235. bool "PAE (Physical Address Extension) Support"
  1236. depends on X86_32 && !HIGHMEM4G
  1237. select PHYS_ADDR_T_64BIT
  1238. select SWIOTLB
  1239. ---help---
  1240. PAE is required for NX support, and furthermore enables
  1241. larger swapspace support for non-overcommit purposes. It
  1242. has the cost of more pagetable lookup overhead, and also
  1243. consumes more pagetable space per process.
  1244. config X86_5LEVEL
  1245. bool "Enable 5-level page tables support"
  1246. select DYNAMIC_MEMORY_LAYOUT
  1247. select SPARSEMEM_VMEMMAP
  1248. depends on X86_64
  1249. ---help---
  1250. 5-level paging enables access to larger address space:
  1251. upto 128 PiB of virtual address space and 4 PiB of
  1252. physical address space.
  1253. It will be supported by future Intel CPUs.
  1254. A kernel with the option enabled can be booted on machines that
  1255. support 4- or 5-level paging.
  1256. See Documentation/x86/x86_64/5level-paging.txt for more
  1257. information.
  1258. Say N if unsure.
  1259. config X86_DIRECT_GBPAGES
  1260. def_bool y
  1261. depends on X86_64 && !DEBUG_PAGEALLOC
  1262. ---help---
  1263. Certain kernel features effectively disable kernel
  1264. linear 1 GB mappings (even if the CPU otherwise
  1265. supports them), so don't confuse the user by printing
  1266. that we have them enabled.
  1267. config ARCH_HAS_MEM_ENCRYPT
  1268. def_bool y
  1269. config AMD_MEM_ENCRYPT
  1270. bool "AMD Secure Memory Encryption (SME) support"
  1271. depends on X86_64 && CPU_SUP_AMD
  1272. ---help---
  1273. Say yes to enable support for the encryption of system memory.
  1274. This requires an AMD processor that supports Secure Memory
  1275. Encryption (SME).
  1276. config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
  1277. bool "Activate AMD Secure Memory Encryption (SME) by default"
  1278. default y
  1279. depends on AMD_MEM_ENCRYPT
  1280. ---help---
  1281. Say yes to have system memory encrypted by default if running on
  1282. an AMD processor that supports Secure Memory Encryption (SME).
  1283. If set to Y, then the encryption of system memory can be
  1284. deactivated with the mem_encrypt=off command line option.
  1285. If set to N, then the encryption of system memory can be
  1286. activated with the mem_encrypt=on command line option.
  1287. config ARCH_USE_MEMREMAP_PROT
  1288. def_bool y
  1289. depends on AMD_MEM_ENCRYPT
  1290. # Common NUMA Features
  1291. config NUMA
  1292. bool "Numa Memory Allocation and Scheduler Support"
  1293. depends on SMP
  1294. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1295. default y if X86_BIGSMP
  1296. ---help---
  1297. Enable NUMA (Non Uniform Memory Access) support.
  1298. The kernel will try to allocate memory used by a CPU on the
  1299. local memory controller of the CPU and add some more
  1300. NUMA awareness to the kernel.
  1301. For 64-bit this is recommended if the system is Intel Core i7
  1302. (or later), AMD Opteron, or EM64T NUMA.
  1303. For 32-bit this is only needed if you boot a 32-bit
  1304. kernel on a 64-bit NUMA platform.
  1305. Otherwise, you should say N.
  1306. config AMD_NUMA
  1307. def_bool y
  1308. prompt "Old style AMD Opteron NUMA detection"
  1309. depends on X86_64 && NUMA && PCI
  1310. ---help---
  1311. Enable AMD NUMA node topology detection. You should say Y here if
  1312. you have a multi processor AMD system. This uses an old method to
  1313. read the NUMA configuration directly from the builtin Northbridge
  1314. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1315. which also takes priority if both are compiled in.
  1316. config X86_64_ACPI_NUMA
  1317. def_bool y
  1318. prompt "ACPI NUMA detection"
  1319. depends on X86_64 && NUMA && ACPI && PCI
  1320. select ACPI_NUMA
  1321. ---help---
  1322. Enable ACPI SRAT based node topology detection.
  1323. # Some NUMA nodes have memory ranges that span
  1324. # other nodes. Even though a pfn is valid and
  1325. # between a node's start and end pfns, it may not
  1326. # reside on that node. See memmap_init_zone()
  1327. # for details.
  1328. config NODES_SPAN_OTHER_NODES
  1329. def_bool y
  1330. depends on X86_64_ACPI_NUMA
  1331. config NUMA_EMU
  1332. bool "NUMA emulation"
  1333. depends on NUMA
  1334. ---help---
  1335. Enable NUMA emulation. A flat machine will be split
  1336. into virtual nodes when booted with "numa=fake=N", where N is the
  1337. number of nodes. This is only useful for debugging.
  1338. config NODES_SHIFT
  1339. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1340. range 1 10
  1341. default "10" if MAXSMP
  1342. default "6" if X86_64
  1343. default "3"
  1344. depends on NEED_MULTIPLE_NODES
  1345. ---help---
  1346. Specify the maximum number of NUMA Nodes available on the target
  1347. system. Increases memory reserved to accommodate various tables.
  1348. config ARCH_HAVE_MEMORY_PRESENT
  1349. def_bool y
  1350. depends on X86_32 && DISCONTIGMEM
  1351. config ARCH_FLATMEM_ENABLE
  1352. def_bool y
  1353. depends on X86_32 && !NUMA
  1354. config ARCH_DISCONTIGMEM_ENABLE
  1355. def_bool y
  1356. depends on NUMA && X86_32
  1357. config ARCH_DISCONTIGMEM_DEFAULT
  1358. def_bool y
  1359. depends on NUMA && X86_32
  1360. config ARCH_SPARSEMEM_ENABLE
  1361. def_bool y
  1362. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1363. select SPARSEMEM_STATIC if X86_32
  1364. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1365. config ARCH_SPARSEMEM_DEFAULT
  1366. def_bool y
  1367. depends on X86_64
  1368. config ARCH_SELECT_MEMORY_MODEL
  1369. def_bool y
  1370. depends on ARCH_SPARSEMEM_ENABLE
  1371. config ARCH_MEMORY_PROBE
  1372. bool "Enable sysfs memory/probe interface"
  1373. depends on X86_64 && MEMORY_HOTPLUG
  1374. help
  1375. This option enables a sysfs memory/probe interface for testing.
  1376. See Documentation/memory-hotplug.txt for more information.
  1377. If you are unsure how to answer this question, answer N.
  1378. config ARCH_PROC_KCORE_TEXT
  1379. def_bool y
  1380. depends on X86_64 && PROC_KCORE
  1381. config ILLEGAL_POINTER_VALUE
  1382. hex
  1383. default 0 if X86_32
  1384. default 0xdead000000000000 if X86_64
  1385. source "mm/Kconfig"
  1386. config X86_PMEM_LEGACY_DEVICE
  1387. bool
  1388. config X86_PMEM_LEGACY
  1389. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1390. depends on PHYS_ADDR_T_64BIT
  1391. depends on BLK_DEV
  1392. select X86_PMEM_LEGACY_DEVICE
  1393. select LIBNVDIMM
  1394. help
  1395. Treat memory marked using the non-standard e820 type of 12 as used
  1396. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1397. The kernel will offer these regions to the 'pmem' driver so
  1398. they can be used for persistent storage.
  1399. Say Y if unsure.
  1400. config HIGHPTE
  1401. bool "Allocate 3rd-level pagetables from highmem"
  1402. depends on HIGHMEM
  1403. ---help---
  1404. The VM uses one page table entry for each page of physical memory.
  1405. For systems with a lot of RAM, this can be wasteful of precious
  1406. low memory. Setting this option will put user-space page table
  1407. entries in high memory.
  1408. config X86_CHECK_BIOS_CORRUPTION
  1409. bool "Check for low memory corruption"
  1410. ---help---
  1411. Periodically check for memory corruption in low memory, which
  1412. is suspected to be caused by BIOS. Even when enabled in the
  1413. configuration, it is disabled at runtime. Enable it by
  1414. setting "memory_corruption_check=1" on the kernel command
  1415. line. By default it scans the low 64k of memory every 60
  1416. seconds; see the memory_corruption_check_size and
  1417. memory_corruption_check_period parameters in
  1418. Documentation/admin-guide/kernel-parameters.rst to adjust this.
  1419. When enabled with the default parameters, this option has
  1420. almost no overhead, as it reserves a relatively small amount
  1421. of memory and scans it infrequently. It both detects corruption
  1422. and prevents it from affecting the running system.
  1423. It is, however, intended as a diagnostic tool; if repeatable
  1424. BIOS-originated corruption always affects the same memory,
  1425. you can use memmap= to prevent the kernel from using that
  1426. memory.
  1427. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1428. bool "Set the default setting of memory_corruption_check"
  1429. depends on X86_CHECK_BIOS_CORRUPTION
  1430. default y
  1431. ---help---
  1432. Set whether the default state of memory_corruption_check is
  1433. on or off.
  1434. config X86_RESERVE_LOW
  1435. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1436. default 64
  1437. range 4 640
  1438. ---help---
  1439. Specify the amount of low memory to reserve for the BIOS.
  1440. The first page contains BIOS data structures that the kernel
  1441. must not use, so that page must always be reserved.
  1442. By default we reserve the first 64K of physical RAM, as a
  1443. number of BIOSes are known to corrupt that memory range
  1444. during events such as suspend/resume or monitor cable
  1445. insertion, so it must not be used by the kernel.
  1446. You can set this to 4 if you are absolutely sure that you
  1447. trust the BIOS to get all its memory reservations and usages
  1448. right. If you know your BIOS have problems beyond the
  1449. default 64K area, you can set this to 640 to avoid using the
  1450. entire low memory range.
  1451. If you have doubts about the BIOS (e.g. suspend/resume does
  1452. not work or there's kernel crashes after certain hardware
  1453. hotplug events) then you might want to enable
  1454. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1455. typical corruption patterns.
  1456. Leave this to the default value of 64 if you are unsure.
  1457. config MATH_EMULATION
  1458. bool
  1459. depends on MODIFY_LDT_SYSCALL
  1460. prompt "Math emulation" if X86_32
  1461. ---help---
  1462. Linux can emulate a math coprocessor (used for floating point
  1463. operations) if you don't have one. 486DX and Pentium processors have
  1464. a math coprocessor built in, 486SX and 386 do not, unless you added
  1465. a 487DX or 387, respectively. (The messages during boot time can
  1466. give you some hints here ["man dmesg"].) Everyone needs either a
  1467. coprocessor or this emulation.
  1468. If you don't have a math coprocessor, you need to say Y here; if you
  1469. say Y here even though you have a coprocessor, the coprocessor will
  1470. be used nevertheless. (This behavior can be changed with the kernel
  1471. command line option "no387", which comes handy if your coprocessor
  1472. is broken. Try "man bootparam" or see the documentation of your boot
  1473. loader (lilo or loadlin) about how to pass options to the kernel at
  1474. boot time.) This means that it is a good idea to say Y here if you
  1475. intend to use this kernel on different machines.
  1476. More information about the internals of the Linux math coprocessor
  1477. emulation can be found in <file:arch/x86/math-emu/README>.
  1478. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1479. kernel, it won't hurt.
  1480. config MTRR
  1481. def_bool y
  1482. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1483. ---help---
  1484. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1485. the Memory Type Range Registers (MTRRs) may be used to control
  1486. processor access to memory ranges. This is most useful if you have
  1487. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1488. allows bus write transfers to be combined into a larger transfer
  1489. before bursting over the PCI/AGP bus. This can increase performance
  1490. of image write operations 2.5 times or more. Saying Y here creates a
  1491. /proc/mtrr file which may be used to manipulate your processor's
  1492. MTRRs. Typically the X server should use this.
  1493. This code has a reasonably generic interface so that similar
  1494. control registers on other processors can be easily supported
  1495. as well:
  1496. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1497. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1498. these, the ARRs are used to emulate the MTRRs.
  1499. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1500. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1501. write-combining. All of these processors are supported by this code
  1502. and it makes sense to say Y here if you have one of them.
  1503. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1504. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1505. can lead to all sorts of problems, so it's good to say Y here.
  1506. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1507. just add about 9 KB to your kernel.
  1508. See <file:Documentation/x86/mtrr.txt> for more information.
  1509. config MTRR_SANITIZER
  1510. def_bool y
  1511. prompt "MTRR cleanup support"
  1512. depends on MTRR
  1513. ---help---
  1514. Convert MTRR layout from continuous to discrete, so X drivers can
  1515. add writeback entries.
  1516. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1517. The largest mtrr entry size for a continuous block can be set with
  1518. mtrr_chunk_size.
  1519. If unsure, say Y.
  1520. config MTRR_SANITIZER_ENABLE_DEFAULT
  1521. int "MTRR cleanup enable value (0-1)"
  1522. range 0 1
  1523. default "0"
  1524. depends on MTRR_SANITIZER
  1525. ---help---
  1526. Enable mtrr cleanup default value
  1527. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1528. int "MTRR cleanup spare reg num (0-7)"
  1529. range 0 7
  1530. default "1"
  1531. depends on MTRR_SANITIZER
  1532. ---help---
  1533. mtrr cleanup spare entries default, it can be changed via
  1534. mtrr_spare_reg_nr=N on the kernel command line.
  1535. config X86_PAT
  1536. def_bool y
  1537. prompt "x86 PAT support" if EXPERT
  1538. depends on MTRR
  1539. ---help---
  1540. Use PAT attributes to setup page level cache control.
  1541. PATs are the modern equivalents of MTRRs and are much more
  1542. flexible than MTRRs.
  1543. Say N here if you see bootup problems (boot crash, boot hang,
  1544. spontaneous reboots) or a non-working video driver.
  1545. If unsure, say Y.
  1546. config ARCH_USES_PG_UNCACHED
  1547. def_bool y
  1548. depends on X86_PAT
  1549. config ARCH_RANDOM
  1550. def_bool y
  1551. prompt "x86 architectural random number generator" if EXPERT
  1552. ---help---
  1553. Enable the x86 architectural RDRAND instruction
  1554. (Intel Bull Mountain technology) to generate random numbers.
  1555. If supported, this is a high bandwidth, cryptographically
  1556. secure hardware random number generator.
  1557. config X86_SMAP
  1558. def_bool y
  1559. prompt "Supervisor Mode Access Prevention" if EXPERT
  1560. ---help---
  1561. Supervisor Mode Access Prevention (SMAP) is a security
  1562. feature in newer Intel processors. There is a small
  1563. performance cost if this enabled and turned on; there is
  1564. also a small increase in the kernel size if this is enabled.
  1565. If unsure, say Y.
  1566. config X86_INTEL_UMIP
  1567. def_bool y
  1568. depends on CPU_SUP_INTEL
  1569. prompt "Intel User Mode Instruction Prevention" if EXPERT
  1570. ---help---
  1571. The User Mode Instruction Prevention (UMIP) is a security
  1572. feature in newer Intel processors. If enabled, a general
  1573. protection fault is issued if the SGDT, SLDT, SIDT, SMSW
  1574. or STR instructions are executed in user mode. These instructions
  1575. unnecessarily expose information about the hardware state.
  1576. The vast majority of applications do not use these instructions.
  1577. For the very few that do, software emulation is provided in
  1578. specific cases in protected and virtual-8086 modes. Emulated
  1579. results are dummy.
  1580. config X86_INTEL_MPX
  1581. prompt "Intel MPX (Memory Protection Extensions)"
  1582. def_bool n
  1583. # Note: only available in 64-bit mode due to VMA flags shortage
  1584. depends on CPU_SUP_INTEL && X86_64
  1585. select ARCH_USES_HIGH_VMA_FLAGS
  1586. ---help---
  1587. MPX provides hardware features that can be used in
  1588. conjunction with compiler-instrumented code to check
  1589. memory references. It is designed to detect buffer
  1590. overflow or underflow bugs.
  1591. This option enables running applications which are
  1592. instrumented or otherwise use MPX. It does not use MPX
  1593. itself inside the kernel or to protect the kernel
  1594. against bad memory references.
  1595. Enabling this option will make the kernel larger:
  1596. ~8k of kernel text and 36 bytes of data on a 64-bit
  1597. defconfig. It adds a long to the 'mm_struct' which
  1598. will increase the kernel memory overhead of each
  1599. process and adds some branches to paths used during
  1600. exec() and munmap().
  1601. For details, see Documentation/x86/intel_mpx.txt
  1602. If unsure, say N.
  1603. config X86_INTEL_MEMORY_PROTECTION_KEYS
  1604. prompt "Intel Memory Protection Keys"
  1605. def_bool y
  1606. # Note: only available in 64-bit mode
  1607. depends on CPU_SUP_INTEL && X86_64
  1608. select ARCH_USES_HIGH_VMA_FLAGS
  1609. select ARCH_HAS_PKEYS
  1610. ---help---
  1611. Memory Protection Keys provides a mechanism for enforcing
  1612. page-based protections, but without requiring modification of the
  1613. page tables when an application changes protection domains.
  1614. For details, see Documentation/x86/protection-keys.txt
  1615. If unsure, say y.
  1616. config EFI
  1617. bool "EFI runtime service support"
  1618. depends on ACPI
  1619. select UCS2_STRING
  1620. select EFI_RUNTIME_WRAPPERS
  1621. ---help---
  1622. This enables the kernel to use EFI runtime services that are
  1623. available (such as the EFI variable services).
  1624. This option is only useful on systems that have EFI firmware.
  1625. In addition, you should use the latest ELILO loader available
  1626. at <http://elilo.sourceforge.net> in order to take advantage
  1627. of EFI runtime services. However, even with this option, the
  1628. resultant kernel should continue to boot on existing non-EFI
  1629. platforms.
  1630. config EFI_STUB
  1631. bool "EFI stub support"
  1632. depends on EFI && !X86_USE_3DNOW
  1633. select RELOCATABLE
  1634. ---help---
  1635. This kernel feature allows a bzImage to be loaded directly
  1636. by EFI firmware without the use of a bootloader.
  1637. See Documentation/efi-stub.txt for more information.
  1638. config EFI_MIXED
  1639. bool "EFI mixed-mode support"
  1640. depends on EFI_STUB && X86_64
  1641. ---help---
  1642. Enabling this feature allows a 64-bit kernel to be booted
  1643. on a 32-bit firmware, provided that your CPU supports 64-bit
  1644. mode.
  1645. Note that it is not possible to boot a mixed-mode enabled
  1646. kernel via the EFI boot stub - a bootloader that supports
  1647. the EFI handover protocol must be used.
  1648. If unsure, say N.
  1649. config SECCOMP
  1650. def_bool y
  1651. prompt "Enable seccomp to safely compute untrusted bytecode"
  1652. ---help---
  1653. This kernel feature is useful for number crunching applications
  1654. that may need to compute untrusted bytecode during their
  1655. execution. By using pipes or other transports made available to
  1656. the process as file descriptors supporting the read/write
  1657. syscalls, it's possible to isolate those applications in
  1658. their own address space using seccomp. Once seccomp is
  1659. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1660. and the task is only allowed to execute a few safe syscalls
  1661. defined by each seccomp mode.
  1662. If unsure, say Y. Only embedded should say N here.
  1663. source kernel/Kconfig.hz
  1664. config KEXEC
  1665. bool "kexec system call"
  1666. select KEXEC_CORE
  1667. ---help---
  1668. kexec is a system call that implements the ability to shutdown your
  1669. current kernel, and to start another kernel. It is like a reboot
  1670. but it is independent of the system firmware. And like a reboot
  1671. you can start any kernel with it, not just Linux.
  1672. The name comes from the similarity to the exec system call.
  1673. It is an ongoing process to be certain the hardware in a machine
  1674. is properly shutdown, so do not be surprised if this code does not
  1675. initially work for you. As of this writing the exact hardware
  1676. interface is strongly in flux, so no good recommendation can be
  1677. made.
  1678. config KEXEC_FILE
  1679. bool "kexec file based system call"
  1680. select KEXEC_CORE
  1681. select BUILD_BIN2C
  1682. depends on X86_64
  1683. depends on CRYPTO=y
  1684. depends on CRYPTO_SHA256=y
  1685. ---help---
  1686. This is new version of kexec system call. This system call is
  1687. file based and takes file descriptors as system call argument
  1688. for kernel and initramfs as opposed to list of segments as
  1689. accepted by previous system call.
  1690. config ARCH_HAS_KEXEC_PURGATORY
  1691. def_bool KEXEC_FILE
  1692. config KEXEC_VERIFY_SIG
  1693. bool "Verify kernel signature during kexec_file_load() syscall"
  1694. depends on KEXEC_FILE
  1695. ---help---
  1696. This option makes kernel signature verification mandatory for
  1697. the kexec_file_load() syscall.
  1698. In addition to that option, you need to enable signature
  1699. verification for the corresponding kernel image type being
  1700. loaded in order for this to work.
  1701. config KEXEC_BZIMAGE_VERIFY_SIG
  1702. bool "Enable bzImage signature verification support"
  1703. depends on KEXEC_VERIFY_SIG
  1704. depends on SIGNED_PE_FILE_VERIFICATION
  1705. select SYSTEM_TRUSTED_KEYRING
  1706. ---help---
  1707. Enable bzImage signature verification support.
  1708. config CRASH_DUMP
  1709. bool "kernel crash dumps"
  1710. depends on X86_64 || (X86_32 && HIGHMEM)
  1711. ---help---
  1712. Generate crash dump after being started by kexec.
  1713. This should be normally only set in special crash dump kernels
  1714. which are loaded in the main kernel with kexec-tools into
  1715. a specially reserved region and then later executed after
  1716. a crash by kdump/kexec. The crash dump kernel must be compiled
  1717. to a memory address not used by the main kernel or BIOS using
  1718. PHYSICAL_START, or it must be built as a relocatable image
  1719. (CONFIG_RELOCATABLE=y).
  1720. For more details see Documentation/kdump/kdump.txt
  1721. config KEXEC_JUMP
  1722. bool "kexec jump"
  1723. depends on KEXEC && HIBERNATION
  1724. ---help---
  1725. Jump between original kernel and kexeced kernel and invoke
  1726. code in physical address mode via KEXEC
  1727. config PHYSICAL_START
  1728. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1729. default "0x1000000"
  1730. ---help---
  1731. This gives the physical address where the kernel is loaded.
  1732. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1733. bzImage will decompress itself to above physical address and
  1734. run from there. Otherwise, bzImage will run from the address where
  1735. it has been loaded by the boot loader and will ignore above physical
  1736. address.
  1737. In normal kdump cases one does not have to set/change this option
  1738. as now bzImage can be compiled as a completely relocatable image
  1739. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1740. address. This option is mainly useful for the folks who don't want
  1741. to use a bzImage for capturing the crash dump and want to use a
  1742. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1743. to be specifically compiled to run from a specific memory area
  1744. (normally a reserved region) and this option comes handy.
  1745. So if you are using bzImage for capturing the crash dump,
  1746. leave the value here unchanged to 0x1000000 and set
  1747. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1748. for capturing the crash dump change this value to start of
  1749. the reserved region. In other words, it can be set based on
  1750. the "X" value as specified in the "crashkernel=YM@XM"
  1751. command line boot parameter passed to the panic-ed
  1752. kernel. Please take a look at Documentation/kdump/kdump.txt
  1753. for more details about crash dumps.
  1754. Usage of bzImage for capturing the crash dump is recommended as
  1755. one does not have to build two kernels. Same kernel can be used
  1756. as production kernel and capture kernel. Above option should have
  1757. gone away after relocatable bzImage support is introduced. But it
  1758. is present because there are users out there who continue to use
  1759. vmlinux for dump capture. This option should go away down the
  1760. line.
  1761. Don't change this unless you know what you are doing.
  1762. config RELOCATABLE
  1763. bool "Build a relocatable kernel"
  1764. default y
  1765. ---help---
  1766. This builds a kernel image that retains relocation information
  1767. so it can be loaded someplace besides the default 1MB.
  1768. The relocations tend to make the kernel binary about 10% larger,
  1769. but are discarded at runtime.
  1770. One use is for the kexec on panic case where the recovery kernel
  1771. must live at a different physical address than the primary
  1772. kernel.
  1773. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1774. it has been loaded at and the compile time physical address
  1775. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1776. config RANDOMIZE_BASE
  1777. bool "Randomize the address of the kernel image (KASLR)"
  1778. depends on RELOCATABLE
  1779. default y
  1780. ---help---
  1781. In support of Kernel Address Space Layout Randomization (KASLR),
  1782. this randomizes the physical address at which the kernel image
  1783. is decompressed and the virtual address where the kernel
  1784. image is mapped, as a security feature that deters exploit
  1785. attempts relying on knowledge of the location of kernel
  1786. code internals.
  1787. On 64-bit, the kernel physical and virtual addresses are
  1788. randomized separately. The physical address will be anywhere
  1789. between 16MB and the top of physical memory (up to 64TB). The
  1790. virtual address will be randomized from 16MB up to 1GB (9 bits
  1791. of entropy). Note that this also reduces the memory space
  1792. available to kernel modules from 1.5GB to 1GB.
  1793. On 32-bit, the kernel physical and virtual addresses are
  1794. randomized together. They will be randomized from 16MB up to
  1795. 512MB (8 bits of entropy).
  1796. Entropy is generated using the RDRAND instruction if it is
  1797. supported. If RDTSC is supported, its value is mixed into
  1798. the entropy pool as well. If neither RDRAND nor RDTSC are
  1799. supported, then entropy is read from the i8254 timer. The
  1800. usable entropy is limited by the kernel being built using
  1801. 2GB addressing, and that PHYSICAL_ALIGN must be at a
  1802. minimum of 2MB. As a result, only 10 bits of entropy are
  1803. theoretically possible, but the implementations are further
  1804. limited due to memory layouts.
  1805. If unsure, say Y.
  1806. # Relocation on x86 needs some additional build support
  1807. config X86_NEED_RELOCS
  1808. def_bool y
  1809. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1810. config PHYSICAL_ALIGN
  1811. hex "Alignment value to which kernel should be aligned"
  1812. default "0x200000"
  1813. range 0x2000 0x1000000 if X86_32
  1814. range 0x200000 0x1000000 if X86_64
  1815. ---help---
  1816. This value puts the alignment restrictions on physical address
  1817. where kernel is loaded and run from. Kernel is compiled for an
  1818. address which meets above alignment restriction.
  1819. If bootloader loads the kernel at a non-aligned address and
  1820. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1821. address aligned to above value and run from there.
  1822. If bootloader loads the kernel at a non-aligned address and
  1823. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1824. load address and decompress itself to the address it has been
  1825. compiled for and run from there. The address for which kernel is
  1826. compiled already meets above alignment restrictions. Hence the
  1827. end result is that kernel runs from a physical address meeting
  1828. above alignment restrictions.
  1829. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1830. this value must be a multiple of 0x200000.
  1831. Don't change this unless you know what you are doing.
  1832. config DYNAMIC_MEMORY_LAYOUT
  1833. bool
  1834. ---help---
  1835. This option makes base addresses of vmalloc and vmemmap as well as
  1836. __PAGE_OFFSET movable during boot.
  1837. config RANDOMIZE_MEMORY
  1838. bool "Randomize the kernel memory sections"
  1839. depends on X86_64
  1840. depends on RANDOMIZE_BASE
  1841. select DYNAMIC_MEMORY_LAYOUT
  1842. default RANDOMIZE_BASE
  1843. ---help---
  1844. Randomizes the base virtual address of kernel memory sections
  1845. (physical memory mapping, vmalloc & vmemmap). This security feature
  1846. makes exploits relying on predictable memory locations less reliable.
  1847. The order of allocations remains unchanged. Entropy is generated in
  1848. the same way as RANDOMIZE_BASE. Current implementation in the optimal
  1849. configuration have in average 30,000 different possible virtual
  1850. addresses for each memory section.
  1851. If unsure, say Y.
  1852. config RANDOMIZE_MEMORY_PHYSICAL_PADDING
  1853. hex "Physical memory mapping padding" if EXPERT
  1854. depends on RANDOMIZE_MEMORY
  1855. default "0xa" if MEMORY_HOTPLUG
  1856. default "0x0"
  1857. range 0x1 0x40 if MEMORY_HOTPLUG
  1858. range 0x0 0x40
  1859. ---help---
  1860. Define the padding in terabytes added to the existing physical
  1861. memory size during kernel memory randomization. It is useful
  1862. for memory hotplug support but reduces the entropy available for
  1863. address randomization.
  1864. If unsure, leave at the default value.
  1865. config HOTPLUG_CPU
  1866. bool "Support for hot-pluggable CPUs"
  1867. depends on SMP
  1868. ---help---
  1869. Say Y here to allow turning CPUs off and on. CPUs can be
  1870. controlled through /sys/devices/system/cpu.
  1871. ( Note: power management support will enable this option
  1872. automatically on SMP systems. )
  1873. Say N if you want to disable CPU hotplug.
  1874. config BOOTPARAM_HOTPLUG_CPU0
  1875. bool "Set default setting of cpu0_hotpluggable"
  1876. default n
  1877. depends on HOTPLUG_CPU
  1878. ---help---
  1879. Set whether default state of cpu0_hotpluggable is on or off.
  1880. Say Y here to enable CPU0 hotplug by default. If this switch
  1881. is turned on, there is no need to give cpu0_hotplug kernel
  1882. parameter and the CPU0 hotplug feature is enabled by default.
  1883. Please note: there are two known CPU0 dependencies if you want
  1884. to enable the CPU0 hotplug feature either by this switch or by
  1885. cpu0_hotplug kernel parameter.
  1886. First, resume from hibernate or suspend always starts from CPU0.
  1887. So hibernate and suspend are prevented if CPU0 is offline.
  1888. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1889. offline if any interrupt can not migrate out of CPU0. There may
  1890. be other CPU0 dependencies.
  1891. Please make sure the dependencies are under your control before
  1892. you enable this feature.
  1893. Say N if you don't want to enable CPU0 hotplug feature by default.
  1894. You still can enable the CPU0 hotplug feature at boot by kernel
  1895. parameter cpu0_hotplug.
  1896. config DEBUG_HOTPLUG_CPU0
  1897. def_bool n
  1898. prompt "Debug CPU0 hotplug"
  1899. depends on HOTPLUG_CPU
  1900. ---help---
  1901. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1902. soon as possible and boots up userspace with CPU0 offlined. User
  1903. can online CPU0 back after boot time.
  1904. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1905. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1906. compilation or giving cpu0_hotplug kernel parameter at boot.
  1907. If unsure, say N.
  1908. config COMPAT_VDSO
  1909. def_bool n
  1910. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1911. depends on COMPAT_32
  1912. ---help---
  1913. Certain buggy versions of glibc will crash if they are
  1914. presented with a 32-bit vDSO that is not mapped at the address
  1915. indicated in its segment table.
  1916. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1917. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1918. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1919. the only released version with the bug, but OpenSUSE 9
  1920. contains a buggy "glibc 2.3.2".
  1921. The symptom of the bug is that everything crashes on startup, saying:
  1922. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1923. Saying Y here changes the default value of the vdso32 boot
  1924. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1925. This works around the glibc bug but hurts performance.
  1926. If unsure, say N: if you are compiling your own kernel, you
  1927. are unlikely to be using a buggy version of glibc.
  1928. choice
  1929. prompt "vsyscall table for legacy applications"
  1930. depends on X86_64
  1931. default LEGACY_VSYSCALL_EMULATE
  1932. help
  1933. Legacy user code that does not know how to find the vDSO expects
  1934. to be able to issue three syscalls by calling fixed addresses in
  1935. kernel space. Since this location is not randomized with ASLR,
  1936. it can be used to assist security vulnerability exploitation.
  1937. This setting can be changed at boot time via the kernel command
  1938. line parameter vsyscall=[emulate|none].
  1939. On a system with recent enough glibc (2.14 or newer) and no
  1940. static binaries, you can say None without a performance penalty
  1941. to improve security.
  1942. If unsure, select "Emulate".
  1943. config LEGACY_VSYSCALL_EMULATE
  1944. bool "Emulate"
  1945. help
  1946. The kernel traps and emulates calls into the fixed
  1947. vsyscall address mapping. This makes the mapping
  1948. non-executable, but it still contains known contents,
  1949. which could be used in certain rare security vulnerability
  1950. exploits. This configuration is recommended when userspace
  1951. still uses the vsyscall area.
  1952. config LEGACY_VSYSCALL_NONE
  1953. bool "None"
  1954. help
  1955. There will be no vsyscall mapping at all. This will
  1956. eliminate any risk of ASLR bypass due to the vsyscall
  1957. fixed address mapping. Attempts to use the vsyscalls
  1958. will be reported to dmesg, so that either old or
  1959. malicious userspace programs can be identified.
  1960. endchoice
  1961. config CMDLINE_BOOL
  1962. bool "Built-in kernel command line"
  1963. ---help---
  1964. Allow for specifying boot arguments to the kernel at
  1965. build time. On some systems (e.g. embedded ones), it is
  1966. necessary or convenient to provide some or all of the
  1967. kernel boot arguments with the kernel itself (that is,
  1968. to not rely on the boot loader to provide them.)
  1969. To compile command line arguments into the kernel,
  1970. set this option to 'Y', then fill in the
  1971. boot arguments in CONFIG_CMDLINE.
  1972. Systems with fully functional boot loaders (i.e. non-embedded)
  1973. should leave this option set to 'N'.
  1974. config CMDLINE
  1975. string "Built-in kernel command string"
  1976. depends on CMDLINE_BOOL
  1977. default ""
  1978. ---help---
  1979. Enter arguments here that should be compiled into the kernel
  1980. image and used at boot time. If the boot loader provides a
  1981. command line at boot time, it is appended to this string to
  1982. form the full kernel command line, when the system boots.
  1983. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1984. change this behavior.
  1985. In most cases, the command line (whether built-in or provided
  1986. by the boot loader) should specify the device for the root
  1987. file system.
  1988. config CMDLINE_OVERRIDE
  1989. bool "Built-in command line overrides boot loader arguments"
  1990. depends on CMDLINE_BOOL
  1991. ---help---
  1992. Set this option to 'Y' to have the kernel ignore the boot loader
  1993. command line, and use ONLY the built-in command line.
  1994. This is used to work around broken boot loaders. This should
  1995. be set to 'N' under normal conditions.
  1996. config MODIFY_LDT_SYSCALL
  1997. bool "Enable the LDT (local descriptor table)" if EXPERT
  1998. default y
  1999. ---help---
  2000. Linux can allow user programs to install a per-process x86
  2001. Local Descriptor Table (LDT) using the modify_ldt(2) system
  2002. call. This is required to run 16-bit or segmented code such as
  2003. DOSEMU or some Wine programs. It is also used by some very old
  2004. threading libraries.
  2005. Enabling this feature adds a small amount of overhead to
  2006. context switches and increases the low-level kernel attack
  2007. surface. Disabling it removes the modify_ldt(2) system call.
  2008. Saying 'N' here may make sense for embedded or server kernels.
  2009. source "kernel/livepatch/Kconfig"
  2010. endmenu
  2011. config ARCH_HAS_ADD_PAGES
  2012. def_bool y
  2013. depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
  2014. config ARCH_ENABLE_MEMORY_HOTPLUG
  2015. def_bool y
  2016. depends on X86_64 || (X86_32 && HIGHMEM)
  2017. config ARCH_ENABLE_MEMORY_HOTREMOVE
  2018. def_bool y
  2019. depends on MEMORY_HOTPLUG
  2020. config USE_PERCPU_NUMA_NODE_ID
  2021. def_bool y
  2022. depends on NUMA
  2023. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  2024. def_bool y
  2025. depends on X86_64 || X86_PAE
  2026. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  2027. def_bool y
  2028. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  2029. config ARCH_ENABLE_THP_MIGRATION
  2030. def_bool y
  2031. depends on X86_64 && TRANSPARENT_HUGEPAGE
  2032. menu "Power management and ACPI options"
  2033. config ARCH_HIBERNATION_HEADER
  2034. def_bool y
  2035. depends on X86_64 && HIBERNATION
  2036. source "kernel/power/Kconfig"
  2037. source "drivers/acpi/Kconfig"
  2038. source "drivers/sfi/Kconfig"
  2039. config X86_APM_BOOT
  2040. def_bool y
  2041. depends on APM
  2042. menuconfig APM
  2043. tristate "APM (Advanced Power Management) BIOS support"
  2044. depends on X86_32 && PM_SLEEP
  2045. ---help---
  2046. APM is a BIOS specification for saving power using several different
  2047. techniques. This is mostly useful for battery powered laptops with
  2048. APM compliant BIOSes. If you say Y here, the system time will be
  2049. reset after a RESUME operation, the /proc/apm device will provide
  2050. battery status information, and user-space programs will receive
  2051. notification of APM "events" (e.g. battery status change).
  2052. If you select "Y" here, you can disable actual use of the APM
  2053. BIOS by passing the "apm=off" option to the kernel at boot time.
  2054. Note that the APM support is almost completely disabled for
  2055. machines with more than one CPU.
  2056. In order to use APM, you will need supporting software. For location
  2057. and more information, read <file:Documentation/power/apm-acpi.txt>
  2058. and the Battery Powered Linux mini-HOWTO, available from
  2059. <http://www.tldp.org/docs.html#howto>.
  2060. This driver does not spin down disk drives (see the hdparm(8)
  2061. manpage ("man 8 hdparm") for that), and it doesn't turn off
  2062. VESA-compliant "green" monitors.
  2063. This driver does not support the TI 4000M TravelMate and the ACER
  2064. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  2065. desktop machines also don't have compliant BIOSes, and this driver
  2066. may cause those machines to panic during the boot phase.
  2067. Generally, if you don't have a battery in your machine, there isn't
  2068. much point in using this driver and you should say N. If you get
  2069. random kernel OOPSes or reboots that don't seem to be related to
  2070. anything, try disabling/enabling this option (or disabling/enabling
  2071. APM in your BIOS).
  2072. Some other things you should try when experiencing seemingly random,
  2073. "weird" problems:
  2074. 1) make sure that you have enough swap space and that it is
  2075. enabled.
  2076. 2) pass the "no-hlt" option to the kernel
  2077. 3) switch on floating point emulation in the kernel and pass
  2078. the "no387" option to the kernel
  2079. 4) pass the "floppy=nodma" option to the kernel
  2080. 5) pass the "mem=4M" option to the kernel (thereby disabling
  2081. all but the first 4 MB of RAM)
  2082. 6) make sure that the CPU is not over clocked.
  2083. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  2084. 8) disable the cache from your BIOS settings
  2085. 9) install a fan for the video card or exchange video RAM
  2086. 10) install a better fan for the CPU
  2087. 11) exchange RAM chips
  2088. 12) exchange the motherboard.
  2089. To compile this driver as a module, choose M here: the
  2090. module will be called apm.
  2091. if APM
  2092. config APM_IGNORE_USER_SUSPEND
  2093. bool "Ignore USER SUSPEND"
  2094. ---help---
  2095. This option will ignore USER SUSPEND requests. On machines with a
  2096. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  2097. series notebooks, it is necessary to say Y because of a BIOS bug.
  2098. config APM_DO_ENABLE
  2099. bool "Enable PM at boot time"
  2100. ---help---
  2101. Enable APM features at boot time. From page 36 of the APM BIOS
  2102. specification: "When disabled, the APM BIOS does not automatically
  2103. power manage devices, enter the Standby State, enter the Suspend
  2104. State, or take power saving steps in response to CPU Idle calls."
  2105. This driver will make CPU Idle calls when Linux is idle (unless this
  2106. feature is turned off -- see "Do CPU IDLE calls", below). This
  2107. should always save battery power, but more complicated APM features
  2108. will be dependent on your BIOS implementation. You may need to turn
  2109. this option off if your computer hangs at boot time when using APM
  2110. support, or if it beeps continuously instead of suspending. Turn
  2111. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  2112. T400CDT. This is off by default since most machines do fine without
  2113. this feature.
  2114. config APM_CPU_IDLE
  2115. depends on CPU_IDLE
  2116. bool "Make CPU Idle calls when idle"
  2117. ---help---
  2118. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  2119. On some machines, this can activate improved power savings, such as
  2120. a slowed CPU clock rate, when the machine is idle. These idle calls
  2121. are made after the idle loop has run for some length of time (e.g.,
  2122. 333 mS). On some machines, this will cause a hang at boot time or
  2123. whenever the CPU becomes idle. (On machines with more than one CPU,
  2124. this option does nothing.)
  2125. config APM_DISPLAY_BLANK
  2126. bool "Enable console blanking using APM"
  2127. ---help---
  2128. Enable console blanking using the APM. Some laptops can use this to
  2129. turn off the LCD backlight when the screen blanker of the Linux
  2130. virtual console blanks the screen. Note that this is only used by
  2131. the virtual console screen blanker, and won't turn off the backlight
  2132. when using the X Window system. This also doesn't have anything to
  2133. do with your VESA-compliant power-saving monitor. Further, this
  2134. option doesn't work for all laptops -- it might not turn off your
  2135. backlight at all, or it might print a lot of errors to the console,
  2136. especially if you are using gpm.
  2137. config APM_ALLOW_INTS
  2138. bool "Allow interrupts during APM BIOS calls"
  2139. ---help---
  2140. Normally we disable external interrupts while we are making calls to
  2141. the APM BIOS as a measure to lessen the effects of a badly behaving
  2142. BIOS implementation. The BIOS should reenable interrupts if it
  2143. needs to. Unfortunately, some BIOSes do not -- especially those in
  2144. many of the newer IBM Thinkpads. If you experience hangs when you
  2145. suspend, try setting this to Y. Otherwise, say N.
  2146. endif # APM
  2147. source "drivers/cpufreq/Kconfig"
  2148. source "drivers/cpuidle/Kconfig"
  2149. source "drivers/idle/Kconfig"
  2150. endmenu
  2151. menu "Bus options (PCI etc.)"
  2152. config PCI
  2153. bool "PCI support"
  2154. default y
  2155. ---help---
  2156. Find out whether you have a PCI motherboard. PCI is the name of a
  2157. bus system, i.e. the way the CPU talks to the other stuff inside
  2158. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  2159. VESA. If you have PCI, say Y, otherwise N.
  2160. choice
  2161. prompt "PCI access mode"
  2162. depends on X86_32 && PCI
  2163. default PCI_GOANY
  2164. ---help---
  2165. On PCI systems, the BIOS can be used to detect the PCI devices and
  2166. determine their configuration. However, some old PCI motherboards
  2167. have BIOS bugs and may crash if this is done. Also, some embedded
  2168. PCI-based systems don't have any BIOS at all. Linux can also try to
  2169. detect the PCI hardware directly without using the BIOS.
  2170. With this option, you can specify how Linux should detect the
  2171. PCI devices. If you choose "BIOS", the BIOS will be used,
  2172. if you choose "Direct", the BIOS won't be used, and if you
  2173. choose "MMConfig", then PCI Express MMCONFIG will be used.
  2174. If you choose "Any", the kernel will try MMCONFIG, then the
  2175. direct access method and falls back to the BIOS if that doesn't
  2176. work. If unsure, go with the default, which is "Any".
  2177. config PCI_GOBIOS
  2178. bool "BIOS"
  2179. config PCI_GOMMCONFIG
  2180. bool "MMConfig"
  2181. config PCI_GODIRECT
  2182. bool "Direct"
  2183. config PCI_GOOLPC
  2184. bool "OLPC XO-1"
  2185. depends on OLPC
  2186. config PCI_GOANY
  2187. bool "Any"
  2188. endchoice
  2189. config PCI_BIOS
  2190. def_bool y
  2191. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  2192. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  2193. config PCI_DIRECT
  2194. def_bool y
  2195. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  2196. config PCI_MMCONFIG
  2197. bool "Support mmconfig PCI config space access" if X86_64
  2198. default y
  2199. depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
  2200. depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
  2201. config PCI_OLPC
  2202. def_bool y
  2203. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  2204. config PCI_XEN
  2205. def_bool y
  2206. depends on PCI && XEN
  2207. select SWIOTLB_XEN
  2208. config PCI_DOMAINS
  2209. def_bool y
  2210. depends on PCI
  2211. config MMCONF_FAM10H
  2212. def_bool y
  2213. depends on X86_64 && PCI_MMCONFIG && ACPI
  2214. config PCI_CNB20LE_QUIRK
  2215. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  2216. depends on PCI
  2217. help
  2218. Read the PCI windows out of the CNB20LE host bridge. This allows
  2219. PCI hotplug to work on systems with the CNB20LE chipset which do
  2220. not have ACPI.
  2221. There's no public spec for this chipset, and this functionality
  2222. is known to be incomplete.
  2223. You should say N unless you know you need this.
  2224. source "drivers/pci/Kconfig"
  2225. config ISA_BUS
  2226. bool "ISA bus support on modern systems" if EXPERT
  2227. help
  2228. Expose ISA bus device drivers and options available for selection and
  2229. configuration. Enable this option if your target machine has an ISA
  2230. bus. ISA is an older system, displaced by PCI and newer bus
  2231. architectures -- if your target machine is modern, it probably does
  2232. not have an ISA bus.
  2233. If unsure, say N.
  2234. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2235. config ISA_DMA_API
  2236. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2237. default y
  2238. help
  2239. Enables ISA-style DMA support for devices requiring such controllers.
  2240. If unsure, say Y.
  2241. if X86_32
  2242. config ISA
  2243. bool "ISA support"
  2244. ---help---
  2245. Find out whether you have ISA slots on your motherboard. ISA is the
  2246. name of a bus system, i.e. the way the CPU talks to the other stuff
  2247. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2248. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2249. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2250. config EISA
  2251. bool "EISA support"
  2252. depends on ISA
  2253. ---help---
  2254. The Extended Industry Standard Architecture (EISA) bus was
  2255. developed as an open alternative to the IBM MicroChannel bus.
  2256. The EISA bus provided some of the features of the IBM MicroChannel
  2257. bus while maintaining backward compatibility with cards made for
  2258. the older ISA bus. The EISA bus saw limited use between 1988 and
  2259. 1995 when it was made obsolete by the PCI bus.
  2260. Say Y here if you are building a kernel for an EISA-based machine.
  2261. Otherwise, say N.
  2262. source "drivers/eisa/Kconfig"
  2263. config SCx200
  2264. tristate "NatSemi SCx200 support"
  2265. ---help---
  2266. This provides basic support for National Semiconductor's
  2267. (now AMD's) Geode processors. The driver probes for the
  2268. PCI-IDs of several on-chip devices, so its a good dependency
  2269. for other scx200_* drivers.
  2270. If compiled as a module, the driver is named scx200.
  2271. config SCx200HR_TIMER
  2272. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2273. depends on SCx200
  2274. default y
  2275. ---help---
  2276. This driver provides a clocksource built upon the on-chip
  2277. 27MHz high-resolution timer. Its also a workaround for
  2278. NSC Geode SC-1100's buggy TSC, which loses time when the
  2279. processor goes idle (as is done by the scheduler). The
  2280. other workaround is idle=poll boot option.
  2281. config OLPC
  2282. bool "One Laptop Per Child support"
  2283. depends on !X86_PAE
  2284. select GPIOLIB
  2285. select OF
  2286. select OF_PROMTREE
  2287. select IRQ_DOMAIN
  2288. ---help---
  2289. Add support for detecting the unique features of the OLPC
  2290. XO hardware.
  2291. config OLPC_XO1_PM
  2292. bool "OLPC XO-1 Power Management"
  2293. depends on OLPC && MFD_CS5535 && PM_SLEEP
  2294. select MFD_CORE
  2295. ---help---
  2296. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2297. config OLPC_XO1_RTC
  2298. bool "OLPC XO-1 Real Time Clock"
  2299. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2300. ---help---
  2301. Add support for the XO-1 real time clock, which can be used as a
  2302. programmable wakeup source.
  2303. config OLPC_XO1_SCI
  2304. bool "OLPC XO-1 SCI extras"
  2305. depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
  2306. depends on INPUT=y
  2307. select POWER_SUPPLY
  2308. ---help---
  2309. Add support for SCI-based features of the OLPC XO-1 laptop:
  2310. - EC-driven system wakeups
  2311. - Power button
  2312. - Ebook switch
  2313. - Lid switch
  2314. - AC adapter status updates
  2315. - Battery status updates
  2316. config OLPC_XO15_SCI
  2317. bool "OLPC XO-1.5 SCI extras"
  2318. depends on OLPC && ACPI
  2319. select POWER_SUPPLY
  2320. ---help---
  2321. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2322. - EC-driven system wakeups
  2323. - AC adapter status updates
  2324. - Battery status updates
  2325. config ALIX
  2326. bool "PCEngines ALIX System Support (LED setup)"
  2327. select GPIOLIB
  2328. ---help---
  2329. This option enables system support for the PCEngines ALIX.
  2330. At present this just sets up LEDs for GPIO control on
  2331. ALIX2/3/6 boards. However, other system specific setup should
  2332. get added here.
  2333. Note: You must still enable the drivers for GPIO and LED support
  2334. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2335. Note: You have to set alix.force=1 for boards with Award BIOS.
  2336. config NET5501
  2337. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2338. select GPIOLIB
  2339. ---help---
  2340. This option enables system support for the Soekris Engineering net5501.
  2341. config GEOS
  2342. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2343. select GPIOLIB
  2344. depends on DMI
  2345. ---help---
  2346. This option enables system support for the Traverse Technologies GEOS.
  2347. config TS5500
  2348. bool "Technologic Systems TS-5500 platform support"
  2349. depends on MELAN
  2350. select CHECK_SIGNATURE
  2351. select NEW_LEDS
  2352. select LEDS_CLASS
  2353. ---help---
  2354. This option enables system support for the Technologic Systems TS-5500.
  2355. endif # X86_32
  2356. config AMD_NB
  2357. def_bool y
  2358. depends on CPU_SUP_AMD && PCI
  2359. source "drivers/pcmcia/Kconfig"
  2360. config RAPIDIO
  2361. tristate "RapidIO support"
  2362. depends on PCI
  2363. default n
  2364. help
  2365. If enabled this option will include drivers and the core
  2366. infrastructure code to support RapidIO interconnect devices.
  2367. source "drivers/rapidio/Kconfig"
  2368. config X86_SYSFB
  2369. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2370. help
  2371. Firmwares often provide initial graphics framebuffers so the BIOS,
  2372. bootloader or kernel can show basic video-output during boot for
  2373. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2374. Extensions and EFI-framebuffers for this, which are mostly limited
  2375. to x86.
  2376. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2377. framebuffers so the new generic system-framebuffer drivers can be
  2378. used on x86. If the framebuffer is not compatible with the generic
  2379. modes, it is adverticed as fallback platform framebuffer so legacy
  2380. drivers like efifb, vesafb and uvesafb can pick it up.
  2381. If this option is not selected, all system framebuffers are always
  2382. marked as fallback platform framebuffers as usual.
  2383. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2384. not be able to pick up generic system framebuffers if this option
  2385. is selected. You are highly encouraged to enable simplefb as
  2386. replacement if you select this option. simplefb can correctly deal
  2387. with generic system framebuffers. But you should still keep vesafb
  2388. and others enabled as fallback if a system framebuffer is
  2389. incompatible with simplefb.
  2390. If unsure, say Y.
  2391. endmenu
  2392. menu "Executable file formats / Emulations"
  2393. source "fs/Kconfig.binfmt"
  2394. config IA32_EMULATION
  2395. bool "IA32 Emulation"
  2396. depends on X86_64
  2397. select ARCH_WANT_OLD_COMPAT_IPC
  2398. select BINFMT_ELF
  2399. select COMPAT_BINFMT_ELF
  2400. select COMPAT_OLD_SIGACTION
  2401. ---help---
  2402. Include code to run legacy 32-bit programs under a
  2403. 64-bit kernel. You should likely turn this on, unless you're
  2404. 100% sure that you don't have any 32-bit programs left.
  2405. config IA32_AOUT
  2406. tristate "IA32 a.out support"
  2407. depends on IA32_EMULATION
  2408. ---help---
  2409. Support old a.out binaries in the 32bit emulation.
  2410. config X86_X32
  2411. bool "x32 ABI for 64-bit mode"
  2412. depends on X86_64
  2413. ---help---
  2414. Include code to run binaries for the x32 native 32-bit ABI
  2415. for 64-bit processors. An x32 process gets access to the
  2416. full 64-bit register file and wide data path while leaving
  2417. pointers at 32 bits for smaller memory footprint.
  2418. You will need a recent binutils (2.22 or later) with
  2419. elf32_x86_64 support enabled to compile a kernel with this
  2420. option set.
  2421. config COMPAT_32
  2422. def_bool y
  2423. depends on IA32_EMULATION || X86_32
  2424. select HAVE_UID16
  2425. select OLD_SIGSUSPEND3
  2426. config COMPAT
  2427. def_bool y
  2428. depends on IA32_EMULATION || X86_X32
  2429. if COMPAT
  2430. config COMPAT_FOR_U64_ALIGNMENT
  2431. def_bool y
  2432. config SYSVIPC_COMPAT
  2433. def_bool y
  2434. depends on SYSVIPC
  2435. endif
  2436. endmenu
  2437. config HAVE_ATOMIC_IOMAP
  2438. def_bool y
  2439. depends on X86_32
  2440. config X86_DEV_DMA_OPS
  2441. bool
  2442. depends on X86_64 || STA2X11
  2443. config X86_DMA_REMAP
  2444. bool
  2445. depends on STA2X11
  2446. config HAVE_GENERIC_GUP
  2447. def_bool y
  2448. source "net/Kconfig"
  2449. source "drivers/Kconfig"
  2450. source "drivers/firmware/Kconfig"
  2451. source "fs/Kconfig"
  2452. source "arch/x86/Kconfig.debug"
  2453. source "security/Kconfig"
  2454. source "crypto/Kconfig"
  2455. source "arch/x86/kvm/Kconfig"
  2456. source "lib/Kconfig"