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
24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
25 select HAVE_AOUT if X86_32
26 select HAVE_UNSTABLE_SCHED_CLOCK
27 select ARCH_SUPPORTS_NUMA_BALANCING
28 select ARCH_WANTS_PROT_NUMA_PROT_NONE
31 select HAVE_PCSPKR_PLATFORM
32 select HAVE_PERF_EVENTS
33 select HAVE_IOREMAP_PROT
36 select HAVE_MEMBLOCK_NODE_MAP
37 select ARCH_DISCARD_MEMBLOCK
38 select ARCH_WANT_OPTIONAL_GPIOLIB
39 select ARCH_WANT_FRAME_POINTERS
41 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
42 select HAVE_KRETPROBES
44 select HAVE_KPROBES_ON_FTRACE
45 select HAVE_FTRACE_MCOUNT_RECORD
46 select HAVE_FENTRY if X86_64
47 select HAVE_C_RECORDMCOUNT
48 select HAVE_DYNAMIC_FTRACE
49 select HAVE_DYNAMIC_FTRACE_WITH_REGS
50 select HAVE_FUNCTION_TRACER
51 select HAVE_FUNCTION_GRAPH_TRACER
52 select HAVE_FUNCTION_GRAPH_FP_TEST
53 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
54 select HAVE_SYSCALL_TRACEPOINTS
55 select SYSCTL_EXCEPTION_TRACE
58 select HAVE_ARCH_TRACEHOOK
59 select HAVE_GENERIC_DMA_COHERENT if X86_32
60 select HAVE_EFFICIENT_UNALIGNED_ACCESS
61 select USER_STACKTRACE_SUPPORT
62 select HAVE_REGS_AND_STACK_ACCESS_API
63 select HAVE_DMA_API_DEBUG
64 select HAVE_KERNEL_GZIP
65 select HAVE_KERNEL_BZIP2
66 select HAVE_KERNEL_LZMA
68 select HAVE_KERNEL_LZO
69 select HAVE_KERNEL_LZ4
70 select HAVE_HW_BREAKPOINT
71 select HAVE_MIXED_BREAKPOINTS_REGS
73 select HAVE_PERF_EVENTS_NMI
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_DEBUG_KMEMLEAK
78 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
79 select HAVE_CMPXCHG_LOCAL
80 select HAVE_CMPXCHG_DOUBLE
81 select HAVE_ARCH_KMEMCHECK
82 select HAVE_USER_RETURN_NOTIFIER
83 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
84 select HAVE_ARCH_JUMP_LABEL
85 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
87 select GENERIC_FIND_FIRST_BIT
88 select GENERIC_IRQ_PROBE
89 select GENERIC_PENDING_IRQ if SMP
90 select GENERIC_IRQ_SHOW
91 select GENERIC_CLOCKEVENTS_MIN_ADJUST
92 select IRQ_FORCED_THREADING
93 select USE_GENERIC_SMP_HELPERS if SMP
94 select HAVE_BPF_JIT if X86_64
95 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
97 select ARCH_HAVE_NMI_SAFE_CMPXCHG
99 select DCACHE_WORD_ACCESS
100 select GENERIC_SMP_IDLE_THREAD
101 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
102 select HAVE_ARCH_SECCOMP_FILTER
103 select BUILDTIME_EXTABLE_SORT
104 select GENERIC_CMOS_UPDATE
105 select HAVE_ARCH_SOFT_DIRTY
106 select CLOCKSOURCE_WATCHDOG
107 select GENERIC_CLOCKEVENTS
108 select ARCH_CLOCKSOURCE_DATA if X86_64
109 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
110 select GENERIC_TIME_VSYSCALL if X86_64
111 select KTIME_SCALAR if X86_32
112 select GENERIC_STRNCPY_FROM_USER
113 select GENERIC_STRNLEN_USER
114 select HAVE_CONTEXT_TRACKING if X86_64
115 select HAVE_IRQ_TIME_ACCOUNTING
117 select MODULES_USE_ELF_REL if X86_32
118 select MODULES_USE_ELF_RELA if X86_64
119 select CLONE_BACKWARDS if X86_32
120 select ARCH_USE_BUILTIN_BSWAP
121 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
122 select OLD_SIGACTION if X86_32
123 select COMPAT_OLD_SIGACTION if IA32_EMULATION
125 select HAVE_DEBUG_STACKOVERFLOW
127 config INSTRUCTION_DECODER
129 depends on KPROBES || PERF_EVENTS || UPROBES
133 default "elf32-i386" if X86_32
134 default "elf64-x86-64" if X86_64
136 config ARCH_DEFCONFIG
138 default "arch/x86/configs/i386_defconfig" if X86_32
139 default "arch/x86/configs/x86_64_defconfig" if X86_64
141 config LOCKDEP_SUPPORT
144 config STACKTRACE_SUPPORT
147 config HAVE_LATENCYTOP_SUPPORT
156 config NEED_DMA_MAP_STATE
158 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
160 config NEED_SG_DMA_LENGTH
163 config GENERIC_ISA_DMA
165 depends on ISA_DMA_API
170 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
172 config GENERIC_BUG_RELATIVE_POINTERS
175 config GENERIC_HWEIGHT
178 config ARCH_MAY_HAVE_PC_FDC
180 depends on ISA_DMA_API
182 config RWSEM_XCHGADD_ALGORITHM
185 config GENERIC_CALIBRATE_DELAY
188 config ARCH_HAS_CPU_RELAX
191 config ARCH_HAS_CACHE_LINE_SIZE
194 config ARCH_HAS_CPU_AUTOPROBE
197 config HAVE_SETUP_PER_CPU_AREA
200 config NEED_PER_CPU_EMBED_FIRST_CHUNK
203 config NEED_PER_CPU_PAGE_FIRST_CHUNK
206 config ARCH_HIBERNATION_POSSIBLE
209 config ARCH_SUSPEND_POSSIBLE
212 config ARCH_WANT_HUGE_PMD_SHARE
215 config ARCH_WANT_GENERAL_HUGETLB
226 config ARCH_SUPPORTS_OPTIMIZED_INLINING
229 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
232 config HAVE_INTEL_TXT
234 depends on INTEL_IOMMU && ACPI
238 depends on X86_32 && SMP
242 depends on X86_64 && SMP
248 config X86_32_LAZY_GS
250 depends on X86_32 && !CC_STACKPROTECTOR
252 config ARCH_HWEIGHT_CFLAGS
254 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
255 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
257 config ARCH_SUPPORTS_UPROBES
260 source "init/Kconfig"
261 source "kernel/Kconfig.freezer"
263 menu "Processor type and features"
266 bool "DMA memory allocation support" if EXPERT
269 DMA memory allocation support allows devices with less than 32-bit
270 addressing to allocate within the first 16MB of address space.
271 Disable if no such devices will be used.
276 bool "Symmetric multi-processing support"
278 This enables support for systems with more than one CPU. If you have
279 a system with only one CPU, like most personal computers, say N. If
280 you have a system with more than one CPU, say Y.
282 If you say N here, the kernel will run on single and multiprocessor
283 machines, but will use only one CPU of a multiprocessor machine. If
284 you say Y here, the kernel will run on many, but not all,
285 singleprocessor machines. On a singleprocessor machine, the kernel
286 will run faster if you say N here.
288 Note that if you say Y here and choose architecture "586" or
289 "Pentium" under "Processor family", the kernel will not work on 486
290 architectures. Similarly, multiprocessor kernels for the "PPro"
291 architecture may not work on all Pentium based boards.
293 People using multiprocessor machines who say Y here should also say
294 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
295 Management" code will be disabled if you say Y here.
297 See also <file:Documentation/x86/i386/IO-APIC.txt>,
298 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
299 <http://www.tldp.org/docs.html#howto>.
301 If you don't know what to do here, say N.
304 bool "Support x2apic"
305 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
307 This enables x2apic support on CPUs that have this feature.
309 This allows 32-bit apic IDs (so it can support very large systems),
310 and accesses the local apic via MSRs not via mmio.
312 If you don't know what to do here, say N.
315 bool "Enable MPS table" if ACPI || SFI
317 depends on X86_LOCAL_APIC
319 For old smp systems that do not have proper acpi support. Newer systems
320 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
323 bool "Support for big SMP systems with more than 8 CPUs"
324 depends on X86_32 && SMP
326 This option is needed for the systems that have more than 8 CPUs
330 depends on X86_GOLDFISH
333 config X86_EXTENDED_PLATFORM
334 bool "Support for extended (non-PC) x86 platforms"
337 If you disable this option then the kernel will only support
338 standard PC platforms. (which covers the vast majority of
341 If you enable this option then you'll be able to select support
342 for the following (non-PC) 32 bit x86 platforms:
343 Goldfish (Android emulator)
347 SGI 320/540 (Visual Workstation)
348 STA2X11-based (e.g. Northville)
349 Summit/EXA (IBM x440)
350 Unisys ES7000 IA32 series
351 Moorestown MID devices
353 If you have one of these systems, or if you want to build a
354 generic distribution kernel, say Y here - otherwise say N.
358 config X86_EXTENDED_PLATFORM
359 bool "Support for extended (non-PC) x86 platforms"
362 If you disable this option then the kernel will only support
363 standard PC platforms. (which covers the vast majority of
366 If you enable this option then you'll be able to select support
367 for the following (non-PC) 64 bit x86 platforms:
372 If you have one of these systems, or if you want to build a
373 generic distribution kernel, say Y here - otherwise say N.
375 # This is an alphabetically sorted list of 64 bit extended platforms
376 # Please maintain the alphabetic order if and when there are additions
378 bool "Numascale NumaChip"
380 depends on X86_EXTENDED_PLATFORM
383 depends on X86_X2APIC
384 depends on PCI_MMCONFIG
386 Adds support for Numascale NumaChip large-SMP systems. Needed to
387 enable more than ~168 cores.
388 If you don't have one of these, you should say N here.
392 select HYPERVISOR_GUEST
394 depends on X86_64 && PCI
395 depends on X86_EXTENDED_PLATFORM
398 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
399 supposed to run on these EM64T-based machines. Only choose this option
400 if you have one of these machines.
403 bool "SGI Ultraviolet"
405 depends on X86_EXTENDED_PLATFORM
407 depends on X86_X2APIC
409 This option is needed in order to support SGI Ultraviolet systems.
410 If you don't have one of these, you should say N here.
412 # Following is an alphabetically sorted list of 32 bit extended platforms
413 # Please maintain the alphabetic order if and when there are additions
416 bool "Goldfish (Virtual Platform)"
418 depends on X86_EXTENDED_PLATFORM
420 Enable support for the Goldfish virtual platform used primarily
421 for Android development. Unless you are building for the Android
422 Goldfish emulator say N here.
425 bool "CE4100 TV platform"
427 depends on PCI_GODIRECT
429 depends on X86_EXTENDED_PLATFORM
430 select X86_REBOOTFIXUPS
432 select OF_EARLY_FLATTREE
435 Select for the Intel CE media processor (CE4100) SOC.
436 This option compiles in support for the CE4100 SOC for settop
437 boxes and media devices.
439 config X86_WANT_INTEL_MID
440 bool "Intel MID platform support"
442 depends on X86_EXTENDED_PLATFORM
444 Select to build a kernel capable of supporting Intel MID platform
445 systems which do not have the PCI legacy interfaces (Moorestown,
446 Medfield). If you are building for a PC class system say N here.
448 if X86_WANT_INTEL_MID
454 bool "Medfield MID platform"
457 depends on X86_IO_APIC
465 select X86_PLATFORM_DEVICES
466 select MFD_INTEL_MSIC
468 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
469 Internet Device(MID) platform.
470 Unlike standard x86 PCs, Medfield does not have many legacy devices
471 nor standard legacy replacement devices/features. e.g. Medfield does
472 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
476 config X86_INTEL_LPSS
477 bool "Intel Low Power Subsystem Support"
482 Select to build support for Intel Low Power Subsystem such as
483 found on Intel Lynxpoint PCH. Selecting this option enables
484 things like clock tree (common clock framework) and pincontrol
485 which are needed by the LPSS peripheral drivers.
488 bool "RDC R-321x SoC"
490 depends on X86_EXTENDED_PLATFORM
492 select X86_REBOOTFIXUPS
494 This option is needed for RDC R-321x system-on-chip, also known
496 If you don't have one of these chips, you should say N here.
498 config X86_32_NON_STANDARD
499 bool "Support non-standard 32-bit SMP architectures"
500 depends on X86_32 && SMP
501 depends on X86_EXTENDED_PLATFORM
503 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
504 STA2X11, default subarchitectures. It is intended for a generic
505 binary kernel. If you select them all, kernel will probe it
506 one by one and will fallback to default.
508 # Alphabetically sorted list of Non standard 32 bit platforms
511 bool "NUMAQ (IBM/Sequent)"
512 depends on X86_32_NON_STANDARD
517 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
518 NUMA multiquad box. This changes the way that processors are
519 bootstrapped, and uses Clustered Logical APIC addressing mode instead
520 of Flat Logical. You will need a new lynxer.elf file to flash your
521 firmware with - send email to <Martin.Bligh@us.ibm.com>.
523 config X86_SUPPORTS_MEMORY_FAILURE
525 # MCE code calls memory_failure():
527 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
528 depends on !X86_NUMAQ
529 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
530 depends on X86_64 || !SPARSEMEM
531 select ARCH_SUPPORTS_MEMORY_FAILURE
534 bool "SGI 320/540 (Visual Workstation)"
535 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
536 depends on X86_32_NON_STANDARD
538 The SGI Visual Workstation series is an IA32-based workstation
539 based on SGI systems chips with some legacy PC hardware attached.
541 Say Y here to create a kernel to run on the SGI 320 or 540.
543 A kernel compiled for the Visual Workstation will run on general
544 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
547 bool "STA2X11 Companion Chip Support"
548 depends on X86_32_NON_STANDARD && PCI
549 select X86_DEV_DMA_OPS
553 select ARCH_REQUIRE_GPIOLIB
556 This adds support for boards based on the STA2X11 IO-Hub,
557 a.k.a. "ConneXt". The chip is used in place of the standard
558 PC chipset, so all "standard" peripherals are missing. If this
559 option is selected the kernel will still be able to boot on
560 standard PC machines.
563 bool "Summit/EXA (IBM x440)"
564 depends on X86_32_NON_STANDARD
566 This option is needed for IBM systems that use the Summit/EXA chipset.
567 In particular, it is needed for the x440.
570 bool "Unisys ES7000 IA32 series"
571 depends on X86_32_NON_STANDARD && X86_BIGSMP
573 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
574 supposed to run on an IA32-based Unisys ES7000 system.
577 tristate "Eurobraille/Iris poweroff module"
580 The Iris machines from EuroBraille do not have APM or ACPI support
581 to shut themselves down properly. A special I/O sequence is
582 needed to do so, which is what this module does at
585 This is only for Iris machines from EuroBraille.
589 config SCHED_OMIT_FRAME_POINTER
591 prompt "Single-depth WCHAN output"
594 Calculate simpler /proc/<PID>/wchan values. If this option
595 is disabled then wchan values will recurse back to the
596 caller function. This provides more accurate wchan values,
597 at the expense of slightly more scheduling overhead.
599 If in doubt, say "Y".
601 menuconfig HYPERVISOR_GUEST
602 bool "Linux guest support"
604 Say Y here to enable options for running Linux under various hyper-
605 visors. This option enables basic hypervisor detection and platform
608 If you say N, all options in this submenu will be skipped and
609 disabled, and Linux guest support won't be built in.
614 bool "Enable paravirtualization code"
616 This changes the kernel so it can modify itself when it is run
617 under a hypervisor, potentially improving performance significantly
618 over full virtualization. However, when run without a hypervisor
619 the kernel is theoretically slower and slightly larger.
621 config PARAVIRT_DEBUG
622 bool "paravirt-ops debugging"
623 depends on PARAVIRT && DEBUG_KERNEL
625 Enable to debug paravirt_ops internals. Specifically, BUG if
626 a paravirt_op is missing when it is called.
628 config PARAVIRT_SPINLOCKS
629 bool "Paravirtualization layer for spinlocks"
630 depends on PARAVIRT && SMP
631 select UNINLINE_SPIN_UNLOCK
633 Paravirtualized spinlocks allow a pvops backend to replace the
634 spinlock implementation with something virtualization-friendly
635 (for example, block the virtual CPU rather than spinning).
637 Unfortunately the downside is an up to 5% performance hit on
638 native kernels, with various workloads.
640 If you are unsure how to answer this question, answer N.
642 source "arch/x86/xen/Kconfig"
645 bool "KVM Guest support (including kvmclock)"
647 select PARAVIRT_CLOCK
650 This option enables various optimizations for running under the KVM
651 hypervisor. It includes a paravirtualized clock, so that instead
652 of relying on a PIT (or probably other) emulation by the
653 underlying device model, the host provides the guest with
654 timing infrastructure such as time of day, and system time
657 bool "Enable debug information for KVM Guests in debugfs"
658 depends on KVM_GUEST && DEBUG_FS
661 This option enables collection of various statistics for KVM guest.
662 Statistics are displayed in debugfs filesystem. Enabling this option
663 may incur significant overhead.
665 source "arch/x86/lguest/Kconfig"
667 config PARAVIRT_TIME_ACCOUNTING
668 bool "Paravirtual steal time accounting"
672 Select this option to enable fine granularity task steal time
673 accounting. Time spent executing other tasks in parallel with
674 the current vCPU is discounted from the vCPU power. To account for
675 that, there can be a small performance impact.
677 If in doubt, say N here.
679 config PARAVIRT_CLOCK
682 endif #HYPERVISOR_GUEST
690 This option adds a kernel parameter 'memtest', which allows memtest
692 memtest=0, mean disabled; -- default
693 memtest=1, mean do 1 test pattern;
695 memtest=4, mean do 4 test patterns.
696 If you are unsure how to answer this question, answer N.
698 config X86_SUMMIT_NUMA
700 depends on X86_32 && NUMA && X86_32_NON_STANDARD
702 config X86_CYCLONE_TIMER
704 depends on X86_SUMMIT
706 source "arch/x86/Kconfig.cpu"
710 prompt "HPET Timer Support" if X86_32
712 Use the IA-PC HPET (High Precision Event Timer) to manage
713 time in preference to the PIT and RTC, if a HPET is
715 HPET is the next generation timer replacing legacy 8254s.
716 The HPET provides a stable time base on SMP
717 systems, unlike the TSC, but it is more expensive to access,
718 as it is off-chip. You can find the HPET spec at
719 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
721 You can safely choose Y here. However, HPET will only be
722 activated if the platform and the BIOS support this feature.
723 Otherwise the 8254 will be used for timing services.
725 Choose N to continue using the legacy 8254 timer.
727 config HPET_EMULATE_RTC
729 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
732 def_bool y if X86_INTEL_MID
733 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
735 depends on X86_INTEL_MID && SFI
737 APB timer is the replacement for 8254, HPET on X86 MID platforms.
738 The APBT provides a stable time base on SMP
739 systems, unlike the TSC, but it is more expensive to access,
740 as it is off-chip. APB timers are always running regardless of CPU
741 C states, they are used as per CPU clockevent device when possible.
743 # Mark as expert because too many people got it wrong.
744 # The code disables itself when not needed.
747 bool "Enable DMI scanning" if EXPERT
749 Enabled scanning of DMI to identify machine quirks. Say Y
750 here unless you have verified that your setup is not
751 affected by entries in the DMI blacklist. Required by PNP
755 bool "GART IOMMU support" if EXPERT
758 depends on X86_64 && PCI && AMD_NB
760 Support for full DMA access of devices with 32bit memory access only
761 on systems with more than 3GB. This is usually needed for USB,
762 sound, many IDE/SATA chipsets and some other devices.
763 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
764 based hardware IOMMU and a software bounce buffer based IOMMU used
765 on Intel systems and as fallback.
766 The code is only active when needed (enough memory and limited
767 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
771 bool "IBM Calgary IOMMU support"
773 depends on X86_64 && PCI
775 Support for hardware IOMMUs in IBM's xSeries x366 and x460
776 systems. Needed to run systems with more than 3GB of memory
777 properly with 32-bit PCI devices that do not support DAC
778 (Double Address Cycle). Calgary also supports bus level
779 isolation, where all DMAs pass through the IOMMU. This
780 prevents them from going anywhere except their intended
781 destination. This catches hard-to-find kernel bugs and
782 mis-behaving drivers and devices that do not use the DMA-API
783 properly to set up their DMA buffers. The IOMMU can be
784 turned off at boot time with the iommu=off parameter.
785 Normally the kernel will make the right choice by itself.
788 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
790 prompt "Should Calgary be enabled by default?"
791 depends on CALGARY_IOMMU
793 Should Calgary be enabled by default? if you choose 'y', Calgary
794 will be used (if it exists). If you choose 'n', Calgary will not be
795 used even if it exists. If you choose 'n' and would like to use
796 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
799 # need this always selected by IOMMU for the VIA workaround
803 Support for software bounce buffers used on x86-64 systems
804 which don't have a hardware IOMMU. Using this PCI devices
805 which can only access 32-bits of memory can be used on systems
806 with more than 3 GB of memory.
811 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
814 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
815 depends on X86_64 && SMP && DEBUG_KERNEL
816 select CPUMASK_OFFSTACK
818 Enable maximum number of CPUS and NUMA Nodes for this architecture.
822 int "Maximum number of CPUs" if SMP && !MAXSMP
823 range 2 8 if SMP && X86_32 && !X86_BIGSMP
824 range 2 512 if SMP && !MAXSMP
826 default "4096" if MAXSMP
827 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
830 This allows you to specify the maximum number of CPUs which this
831 kernel will support. The maximum supported value is 512 and the
832 minimum value which makes sense is 2.
834 This is purely to save memory - each supported CPU adds
835 approximately eight kilobytes to the kernel image.
838 bool "SMT (Hyperthreading) scheduler support"
841 SMT scheduler support improves the CPU scheduler's decision making
842 when dealing with Intel Pentium 4 chips with HyperThreading at a
843 cost of slightly increased overhead in some places. If unsure say
848 prompt "Multi-core scheduler support"
851 Multi-core scheduler support improves the CPU scheduler's decision
852 making when dealing with multi-core CPU chips at a cost of slightly
853 increased overhead in some places. If unsure say N here.
855 source "kernel/Kconfig.preempt"
858 bool "Local APIC support on uniprocessors"
859 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
861 A local APIC (Advanced Programmable Interrupt Controller) is an
862 integrated interrupt controller in the CPU. If you have a single-CPU
863 system which has a processor with a local APIC, you can say Y here to
864 enable and use it. If you say Y here even though your machine doesn't
865 have a local APIC, then the kernel will still run with no slowdown at
866 all. The local APIC supports CPU-generated self-interrupts (timer,
867 performance counters), and the NMI watchdog which detects hard
871 bool "IO-APIC support on uniprocessors"
872 depends on X86_UP_APIC
874 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
875 SMP-capable replacement for PC-style interrupt controllers. Most
876 SMP systems and many recent uniprocessor systems have one.
878 If you have a single-CPU system with an IO-APIC, you can say Y here
879 to use it. If you say Y here even though your machine doesn't have
880 an IO-APIC, then the kernel will still run with no slowdown at all.
882 config X86_LOCAL_APIC
884 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
888 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
890 config X86_VISWS_APIC
892 depends on X86_32 && X86_VISWS
894 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
895 bool "Reroute for broken boot IRQs"
896 depends on X86_IO_APIC
898 This option enables a workaround that fixes a source of
899 spurious interrupts. This is recommended when threaded
900 interrupt handling is used on systems where the generation of
901 superfluous "boot interrupts" cannot be disabled.
903 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
904 entry in the chipset's IO-APIC is masked (as, e.g. the RT
905 kernel does during interrupt handling). On chipsets where this
906 boot IRQ generation cannot be disabled, this workaround keeps
907 the original IRQ line masked so that only the equivalent "boot
908 IRQ" is delivered to the CPUs. The workaround also tells the
909 kernel to set up the IRQ handler on the boot IRQ line. In this
910 way only one interrupt is delivered to the kernel. Otherwise
911 the spurious second interrupt may cause the kernel to bring
912 down (vital) interrupt lines.
914 Only affects "broken" chipsets. Interrupt sharing may be
915 increased on these systems.
918 bool "Machine Check / overheating reporting"
921 Machine Check support allows the processor to notify the
922 kernel if it detects a problem (e.g. overheating, data corruption).
923 The action the kernel takes depends on the severity of the problem,
924 ranging from warning messages to halting the machine.
928 prompt "Intel MCE features"
929 depends on X86_MCE && X86_LOCAL_APIC
931 Additional support for intel specific MCE features such as
936 prompt "AMD MCE features"
937 depends on X86_MCE && X86_LOCAL_APIC
939 Additional support for AMD specific MCE features such as
940 the DRAM Error Threshold.
942 config X86_ANCIENT_MCE
943 bool "Support for old Pentium 5 / WinChip machine checks"
944 depends on X86_32 && X86_MCE
946 Include support for machine check handling on old Pentium 5 or WinChip
947 systems. These typically need to be enabled explicitely on the command
950 config X86_MCE_THRESHOLD
951 depends on X86_MCE_AMD || X86_MCE_INTEL
954 config X86_MCE_INJECT
956 tristate "Machine check injector support"
958 Provide support for injecting machine checks for testing purposes.
959 If you don't know what a machine check is and you don't do kernel
960 QA it is safe to say n.
962 config X86_THERMAL_VECTOR
964 depends on X86_MCE_INTEL
967 bool "Enable VM86 support" if EXPERT
971 This option is required by programs like DOSEMU to run 16-bit legacy
972 code on X86 processors. It also may be needed by software like
973 XFree86 to initialize some video cards via BIOS. Disabling this
974 option saves about 6k.
977 tristate "Toshiba Laptop support"
980 This adds a driver to safely access the System Management Mode of
981 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
982 not work on models with a Phoenix BIOS. The System Management Mode
983 is used to set the BIOS and power saving options on Toshiba portables.
985 For information on utilities to make use of this driver see the
986 Toshiba Linux utilities web site at:
987 <http://www.buzzard.org.uk/toshiba/>.
989 Say Y if you intend to run this kernel on a Toshiba portable.
993 tristate "Dell laptop support"
996 This adds a driver to safely access the System Management Mode
997 of the CPU on the Dell Inspiron 8000. The System Management Mode
998 is used to read cpu temperature and cooling fan status and to
999 control the fans on the I8K portables.
1001 This driver has been tested only on the Inspiron 8000 but it may
1002 also work with other Dell laptops. You can force loading on other
1003 models by passing the parameter `force=1' to the module. Use at
1006 For information on utilities to make use of this driver see the
1007 I8K Linux utilities web site at:
1008 <http://people.debian.org/~dz/i8k/>
1010 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1013 config X86_REBOOTFIXUPS
1014 bool "Enable X86 board specific fixups for reboot"
1017 This enables chipset and/or board specific fixups to be done
1018 in order to get reboot to work correctly. This is only needed on
1019 some combinations of hardware and BIOS. The symptom, for which
1020 this config is intended, is when reboot ends with a stalled/hung
1023 Currently, the only fixup is for the Geode machines using
1024 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1026 Say Y if you want to enable the fixup. Currently, it's safe to
1027 enable this option even if you don't need it.
1031 tristate "CPU microcode loading support"
1035 If you say Y here, you will be able to update the microcode on
1036 certain Intel and AMD processors. The Intel support is for the
1037 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1038 Xeon etc. The AMD support is for families 0x10 and later. You will
1039 obviously need the actual microcode binary data itself which is not
1040 shipped with the Linux kernel.
1042 This option selects the general module only, you need to select
1043 at least one vendor specific module as well.
1045 To compile this driver as a module, choose M here: the module
1046 will be called microcode.
1048 config MICROCODE_INTEL
1049 bool "Intel microcode loading support"
1050 depends on MICROCODE
1054 This options enables microcode patch loading support for Intel
1057 For latest news and information on obtaining all the required
1058 Intel ingredients for this driver, check:
1059 <http://www.urbanmyth.org/microcode/>.
1061 config MICROCODE_AMD
1062 bool "AMD microcode loading support"
1063 depends on MICROCODE
1066 If you select this option, microcode patch loading support for AMD
1067 processors will be enabled.
1069 config MICROCODE_OLD_INTERFACE
1071 depends on MICROCODE
1073 config MICROCODE_INTEL_LIB
1075 depends on MICROCODE_INTEL
1077 config MICROCODE_INTEL_EARLY
1080 config MICROCODE_AMD_EARLY
1083 config MICROCODE_EARLY
1084 bool "Early load microcode"
1085 depends on MICROCODE=y && BLK_DEV_INITRD
1086 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1087 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1090 This option provides functionality to read additional microcode data
1091 at the beginning of initrd image. The data tells kernel to load
1092 microcode to CPU's as early as possible. No functional change if no
1093 microcode data is glued to the initrd, therefore it's safe to say Y.
1096 tristate "/dev/cpu/*/msr - Model-specific register support"
1098 This device gives privileged processes access to the x86
1099 Model-Specific Registers (MSRs). It is a character device with
1100 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1101 MSR accesses are directed to a specific CPU on multi-processor
1105 tristate "/dev/cpu/*/cpuid - CPU information support"
1107 This device gives processes access to the x86 CPUID instruction to
1108 be executed on a specific processor. It is a character device
1109 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1113 prompt "High Memory Support"
1114 default HIGHMEM64G if X86_NUMAQ
1120 depends on !X86_NUMAQ
1122 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1123 However, the address space of 32-bit x86 processors is only 4
1124 Gigabytes large. That means that, if you have a large amount of
1125 physical memory, not all of it can be "permanently mapped" by the
1126 kernel. The physical memory that's not permanently mapped is called
1129 If you are compiling a kernel which will never run on a machine with
1130 more than 1 Gigabyte total physical RAM, answer "off" here (default
1131 choice and suitable for most users). This will result in a "3GB/1GB"
1132 split: 3GB are mapped so that each process sees a 3GB virtual memory
1133 space and the remaining part of the 4GB virtual memory space is used
1134 by the kernel to permanently map as much physical memory as
1137 If the machine has between 1 and 4 Gigabytes physical RAM, then
1140 If more than 4 Gigabytes is used then answer "64GB" here. This
1141 selection turns Intel PAE (Physical Address Extension) mode on.
1142 PAE implements 3-level paging on IA32 processors. PAE is fully
1143 supported by Linux, PAE mode is implemented on all recent Intel
1144 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1145 then the kernel will not boot on CPUs that don't support PAE!
1147 The actual amount of total physical memory will either be
1148 auto detected or can be forced by using a kernel command line option
1149 such as "mem=256M". (Try "man bootparam" or see the documentation of
1150 your boot loader (lilo or loadlin) about how to pass options to the
1151 kernel at boot time.)
1153 If unsure, say "off".
1157 depends on !X86_NUMAQ
1159 Select this if you have a 32-bit processor and between 1 and 4
1160 gigabytes of physical RAM.
1167 Select this if you have a 32-bit processor and more than 4
1168 gigabytes of physical RAM.
1173 prompt "Memory split" if EXPERT
1177 Select the desired split between kernel and user memory.
1179 If the address range available to the kernel is less than the
1180 physical memory installed, the remaining memory will be available
1181 as "high memory". Accessing high memory is a little more costly
1182 than low memory, as it needs to be mapped into the kernel first.
1183 Note that increasing the kernel address space limits the range
1184 available to user programs, making the address space there
1185 tighter. Selecting anything other than the default 3G/1G split
1186 will also likely make your kernel incompatible with binary-only
1189 If you are not absolutely sure what you are doing, leave this
1193 bool "3G/1G user/kernel split"
1194 config VMSPLIT_3G_OPT
1196 bool "3G/1G user/kernel split (for full 1G low memory)"
1198 bool "2G/2G user/kernel split"
1199 config VMSPLIT_2G_OPT
1201 bool "2G/2G user/kernel split (for full 2G low memory)"
1203 bool "1G/3G user/kernel split"
1208 default 0xB0000000 if VMSPLIT_3G_OPT
1209 default 0x80000000 if VMSPLIT_2G
1210 default 0x78000000 if VMSPLIT_2G_OPT
1211 default 0x40000000 if VMSPLIT_1G
1217 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1220 bool "PAE (Physical Address Extension) Support"
1221 depends on X86_32 && !HIGHMEM4G
1223 PAE is required for NX support, and furthermore enables
1224 larger swapspace support for non-overcommit purposes. It
1225 has the cost of more pagetable lookup overhead, and also
1226 consumes more pagetable space per process.
1228 config ARCH_PHYS_ADDR_T_64BIT
1230 depends on X86_64 || X86_PAE
1232 config ARCH_DMA_ADDR_T_64BIT
1234 depends on X86_64 || HIGHMEM64G
1236 config DIRECT_GBPAGES
1237 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1241 Allow the kernel linear mapping to use 1GB pages on CPUs that
1242 support it. This can improve the kernel's performance a tiny bit by
1243 reducing TLB pressure. If in doubt, say "Y".
1245 # Common NUMA Features
1247 bool "Numa Memory Allocation and Scheduler Support"
1249 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1250 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1252 Enable NUMA (Non Uniform Memory Access) support.
1254 The kernel will try to allocate memory used by a CPU on the
1255 local memory controller of the CPU and add some more
1256 NUMA awareness to the kernel.
1258 For 64-bit this is recommended if the system is Intel Core i7
1259 (or later), AMD Opteron, or EM64T NUMA.
1261 For 32-bit this is only needed on (rare) 32-bit-only platforms
1262 that support NUMA topologies, such as NUMAQ / Summit, or if you
1263 boot a 32-bit kernel on a 64-bit NUMA platform.
1265 Otherwise, you should say N.
1267 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1268 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1272 prompt "Old style AMD Opteron NUMA detection"
1273 depends on X86_64 && NUMA && PCI
1275 Enable AMD NUMA node topology detection. You should say Y here if
1276 you have a multi processor AMD system. This uses an old method to
1277 read the NUMA configuration directly from the builtin Northbridge
1278 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1279 which also takes priority if both are compiled in.
1281 config X86_64_ACPI_NUMA
1283 prompt "ACPI NUMA detection"
1284 depends on X86_64 && NUMA && ACPI && PCI
1287 Enable ACPI SRAT based node topology detection.
1289 # Some NUMA nodes have memory ranges that span
1290 # other nodes. Even though a pfn is valid and
1291 # between a node's start and end pfns, it may not
1292 # reside on that node. See memmap_init_zone()
1294 config NODES_SPAN_OTHER_NODES
1296 depends on X86_64_ACPI_NUMA
1299 bool "NUMA emulation"
1302 Enable NUMA emulation. A flat machine will be split
1303 into virtual nodes when booted with "numa=fake=N", where N is the
1304 number of nodes. This is only useful for debugging.
1307 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1309 default "10" if MAXSMP
1310 default "6" if X86_64
1311 default "4" if X86_NUMAQ
1313 depends on NEED_MULTIPLE_NODES
1315 Specify the maximum number of NUMA Nodes available on the target
1316 system. Increases memory reserved to accommodate various tables.
1318 config ARCH_HAVE_MEMORY_PRESENT
1320 depends on X86_32 && DISCONTIGMEM
1322 config NEED_NODE_MEMMAP_SIZE
1324 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1326 config ARCH_FLATMEM_ENABLE
1328 depends on X86_32 && !NUMA
1330 config ARCH_DISCONTIGMEM_ENABLE
1332 depends on NUMA && X86_32
1334 config ARCH_DISCONTIGMEM_DEFAULT
1336 depends on NUMA && X86_32
1338 config ARCH_SPARSEMEM_ENABLE
1340 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1341 select SPARSEMEM_STATIC if X86_32
1342 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1344 config ARCH_SPARSEMEM_DEFAULT
1348 config ARCH_SELECT_MEMORY_MODEL
1350 depends on ARCH_SPARSEMEM_ENABLE
1352 config ARCH_MEMORY_PROBE
1353 bool "Enable sysfs memory/probe interface"
1354 depends on X86_64 && MEMORY_HOTPLUG
1356 This option enables a sysfs memory/probe interface for testing.
1357 See Documentation/memory-hotplug.txt for more information.
1358 If you are unsure how to answer this question, answer N.
1360 config ARCH_PROC_KCORE_TEXT
1362 depends on X86_64 && PROC_KCORE
1364 config ILLEGAL_POINTER_VALUE
1367 default 0xdead000000000000 if X86_64
1372 bool "Allocate 3rd-level pagetables from highmem"
1375 The VM uses one page table entry for each page of physical memory.
1376 For systems with a lot of RAM, this can be wasteful of precious
1377 low memory. Setting this option will put user-space page table
1378 entries in high memory.
1380 config X86_CHECK_BIOS_CORRUPTION
1381 bool "Check for low memory corruption"
1383 Periodically check for memory corruption in low memory, which
1384 is suspected to be caused by BIOS. Even when enabled in the
1385 configuration, it is disabled at runtime. Enable it by
1386 setting "memory_corruption_check=1" on the kernel command
1387 line. By default it scans the low 64k of memory every 60
1388 seconds; see the memory_corruption_check_size and
1389 memory_corruption_check_period parameters in
1390 Documentation/kernel-parameters.txt to adjust this.
1392 When enabled with the default parameters, this option has
1393 almost no overhead, as it reserves a relatively small amount
1394 of memory and scans it infrequently. It both detects corruption
1395 and prevents it from affecting the running system.
1397 It is, however, intended as a diagnostic tool; if repeatable
1398 BIOS-originated corruption always affects the same memory,
1399 you can use memmap= to prevent the kernel from using that
1402 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1403 bool "Set the default setting of memory_corruption_check"
1404 depends on X86_CHECK_BIOS_CORRUPTION
1407 Set whether the default state of memory_corruption_check is
1410 config X86_RESERVE_LOW
1411 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1415 Specify the amount of low memory to reserve for the BIOS.
1417 The first page contains BIOS data structures that the kernel
1418 must not use, so that page must always be reserved.
1420 By default we reserve the first 64K of physical RAM, as a
1421 number of BIOSes are known to corrupt that memory range
1422 during events such as suspend/resume or monitor cable
1423 insertion, so it must not be used by the kernel.
1425 You can set this to 4 if you are absolutely sure that you
1426 trust the BIOS to get all its memory reservations and usages
1427 right. If you know your BIOS have problems beyond the
1428 default 64K area, you can set this to 640 to avoid using the
1429 entire low memory range.
1431 If you have doubts about the BIOS (e.g. suspend/resume does
1432 not work or there's kernel crashes after certain hardware
1433 hotplug events) then you might want to enable
1434 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1435 typical corruption patterns.
1437 Leave this to the default value of 64 if you are unsure.
1439 config MATH_EMULATION
1441 prompt "Math emulation" if X86_32
1443 Linux can emulate a math coprocessor (used for floating point
1444 operations) if you don't have one. 486DX and Pentium processors have
1445 a math coprocessor built in, 486SX and 386 do not, unless you added
1446 a 487DX or 387, respectively. (The messages during boot time can
1447 give you some hints here ["man dmesg"].) Everyone needs either a
1448 coprocessor or this emulation.
1450 If you don't have a math coprocessor, you need to say Y here; if you
1451 say Y here even though you have a coprocessor, the coprocessor will
1452 be used nevertheless. (This behavior can be changed with the kernel
1453 command line option "no387", which comes handy if your coprocessor
1454 is broken. Try "man bootparam" or see the documentation of your boot
1455 loader (lilo or loadlin) about how to pass options to the kernel at
1456 boot time.) This means that it is a good idea to say Y here if you
1457 intend to use this kernel on different machines.
1459 More information about the internals of the Linux math coprocessor
1460 emulation can be found in <file:arch/x86/math-emu/README>.
1462 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1463 kernel, it won't hurt.
1467 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1469 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1470 the Memory Type Range Registers (MTRRs) may be used to control
1471 processor access to memory ranges. This is most useful if you have
1472 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1473 allows bus write transfers to be combined into a larger transfer
1474 before bursting over the PCI/AGP bus. This can increase performance
1475 of image write operations 2.5 times or more. Saying Y here creates a
1476 /proc/mtrr file which may be used to manipulate your processor's
1477 MTRRs. Typically the X server should use this.
1479 This code has a reasonably generic interface so that similar
1480 control registers on other processors can be easily supported
1483 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1484 Registers (ARRs) which provide a similar functionality to MTRRs. For
1485 these, the ARRs are used to emulate the MTRRs.
1486 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1487 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1488 write-combining. All of these processors are supported by this code
1489 and it makes sense to say Y here if you have one of them.
1491 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1492 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1493 can lead to all sorts of problems, so it's good to say Y here.
1495 You can safely say Y even if your machine doesn't have MTRRs, you'll
1496 just add about 9 KB to your kernel.
1498 See <file:Documentation/x86/mtrr.txt> for more information.
1500 config MTRR_SANITIZER
1502 prompt "MTRR cleanup support"
1505 Convert MTRR layout from continuous to discrete, so X drivers can
1506 add writeback entries.
1508 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1509 The largest mtrr entry size for a continuous block can be set with
1514 config MTRR_SANITIZER_ENABLE_DEFAULT
1515 int "MTRR cleanup enable value (0-1)"
1518 depends on MTRR_SANITIZER
1520 Enable mtrr cleanup default value
1522 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1523 int "MTRR cleanup spare reg num (0-7)"
1526 depends on MTRR_SANITIZER
1528 mtrr cleanup spare entries default, it can be changed via
1529 mtrr_spare_reg_nr=N on the kernel command line.
1533 prompt "x86 PAT support" if EXPERT
1536 Use PAT attributes to setup page level cache control.
1538 PATs are the modern equivalents of MTRRs and are much more
1539 flexible than MTRRs.
1541 Say N here if you see bootup problems (boot crash, boot hang,
1542 spontaneous reboots) or a non-working video driver.
1546 config ARCH_USES_PG_UNCACHED
1552 prompt "x86 architectural random number generator" if EXPERT
1554 Enable the x86 architectural RDRAND instruction
1555 (Intel Bull Mountain technology) to generate random numbers.
1556 If supported, this is a high bandwidth, cryptographically
1557 secure hardware random number generator.
1561 prompt "Supervisor Mode Access Prevention" if EXPERT
1563 Supervisor Mode Access Prevention (SMAP) is a security
1564 feature in newer Intel processors. There is a small
1565 performance cost if this enabled and turned on; there is
1566 also a small increase in the kernel size if this is enabled.
1571 bool "EFI runtime service support"
1575 This enables the kernel to use EFI runtime services that are
1576 available (such as the EFI variable services).
1578 This option is only useful on systems that have EFI firmware.
1579 In addition, you should use the latest ELILO loader available
1580 at <http://elilo.sourceforge.net> in order to take advantage
1581 of EFI runtime services. However, even with this option, the
1582 resultant kernel should continue to boot on existing non-EFI
1586 bool "EFI stub support"
1589 This kernel feature allows a bzImage to be loaded directly
1590 by EFI firmware without the use of a bootloader.
1592 See Documentation/x86/efi-stub.txt for more information.
1596 prompt "Enable seccomp to safely compute untrusted bytecode"
1598 This kernel feature is useful for number crunching applications
1599 that may need to compute untrusted bytecode during their
1600 execution. By using pipes or other transports made available to
1601 the process as file descriptors supporting the read/write
1602 syscalls, it's possible to isolate those applications in
1603 their own address space using seccomp. Once seccomp is
1604 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1605 and the task is only allowed to execute a few safe syscalls
1606 defined by each seccomp mode.
1608 If unsure, say Y. Only embedded should say N here.
1610 config CC_STACKPROTECTOR
1611 bool "Enable -fstack-protector buffer overflow detection"
1613 This option turns on the -fstack-protector GCC feature. This
1614 feature puts, at the beginning of functions, a canary value on
1615 the stack just before the return address, and validates
1616 the value just before actually returning. Stack based buffer
1617 overflows (that need to overwrite this return address) now also
1618 overwrite the canary, which gets detected and the attack is then
1619 neutralized via a kernel panic.
1621 This feature requires gcc version 4.2 or above, or a distribution
1622 gcc with the feature backported. Older versions are automatically
1623 detected and for those versions, this configuration option is
1624 ignored. (and a warning is printed during bootup)
1626 source kernel/Kconfig.hz
1629 bool "kexec system call"
1631 kexec is a system call that implements the ability to shutdown your
1632 current kernel, and to start another kernel. It is like a reboot
1633 but it is independent of the system firmware. And like a reboot
1634 you can start any kernel with it, not just Linux.
1636 The name comes from the similarity to the exec system call.
1638 It is an ongoing process to be certain the hardware in a machine
1639 is properly shutdown, so do not be surprised if this code does not
1640 initially work for you. As of this writing the exact hardware
1641 interface is strongly in flux, so no good recommendation can be
1645 bool "kernel crash dumps"
1646 depends on X86_64 || (X86_32 && HIGHMEM)
1648 Generate crash dump after being started by kexec.
1649 This should be normally only set in special crash dump kernels
1650 which are loaded in the main kernel with kexec-tools into
1651 a specially reserved region and then later executed after
1652 a crash by kdump/kexec. The crash dump kernel must be compiled
1653 to a memory address not used by the main kernel or BIOS using
1654 PHYSICAL_START, or it must be built as a relocatable image
1655 (CONFIG_RELOCATABLE=y).
1656 For more details see Documentation/kdump/kdump.txt
1660 depends on KEXEC && HIBERNATION
1662 Jump between original kernel and kexeced kernel and invoke
1663 code in physical address mode via KEXEC
1665 config PHYSICAL_START
1666 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1669 This gives the physical address where the kernel is loaded.
1671 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1672 bzImage will decompress itself to above physical address and
1673 run from there. Otherwise, bzImage will run from the address where
1674 it has been loaded by the boot loader and will ignore above physical
1677 In normal kdump cases one does not have to set/change this option
1678 as now bzImage can be compiled as a completely relocatable image
1679 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1680 address. This option is mainly useful for the folks who don't want
1681 to use a bzImage for capturing the crash dump and want to use a
1682 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1683 to be specifically compiled to run from a specific memory area
1684 (normally a reserved region) and this option comes handy.
1686 So if you are using bzImage for capturing the crash dump,
1687 leave the value here unchanged to 0x1000000 and set
1688 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1689 for capturing the crash dump change this value to start of
1690 the reserved region. In other words, it can be set based on
1691 the "X" value as specified in the "crashkernel=YM@XM"
1692 command line boot parameter passed to the panic-ed
1693 kernel. Please take a look at Documentation/kdump/kdump.txt
1694 for more details about crash dumps.
1696 Usage of bzImage for capturing the crash dump is recommended as
1697 one does not have to build two kernels. Same kernel can be used
1698 as production kernel and capture kernel. Above option should have
1699 gone away after relocatable bzImage support is introduced. But it
1700 is present because there are users out there who continue to use
1701 vmlinux for dump capture. This option should go away down the
1704 Don't change this unless you know what you are doing.
1707 bool "Build a relocatable kernel"
1710 This builds a kernel image that retains relocation information
1711 so it can be loaded someplace besides the default 1MB.
1712 The relocations tend to make the kernel binary about 10% larger,
1713 but are discarded at runtime.
1715 One use is for the kexec on panic case where the recovery kernel
1716 must live at a different physical address than the primary
1719 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1720 it has been loaded at and the compile time physical address
1721 (CONFIG_PHYSICAL_START) is ignored.
1723 # Relocation on x86-32 needs some additional build support
1724 config X86_NEED_RELOCS
1726 depends on X86_32 && RELOCATABLE
1728 config PHYSICAL_ALIGN
1729 hex "Alignment value to which kernel should be aligned"
1731 range 0x2000 0x1000000 if X86_32
1732 range 0x200000 0x1000000 if X86_64
1734 This value puts the alignment restrictions on physical address
1735 where kernel is loaded and run from. Kernel is compiled for an
1736 address which meets above alignment restriction.
1738 If bootloader loads the kernel at a non-aligned address and
1739 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1740 address aligned to above value and run from there.
1742 If bootloader loads the kernel at a non-aligned address and
1743 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1744 load address and decompress itself to the address it has been
1745 compiled for and run from there. The address for which kernel is
1746 compiled already meets above alignment restrictions. Hence the
1747 end result is that kernel runs from a physical address meeting
1748 above alignment restrictions.
1750 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1751 this value must be a multiple of 0x200000.
1753 Don't change this unless you know what you are doing.
1756 bool "Support for hot-pluggable CPUs"
1759 Say Y here to allow turning CPUs off and on. CPUs can be
1760 controlled through /sys/devices/system/cpu.
1761 ( Note: power management support will enable this option
1762 automatically on SMP systems. )
1763 Say N if you want to disable CPU hotplug.
1765 config BOOTPARAM_HOTPLUG_CPU0
1766 bool "Set default setting of cpu0_hotpluggable"
1768 depends on HOTPLUG_CPU
1770 Set whether default state of cpu0_hotpluggable is on or off.
1772 Say Y here to enable CPU0 hotplug by default. If this switch
1773 is turned on, there is no need to give cpu0_hotplug kernel
1774 parameter and the CPU0 hotplug feature is enabled by default.
1776 Please note: there are two known CPU0 dependencies if you want
1777 to enable the CPU0 hotplug feature either by this switch or by
1778 cpu0_hotplug kernel parameter.
1780 First, resume from hibernate or suspend always starts from CPU0.
1781 So hibernate and suspend are prevented if CPU0 is offline.
1783 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1784 offline if any interrupt can not migrate out of CPU0. There may
1785 be other CPU0 dependencies.
1787 Please make sure the dependencies are under your control before
1788 you enable this feature.
1790 Say N if you don't want to enable CPU0 hotplug feature by default.
1791 You still can enable the CPU0 hotplug feature at boot by kernel
1792 parameter cpu0_hotplug.
1794 config DEBUG_HOTPLUG_CPU0
1796 prompt "Debug CPU0 hotplug"
1797 depends on HOTPLUG_CPU
1799 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1800 soon as possible and boots up userspace with CPU0 offlined. User
1801 can online CPU0 back after boot time.
1803 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1804 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1805 compilation or giving cpu0_hotplug kernel parameter at boot.
1811 prompt "Compat VDSO support"
1812 depends on X86_32 || IA32_EMULATION
1814 Map the 32-bit VDSO to the predictable old-style address too.
1816 Say N here if you are running a sufficiently recent glibc
1817 version (2.3.3 or later), to remove the high-mapped
1818 VDSO mapping and to exclusively use the randomized VDSO.
1823 bool "Built-in kernel command line"
1825 Allow for specifying boot arguments to the kernel at
1826 build time. On some systems (e.g. embedded ones), it is
1827 necessary or convenient to provide some or all of the
1828 kernel boot arguments with the kernel itself (that is,
1829 to not rely on the boot loader to provide them.)
1831 To compile command line arguments into the kernel,
1832 set this option to 'Y', then fill in the
1833 the boot arguments in CONFIG_CMDLINE.
1835 Systems with fully functional boot loaders (i.e. non-embedded)
1836 should leave this option set to 'N'.
1839 string "Built-in kernel command string"
1840 depends on CMDLINE_BOOL
1843 Enter arguments here that should be compiled into the kernel
1844 image and used at boot time. If the boot loader provides a
1845 command line at boot time, it is appended to this string to
1846 form the full kernel command line, when the system boots.
1848 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1849 change this behavior.
1851 In most cases, the command line (whether built-in or provided
1852 by the boot loader) should specify the device for the root
1855 config CMDLINE_OVERRIDE
1856 bool "Built-in command line overrides boot loader arguments"
1857 depends on CMDLINE_BOOL
1859 Set this option to 'Y' to have the kernel ignore the boot loader
1860 command line, and use ONLY the built-in command line.
1862 This is used to work around broken boot loaders. This should
1863 be set to 'N' under normal conditions.
1867 config ARCH_ENABLE_MEMORY_HOTPLUG
1869 depends on X86_64 || (X86_32 && HIGHMEM)
1871 config ARCH_ENABLE_MEMORY_HOTREMOVE
1873 depends on MEMORY_HOTPLUG
1875 config USE_PERCPU_NUMA_NODE_ID
1879 menu "Power management and ACPI options"
1881 config ARCH_HIBERNATION_HEADER
1883 depends on X86_64 && HIBERNATION
1885 source "kernel/power/Kconfig"
1887 source "drivers/acpi/Kconfig"
1889 source "drivers/sfi/Kconfig"
1896 tristate "APM (Advanced Power Management) BIOS support"
1897 depends on X86_32 && PM_SLEEP
1899 APM is a BIOS specification for saving power using several different
1900 techniques. This is mostly useful for battery powered laptops with
1901 APM compliant BIOSes. If you say Y here, the system time will be
1902 reset after a RESUME operation, the /proc/apm device will provide
1903 battery status information, and user-space programs will receive
1904 notification of APM "events" (e.g. battery status change).
1906 If you select "Y" here, you can disable actual use of the APM
1907 BIOS by passing the "apm=off" option to the kernel at boot time.
1909 Note that the APM support is almost completely disabled for
1910 machines with more than one CPU.
1912 In order to use APM, you will need supporting software. For location
1913 and more information, read <file:Documentation/power/apm-acpi.txt>
1914 and the Battery Powered Linux mini-HOWTO, available from
1915 <http://www.tldp.org/docs.html#howto>.
1917 This driver does not spin down disk drives (see the hdparm(8)
1918 manpage ("man 8 hdparm") for that), and it doesn't turn off
1919 VESA-compliant "green" monitors.
1921 This driver does not support the TI 4000M TravelMate and the ACER
1922 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1923 desktop machines also don't have compliant BIOSes, and this driver
1924 may cause those machines to panic during the boot phase.
1926 Generally, if you don't have a battery in your machine, there isn't
1927 much point in using this driver and you should say N. If you get
1928 random kernel OOPSes or reboots that don't seem to be related to
1929 anything, try disabling/enabling this option (or disabling/enabling
1932 Some other things you should try when experiencing seemingly random,
1935 1) make sure that you have enough swap space and that it is
1937 2) pass the "no-hlt" option to the kernel
1938 3) switch on floating point emulation in the kernel and pass
1939 the "no387" option to the kernel
1940 4) pass the "floppy=nodma" option to the kernel
1941 5) pass the "mem=4M" option to the kernel (thereby disabling
1942 all but the first 4 MB of RAM)
1943 6) make sure that the CPU is not over clocked.
1944 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1945 8) disable the cache from your BIOS settings
1946 9) install a fan for the video card or exchange video RAM
1947 10) install a better fan for the CPU
1948 11) exchange RAM chips
1949 12) exchange the motherboard.
1951 To compile this driver as a module, choose M here: the
1952 module will be called apm.
1956 config APM_IGNORE_USER_SUSPEND
1957 bool "Ignore USER SUSPEND"
1959 This option will ignore USER SUSPEND requests. On machines with a
1960 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1961 series notebooks, it is necessary to say Y because of a BIOS bug.
1963 config APM_DO_ENABLE
1964 bool "Enable PM at boot time"
1966 Enable APM features at boot time. From page 36 of the APM BIOS
1967 specification: "When disabled, the APM BIOS does not automatically
1968 power manage devices, enter the Standby State, enter the Suspend
1969 State, or take power saving steps in response to CPU Idle calls."
1970 This driver will make CPU Idle calls when Linux is idle (unless this
1971 feature is turned off -- see "Do CPU IDLE calls", below). This
1972 should always save battery power, but more complicated APM features
1973 will be dependent on your BIOS implementation. You may need to turn
1974 this option off if your computer hangs at boot time when using APM
1975 support, or if it beeps continuously instead of suspending. Turn
1976 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1977 T400CDT. This is off by default since most machines do fine without
1982 bool "Make CPU Idle calls when idle"
1984 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1985 On some machines, this can activate improved power savings, such as
1986 a slowed CPU clock rate, when the machine is idle. These idle calls
1987 are made after the idle loop has run for some length of time (e.g.,
1988 333 mS). On some machines, this will cause a hang at boot time or
1989 whenever the CPU becomes idle. (On machines with more than one CPU,
1990 this option does nothing.)
1992 config APM_DISPLAY_BLANK
1993 bool "Enable console blanking using APM"
1995 Enable console blanking using the APM. Some laptops can use this to
1996 turn off the LCD backlight when the screen blanker of the Linux
1997 virtual console blanks the screen. Note that this is only used by
1998 the virtual console screen blanker, and won't turn off the backlight
1999 when using the X Window system. This also doesn't have anything to
2000 do with your VESA-compliant power-saving monitor. Further, this
2001 option doesn't work for all laptops -- it might not turn off your
2002 backlight at all, or it might print a lot of errors to the console,
2003 especially if you are using gpm.
2005 config APM_ALLOW_INTS
2006 bool "Allow interrupts during APM BIOS calls"
2008 Normally we disable external interrupts while we are making calls to
2009 the APM BIOS as a measure to lessen the effects of a badly behaving
2010 BIOS implementation. The BIOS should reenable interrupts if it
2011 needs to. Unfortunately, some BIOSes do not -- especially those in
2012 many of the newer IBM Thinkpads. If you experience hangs when you
2013 suspend, try setting this to Y. Otherwise, say N.
2017 source "drivers/cpufreq/Kconfig"
2019 source "drivers/cpuidle/Kconfig"
2021 source "drivers/idle/Kconfig"
2026 menu "Bus options (PCI etc.)"
2032 Find out whether you have a PCI motherboard. PCI is the name of a
2033 bus system, i.e. the way the CPU talks to the other stuff inside
2034 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2035 VESA. If you have PCI, say Y, otherwise N.
2038 prompt "PCI access mode"
2039 depends on X86_32 && PCI
2042 On PCI systems, the BIOS can be used to detect the PCI devices and
2043 determine their configuration. However, some old PCI motherboards
2044 have BIOS bugs and may crash if this is done. Also, some embedded
2045 PCI-based systems don't have any BIOS at all. Linux can also try to
2046 detect the PCI hardware directly without using the BIOS.
2048 With this option, you can specify how Linux should detect the
2049 PCI devices. If you choose "BIOS", the BIOS will be used,
2050 if you choose "Direct", the BIOS won't be used, and if you
2051 choose "MMConfig", then PCI Express MMCONFIG will be used.
2052 If you choose "Any", the kernel will try MMCONFIG, then the
2053 direct access method and falls back to the BIOS if that doesn't
2054 work. If unsure, go with the default, which is "Any".
2059 config PCI_GOMMCONFIG
2076 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2078 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2081 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2085 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2089 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2093 depends on PCI && XEN
2101 bool "Support mmconfig PCI config space access"
2102 depends on X86_64 && PCI && ACPI
2104 config PCI_CNB20LE_QUIRK
2105 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2108 Read the PCI windows out of the CNB20LE host bridge. This allows
2109 PCI hotplug to work on systems with the CNB20LE chipset which do
2112 There's no public spec for this chipset, and this functionality
2113 is known to be incomplete.
2115 You should say N unless you know you need this.
2117 source "drivers/pci/pcie/Kconfig"
2119 source "drivers/pci/Kconfig"
2121 # x86_64 have no ISA slots, but can have ISA-style DMA.
2123 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2126 Enables ISA-style DMA support for devices requiring such controllers.
2134 Find out whether you have ISA slots on your motherboard. ISA is the
2135 name of a bus system, i.e. the way the CPU talks to the other stuff
2136 inside your box. Other bus systems are PCI, EISA, MicroChannel
2137 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2138 newer boards don't support it. If you have ISA, say Y, otherwise N.
2144 The Extended Industry Standard Architecture (EISA) bus was
2145 developed as an open alternative to the IBM MicroChannel bus.
2147 The EISA bus provided some of the features of the IBM MicroChannel
2148 bus while maintaining backward compatibility with cards made for
2149 the older ISA bus. The EISA bus saw limited use between 1988 and
2150 1995 when it was made obsolete by the PCI bus.
2152 Say Y here if you are building a kernel for an EISA-based machine.
2156 source "drivers/eisa/Kconfig"
2159 tristate "NatSemi SCx200 support"
2161 This provides basic support for National Semiconductor's
2162 (now AMD's) Geode processors. The driver probes for the
2163 PCI-IDs of several on-chip devices, so its a good dependency
2164 for other scx200_* drivers.
2166 If compiled as a module, the driver is named scx200.
2168 config SCx200HR_TIMER
2169 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2173 This driver provides a clocksource built upon the on-chip
2174 27MHz high-resolution timer. Its also a workaround for
2175 NSC Geode SC-1100's buggy TSC, which loses time when the
2176 processor goes idle (as is done by the scheduler). The
2177 other workaround is idle=poll boot option.
2180 bool "One Laptop Per Child support"
2187 Add support for detecting the unique features of the OLPC
2191 bool "OLPC XO-1 Power Management"
2192 depends on OLPC && MFD_CS5535 && PM_SLEEP
2195 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2198 bool "OLPC XO-1 Real Time Clock"
2199 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2201 Add support for the XO-1 real time clock, which can be used as a
2202 programmable wakeup source.
2205 bool "OLPC XO-1 SCI extras"
2206 depends on OLPC && OLPC_XO1_PM
2212 Add support for SCI-based features of the OLPC XO-1 laptop:
2213 - EC-driven system wakeups
2217 - AC adapter status updates
2218 - Battery status updates
2220 config OLPC_XO15_SCI
2221 bool "OLPC XO-1.5 SCI extras"
2222 depends on OLPC && ACPI
2225 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2226 - EC-driven system wakeups
2227 - AC adapter status updates
2228 - Battery status updates
2231 bool "PCEngines ALIX System Support (LED setup)"
2234 This option enables system support for the PCEngines ALIX.
2235 At present this just sets up LEDs for GPIO control on
2236 ALIX2/3/6 boards. However, other system specific setup should
2239 Note: You must still enable the drivers for GPIO and LED support
2240 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2242 Note: You have to set alix.force=1 for boards with Award BIOS.
2245 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2248 This option enables system support for the Soekris Engineering net5501.
2251 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2255 This option enables system support for the Traverse Technologies GEOS.
2258 bool "Technologic Systems TS-5500 platform support"
2260 select CHECK_SIGNATURE
2264 This option enables system support for the Technologic Systems TS-5500.
2270 depends on CPU_SUP_AMD && PCI
2272 source "drivers/pcmcia/Kconfig"
2274 source "drivers/pci/hotplug/Kconfig"
2277 tristate "RapidIO support"
2281 If enabled this option will include drivers and the core
2282 infrastructure code to support RapidIO interconnect devices.
2284 source "drivers/rapidio/Kconfig"
2287 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2289 Firmwares often provide initial graphics framebuffers so the BIOS,
2290 bootloader or kernel can show basic video-output during boot for
2291 user-guidance and debugging. Historically, x86 used the VESA BIOS
2292 Extensions and EFI-framebuffers for this, which are mostly limited
2294 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2295 framebuffers so the new generic system-framebuffer drivers can be
2296 used on x86. If the framebuffer is not compatible with the generic
2297 modes, it is adverticed as fallback platform framebuffer so legacy
2298 drivers like efifb, vesafb and uvesafb can pick it up.
2299 If this option is not selected, all system framebuffers are always
2300 marked as fallback platform framebuffers as usual.
2302 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2303 not be able to pick up generic system framebuffers if this option
2304 is selected. You are highly encouraged to enable simplefb as
2305 replacement if you select this option. simplefb can correctly deal
2306 with generic system framebuffers. But you should still keep vesafb
2307 and others enabled as fallback if a system framebuffer is
2308 incompatible with simplefb.
2315 menu "Executable file formats / Emulations"
2317 source "fs/Kconfig.binfmt"
2319 config IA32_EMULATION
2320 bool "IA32 Emulation"
2323 select COMPAT_BINFMT_ELF
2326 Include code to run legacy 32-bit programs under a
2327 64-bit kernel. You should likely turn this on, unless you're
2328 100% sure that you don't have any 32-bit programs left.
2331 tristate "IA32 a.out support"
2332 depends on IA32_EMULATION
2334 Support old a.out binaries in the 32bit emulation.
2337 bool "x32 ABI for 64-bit mode"
2338 depends on X86_64 && IA32_EMULATION
2340 Include code to run binaries for the x32 native 32-bit ABI
2341 for 64-bit processors. An x32 process gets access to the
2342 full 64-bit register file and wide data path while leaving
2343 pointers at 32 bits for smaller memory footprint.
2345 You will need a recent binutils (2.22 or later) with
2346 elf32_x86_64 support enabled to compile a kernel with this
2351 depends on IA32_EMULATION || X86_X32
2352 select ARCH_WANT_OLD_COMPAT_IPC
2355 config COMPAT_FOR_U64_ALIGNMENT
2358 config SYSVIPC_COMPAT
2370 config HAVE_ATOMIC_IOMAP
2374 config X86_DEV_DMA_OPS
2376 depends on X86_64 || STA2X11
2378 config X86_DMA_REMAP
2382 source "net/Kconfig"
2384 source "drivers/Kconfig"
2386 source "drivers/firmware/Kconfig"
2390 source "arch/x86/Kconfig.debug"
2392 source "security/Kconfig"
2394 source "crypto/Kconfig"
2396 source "arch/x86/kvm/Kconfig"
2398 source "lib/Kconfig"