Kconfig 63 KB

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  1. # x86 configuration
  2. mainmenu "Linux Kernel Configuration for x86"
  3. # Select 32 or 64 bit
  4. config 64BIT
  5. bool "64-bit kernel" if ARCH = "x86"
  6. default ARCH = "x86_64"
  7. help
  8. Say yes to build a 64-bit kernel - formerly known as x86_64
  9. Say no to build a 32-bit kernel - formerly known as i386
  10. config X86_32
  11. def_bool !64BIT
  12. config X86_64
  13. def_bool 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select HAVE_AOUT if X86_32
  18. select HAVE_READQ
  19. select HAVE_WRITEQ
  20. select HAVE_UNSTABLE_SCHED_CLOCK
  21. select HAVE_IDE
  22. select HAVE_OPROFILE
  23. select HAVE_IOREMAP_PROT
  24. select HAVE_KPROBES
  25. select ARCH_WANT_OPTIONAL_GPIOLIB
  26. select ARCH_WANT_FRAME_POINTERS
  27. select HAVE_KRETPROBES
  28. select HAVE_FTRACE_MCOUNT_RECORD
  29. select HAVE_DYNAMIC_FTRACE
  30. select HAVE_FUNCTION_TRACER
  31. select HAVE_FUNCTION_GRAPH_TRACER
  32. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  33. select HAVE_KVM
  34. select HAVE_ARCH_KGDB
  35. select HAVE_ARCH_TRACEHOOK
  36. select HAVE_GENERIC_DMA_COHERENT if X86_32
  37. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  38. select USER_STACKTRACE_SUPPORT
  39. config ARCH_DEFCONFIG
  40. string
  41. default "arch/x86/configs/i386_defconfig" if X86_32
  42. default "arch/x86/configs/x86_64_defconfig" if X86_64
  43. config GENERIC_TIME
  44. def_bool y
  45. config GENERIC_CMOS_UPDATE
  46. def_bool y
  47. config CLOCKSOURCE_WATCHDOG
  48. def_bool y
  49. config GENERIC_CLOCKEVENTS
  50. def_bool y
  51. config GENERIC_CLOCKEVENTS_BROADCAST
  52. def_bool y
  53. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  54. config LOCKDEP_SUPPORT
  55. def_bool y
  56. config STACKTRACE_SUPPORT
  57. def_bool y
  58. config HAVE_LATENCYTOP_SUPPORT
  59. def_bool y
  60. config FAST_CMPXCHG_LOCAL
  61. bool
  62. default y
  63. config MMU
  64. def_bool y
  65. config ZONE_DMA
  66. def_bool y
  67. config SBUS
  68. bool
  69. config GENERIC_ISA_DMA
  70. def_bool y
  71. config GENERIC_IOMAP
  72. def_bool y
  73. config GENERIC_BUG
  74. def_bool y
  75. depends on BUG
  76. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  77. config GENERIC_BUG_RELATIVE_POINTERS
  78. bool
  79. config GENERIC_HWEIGHT
  80. def_bool y
  81. config GENERIC_GPIO
  82. bool
  83. config ARCH_MAY_HAVE_PC_FDC
  84. def_bool y
  85. config RWSEM_GENERIC_SPINLOCK
  86. def_bool !X86_XADD
  87. config RWSEM_XCHGADD_ALGORITHM
  88. def_bool X86_XADD
  89. config ARCH_HAS_CPU_IDLE_WAIT
  90. def_bool y
  91. config GENERIC_CALIBRATE_DELAY
  92. def_bool y
  93. config GENERIC_TIME_VSYSCALL
  94. bool
  95. default X86_64
  96. config ARCH_HAS_CPU_RELAX
  97. def_bool y
  98. config ARCH_HAS_DEFAULT_IDLE
  99. def_bool y
  100. config ARCH_HAS_CACHE_LINE_SIZE
  101. def_bool y
  102. config HAVE_SETUP_PER_CPU_AREA
  103. def_bool y
  104. config HAVE_CPUMASK_OF_CPU_MAP
  105. def_bool X86_64_SMP
  106. config ARCH_HIBERNATION_POSSIBLE
  107. def_bool y
  108. depends on !SMP
  109. config ARCH_SUSPEND_POSSIBLE
  110. def_bool y
  111. config ZONE_DMA32
  112. bool
  113. default X86_64
  114. config ARCH_POPULATES_NODE_MAP
  115. def_bool y
  116. config AUDIT_ARCH
  117. bool
  118. default X86_64
  119. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  120. def_bool y
  121. # Use the generic interrupt handling code in kernel/irq/:
  122. config GENERIC_HARDIRQS
  123. bool
  124. default y
  125. config GENERIC_IRQ_PROBE
  126. bool
  127. default y
  128. config GENERIC_PENDING_IRQ
  129. bool
  130. depends on GENERIC_HARDIRQS && SMP
  131. default y
  132. config USE_GENERIC_SMP_HELPERS
  133. def_bool y
  134. depends on SMP
  135. config X86_32_SMP
  136. def_bool y
  137. depends on X86_32 && SMP
  138. config X86_64_SMP
  139. def_bool y
  140. depends on X86_64 && SMP
  141. config X86_HT
  142. bool
  143. depends on SMP
  144. default y
  145. config X86_TRAMPOLINE
  146. bool
  147. depends on SMP || (64BIT && ACPI_SLEEP)
  148. default y
  149. config KTIME_SCALAR
  150. def_bool X86_32
  151. source "init/Kconfig"
  152. source "kernel/Kconfig.freezer"
  153. menu "Processor type and features"
  154. source "kernel/time/Kconfig"
  155. config SMP
  156. bool "Symmetric multi-processing support"
  157. ---help---
  158. This enables support for systems with more than one CPU. If you have
  159. a system with only one CPU, like most personal computers, say N. If
  160. you have a system with more than one CPU, say Y.
  161. If you say N here, the kernel will run on single and multiprocessor
  162. machines, but will use only one CPU of a multiprocessor machine. If
  163. you say Y here, the kernel will run on many, but not all,
  164. singleprocessor machines. On a singleprocessor machine, the kernel
  165. will run faster if you say N here.
  166. Note that if you say Y here and choose architecture "586" or
  167. "Pentium" under "Processor family", the kernel will not work on 486
  168. architectures. Similarly, multiprocessor kernels for the "PPro"
  169. architecture may not work on all Pentium based boards.
  170. People using multiprocessor machines who say Y here should also say
  171. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  172. Management" code will be disabled if you say Y here.
  173. See also <file:Documentation/i386/IO-APIC.txt>,
  174. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  175. <http://www.tldp.org/docs.html#howto>.
  176. If you don't know what to do here, say N.
  177. config SPARSE_IRQ
  178. bool "Support sparse irq numbering"
  179. depends on PCI_MSI || HT_IRQ
  180. help
  181. This enables support for sparse irqs. This is useful for distro
  182. kernels that want to define a high CONFIG_NR_CPUS value but still
  183. want to have low kernel memory footprint on smaller machines.
  184. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  185. out the irq_desc[] array in a more NUMA-friendly way. )
  186. If you don't know what to do here, say N.
  187. config NUMA_MIGRATE_IRQ_DESC
  188. bool "Move irq desc when changing irq smp_affinity"
  189. depends on SPARSE_IRQ && NUMA
  190. default n
  191. help
  192. This enables moving irq_desc to cpu/node that irq will use handled.
  193. If you don't know what to do here, say N.
  194. config X86_MPPARSE
  195. bool "Enable MPS table" if ACPI
  196. default y
  197. depends on X86_LOCAL_APIC
  198. help
  199. For old smp systems that do not have proper acpi support. Newer systems
  200. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  201. choice
  202. prompt "Subarchitecture Type"
  203. default X86_PC
  204. config X86_PC
  205. bool "PC-compatible"
  206. help
  207. Choose this option if your computer is a standard PC or compatible.
  208. config X86_ELAN
  209. bool "AMD Elan"
  210. depends on X86_32
  211. help
  212. Select this for an AMD Elan processor.
  213. Do not use this option for K6/Athlon/Opteron processors!
  214. If unsure, choose "PC-compatible" instead.
  215. config X86_VOYAGER
  216. bool "Voyager (NCR)"
  217. depends on X86_32 && SMP && !PCI && BROKEN
  218. help
  219. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  220. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  221. *** WARNING ***
  222. If you do not specifically know you have a Voyager based machine,
  223. say N here, otherwise the kernel you build will not be bootable.
  224. config X86_GENERICARCH
  225. bool "Generic architecture"
  226. depends on X86_32
  227. help
  228. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  229. subarchitectures. It is intended for a generic binary kernel.
  230. if you select them all, kernel will probe it one by one. and will
  231. fallback to default.
  232. if X86_GENERICARCH
  233. config X86_NUMAQ
  234. bool "NUMAQ (IBM/Sequent)"
  235. depends on SMP && X86_32 && PCI && X86_MPPARSE
  236. select NUMA
  237. help
  238. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  239. NUMA multiquad box. This changes the way that processors are
  240. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  241. of Flat Logical. You will need a new lynxer.elf file to flash your
  242. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  243. config X86_SUMMIT
  244. bool "Summit/EXA (IBM x440)"
  245. depends on X86_32 && SMP
  246. help
  247. This option is needed for IBM systems that use the Summit/EXA chipset.
  248. In particular, it is needed for the x440.
  249. config X86_ES7000
  250. bool "Support for Unisys ES7000 IA32 series"
  251. depends on X86_32 && SMP
  252. help
  253. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  254. supposed to run on an IA32-based Unisys ES7000 system.
  255. config X86_BIGSMP
  256. bool "Support for big SMP systems with more than 8 CPUs"
  257. depends on X86_32 && SMP
  258. help
  259. This option is needed for the systems that have more than 8 CPUs
  260. and if the system is not of any sub-arch type above.
  261. endif
  262. config X86_VSMP
  263. bool "Support for ScaleMP vSMP"
  264. select PARAVIRT
  265. depends on X86_64 && PCI
  266. help
  267. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  268. supposed to run on these EM64T-based machines. Only choose this option
  269. if you have one of these machines.
  270. endchoice
  271. config X86_VISWS
  272. bool "SGI 320/540 (Visual Workstation)"
  273. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  274. help
  275. The SGI Visual Workstation series is an IA32-based workstation
  276. based on SGI systems chips with some legacy PC hardware attached.
  277. Say Y here to create a kernel to run on the SGI 320 or 540.
  278. A kernel compiled for the Visual Workstation will run on general
  279. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  280. config X86_RDC321X
  281. bool "RDC R-321x SoC"
  282. depends on X86_32
  283. select M486
  284. select X86_REBOOTFIXUPS
  285. help
  286. This option is needed for RDC R-321x system-on-chip, also known
  287. as R-8610-(G).
  288. If you don't have one of these chips, you should say N here.
  289. config X86_UV
  290. bool "SGI Ultraviolet"
  291. depends on X86_64
  292. help
  293. This option is needed in order to support SGI Ultraviolet systems.
  294. If you don't have one of these, you should say N here.
  295. config SCHED_OMIT_FRAME_POINTER
  296. def_bool y
  297. prompt "Single-depth WCHAN output"
  298. depends on X86
  299. help
  300. Calculate simpler /proc/<PID>/wchan values. If this option
  301. is disabled then wchan values will recurse back to the
  302. caller function. This provides more accurate wchan values,
  303. at the expense of slightly more scheduling overhead.
  304. If in doubt, say "Y".
  305. menuconfig PARAVIRT_GUEST
  306. bool "Paravirtualized guest support"
  307. help
  308. Say Y here to get to see options related to running Linux under
  309. various hypervisors. This option alone does not add any kernel code.
  310. If you say N, all options in this submenu will be skipped and disabled.
  311. if PARAVIRT_GUEST
  312. source "arch/x86/xen/Kconfig"
  313. config VMI
  314. bool "VMI Guest support"
  315. select PARAVIRT
  316. depends on X86_32
  317. help
  318. VMI provides a paravirtualized interface to the VMware ESX server
  319. (it could be used by other hypervisors in theory too, but is not
  320. at the moment), by linking the kernel to a GPL-ed ROM module
  321. provided by the hypervisor.
  322. config KVM_CLOCK
  323. bool "KVM paravirtualized clock"
  324. select PARAVIRT
  325. select PARAVIRT_CLOCK
  326. help
  327. Turning on this option will allow you to run a paravirtualized clock
  328. when running over the KVM hypervisor. Instead of relying on a PIT
  329. (or probably other) emulation by the underlying device model, the host
  330. provides the guest with timing infrastructure such as time of day, and
  331. system time
  332. config KVM_GUEST
  333. bool "KVM Guest support"
  334. select PARAVIRT
  335. help
  336. This option enables various optimizations for running under the KVM
  337. hypervisor.
  338. source "arch/x86/lguest/Kconfig"
  339. config PARAVIRT
  340. bool "Enable paravirtualization code"
  341. help
  342. This changes the kernel so it can modify itself when it is run
  343. under a hypervisor, potentially improving performance significantly
  344. over full virtualization. However, when run without a hypervisor
  345. the kernel is theoretically slower and slightly larger.
  346. config PARAVIRT_CLOCK
  347. bool
  348. default n
  349. endif
  350. config PARAVIRT_DEBUG
  351. bool "paravirt-ops debugging"
  352. depends on PARAVIRT && DEBUG_KERNEL
  353. help
  354. Enable to debug paravirt_ops internals. Specifically, BUG if
  355. a paravirt_op is missing when it is called.
  356. config MEMTEST
  357. bool "Memtest"
  358. help
  359. This option adds a kernel parameter 'memtest', which allows memtest
  360. to be set.
  361. memtest=0, mean disabled; -- default
  362. memtest=1, mean do 1 test pattern;
  363. ...
  364. memtest=4, mean do 4 test patterns.
  365. If you are unsure how to answer this question, answer N.
  366. config X86_SUMMIT_NUMA
  367. def_bool y
  368. depends on X86_32 && NUMA && X86_GENERICARCH
  369. config X86_CYCLONE_TIMER
  370. def_bool y
  371. depends on X86_GENERICARCH
  372. source "arch/x86/Kconfig.cpu"
  373. config HPET_TIMER
  374. def_bool X86_64
  375. prompt "HPET Timer Support" if X86_32
  376. help
  377. Use the IA-PC HPET (High Precision Event Timer) to manage
  378. time in preference to the PIT and RTC, if a HPET is
  379. present.
  380. HPET is the next generation timer replacing legacy 8254s.
  381. The HPET provides a stable time base on SMP
  382. systems, unlike the TSC, but it is more expensive to access,
  383. as it is off-chip. You can find the HPET spec at
  384. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  385. You can safely choose Y here. However, HPET will only be
  386. activated if the platform and the BIOS support this feature.
  387. Otherwise the 8254 will be used for timing services.
  388. Choose N to continue using the legacy 8254 timer.
  389. config HPET_EMULATE_RTC
  390. def_bool y
  391. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  392. # Mark as embedded because too many people got it wrong.
  393. # The code disables itself when not needed.
  394. config DMI
  395. default y
  396. bool "Enable DMI scanning" if EMBEDDED
  397. help
  398. Enabled scanning of DMI to identify machine quirks. Say Y
  399. here unless you have verified that your setup is not
  400. affected by entries in the DMI blacklist. Required by PNP
  401. BIOS code.
  402. config GART_IOMMU
  403. bool "GART IOMMU support" if EMBEDDED
  404. default y
  405. select SWIOTLB
  406. select AGP
  407. depends on X86_64 && PCI
  408. help
  409. Support for full DMA access of devices with 32bit memory access only
  410. on systems with more than 3GB. This is usually needed for USB,
  411. sound, many IDE/SATA chipsets and some other devices.
  412. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  413. based hardware IOMMU and a software bounce buffer based IOMMU used
  414. on Intel systems and as fallback.
  415. The code is only active when needed (enough memory and limited
  416. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  417. too.
  418. config CALGARY_IOMMU
  419. bool "IBM Calgary IOMMU support"
  420. select SWIOTLB
  421. depends on X86_64 && PCI && EXPERIMENTAL
  422. help
  423. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  424. systems. Needed to run systems with more than 3GB of memory
  425. properly with 32-bit PCI devices that do not support DAC
  426. (Double Address Cycle). Calgary also supports bus level
  427. isolation, where all DMAs pass through the IOMMU. This
  428. prevents them from going anywhere except their intended
  429. destination. This catches hard-to-find kernel bugs and
  430. mis-behaving drivers and devices that do not use the DMA-API
  431. properly to set up their DMA buffers. The IOMMU can be
  432. turned off at boot time with the iommu=off parameter.
  433. Normally the kernel will make the right choice by itself.
  434. If unsure, say Y.
  435. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  436. def_bool y
  437. prompt "Should Calgary be enabled by default?"
  438. depends on CALGARY_IOMMU
  439. help
  440. Should Calgary be enabled by default? if you choose 'y', Calgary
  441. will be used (if it exists). If you choose 'n', Calgary will not be
  442. used even if it exists. If you choose 'n' and would like to use
  443. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  444. If unsure, say Y.
  445. config AMD_IOMMU
  446. bool "AMD IOMMU support"
  447. select SWIOTLB
  448. select PCI_MSI
  449. depends on X86_64 && PCI && ACPI
  450. help
  451. With this option you can enable support for AMD IOMMU hardware in
  452. your system. An IOMMU is a hardware component which provides
  453. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  454. can isolate the the DMA memory of different devices and protect the
  455. system from misbehaving device drivers or hardware.
  456. You can find out if your system has an AMD IOMMU if you look into
  457. your BIOS for an option to enable it or if you have an IVRS ACPI
  458. table.
  459. config AMD_IOMMU_STATS
  460. bool "Export AMD IOMMU statistics to debugfs"
  461. depends on AMD_IOMMU
  462. select DEBUG_FS
  463. help
  464. This option enables code in the AMD IOMMU driver to collect various
  465. statistics about whats happening in the driver and exports that
  466. information to userspace via debugfs.
  467. If unsure, say N.
  468. # need this always selected by IOMMU for the VIA workaround
  469. config SWIOTLB
  470. def_bool y if X86_64
  471. help
  472. Support for software bounce buffers used on x86-64 systems
  473. which don't have a hardware IOMMU (e.g. the current generation
  474. of Intel's x86-64 CPUs). Using this PCI devices which can only
  475. access 32-bits of memory can be used on systems with more than
  476. 3 GB of memory. If unsure, say Y.
  477. config IOMMU_HELPER
  478. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  479. config IOMMU_API
  480. def_bool (AMD_IOMMU || DMAR)
  481. config MAXSMP
  482. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  483. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  484. select CPUMASK_OFFSTACK
  485. default n
  486. help
  487. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  488. If unsure, say N.
  489. config NR_CPUS
  490. int "Maximum number of CPUs" if SMP && !MAXSMP
  491. range 2 512 if SMP && !MAXSMP
  492. default "1" if !SMP
  493. default "4096" if MAXSMP
  494. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  495. default "8" if SMP
  496. help
  497. This allows you to specify the maximum number of CPUs which this
  498. kernel will support. The maximum supported value is 512 and the
  499. minimum value which makes sense is 2.
  500. This is purely to save memory - each supported CPU adds
  501. approximately eight kilobytes to the kernel image.
  502. config SCHED_SMT
  503. bool "SMT (Hyperthreading) scheduler support"
  504. depends on X86_HT
  505. help
  506. SMT scheduler support improves the CPU scheduler's decision making
  507. when dealing with Intel Pentium 4 chips with HyperThreading at a
  508. cost of slightly increased overhead in some places. If unsure say
  509. N here.
  510. config SCHED_MC
  511. def_bool y
  512. prompt "Multi-core scheduler support"
  513. depends on X86_HT
  514. help
  515. Multi-core scheduler support improves the CPU scheduler's decision
  516. making when dealing with multi-core CPU chips at a cost of slightly
  517. increased overhead in some places. If unsure say N here.
  518. source "kernel/Kconfig.preempt"
  519. config X86_UP_APIC
  520. bool "Local APIC support on uniprocessors"
  521. depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
  522. help
  523. A local APIC (Advanced Programmable Interrupt Controller) is an
  524. integrated interrupt controller in the CPU. If you have a single-CPU
  525. system which has a processor with a local APIC, you can say Y here to
  526. enable and use it. If you say Y here even though your machine doesn't
  527. have a local APIC, then the kernel will still run with no slowdown at
  528. all. The local APIC supports CPU-generated self-interrupts (timer,
  529. performance counters), and the NMI watchdog which detects hard
  530. lockups.
  531. config X86_UP_IOAPIC
  532. bool "IO-APIC support on uniprocessors"
  533. depends on X86_UP_APIC
  534. help
  535. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  536. SMP-capable replacement for PC-style interrupt controllers. Most
  537. SMP systems and many recent uniprocessor systems have one.
  538. If you have a single-CPU system with an IO-APIC, you can say Y here
  539. to use it. If you say Y here even though your machine doesn't have
  540. an IO-APIC, then the kernel will still run with no slowdown at all.
  541. config X86_LOCAL_APIC
  542. def_bool y
  543. depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
  544. config X86_IO_APIC
  545. def_bool y
  546. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
  547. config X86_VISWS_APIC
  548. def_bool y
  549. depends on X86_32 && X86_VISWS
  550. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  551. bool "Reroute for broken boot IRQs"
  552. default n
  553. depends on X86_IO_APIC
  554. help
  555. This option enables a workaround that fixes a source of
  556. spurious interrupts. This is recommended when threaded
  557. interrupt handling is used on systems where the generation of
  558. superfluous "boot interrupts" cannot be disabled.
  559. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  560. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  561. kernel does during interrupt handling). On chipsets where this
  562. boot IRQ generation cannot be disabled, this workaround keeps
  563. the original IRQ line masked so that only the equivalent "boot
  564. IRQ" is delivered to the CPUs. The workaround also tells the
  565. kernel to set up the IRQ handler on the boot IRQ line. In this
  566. way only one interrupt is delivered to the kernel. Otherwise
  567. the spurious second interrupt may cause the kernel to bring
  568. down (vital) interrupt lines.
  569. Only affects "broken" chipsets. Interrupt sharing may be
  570. increased on these systems.
  571. config X86_MCE
  572. bool "Machine Check Exception"
  573. depends on !X86_VOYAGER
  574. ---help---
  575. Machine Check Exception support allows the processor to notify the
  576. kernel if it detects a problem (e.g. overheating, component failure).
  577. The action the kernel takes depends on the severity of the problem,
  578. ranging from a warning message on the console, to halting the machine.
  579. Your processor must be a Pentium or newer to support this - check the
  580. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  581. have a design flaw which leads to false MCE events - hence MCE is
  582. disabled on all P5 processors, unless explicitly enabled with "mce"
  583. as a boot argument. Similarly, if MCE is built in and creates a
  584. problem on some new non-standard machine, you can boot with "nomce"
  585. to disable it. MCE support simply ignores non-MCE processors like
  586. the 386 and 486, so nearly everyone can say Y here.
  587. config X86_MCE_INTEL
  588. def_bool y
  589. prompt "Intel MCE features"
  590. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  591. help
  592. Additional support for intel specific MCE features such as
  593. the thermal monitor.
  594. config X86_MCE_AMD
  595. def_bool y
  596. prompt "AMD MCE features"
  597. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  598. help
  599. Additional support for AMD specific MCE features such as
  600. the DRAM Error Threshold.
  601. config X86_MCE_NONFATAL
  602. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  603. depends on X86_32 && X86_MCE
  604. help
  605. Enabling this feature starts a timer that triggers every 5 seconds which
  606. will look at the machine check registers to see if anything happened.
  607. Non-fatal problems automatically get corrected (but still logged).
  608. Disable this if you don't want to see these messages.
  609. Seeing the messages this option prints out may be indicative of dying
  610. or out-of-spec (ie, overclocked) hardware.
  611. This option only does something on certain CPUs.
  612. (AMD Athlon/Duron and Intel Pentium 4)
  613. config X86_MCE_P4THERMAL
  614. bool "check for P4 thermal throttling interrupt."
  615. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
  616. help
  617. Enabling this feature will cause a message to be printed when the P4
  618. enters thermal throttling.
  619. config VM86
  620. bool "Enable VM86 support" if EMBEDDED
  621. default y
  622. depends on X86_32
  623. help
  624. This option is required by programs like DOSEMU to run 16-bit legacy
  625. code on X86 processors. It also may be needed by software like
  626. XFree86 to initialize some video cards via BIOS. Disabling this
  627. option saves about 6k.
  628. config TOSHIBA
  629. tristate "Toshiba Laptop support"
  630. depends on X86_32
  631. ---help---
  632. This adds a driver to safely access the System Management Mode of
  633. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  634. not work on models with a Phoenix BIOS. The System Management Mode
  635. is used to set the BIOS and power saving options on Toshiba portables.
  636. For information on utilities to make use of this driver see the
  637. Toshiba Linux utilities web site at:
  638. <http://www.buzzard.org.uk/toshiba/>.
  639. Say Y if you intend to run this kernel on a Toshiba portable.
  640. Say N otherwise.
  641. config I8K
  642. tristate "Dell laptop support"
  643. ---help---
  644. This adds a driver to safely access the System Management Mode
  645. of the CPU on the Dell Inspiron 8000. The System Management Mode
  646. is used to read cpu temperature and cooling fan status and to
  647. control the fans on the I8K portables.
  648. This driver has been tested only on the Inspiron 8000 but it may
  649. also work with other Dell laptops. You can force loading on other
  650. models by passing the parameter `force=1' to the module. Use at
  651. your own risk.
  652. For information on utilities to make use of this driver see the
  653. I8K Linux utilities web site at:
  654. <http://people.debian.org/~dz/i8k/>
  655. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  656. Say N otherwise.
  657. config X86_REBOOTFIXUPS
  658. bool "Enable X86 board specific fixups for reboot"
  659. depends on X86_32
  660. ---help---
  661. This enables chipset and/or board specific fixups to be done
  662. in order to get reboot to work correctly. This is only needed on
  663. some combinations of hardware and BIOS. The symptom, for which
  664. this config is intended, is when reboot ends with a stalled/hung
  665. system.
  666. Currently, the only fixup is for the Geode machines using
  667. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  668. Say Y if you want to enable the fixup. Currently, it's safe to
  669. enable this option even if you don't need it.
  670. Say N otherwise.
  671. config MICROCODE
  672. tristate "/dev/cpu/microcode - microcode support"
  673. select FW_LOADER
  674. ---help---
  675. If you say Y here, you will be able to update the microcode on
  676. certain Intel and AMD processors. The Intel support is for the
  677. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  678. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  679. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  680. You will obviously need the actual microcode binary data itself
  681. which is not shipped with the Linux kernel.
  682. This option selects the general module only, you need to select
  683. at least one vendor specific module as well.
  684. To compile this driver as a module, choose M here: the
  685. module will be called microcode.
  686. config MICROCODE_INTEL
  687. bool "Intel microcode patch loading support"
  688. depends on MICROCODE
  689. default MICROCODE
  690. select FW_LOADER
  691. --help---
  692. This options enables microcode patch loading support for Intel
  693. processors.
  694. For latest news and information on obtaining all the required
  695. Intel ingredients for this driver, check:
  696. <http://www.urbanmyth.org/microcode/>.
  697. config MICROCODE_AMD
  698. bool "AMD microcode patch loading support"
  699. depends on MICROCODE
  700. select FW_LOADER
  701. --help---
  702. If you select this option, microcode patch loading support for AMD
  703. processors will be enabled.
  704. config MICROCODE_OLD_INTERFACE
  705. def_bool y
  706. depends on MICROCODE
  707. config X86_MSR
  708. tristate "/dev/cpu/*/msr - Model-specific register support"
  709. help
  710. This device gives privileged processes access to the x86
  711. Model-Specific Registers (MSRs). It is a character device with
  712. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  713. MSR accesses are directed to a specific CPU on multi-processor
  714. systems.
  715. config X86_CPUID
  716. tristate "/dev/cpu/*/cpuid - CPU information support"
  717. help
  718. This device gives processes access to the x86 CPUID instruction to
  719. be executed on a specific processor. It is a character device
  720. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  721. /dev/cpu/31/cpuid.
  722. choice
  723. prompt "High Memory Support"
  724. default HIGHMEM4G if !X86_NUMAQ
  725. default HIGHMEM64G if X86_NUMAQ
  726. depends on X86_32
  727. config NOHIGHMEM
  728. bool "off"
  729. depends on !X86_NUMAQ
  730. ---help---
  731. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  732. However, the address space of 32-bit x86 processors is only 4
  733. Gigabytes large. That means that, if you have a large amount of
  734. physical memory, not all of it can be "permanently mapped" by the
  735. kernel. The physical memory that's not permanently mapped is called
  736. "high memory".
  737. If you are compiling a kernel which will never run on a machine with
  738. more than 1 Gigabyte total physical RAM, answer "off" here (default
  739. choice and suitable for most users). This will result in a "3GB/1GB"
  740. split: 3GB are mapped so that each process sees a 3GB virtual memory
  741. space and the remaining part of the 4GB virtual memory space is used
  742. by the kernel to permanently map as much physical memory as
  743. possible.
  744. If the machine has between 1 and 4 Gigabytes physical RAM, then
  745. answer "4GB" here.
  746. If more than 4 Gigabytes is used then answer "64GB" here. This
  747. selection turns Intel PAE (Physical Address Extension) mode on.
  748. PAE implements 3-level paging on IA32 processors. PAE is fully
  749. supported by Linux, PAE mode is implemented on all recent Intel
  750. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  751. then the kernel will not boot on CPUs that don't support PAE!
  752. The actual amount of total physical memory will either be
  753. auto detected or can be forced by using a kernel command line option
  754. such as "mem=256M". (Try "man bootparam" or see the documentation of
  755. your boot loader (lilo or loadlin) about how to pass options to the
  756. kernel at boot time.)
  757. If unsure, say "off".
  758. config HIGHMEM4G
  759. bool "4GB"
  760. depends on !X86_NUMAQ
  761. help
  762. Select this if you have a 32-bit processor and between 1 and 4
  763. gigabytes of physical RAM.
  764. config HIGHMEM64G
  765. bool "64GB"
  766. depends on !M386 && !M486
  767. select X86_PAE
  768. help
  769. Select this if you have a 32-bit processor and more than 4
  770. gigabytes of physical RAM.
  771. endchoice
  772. choice
  773. depends on EXPERIMENTAL
  774. prompt "Memory split" if EMBEDDED
  775. default VMSPLIT_3G
  776. depends on X86_32
  777. help
  778. Select the desired split between kernel and user memory.
  779. If the address range available to the kernel is less than the
  780. physical memory installed, the remaining memory will be available
  781. as "high memory". Accessing high memory is a little more costly
  782. than low memory, as it needs to be mapped into the kernel first.
  783. Note that increasing the kernel address space limits the range
  784. available to user programs, making the address space there
  785. tighter. Selecting anything other than the default 3G/1G split
  786. will also likely make your kernel incompatible with binary-only
  787. kernel modules.
  788. If you are not absolutely sure what you are doing, leave this
  789. option alone!
  790. config VMSPLIT_3G
  791. bool "3G/1G user/kernel split"
  792. config VMSPLIT_3G_OPT
  793. depends on !X86_PAE
  794. bool "3G/1G user/kernel split (for full 1G low memory)"
  795. config VMSPLIT_2G
  796. bool "2G/2G user/kernel split"
  797. config VMSPLIT_2G_OPT
  798. depends on !X86_PAE
  799. bool "2G/2G user/kernel split (for full 2G low memory)"
  800. config VMSPLIT_1G
  801. bool "1G/3G user/kernel split"
  802. endchoice
  803. config PAGE_OFFSET
  804. hex
  805. default 0xB0000000 if VMSPLIT_3G_OPT
  806. default 0x80000000 if VMSPLIT_2G
  807. default 0x78000000 if VMSPLIT_2G_OPT
  808. default 0x40000000 if VMSPLIT_1G
  809. default 0xC0000000
  810. depends on X86_32
  811. config HIGHMEM
  812. def_bool y
  813. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  814. config X86_PAE
  815. bool "PAE (Physical Address Extension) Support"
  816. depends on X86_32 && !HIGHMEM4G
  817. help
  818. PAE is required for NX support, and furthermore enables
  819. larger swapspace support for non-overcommit purposes. It
  820. has the cost of more pagetable lookup overhead, and also
  821. consumes more pagetable space per process.
  822. config ARCH_PHYS_ADDR_T_64BIT
  823. def_bool X86_64 || X86_PAE
  824. config DIRECT_GBPAGES
  825. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  826. default y
  827. depends on X86_64
  828. help
  829. Allow the kernel linear mapping to use 1GB pages on CPUs that
  830. support it. This can improve the kernel's performance a tiny bit by
  831. reducing TLB pressure. If in doubt, say "Y".
  832. # Common NUMA Features
  833. config NUMA
  834. bool "Numa Memory Allocation and Scheduler Support"
  835. depends on SMP
  836. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  837. default n if X86_PC
  838. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  839. help
  840. Enable NUMA (Non Uniform Memory Access) support.
  841. The kernel will try to allocate memory used by a CPU on the
  842. local memory controller of the CPU and add some more
  843. NUMA awareness to the kernel.
  844. For 64-bit this is recommended if the system is Intel Core i7
  845. (or later), AMD Opteron, or EM64T NUMA.
  846. For 32-bit this is only needed on (rare) 32-bit-only platforms
  847. that support NUMA topologies, such as NUMAQ / Summit, or if you
  848. boot a 32-bit kernel on a 64-bit NUMA platform.
  849. Otherwise, you should say N.
  850. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  851. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  852. config K8_NUMA
  853. def_bool y
  854. prompt "Old style AMD Opteron NUMA detection"
  855. depends on X86_64 && NUMA && PCI
  856. help
  857. Enable K8 NUMA node topology detection. You should say Y here if
  858. you have a multi processor AMD K8 system. This uses an old
  859. method to read the NUMA configuration directly from the builtin
  860. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  861. instead, which also takes priority if both are compiled in.
  862. config X86_64_ACPI_NUMA
  863. def_bool y
  864. prompt "ACPI NUMA detection"
  865. depends on X86_64 && NUMA && ACPI && PCI
  866. select ACPI_NUMA
  867. help
  868. Enable ACPI SRAT based node topology detection.
  869. # Some NUMA nodes have memory ranges that span
  870. # other nodes. Even though a pfn is valid and
  871. # between a node's start and end pfns, it may not
  872. # reside on that node. See memmap_init_zone()
  873. # for details.
  874. config NODES_SPAN_OTHER_NODES
  875. def_bool y
  876. depends on X86_64_ACPI_NUMA
  877. config NUMA_EMU
  878. bool "NUMA emulation"
  879. depends on X86_64 && NUMA
  880. help
  881. Enable NUMA emulation. A flat machine will be split
  882. into virtual nodes when booted with "numa=fake=N", where N is the
  883. number of nodes. This is only useful for debugging.
  884. config NODES_SHIFT
  885. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  886. range 1 9 if X86_64
  887. default "9" if MAXSMP
  888. default "6" if X86_64
  889. default "4" if X86_NUMAQ
  890. default "3"
  891. depends on NEED_MULTIPLE_NODES
  892. help
  893. Specify the maximum number of NUMA Nodes available on the target
  894. system. Increases memory reserved to accomodate various tables.
  895. config HAVE_ARCH_BOOTMEM_NODE
  896. def_bool y
  897. depends on X86_32 && NUMA
  898. config ARCH_HAVE_MEMORY_PRESENT
  899. def_bool y
  900. depends on X86_32 && DISCONTIGMEM
  901. config NEED_NODE_MEMMAP_SIZE
  902. def_bool y
  903. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  904. config HAVE_ARCH_ALLOC_REMAP
  905. def_bool y
  906. depends on X86_32 && NUMA
  907. config ARCH_FLATMEM_ENABLE
  908. def_bool y
  909. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  910. config ARCH_DISCONTIGMEM_ENABLE
  911. def_bool y
  912. depends on NUMA && X86_32
  913. config ARCH_DISCONTIGMEM_DEFAULT
  914. def_bool y
  915. depends on NUMA && X86_32
  916. config ARCH_SPARSEMEM_DEFAULT
  917. def_bool y
  918. depends on X86_64
  919. config ARCH_SPARSEMEM_ENABLE
  920. def_bool y
  921. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) || X86_GENERICARCH
  922. select SPARSEMEM_STATIC if X86_32
  923. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  924. config ARCH_SELECT_MEMORY_MODEL
  925. def_bool y
  926. depends on ARCH_SPARSEMEM_ENABLE
  927. config ARCH_MEMORY_PROBE
  928. def_bool X86_64
  929. depends on MEMORY_HOTPLUG
  930. source "mm/Kconfig"
  931. config HIGHPTE
  932. bool "Allocate 3rd-level pagetables from highmem"
  933. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  934. help
  935. The VM uses one page table entry for each page of physical memory.
  936. For systems with a lot of RAM, this can be wasteful of precious
  937. low memory. Setting this option will put user-space page table
  938. entries in high memory.
  939. config X86_CHECK_BIOS_CORRUPTION
  940. bool "Check for low memory corruption"
  941. help
  942. Periodically check for memory corruption in low memory, which
  943. is suspected to be caused by BIOS. Even when enabled in the
  944. configuration, it is disabled at runtime. Enable it by
  945. setting "memory_corruption_check=1" on the kernel command
  946. line. By default it scans the low 64k of memory every 60
  947. seconds; see the memory_corruption_check_size and
  948. memory_corruption_check_period parameters in
  949. Documentation/kernel-parameters.txt to adjust this.
  950. When enabled with the default parameters, this option has
  951. almost no overhead, as it reserves a relatively small amount
  952. of memory and scans it infrequently. It both detects corruption
  953. and prevents it from affecting the running system.
  954. It is, however, intended as a diagnostic tool; if repeatable
  955. BIOS-originated corruption always affects the same memory,
  956. you can use memmap= to prevent the kernel from using that
  957. memory.
  958. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  959. bool "Set the default setting of memory_corruption_check"
  960. depends on X86_CHECK_BIOS_CORRUPTION
  961. default y
  962. help
  963. Set whether the default state of memory_corruption_check is
  964. on or off.
  965. config X86_RESERVE_LOW_64K
  966. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  967. default y
  968. help
  969. Reserve the first 64K of physical RAM on BIOSes that are known
  970. to potentially corrupt that memory range. A numbers of BIOSes are
  971. known to utilize this area during suspend/resume, so it must not
  972. be used by the kernel.
  973. Set this to N if you are absolutely sure that you trust the BIOS
  974. to get all its memory reservations and usages right.
  975. If you have doubts about the BIOS (e.g. suspend/resume does not
  976. work or there's kernel crashes after certain hardware hotplug
  977. events) and it's not AMI or Phoenix, then you might want to enable
  978. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  979. corruption patterns.
  980. Say Y if unsure.
  981. config MATH_EMULATION
  982. bool
  983. prompt "Math emulation" if X86_32
  984. ---help---
  985. Linux can emulate a math coprocessor (used for floating point
  986. operations) if you don't have one. 486DX and Pentium processors have
  987. a math coprocessor built in, 486SX and 386 do not, unless you added
  988. a 487DX or 387, respectively. (The messages during boot time can
  989. give you some hints here ["man dmesg"].) Everyone needs either a
  990. coprocessor or this emulation.
  991. If you don't have a math coprocessor, you need to say Y here; if you
  992. say Y here even though you have a coprocessor, the coprocessor will
  993. be used nevertheless. (This behavior can be changed with the kernel
  994. command line option "no387", which comes handy if your coprocessor
  995. is broken. Try "man bootparam" or see the documentation of your boot
  996. loader (lilo or loadlin) about how to pass options to the kernel at
  997. boot time.) This means that it is a good idea to say Y here if you
  998. intend to use this kernel on different machines.
  999. More information about the internals of the Linux math coprocessor
  1000. emulation can be found in <file:arch/x86/math-emu/README>.
  1001. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1002. kernel, it won't hurt.
  1003. config MTRR
  1004. bool "MTRR (Memory Type Range Register) support"
  1005. ---help---
  1006. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1007. the Memory Type Range Registers (MTRRs) may be used to control
  1008. processor access to memory ranges. This is most useful if you have
  1009. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1010. allows bus write transfers to be combined into a larger transfer
  1011. before bursting over the PCI/AGP bus. This can increase performance
  1012. of image write operations 2.5 times or more. Saying Y here creates a
  1013. /proc/mtrr file which may be used to manipulate your processor's
  1014. MTRRs. Typically the X server should use this.
  1015. This code has a reasonably generic interface so that similar
  1016. control registers on other processors can be easily supported
  1017. as well:
  1018. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1019. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1020. these, the ARRs are used to emulate the MTRRs.
  1021. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1022. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1023. write-combining. All of these processors are supported by this code
  1024. and it makes sense to say Y here if you have one of them.
  1025. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1026. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1027. can lead to all sorts of problems, so it's good to say Y here.
  1028. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1029. just add about 9 KB to your kernel.
  1030. See <file:Documentation/x86/mtrr.txt> for more information.
  1031. config MTRR_SANITIZER
  1032. def_bool y
  1033. prompt "MTRR cleanup support"
  1034. depends on MTRR
  1035. help
  1036. Convert MTRR layout from continuous to discrete, so X drivers can
  1037. add writeback entries.
  1038. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1039. The largest mtrr entry size for a continous block can be set with
  1040. mtrr_chunk_size.
  1041. If unsure, say Y.
  1042. config MTRR_SANITIZER_ENABLE_DEFAULT
  1043. int "MTRR cleanup enable value (0-1)"
  1044. range 0 1
  1045. default "0"
  1046. depends on MTRR_SANITIZER
  1047. help
  1048. Enable mtrr cleanup default value
  1049. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1050. int "MTRR cleanup spare reg num (0-7)"
  1051. range 0 7
  1052. default "1"
  1053. depends on MTRR_SANITIZER
  1054. help
  1055. mtrr cleanup spare entries default, it can be changed via
  1056. mtrr_spare_reg_nr=N on the kernel command line.
  1057. config X86_PAT
  1058. bool
  1059. prompt "x86 PAT support"
  1060. depends on MTRR
  1061. help
  1062. Use PAT attributes to setup page level cache control.
  1063. PATs are the modern equivalents of MTRRs and are much more
  1064. flexible than MTRRs.
  1065. Say N here if you see bootup problems (boot crash, boot hang,
  1066. spontaneous reboots) or a non-working video driver.
  1067. If unsure, say Y.
  1068. config EFI
  1069. bool "EFI runtime service support"
  1070. depends on ACPI
  1071. ---help---
  1072. This enables the kernel to use EFI runtime services that are
  1073. available (such as the EFI variable services).
  1074. This option is only useful on systems that have EFI firmware.
  1075. In addition, you should use the latest ELILO loader available
  1076. at <http://elilo.sourceforge.net> in order to take advantage
  1077. of EFI runtime services. However, even with this option, the
  1078. resultant kernel should continue to boot on existing non-EFI
  1079. platforms.
  1080. config SECCOMP
  1081. def_bool y
  1082. prompt "Enable seccomp to safely compute untrusted bytecode"
  1083. help
  1084. This kernel feature is useful for number crunching applications
  1085. that may need to compute untrusted bytecode during their
  1086. execution. By using pipes or other transports made available to
  1087. the process as file descriptors supporting the read/write
  1088. syscalls, it's possible to isolate those applications in
  1089. their own address space using seccomp. Once seccomp is
  1090. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1091. and the task is only allowed to execute a few safe syscalls
  1092. defined by each seccomp mode.
  1093. If unsure, say Y. Only embedded should say N here.
  1094. config CC_STACKPROTECTOR_ALL
  1095. bool
  1096. config CC_STACKPROTECTOR
  1097. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1098. depends on X86_64
  1099. select CC_STACKPROTECTOR_ALL
  1100. help
  1101. This option turns on the -fstack-protector GCC feature. This
  1102. feature puts, at the beginning of functions, a canary value on
  1103. the stack just before the return address, and validates
  1104. the value just before actually returning. Stack based buffer
  1105. overflows (that need to overwrite this return address) now also
  1106. overwrite the canary, which gets detected and the attack is then
  1107. neutralized via a kernel panic.
  1108. This feature requires gcc version 4.2 or above, or a distribution
  1109. gcc with the feature backported. Older versions are automatically
  1110. detected and for those versions, this configuration option is
  1111. ignored. (and a warning is printed during bootup)
  1112. source kernel/Kconfig.hz
  1113. config KEXEC
  1114. bool "kexec system call"
  1115. help
  1116. kexec is a system call that implements the ability to shutdown your
  1117. current kernel, and to start another kernel. It is like a reboot
  1118. but it is independent of the system firmware. And like a reboot
  1119. you can start any kernel with it, not just Linux.
  1120. The name comes from the similarity to the exec system call.
  1121. It is an ongoing process to be certain the hardware in a machine
  1122. is properly shutdown, so do not be surprised if this code does not
  1123. initially work for you. It may help to enable device hotplugging
  1124. support. As of this writing the exact hardware interface is
  1125. strongly in flux, so no good recommendation can be made.
  1126. config CRASH_DUMP
  1127. bool "kernel crash dumps"
  1128. depends on X86_64 || (X86_32 && HIGHMEM)
  1129. help
  1130. Generate crash dump after being started by kexec.
  1131. This should be normally only set in special crash dump kernels
  1132. which are loaded in the main kernel with kexec-tools into
  1133. a specially reserved region and then later executed after
  1134. a crash by kdump/kexec. The crash dump kernel must be compiled
  1135. to a memory address not used by the main kernel or BIOS using
  1136. PHYSICAL_START, or it must be built as a relocatable image
  1137. (CONFIG_RELOCATABLE=y).
  1138. For more details see Documentation/kdump/kdump.txt
  1139. config KEXEC_JUMP
  1140. bool "kexec jump (EXPERIMENTAL)"
  1141. depends on EXPERIMENTAL
  1142. depends on KEXEC && HIBERNATION && X86_32
  1143. help
  1144. Jump between original kernel and kexeced kernel and invoke
  1145. code in physical address mode via KEXEC
  1146. config PHYSICAL_START
  1147. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1148. default "0x1000000" if X86_NUMAQ
  1149. default "0x200000" if X86_64
  1150. default "0x100000"
  1151. help
  1152. This gives the physical address where the kernel is loaded.
  1153. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1154. bzImage will decompress itself to above physical address and
  1155. run from there. Otherwise, bzImage will run from the address where
  1156. it has been loaded by the boot loader and will ignore above physical
  1157. address.
  1158. In normal kdump cases one does not have to set/change this option
  1159. as now bzImage can be compiled as a completely relocatable image
  1160. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1161. address. This option is mainly useful for the folks who don't want
  1162. to use a bzImage for capturing the crash dump and want to use a
  1163. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1164. to be specifically compiled to run from a specific memory area
  1165. (normally a reserved region) and this option comes handy.
  1166. So if you are using bzImage for capturing the crash dump, leave
  1167. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  1168. Otherwise if you plan to use vmlinux for capturing the crash dump
  1169. change this value to start of the reserved region (Typically 16MB
  1170. 0x1000000). In other words, it can be set based on the "X" value as
  1171. specified in the "crashkernel=YM@XM" command line boot parameter
  1172. passed to the panic-ed kernel. Typically this parameter is set as
  1173. crashkernel=64M@16M. Please take a look at
  1174. Documentation/kdump/kdump.txt for more details about crash dumps.
  1175. Usage of bzImage for capturing the crash dump is recommended as
  1176. one does not have to build two kernels. Same kernel can be used
  1177. as production kernel and capture kernel. Above option should have
  1178. gone away after relocatable bzImage support is introduced. But it
  1179. is present because there are users out there who continue to use
  1180. vmlinux for dump capture. This option should go away down the
  1181. line.
  1182. Don't change this unless you know what you are doing.
  1183. config RELOCATABLE
  1184. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1185. depends on EXPERIMENTAL
  1186. help
  1187. This builds a kernel image that retains relocation information
  1188. so it can be loaded someplace besides the default 1MB.
  1189. The relocations tend to make the kernel binary about 10% larger,
  1190. but are discarded at runtime.
  1191. One use is for the kexec on panic case where the recovery kernel
  1192. must live at a different physical address than the primary
  1193. kernel.
  1194. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1195. it has been loaded at and the compile time physical address
  1196. (CONFIG_PHYSICAL_START) is ignored.
  1197. config PHYSICAL_ALIGN
  1198. hex
  1199. prompt "Alignment value to which kernel should be aligned" if X86_32
  1200. default "0x100000" if X86_32
  1201. default "0x200000" if X86_64
  1202. range 0x2000 0x400000
  1203. help
  1204. This value puts the alignment restrictions on physical address
  1205. where kernel is loaded and run from. Kernel is compiled for an
  1206. address which meets above alignment restriction.
  1207. If bootloader loads the kernel at a non-aligned address and
  1208. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1209. address aligned to above value and run from there.
  1210. If bootloader loads the kernel at a non-aligned address and
  1211. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1212. load address and decompress itself to the address it has been
  1213. compiled for and run from there. The address for which kernel is
  1214. compiled already meets above alignment restrictions. Hence the
  1215. end result is that kernel runs from a physical address meeting
  1216. above alignment restrictions.
  1217. Don't change this unless you know what you are doing.
  1218. config HOTPLUG_CPU
  1219. bool "Support for hot-pluggable CPUs"
  1220. depends on SMP && HOTPLUG && !X86_VOYAGER
  1221. ---help---
  1222. Say Y here to allow turning CPUs off and on. CPUs can be
  1223. controlled through /sys/devices/system/cpu.
  1224. ( Note: power management support will enable this option
  1225. automatically on SMP systems. )
  1226. Say N if you want to disable CPU hotplug.
  1227. config COMPAT_VDSO
  1228. def_bool y
  1229. prompt "Compat VDSO support"
  1230. depends on X86_32 || IA32_EMULATION
  1231. help
  1232. Map the 32-bit VDSO to the predictable old-style address too.
  1233. ---help---
  1234. Say N here if you are running a sufficiently recent glibc
  1235. version (2.3.3 or later), to remove the high-mapped
  1236. VDSO mapping and to exclusively use the randomized VDSO.
  1237. If unsure, say Y.
  1238. config CMDLINE_BOOL
  1239. bool "Built-in kernel command line"
  1240. default n
  1241. help
  1242. Allow for specifying boot arguments to the kernel at
  1243. build time. On some systems (e.g. embedded ones), it is
  1244. necessary or convenient to provide some or all of the
  1245. kernel boot arguments with the kernel itself (that is,
  1246. to not rely on the boot loader to provide them.)
  1247. To compile command line arguments into the kernel,
  1248. set this option to 'Y', then fill in the
  1249. the boot arguments in CONFIG_CMDLINE.
  1250. Systems with fully functional boot loaders (i.e. non-embedded)
  1251. should leave this option set to 'N'.
  1252. config CMDLINE
  1253. string "Built-in kernel command string"
  1254. depends on CMDLINE_BOOL
  1255. default ""
  1256. help
  1257. Enter arguments here that should be compiled into the kernel
  1258. image and used at boot time. If the boot loader provides a
  1259. command line at boot time, it is appended to this string to
  1260. form the full kernel command line, when the system boots.
  1261. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1262. change this behavior.
  1263. In most cases, the command line (whether built-in or provided
  1264. by the boot loader) should specify the device for the root
  1265. file system.
  1266. config CMDLINE_OVERRIDE
  1267. bool "Built-in command line overrides boot loader arguments"
  1268. default n
  1269. depends on CMDLINE_BOOL
  1270. help
  1271. Set this option to 'Y' to have the kernel ignore the boot loader
  1272. command line, and use ONLY the built-in command line.
  1273. This is used to work around broken boot loaders. This should
  1274. be set to 'N' under normal conditions.
  1275. endmenu
  1276. config ARCH_ENABLE_MEMORY_HOTPLUG
  1277. def_bool y
  1278. depends on X86_64 || (X86_32 && HIGHMEM)
  1279. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1280. def_bool y
  1281. depends on MEMORY_HOTPLUG
  1282. config HAVE_ARCH_EARLY_PFN_TO_NID
  1283. def_bool X86_64
  1284. depends on NUMA
  1285. menu "Power management and ACPI options"
  1286. depends on !X86_VOYAGER
  1287. config ARCH_HIBERNATION_HEADER
  1288. def_bool y
  1289. depends on X86_64 && HIBERNATION
  1290. source "kernel/power/Kconfig"
  1291. source "drivers/acpi/Kconfig"
  1292. config X86_APM_BOOT
  1293. bool
  1294. default y
  1295. depends on APM || APM_MODULE
  1296. menuconfig APM
  1297. tristate "APM (Advanced Power Management) BIOS support"
  1298. depends on X86_32 && PM_SLEEP
  1299. ---help---
  1300. APM is a BIOS specification for saving power using several different
  1301. techniques. This is mostly useful for battery powered laptops with
  1302. APM compliant BIOSes. If you say Y here, the system time will be
  1303. reset after a RESUME operation, the /proc/apm device will provide
  1304. battery status information, and user-space programs will receive
  1305. notification of APM "events" (e.g. battery status change).
  1306. If you select "Y" here, you can disable actual use of the APM
  1307. BIOS by passing the "apm=off" option to the kernel at boot time.
  1308. Note that the APM support is almost completely disabled for
  1309. machines with more than one CPU.
  1310. In order to use APM, you will need supporting software. For location
  1311. and more information, read <file:Documentation/power/pm.txt> and the
  1312. Battery Powered Linux mini-HOWTO, available from
  1313. <http://www.tldp.org/docs.html#howto>.
  1314. This driver does not spin down disk drives (see the hdparm(8)
  1315. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1316. VESA-compliant "green" monitors.
  1317. This driver does not support the TI 4000M TravelMate and the ACER
  1318. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1319. desktop machines also don't have compliant BIOSes, and this driver
  1320. may cause those machines to panic during the boot phase.
  1321. Generally, if you don't have a battery in your machine, there isn't
  1322. much point in using this driver and you should say N. If you get
  1323. random kernel OOPSes or reboots that don't seem to be related to
  1324. anything, try disabling/enabling this option (or disabling/enabling
  1325. APM in your BIOS).
  1326. Some other things you should try when experiencing seemingly random,
  1327. "weird" problems:
  1328. 1) make sure that you have enough swap space and that it is
  1329. enabled.
  1330. 2) pass the "no-hlt" option to the kernel
  1331. 3) switch on floating point emulation in the kernel and pass
  1332. the "no387" option to the kernel
  1333. 4) pass the "floppy=nodma" option to the kernel
  1334. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1335. all but the first 4 MB of RAM)
  1336. 6) make sure that the CPU is not over clocked.
  1337. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1338. 8) disable the cache from your BIOS settings
  1339. 9) install a fan for the video card or exchange video RAM
  1340. 10) install a better fan for the CPU
  1341. 11) exchange RAM chips
  1342. 12) exchange the motherboard.
  1343. To compile this driver as a module, choose M here: the
  1344. module will be called apm.
  1345. if APM
  1346. config APM_IGNORE_USER_SUSPEND
  1347. bool "Ignore USER SUSPEND"
  1348. help
  1349. This option will ignore USER SUSPEND requests. On machines with a
  1350. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1351. series notebooks, it is necessary to say Y because of a BIOS bug.
  1352. config APM_DO_ENABLE
  1353. bool "Enable PM at boot time"
  1354. ---help---
  1355. Enable APM features at boot time. From page 36 of the APM BIOS
  1356. specification: "When disabled, the APM BIOS does not automatically
  1357. power manage devices, enter the Standby State, enter the Suspend
  1358. State, or take power saving steps in response to CPU Idle calls."
  1359. This driver will make CPU Idle calls when Linux is idle (unless this
  1360. feature is turned off -- see "Do CPU IDLE calls", below). This
  1361. should always save battery power, but more complicated APM features
  1362. will be dependent on your BIOS implementation. You may need to turn
  1363. this option off if your computer hangs at boot time when using APM
  1364. support, or if it beeps continuously instead of suspending. Turn
  1365. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1366. T400CDT. This is off by default since most machines do fine without
  1367. this feature.
  1368. config APM_CPU_IDLE
  1369. bool "Make CPU Idle calls when idle"
  1370. help
  1371. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1372. On some machines, this can activate improved power savings, such as
  1373. a slowed CPU clock rate, when the machine is idle. These idle calls
  1374. are made after the idle loop has run for some length of time (e.g.,
  1375. 333 mS). On some machines, this will cause a hang at boot time or
  1376. whenever the CPU becomes idle. (On machines with more than one CPU,
  1377. this option does nothing.)
  1378. config APM_DISPLAY_BLANK
  1379. bool "Enable console blanking using APM"
  1380. help
  1381. Enable console blanking using the APM. Some laptops can use this to
  1382. turn off the LCD backlight when the screen blanker of the Linux
  1383. virtual console blanks the screen. Note that this is only used by
  1384. the virtual console screen blanker, and won't turn off the backlight
  1385. when using the X Window system. This also doesn't have anything to
  1386. do with your VESA-compliant power-saving monitor. Further, this
  1387. option doesn't work for all laptops -- it might not turn off your
  1388. backlight at all, or it might print a lot of errors to the console,
  1389. especially if you are using gpm.
  1390. config APM_ALLOW_INTS
  1391. bool "Allow interrupts during APM BIOS calls"
  1392. help
  1393. Normally we disable external interrupts while we are making calls to
  1394. the APM BIOS as a measure to lessen the effects of a badly behaving
  1395. BIOS implementation. The BIOS should reenable interrupts if it
  1396. needs to. Unfortunately, some BIOSes do not -- especially those in
  1397. many of the newer IBM Thinkpads. If you experience hangs when you
  1398. suspend, try setting this to Y. Otherwise, say N.
  1399. endif # APM
  1400. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1401. source "drivers/cpuidle/Kconfig"
  1402. source "drivers/idle/Kconfig"
  1403. endmenu
  1404. menu "Bus options (PCI etc.)"
  1405. config PCI
  1406. bool "PCI support"
  1407. default y
  1408. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1409. help
  1410. Find out whether you have a PCI motherboard. PCI is the name of a
  1411. bus system, i.e. the way the CPU talks to the other stuff inside
  1412. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1413. VESA. If you have PCI, say Y, otherwise N.
  1414. choice
  1415. prompt "PCI access mode"
  1416. depends on X86_32 && PCI
  1417. default PCI_GOANY
  1418. ---help---
  1419. On PCI systems, the BIOS can be used to detect the PCI devices and
  1420. determine their configuration. However, some old PCI motherboards
  1421. have BIOS bugs and may crash if this is done. Also, some embedded
  1422. PCI-based systems don't have any BIOS at all. Linux can also try to
  1423. detect the PCI hardware directly without using the BIOS.
  1424. With this option, you can specify how Linux should detect the
  1425. PCI devices. If you choose "BIOS", the BIOS will be used,
  1426. if you choose "Direct", the BIOS won't be used, and if you
  1427. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1428. If you choose "Any", the kernel will try MMCONFIG, then the
  1429. direct access method and falls back to the BIOS if that doesn't
  1430. work. If unsure, go with the default, which is "Any".
  1431. config PCI_GOBIOS
  1432. bool "BIOS"
  1433. config PCI_GOMMCONFIG
  1434. bool "MMConfig"
  1435. config PCI_GODIRECT
  1436. bool "Direct"
  1437. config PCI_GOOLPC
  1438. bool "OLPC"
  1439. depends on OLPC
  1440. config PCI_GOANY
  1441. bool "Any"
  1442. endchoice
  1443. config PCI_BIOS
  1444. def_bool y
  1445. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1446. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1447. config PCI_DIRECT
  1448. def_bool y
  1449. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1450. config PCI_MMCONFIG
  1451. def_bool y
  1452. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1453. config PCI_OLPC
  1454. def_bool y
  1455. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1456. config PCI_DOMAINS
  1457. def_bool y
  1458. depends on PCI
  1459. config PCI_MMCONFIG
  1460. bool "Support mmconfig PCI config space access"
  1461. depends on X86_64 && PCI && ACPI
  1462. config DMAR
  1463. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1464. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1465. help
  1466. DMA remapping (DMAR) devices support enables independent address
  1467. translations for Direct Memory Access (DMA) from devices.
  1468. These DMA remapping devices are reported via ACPI tables
  1469. and include PCI device scope covered by these DMA
  1470. remapping devices.
  1471. config DMAR_GFX_WA
  1472. def_bool y
  1473. prompt "Support for Graphics workaround"
  1474. depends on DMAR
  1475. help
  1476. Current Graphics drivers tend to use physical address
  1477. for DMA and avoid using DMA APIs. Setting this config
  1478. option permits the IOMMU driver to set a unity map for
  1479. all the OS-visible memory. Hence the driver can continue
  1480. to use physical addresses for DMA.
  1481. config DMAR_FLOPPY_WA
  1482. def_bool y
  1483. depends on DMAR
  1484. help
  1485. Floppy disk drivers are know to bypass DMA API calls
  1486. thereby failing to work when IOMMU is enabled. This
  1487. workaround will setup a 1:1 mapping for the first
  1488. 16M to make floppy (an ISA device) work.
  1489. config INTR_REMAP
  1490. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1491. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1492. help
  1493. Supports Interrupt remapping for IO-APIC and MSI devices.
  1494. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1495. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1496. source "drivers/pci/pcie/Kconfig"
  1497. source "drivers/pci/Kconfig"
  1498. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1499. config ISA_DMA_API
  1500. def_bool y
  1501. if X86_32
  1502. config ISA
  1503. bool "ISA support"
  1504. depends on !X86_VOYAGER
  1505. help
  1506. Find out whether you have ISA slots on your motherboard. ISA is the
  1507. name of a bus system, i.e. the way the CPU talks to the other stuff
  1508. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1509. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1510. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1511. config EISA
  1512. bool "EISA support"
  1513. depends on ISA
  1514. ---help---
  1515. The Extended Industry Standard Architecture (EISA) bus was
  1516. developed as an open alternative to the IBM MicroChannel bus.
  1517. The EISA bus provided some of the features of the IBM MicroChannel
  1518. bus while maintaining backward compatibility with cards made for
  1519. the older ISA bus. The EISA bus saw limited use between 1988 and
  1520. 1995 when it was made obsolete by the PCI bus.
  1521. Say Y here if you are building a kernel for an EISA-based machine.
  1522. Otherwise, say N.
  1523. source "drivers/eisa/Kconfig"
  1524. config MCA
  1525. bool "MCA support"
  1526. help
  1527. MicroChannel Architecture is found in some IBM PS/2 machines and
  1528. laptops. It is a bus system similar to PCI or ISA. See
  1529. <file:Documentation/mca.txt> (and especially the web page given
  1530. there) before attempting to build an MCA bus kernel.
  1531. source "drivers/mca/Kconfig"
  1532. config SCx200
  1533. tristate "NatSemi SCx200 support"
  1534. help
  1535. This provides basic support for National Semiconductor's
  1536. (now AMD's) Geode processors. The driver probes for the
  1537. PCI-IDs of several on-chip devices, so its a good dependency
  1538. for other scx200_* drivers.
  1539. If compiled as a module, the driver is named scx200.
  1540. config SCx200HR_TIMER
  1541. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1542. depends on SCx200 && GENERIC_TIME
  1543. default y
  1544. help
  1545. This driver provides a clocksource built upon the on-chip
  1546. 27MHz high-resolution timer. Its also a workaround for
  1547. NSC Geode SC-1100's buggy TSC, which loses time when the
  1548. processor goes idle (as is done by the scheduler). The
  1549. other workaround is idle=poll boot option.
  1550. config GEODE_MFGPT_TIMER
  1551. def_bool y
  1552. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1553. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1554. help
  1555. This driver provides a clock event source based on the MFGPT
  1556. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1557. MFGPTs have a better resolution and max interval than the
  1558. generic PIT, and are suitable for use as high-res timers.
  1559. config OLPC
  1560. bool "One Laptop Per Child support"
  1561. default n
  1562. help
  1563. Add support for detecting the unique features of the OLPC
  1564. XO hardware.
  1565. endif # X86_32
  1566. config K8_NB
  1567. def_bool y
  1568. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1569. source "drivers/pcmcia/Kconfig"
  1570. source "drivers/pci/hotplug/Kconfig"
  1571. endmenu
  1572. menu "Executable file formats / Emulations"
  1573. source "fs/Kconfig.binfmt"
  1574. config IA32_EMULATION
  1575. bool "IA32 Emulation"
  1576. depends on X86_64
  1577. select COMPAT_BINFMT_ELF
  1578. help
  1579. Include code to run 32-bit programs under a 64-bit kernel. You should
  1580. likely turn this on, unless you're 100% sure that you don't have any
  1581. 32-bit programs left.
  1582. config IA32_AOUT
  1583. tristate "IA32 a.out support"
  1584. depends on IA32_EMULATION
  1585. help
  1586. Support old a.out binaries in the 32bit emulation.
  1587. config COMPAT
  1588. def_bool y
  1589. depends on IA32_EMULATION
  1590. config COMPAT_FOR_U64_ALIGNMENT
  1591. def_bool COMPAT
  1592. depends on X86_64
  1593. config SYSVIPC_COMPAT
  1594. def_bool y
  1595. depends on COMPAT && SYSVIPC
  1596. endmenu
  1597. config HAVE_ATOMIC_IOMAP
  1598. def_bool y
  1599. depends on X86_32
  1600. source "net/Kconfig"
  1601. source "drivers/Kconfig"
  1602. source "drivers/firmware/Kconfig"
  1603. source "fs/Kconfig"
  1604. source "arch/x86/Kconfig.debug"
  1605. source "security/Kconfig"
  1606. source "crypto/Kconfig"
  1607. source "arch/x86/kvm/Kconfig"
  1608. source "lib/Kconfig"