3 bool "64-bit kernel" if ARCH = "x86"
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
18 select X86_DEV_DMA_OPS
19 select ARCH_USE_CMPXCHG_LOCKREF
25 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
27 select ARCH_HAS_FAST_MULTIPLIER
28 select ARCH_HAS_GCOV_PROFILE_ALL
29 select ARCH_MIGHT_HAVE_PC_PARPORT
30 select ARCH_MIGHT_HAVE_PC_SERIO
31 select HAVE_AOUT if X86_32
32 select HAVE_UNSTABLE_SCHED_CLOCK
33 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
34 select ARCH_SUPPORTS_INT128 if X86_64
37 select HAVE_PCSPKR_PLATFORM
38 select HAVE_PERF_EVENTS
39 select HAVE_IOREMAP_PROT
42 select HAVE_MEMBLOCK_NODE_MAP
43 select ARCH_DISCARD_MEMBLOCK
44 select ARCH_WANT_OPTIONAL_GPIOLIB
45 select ARCH_WANT_FRAME_POINTERS
47 select HAVE_DMA_CONTIGUOUS
48 select HAVE_KRETPROBES
49 select GENERIC_EARLY_IOREMAP
51 select HAVE_KPROBES_ON_FTRACE
52 select HAVE_FTRACE_MCOUNT_RECORD
53 select HAVE_FENTRY if X86_64
54 select HAVE_C_RECORDMCOUNT
55 select HAVE_DYNAMIC_FTRACE
56 select HAVE_DYNAMIC_FTRACE_WITH_REGS
57 select HAVE_FUNCTION_TRACER
58 select HAVE_FUNCTION_GRAPH_TRACER
59 select HAVE_FUNCTION_GRAPH_FP_TEST
60 select HAVE_SYSCALL_TRACEPOINTS
61 select SYSCTL_EXCEPTION_TRACE
64 select HAVE_ARCH_TRACEHOOK
65 select HAVE_GENERIC_DMA_COHERENT if X86_32
66 select HAVE_EFFICIENT_UNALIGNED_ACCESS
67 select USER_STACKTRACE_SUPPORT
68 select HAVE_REGS_AND_STACK_ACCESS_API
69 select HAVE_DMA_API_DEBUG
70 select HAVE_KERNEL_GZIP
71 select HAVE_KERNEL_BZIP2
72 select HAVE_KERNEL_LZMA
74 select HAVE_KERNEL_LZO
75 select HAVE_KERNEL_LZ4
76 select HAVE_HW_BREAKPOINT
77 select HAVE_MIXED_BREAKPOINTS_REGS
79 select HAVE_PERF_EVENTS_NMI
81 select HAVE_PERF_USER_STACK_DUMP
82 select HAVE_DEBUG_KMEMLEAK
84 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
85 select HAVE_CMPXCHG_LOCAL
86 select HAVE_CMPXCHG_DOUBLE
87 select HAVE_ARCH_KMEMCHECK
88 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
89 select HAVE_USER_RETURN_NOTIFIER
90 select ARCH_HAS_ELF_RANDOMIZE
91 select HAVE_ARCH_JUMP_LABEL
92 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
94 select GENERIC_FIND_FIRST_BIT
95 select GENERIC_IRQ_PROBE
96 select GENERIC_PENDING_IRQ if SMP
97 select GENERIC_IRQ_SHOW
98 select GENERIC_CLOCKEVENTS_MIN_ADJUST
99 select IRQ_FORCED_THREADING
100 select HAVE_BPF_JIT if X86_64
101 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
102 select HAVE_ARCH_HUGE_VMAP if X86_64 || (X86_32 && X86_PAE)
103 select ARCH_HAS_SG_CHAIN
105 select ARCH_HAVE_NMI_SAFE_CMPXCHG
107 select DCACHE_WORD_ACCESS
108 select GENERIC_SMP_IDLE_THREAD
109 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
110 select HAVE_ARCH_SECCOMP_FILTER
111 select BUILDTIME_EXTABLE_SORT
112 select GENERIC_CMOS_UPDATE
113 select HAVE_ARCH_SOFT_DIRTY if X86_64
114 select CLOCKSOURCE_WATCHDOG
115 select GENERIC_CLOCKEVENTS
116 select ARCH_CLOCKSOURCE_DATA
117 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
118 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
119 select GENERIC_TIME_VSYSCALL
120 select GENERIC_STRNCPY_FROM_USER
121 select GENERIC_STRNLEN_USER
122 select HAVE_CONTEXT_TRACKING if X86_64
123 select HAVE_IRQ_TIME_ACCOUNTING
125 select MODULES_USE_ELF_REL if X86_32
126 select MODULES_USE_ELF_RELA if X86_64
127 select CLONE_BACKWARDS if X86_32
128 select ARCH_USE_BUILTIN_BSWAP
129 select ARCH_USE_QUEUE_RWLOCK
130 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
131 select OLD_SIGACTION if X86_32
132 select COMPAT_OLD_SIGACTION if IA32_EMULATION
134 select HAVE_DEBUG_STACKOVERFLOW
135 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
136 select HAVE_CC_STACKPROTECTOR
137 select GENERIC_CPU_AUTOPROBE
138 select HAVE_ARCH_AUDITSYSCALL
139 select ARCH_SUPPORTS_ATOMIC_RMW
140 select HAVE_ACPI_APEI if ACPI
141 select HAVE_ACPI_APEI_NMI if ACPI
142 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
143 select X86_FEATURE_NAMES if PROC_FS
146 config INSTRUCTION_DECODER
148 depends on KPROBES || PERF_EVENTS || UPROBES
150 config PERF_EVENTS_INTEL_UNCORE
152 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
156 default "elf32-i386" if X86_32
157 default "elf64-x86-64" if X86_64
159 config ARCH_DEFCONFIG
161 default "arch/x86/configs/i386_defconfig" if X86_32
162 default "arch/x86/configs/x86_64_defconfig" if X86_64
164 config LOCKDEP_SUPPORT
167 config STACKTRACE_SUPPORT
170 config HAVE_LATENCYTOP_SUPPORT
179 config NEED_DMA_MAP_STATE
181 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
183 config NEED_SG_DMA_LENGTH
186 config GENERIC_ISA_DMA
188 depends on ISA_DMA_API
193 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
195 config GENERIC_BUG_RELATIVE_POINTERS
198 config GENERIC_HWEIGHT
201 config ARCH_MAY_HAVE_PC_FDC
203 depends on ISA_DMA_API
205 config RWSEM_XCHGADD_ALGORITHM
208 config GENERIC_CALIBRATE_DELAY
211 config ARCH_HAS_CPU_RELAX
214 config ARCH_HAS_CACHE_LINE_SIZE
217 config HAVE_SETUP_PER_CPU_AREA
220 config NEED_PER_CPU_EMBED_FIRST_CHUNK
223 config NEED_PER_CPU_PAGE_FIRST_CHUNK
226 config ARCH_HIBERNATION_POSSIBLE
229 config ARCH_SUSPEND_POSSIBLE
232 config ARCH_WANT_HUGE_PMD_SHARE
235 config ARCH_WANT_GENERAL_HUGETLB
244 config ARCH_SUPPORTS_OPTIMIZED_INLINING
247 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
250 config HAVE_INTEL_TXT
252 depends on INTEL_IOMMU && ACPI
256 depends on X86_32 && SMP
260 depends on X86_64 && SMP
266 config X86_32_LAZY_GS
268 depends on X86_32 && !CC_STACKPROTECTOR
270 config ARCH_HWEIGHT_CFLAGS
272 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
273 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
275 config ARCH_SUPPORTS_UPROBES
278 config FIX_EARLYCON_MEM
281 config PGTABLE_LEVELS
287 source "init/Kconfig"
288 source "kernel/Kconfig.freezer"
290 menu "Processor type and features"
293 bool "DMA memory allocation support" if EXPERT
296 DMA memory allocation support allows devices with less than 32-bit
297 addressing to allocate within the first 16MB of address space.
298 Disable if no such devices will be used.
303 bool "Symmetric multi-processing support"
305 This enables support for systems with more than one CPU. If you have
306 a system with only one CPU, say N. If you have a system with more
309 If you say N here, the kernel will run on uni- and multiprocessor
310 machines, but will use only one CPU of a multiprocessor machine. If
311 you say Y here, the kernel will run on many, but not all,
312 uniprocessor machines. On a uniprocessor machine, the kernel
313 will run faster if you say N here.
315 Note that if you say Y here and choose architecture "586" or
316 "Pentium" under "Processor family", the kernel will not work on 486
317 architectures. Similarly, multiprocessor kernels for the "PPro"
318 architecture may not work on all Pentium based boards.
320 People using multiprocessor machines who say Y here should also say
321 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
322 Management" code will be disabled if you say Y here.
324 See also <file:Documentation/x86/i386/IO-APIC.txt>,
325 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
326 <http://www.tldp.org/docs.html#howto>.
328 If you don't know what to do here, say N.
330 config X86_FEATURE_NAMES
331 bool "Processor feature human-readable names" if EMBEDDED
334 This option compiles in a table of x86 feature bits and corresponding
335 names. This is required to support /proc/cpuinfo and a few kernel
336 messages. You can disable this to save space, at the expense of
337 making those few kernel messages show numeric feature bits instead.
342 bool "Support x2apic"
343 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
345 This enables x2apic support on CPUs that have this feature.
347 This allows 32-bit apic IDs (so it can support very large systems),
348 and accesses the local apic via MSRs not via mmio.
350 If you don't know what to do here, say N.
353 bool "Enable MPS table" if ACPI || SFI
355 depends on X86_LOCAL_APIC
357 For old smp systems that do not have proper acpi support. Newer systems
358 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
361 bool "Support for big SMP systems with more than 8 CPUs"
362 depends on X86_32 && SMP
364 This option is needed for the systems that have more than 8 CPUs
368 depends on X86_GOLDFISH
371 config X86_EXTENDED_PLATFORM
372 bool "Support for extended (non-PC) x86 platforms"
375 If you disable this option then the kernel will only support
376 standard PC platforms. (which covers the vast majority of
379 If you enable this option then you'll be able to select support
380 for the following (non-PC) 32 bit x86 platforms:
381 Goldfish (Android emulator)
384 SGI 320/540 (Visual Workstation)
385 STA2X11-based (e.g. Northville)
386 Moorestown MID devices
388 If you have one of these systems, or if you want to build a
389 generic distribution kernel, say Y here - otherwise say N.
393 config X86_EXTENDED_PLATFORM
394 bool "Support for extended (non-PC) x86 platforms"
397 If you disable this option then the kernel will only support
398 standard PC platforms. (which covers the vast majority of
401 If you enable this option then you'll be able to select support
402 for the following (non-PC) 64 bit x86 platforms:
407 If you have one of these systems, or if you want to build a
408 generic distribution kernel, say Y here - otherwise say N.
410 # This is an alphabetically sorted list of 64 bit extended platforms
411 # Please maintain the alphabetic order if and when there are additions
413 bool "Numascale NumaChip"
415 depends on X86_EXTENDED_PLATFORM
418 depends on X86_X2APIC
419 depends on PCI_MMCONFIG
421 Adds support for Numascale NumaChip large-SMP systems. Needed to
422 enable more than ~168 cores.
423 If you don't have one of these, you should say N here.
427 select HYPERVISOR_GUEST
429 depends on X86_64 && PCI
430 depends on X86_EXTENDED_PLATFORM
433 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
434 supposed to run on these EM64T-based machines. Only choose this option
435 if you have one of these machines.
438 bool "SGI Ultraviolet"
440 depends on X86_EXTENDED_PLATFORM
442 depends on X86_X2APIC
444 This option is needed in order to support SGI Ultraviolet systems.
445 If you don't have one of these, you should say N here.
447 # Following is an alphabetically sorted list of 32 bit extended platforms
448 # Please maintain the alphabetic order if and when there are additions
451 bool "Goldfish (Virtual Platform)"
452 depends on X86_EXTENDED_PLATFORM
454 Enable support for the Goldfish virtual platform used primarily
455 for Android development. Unless you are building for the Android
456 Goldfish emulator say N here.
459 bool "CE4100 TV platform"
461 depends on PCI_GODIRECT
462 depends on X86_IO_APIC
464 depends on X86_EXTENDED_PLATFORM
465 select X86_REBOOTFIXUPS
467 select OF_EARLY_FLATTREE
470 Select for the Intel CE media processor (CE4100) SOC.
471 This option compiles in support for the CE4100 SOC for settop
472 boxes and media devices.
475 bool "Intel MID platform support"
477 depends on X86_EXTENDED_PLATFORM
478 depends on X86_PLATFORM_DEVICES
481 depends on X86_IO_APIC
487 select MFD_INTEL_MSIC
489 Select to build a kernel capable of supporting Intel MID (Mobile
490 Internet Device) platform systems which do not have the PCI legacy
491 interfaces. If you are building for a PC class system say N here.
493 Intel MID platforms are based on an Intel processor and chipset which
494 consume less power than most of the x86 derivatives.
496 config X86_INTEL_QUARK
497 bool "Intel Quark platform support"
499 depends on X86_EXTENDED_PLATFORM
500 depends on X86_PLATFORM_DEVICES
504 depends on X86_IO_APIC
509 Select to include support for Quark X1000 SoC.
510 Say Y here if you have a Quark based system such as the Arduino
511 compatible Intel Galileo.
513 config X86_INTEL_LPSS
514 bool "Intel Low Power Subsystem Support"
519 Select to build support for Intel Low Power Subsystem such as
520 found on Intel Lynxpoint PCH. Selecting this option enables
521 things like clock tree (common clock framework) and pincontrol
522 which are needed by the LPSS peripheral drivers.
524 config X86_AMD_PLATFORM_DEVICE
525 bool "AMD ACPI2Platform devices support"
530 Select to interpret AMD specific ACPI device to platform device
531 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
532 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
533 implemented under PINCTRL subsystem.
536 tristate "Intel SoC IOSF Sideband support for SoC platforms"
539 This option enables sideband register access support for Intel SoC
540 platforms. On these platforms the IOSF sideband is used in lieu of
541 MSR's for some register accesses, mostly but not limited to thermal
542 and power. Drivers may query the availability of this device to
543 determine if they need the sideband in order to work on these
544 platforms. The sideband is available on the following SoC products.
545 This list is not meant to be exclusive.
550 You should say Y if you are running a kernel on one of these SoC's.
552 config IOSF_MBI_DEBUG
553 bool "Enable IOSF sideband access through debugfs"
554 depends on IOSF_MBI && DEBUG_FS
556 Select this option to expose the IOSF sideband access registers (MCR,
557 MDR, MCRX) through debugfs to write and read register information from
558 different units on the SoC. This is most useful for obtaining device
559 state information for debug and analysis. As this is a general access
560 mechanism, users of this option would have specific knowledge of the
561 device they want to access.
563 If you don't require the option or are in doubt, say N.
566 bool "RDC R-321x SoC"
568 depends on X86_EXTENDED_PLATFORM
570 select X86_REBOOTFIXUPS
572 This option is needed for RDC R-321x system-on-chip, also known
574 If you don't have one of these chips, you should say N here.
576 config X86_32_NON_STANDARD
577 bool "Support non-standard 32-bit SMP architectures"
578 depends on X86_32 && SMP
579 depends on X86_EXTENDED_PLATFORM
581 This option compiles in the bigsmp and STA2X11 default
582 subarchitectures. It is intended for a generic binary
583 kernel. If you select them all, kernel will probe it one by
584 one and will fallback to default.
586 # Alphabetically sorted list of Non standard 32 bit platforms
588 config X86_SUPPORTS_MEMORY_FAILURE
590 # MCE code calls memory_failure():
592 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
593 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
594 depends on X86_64 || !SPARSEMEM
595 select ARCH_SUPPORTS_MEMORY_FAILURE
598 bool "STA2X11 Companion Chip Support"
599 depends on X86_32_NON_STANDARD && PCI
600 select X86_DEV_DMA_OPS
604 select ARCH_REQUIRE_GPIOLIB
607 This adds support for boards based on the STA2X11 IO-Hub,
608 a.k.a. "ConneXt". The chip is used in place of the standard
609 PC chipset, so all "standard" peripherals are missing. If this
610 option is selected the kernel will still be able to boot on
611 standard PC machines.
614 tristate "Eurobraille/Iris poweroff module"
617 The Iris machines from EuroBraille do not have APM or ACPI support
618 to shut themselves down properly. A special I/O sequence is
619 needed to do so, which is what this module does at
622 This is only for Iris machines from EuroBraille.
626 config SCHED_OMIT_FRAME_POINTER
628 prompt "Single-depth WCHAN output"
631 Calculate simpler /proc/<PID>/wchan values. If this option
632 is disabled then wchan values will recurse back to the
633 caller function. This provides more accurate wchan values,
634 at the expense of slightly more scheduling overhead.
636 If in doubt, say "Y".
638 menuconfig HYPERVISOR_GUEST
639 bool "Linux guest support"
641 Say Y here to enable options for running Linux under various hyper-
642 visors. This option enables basic hypervisor detection and platform
645 If you say N, all options in this submenu will be skipped and
646 disabled, and Linux guest support won't be built in.
651 bool "Enable paravirtualization code"
653 This changes the kernel so it can modify itself when it is run
654 under a hypervisor, potentially improving performance significantly
655 over full virtualization. However, when run without a hypervisor
656 the kernel is theoretically slower and slightly larger.
658 config PARAVIRT_DEBUG
659 bool "paravirt-ops debugging"
660 depends on PARAVIRT && DEBUG_KERNEL
662 Enable to debug paravirt_ops internals. Specifically, BUG if
663 a paravirt_op is missing when it is called.
665 config PARAVIRT_SPINLOCKS
666 bool "Paravirtualization layer for spinlocks"
667 depends on PARAVIRT && SMP
668 select UNINLINE_SPIN_UNLOCK
670 Paravirtualized spinlocks allow a pvops backend to replace the
671 spinlock implementation with something virtualization-friendly
672 (for example, block the virtual CPU rather than spinning).
674 It has a minimal impact on native kernels and gives a nice performance
675 benefit on paravirtualized KVM / Xen kernels.
677 If you are unsure how to answer this question, answer Y.
679 source "arch/x86/xen/Kconfig"
682 bool "KVM Guest support (including kvmclock)"
684 select PARAVIRT_CLOCK
687 This option enables various optimizations for running under the KVM
688 hypervisor. It includes a paravirtualized clock, so that instead
689 of relying on a PIT (or probably other) emulation by the
690 underlying device model, the host provides the guest with
691 timing infrastructure such as time of day, and system time
694 bool "Enable debug information for KVM Guests in debugfs"
695 depends on KVM_GUEST && DEBUG_FS
698 This option enables collection of various statistics for KVM guest.
699 Statistics are displayed in debugfs filesystem. Enabling this option
700 may incur significant overhead.
702 source "arch/x86/lguest/Kconfig"
704 config PARAVIRT_TIME_ACCOUNTING
705 bool "Paravirtual steal time accounting"
709 Select this option to enable fine granularity task steal time
710 accounting. Time spent executing other tasks in parallel with
711 the current vCPU is discounted from the vCPU power. To account for
712 that, there can be a small performance impact.
714 If in doubt, say N here.
716 config PARAVIRT_CLOCK
719 endif #HYPERVISOR_GUEST
724 source "arch/x86/Kconfig.cpu"
728 prompt "HPET Timer Support" if X86_32
730 Use the IA-PC HPET (High Precision Event Timer) to manage
731 time in preference to the PIT and RTC, if a HPET is
733 HPET is the next generation timer replacing legacy 8254s.
734 The HPET provides a stable time base on SMP
735 systems, unlike the TSC, but it is more expensive to access,
736 as it is off-chip. You can find the HPET spec at
737 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
739 You can safely choose Y here. However, HPET will only be
740 activated if the platform and the BIOS support this feature.
741 Otherwise the 8254 will be used for timing services.
743 Choose N to continue using the legacy 8254 timer.
745 config HPET_EMULATE_RTC
747 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
750 def_bool y if X86_INTEL_MID
751 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
753 depends on X86_INTEL_MID && SFI
755 APB timer is the replacement for 8254, HPET on X86 MID platforms.
756 The APBT provides a stable time base on SMP
757 systems, unlike the TSC, but it is more expensive to access,
758 as it is off-chip. APB timers are always running regardless of CPU
759 C states, they are used as per CPU clockevent device when possible.
761 # Mark as expert because too many people got it wrong.
762 # The code disables itself when not needed.
765 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
766 bool "Enable DMI scanning" if EXPERT
768 Enabled scanning of DMI to identify machine quirks. Say Y
769 here unless you have verified that your setup is not
770 affected by entries in the DMI blacklist. Required by PNP
774 bool "Old AMD GART IOMMU support"
776 depends on X86_64 && PCI && AMD_NB
778 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
779 GART based hardware IOMMUs.
781 The GART supports full DMA access for devices with 32-bit access
782 limitations, on systems with more than 3 GB. This is usually needed
783 for USB, sound, many IDE/SATA chipsets and some other devices.
785 Newer systems typically have a modern AMD IOMMU, supported via
786 the CONFIG_AMD_IOMMU=y config option.
788 In normal configurations this driver is only active when needed:
789 there's more than 3 GB of memory and the system contains a
790 32-bit limited device.
795 bool "IBM Calgary IOMMU support"
797 depends on X86_64 && PCI
799 Support for hardware IOMMUs in IBM's xSeries x366 and x460
800 systems. Needed to run systems with more than 3GB of memory
801 properly with 32-bit PCI devices that do not support DAC
802 (Double Address Cycle). Calgary also supports bus level
803 isolation, where all DMAs pass through the IOMMU. This
804 prevents them from going anywhere except their intended
805 destination. This catches hard-to-find kernel bugs and
806 mis-behaving drivers and devices that do not use the DMA-API
807 properly to set up their DMA buffers. The IOMMU can be
808 turned off at boot time with the iommu=off parameter.
809 Normally the kernel will make the right choice by itself.
812 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
814 prompt "Should Calgary be enabled by default?"
815 depends on CALGARY_IOMMU
817 Should Calgary be enabled by default? if you choose 'y', Calgary
818 will be used (if it exists). If you choose 'n', Calgary will not be
819 used even if it exists. If you choose 'n' and would like to use
820 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
823 # need this always selected by IOMMU for the VIA workaround
827 Support for software bounce buffers used on x86-64 systems
828 which don't have a hardware IOMMU. Using this PCI devices
829 which can only access 32-bits of memory can be used on systems
830 with more than 3 GB of memory.
835 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
838 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
839 depends on X86_64 && SMP && DEBUG_KERNEL
840 select CPUMASK_OFFSTACK
842 Enable maximum number of CPUS and NUMA Nodes for this architecture.
846 int "Maximum number of CPUs" if SMP && !MAXSMP
847 range 2 8 if SMP && X86_32 && !X86_BIGSMP
848 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
849 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
851 default "8192" if MAXSMP
852 default "32" if SMP && X86_BIGSMP
855 This allows you to specify the maximum number of CPUs which this
856 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
857 supported value is 4096, otherwise the maximum value is 512. The
858 minimum value which makes sense is 2.
860 This is purely to save memory - each supported CPU adds
861 approximately eight kilobytes to the kernel image.
864 bool "SMT (Hyperthreading) scheduler support"
867 SMT scheduler support improves the CPU scheduler's decision making
868 when dealing with Intel Pentium 4 chips with HyperThreading at a
869 cost of slightly increased overhead in some places. If unsure say
874 prompt "Multi-core scheduler support"
877 Multi-core scheduler support improves the CPU scheduler's decision
878 making when dealing with multi-core CPU chips at a cost of slightly
879 increased overhead in some places. If unsure say N here.
881 source "kernel/Kconfig.preempt"
885 depends on !SMP && X86_LOCAL_APIC
888 bool "Local APIC support on uniprocessors" if !PCI_MSI
890 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
892 A local APIC (Advanced Programmable Interrupt Controller) is an
893 integrated interrupt controller in the CPU. If you have a single-CPU
894 system which has a processor with a local APIC, you can say Y here to
895 enable and use it. If you say Y here even though your machine doesn't
896 have a local APIC, then the kernel will still run with no slowdown at
897 all. The local APIC supports CPU-generated self-interrupts (timer,
898 performance counters), and the NMI watchdog which detects hard
902 bool "IO-APIC support on uniprocessors"
903 depends on X86_UP_APIC
905 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
906 SMP-capable replacement for PC-style interrupt controllers. Most
907 SMP systems and many recent uniprocessor systems have one.
909 If you have a single-CPU system with an IO-APIC, you can say Y here
910 to use it. If you say Y here even though your machine doesn't have
911 an IO-APIC, then the kernel will still run with no slowdown at all.
913 config X86_LOCAL_APIC
915 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
916 select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
920 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
923 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
924 bool "Reroute for broken boot IRQs"
925 depends on X86_IO_APIC
927 This option enables a workaround that fixes a source of
928 spurious interrupts. This is recommended when threaded
929 interrupt handling is used on systems where the generation of
930 superfluous "boot interrupts" cannot be disabled.
932 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
933 entry in the chipset's IO-APIC is masked (as, e.g. the RT
934 kernel does during interrupt handling). On chipsets where this
935 boot IRQ generation cannot be disabled, this workaround keeps
936 the original IRQ line masked so that only the equivalent "boot
937 IRQ" is delivered to the CPUs. The workaround also tells the
938 kernel to set up the IRQ handler on the boot IRQ line. In this
939 way only one interrupt is delivered to the kernel. Otherwise
940 the spurious second interrupt may cause the kernel to bring
941 down (vital) interrupt lines.
943 Only affects "broken" chipsets. Interrupt sharing may be
944 increased on these systems.
947 bool "Machine Check / overheating reporting"
950 Machine Check support allows the processor to notify the
951 kernel if it detects a problem (e.g. overheating, data corruption).
952 The action the kernel takes depends on the severity of the problem,
953 ranging from warning messages to halting the machine.
957 prompt "Intel MCE features"
958 depends on X86_MCE && X86_LOCAL_APIC
960 Additional support for intel specific MCE features such as
965 prompt "AMD MCE features"
966 depends on X86_MCE && X86_LOCAL_APIC
968 Additional support for AMD specific MCE features such as
969 the DRAM Error Threshold.
971 config X86_ANCIENT_MCE
972 bool "Support for old Pentium 5 / WinChip machine checks"
973 depends on X86_32 && X86_MCE
975 Include support for machine check handling on old Pentium 5 or WinChip
976 systems. These typically need to be enabled explicitly on the command
979 config X86_MCE_THRESHOLD
980 depends on X86_MCE_AMD || X86_MCE_INTEL
983 config X86_MCE_INJECT
985 tristate "Machine check injector support"
987 Provide support for injecting machine checks for testing purposes.
988 If you don't know what a machine check is and you don't do kernel
989 QA it is safe to say n.
991 config X86_THERMAL_VECTOR
993 depends on X86_MCE_INTEL
996 bool "Enable VM86 support" if EXPERT
1000 This option is required by programs like DOSEMU to run
1001 16-bit real mode legacy code on x86 processors. It also may
1002 be needed by software like XFree86 to initialize some video
1003 cards via BIOS. Disabling this option saves about 6K.
1006 bool "Enable support for 16-bit segments" if EXPERT
1009 This option is required by programs like Wine to run 16-bit
1010 protected mode legacy code on x86 processors. Disabling
1011 this option saves about 300 bytes on i386, or around 6K text
1012 plus 16K runtime memory on x86-64,
1016 depends on X86_16BIT && X86_32
1020 depends on X86_16BIT && X86_64
1022 config X86_VSYSCALL_EMULATION
1023 bool "Enable vsyscall emulation" if EXPERT
1027 This enables emulation of the legacy vsyscall page. Disabling
1028 it is roughly equivalent to booting with vsyscall=none, except
1029 that it will also disable the helpful warning if a program
1030 tries to use a vsyscall. With this option set to N, offending
1031 programs will just segfault, citing addresses of the form
1034 This option is required by many programs built before 2013, and
1035 care should be used even with newer programs if set to N.
1037 Disabling this option saves about 7K of kernel size and
1038 possibly 4K of additional runtime pagetable memory.
1041 tristate "Toshiba Laptop support"
1044 This adds a driver to safely access the System Management Mode of
1045 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1046 not work on models with a Phoenix BIOS. The System Management Mode
1047 is used to set the BIOS and power saving options on Toshiba portables.
1049 For information on utilities to make use of this driver see the
1050 Toshiba Linux utilities web site at:
1051 <http://www.buzzard.org.uk/toshiba/>.
1053 Say Y if you intend to run this kernel on a Toshiba portable.
1057 tristate "Dell laptop support"
1060 This adds a driver to safely access the System Management Mode
1061 of the CPU on the Dell Inspiron 8000. The System Management Mode
1062 is used to read cpu temperature and cooling fan status and to
1063 control the fans on the I8K portables.
1065 This driver has been tested only on the Inspiron 8000 but it may
1066 also work with other Dell laptops. You can force loading on other
1067 models by passing the parameter `force=1' to the module. Use at
1070 For information on utilities to make use of this driver see the
1071 I8K Linux utilities web site at:
1072 <http://people.debian.org/~dz/i8k/>
1074 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1077 config X86_REBOOTFIXUPS
1078 bool "Enable X86 board specific fixups for reboot"
1081 This enables chipset and/or board specific fixups to be done
1082 in order to get reboot to work correctly. This is only needed on
1083 some combinations of hardware and BIOS. The symptom, for which
1084 this config is intended, is when reboot ends with a stalled/hung
1087 Currently, the only fixup is for the Geode machines using
1088 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.
1095 tristate "CPU microcode loading support"
1096 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1100 If you say Y here, you will be able to update the microcode on
1101 certain Intel and AMD processors. The Intel support is for the
1102 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1103 Xeon etc. The AMD support is for families 0x10 and later. You will
1104 obviously need the actual microcode binary data itself which is not
1105 shipped with the Linux kernel.
1107 This option selects the general module only, you need to select
1108 at least one vendor specific module as well.
1110 To compile this driver as a module, choose M here: the module
1111 will be called microcode.
1113 config MICROCODE_INTEL
1114 bool "Intel microcode loading support"
1115 depends on MICROCODE
1119 This options enables microcode patch loading support for Intel
1122 For the current Intel microcode data package go to
1123 <https://downloadcenter.intel.com> and search for
1124 'Linux Processor Microcode Data File'.
1126 config MICROCODE_AMD
1127 bool "AMD microcode loading support"
1128 depends on MICROCODE
1131 If you select this option, microcode patch loading support for AMD
1132 processors will be enabled.
1134 config MICROCODE_OLD_INTERFACE
1136 depends on MICROCODE
1138 config MICROCODE_INTEL_EARLY
1141 config MICROCODE_AMD_EARLY
1144 config MICROCODE_EARLY
1145 bool "Early load microcode"
1146 depends on MICROCODE=y && BLK_DEV_INITRD
1147 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1148 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1151 This option provides functionality to read additional microcode data
1152 at the beginning of initrd image. The data tells kernel to load
1153 microcode to CPU's as early as possible. No functional change if no
1154 microcode data is glued to the initrd, therefore it's safe to say Y.
1157 tristate "/dev/cpu/*/msr - Model-specific register support"
1159 This device gives privileged processes access to the x86
1160 Model-Specific Registers (MSRs). It is a character device with
1161 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1162 MSR accesses are directed to a specific CPU on multi-processor
1166 tristate "/dev/cpu/*/cpuid - CPU information support"
1168 This device gives processes access to the x86 CPUID instruction to
1169 be executed on a specific processor. It is a character device
1170 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1174 prompt "High Memory Support"
1181 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1182 However, the address space of 32-bit x86 processors is only 4
1183 Gigabytes large. That means that, if you have a large amount of
1184 physical memory, not all of it can be "permanently mapped" by the
1185 kernel. The physical memory that's not permanently mapped is called
1188 If you are compiling a kernel which will never run on a machine with
1189 more than 1 Gigabyte total physical RAM, answer "off" here (default
1190 choice and suitable for most users). This will result in a "3GB/1GB"
1191 split: 3GB are mapped so that each process sees a 3GB virtual memory
1192 space and the remaining part of the 4GB virtual memory space is used
1193 by the kernel to permanently map as much physical memory as
1196 If the machine has between 1 and 4 Gigabytes physical RAM, then
1199 If more than 4 Gigabytes is used then answer "64GB" here. This
1200 selection turns Intel PAE (Physical Address Extension) mode on.
1201 PAE implements 3-level paging on IA32 processors. PAE is fully
1202 supported by Linux, PAE mode is implemented on all recent Intel
1203 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1204 then the kernel will not boot on CPUs that don't support PAE!
1206 The actual amount of total physical memory will either be
1207 auto detected or can be forced by using a kernel command line option
1208 such as "mem=256M". (Try "man bootparam" or see the documentation of
1209 your boot loader (lilo or loadlin) about how to pass options to the
1210 kernel at boot time.)
1212 If unsure, say "off".
1217 Select this if you have a 32-bit processor and between 1 and 4
1218 gigabytes of physical RAM.
1225 Select this if you have a 32-bit processor and more than 4
1226 gigabytes of physical RAM.
1231 prompt "Memory split" if EXPERT
1235 Select the desired split between kernel and user memory.
1237 If the address range available to the kernel is less than the
1238 physical memory installed, the remaining memory will be available
1239 as "high memory". Accessing high memory is a little more costly
1240 than low memory, as it needs to be mapped into the kernel first.
1241 Note that increasing the kernel address space limits the range
1242 available to user programs, making the address space there
1243 tighter. Selecting anything other than the default 3G/1G split
1244 will also likely make your kernel incompatible with binary-only
1247 If you are not absolutely sure what you are doing, leave this
1251 bool "3G/1G user/kernel split"
1252 config VMSPLIT_3G_OPT
1254 bool "3G/1G user/kernel split (for full 1G low memory)"
1256 bool "2G/2G user/kernel split"
1257 config VMSPLIT_2G_OPT
1259 bool "2G/2G user/kernel split (for full 2G low memory)"
1261 bool "1G/3G user/kernel split"
1266 default 0xB0000000 if VMSPLIT_3G_OPT
1267 default 0x80000000 if VMSPLIT_2G
1268 default 0x78000000 if VMSPLIT_2G_OPT
1269 default 0x40000000 if VMSPLIT_1G
1275 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1278 bool "PAE (Physical Address Extension) Support"
1279 depends on X86_32 && !HIGHMEM4G
1281 PAE is required for NX support, and furthermore enables
1282 larger swapspace support for non-overcommit purposes. It
1283 has the cost of more pagetable lookup overhead, and also
1284 consumes more pagetable space per process.
1286 config ARCH_PHYS_ADDR_T_64BIT
1288 depends on X86_64 || X86_PAE
1290 config ARCH_DMA_ADDR_T_64BIT
1292 depends on X86_64 || HIGHMEM64G
1294 config X86_DIRECT_GBPAGES
1296 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1298 Certain kernel features effectively disable kernel
1299 linear 1 GB mappings (even if the CPU otherwise
1300 supports them), so don't confuse the user by printing
1301 that we have them enabled.
1303 # Common NUMA Features
1305 bool "Numa Memory Allocation and Scheduler Support"
1307 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1308 default y if X86_BIGSMP
1310 Enable NUMA (Non Uniform Memory Access) support.
1312 The kernel will try to allocate memory used by a CPU on the
1313 local memory controller of the CPU and add some more
1314 NUMA awareness to the kernel.
1316 For 64-bit this is recommended if the system is Intel Core i7
1317 (or later), AMD Opteron, or EM64T NUMA.
1319 For 32-bit this is only needed if you boot a 32-bit
1320 kernel on a 64-bit NUMA platform.
1322 Otherwise, you should say N.
1326 prompt "Old style AMD Opteron NUMA detection"
1327 depends on X86_64 && NUMA && PCI
1329 Enable AMD NUMA node topology detection. You should say Y here if
1330 you have a multi processor AMD system. This uses an old method to
1331 read the NUMA configuration directly from the builtin Northbridge
1332 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1333 which also takes priority if both are compiled in.
1335 config X86_64_ACPI_NUMA
1337 prompt "ACPI NUMA detection"
1338 depends on X86_64 && NUMA && ACPI && PCI
1341 Enable ACPI SRAT based node topology detection.
1343 # Some NUMA nodes have memory ranges that span
1344 # other nodes. Even though a pfn is valid and
1345 # between a node's start and end pfns, it may not
1346 # reside on that node. See memmap_init_zone()
1348 config NODES_SPAN_OTHER_NODES
1350 depends on X86_64_ACPI_NUMA
1353 bool "NUMA emulation"
1356 Enable NUMA emulation. A flat machine will be split
1357 into virtual nodes when booted with "numa=fake=N", where N is the
1358 number of nodes. This is only useful for debugging.
1361 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1363 default "10" if MAXSMP
1364 default "6" if X86_64
1366 depends on NEED_MULTIPLE_NODES
1368 Specify the maximum number of NUMA Nodes available on the target
1369 system. Increases memory reserved to accommodate various tables.
1371 config ARCH_HAVE_MEMORY_PRESENT
1373 depends on X86_32 && DISCONTIGMEM
1375 config NEED_NODE_MEMMAP_SIZE
1377 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1379 config ARCH_FLATMEM_ENABLE
1381 depends on X86_32 && !NUMA
1383 config ARCH_DISCONTIGMEM_ENABLE
1385 depends on NUMA && X86_32
1387 config ARCH_DISCONTIGMEM_DEFAULT
1389 depends on NUMA && X86_32
1391 config ARCH_SPARSEMEM_ENABLE
1393 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1394 select SPARSEMEM_STATIC if X86_32
1395 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1397 config ARCH_SPARSEMEM_DEFAULT
1401 config ARCH_SELECT_MEMORY_MODEL
1403 depends on ARCH_SPARSEMEM_ENABLE
1405 config ARCH_MEMORY_PROBE
1406 bool "Enable sysfs memory/probe interface"
1407 depends on X86_64 && MEMORY_HOTPLUG
1409 This option enables a sysfs memory/probe interface for testing.
1410 See Documentation/memory-hotplug.txt for more information.
1411 If you are unsure how to answer this question, answer N.
1413 config ARCH_PROC_KCORE_TEXT
1415 depends on X86_64 && PROC_KCORE
1417 config ILLEGAL_POINTER_VALUE
1420 default 0xdead000000000000 if X86_64
1424 config X86_PMEM_LEGACY
1425 bool "Support non-standard NVDIMMs and ADR protected memory"
1427 Treat memory marked using the non-standard e820 type of 12 as used
1428 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1429 The kernel will offer these regions to the 'pmem' driver so
1430 they can be used for persistent storage.
1435 bool "Allocate 3rd-level pagetables from highmem"
1438 The VM uses one page table entry for each page of physical memory.
1439 For systems with a lot of RAM, this can be wasteful of precious
1440 low memory. Setting this option will put user-space page table
1441 entries in high memory.
1443 config X86_CHECK_BIOS_CORRUPTION
1444 bool "Check for low memory corruption"
1446 Periodically check for memory corruption in low memory, which
1447 is suspected to be caused by BIOS. Even when enabled in the
1448 configuration, it is disabled at runtime. Enable it by
1449 setting "memory_corruption_check=1" on the kernel command
1450 line. By default it scans the low 64k of memory every 60
1451 seconds; see the memory_corruption_check_size and
1452 memory_corruption_check_period parameters in
1453 Documentation/kernel-parameters.txt to adjust this.
1455 When enabled with the default parameters, this option has
1456 almost no overhead, as it reserves a relatively small amount
1457 of memory and scans it infrequently. It both detects corruption
1458 and prevents it from affecting the running system.
1460 It is, however, intended as a diagnostic tool; if repeatable
1461 BIOS-originated corruption always affects the same memory,
1462 you can use memmap= to prevent the kernel from using that
1465 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1466 bool "Set the default setting of memory_corruption_check"
1467 depends on X86_CHECK_BIOS_CORRUPTION
1470 Set whether the default state of memory_corruption_check is
1473 config X86_RESERVE_LOW
1474 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1478 Specify the amount of low memory to reserve for the BIOS.
1480 The first page contains BIOS data structures that the kernel
1481 must not use, so that page must always be reserved.
1483 By default we reserve the first 64K of physical RAM, as a
1484 number of BIOSes are known to corrupt that memory range
1485 during events such as suspend/resume or monitor cable
1486 insertion, so it must not be used by the kernel.
1488 You can set this to 4 if you are absolutely sure that you
1489 trust the BIOS to get all its memory reservations and usages
1490 right. If you know your BIOS have problems beyond the
1491 default 64K area, you can set this to 640 to avoid using the
1492 entire low memory range.
1494 If you have doubts about the BIOS (e.g. suspend/resume does
1495 not work or there's kernel crashes after certain hardware
1496 hotplug events) then you might want to enable
1497 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1498 typical corruption patterns.
1500 Leave this to the default value of 64 if you are unsure.
1502 config MATH_EMULATION
1504 prompt "Math emulation" if X86_32
1506 Linux can emulate a math coprocessor (used for floating point
1507 operations) if you don't have one. 486DX and Pentium processors have
1508 a math coprocessor built in, 486SX and 386 do not, unless you added
1509 a 487DX or 387, respectively. (The messages during boot time can
1510 give you some hints here ["man dmesg"].) Everyone needs either a
1511 coprocessor or this emulation.
1513 If you don't have a math coprocessor, you need to say Y here; if you
1514 say Y here even though you have a coprocessor, the coprocessor will
1515 be used nevertheless. (This behavior can be changed with the kernel
1516 command line option "no387", which comes handy if your coprocessor
1517 is broken. Try "man bootparam" or see the documentation of your boot
1518 loader (lilo or loadlin) about how to pass options to the kernel at
1519 boot time.) This means that it is a good idea to say Y here if you
1520 intend to use this kernel on different machines.
1522 More information about the internals of the Linux math coprocessor
1523 emulation can be found in <file:arch/x86/math-emu/README>.
1525 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1526 kernel, it won't hurt.
1530 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1532 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1533 the Memory Type Range Registers (MTRRs) may be used to control
1534 processor access to memory ranges. This is most useful if you have
1535 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1536 allows bus write transfers to be combined into a larger transfer
1537 before bursting over the PCI/AGP bus. This can increase performance
1538 of image write operations 2.5 times or more. Saying Y here creates a
1539 /proc/mtrr file which may be used to manipulate your processor's
1540 MTRRs. Typically the X server should use this.
1542 This code has a reasonably generic interface so that similar
1543 control registers on other processors can be easily supported
1546 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1547 Registers (ARRs) which provide a similar functionality to MTRRs. For
1548 these, the ARRs are used to emulate the MTRRs.
1549 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1550 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1551 write-combining. All of these processors are supported by this code
1552 and it makes sense to say Y here if you have one of them.
1554 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1555 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1556 can lead to all sorts of problems, so it's good to say Y here.
1558 You can safely say Y even if your machine doesn't have MTRRs, you'll
1559 just add about 9 KB to your kernel.
1561 See <file:Documentation/x86/mtrr.txt> for more information.
1563 config MTRR_SANITIZER
1565 prompt "MTRR cleanup support"
1568 Convert MTRR layout from continuous to discrete, so X drivers can
1569 add writeback entries.
1571 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1572 The largest mtrr entry size for a continuous block can be set with
1577 config MTRR_SANITIZER_ENABLE_DEFAULT
1578 int "MTRR cleanup enable value (0-1)"
1581 depends on MTRR_SANITIZER
1583 Enable mtrr cleanup default value
1585 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1586 int "MTRR cleanup spare reg num (0-7)"
1589 depends on MTRR_SANITIZER
1591 mtrr cleanup spare entries default, it can be changed via
1592 mtrr_spare_reg_nr=N on the kernel command line.
1596 prompt "x86 PAT support" if EXPERT
1599 Use PAT attributes to setup page level cache control.
1601 PATs are the modern equivalents of MTRRs and are much more
1602 flexible than MTRRs.
1604 Say N here if you see bootup problems (boot crash, boot hang,
1605 spontaneous reboots) or a non-working video driver.
1609 config ARCH_USES_PG_UNCACHED
1615 prompt "x86 architectural random number generator" if EXPERT
1617 Enable the x86 architectural RDRAND instruction
1618 (Intel Bull Mountain technology) to generate random numbers.
1619 If supported, this is a high bandwidth, cryptographically
1620 secure hardware random number generator.
1624 prompt "Supervisor Mode Access Prevention" if EXPERT
1626 Supervisor Mode Access Prevention (SMAP) is a security
1627 feature in newer Intel processors. There is a small
1628 performance cost if this enabled and turned on; there is
1629 also a small increase in the kernel size if this is enabled.
1633 config X86_INTEL_MPX
1634 prompt "Intel MPX (Memory Protection Extensions)"
1636 depends on CPU_SUP_INTEL
1638 MPX provides hardware features that can be used in
1639 conjunction with compiler-instrumented code to check
1640 memory references. It is designed to detect buffer
1641 overflow or underflow bugs.
1643 This option enables running applications which are
1644 instrumented or otherwise use MPX. It does not use MPX
1645 itself inside the kernel or to protect the kernel
1646 against bad memory references.
1648 Enabling this option will make the kernel larger:
1649 ~8k of kernel text and 36 bytes of data on a 64-bit
1650 defconfig. It adds a long to the 'mm_struct' which
1651 will increase the kernel memory overhead of each
1652 process and adds some branches to paths used during
1653 exec() and munmap().
1655 For details, see Documentation/x86/intel_mpx.txt
1660 bool "EFI runtime service support"
1663 select EFI_RUNTIME_WRAPPERS
1665 This enables the kernel to use EFI runtime services that are
1666 available (such as the EFI variable services).
1668 This option is only useful on systems that have EFI firmware.
1669 In addition, you should use the latest ELILO loader available
1670 at <http://elilo.sourceforge.net> in order to take advantage
1671 of EFI runtime services. However, even with this option, the
1672 resultant kernel should continue to boot on existing non-EFI
1676 bool "EFI stub support"
1677 depends on EFI && !X86_USE_3DNOW
1680 This kernel feature allows a bzImage to be loaded directly
1681 by EFI firmware without the use of a bootloader.
1683 See Documentation/efi-stub.txt for more information.
1686 bool "EFI mixed-mode support"
1687 depends on EFI_STUB && X86_64
1689 Enabling this feature allows a 64-bit kernel to be booted
1690 on a 32-bit firmware, provided that your CPU supports 64-bit
1693 Note that it is not possible to boot a mixed-mode enabled
1694 kernel via the EFI boot stub - a bootloader that supports
1695 the EFI handover protocol must be used.
1701 prompt "Enable seccomp to safely compute untrusted bytecode"
1703 This kernel feature is useful for number crunching applications
1704 that may need to compute untrusted bytecode during their
1705 execution. By using pipes or other transports made available to
1706 the process as file descriptors supporting the read/write
1707 syscalls, it's possible to isolate those applications in
1708 their own address space using seccomp. Once seccomp is
1709 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1710 and the task is only allowed to execute a few safe syscalls
1711 defined by each seccomp mode.
1713 If unsure, say Y. Only embedded should say N here.
1715 source kernel/Kconfig.hz
1718 bool "kexec system call"
1720 kexec is a system call that implements the ability to shutdown your
1721 current kernel, and to start another kernel. It is like a reboot
1722 but it is independent of the system firmware. And like a reboot
1723 you can start any kernel with it, not just Linux.
1725 The name comes from the similarity to the exec system call.
1727 It is an ongoing process to be certain the hardware in a machine
1728 is properly shutdown, so do not be surprised if this code does not
1729 initially work for you. As of this writing the exact hardware
1730 interface is strongly in flux, so no good recommendation can be
1734 bool "kexec file based system call"
1739 depends on CRYPTO_SHA256=y
1741 This is new version of kexec system call. This system call is
1742 file based and takes file descriptors as system call argument
1743 for kernel and initramfs as opposed to list of segments as
1744 accepted by previous system call.
1746 config KEXEC_VERIFY_SIG
1747 bool "Verify kernel signature during kexec_file_load() syscall"
1748 depends on KEXEC_FILE
1750 This option makes kernel signature verification mandatory for
1751 the kexec_file_load() syscall.
1753 In addition to that option, you need to enable signature
1754 verification for the corresponding kernel image type being
1755 loaded in order for this to work.
1757 config KEXEC_BZIMAGE_VERIFY_SIG
1758 bool "Enable bzImage signature verification support"
1759 depends on KEXEC_VERIFY_SIG
1760 depends on SIGNED_PE_FILE_VERIFICATION
1761 select SYSTEM_TRUSTED_KEYRING
1763 Enable bzImage signature verification support.
1766 bool "kernel crash dumps"
1767 depends on X86_64 || (X86_32 && HIGHMEM)
1769 Generate crash dump after being started by kexec.
1770 This should be normally only set in special crash dump kernels
1771 which are loaded in the main kernel with kexec-tools into
1772 a specially reserved region and then later executed after
1773 a crash by kdump/kexec. The crash dump kernel must be compiled
1774 to a memory address not used by the main kernel or BIOS using
1775 PHYSICAL_START, or it must be built as a relocatable image
1776 (CONFIG_RELOCATABLE=y).
1777 For more details see Documentation/kdump/kdump.txt
1781 depends on KEXEC && HIBERNATION
1783 Jump between original kernel and kexeced kernel and invoke
1784 code in physical address mode via KEXEC
1786 config PHYSICAL_START
1787 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1790 This gives the physical address where the kernel is loaded.
1792 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1793 bzImage will decompress itself to above physical address and
1794 run from there. Otherwise, bzImage will run from the address where
1795 it has been loaded by the boot loader and will ignore above physical
1798 In normal kdump cases one does not have to set/change this option
1799 as now bzImage can be compiled as a completely relocatable image
1800 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1801 address. This option is mainly useful for the folks who don't want
1802 to use a bzImage for capturing the crash dump and want to use a
1803 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1804 to be specifically compiled to run from a specific memory area
1805 (normally a reserved region) and this option comes handy.
1807 So if you are using bzImage for capturing the crash dump,
1808 leave the value here unchanged to 0x1000000 and set
1809 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1810 for capturing the crash dump change this value to start of
1811 the reserved region. In other words, it can be set based on
1812 the "X" value as specified in the "crashkernel=YM@XM"
1813 command line boot parameter passed to the panic-ed
1814 kernel. Please take a look at Documentation/kdump/kdump.txt
1815 for more details about crash dumps.
1817 Usage of bzImage for capturing the crash dump is recommended as
1818 one does not have to build two kernels. Same kernel can be used
1819 as production kernel and capture kernel. Above option should have
1820 gone away after relocatable bzImage support is introduced. But it
1821 is present because there are users out there who continue to use
1822 vmlinux for dump capture. This option should go away down the
1825 Don't change this unless you know what you are doing.
1828 bool "Build a relocatable kernel"
1831 This builds a kernel image that retains relocation information
1832 so it can be loaded someplace besides the default 1MB.
1833 The relocations tend to make the kernel binary about 10% larger,
1834 but are discarded at runtime.
1836 One use is for the kexec on panic case where the recovery kernel
1837 must live at a different physical address than the primary
1840 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1841 it has been loaded at and the compile time physical address
1842 (CONFIG_PHYSICAL_START) is used as the minimum location.
1844 config RANDOMIZE_BASE
1845 bool "Randomize the address of the kernel image"
1846 depends on RELOCATABLE
1849 Randomizes the physical and virtual address at which the
1850 kernel image is decompressed, as a security feature that
1851 deters exploit attempts relying on knowledge of the location
1852 of kernel internals.
1854 Entropy is generated using the RDRAND instruction if it is
1855 supported. If RDTSC is supported, it is used as well. If
1856 neither RDRAND nor RDTSC are supported, then randomness is
1857 read from the i8254 timer.
1859 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1860 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1861 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1862 minimum of 2MiB, only 10 bits of entropy is theoretically
1863 possible. At best, due to page table layouts, 64-bit can use
1864 9 bits of entropy and 32-bit uses 8 bits.
1868 config RANDOMIZE_BASE_MAX_OFFSET
1869 hex "Maximum kASLR offset allowed" if EXPERT
1870 depends on RANDOMIZE_BASE
1871 range 0x0 0x20000000 if X86_32
1872 default "0x20000000" if X86_32
1873 range 0x0 0x40000000 if X86_64
1874 default "0x40000000" if X86_64
1876 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1877 memory is used to determine the maximal offset in bytes that will
1878 be applied to the kernel when kernel Address Space Layout
1879 Randomization (kASLR) is active. This must be a multiple of
1882 On 32-bit this is limited to 512MiB by page table layouts. The
1885 On 64-bit this is limited by how the kernel fixmap page table is
1886 positioned, so this cannot be larger than 1GiB currently. Without
1887 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1888 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1889 modules area will shrink to compensate, up to the current maximum
1890 1GiB to 1GiB split. The default is 1GiB.
1892 If unsure, leave at the default value.
1894 # Relocation on x86 needs some additional build support
1895 config X86_NEED_RELOCS
1897 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1899 config PHYSICAL_ALIGN
1900 hex "Alignment value to which kernel should be aligned"
1902 range 0x2000 0x1000000 if X86_32
1903 range 0x200000 0x1000000 if X86_64
1905 This value puts the alignment restrictions on physical address
1906 where kernel is loaded and run from. Kernel is compiled for an
1907 address which meets above alignment restriction.
1909 If bootloader loads the kernel at a non-aligned address and
1910 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1911 address aligned to above value and run from there.
1913 If bootloader loads the kernel at a non-aligned address and
1914 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1915 load address and decompress itself to the address it has been
1916 compiled for and run from there. The address for which kernel is
1917 compiled already meets above alignment restrictions. Hence the
1918 end result is that kernel runs from a physical address meeting
1919 above alignment restrictions.
1921 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1922 this value must be a multiple of 0x200000.
1924 Don't change this unless you know what you are doing.
1927 bool "Support for hot-pluggable CPUs"
1930 Say Y here to allow turning CPUs off and on. CPUs can be
1931 controlled through /sys/devices/system/cpu.
1932 ( Note: power management support will enable this option
1933 automatically on SMP systems. )
1934 Say N if you want to disable CPU hotplug.
1936 config BOOTPARAM_HOTPLUG_CPU0
1937 bool "Set default setting of cpu0_hotpluggable"
1939 depends on HOTPLUG_CPU
1941 Set whether default state of cpu0_hotpluggable is on or off.
1943 Say Y here to enable CPU0 hotplug by default. If this switch
1944 is turned on, there is no need to give cpu0_hotplug kernel
1945 parameter and the CPU0 hotplug feature is enabled by default.
1947 Please note: there are two known CPU0 dependencies if you want
1948 to enable the CPU0 hotplug feature either by this switch or by
1949 cpu0_hotplug kernel parameter.
1951 First, resume from hibernate or suspend always starts from CPU0.
1952 So hibernate and suspend are prevented if CPU0 is offline.
1954 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1955 offline if any interrupt can not migrate out of CPU0. There may
1956 be other CPU0 dependencies.
1958 Please make sure the dependencies are under your control before
1959 you enable this feature.
1961 Say N if you don't want to enable CPU0 hotplug feature by default.
1962 You still can enable the CPU0 hotplug feature at boot by kernel
1963 parameter cpu0_hotplug.
1965 config DEBUG_HOTPLUG_CPU0
1967 prompt "Debug CPU0 hotplug"
1968 depends on HOTPLUG_CPU
1970 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1971 soon as possible and boots up userspace with CPU0 offlined. User
1972 can online CPU0 back after boot time.
1974 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1975 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1976 compilation or giving cpu0_hotplug kernel parameter at boot.
1982 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1983 depends on X86_32 || IA32_EMULATION
1985 Certain buggy versions of glibc will crash if they are
1986 presented with a 32-bit vDSO that is not mapped at the address
1987 indicated in its segment table.
1989 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1990 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1991 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
1992 the only released version with the bug, but OpenSUSE 9
1993 contains a buggy "glibc 2.3.2".
1995 The symptom of the bug is that everything crashes on startup, saying:
1996 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1998 Saying Y here changes the default value of the vdso32 boot
1999 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2000 This works around the glibc bug but hurts performance.
2002 If unsure, say N: if you are compiling your own kernel, you
2003 are unlikely to be using a buggy version of glibc.
2006 bool "Built-in kernel command line"
2008 Allow for specifying boot arguments to the kernel at
2009 build time. On some systems (e.g. embedded ones), it is
2010 necessary or convenient to provide some or all of the
2011 kernel boot arguments with the kernel itself (that is,
2012 to not rely on the boot loader to provide them.)
2014 To compile command line arguments into the kernel,
2015 set this option to 'Y', then fill in the
2016 the boot arguments in CONFIG_CMDLINE.
2018 Systems with fully functional boot loaders (i.e. non-embedded)
2019 should leave this option set to 'N'.
2022 string "Built-in kernel command string"
2023 depends on CMDLINE_BOOL
2026 Enter arguments here that should be compiled into the kernel
2027 image and used at boot time. If the boot loader provides a
2028 command line at boot time, it is appended to this string to
2029 form the full kernel command line, when the system boots.
2031 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2032 change this behavior.
2034 In most cases, the command line (whether built-in or provided
2035 by the boot loader) should specify the device for the root
2038 config CMDLINE_OVERRIDE
2039 bool "Built-in command line overrides boot loader arguments"
2040 depends on CMDLINE_BOOL
2042 Set this option to 'Y' to have the kernel ignore the boot loader
2043 command line, and use ONLY the built-in command line.
2045 This is used to work around broken boot loaders. This should
2046 be set to 'N' under normal conditions.
2048 source "kernel/livepatch/Kconfig"
2052 config ARCH_ENABLE_MEMORY_HOTPLUG
2054 depends on X86_64 || (X86_32 && HIGHMEM)
2056 config ARCH_ENABLE_MEMORY_HOTREMOVE
2058 depends on MEMORY_HOTPLUG
2060 config USE_PERCPU_NUMA_NODE_ID
2064 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2066 depends on X86_64 || X86_PAE
2068 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2070 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2072 menu "Power management and ACPI options"
2074 config ARCH_HIBERNATION_HEADER
2076 depends on X86_64 && HIBERNATION
2078 source "kernel/power/Kconfig"
2080 source "drivers/acpi/Kconfig"
2082 source "drivers/sfi/Kconfig"
2089 tristate "APM (Advanced Power Management) BIOS support"
2090 depends on X86_32 && PM_SLEEP
2092 APM is a BIOS specification for saving power using several different
2093 techniques. This is mostly useful for battery powered laptops with
2094 APM compliant BIOSes. If you say Y here, the system time will be
2095 reset after a RESUME operation, the /proc/apm device will provide
2096 battery status information, and user-space programs will receive
2097 notification of APM "events" (e.g. battery status change).
2099 If you select "Y" here, you can disable actual use of the APM
2100 BIOS by passing the "apm=off" option to the kernel at boot time.
2102 Note that the APM support is almost completely disabled for
2103 machines with more than one CPU.
2105 In order to use APM, you will need supporting software. For location
2106 and more information, read <file:Documentation/power/apm-acpi.txt>
2107 and the Battery Powered Linux mini-HOWTO, available from
2108 <http://www.tldp.org/docs.html#howto>.
2110 This driver does not spin down disk drives (see the hdparm(8)
2111 manpage ("man 8 hdparm") for that), and it doesn't turn off
2112 VESA-compliant "green" monitors.
2114 This driver does not support the TI 4000M TravelMate and the ACER
2115 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2116 desktop machines also don't have compliant BIOSes, and this driver
2117 may cause those machines to panic during the boot phase.
2119 Generally, if you don't have a battery in your machine, there isn't
2120 much point in using this driver and you should say N. If you get
2121 random kernel OOPSes or reboots that don't seem to be related to
2122 anything, try disabling/enabling this option (or disabling/enabling
2125 Some other things you should try when experiencing seemingly random,
2128 1) make sure that you have enough swap space and that it is
2130 2) pass the "no-hlt" option to the kernel
2131 3) switch on floating point emulation in the kernel and pass
2132 the "no387" option to the kernel
2133 4) pass the "floppy=nodma" option to the kernel
2134 5) pass the "mem=4M" option to the kernel (thereby disabling
2135 all but the first 4 MB of RAM)
2136 6) make sure that the CPU is not over clocked.
2137 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2138 8) disable the cache from your BIOS settings
2139 9) install a fan for the video card or exchange video RAM
2140 10) install a better fan for the CPU
2141 11) exchange RAM chips
2142 12) exchange the motherboard.
2144 To compile this driver as a module, choose M here: the
2145 module will be called apm.
2149 config APM_IGNORE_USER_SUSPEND
2150 bool "Ignore USER SUSPEND"
2152 This option will ignore USER SUSPEND requests. On machines with a
2153 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2154 series notebooks, it is necessary to say Y because of a BIOS bug.
2156 config APM_DO_ENABLE
2157 bool "Enable PM at boot time"
2159 Enable APM features at boot time. From page 36 of the APM BIOS
2160 specification: "When disabled, the APM BIOS does not automatically
2161 power manage devices, enter the Standby State, enter the Suspend
2162 State, or take power saving steps in response to CPU Idle calls."
2163 This driver will make CPU Idle calls when Linux is idle (unless this
2164 feature is turned off -- see "Do CPU IDLE calls", below). This
2165 should always save battery power, but more complicated APM features
2166 will be dependent on your BIOS implementation. You may need to turn
2167 this option off if your computer hangs at boot time when using APM
2168 support, or if it beeps continuously instead of suspending. Turn
2169 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2170 T400CDT. This is off by default since most machines do fine without
2175 bool "Make CPU Idle calls when idle"
2177 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2178 On some machines, this can activate improved power savings, such as
2179 a slowed CPU clock rate, when the machine is idle. These idle calls
2180 are made after the idle loop has run for some length of time (e.g.,
2181 333 mS). On some machines, this will cause a hang at boot time or
2182 whenever the CPU becomes idle. (On machines with more than one CPU,
2183 this option does nothing.)
2185 config APM_DISPLAY_BLANK
2186 bool "Enable console blanking using APM"
2188 Enable console blanking using the APM. Some laptops can use this to
2189 turn off the LCD backlight when the screen blanker of the Linux
2190 virtual console blanks the screen. Note that this is only used by
2191 the virtual console screen blanker, and won't turn off the backlight
2192 when using the X Window system. This also doesn't have anything to
2193 do with your VESA-compliant power-saving monitor. Further, this
2194 option doesn't work for all laptops -- it might not turn off your
2195 backlight at all, or it might print a lot of errors to the console,
2196 especially if you are using gpm.
2198 config APM_ALLOW_INTS
2199 bool "Allow interrupts during APM BIOS calls"
2201 Normally we disable external interrupts while we are making calls to
2202 the APM BIOS as a measure to lessen the effects of a badly behaving
2203 BIOS implementation. The BIOS should reenable interrupts if it
2204 needs to. Unfortunately, some BIOSes do not -- especially those in
2205 many of the newer IBM Thinkpads. If you experience hangs when you
2206 suspend, try setting this to Y. Otherwise, say N.
2210 source "drivers/cpufreq/Kconfig"
2212 source "drivers/cpuidle/Kconfig"
2214 source "drivers/idle/Kconfig"
2219 menu "Bus options (PCI etc.)"
2225 Find out whether you have a PCI motherboard. PCI is the name of a
2226 bus system, i.e. the way the CPU talks to the other stuff inside
2227 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2228 VESA. If you have PCI, say Y, otherwise N.
2231 prompt "PCI access mode"
2232 depends on X86_32 && PCI
2235 On PCI systems, the BIOS can be used to detect the PCI devices and
2236 determine their configuration. However, some old PCI motherboards
2237 have BIOS bugs and may crash if this is done. Also, some embedded
2238 PCI-based systems don't have any BIOS at all. Linux can also try to
2239 detect the PCI hardware directly without using the BIOS.
2241 With this option, you can specify how Linux should detect the
2242 PCI devices. If you choose "BIOS", the BIOS will be used,
2243 if you choose "Direct", the BIOS won't be used, and if you
2244 choose "MMConfig", then PCI Express MMCONFIG will be used.
2245 If you choose "Any", the kernel will try MMCONFIG, then the
2246 direct access method and falls back to the BIOS if that doesn't
2247 work. If unsure, go with the default, which is "Any".
2252 config PCI_GOMMCONFIG
2269 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2271 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2274 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2278 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2282 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2286 depends on PCI && XEN
2294 bool "Support mmconfig PCI config space access"
2295 depends on X86_64 && PCI && ACPI
2297 config PCI_CNB20LE_QUIRK
2298 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2301 Read the PCI windows out of the CNB20LE host bridge. This allows
2302 PCI hotplug to work on systems with the CNB20LE chipset which do
2305 There's no public spec for this chipset, and this functionality
2306 is known to be incomplete.
2308 You should say N unless you know you need this.
2310 source "drivers/pci/pcie/Kconfig"
2312 source "drivers/pci/Kconfig"
2314 # x86_64 have no ISA slots, but can have ISA-style DMA.
2316 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2319 Enables ISA-style DMA support for devices requiring such controllers.
2327 Find out whether you have ISA slots on your motherboard. ISA is the
2328 name of a bus system, i.e. the way the CPU talks to the other stuff
2329 inside your box. Other bus systems are PCI, EISA, MicroChannel
2330 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2331 newer boards don't support it. If you have ISA, say Y, otherwise N.
2337 The Extended Industry Standard Architecture (EISA) bus was
2338 developed as an open alternative to the IBM MicroChannel bus.
2340 The EISA bus provided some of the features of the IBM MicroChannel
2341 bus while maintaining backward compatibility with cards made for
2342 the older ISA bus. The EISA bus saw limited use between 1988 and
2343 1995 when it was made obsolete by the PCI bus.
2345 Say Y here if you are building a kernel for an EISA-based machine.
2349 source "drivers/eisa/Kconfig"
2352 tristate "NatSemi SCx200 support"
2354 This provides basic support for National Semiconductor's
2355 (now AMD's) Geode processors. The driver probes for the
2356 PCI-IDs of several on-chip devices, so its a good dependency
2357 for other scx200_* drivers.
2359 If compiled as a module, the driver is named scx200.
2361 config SCx200HR_TIMER
2362 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2366 This driver provides a clocksource built upon the on-chip
2367 27MHz high-resolution timer. Its also a workaround for
2368 NSC Geode SC-1100's buggy TSC, which loses time when the
2369 processor goes idle (as is done by the scheduler). The
2370 other workaround is idle=poll boot option.
2373 bool "One Laptop Per Child support"
2380 Add support for detecting the unique features of the OLPC
2384 bool "OLPC XO-1 Power Management"
2385 depends on OLPC && MFD_CS5535 && PM_SLEEP
2388 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2391 bool "OLPC XO-1 Real Time Clock"
2392 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2394 Add support for the XO-1 real time clock, which can be used as a
2395 programmable wakeup source.
2398 bool "OLPC XO-1 SCI extras"
2399 depends on OLPC && OLPC_XO1_PM
2405 Add support for SCI-based features of the OLPC XO-1 laptop:
2406 - EC-driven system wakeups
2410 - AC adapter status updates
2411 - Battery status updates
2413 config OLPC_XO15_SCI
2414 bool "OLPC XO-1.5 SCI extras"
2415 depends on OLPC && ACPI
2418 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2419 - EC-driven system wakeups
2420 - AC adapter status updates
2421 - Battery status updates
2424 bool "PCEngines ALIX System Support (LED setup)"
2427 This option enables system support for the PCEngines ALIX.
2428 At present this just sets up LEDs for GPIO control on
2429 ALIX2/3/6 boards. However, other system specific setup should
2432 Note: You must still enable the drivers for GPIO and LED support
2433 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2435 Note: You have to set alix.force=1 for boards with Award BIOS.
2438 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2441 This option enables system support for the Soekris Engineering net5501.
2444 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2448 This option enables system support for the Traverse Technologies GEOS.
2451 bool "Technologic Systems TS-5500 platform support"
2453 select CHECK_SIGNATURE
2457 This option enables system support for the Technologic Systems TS-5500.
2463 depends on CPU_SUP_AMD && PCI
2465 source "drivers/pcmcia/Kconfig"
2467 source "drivers/pci/hotplug/Kconfig"
2470 tristate "RapidIO support"
2474 If enabled this option will include drivers and the core
2475 infrastructure code to support RapidIO interconnect devices.
2477 source "drivers/rapidio/Kconfig"
2480 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2482 Firmwares often provide initial graphics framebuffers so the BIOS,
2483 bootloader or kernel can show basic video-output during boot for
2484 user-guidance and debugging. Historically, x86 used the VESA BIOS
2485 Extensions and EFI-framebuffers for this, which are mostly limited
2487 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2488 framebuffers so the new generic system-framebuffer drivers can be
2489 used on x86. If the framebuffer is not compatible with the generic
2490 modes, it is adverticed as fallback platform framebuffer so legacy
2491 drivers like efifb, vesafb and uvesafb can pick it up.
2492 If this option is not selected, all system framebuffers are always
2493 marked as fallback platform framebuffers as usual.
2495 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2496 not be able to pick up generic system framebuffers if this option
2497 is selected. You are highly encouraged to enable simplefb as
2498 replacement if you select this option. simplefb can correctly deal
2499 with generic system framebuffers. But you should still keep vesafb
2500 and others enabled as fallback if a system framebuffer is
2501 incompatible with simplefb.
2508 menu "Executable file formats / Emulations"
2510 source "fs/Kconfig.binfmt"
2512 config IA32_EMULATION
2513 bool "IA32 Emulation"
2516 select COMPAT_BINFMT_ELF
2519 Include code to run legacy 32-bit programs under a
2520 64-bit kernel. You should likely turn this on, unless you're
2521 100% sure that you don't have any 32-bit programs left.
2524 tristate "IA32 a.out support"
2525 depends on IA32_EMULATION
2527 Support old a.out binaries in the 32bit emulation.
2530 bool "x32 ABI for 64-bit mode"
2531 depends on X86_64 && IA32_EMULATION
2533 Include code to run binaries for the x32 native 32-bit ABI
2534 for 64-bit processors. An x32 process gets access to the
2535 full 64-bit register file and wide data path while leaving
2536 pointers at 32 bits for smaller memory footprint.
2538 You will need a recent binutils (2.22 or later) with
2539 elf32_x86_64 support enabled to compile a kernel with this
2544 depends on IA32_EMULATION || X86_X32
2545 select ARCH_WANT_OLD_COMPAT_IPC
2548 config COMPAT_FOR_U64_ALIGNMENT
2551 config SYSVIPC_COMPAT
2563 config HAVE_ATOMIC_IOMAP
2567 config X86_DEV_DMA_OPS
2569 depends on X86_64 || STA2X11
2571 config X86_DMA_REMAP
2579 source "net/Kconfig"
2581 source "drivers/Kconfig"
2583 source "drivers/firmware/Kconfig"
2587 source "arch/x86/Kconfig.debug"
2589 source "security/Kconfig"
2591 source "crypto/Kconfig"
2593 source "arch/x86/kvm/Kconfig"
2595 source "lib/Kconfig"
projects / linux-2.6-block.git / blob