Kconfig 95 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_CLOCKSOURCE_INIT
  49. select ARCH_DISCARD_MEMBLOCK
  50. select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
  51. select ARCH_HAS_DEBUG_VIRTUAL
  52. select ARCH_HAS_DEVMEM_IS_ALLOWED
  53. select ARCH_HAS_ELF_RANDOMIZE
  54. select ARCH_HAS_FAST_MULTIPLIER
  55. select ARCH_HAS_FILTER_PGPROT
  56. select ARCH_HAS_FORTIFY_SOURCE
  57. select ARCH_HAS_GCOV_PROFILE_ALL
  58. select ARCH_HAS_KCOV if X86_64
  59. select ARCH_HAS_MEMBARRIER_SYNC_CORE
  60. select ARCH_HAS_PMEM_API if X86_64
  61. select ARCH_HAS_PTE_SPECIAL
  62. select ARCH_HAS_REFCOUNT
  63. select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
  64. select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
  65. select ARCH_HAS_SET_MEMORY
  66. select ARCH_HAS_SG_CHAIN
  67. select ARCH_HAS_STRICT_KERNEL_RWX
  68. select ARCH_HAS_STRICT_MODULE_RWX
  69. select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
  70. select ARCH_HAS_UBSAN_SANITIZE_ALL
  71. select ARCH_HAS_ZONE_DEVICE if X86_64
  72. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  73. select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  74. select ARCH_MIGHT_HAVE_PC_PARPORT
  75. select ARCH_MIGHT_HAVE_PC_SERIO
  76. select ARCH_SUPPORTS_ACPI
  77. select ARCH_SUPPORTS_ATOMIC_RMW
  78. select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
  79. select ARCH_USE_BUILTIN_BSWAP
  80. select ARCH_USE_QUEUED_RWLOCKS
  81. select ARCH_USE_QUEUED_SPINLOCKS
  82. select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
  83. select ARCH_WANTS_DYNAMIC_TASK_STRUCT
  84. select ARCH_WANTS_THP_SWAP if X86_64
  85. select BUILDTIME_EXTABLE_SORT
  86. select CLKEVT_I8253
  87. select CLOCKSOURCE_VALIDATE_LAST_CYCLE
  88. select CLOCKSOURCE_WATCHDOG
  89. select DCACHE_WORD_ACCESS
  90. select DMA_DIRECT_OPS
  91. select EDAC_ATOMIC_SCRUB
  92. select EDAC_SUPPORT
  93. select GENERIC_CLOCKEVENTS
  94. select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
  95. select GENERIC_CLOCKEVENTS_MIN_ADJUST
  96. select GENERIC_CMOS_UPDATE
  97. select GENERIC_CPU_AUTOPROBE
  98. select GENERIC_CPU_VULNERABILITIES
  99. select GENERIC_EARLY_IOREMAP
  100. select GENERIC_FIND_FIRST_BIT
  101. select GENERIC_IOMAP
  102. select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
  103. select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
  104. select GENERIC_IRQ_MIGRATION if SMP
  105. select GENERIC_IRQ_PROBE
  106. select GENERIC_IRQ_RESERVATION_MODE
  107. select GENERIC_IRQ_SHOW
  108. select GENERIC_PENDING_IRQ if SMP
  109. select GENERIC_SMP_IDLE_THREAD
  110. select GENERIC_STRNCPY_FROM_USER
  111. select GENERIC_STRNLEN_USER
  112. select GENERIC_TIME_VSYSCALL
  113. select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
  114. select HAVE_ACPI_APEI if ACPI
  115. select HAVE_ACPI_APEI_NMI if ACPI
  116. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  117. select HAVE_ARCH_AUDITSYSCALL
  118. select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
  119. select HAVE_ARCH_JUMP_LABEL
  120. select HAVE_ARCH_JUMP_LABEL_RELATIVE
  121. select HAVE_ARCH_KASAN if X86_64
  122. select HAVE_ARCH_KGDB
  123. select HAVE_ARCH_MMAP_RND_BITS if MMU
  124. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
  125. select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
  126. select HAVE_ARCH_PREL32_RELOCATIONS
  127. select HAVE_ARCH_SECCOMP_FILTER
  128. select HAVE_ARCH_THREAD_STRUCT_WHITELIST
  129. select HAVE_ARCH_STACKLEAK
  130. select HAVE_ARCH_TRACEHOOK
  131. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  132. select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
  133. select HAVE_ARCH_VMAP_STACK if X86_64
  134. select HAVE_ARCH_WITHIN_STACK_FRAMES
  135. select HAVE_CMPXCHG_DOUBLE
  136. select HAVE_CMPXCHG_LOCAL
  137. select HAVE_CONTEXT_TRACKING if X86_64
  138. select HAVE_COPY_THREAD_TLS
  139. select HAVE_C_RECORDMCOUNT
  140. select HAVE_DEBUG_KMEMLEAK
  141. select HAVE_DEBUG_STACKOVERFLOW
  142. select HAVE_DMA_CONTIGUOUS
  143. select HAVE_DYNAMIC_FTRACE
  144. select HAVE_DYNAMIC_FTRACE_WITH_REGS
  145. select HAVE_EBPF_JIT
  146. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  147. select HAVE_EXIT_THREAD
  148. select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
  149. select HAVE_FTRACE_MCOUNT_RECORD
  150. select HAVE_FUNCTION_GRAPH_TRACER
  151. select HAVE_FUNCTION_TRACER
  152. select HAVE_GCC_PLUGINS
  153. select HAVE_HW_BREAKPOINT
  154. select HAVE_IDE
  155. select HAVE_IOREMAP_PROT
  156. select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
  157. select HAVE_IRQ_TIME_ACCOUNTING
  158. select HAVE_KERNEL_BZIP2
  159. select HAVE_KERNEL_GZIP
  160. select HAVE_KERNEL_LZ4
  161. select HAVE_KERNEL_LZMA
  162. select HAVE_KERNEL_LZO
  163. select HAVE_KERNEL_XZ
  164. select HAVE_KPROBES
  165. select HAVE_KPROBES_ON_FTRACE
  166. select HAVE_FUNCTION_ERROR_INJECTION
  167. select HAVE_KRETPROBES
  168. select HAVE_KVM
  169. select HAVE_LIVEPATCH if X86_64
  170. select HAVE_MEMBLOCK_NODE_MAP
  171. select HAVE_MIXED_BREAKPOINTS_REGS
  172. select HAVE_MOD_ARCH_SPECIFIC
  173. select HAVE_NMI
  174. select HAVE_OPROFILE
  175. select HAVE_OPTPROBES
  176. select HAVE_PCSPKR_PLATFORM
  177. select HAVE_PERF_EVENTS
  178. select HAVE_PERF_EVENTS_NMI
  179. select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
  180. select HAVE_PERF_REGS
  181. select HAVE_PERF_USER_STACK_DUMP
  182. select HAVE_RCU_TABLE_FREE if PARAVIRT
  183. select HAVE_RCU_TABLE_INVALIDATE if HAVE_RCU_TABLE_FREE
  184. select HAVE_REGS_AND_STACK_ACCESS_API
  185. select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
  186. select HAVE_FUNCTION_ARG_ACCESS_API
  187. select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
  188. select HAVE_STACK_VALIDATION if X86_64
  189. select HAVE_RSEQ
  190. select HAVE_SYSCALL_TRACEPOINTS
  191. select HAVE_UNSTABLE_SCHED_CLOCK
  192. select HAVE_USER_RETURN_NOTIFIER
  193. select HOTPLUG_SMT if SMP
  194. select IRQ_FORCED_THREADING
  195. select NEED_SG_DMA_LENGTH
  196. select PCI_LOCKLESS_CONFIG
  197. select PERF_EVENTS
  198. select RTC_LIB
  199. select RTC_MC146818_LIB
  200. select SPARSE_IRQ
  201. select SRCU
  202. select SYSCTL_EXCEPTION_TRACE
  203. select THREAD_INFO_IN_TASK
  204. select USER_STACKTRACE_SUPPORT
  205. select VIRT_TO_BUS
  206. select X86_FEATURE_NAMES if PROC_FS
  207. config INSTRUCTION_DECODER
  208. def_bool y
  209. depends on KPROBES || PERF_EVENTS || UPROBES
  210. config OUTPUT_FORMAT
  211. string
  212. default "elf32-i386" if X86_32
  213. default "elf64-x86-64" if X86_64
  214. config ARCH_DEFCONFIG
  215. string
  216. default "arch/x86/configs/i386_defconfig" if X86_32
  217. default "arch/x86/configs/x86_64_defconfig" if X86_64
  218. config LOCKDEP_SUPPORT
  219. def_bool y
  220. config STACKTRACE_SUPPORT
  221. def_bool y
  222. config MMU
  223. def_bool y
  224. config ARCH_MMAP_RND_BITS_MIN
  225. default 28 if 64BIT
  226. default 8
  227. config ARCH_MMAP_RND_BITS_MAX
  228. default 32 if 64BIT
  229. default 16
  230. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  231. default 8
  232. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  233. default 16
  234. config SBUS
  235. bool
  236. config GENERIC_ISA_DMA
  237. def_bool y
  238. depends on ISA_DMA_API
  239. config GENERIC_BUG
  240. def_bool y
  241. depends on BUG
  242. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  243. config GENERIC_BUG_RELATIVE_POINTERS
  244. bool
  245. config GENERIC_HWEIGHT
  246. def_bool y
  247. config ARCH_MAY_HAVE_PC_FDC
  248. def_bool y
  249. depends on ISA_DMA_API
  250. config RWSEM_XCHGADD_ALGORITHM
  251. def_bool y
  252. config GENERIC_CALIBRATE_DELAY
  253. def_bool y
  254. config ARCH_HAS_CPU_RELAX
  255. def_bool y
  256. config ARCH_HAS_CACHE_LINE_SIZE
  257. def_bool y
  258. config ARCH_HAS_FILTER_PGPROT
  259. def_bool y
  260. config HAVE_SETUP_PER_CPU_AREA
  261. def_bool y
  262. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  263. def_bool y
  264. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  265. def_bool y
  266. config ARCH_HIBERNATION_POSSIBLE
  267. def_bool y
  268. config ARCH_SUSPEND_POSSIBLE
  269. def_bool y
  270. config ARCH_WANT_HUGE_PMD_SHARE
  271. def_bool y
  272. config ARCH_WANT_GENERAL_HUGETLB
  273. def_bool y
  274. config ZONE_DMA32
  275. def_bool y if X86_64
  276. config AUDIT_ARCH
  277. def_bool y if X86_64
  278. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  279. def_bool y
  280. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  281. def_bool y
  282. config KASAN_SHADOW_OFFSET
  283. hex
  284. depends on KASAN
  285. default 0xdffffc0000000000
  286. config HAVE_INTEL_TXT
  287. def_bool y
  288. depends on INTEL_IOMMU && ACPI
  289. config X86_32_SMP
  290. def_bool y
  291. depends on X86_32 && SMP
  292. config X86_64_SMP
  293. def_bool y
  294. depends on X86_64 && SMP
  295. config X86_32_LAZY_GS
  296. def_bool y
  297. depends on X86_32 && !STACKPROTECTOR
  298. config ARCH_SUPPORTS_UPROBES
  299. def_bool y
  300. config FIX_EARLYCON_MEM
  301. def_bool y
  302. config DYNAMIC_PHYSICAL_MASK
  303. bool
  304. config PGTABLE_LEVELS
  305. int
  306. default 5 if X86_5LEVEL
  307. default 4 if X86_64
  308. default 3 if X86_PAE
  309. default 2
  310. config CC_HAS_SANE_STACKPROTECTOR
  311. bool
  312. default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
  313. default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
  314. help
  315. We have to make sure stack protector is unconditionally disabled if
  316. the compiler produces broken code.
  317. menu "Processor type and features"
  318. config ZONE_DMA
  319. bool "DMA memory allocation support" if EXPERT
  320. default y
  321. help
  322. DMA memory allocation support allows devices with less than 32-bit
  323. addressing to allocate within the first 16MB of address space.
  324. Disable if no such devices will be used.
  325. If unsure, say Y.
  326. config SMP
  327. bool "Symmetric multi-processing support"
  328. ---help---
  329. This enables support for systems with more than one CPU. If you have
  330. a system with only one CPU, say N. If you have a system with more
  331. than one CPU, say Y.
  332. If you say N here, the kernel will run on uni- and multiprocessor
  333. machines, but will use only one CPU of a multiprocessor machine. If
  334. you say Y here, the kernel will run on many, but not all,
  335. uniprocessor machines. On a uniprocessor machine, the kernel
  336. will run faster if you say N here.
  337. Note that if you say Y here and choose architecture "586" or
  338. "Pentium" under "Processor family", the kernel will not work on 486
  339. architectures. Similarly, multiprocessor kernels for the "PPro"
  340. architecture may not work on all Pentium based boards.
  341. People using multiprocessor machines who say Y here should also say
  342. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  343. Management" code will be disabled if you say Y here.
  344. See also <file:Documentation/x86/i386/IO-APIC.txt>,
  345. <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
  346. <http://www.tldp.org/docs.html#howto>.
  347. If you don't know what to do here, say N.
  348. config X86_FEATURE_NAMES
  349. bool "Processor feature human-readable names" if EMBEDDED
  350. default y
  351. ---help---
  352. This option compiles in a table of x86 feature bits and corresponding
  353. names. This is required to support /proc/cpuinfo and a few kernel
  354. messages. You can disable this to save space, at the expense of
  355. making those few kernel messages show numeric feature bits instead.
  356. If in doubt, say Y.
  357. config X86_X2APIC
  358. bool "Support x2apic"
  359. depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
  360. ---help---
  361. This enables x2apic support on CPUs that have this feature.
  362. This allows 32-bit apic IDs (so it can support very large systems),
  363. and accesses the local apic via MSRs not via mmio.
  364. If you don't know what to do here, say N.
  365. config X86_MPPARSE
  366. bool "Enable MPS table" if ACPI || SFI
  367. default y
  368. depends on X86_LOCAL_APIC
  369. ---help---
  370. For old smp systems that do not have proper acpi support. Newer systems
  371. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  372. config GOLDFISH
  373. def_bool y
  374. depends on X86_GOLDFISH
  375. config RETPOLINE
  376. bool "Avoid speculative indirect branches in kernel"
  377. default y
  378. select STACK_VALIDATION if HAVE_STACK_VALIDATION
  379. help
  380. Compile kernel with the retpoline compiler options to guard against
  381. kernel-to-user data leaks by avoiding speculative indirect
  382. branches. Requires a compiler with -mindirect-branch=thunk-extern
  383. support for full protection. The kernel may run slower.
  384. config INTEL_RDT
  385. bool "Intel Resource Director Technology support"
  386. depends on X86 && CPU_SUP_INTEL
  387. select KERNFS
  388. help
  389. Select to enable resource allocation and monitoring which are
  390. sub-features of Intel Resource Director Technology(RDT). More
  391. information about RDT can be found in the Intel x86
  392. Architecture Software Developer Manual.
  393. Say N if unsure.
  394. if X86_32
  395. config X86_BIGSMP
  396. bool "Support for big SMP systems with more than 8 CPUs"
  397. depends on SMP
  398. ---help---
  399. This option is needed for the systems that have more than 8 CPUs
  400. config X86_EXTENDED_PLATFORM
  401. bool "Support for extended (non-PC) x86 platforms"
  402. default y
  403. ---help---
  404. If you disable this option then the kernel will only support
  405. standard PC platforms. (which covers the vast majority of
  406. systems out there.)
  407. If you enable this option then you'll be able to select support
  408. for the following (non-PC) 32 bit x86 platforms:
  409. Goldfish (Android emulator)
  410. AMD Elan
  411. RDC R-321x SoC
  412. SGI 320/540 (Visual Workstation)
  413. STA2X11-based (e.g. Northville)
  414. Moorestown MID devices
  415. If you have one of these systems, or if you want to build a
  416. generic distribution kernel, say Y here - otherwise say N.
  417. endif
  418. if X86_64
  419. config X86_EXTENDED_PLATFORM
  420. bool "Support for extended (non-PC) x86 platforms"
  421. default y
  422. ---help---
  423. If you disable this option then the kernel will only support
  424. standard PC platforms. (which covers the vast majority of
  425. systems out there.)
  426. If you enable this option then you'll be able to select support
  427. for the following (non-PC) 64 bit x86 platforms:
  428. Numascale NumaChip
  429. ScaleMP vSMP
  430. SGI Ultraviolet
  431. If you have one of these systems, or if you want to build a
  432. generic distribution kernel, say Y here - otherwise say N.
  433. endif
  434. # This is an alphabetically sorted list of 64 bit extended platforms
  435. # Please maintain the alphabetic order if and when there are additions
  436. config X86_NUMACHIP
  437. bool "Numascale NumaChip"
  438. depends on X86_64
  439. depends on X86_EXTENDED_PLATFORM
  440. depends on NUMA
  441. depends on SMP
  442. depends on X86_X2APIC
  443. depends on PCI_MMCONFIG
  444. ---help---
  445. Adds support for Numascale NumaChip large-SMP systems. Needed to
  446. enable more than ~168 cores.
  447. If you don't have one of these, you should say N here.
  448. config X86_VSMP
  449. bool "ScaleMP vSMP"
  450. select HYPERVISOR_GUEST
  451. select PARAVIRT
  452. depends on X86_64 && PCI
  453. depends on X86_EXTENDED_PLATFORM
  454. depends on SMP
  455. ---help---
  456. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  457. supposed to run on these EM64T-based machines. Only choose this option
  458. if you have one of these machines.
  459. config X86_UV
  460. bool "SGI Ultraviolet"
  461. depends on X86_64
  462. depends on X86_EXTENDED_PLATFORM
  463. depends on NUMA
  464. depends on EFI
  465. depends on X86_X2APIC
  466. depends on PCI
  467. ---help---
  468. This option is needed in order to support SGI Ultraviolet systems.
  469. If you don't have one of these, you should say N here.
  470. # Following is an alphabetically sorted list of 32 bit extended platforms
  471. # Please maintain the alphabetic order if and when there are additions
  472. config X86_GOLDFISH
  473. bool "Goldfish (Virtual Platform)"
  474. depends on X86_EXTENDED_PLATFORM
  475. ---help---
  476. Enable support for the Goldfish virtual platform used primarily
  477. for Android development. Unless you are building for the Android
  478. Goldfish emulator say N here.
  479. config X86_INTEL_CE
  480. bool "CE4100 TV platform"
  481. depends on PCI
  482. depends on PCI_GODIRECT
  483. depends on X86_IO_APIC
  484. depends on X86_32
  485. depends on X86_EXTENDED_PLATFORM
  486. select X86_REBOOTFIXUPS
  487. select OF
  488. select OF_EARLY_FLATTREE
  489. ---help---
  490. Select for the Intel CE media processor (CE4100) SOC.
  491. This option compiles in support for the CE4100 SOC for settop
  492. boxes and media devices.
  493. config X86_INTEL_MID
  494. bool "Intel MID platform support"
  495. depends on X86_EXTENDED_PLATFORM
  496. depends on X86_PLATFORM_DEVICES
  497. depends on PCI
  498. depends on X86_64 || (PCI_GOANY && X86_32)
  499. depends on X86_IO_APIC
  500. select SFI
  501. select I2C
  502. select DW_APB_TIMER
  503. select APB_TIMER
  504. select INTEL_SCU_IPC
  505. select MFD_INTEL_MSIC
  506. ---help---
  507. Select to build a kernel capable of supporting Intel MID (Mobile
  508. Internet Device) platform systems which do not have the PCI legacy
  509. interfaces. If you are building for a PC class system say N here.
  510. Intel MID platforms are based on an Intel processor and chipset which
  511. consume less power than most of the x86 derivatives.
  512. config X86_INTEL_QUARK
  513. bool "Intel Quark platform support"
  514. depends on X86_32
  515. depends on X86_EXTENDED_PLATFORM
  516. depends on X86_PLATFORM_DEVICES
  517. depends on X86_TSC
  518. depends on PCI
  519. depends on PCI_GOANY
  520. depends on X86_IO_APIC
  521. select IOSF_MBI
  522. select INTEL_IMR
  523. select COMMON_CLK
  524. ---help---
  525. Select to include support for Quark X1000 SoC.
  526. Say Y here if you have a Quark based system such as the Arduino
  527. compatible Intel Galileo.
  528. config X86_INTEL_LPSS
  529. bool "Intel Low Power Subsystem Support"
  530. depends on X86 && ACPI
  531. select COMMON_CLK
  532. select PINCTRL
  533. select IOSF_MBI
  534. ---help---
  535. Select to build support for Intel Low Power Subsystem such as
  536. found on Intel Lynxpoint PCH. Selecting this option enables
  537. things like clock tree (common clock framework) and pincontrol
  538. which are needed by the LPSS peripheral drivers.
  539. config X86_AMD_PLATFORM_DEVICE
  540. bool "AMD ACPI2Platform devices support"
  541. depends on ACPI
  542. select COMMON_CLK
  543. select PINCTRL
  544. ---help---
  545. Select to interpret AMD specific ACPI device to platform device
  546. such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
  547. I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
  548. implemented under PINCTRL subsystem.
  549. config IOSF_MBI
  550. tristate "Intel SoC IOSF Sideband support for SoC platforms"
  551. depends on PCI
  552. ---help---
  553. This option enables sideband register access support for Intel SoC
  554. platforms. On these platforms the IOSF sideband is used in lieu of
  555. MSR's for some register accesses, mostly but not limited to thermal
  556. and power. Drivers may query the availability of this device to
  557. determine if they need the sideband in order to work on these
  558. platforms. The sideband is available on the following SoC products.
  559. This list is not meant to be exclusive.
  560. - BayTrail
  561. - Braswell
  562. - Quark
  563. You should say Y if you are running a kernel on one of these SoC's.
  564. config IOSF_MBI_DEBUG
  565. bool "Enable IOSF sideband access through debugfs"
  566. depends on IOSF_MBI && DEBUG_FS
  567. ---help---
  568. Select this option to expose the IOSF sideband access registers (MCR,
  569. MDR, MCRX) through debugfs to write and read register information from
  570. different units on the SoC. This is most useful for obtaining device
  571. state information for debug and analysis. As this is a general access
  572. mechanism, users of this option would have specific knowledge of the
  573. device they want to access.
  574. If you don't require the option or are in doubt, say N.
  575. config X86_RDC321X
  576. bool "RDC R-321x SoC"
  577. depends on X86_32
  578. depends on X86_EXTENDED_PLATFORM
  579. select M486
  580. select X86_REBOOTFIXUPS
  581. ---help---
  582. This option is needed for RDC R-321x system-on-chip, also known
  583. as R-8610-(G).
  584. If you don't have one of these chips, you should say N here.
  585. config X86_32_NON_STANDARD
  586. bool "Support non-standard 32-bit SMP architectures"
  587. depends on X86_32 && SMP
  588. depends on X86_EXTENDED_PLATFORM
  589. ---help---
  590. This option compiles in the bigsmp and STA2X11 default
  591. subarchitectures. It is intended for a generic binary
  592. kernel. If you select them all, kernel will probe it one by
  593. one and will fallback to default.
  594. # Alphabetically sorted list of Non standard 32 bit platforms
  595. config X86_SUPPORTS_MEMORY_FAILURE
  596. def_bool y
  597. # MCE code calls memory_failure():
  598. depends on X86_MCE
  599. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  600. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  601. depends on X86_64 || !SPARSEMEM
  602. select ARCH_SUPPORTS_MEMORY_FAILURE
  603. config STA2X11
  604. bool "STA2X11 Companion Chip Support"
  605. depends on X86_32_NON_STANDARD && PCI
  606. select ARCH_HAS_PHYS_TO_DMA
  607. select X86_DEV_DMA_OPS
  608. select X86_DMA_REMAP
  609. select SWIOTLB
  610. select MFD_STA2X11
  611. select GPIOLIB
  612. ---help---
  613. This adds support for boards based on the STA2X11 IO-Hub,
  614. a.k.a. "ConneXt". The chip is used in place of the standard
  615. PC chipset, so all "standard" peripherals are missing. If this
  616. option is selected the kernel will still be able to boot on
  617. standard PC machines.
  618. config X86_32_IRIS
  619. tristate "Eurobraille/Iris poweroff module"
  620. depends on X86_32
  621. ---help---
  622. The Iris machines from EuroBraille do not have APM or ACPI support
  623. to shut themselves down properly. A special I/O sequence is
  624. needed to do so, which is what this module does at
  625. kernel shutdown.
  626. This is only for Iris machines from EuroBraille.
  627. If unused, say N.
  628. config SCHED_OMIT_FRAME_POINTER
  629. def_bool y
  630. prompt "Single-depth WCHAN output"
  631. depends on X86
  632. ---help---
  633. Calculate simpler /proc/<PID>/wchan values. If this option
  634. is disabled then wchan values will recurse back to the
  635. caller function. This provides more accurate wchan values,
  636. at the expense of slightly more scheduling overhead.
  637. If in doubt, say "Y".
  638. menuconfig HYPERVISOR_GUEST
  639. bool "Linux guest support"
  640. ---help---
  641. Say Y here to enable options for running Linux under various hyper-
  642. visors. This option enables basic hypervisor detection and platform
  643. setup.
  644. If you say N, all options in this submenu will be skipped and
  645. disabled, and Linux guest support won't be built in.
  646. if HYPERVISOR_GUEST
  647. config PARAVIRT
  648. bool "Enable paravirtualization code"
  649. ---help---
  650. This changes the kernel so it can modify itself when it is run
  651. under a hypervisor, potentially improving performance significantly
  652. over full virtualization. However, when run without a hypervisor
  653. the kernel is theoretically slower and slightly larger.
  654. config PARAVIRT_XXL
  655. bool
  656. config PARAVIRT_DEBUG
  657. bool "paravirt-ops debugging"
  658. depends on PARAVIRT && DEBUG_KERNEL
  659. ---help---
  660. Enable to debug paravirt_ops internals. Specifically, BUG if
  661. a paravirt_op is missing when it is called.
  662. config PARAVIRT_SPINLOCKS
  663. bool "Paravirtualization layer for spinlocks"
  664. depends on PARAVIRT && SMP
  665. ---help---
  666. Paravirtualized spinlocks allow a pvops backend to replace the
  667. spinlock implementation with something virtualization-friendly
  668. (for example, block the virtual CPU rather than spinning).
  669. It has a minimal impact on native kernels and gives a nice performance
  670. benefit on paravirtualized KVM / Xen kernels.
  671. If you are unsure how to answer this question, answer Y.
  672. config QUEUED_LOCK_STAT
  673. bool "Paravirt queued spinlock statistics"
  674. depends on PARAVIRT_SPINLOCKS && DEBUG_FS
  675. ---help---
  676. Enable the collection of statistical data on the slowpath
  677. behavior of paravirtualized queued spinlocks and report
  678. them on debugfs.
  679. source "arch/x86/xen/Kconfig"
  680. config KVM_GUEST
  681. bool "KVM Guest support (including kvmclock)"
  682. depends on PARAVIRT
  683. select PARAVIRT_CLOCK
  684. default y
  685. ---help---
  686. This option enables various optimizations for running under the KVM
  687. hypervisor. It includes a paravirtualized clock, so that instead
  688. of relying on a PIT (or probably other) emulation by the
  689. underlying device model, the host provides the guest with
  690. timing infrastructure such as time of day, and system time
  691. config KVM_DEBUG_FS
  692. bool "Enable debug information for KVM Guests in debugfs"
  693. depends on KVM_GUEST && DEBUG_FS
  694. ---help---
  695. This option enables collection of various statistics for KVM guest.
  696. Statistics are displayed in debugfs filesystem. Enabling this option
  697. may incur significant overhead.
  698. config PARAVIRT_TIME_ACCOUNTING
  699. bool "Paravirtual steal time accounting"
  700. depends on PARAVIRT
  701. ---help---
  702. Select this option to enable fine granularity task steal time
  703. accounting. Time spent executing other tasks in parallel with
  704. the current vCPU is discounted from the vCPU power. To account for
  705. that, there can be a small performance impact.
  706. If in doubt, say N here.
  707. config PARAVIRT_CLOCK
  708. bool
  709. config JAILHOUSE_GUEST
  710. bool "Jailhouse non-root cell support"
  711. depends on X86_64 && PCI
  712. select X86_PM_TIMER
  713. ---help---
  714. This option allows to run Linux as guest in a Jailhouse non-root
  715. cell. You can leave this option disabled if you only want to start
  716. Jailhouse and run Linux afterwards in the root cell.
  717. endif #HYPERVISOR_GUEST
  718. source "arch/x86/Kconfig.cpu"
  719. config HPET_TIMER
  720. def_bool X86_64
  721. prompt "HPET Timer Support" if X86_32
  722. ---help---
  723. Use the IA-PC HPET (High Precision Event Timer) to manage
  724. time in preference to the PIT and RTC, if a HPET is
  725. present.
  726. HPET is the next generation timer replacing legacy 8254s.
  727. The HPET provides a stable time base on SMP
  728. systems, unlike the TSC, but it is more expensive to access,
  729. as it is off-chip. The interface used is documented
  730. in the HPET spec, revision 1.
  731. You can safely choose Y here. However, HPET will only be
  732. activated if the platform and the BIOS support this feature.
  733. Otherwise the 8254 will be used for timing services.
  734. Choose N to continue using the legacy 8254 timer.
  735. config HPET_EMULATE_RTC
  736. def_bool y
  737. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  738. config APB_TIMER
  739. def_bool y if X86_INTEL_MID
  740. prompt "Intel MID APB Timer Support" if X86_INTEL_MID
  741. select DW_APB_TIMER
  742. depends on X86_INTEL_MID && SFI
  743. help
  744. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  745. The APBT provides a stable time base on SMP
  746. systems, unlike the TSC, but it is more expensive to access,
  747. as it is off-chip. APB timers are always running regardless of CPU
  748. C states, they are used as per CPU clockevent device when possible.
  749. # Mark as expert because too many people got it wrong.
  750. # The code disables itself when not needed.
  751. config DMI
  752. default y
  753. select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
  754. bool "Enable DMI scanning" if EXPERT
  755. ---help---
  756. Enabled scanning of DMI to identify machine quirks. Say Y
  757. here unless you have verified that your setup is not
  758. affected by entries in the DMI blacklist. Required by PNP
  759. BIOS code.
  760. config GART_IOMMU
  761. bool "Old AMD GART IOMMU support"
  762. select IOMMU_HELPER
  763. select SWIOTLB
  764. depends on X86_64 && PCI && AMD_NB
  765. ---help---
  766. Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
  767. GART based hardware IOMMUs.
  768. The GART supports full DMA access for devices with 32-bit access
  769. limitations, on systems with more than 3 GB. This is usually needed
  770. for USB, sound, many IDE/SATA chipsets and some other devices.
  771. Newer systems typically have a modern AMD IOMMU, supported via
  772. the CONFIG_AMD_IOMMU=y config option.
  773. In normal configurations this driver is only active when needed:
  774. there's more than 3 GB of memory and the system contains a
  775. 32-bit limited device.
  776. If unsure, say Y.
  777. config CALGARY_IOMMU
  778. bool "IBM Calgary IOMMU support"
  779. select IOMMU_HELPER
  780. select SWIOTLB
  781. depends on X86_64 && PCI
  782. ---help---
  783. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  784. systems. Needed to run systems with more than 3GB of memory
  785. properly with 32-bit PCI devices that do not support DAC
  786. (Double Address Cycle). Calgary also supports bus level
  787. isolation, where all DMAs pass through the IOMMU. This
  788. prevents them from going anywhere except their intended
  789. destination. This catches hard-to-find kernel bugs and
  790. mis-behaving drivers and devices that do not use the DMA-API
  791. properly to set up their DMA buffers. The IOMMU can be
  792. turned off at boot time with the iommu=off parameter.
  793. Normally the kernel will make the right choice by itself.
  794. If unsure, say Y.
  795. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  796. def_bool y
  797. prompt "Should Calgary be enabled by default?"
  798. depends on CALGARY_IOMMU
  799. ---help---
  800. Should Calgary be enabled by default? if you choose 'y', Calgary
  801. will be used (if it exists). If you choose 'n', Calgary will not be
  802. used even if it exists. If you choose 'n' and would like to use
  803. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  804. If unsure, say Y.
  805. config MAXSMP
  806. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  807. depends on X86_64 && SMP && DEBUG_KERNEL
  808. select CPUMASK_OFFSTACK
  809. ---help---
  810. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  811. If unsure, say N.
  812. #
  813. # The maximum number of CPUs supported:
  814. #
  815. # The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
  816. # and which can be configured interactively in the
  817. # [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
  818. #
  819. # The ranges are different on 32-bit and 64-bit kernels, depending on
  820. # hardware capabilities and scalability features of the kernel.
  821. #
  822. # ( If MAXSMP is enabled we just use the highest possible value and disable
  823. # interactive configuration. )
  824. #
  825. config NR_CPUS_RANGE_BEGIN
  826. int
  827. default NR_CPUS_RANGE_END if MAXSMP
  828. default 1 if !SMP
  829. default 2
  830. config NR_CPUS_RANGE_END
  831. int
  832. depends on X86_32
  833. default 64 if SMP && X86_BIGSMP
  834. default 8 if SMP && !X86_BIGSMP
  835. default 1 if !SMP
  836. config NR_CPUS_RANGE_END
  837. int
  838. depends on X86_64
  839. default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
  840. default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
  841. default 1 if !SMP
  842. config NR_CPUS_DEFAULT
  843. int
  844. depends on X86_32
  845. default 32 if X86_BIGSMP
  846. default 8 if SMP
  847. default 1 if !SMP
  848. config NR_CPUS_DEFAULT
  849. int
  850. depends on X86_64
  851. default 8192 if MAXSMP
  852. default 64 if SMP
  853. default 1 if !SMP
  854. config NR_CPUS
  855. int "Maximum number of CPUs" if SMP && !MAXSMP
  856. range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
  857. default NR_CPUS_DEFAULT
  858. ---help---
  859. This allows you to specify the maximum number of CPUs which this
  860. kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
  861. supported value is 8192, otherwise the maximum value is 512. The
  862. minimum value which makes sense is 2.
  863. This is purely to save memory: each supported CPU adds about 8KB
  864. to the kernel image.
  865. config SCHED_SMT
  866. def_bool y if SMP
  867. config SCHED_MC
  868. def_bool y
  869. prompt "Multi-core scheduler support"
  870. depends on SMP
  871. ---help---
  872. Multi-core scheduler support improves the CPU scheduler's decision
  873. making when dealing with multi-core CPU chips at a cost of slightly
  874. increased overhead in some places. If unsure say N here.
  875. config SCHED_MC_PRIO
  876. bool "CPU core priorities scheduler support"
  877. depends on SCHED_MC && CPU_SUP_INTEL
  878. select X86_INTEL_PSTATE
  879. select CPU_FREQ
  880. default y
  881. ---help---
  882. Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
  883. core ordering determined at manufacturing time, which allows
  884. certain cores to reach higher turbo frequencies (when running
  885. single threaded workloads) than others.
  886. Enabling this kernel feature teaches the scheduler about
  887. the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
  888. scheduler's CPU selection logic accordingly, so that higher
  889. overall system performance can be achieved.
  890. This feature will have no effect on CPUs without this feature.
  891. If unsure say Y here.
  892. config UP_LATE_INIT
  893. def_bool y
  894. depends on !SMP && X86_LOCAL_APIC
  895. config X86_UP_APIC
  896. bool "Local APIC support on uniprocessors" if !PCI_MSI
  897. default PCI_MSI
  898. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  899. ---help---
  900. A local APIC (Advanced Programmable Interrupt Controller) is an
  901. integrated interrupt controller in the CPU. If you have a single-CPU
  902. system which has a processor with a local APIC, you can say Y here to
  903. enable and use it. If you say Y here even though your machine doesn't
  904. have a local APIC, then the kernel will still run with no slowdown at
  905. all. The local APIC supports CPU-generated self-interrupts (timer,
  906. performance counters), and the NMI watchdog which detects hard
  907. lockups.
  908. config X86_UP_IOAPIC
  909. bool "IO-APIC support on uniprocessors"
  910. depends on X86_UP_APIC
  911. ---help---
  912. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  913. SMP-capable replacement for PC-style interrupt controllers. Most
  914. SMP systems and many recent uniprocessor systems have one.
  915. If you have a single-CPU system with an IO-APIC, you can say Y here
  916. to use it. If you say Y here even though your machine doesn't have
  917. an IO-APIC, then the kernel will still run with no slowdown at all.
  918. config X86_LOCAL_APIC
  919. def_bool y
  920. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
  921. select IRQ_DOMAIN_HIERARCHY
  922. select PCI_MSI_IRQ_DOMAIN if PCI_MSI
  923. config X86_IO_APIC
  924. def_bool y
  925. depends on X86_LOCAL_APIC || X86_UP_IOAPIC
  926. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  927. bool "Reroute for broken boot IRQs"
  928. depends on X86_IO_APIC
  929. ---help---
  930. This option enables a workaround that fixes a source of
  931. spurious interrupts. This is recommended when threaded
  932. interrupt handling is used on systems where the generation of
  933. superfluous "boot interrupts" cannot be disabled.
  934. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  935. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  936. kernel does during interrupt handling). On chipsets where this
  937. boot IRQ generation cannot be disabled, this workaround keeps
  938. the original IRQ line masked so that only the equivalent "boot
  939. IRQ" is delivered to the CPUs. The workaround also tells the
  940. kernel to set up the IRQ handler on the boot IRQ line. In this
  941. way only one interrupt is delivered to the kernel. Otherwise
  942. the spurious second interrupt may cause the kernel to bring
  943. down (vital) interrupt lines.
  944. Only affects "broken" chipsets. Interrupt sharing may be
  945. increased on these systems.
  946. config X86_MCE
  947. bool "Machine Check / overheating reporting"
  948. select GENERIC_ALLOCATOR
  949. default y
  950. ---help---
  951. Machine Check support allows the processor to notify the
  952. kernel if it detects a problem (e.g. overheating, data corruption).
  953. The action the kernel takes depends on the severity of the problem,
  954. ranging from warning messages to halting the machine.
  955. config X86_MCELOG_LEGACY
  956. bool "Support for deprecated /dev/mcelog character device"
  957. depends on X86_MCE
  958. ---help---
  959. Enable support for /dev/mcelog which is needed by the old mcelog
  960. userspace logging daemon. Consider switching to the new generation
  961. rasdaemon solution.
  962. config X86_MCE_INTEL
  963. def_bool y
  964. prompt "Intel MCE features"
  965. depends on X86_MCE && X86_LOCAL_APIC
  966. ---help---
  967. Additional support for intel specific MCE features such as
  968. the thermal monitor.
  969. config X86_MCE_AMD
  970. def_bool y
  971. prompt "AMD MCE features"
  972. depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
  973. ---help---
  974. Additional support for AMD specific MCE features such as
  975. the DRAM Error Threshold.
  976. config X86_ANCIENT_MCE
  977. bool "Support for old Pentium 5 / WinChip machine checks"
  978. depends on X86_32 && X86_MCE
  979. ---help---
  980. Include support for machine check handling on old Pentium 5 or WinChip
  981. systems. These typically need to be enabled explicitly on the command
  982. line.
  983. config X86_MCE_THRESHOLD
  984. depends on X86_MCE_AMD || X86_MCE_INTEL
  985. def_bool y
  986. config X86_MCE_INJECT
  987. depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
  988. tristate "Machine check injector support"
  989. ---help---
  990. Provide support for injecting machine checks for testing purposes.
  991. If you don't know what a machine check is and you don't do kernel
  992. QA it is safe to say n.
  993. config X86_THERMAL_VECTOR
  994. def_bool y
  995. depends on X86_MCE_INTEL
  996. source "arch/x86/events/Kconfig"
  997. config X86_LEGACY_VM86
  998. bool "Legacy VM86 support"
  999. depends on X86_32
  1000. ---help---
  1001. This option allows user programs to put the CPU into V8086
  1002. mode, which is an 80286-era approximation of 16-bit real mode.
  1003. Some very old versions of X and/or vbetool require this option
  1004. for user mode setting. Similarly, DOSEMU will use it if
  1005. available to accelerate real mode DOS programs. However, any
  1006. recent version of DOSEMU, X, or vbetool should be fully
  1007. functional even without kernel VM86 support, as they will all
  1008. fall back to software emulation. Nevertheless, if you are using
  1009. a 16-bit DOS program where 16-bit performance matters, vm86
  1010. mode might be faster than emulation and you might want to
  1011. enable this option.
  1012. Note that any app that works on a 64-bit kernel is unlikely to
  1013. need this option, as 64-bit kernels don't, and can't, support
  1014. V8086 mode. This option is also unrelated to 16-bit protected
  1015. mode and is not needed to run most 16-bit programs under Wine.
  1016. Enabling this option increases the complexity of the kernel
  1017. and slows down exception handling a tiny bit.
  1018. If unsure, say N here.
  1019. config VM86
  1020. bool
  1021. default X86_LEGACY_VM86
  1022. config X86_16BIT
  1023. bool "Enable support for 16-bit segments" if EXPERT
  1024. default y
  1025. depends on MODIFY_LDT_SYSCALL
  1026. ---help---
  1027. This option is required by programs like Wine to run 16-bit
  1028. protected mode legacy code on x86 processors. Disabling
  1029. this option saves about 300 bytes on i386, or around 6K text
  1030. plus 16K runtime memory on x86-64,
  1031. config X86_ESPFIX32
  1032. def_bool y
  1033. depends on X86_16BIT && X86_32
  1034. config X86_ESPFIX64
  1035. def_bool y
  1036. depends on X86_16BIT && X86_64
  1037. config X86_VSYSCALL_EMULATION
  1038. bool "Enable vsyscall emulation" if EXPERT
  1039. default y
  1040. depends on X86_64
  1041. ---help---
  1042. This enables emulation of the legacy vsyscall page. Disabling
  1043. it is roughly equivalent to booting with vsyscall=none, except
  1044. that it will also disable the helpful warning if a program
  1045. tries to use a vsyscall. With this option set to N, offending
  1046. programs will just segfault, citing addresses of the form
  1047. 0xffffffffff600?00.
  1048. This option is required by many programs built before 2013, and
  1049. care should be used even with newer programs if set to N.
  1050. Disabling this option saves about 7K of kernel size and
  1051. possibly 4K of additional runtime pagetable memory.
  1052. config TOSHIBA
  1053. tristate "Toshiba Laptop support"
  1054. depends on X86_32
  1055. ---help---
  1056. This adds a driver to safely access the System Management Mode of
  1057. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  1058. not work on models with a Phoenix BIOS. The System Management Mode
  1059. is used to set the BIOS and power saving options on Toshiba portables.
  1060. For information on utilities to make use of this driver see the
  1061. Toshiba Linux utilities web site at:
  1062. <http://www.buzzard.org.uk/toshiba/>.
  1063. Say Y if you intend to run this kernel on a Toshiba portable.
  1064. Say N otherwise.
  1065. config I8K
  1066. tristate "Dell i8k legacy laptop support"
  1067. select HWMON
  1068. select SENSORS_DELL_SMM
  1069. ---help---
  1070. This option enables legacy /proc/i8k userspace interface in hwmon
  1071. dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
  1072. temperature and allows controlling fan speeds of Dell laptops via
  1073. System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
  1074. it reports also power and hotkey status. For fan speed control is
  1075. needed userspace package i8kutils.
  1076. Say Y if you intend to run this kernel on old Dell laptops or want to
  1077. use userspace package i8kutils.
  1078. Say N otherwise.
  1079. config X86_REBOOTFIXUPS
  1080. bool "Enable X86 board specific fixups for reboot"
  1081. depends on X86_32
  1082. ---help---
  1083. This enables chipset and/or board specific fixups to be done
  1084. in order to get reboot to work correctly. This is only needed on
  1085. some combinations of hardware and BIOS. The symptom, for which
  1086. this config is intended, is when reboot ends with a stalled/hung
  1087. system.
  1088. Currently, the only fixup is for the Geode machines using
  1089. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  1090. Say Y if you want to enable the fixup. Currently, it's safe to
  1091. enable this option even if you don't need it.
  1092. Say N otherwise.
  1093. config MICROCODE
  1094. bool "CPU microcode loading support"
  1095. default y
  1096. depends on CPU_SUP_AMD || CPU_SUP_INTEL
  1097. select FW_LOADER
  1098. ---help---
  1099. If you say Y here, you will be able to update the microcode on
  1100. Intel and AMD processors. The Intel support is for the IA32 family,
  1101. e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
  1102. AMD support is for families 0x10 and later. You will obviously need
  1103. the actual microcode binary data itself which is not shipped with
  1104. the Linux kernel.
  1105. The preferred method to load microcode from a detached initrd is described
  1106. in Documentation/x86/microcode.txt. For that you need to enable
  1107. CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
  1108. initrd for microcode blobs.
  1109. In addition, you can build the microcode into the kernel. For that you
  1110. need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
  1111. config option.
  1112. config MICROCODE_INTEL
  1113. bool "Intel microcode loading support"
  1114. depends on MICROCODE
  1115. default MICROCODE
  1116. select FW_LOADER
  1117. ---help---
  1118. This options enables microcode patch loading support for Intel
  1119. processors.
  1120. For the current Intel microcode data package go to
  1121. <https://downloadcenter.intel.com> and search for
  1122. 'Linux Processor Microcode Data File'.
  1123. config MICROCODE_AMD
  1124. bool "AMD microcode loading support"
  1125. depends on MICROCODE
  1126. select FW_LOADER
  1127. ---help---
  1128. If you select this option, microcode patch loading support for AMD
  1129. processors will be enabled.
  1130. config MICROCODE_OLD_INTERFACE
  1131. def_bool y
  1132. depends on MICROCODE
  1133. config X86_MSR
  1134. tristate "/dev/cpu/*/msr - Model-specific register support"
  1135. ---help---
  1136. This device gives privileged processes access to the x86
  1137. Model-Specific Registers (MSRs). It is a character device with
  1138. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  1139. MSR accesses are directed to a specific CPU on multi-processor
  1140. systems.
  1141. config X86_CPUID
  1142. tristate "/dev/cpu/*/cpuid - CPU information support"
  1143. ---help---
  1144. This device gives processes access to the x86 CPUID instruction to
  1145. be executed on a specific processor. It is a character device
  1146. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  1147. /dev/cpu/31/cpuid.
  1148. choice
  1149. prompt "High Memory Support"
  1150. default HIGHMEM4G
  1151. depends on X86_32
  1152. config NOHIGHMEM
  1153. bool "off"
  1154. ---help---
  1155. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  1156. However, the address space of 32-bit x86 processors is only 4
  1157. Gigabytes large. That means that, if you have a large amount of
  1158. physical memory, not all of it can be "permanently mapped" by the
  1159. kernel. The physical memory that's not permanently mapped is called
  1160. "high memory".
  1161. If you are compiling a kernel which will never run on a machine with
  1162. more than 1 Gigabyte total physical RAM, answer "off" here (default
  1163. choice and suitable for most users). This will result in a "3GB/1GB"
  1164. split: 3GB are mapped so that each process sees a 3GB virtual memory
  1165. space and the remaining part of the 4GB virtual memory space is used
  1166. by the kernel to permanently map as much physical memory as
  1167. possible.
  1168. If the machine has between 1 and 4 Gigabytes physical RAM, then
  1169. answer "4GB" here.
  1170. If more than 4 Gigabytes is used then answer "64GB" here. This
  1171. selection turns Intel PAE (Physical Address Extension) mode on.
  1172. PAE implements 3-level paging on IA32 processors. PAE is fully
  1173. supported by Linux, PAE mode is implemented on all recent Intel
  1174. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  1175. then the kernel will not boot on CPUs that don't support PAE!
  1176. The actual amount of total physical memory will either be
  1177. auto detected or can be forced by using a kernel command line option
  1178. such as "mem=256M". (Try "man bootparam" or see the documentation of
  1179. your boot loader (lilo or loadlin) about how to pass options to the
  1180. kernel at boot time.)
  1181. If unsure, say "off".
  1182. config HIGHMEM4G
  1183. bool "4GB"
  1184. ---help---
  1185. Select this if you have a 32-bit processor and between 1 and 4
  1186. gigabytes of physical RAM.
  1187. config HIGHMEM64G
  1188. bool "64GB"
  1189. depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
  1190. select X86_PAE
  1191. ---help---
  1192. Select this if you have a 32-bit processor and more than 4
  1193. gigabytes of physical RAM.
  1194. endchoice
  1195. choice
  1196. prompt "Memory split" if EXPERT
  1197. default VMSPLIT_3G
  1198. depends on X86_32
  1199. ---help---
  1200. Select the desired split between kernel and user memory.
  1201. If the address range available to the kernel is less than the
  1202. physical memory installed, the remaining memory will be available
  1203. as "high memory". Accessing high memory is a little more costly
  1204. than low memory, as it needs to be mapped into the kernel first.
  1205. Note that increasing the kernel address space limits the range
  1206. available to user programs, making the address space there
  1207. tighter. Selecting anything other than the default 3G/1G split
  1208. will also likely make your kernel incompatible with binary-only
  1209. kernel modules.
  1210. If you are not absolutely sure what you are doing, leave this
  1211. option alone!
  1212. config VMSPLIT_3G
  1213. bool "3G/1G user/kernel split"
  1214. config VMSPLIT_3G_OPT
  1215. depends on !X86_PAE
  1216. bool "3G/1G user/kernel split (for full 1G low memory)"
  1217. config VMSPLIT_2G
  1218. bool "2G/2G user/kernel split"
  1219. config VMSPLIT_2G_OPT
  1220. depends on !X86_PAE
  1221. bool "2G/2G user/kernel split (for full 2G low memory)"
  1222. config VMSPLIT_1G
  1223. bool "1G/3G user/kernel split"
  1224. endchoice
  1225. config PAGE_OFFSET
  1226. hex
  1227. default 0xB0000000 if VMSPLIT_3G_OPT
  1228. default 0x80000000 if VMSPLIT_2G
  1229. default 0x78000000 if VMSPLIT_2G_OPT
  1230. default 0x40000000 if VMSPLIT_1G
  1231. default 0xC0000000
  1232. depends on X86_32
  1233. config HIGHMEM
  1234. def_bool y
  1235. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  1236. config X86_PAE
  1237. bool "PAE (Physical Address Extension) Support"
  1238. depends on X86_32 && !HIGHMEM4G
  1239. select PHYS_ADDR_T_64BIT
  1240. select SWIOTLB
  1241. ---help---
  1242. PAE is required for NX support, and furthermore enables
  1243. larger swapspace support for non-overcommit purposes. It
  1244. has the cost of more pagetable lookup overhead, and also
  1245. consumes more pagetable space per process.
  1246. config X86_5LEVEL
  1247. bool "Enable 5-level page tables support"
  1248. select DYNAMIC_MEMORY_LAYOUT
  1249. select SPARSEMEM_VMEMMAP
  1250. depends on X86_64
  1251. ---help---
  1252. 5-level paging enables access to larger address space:
  1253. upto 128 PiB of virtual address space and 4 PiB of
  1254. physical address space.
  1255. It will be supported by future Intel CPUs.
  1256. A kernel with the option enabled can be booted on machines that
  1257. support 4- or 5-level paging.
  1258. See Documentation/x86/x86_64/5level-paging.txt for more
  1259. information.
  1260. Say N if unsure.
  1261. config X86_DIRECT_GBPAGES
  1262. def_bool y
  1263. depends on X86_64 && !DEBUG_PAGEALLOC
  1264. ---help---
  1265. Certain kernel features effectively disable kernel
  1266. linear 1 GB mappings (even if the CPU otherwise
  1267. supports them), so don't confuse the user by printing
  1268. that we have them enabled.
  1269. config X86_CPA_STATISTICS
  1270. bool "Enable statistic for Change Page Attribute"
  1271. depends on DEBUG_FS
  1272. ---help---
  1273. Expose statistics about the Change Page Attribute mechanims, which
  1274. helps to determine the effectivness of preserving large and huge
  1275. page mappings when mapping protections are changed.
  1276. config ARCH_HAS_MEM_ENCRYPT
  1277. def_bool y
  1278. config AMD_MEM_ENCRYPT
  1279. bool "AMD Secure Memory Encryption (SME) support"
  1280. depends on X86_64 && CPU_SUP_AMD
  1281. select DYNAMIC_PHYSICAL_MASK
  1282. ---help---
  1283. Say yes to enable support for the encryption of system memory.
  1284. This requires an AMD processor that supports Secure Memory
  1285. Encryption (SME).
  1286. config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
  1287. bool "Activate AMD Secure Memory Encryption (SME) by default"
  1288. default y
  1289. depends on AMD_MEM_ENCRYPT
  1290. ---help---
  1291. Say yes to have system memory encrypted by default if running on
  1292. an AMD processor that supports Secure Memory Encryption (SME).
  1293. If set to Y, then the encryption of system memory can be
  1294. deactivated with the mem_encrypt=off command line option.
  1295. If set to N, then the encryption of system memory can be
  1296. activated with the mem_encrypt=on command line option.
  1297. config ARCH_USE_MEMREMAP_PROT
  1298. def_bool y
  1299. depends on AMD_MEM_ENCRYPT
  1300. # Common NUMA Features
  1301. config NUMA
  1302. bool "Numa Memory Allocation and Scheduler Support"
  1303. depends on SMP
  1304. depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
  1305. default y if X86_BIGSMP
  1306. ---help---
  1307. Enable NUMA (Non Uniform Memory Access) support.
  1308. The kernel will try to allocate memory used by a CPU on the
  1309. local memory controller of the CPU and add some more
  1310. NUMA awareness to the kernel.
  1311. For 64-bit this is recommended if the system is Intel Core i7
  1312. (or later), AMD Opteron, or EM64T NUMA.
  1313. For 32-bit this is only needed if you boot a 32-bit
  1314. kernel on a 64-bit NUMA platform.
  1315. Otherwise, you should say N.
  1316. config AMD_NUMA
  1317. def_bool y
  1318. prompt "Old style AMD Opteron NUMA detection"
  1319. depends on X86_64 && NUMA && PCI
  1320. ---help---
  1321. Enable AMD NUMA node topology detection. You should say Y here if
  1322. you have a multi processor AMD system. This uses an old method to
  1323. read the NUMA configuration directly from the builtin Northbridge
  1324. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  1325. which also takes priority if both are compiled in.
  1326. config X86_64_ACPI_NUMA
  1327. def_bool y
  1328. prompt "ACPI NUMA detection"
  1329. depends on X86_64 && NUMA && ACPI && PCI
  1330. select ACPI_NUMA
  1331. ---help---
  1332. Enable ACPI SRAT based node topology detection.
  1333. # Some NUMA nodes have memory ranges that span
  1334. # other nodes. Even though a pfn is valid and
  1335. # between a node's start and end pfns, it may not
  1336. # reside on that node. See memmap_init_zone()
  1337. # for details.
  1338. config NODES_SPAN_OTHER_NODES
  1339. def_bool y
  1340. depends on X86_64_ACPI_NUMA
  1341. config NUMA_EMU
  1342. bool "NUMA emulation"
  1343. depends on NUMA
  1344. ---help---
  1345. Enable NUMA emulation. A flat machine will be split
  1346. into virtual nodes when booted with "numa=fake=N", where N is the
  1347. number of nodes. This is only useful for debugging.
  1348. config NODES_SHIFT
  1349. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1350. range 1 10
  1351. default "10" if MAXSMP
  1352. default "6" if X86_64
  1353. default "3"
  1354. depends on NEED_MULTIPLE_NODES
  1355. ---help---
  1356. Specify the maximum number of NUMA Nodes available on the target
  1357. system. Increases memory reserved to accommodate various tables.
  1358. config ARCH_HAVE_MEMORY_PRESENT
  1359. def_bool y
  1360. depends on X86_32 && DISCONTIGMEM
  1361. config ARCH_FLATMEM_ENABLE
  1362. def_bool y
  1363. depends on X86_32 && !NUMA
  1364. config ARCH_DISCONTIGMEM_ENABLE
  1365. def_bool y
  1366. depends on NUMA && X86_32
  1367. config ARCH_DISCONTIGMEM_DEFAULT
  1368. def_bool y
  1369. depends on NUMA && X86_32
  1370. config ARCH_SPARSEMEM_ENABLE
  1371. def_bool y
  1372. depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
  1373. select SPARSEMEM_STATIC if X86_32
  1374. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1375. config ARCH_SPARSEMEM_DEFAULT
  1376. def_bool y
  1377. depends on X86_64
  1378. config ARCH_SELECT_MEMORY_MODEL
  1379. def_bool y
  1380. depends on ARCH_SPARSEMEM_ENABLE
  1381. config ARCH_MEMORY_PROBE
  1382. bool "Enable sysfs memory/probe interface"
  1383. depends on X86_64 && MEMORY_HOTPLUG
  1384. help
  1385. This option enables a sysfs memory/probe interface for testing.
  1386. See Documentation/memory-hotplug.txt for more information.
  1387. If you are unsure how to answer this question, answer N.
  1388. config ARCH_PROC_KCORE_TEXT
  1389. def_bool y
  1390. depends on X86_64 && PROC_KCORE
  1391. config ILLEGAL_POINTER_VALUE
  1392. hex
  1393. default 0 if X86_32
  1394. default 0xdead000000000000 if X86_64
  1395. config X86_PMEM_LEGACY_DEVICE
  1396. bool
  1397. config X86_PMEM_LEGACY
  1398. tristate "Support non-standard NVDIMMs and ADR protected memory"
  1399. depends on PHYS_ADDR_T_64BIT
  1400. depends on BLK_DEV
  1401. select X86_PMEM_LEGACY_DEVICE
  1402. select LIBNVDIMM
  1403. help
  1404. Treat memory marked using the non-standard e820 type of 12 as used
  1405. by the Intel Sandy Bridge-EP reference BIOS as protected memory.
  1406. The kernel will offer these regions to the 'pmem' driver so
  1407. they can be used for persistent storage.
  1408. Say Y if unsure.
  1409. config HIGHPTE
  1410. bool "Allocate 3rd-level pagetables from highmem"
  1411. depends on HIGHMEM
  1412. ---help---
  1413. The VM uses one page table entry for each page of physical memory.
  1414. For systems with a lot of RAM, this can be wasteful of precious
  1415. low memory. Setting this option will put user-space page table
  1416. entries in high memory.
  1417. config X86_CHECK_BIOS_CORRUPTION
  1418. bool "Check for low memory corruption"
  1419. ---help---
  1420. Periodically check for memory corruption in low memory, which
  1421. is suspected to be caused by BIOS. Even when enabled in the
  1422. configuration, it is disabled at runtime. Enable it by
  1423. setting "memory_corruption_check=1" on the kernel command
  1424. line. By default it scans the low 64k of memory every 60
  1425. seconds; see the memory_corruption_check_size and
  1426. memory_corruption_check_period parameters in
  1427. Documentation/admin-guide/kernel-parameters.rst to adjust this.
  1428. When enabled with the default parameters, this option has
  1429. almost no overhead, as it reserves a relatively small amount
  1430. of memory and scans it infrequently. It both detects corruption
  1431. and prevents it from affecting the running system.
  1432. It is, however, intended as a diagnostic tool; if repeatable
  1433. BIOS-originated corruption always affects the same memory,
  1434. you can use memmap= to prevent the kernel from using that
  1435. memory.
  1436. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1437. bool "Set the default setting of memory_corruption_check"
  1438. depends on X86_CHECK_BIOS_CORRUPTION
  1439. default y
  1440. ---help---
  1441. Set whether the default state of memory_corruption_check is
  1442. on or off.
  1443. config X86_RESERVE_LOW
  1444. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1445. default 64
  1446. range 4 640
  1447. ---help---
  1448. Specify the amount of low memory to reserve for the BIOS.
  1449. The first page contains BIOS data structures that the kernel
  1450. must not use, so that page must always be reserved.
  1451. By default we reserve the first 64K of physical RAM, as a
  1452. number of BIOSes are known to corrupt that memory range
  1453. during events such as suspend/resume or monitor cable
  1454. insertion, so it must not be used by the kernel.
  1455. You can set this to 4 if you are absolutely sure that you
  1456. trust the BIOS to get all its memory reservations and usages
  1457. right. If you know your BIOS have problems beyond the
  1458. default 64K area, you can set this to 640 to avoid using the
  1459. entire low memory range.
  1460. If you have doubts about the BIOS (e.g. suspend/resume does
  1461. not work or there's kernel crashes after certain hardware
  1462. hotplug events) then you might want to enable
  1463. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1464. typical corruption patterns.
  1465. Leave this to the default value of 64 if you are unsure.
  1466. config MATH_EMULATION
  1467. bool
  1468. depends on MODIFY_LDT_SYSCALL
  1469. prompt "Math emulation" if X86_32
  1470. ---help---
  1471. Linux can emulate a math coprocessor (used for floating point
  1472. operations) if you don't have one. 486DX and Pentium processors have
  1473. a math coprocessor built in, 486SX and 386 do not, unless you added
  1474. a 487DX or 387, respectively. (The messages during boot time can
  1475. give you some hints here ["man dmesg"].) Everyone needs either a
  1476. coprocessor or this emulation.
  1477. If you don't have a math coprocessor, you need to say Y here; if you
  1478. say Y here even though you have a coprocessor, the coprocessor will
  1479. be used nevertheless. (This behavior can be changed with the kernel
  1480. command line option "no387", which comes handy if your coprocessor
  1481. is broken. Try "man bootparam" or see the documentation of your boot
  1482. loader (lilo or loadlin) about how to pass options to the kernel at
  1483. boot time.) This means that it is a good idea to say Y here if you
  1484. intend to use this kernel on different machines.
  1485. More information about the internals of the Linux math coprocessor
  1486. emulation can be found in <file:arch/x86/math-emu/README>.
  1487. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1488. kernel, it won't hurt.
  1489. config MTRR
  1490. def_bool y
  1491. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1492. ---help---
  1493. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1494. the Memory Type Range Registers (MTRRs) may be used to control
  1495. processor access to memory ranges. This is most useful if you have
  1496. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1497. allows bus write transfers to be combined into a larger transfer
  1498. before bursting over the PCI/AGP bus. This can increase performance
  1499. of image write operations 2.5 times or more. Saying Y here creates a
  1500. /proc/mtrr file which may be used to manipulate your processor's
  1501. MTRRs. Typically the X server should use this.
  1502. This code has a reasonably generic interface so that similar
  1503. control registers on other processors can be easily supported
  1504. as well:
  1505. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1506. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1507. these, the ARRs are used to emulate the MTRRs.
  1508. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1509. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1510. write-combining. All of these processors are supported by this code
  1511. and it makes sense to say Y here if you have one of them.
  1512. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1513. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1514. can lead to all sorts of problems, so it's good to say Y here.
  1515. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1516. just add about 9 KB to your kernel.
  1517. See <file:Documentation/x86/mtrr.txt> for more information.
  1518. config MTRR_SANITIZER
  1519. def_bool y
  1520. prompt "MTRR cleanup support"
  1521. depends on MTRR
  1522. ---help---
  1523. Convert MTRR layout from continuous to discrete, so X drivers can
  1524. add writeback entries.
  1525. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1526. The largest mtrr entry size for a continuous block can be set with
  1527. mtrr_chunk_size.
  1528. If unsure, say Y.
  1529. config MTRR_SANITIZER_ENABLE_DEFAULT
  1530. int "MTRR cleanup enable value (0-1)"
  1531. range 0 1
  1532. default "0"
  1533. depends on MTRR_SANITIZER
  1534. ---help---
  1535. Enable mtrr cleanup default value
  1536. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1537. int "MTRR cleanup spare reg num (0-7)"
  1538. range 0 7
  1539. default "1"
  1540. depends on MTRR_SANITIZER
  1541. ---help---
  1542. mtrr cleanup spare entries default, it can be changed via
  1543. mtrr_spare_reg_nr=N on the kernel command line.
  1544. config X86_PAT
  1545. def_bool y
  1546. prompt "x86 PAT support" if EXPERT
  1547. depends on MTRR
  1548. ---help---
  1549. Use PAT attributes to setup page level cache control.
  1550. PATs are the modern equivalents of MTRRs and are much more
  1551. flexible than MTRRs.
  1552. Say N here if you see bootup problems (boot crash, boot hang,
  1553. spontaneous reboots) or a non-working video driver.
  1554. If unsure, say Y.
  1555. config ARCH_USES_PG_UNCACHED
  1556. def_bool y
  1557. depends on X86_PAT
  1558. config ARCH_RANDOM
  1559. def_bool y
  1560. prompt "x86 architectural random number generator" if EXPERT
  1561. ---help---
  1562. Enable the x86 architectural RDRAND instruction
  1563. (Intel Bull Mountain technology) to generate random numbers.
  1564. If supported, this is a high bandwidth, cryptographically
  1565. secure hardware random number generator.
  1566. config X86_SMAP
  1567. def_bool y
  1568. prompt "Supervisor Mode Access Prevention" if EXPERT
  1569. ---help---
  1570. Supervisor Mode Access Prevention (SMAP) is a security
  1571. feature in newer Intel processors. There is a small
  1572. performance cost if this enabled and turned on; there is
  1573. also a small increase in the kernel size if this is enabled.
  1574. If unsure, say Y.
  1575. config X86_INTEL_UMIP
  1576. def_bool y
  1577. depends on CPU_SUP_INTEL
  1578. prompt "Intel User Mode Instruction Prevention" if EXPERT
  1579. ---help---
  1580. The User Mode Instruction Prevention (UMIP) is a security
  1581. feature in newer Intel processors. If enabled, a general
  1582. protection fault is issued if the SGDT, SLDT, SIDT, SMSW
  1583. or STR instructions are executed in user mode. These instructions
  1584. unnecessarily expose information about the hardware state.
  1585. The vast majority of applications do not use these instructions.
  1586. For the very few that do, software emulation is provided in
  1587. specific cases in protected and virtual-8086 modes. Emulated
  1588. results are dummy.
  1589. config X86_INTEL_MPX
  1590. prompt "Intel MPX (Memory Protection Extensions)"
  1591. def_bool n
  1592. # Note: only available in 64-bit mode due to VMA flags shortage
  1593. depends on CPU_SUP_INTEL && X86_64
  1594. select ARCH_USES_HIGH_VMA_FLAGS
  1595. ---help---
  1596. MPX provides hardware features that can be used in
  1597. conjunction with compiler-instrumented code to check
  1598. memory references. It is designed to detect buffer
  1599. overflow or underflow bugs.
  1600. This option enables running applications which are
  1601. instrumented or otherwise use MPX. It does not use MPX
  1602. itself inside the kernel or to protect the kernel
  1603. against bad memory references.
  1604. Enabling this option will make the kernel larger:
  1605. ~8k of kernel text and 36 bytes of data on a 64-bit
  1606. defconfig. It adds a long to the 'mm_struct' which
  1607. will increase the kernel memory overhead of each
  1608. process and adds some branches to paths used during
  1609. exec() and munmap().
  1610. For details, see Documentation/x86/intel_mpx.txt
  1611. If unsure, say N.
  1612. config X86_INTEL_MEMORY_PROTECTION_KEYS
  1613. prompt "Intel Memory Protection Keys"
  1614. def_bool y
  1615. # Note: only available in 64-bit mode
  1616. depends on CPU_SUP_INTEL && X86_64
  1617. select ARCH_USES_HIGH_VMA_FLAGS
  1618. select ARCH_HAS_PKEYS
  1619. ---help---
  1620. Memory Protection Keys provides a mechanism for enforcing
  1621. page-based protections, but without requiring modification of the
  1622. page tables when an application changes protection domains.
  1623. For details, see Documentation/x86/protection-keys.txt
  1624. If unsure, say y.
  1625. config EFI
  1626. bool "EFI runtime service support"
  1627. depends on ACPI
  1628. select UCS2_STRING
  1629. select EFI_RUNTIME_WRAPPERS
  1630. ---help---
  1631. This enables the kernel to use EFI runtime services that are
  1632. available (such as the EFI variable services).
  1633. This option is only useful on systems that have EFI firmware.
  1634. In addition, you should use the latest ELILO loader available
  1635. at <http://elilo.sourceforge.net> in order to take advantage
  1636. of EFI runtime services. However, even with this option, the
  1637. resultant kernel should continue to boot on existing non-EFI
  1638. platforms.
  1639. config EFI_STUB
  1640. bool "EFI stub support"
  1641. depends on EFI && !X86_USE_3DNOW
  1642. select RELOCATABLE
  1643. ---help---
  1644. This kernel feature allows a bzImage to be loaded directly
  1645. by EFI firmware without the use of a bootloader.
  1646. See Documentation/efi-stub.txt for more information.
  1647. config EFI_MIXED
  1648. bool "EFI mixed-mode support"
  1649. depends on EFI_STUB && X86_64
  1650. ---help---
  1651. Enabling this feature allows a 64-bit kernel to be booted
  1652. on a 32-bit firmware, provided that your CPU supports 64-bit
  1653. mode.
  1654. Note that it is not possible to boot a mixed-mode enabled
  1655. kernel via the EFI boot stub - a bootloader that supports
  1656. the EFI handover protocol must be used.
  1657. If unsure, say N.
  1658. config SECCOMP
  1659. def_bool y
  1660. prompt "Enable seccomp to safely compute untrusted bytecode"
  1661. ---help---
  1662. This kernel feature is useful for number crunching applications
  1663. that may need to compute untrusted bytecode during their
  1664. execution. By using pipes or other transports made available to
  1665. the process as file descriptors supporting the read/write
  1666. syscalls, it's possible to isolate those applications in
  1667. their own address space using seccomp. Once seccomp is
  1668. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1669. and the task is only allowed to execute a few safe syscalls
  1670. defined by each seccomp mode.
  1671. If unsure, say Y. Only embedded should say N here.
  1672. source kernel/Kconfig.hz
  1673. config KEXEC
  1674. bool "kexec system call"
  1675. select KEXEC_CORE
  1676. ---help---
  1677. kexec is a system call that implements the ability to shutdown your
  1678. current kernel, and to start another kernel. It is like a reboot
  1679. but it is independent of the system firmware. And like a reboot
  1680. you can start any kernel with it, not just Linux.
  1681. The name comes from the similarity to the exec system call.
  1682. It is an ongoing process to be certain the hardware in a machine
  1683. is properly shutdown, so do not be surprised if this code does not
  1684. initially work for you. As of this writing the exact hardware
  1685. interface is strongly in flux, so no good recommendation can be
  1686. made.
  1687. config KEXEC_FILE
  1688. bool "kexec file based system call"
  1689. select KEXEC_CORE
  1690. select BUILD_BIN2C
  1691. depends on X86_64
  1692. depends on CRYPTO=y
  1693. depends on CRYPTO_SHA256=y
  1694. ---help---
  1695. This is new version of kexec system call. This system call is
  1696. file based and takes file descriptors as system call argument
  1697. for kernel and initramfs as opposed to list of segments as
  1698. accepted by previous system call.
  1699. config ARCH_HAS_KEXEC_PURGATORY
  1700. def_bool KEXEC_FILE
  1701. config KEXEC_VERIFY_SIG
  1702. bool "Verify kernel signature during kexec_file_load() syscall"
  1703. depends on KEXEC_FILE
  1704. ---help---
  1705. This option makes kernel signature verification mandatory for
  1706. the kexec_file_load() syscall.
  1707. In addition to that option, you need to enable signature
  1708. verification for the corresponding kernel image type being
  1709. loaded in order for this to work.
  1710. config KEXEC_BZIMAGE_VERIFY_SIG
  1711. bool "Enable bzImage signature verification support"
  1712. depends on KEXEC_VERIFY_SIG
  1713. depends on SIGNED_PE_FILE_VERIFICATION
  1714. select SYSTEM_TRUSTED_KEYRING
  1715. ---help---
  1716. Enable bzImage signature verification support.
  1717. config CRASH_DUMP
  1718. bool "kernel crash dumps"
  1719. depends on X86_64 || (X86_32 && HIGHMEM)
  1720. ---help---
  1721. Generate crash dump after being started by kexec.
  1722. This should be normally only set in special crash dump kernels
  1723. which are loaded in the main kernel with kexec-tools into
  1724. a specially reserved region and then later executed after
  1725. a crash by kdump/kexec. The crash dump kernel must be compiled
  1726. to a memory address not used by the main kernel or BIOS using
  1727. PHYSICAL_START, or it must be built as a relocatable image
  1728. (CONFIG_RELOCATABLE=y).
  1729. For more details see Documentation/kdump/kdump.txt
  1730. config KEXEC_JUMP
  1731. bool "kexec jump"
  1732. depends on KEXEC && HIBERNATION
  1733. ---help---
  1734. Jump between original kernel and kexeced kernel and invoke
  1735. code in physical address mode via KEXEC
  1736. config PHYSICAL_START
  1737. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1738. default "0x1000000"
  1739. ---help---
  1740. This gives the physical address where the kernel is loaded.
  1741. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1742. bzImage will decompress itself to above physical address and
  1743. run from there. Otherwise, bzImage will run from the address where
  1744. it has been loaded by the boot loader and will ignore above physical
  1745. address.
  1746. In normal kdump cases one does not have to set/change this option
  1747. as now bzImage can be compiled as a completely relocatable image
  1748. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1749. address. This option is mainly useful for the folks who don't want
  1750. to use a bzImage for capturing the crash dump and want to use a
  1751. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1752. to be specifically compiled to run from a specific memory area
  1753. (normally a reserved region) and this option comes handy.
  1754. So if you are using bzImage for capturing the crash dump,
  1755. leave the value here unchanged to 0x1000000 and set
  1756. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1757. for capturing the crash dump change this value to start of
  1758. the reserved region. In other words, it can be set based on
  1759. the "X" value as specified in the "crashkernel=YM@XM"
  1760. command line boot parameter passed to the panic-ed
  1761. kernel. Please take a look at Documentation/kdump/kdump.txt
  1762. for more details about crash dumps.
  1763. Usage of bzImage for capturing the crash dump is recommended as
  1764. one does not have to build two kernels. Same kernel can be used
  1765. as production kernel and capture kernel. Above option should have
  1766. gone away after relocatable bzImage support is introduced. But it
  1767. is present because there are users out there who continue to use
  1768. vmlinux for dump capture. This option should go away down the
  1769. line.
  1770. Don't change this unless you know what you are doing.
  1771. config RELOCATABLE
  1772. bool "Build a relocatable kernel"
  1773. default y
  1774. ---help---
  1775. This builds a kernel image that retains relocation information
  1776. so it can be loaded someplace besides the default 1MB.
  1777. The relocations tend to make the kernel binary about 10% larger,
  1778. but are discarded at runtime.
  1779. One use is for the kexec on panic case where the recovery kernel
  1780. must live at a different physical address than the primary
  1781. kernel.
  1782. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1783. it has been loaded at and the compile time physical address
  1784. (CONFIG_PHYSICAL_START) is used as the minimum location.
  1785. config RANDOMIZE_BASE
  1786. bool "Randomize the address of the kernel image (KASLR)"
  1787. depends on RELOCATABLE
  1788. default y
  1789. ---help---
  1790. In support of Kernel Address Space Layout Randomization (KASLR),
  1791. this randomizes the physical address at which the kernel image
  1792. is decompressed and the virtual address where the kernel
  1793. image is mapped, as a security feature that deters exploit
  1794. attempts relying on knowledge of the location of kernel
  1795. code internals.
  1796. On 64-bit, the kernel physical and virtual addresses are
  1797. randomized separately. The physical address will be anywhere
  1798. between 16MB and the top of physical memory (up to 64TB). The
  1799. virtual address will be randomized from 16MB up to 1GB (9 bits
  1800. of entropy). Note that this also reduces the memory space
  1801. available to kernel modules from 1.5GB to 1GB.
  1802. On 32-bit, the kernel physical and virtual addresses are
  1803. randomized together. They will be randomized from 16MB up to
  1804. 512MB (8 bits of entropy).
  1805. Entropy is generated using the RDRAND instruction if it is
  1806. supported. If RDTSC is supported, its value is mixed into
  1807. the entropy pool as well. If neither RDRAND nor RDTSC are
  1808. supported, then entropy is read from the i8254 timer. The
  1809. usable entropy is limited by the kernel being built using
  1810. 2GB addressing, and that PHYSICAL_ALIGN must be at a
  1811. minimum of 2MB. As a result, only 10 bits of entropy are
  1812. theoretically possible, but the implementations are further
  1813. limited due to memory layouts.
  1814. If unsure, say Y.
  1815. # Relocation on x86 needs some additional build support
  1816. config X86_NEED_RELOCS
  1817. def_bool y
  1818. depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
  1819. config PHYSICAL_ALIGN
  1820. hex "Alignment value to which kernel should be aligned"
  1821. default "0x200000"
  1822. range 0x2000 0x1000000 if X86_32
  1823. range 0x200000 0x1000000 if X86_64
  1824. ---help---
  1825. This value puts the alignment restrictions on physical address
  1826. where kernel is loaded and run from. Kernel is compiled for an
  1827. address which meets above alignment restriction.
  1828. If bootloader loads the kernel at a non-aligned address and
  1829. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1830. address aligned to above value and run from there.
  1831. If bootloader loads the kernel at a non-aligned address and
  1832. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1833. load address and decompress itself to the address it has been
  1834. compiled for and run from there. The address for which kernel is
  1835. compiled already meets above alignment restrictions. Hence the
  1836. end result is that kernel runs from a physical address meeting
  1837. above alignment restrictions.
  1838. On 32-bit this value must be a multiple of 0x2000. On 64-bit
  1839. this value must be a multiple of 0x200000.
  1840. Don't change this unless you know what you are doing.
  1841. config DYNAMIC_MEMORY_LAYOUT
  1842. bool
  1843. ---help---
  1844. This option makes base addresses of vmalloc and vmemmap as well as
  1845. __PAGE_OFFSET movable during boot.
  1846. config RANDOMIZE_MEMORY
  1847. bool "Randomize the kernel memory sections"
  1848. depends on X86_64
  1849. depends on RANDOMIZE_BASE
  1850. select DYNAMIC_MEMORY_LAYOUT
  1851. default RANDOMIZE_BASE
  1852. ---help---
  1853. Randomizes the base virtual address of kernel memory sections
  1854. (physical memory mapping, vmalloc & vmemmap). This security feature
  1855. makes exploits relying on predictable memory locations less reliable.
  1856. The order of allocations remains unchanged. Entropy is generated in
  1857. the same way as RANDOMIZE_BASE. Current implementation in the optimal
  1858. configuration have in average 30,000 different possible virtual
  1859. addresses for each memory section.
  1860. If unsure, say Y.
  1861. config RANDOMIZE_MEMORY_PHYSICAL_PADDING
  1862. hex "Physical memory mapping padding" if EXPERT
  1863. depends on RANDOMIZE_MEMORY
  1864. default "0xa" if MEMORY_HOTPLUG
  1865. default "0x0"
  1866. range 0x1 0x40 if MEMORY_HOTPLUG
  1867. range 0x0 0x40
  1868. ---help---
  1869. Define the padding in terabytes added to the existing physical
  1870. memory size during kernel memory randomization. It is useful
  1871. for memory hotplug support but reduces the entropy available for
  1872. address randomization.
  1873. If unsure, leave at the default value.
  1874. config HOTPLUG_CPU
  1875. bool "Support for hot-pluggable CPUs"
  1876. depends on SMP
  1877. ---help---
  1878. Say Y here to allow turning CPUs off and on. CPUs can be
  1879. controlled through /sys/devices/system/cpu.
  1880. ( Note: power management support will enable this option
  1881. automatically on SMP systems. )
  1882. Say N if you want to disable CPU hotplug.
  1883. config BOOTPARAM_HOTPLUG_CPU0
  1884. bool "Set default setting of cpu0_hotpluggable"
  1885. depends on HOTPLUG_CPU
  1886. ---help---
  1887. Set whether default state of cpu0_hotpluggable is on or off.
  1888. Say Y here to enable CPU0 hotplug by default. If this switch
  1889. is turned on, there is no need to give cpu0_hotplug kernel
  1890. parameter and the CPU0 hotplug feature is enabled by default.
  1891. Please note: there are two known CPU0 dependencies if you want
  1892. to enable the CPU0 hotplug feature either by this switch or by
  1893. cpu0_hotplug kernel parameter.
  1894. First, resume from hibernate or suspend always starts from CPU0.
  1895. So hibernate and suspend are prevented if CPU0 is offline.
  1896. Second dependency is PIC interrupts always go to CPU0. CPU0 can not
  1897. offline if any interrupt can not migrate out of CPU0. There may
  1898. be other CPU0 dependencies.
  1899. Please make sure the dependencies are under your control before
  1900. you enable this feature.
  1901. Say N if you don't want to enable CPU0 hotplug feature by default.
  1902. You still can enable the CPU0 hotplug feature at boot by kernel
  1903. parameter cpu0_hotplug.
  1904. config DEBUG_HOTPLUG_CPU0
  1905. def_bool n
  1906. prompt "Debug CPU0 hotplug"
  1907. depends on HOTPLUG_CPU
  1908. ---help---
  1909. Enabling this option offlines CPU0 (if CPU0 can be offlined) as
  1910. soon as possible and boots up userspace with CPU0 offlined. User
  1911. can online CPU0 back after boot time.
  1912. To debug CPU0 hotplug, you need to enable CPU0 offline/online
  1913. feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
  1914. compilation or giving cpu0_hotplug kernel parameter at boot.
  1915. If unsure, say N.
  1916. config COMPAT_VDSO
  1917. def_bool n
  1918. prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
  1919. depends on COMPAT_32
  1920. ---help---
  1921. Certain buggy versions of glibc will crash if they are
  1922. presented with a 32-bit vDSO that is not mapped at the address
  1923. indicated in its segment table.
  1924. The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
  1925. and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
  1926. 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
  1927. the only released version with the bug, but OpenSUSE 9
  1928. contains a buggy "glibc 2.3.2".
  1929. The symptom of the bug is that everything crashes on startup, saying:
  1930. dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
  1931. Saying Y here changes the default value of the vdso32 boot
  1932. option from 1 to 0, which turns off the 32-bit vDSO entirely.
  1933. This works around the glibc bug but hurts performance.
  1934. If unsure, say N: if you are compiling your own kernel, you
  1935. are unlikely to be using a buggy version of glibc.
  1936. choice
  1937. prompt "vsyscall table for legacy applications"
  1938. depends on X86_64
  1939. default LEGACY_VSYSCALL_EMULATE
  1940. help
  1941. Legacy user code that does not know how to find the vDSO expects
  1942. to be able to issue three syscalls by calling fixed addresses in
  1943. kernel space. Since this location is not randomized with ASLR,
  1944. it can be used to assist security vulnerability exploitation.
  1945. This setting can be changed at boot time via the kernel command
  1946. line parameter vsyscall=[emulate|none].
  1947. On a system with recent enough glibc (2.14 or newer) and no
  1948. static binaries, you can say None without a performance penalty
  1949. to improve security.
  1950. If unsure, select "Emulate".
  1951. config LEGACY_VSYSCALL_EMULATE
  1952. bool "Emulate"
  1953. help
  1954. The kernel traps and emulates calls into the fixed
  1955. vsyscall address mapping. This makes the mapping
  1956. non-executable, but it still contains known contents,
  1957. which could be used in certain rare security vulnerability
  1958. exploits. This configuration is recommended when userspace
  1959. still uses the vsyscall area.
  1960. config LEGACY_VSYSCALL_NONE
  1961. bool "None"
  1962. help
  1963. There will be no vsyscall mapping at all. This will
  1964. eliminate any risk of ASLR bypass due to the vsyscall
  1965. fixed address mapping. Attempts to use the vsyscalls
  1966. will be reported to dmesg, so that either old or
  1967. malicious userspace programs can be identified.
  1968. endchoice
  1969. config CMDLINE_BOOL
  1970. bool "Built-in kernel command line"
  1971. ---help---
  1972. Allow for specifying boot arguments to the kernel at
  1973. build time. On some systems (e.g. embedded ones), it is
  1974. necessary or convenient to provide some or all of the
  1975. kernel boot arguments with the kernel itself (that is,
  1976. to not rely on the boot loader to provide them.)
  1977. To compile command line arguments into the kernel,
  1978. set this option to 'Y', then fill in the
  1979. boot arguments in CONFIG_CMDLINE.
  1980. Systems with fully functional boot loaders (i.e. non-embedded)
  1981. should leave this option set to 'N'.
  1982. config CMDLINE
  1983. string "Built-in kernel command string"
  1984. depends on CMDLINE_BOOL
  1985. default ""
  1986. ---help---
  1987. Enter arguments here that should be compiled into the kernel
  1988. image and used at boot time. If the boot loader provides a
  1989. command line at boot time, it is appended to this string to
  1990. form the full kernel command line, when the system boots.
  1991. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1992. change this behavior.
  1993. In most cases, the command line (whether built-in or provided
  1994. by the boot loader) should specify the device for the root
  1995. file system.
  1996. config CMDLINE_OVERRIDE
  1997. bool "Built-in command line overrides boot loader arguments"
  1998. depends on CMDLINE_BOOL
  1999. ---help---
  2000. Set this option to 'Y' to have the kernel ignore the boot loader
  2001. command line, and use ONLY the built-in command line.
  2002. This is used to work around broken boot loaders. This should
  2003. be set to 'N' under normal conditions.
  2004. config MODIFY_LDT_SYSCALL
  2005. bool "Enable the LDT (local descriptor table)" if EXPERT
  2006. default y
  2007. ---help---
  2008. Linux can allow user programs to install a per-process x86
  2009. Local Descriptor Table (LDT) using the modify_ldt(2) system
  2010. call. This is required to run 16-bit or segmented code such as
  2011. DOSEMU or some Wine programs. It is also used by some very old
  2012. threading libraries.
  2013. Enabling this feature adds a small amount of overhead to
  2014. context switches and increases the low-level kernel attack
  2015. surface. Disabling it removes the modify_ldt(2) system call.
  2016. Saying 'N' here may make sense for embedded or server kernels.
  2017. source "kernel/livepatch/Kconfig"
  2018. endmenu
  2019. config ARCH_HAS_ADD_PAGES
  2020. def_bool y
  2021. depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
  2022. config ARCH_ENABLE_MEMORY_HOTPLUG
  2023. def_bool y
  2024. depends on X86_64 || (X86_32 && HIGHMEM)
  2025. config ARCH_ENABLE_MEMORY_HOTREMOVE
  2026. def_bool y
  2027. depends on MEMORY_HOTPLUG
  2028. config USE_PERCPU_NUMA_NODE_ID
  2029. def_bool y
  2030. depends on NUMA
  2031. config ARCH_ENABLE_SPLIT_PMD_PTLOCK
  2032. def_bool y
  2033. depends on X86_64 || X86_PAE
  2034. config ARCH_ENABLE_HUGEPAGE_MIGRATION
  2035. def_bool y
  2036. depends on X86_64 && HUGETLB_PAGE && MIGRATION
  2037. config ARCH_ENABLE_THP_MIGRATION
  2038. def_bool y
  2039. depends on X86_64 && TRANSPARENT_HUGEPAGE
  2040. menu "Power management and ACPI options"
  2041. config ARCH_HIBERNATION_HEADER
  2042. def_bool y
  2043. depends on HIBERNATION
  2044. source "kernel/power/Kconfig"
  2045. source "drivers/acpi/Kconfig"
  2046. source "drivers/sfi/Kconfig"
  2047. config X86_APM_BOOT
  2048. def_bool y
  2049. depends on APM
  2050. menuconfig APM
  2051. tristate "APM (Advanced Power Management) BIOS support"
  2052. depends on X86_32 && PM_SLEEP
  2053. ---help---
  2054. APM is a BIOS specification for saving power using several different
  2055. techniques. This is mostly useful for battery powered laptops with
  2056. APM compliant BIOSes. If you say Y here, the system time will be
  2057. reset after a RESUME operation, the /proc/apm device will provide
  2058. battery status information, and user-space programs will receive
  2059. notification of APM "events" (e.g. battery status change).
  2060. If you select "Y" here, you can disable actual use of the APM
  2061. BIOS by passing the "apm=off" option to the kernel at boot time.
  2062. Note that the APM support is almost completely disabled for
  2063. machines with more than one CPU.
  2064. In order to use APM, you will need supporting software. For location
  2065. and more information, read <file:Documentation/power/apm-acpi.txt>
  2066. and the Battery Powered Linux mini-HOWTO, available from
  2067. <http://www.tldp.org/docs.html#howto>.
  2068. This driver does not spin down disk drives (see the hdparm(8)
  2069. manpage ("man 8 hdparm") for that), and it doesn't turn off
  2070. VESA-compliant "green" monitors.
  2071. This driver does not support the TI 4000M TravelMate and the ACER
  2072. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  2073. desktop machines also don't have compliant BIOSes, and this driver
  2074. may cause those machines to panic during the boot phase.
  2075. Generally, if you don't have a battery in your machine, there isn't
  2076. much point in using this driver and you should say N. If you get
  2077. random kernel OOPSes or reboots that don't seem to be related to
  2078. anything, try disabling/enabling this option (or disabling/enabling
  2079. APM in your BIOS).
  2080. Some other things you should try when experiencing seemingly random,
  2081. "weird" problems:
  2082. 1) make sure that you have enough swap space and that it is
  2083. enabled.
  2084. 2) pass the "no-hlt" option to the kernel
  2085. 3) switch on floating point emulation in the kernel and pass
  2086. the "no387" option to the kernel
  2087. 4) pass the "floppy=nodma" option to the kernel
  2088. 5) pass the "mem=4M" option to the kernel (thereby disabling
  2089. all but the first 4 MB of RAM)
  2090. 6) make sure that the CPU is not over clocked.
  2091. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  2092. 8) disable the cache from your BIOS settings
  2093. 9) install a fan for the video card or exchange video RAM
  2094. 10) install a better fan for the CPU
  2095. 11) exchange RAM chips
  2096. 12) exchange the motherboard.
  2097. To compile this driver as a module, choose M here: the
  2098. module will be called apm.
  2099. if APM
  2100. config APM_IGNORE_USER_SUSPEND
  2101. bool "Ignore USER SUSPEND"
  2102. ---help---
  2103. This option will ignore USER SUSPEND requests. On machines with a
  2104. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  2105. series notebooks, it is necessary to say Y because of a BIOS bug.
  2106. config APM_DO_ENABLE
  2107. bool "Enable PM at boot time"
  2108. ---help---
  2109. Enable APM features at boot time. From page 36 of the APM BIOS
  2110. specification: "When disabled, the APM BIOS does not automatically
  2111. power manage devices, enter the Standby State, enter the Suspend
  2112. State, or take power saving steps in response to CPU Idle calls."
  2113. This driver will make CPU Idle calls when Linux is idle (unless this
  2114. feature is turned off -- see "Do CPU IDLE calls", below). This
  2115. should always save battery power, but more complicated APM features
  2116. will be dependent on your BIOS implementation. You may need to turn
  2117. this option off if your computer hangs at boot time when using APM
  2118. support, or if it beeps continuously instead of suspending. Turn
  2119. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  2120. T400CDT. This is off by default since most machines do fine without
  2121. this feature.
  2122. config APM_CPU_IDLE
  2123. depends on CPU_IDLE
  2124. bool "Make CPU Idle calls when idle"
  2125. ---help---
  2126. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  2127. On some machines, this can activate improved power savings, such as
  2128. a slowed CPU clock rate, when the machine is idle. These idle calls
  2129. are made after the idle loop has run for some length of time (e.g.,
  2130. 333 mS). On some machines, this will cause a hang at boot time or
  2131. whenever the CPU becomes idle. (On machines with more than one CPU,
  2132. this option does nothing.)
  2133. config APM_DISPLAY_BLANK
  2134. bool "Enable console blanking using APM"
  2135. ---help---
  2136. Enable console blanking using the APM. Some laptops can use this to
  2137. turn off the LCD backlight when the screen blanker of the Linux
  2138. virtual console blanks the screen. Note that this is only used by
  2139. the virtual console screen blanker, and won't turn off the backlight
  2140. when using the X Window system. This also doesn't have anything to
  2141. do with your VESA-compliant power-saving monitor. Further, this
  2142. option doesn't work for all laptops -- it might not turn off your
  2143. backlight at all, or it might print a lot of errors to the console,
  2144. especially if you are using gpm.
  2145. config APM_ALLOW_INTS
  2146. bool "Allow interrupts during APM BIOS calls"
  2147. ---help---
  2148. Normally we disable external interrupts while we are making calls to
  2149. the APM BIOS as a measure to lessen the effects of a badly behaving
  2150. BIOS implementation. The BIOS should reenable interrupts if it
  2151. needs to. Unfortunately, some BIOSes do not -- especially those in
  2152. many of the newer IBM Thinkpads. If you experience hangs when you
  2153. suspend, try setting this to Y. Otherwise, say N.
  2154. endif # APM
  2155. source "drivers/cpufreq/Kconfig"
  2156. source "drivers/cpuidle/Kconfig"
  2157. source "drivers/idle/Kconfig"
  2158. endmenu
  2159. menu "Bus options (PCI etc.)"
  2160. config PCI
  2161. bool "PCI support"
  2162. default y
  2163. ---help---
  2164. Find out whether you have a PCI motherboard. PCI is the name of a
  2165. bus system, i.e. the way the CPU talks to the other stuff inside
  2166. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  2167. VESA. If you have PCI, say Y, otherwise N.
  2168. choice
  2169. prompt "PCI access mode"
  2170. depends on X86_32 && PCI
  2171. default PCI_GOANY
  2172. ---help---
  2173. On PCI systems, the BIOS can be used to detect the PCI devices and
  2174. determine their configuration. However, some old PCI motherboards
  2175. have BIOS bugs and may crash if this is done. Also, some embedded
  2176. PCI-based systems don't have any BIOS at all. Linux can also try to
  2177. detect the PCI hardware directly without using the BIOS.
  2178. With this option, you can specify how Linux should detect the
  2179. PCI devices. If you choose "BIOS", the BIOS will be used,
  2180. if you choose "Direct", the BIOS won't be used, and if you
  2181. choose "MMConfig", then PCI Express MMCONFIG will be used.
  2182. If you choose "Any", the kernel will try MMCONFIG, then the
  2183. direct access method and falls back to the BIOS if that doesn't
  2184. work. If unsure, go with the default, which is "Any".
  2185. config PCI_GOBIOS
  2186. bool "BIOS"
  2187. config PCI_GOMMCONFIG
  2188. bool "MMConfig"
  2189. config PCI_GODIRECT
  2190. bool "Direct"
  2191. config PCI_GOOLPC
  2192. bool "OLPC XO-1"
  2193. depends on OLPC
  2194. config PCI_GOANY
  2195. bool "Any"
  2196. endchoice
  2197. config PCI_BIOS
  2198. def_bool y
  2199. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  2200. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  2201. config PCI_DIRECT
  2202. def_bool y
  2203. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
  2204. config PCI_MMCONFIG
  2205. bool "Support mmconfig PCI config space access" if X86_64
  2206. default y
  2207. depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
  2208. depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
  2209. config PCI_OLPC
  2210. def_bool y
  2211. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  2212. config PCI_XEN
  2213. def_bool y
  2214. depends on PCI && XEN
  2215. select SWIOTLB_XEN
  2216. config PCI_DOMAINS
  2217. def_bool y
  2218. depends on PCI
  2219. config MMCONF_FAM10H
  2220. def_bool y
  2221. depends on X86_64 && PCI_MMCONFIG && ACPI
  2222. config PCI_CNB20LE_QUIRK
  2223. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  2224. depends on PCI
  2225. help
  2226. Read the PCI windows out of the CNB20LE host bridge. This allows
  2227. PCI hotplug to work on systems with the CNB20LE chipset which do
  2228. not have ACPI.
  2229. There's no public spec for this chipset, and this functionality
  2230. is known to be incomplete.
  2231. You should say N unless you know you need this.
  2232. source "drivers/pci/Kconfig"
  2233. config ISA_BUS
  2234. bool "ISA bus support on modern systems" if EXPERT
  2235. help
  2236. Expose ISA bus device drivers and options available for selection and
  2237. configuration. Enable this option if your target machine has an ISA
  2238. bus. ISA is an older system, displaced by PCI and newer bus
  2239. architectures -- if your target machine is modern, it probably does
  2240. not have an ISA bus.
  2241. If unsure, say N.
  2242. # x86_64 have no ISA slots, but can have ISA-style DMA.
  2243. config ISA_DMA_API
  2244. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  2245. default y
  2246. help
  2247. Enables ISA-style DMA support for devices requiring such controllers.
  2248. If unsure, say Y.
  2249. if X86_32
  2250. config ISA
  2251. bool "ISA support"
  2252. ---help---
  2253. Find out whether you have ISA slots on your motherboard. ISA is the
  2254. name of a bus system, i.e. the way the CPU talks to the other stuff
  2255. inside your box. Other bus systems are PCI, EISA, MicroChannel
  2256. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  2257. newer boards don't support it. If you have ISA, say Y, otherwise N.
  2258. config EISA
  2259. bool "EISA support"
  2260. depends on ISA
  2261. ---help---
  2262. The Extended Industry Standard Architecture (EISA) bus was
  2263. developed as an open alternative to the IBM MicroChannel bus.
  2264. The EISA bus provided some of the features of the IBM MicroChannel
  2265. bus while maintaining backward compatibility with cards made for
  2266. the older ISA bus. The EISA bus saw limited use between 1988 and
  2267. 1995 when it was made obsolete by the PCI bus.
  2268. Say Y here if you are building a kernel for an EISA-based machine.
  2269. Otherwise, say N.
  2270. source "drivers/eisa/Kconfig"
  2271. config SCx200
  2272. tristate "NatSemi SCx200 support"
  2273. ---help---
  2274. This provides basic support for National Semiconductor's
  2275. (now AMD's) Geode processors. The driver probes for the
  2276. PCI-IDs of several on-chip devices, so its a good dependency
  2277. for other scx200_* drivers.
  2278. If compiled as a module, the driver is named scx200.
  2279. config SCx200HR_TIMER
  2280. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  2281. depends on SCx200
  2282. default y
  2283. ---help---
  2284. This driver provides a clocksource built upon the on-chip
  2285. 27MHz high-resolution timer. Its also a workaround for
  2286. NSC Geode SC-1100's buggy TSC, which loses time when the
  2287. processor goes idle (as is done by the scheduler). The
  2288. other workaround is idle=poll boot option.
  2289. config OLPC
  2290. bool "One Laptop Per Child support"
  2291. depends on !X86_PAE
  2292. select GPIOLIB
  2293. select OF
  2294. select OF_PROMTREE
  2295. select IRQ_DOMAIN
  2296. ---help---
  2297. Add support for detecting the unique features of the OLPC
  2298. XO hardware.
  2299. config OLPC_XO1_PM
  2300. bool "OLPC XO-1 Power Management"
  2301. depends on OLPC && MFD_CS5535=y && PM_SLEEP
  2302. ---help---
  2303. Add support for poweroff and suspend of the OLPC XO-1 laptop.
  2304. config OLPC_XO1_RTC
  2305. bool "OLPC XO-1 Real Time Clock"
  2306. depends on OLPC_XO1_PM && RTC_DRV_CMOS
  2307. ---help---
  2308. Add support for the XO-1 real time clock, which can be used as a
  2309. programmable wakeup source.
  2310. config OLPC_XO1_SCI
  2311. bool "OLPC XO-1 SCI extras"
  2312. depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
  2313. depends on INPUT=y
  2314. select POWER_SUPPLY
  2315. ---help---
  2316. Add support for SCI-based features of the OLPC XO-1 laptop:
  2317. - EC-driven system wakeups
  2318. - Power button
  2319. - Ebook switch
  2320. - Lid switch
  2321. - AC adapter status updates
  2322. - Battery status updates
  2323. config OLPC_XO15_SCI
  2324. bool "OLPC XO-1.5 SCI extras"
  2325. depends on OLPC && ACPI
  2326. select POWER_SUPPLY
  2327. ---help---
  2328. Add support for SCI-based features of the OLPC XO-1.5 laptop:
  2329. - EC-driven system wakeups
  2330. - AC adapter status updates
  2331. - Battery status updates
  2332. config ALIX
  2333. bool "PCEngines ALIX System Support (LED setup)"
  2334. select GPIOLIB
  2335. ---help---
  2336. This option enables system support for the PCEngines ALIX.
  2337. At present this just sets up LEDs for GPIO control on
  2338. ALIX2/3/6 boards. However, other system specific setup should
  2339. get added here.
  2340. Note: You must still enable the drivers for GPIO and LED support
  2341. (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
  2342. Note: You have to set alix.force=1 for boards with Award BIOS.
  2343. config NET5501
  2344. bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
  2345. select GPIOLIB
  2346. ---help---
  2347. This option enables system support for the Soekris Engineering net5501.
  2348. config GEOS
  2349. bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
  2350. select GPIOLIB
  2351. depends on DMI
  2352. ---help---
  2353. This option enables system support for the Traverse Technologies GEOS.
  2354. config TS5500
  2355. bool "Technologic Systems TS-5500 platform support"
  2356. depends on MELAN
  2357. select CHECK_SIGNATURE
  2358. select NEW_LEDS
  2359. select LEDS_CLASS
  2360. ---help---
  2361. This option enables system support for the Technologic Systems TS-5500.
  2362. endif # X86_32
  2363. config AMD_NB
  2364. def_bool y
  2365. depends on CPU_SUP_AMD && PCI
  2366. source "drivers/pcmcia/Kconfig"
  2367. config RAPIDIO
  2368. tristate "RapidIO support"
  2369. depends on PCI
  2370. help
  2371. If enabled this option will include drivers and the core
  2372. infrastructure code to support RapidIO interconnect devices.
  2373. source "drivers/rapidio/Kconfig"
  2374. config X86_SYSFB
  2375. bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
  2376. help
  2377. Firmwares often provide initial graphics framebuffers so the BIOS,
  2378. bootloader or kernel can show basic video-output during boot for
  2379. user-guidance and debugging. Historically, x86 used the VESA BIOS
  2380. Extensions and EFI-framebuffers for this, which are mostly limited
  2381. to x86.
  2382. This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
  2383. framebuffers so the new generic system-framebuffer drivers can be
  2384. used on x86. If the framebuffer is not compatible with the generic
  2385. modes, it is advertised as fallback platform framebuffer so legacy
  2386. drivers like efifb, vesafb and uvesafb can pick it up.
  2387. If this option is not selected, all system framebuffers are always
  2388. marked as fallback platform framebuffers as usual.
  2389. Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
  2390. not be able to pick up generic system framebuffers if this option
  2391. is selected. You are highly encouraged to enable simplefb as
  2392. replacement if you select this option. simplefb can correctly deal
  2393. with generic system framebuffers. But you should still keep vesafb
  2394. and others enabled as fallback if a system framebuffer is
  2395. incompatible with simplefb.
  2396. If unsure, say Y.
  2397. endmenu
  2398. menu "Binary Emulations"
  2399. config IA32_EMULATION
  2400. bool "IA32 Emulation"
  2401. depends on X86_64
  2402. select ARCH_WANT_OLD_COMPAT_IPC
  2403. select BINFMT_ELF
  2404. select COMPAT_BINFMT_ELF
  2405. select COMPAT_OLD_SIGACTION
  2406. ---help---
  2407. Include code to run legacy 32-bit programs under a
  2408. 64-bit kernel. You should likely turn this on, unless you're
  2409. 100% sure that you don't have any 32-bit programs left.
  2410. config IA32_AOUT
  2411. tristate "IA32 a.out support"
  2412. depends on IA32_EMULATION
  2413. ---help---
  2414. Support old a.out binaries in the 32bit emulation.
  2415. config X86_X32
  2416. bool "x32 ABI for 64-bit mode"
  2417. depends on X86_64
  2418. ---help---
  2419. Include code to run binaries for the x32 native 32-bit ABI
  2420. for 64-bit processors. An x32 process gets access to the
  2421. full 64-bit register file and wide data path while leaving
  2422. pointers at 32 bits for smaller memory footprint.
  2423. You will need a recent binutils (2.22 or later) with
  2424. elf32_x86_64 support enabled to compile a kernel with this
  2425. option set.
  2426. config COMPAT_32
  2427. def_bool y
  2428. depends on IA32_EMULATION || X86_32
  2429. select HAVE_UID16
  2430. select OLD_SIGSUSPEND3
  2431. config COMPAT
  2432. def_bool y
  2433. depends on IA32_EMULATION || X86_X32
  2434. if COMPAT
  2435. config COMPAT_FOR_U64_ALIGNMENT
  2436. def_bool y
  2437. config SYSVIPC_COMPAT
  2438. def_bool y
  2439. depends on SYSVIPC
  2440. endif
  2441. endmenu
  2442. config HAVE_ATOMIC_IOMAP
  2443. def_bool y
  2444. depends on X86_32
  2445. config X86_DEV_DMA_OPS
  2446. bool
  2447. depends on X86_64 || STA2X11
  2448. config X86_DMA_REMAP
  2449. bool
  2450. depends on STA2X11
  2451. config HAVE_GENERIC_GUP
  2452. def_bool y
  2453. source "drivers/firmware/Kconfig"
  2454. source "arch/x86/kvm/Kconfig"