2 mainmenu "Linux Kernel Configuration for x86"
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
22 config GENERIC_LOCKBREAK
28 config GENERIC_CMOS_UPDATE
31 config CLOCKSOURCE_WATCHDOG
34 config GENERIC_CLOCKEVENTS
37 config GENERIC_CLOCKEVENTS_BROADCAST
39 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
41 config LOCKDEP_SUPPORT
44 config STACKTRACE_SUPPORT
47 config HAVE_LATENCYTOP_SUPPORT
50 config SEMAPHORE_SLEEPERS
65 config GENERIC_ISA_DMA
75 config GENERIC_HWEIGHT
81 config ARCH_MAY_HAVE_PC_FDC
87 config RWSEM_GENERIC_SPINLOCK
90 config RWSEM_XCHGADD_ALGORITHM
93 config ARCH_HAS_ILOG2_U32
96 config ARCH_HAS_ILOG2_U64
99 config GENERIC_CALIBRATE_DELAY
102 config GENERIC_TIME_VSYSCALL
106 config HAVE_SETUP_PER_CPU_AREA
109 config ARCH_SUPPORTS_OPROFILE
115 config ARCH_HIBERNATION_POSSIBLE
117 depends on !SMP || !X86_VOYAGER
119 config ARCH_SUSPEND_POSSIBLE
121 depends on !X86_VOYAGER
127 config ARCH_POPULATES_NODE_MAP
134 # Use the generic interrupt handling code in kernel/irq/:
135 config GENERIC_HARDIRQS
139 config GENERIC_IRQ_PROBE
143 config GENERIC_PENDING_IRQ
145 depends on GENERIC_HARDIRQS && SMP
150 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
155 depends on X86_32 && SMP
159 depends on X86_64 && SMP
164 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8)
167 config X86_BIOS_REBOOT
169 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
172 config X86_TRAMPOLINE
174 depends on X86_SMP || (X86_VOYAGER && SMP)
179 source "init/Kconfig"
181 menu "Processor type and features"
183 source "kernel/time/Kconfig"
186 bool "Symmetric multi-processing support"
188 This enables support for systems with more than one CPU. If you have
189 a system with only one CPU, like most personal computers, say N. If
190 you have a system with more than one CPU, say Y.
192 If you say N here, the kernel will run on single and multiprocessor
193 machines, but will use only one CPU of a multiprocessor machine. If
194 you say Y here, the kernel will run on many, but not all,
195 singleprocessor machines. On a singleprocessor machine, the kernel
196 will run faster if you say N here.
198 Note that if you say Y here and choose architecture "586" or
199 "Pentium" under "Processor family", the kernel will not work on 486
200 architectures. Similarly, multiprocessor kernels for the "PPro"
201 architecture may not work on all Pentium based boards.
203 People using multiprocessor machines who say Y here should also say
204 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
205 Management" code will be disabled if you say Y here.
207 See also <file:Documentation/i386/IO-APIC.txt>,
208 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
209 <http://www.tldp.org/docs.html#howto>.
211 If you don't know what to do here, say N.
214 prompt "Subarchitecture Type"
220 Choose this option if your computer is a standard PC or compatible.
226 Select this for an AMD Elan processor.
228 Do not use this option for K6/Athlon/Opteron processors!
230 If unsure, choose "PC-compatible" instead.
235 select SMP if !BROKEN
237 Voyager is an MCA-based 32-way capable SMP architecture proprietary
238 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
242 If you do not specifically know you have a Voyager based machine,
243 say N here, otherwise the kernel you build will not be bootable.
246 bool "NUMAQ (IBM/Sequent)"
251 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
252 multiquad box. This changes the way that processors are bootstrapped,
253 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
254 You will need a new lynxer.elf file to flash your firmware with - send
255 email to <Martin.Bligh@us.ibm.com>.
258 bool "Summit/EXA (IBM x440)"
259 depends on X86_32 && SMP
261 This option is needed for IBM systems that use the Summit/EXA chipset.
262 In particular, it is needed for the x440.
264 If you don't have one of these computers, you should say N here.
265 If you want to build a NUMA kernel, you must select ACPI.
268 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
269 depends on X86_32 && SMP
271 This option is needed for the systems that have more than 8 CPUs
272 and if the system is not of any sub-arch type above.
274 If you don't have such a system, you should say N here.
277 bool "SGI 320/540 (Visual Workstation)"
280 The SGI Visual Workstation series is an IA32-based workstation
281 based on SGI systems chips with some legacy PC hardware attached.
283 Say Y here to create a kernel to run on the SGI 320 or 540.
285 A kernel compiled for the Visual Workstation will not run on PCs
286 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
288 config X86_GENERICARCH
289 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
292 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
293 It is intended for a generic binary kernel.
294 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
297 bool "Support for Unisys ES7000 IA32 series"
298 depends on X86_32 && SMP
300 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
301 supposed to run on an IA32-based Unisys ES7000 system.
302 Only choose this option if you have such a system, otherwise you
306 bool "RDC R-321x SoC"
309 select X86_REBOOTFIXUPS
313 This option is needed for RDC R-321x system-on-chip, also known
315 If you don't have one of these chips, you should say N here.
318 bool "Support for ScaleMP vSMP"
319 depends on X86_64 && PCI
321 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
322 supposed to run on these EM64T-based machines. Only choose this option
323 if you have one of these machines.
327 config SCHED_NO_NO_OMIT_FRAME_POINTER
329 prompt "Single-depth WCHAN output"
332 Calculate simpler /proc/<PID>/wchan values. If this option
333 is disabled then wchan values will recurse back to the
334 caller function. This provides more accurate wchan values,
335 at the expense of slightly more scheduling overhead.
337 If in doubt, say "Y".
339 menuconfig PARAVIRT_GUEST
340 bool "Paravirtualized guest support"
342 Say Y here to get to see options related to running Linux under
343 various hypervisors. This option alone does not add any kernel code.
345 If you say N, all options in this submenu will be skipped and disabled.
349 source "arch/x86/xen/Kconfig"
352 bool "VMI Guest support"
355 depends on !(X86_VISWS || X86_VOYAGER)
357 VMI provides a paravirtualized interface to the VMware ESX server
358 (it could be used by other hypervisors in theory too, but is not
359 at the moment), by linking the kernel to a GPL-ed ROM module
360 provided by the hypervisor.
362 source "arch/x86/lguest/Kconfig"
365 bool "Enable paravirtualization code"
366 depends on !(X86_VISWS || X86_VOYAGER)
368 This changes the kernel so it can modify itself when it is run
369 under a hypervisor, potentially improving performance significantly
370 over full virtualization. However, when run without a hypervisor
371 the kernel is theoretically slower and slightly larger.
377 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
380 config HAVE_ARCH_PARSE_SRAT
384 config X86_SUMMIT_NUMA
386 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
388 config X86_CYCLONE_TIMER
390 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
392 config ES7000_CLUSTERED_APIC
394 depends on SMP && X86_ES7000 && MPENTIUMIII
396 source "arch/x86/Kconfig.cpu"
400 prompt "HPET Timer Support" if X86_32
402 Use the IA-PC HPET (High Precision Event Timer) to manage
403 time in preference to the PIT and RTC, if a HPET is
405 HPET is the next generation timer replacing legacy 8254s.
406 The HPET provides a stable time base on SMP
407 systems, unlike the TSC, but it is more expensive to access,
408 as it is off-chip. You can find the HPET spec at
409 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
411 You can safely choose Y here. However, HPET will only be
412 activated if the platform and the BIOS support this feature.
413 Otherwise the 8254 will be used for timing services.
415 Choose N to continue using the legacy 8254 timer.
417 config HPET_EMULATE_RTC
419 depends on HPET_TIMER && (RTC=y || RTC=m)
421 # Mark as embedded because too many people got it wrong.
422 # The code disables itself when not needed.
424 bool "GART IOMMU support" if EMBEDDED
428 depends on X86_64 && PCI
430 Support for full DMA access of devices with 32bit memory access only
431 on systems with more than 3GB. This is usually needed for USB,
432 sound, many IDE/SATA chipsets and some other devices.
433 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
434 based hardware IOMMU and a software bounce buffer based IOMMU used
435 on Intel systems and as fallback.
436 The code is only active when needed (enough memory and limited
437 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
441 bool "IBM Calgary IOMMU support"
443 depends on X86_64 && PCI && EXPERIMENTAL
445 Support for hardware IOMMUs in IBM's xSeries x366 and x460
446 systems. Needed to run systems with more than 3GB of memory
447 properly with 32-bit PCI devices that do not support DAC
448 (Double Address Cycle). Calgary also supports bus level
449 isolation, where all DMAs pass through the IOMMU. This
450 prevents them from going anywhere except their intended
451 destination. This catches hard-to-find kernel bugs and
452 mis-behaving drivers and devices that do not use the DMA-API
453 properly to set up their DMA buffers. The IOMMU can be
454 turned off at boot time with the iommu=off parameter.
455 Normally the kernel will make the right choice by itself.
458 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
460 prompt "Should Calgary be enabled by default?"
461 depends on CALGARY_IOMMU
463 Should Calgary be enabled by default? if you choose 'y', Calgary
464 will be used (if it exists). If you choose 'n', Calgary will not be
465 used even if it exists. If you choose 'n' and would like to use
466 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
469 # need this always selected by IOMMU for the VIA workaround
473 Support for software bounce buffers used on x86-64 systems
474 which don't have a hardware IOMMU (e.g. the current generation
475 of Intel's x86-64 CPUs). Using this PCI devices which can only
476 access 32-bits of memory can be used on systems with more than
477 3 GB of memory. If unsure, say Y.
481 int "Maximum number of CPUs (2-255)"
484 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
487 This allows you to specify the maximum number of CPUs which this
488 kernel will support. The maximum supported value is 255 and the
489 minimum value which makes sense is 2.
491 This is purely to save memory - each supported CPU adds
492 approximately eight kilobytes to the kernel image.
495 bool "SMT (Hyperthreading) scheduler support"
496 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
498 SMT scheduler support improves the CPU scheduler's decision making
499 when dealing with Intel Pentium 4 chips with HyperThreading at a
500 cost of slightly increased overhead in some places. If unsure say
505 prompt "Multi-core scheduler support"
506 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
508 Multi-core scheduler support improves the CPU scheduler's decision
509 making when dealing with multi-core CPU chips at a cost of slightly
510 increased overhead in some places. If unsure say N here.
512 source "kernel/Kconfig.preempt"
515 bool "Local APIC support on uniprocessors"
516 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
518 A local APIC (Advanced Programmable Interrupt Controller) is an
519 integrated interrupt controller in the CPU. If you have a single-CPU
520 system which has a processor with a local APIC, you can say Y here to
521 enable and use it. If you say Y here even though your machine doesn't
522 have a local APIC, then the kernel will still run with no slowdown at
523 all. The local APIC supports CPU-generated self-interrupts (timer,
524 performance counters), and the NMI watchdog which detects hard
528 bool "IO-APIC support on uniprocessors"
529 depends on X86_UP_APIC
531 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
532 SMP-capable replacement for PC-style interrupt controllers. Most
533 SMP systems and many recent uniprocessor systems have one.
535 If you have a single-CPU system with an IO-APIC, you can say Y here
536 to use it. If you say Y here even though your machine doesn't have
537 an IO-APIC, then the kernel will still run with no slowdown at all.
539 config X86_LOCAL_APIC
541 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
545 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
547 config X86_VISWS_APIC
549 depends on X86_32 && X86_VISWS
552 bool "Machine Check Exception"
553 depends on !X86_VOYAGER
555 Machine Check Exception support allows the processor to notify the
556 kernel if it detects a problem (e.g. overheating, component failure).
557 The action the kernel takes depends on the severity of the problem,
558 ranging from a warning message on the console, to halting the machine.
559 Your processor must be a Pentium or newer to support this - check the
560 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
561 have a design flaw which leads to false MCE events - hence MCE is
562 disabled on all P5 processors, unless explicitly enabled with "mce"
563 as a boot argument. Similarly, if MCE is built in and creates a
564 problem on some new non-standard machine, you can boot with "nomce"
565 to disable it. MCE support simply ignores non-MCE processors like
566 the 386 and 486, so nearly everyone can say Y here.
570 prompt "Intel MCE features"
571 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
573 Additional support for intel specific MCE features such as
578 prompt "AMD MCE features"
579 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
581 Additional support for AMD specific MCE features such as
582 the DRAM Error Threshold.
584 config X86_MCE_NONFATAL
585 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
586 depends on X86_32 && X86_MCE
588 Enabling this feature starts a timer that triggers every 5 seconds which
589 will look at the machine check registers to see if anything happened.
590 Non-fatal problems automatically get corrected (but still logged).
591 Disable this if you don't want to see these messages.
592 Seeing the messages this option prints out may be indicative of dying
593 or out-of-spec (ie, overclocked) hardware.
594 This option only does something on certain CPUs.
595 (AMD Athlon/Duron and Intel Pentium 4)
597 config X86_MCE_P4THERMAL
598 bool "check for P4 thermal throttling interrupt."
599 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
601 Enabling this feature will cause a message to be printed when the P4
602 enters thermal throttling.
605 bool "Enable VM86 support" if EMBEDDED
609 This option is required by programs like DOSEMU to run 16-bit legacy
610 code on X86 processors. It also may be needed by software like
611 XFree86 to initialize some video cards via BIOS. Disabling this
612 option saves about 6k.
615 tristate "Toshiba Laptop support"
618 This adds a driver to safely access the System Management Mode of
619 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
620 not work on models with a Phoenix BIOS. The System Management Mode
621 is used to set the BIOS and power saving options on Toshiba portables.
623 For information on utilities to make use of this driver see the
624 Toshiba Linux utilities web site at:
625 <http://www.buzzard.org.uk/toshiba/>.
627 Say Y if you intend to run this kernel on a Toshiba portable.
631 tristate "Dell laptop support"
634 This adds a driver to safely access the System Management Mode
635 of the CPU on the Dell Inspiron 8000. The System Management Mode
636 is used to read cpu temperature and cooling fan status and to
637 control the fans on the I8K portables.
639 This driver has been tested only on the Inspiron 8000 but it may
640 also work with other Dell laptops. You can force loading on other
641 models by passing the parameter `force=1' to the module. Use at
644 For information on utilities to make use of this driver see the
645 I8K Linux utilities web site at:
646 <http://people.debian.org/~dz/i8k/>
648 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
651 config X86_REBOOTFIXUPS
653 prompt "Enable X86 board specific fixups for reboot"
654 depends on X86_32 && X86
656 This enables chipset and/or board specific fixups to be done
657 in order to get reboot to work correctly. This is only needed on
658 some combinations of hardware and BIOS. The symptom, for which
659 this config is intended, is when reboot ends with a stalled/hung
662 Currently, the only fixup is for the Geode machines using
663 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
665 Say Y if you want to enable the fixup. Currently, it's safe to
666 enable this option even if you don't need it.
670 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
673 If you say Y here, you will be able to update the microcode on
674 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
675 Pentium III, Pentium 4, Xeon etc. You will obviously need the
676 actual microcode binary data itself which is not shipped with the
679 For latest news and information on obtaining all the required
680 ingredients for this driver, check:
681 <http://www.urbanmyth.org/microcode/>.
683 To compile this driver as a module, choose M here: the
684 module will be called microcode.
686 config MICROCODE_OLD_INTERFACE
691 tristate "/dev/cpu/*/msr - Model-specific register support"
693 This device gives privileged processes access to the x86
694 Model-Specific Registers (MSRs). It is a character device with
695 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
696 MSR accesses are directed to a specific CPU on multi-processor
700 tristate "/dev/cpu/*/cpuid - CPU information support"
702 This device gives processes access to the x86 CPUID instruction to
703 be executed on a specific processor. It is a character device
704 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
708 prompt "High Memory Support"
709 default HIGHMEM4G if !X86_NUMAQ
710 default HIGHMEM64G if X86_NUMAQ
715 depends on !X86_NUMAQ
717 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
718 However, the address space of 32-bit x86 processors is only 4
719 Gigabytes large. That means that, if you have a large amount of
720 physical memory, not all of it can be "permanently mapped" by the
721 kernel. The physical memory that's not permanently mapped is called
724 If you are compiling a kernel which will never run on a machine with
725 more than 1 Gigabyte total physical RAM, answer "off" here (default
726 choice and suitable for most users). This will result in a "3GB/1GB"
727 split: 3GB are mapped so that each process sees a 3GB virtual memory
728 space and the remaining part of the 4GB virtual memory space is used
729 by the kernel to permanently map as much physical memory as
732 If the machine has between 1 and 4 Gigabytes physical RAM, then
735 If more than 4 Gigabytes is used then answer "64GB" here. This
736 selection turns Intel PAE (Physical Address Extension) mode on.
737 PAE implements 3-level paging on IA32 processors. PAE is fully
738 supported by Linux, PAE mode is implemented on all recent Intel
739 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
740 then the kernel will not boot on CPUs that don't support PAE!
742 The actual amount of total physical memory will either be
743 auto detected or can be forced by using a kernel command line option
744 such as "mem=256M". (Try "man bootparam" or see the documentation of
745 your boot loader (lilo or loadlin) about how to pass options to the
746 kernel at boot time.)
748 If unsure, say "off".
752 depends on !X86_NUMAQ
754 Select this if you have a 32-bit processor and between 1 and 4
755 gigabytes of physical RAM.
759 depends on !M386 && !M486
762 Select this if you have a 32-bit processor and more than 4
763 gigabytes of physical RAM.
768 depends on EXPERIMENTAL
769 prompt "Memory split" if EMBEDDED
773 Select the desired split between kernel and user memory.
775 If the address range available to the kernel is less than the
776 physical memory installed, the remaining memory will be available
777 as "high memory". Accessing high memory is a little more costly
778 than low memory, as it needs to be mapped into the kernel first.
779 Note that increasing the kernel address space limits the range
780 available to user programs, making the address space there
781 tighter. Selecting anything other than the default 3G/1G split
782 will also likely make your kernel incompatible with binary-only
785 If you are not absolutely sure what you are doing, leave this
789 bool "3G/1G user/kernel split"
790 config VMSPLIT_3G_OPT
792 bool "3G/1G user/kernel split (for full 1G low memory)"
794 bool "2G/2G user/kernel split"
795 config VMSPLIT_2G_OPT
797 bool "2G/2G user/kernel split (for full 2G low memory)"
799 bool "1G/3G user/kernel split"
804 default 0xB0000000 if VMSPLIT_3G_OPT
805 default 0x80000000 if VMSPLIT_2G
806 default 0x78000000 if VMSPLIT_2G_OPT
807 default 0x40000000 if VMSPLIT_1G
813 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
817 prompt "PAE (Physical Address Extension) Support"
818 depends on X86_32 && !HIGHMEM4G
819 select RESOURCES_64BIT
821 PAE is required for NX support, and furthermore enables
822 larger swapspace support for non-overcommit purposes. It
823 has the cost of more pagetable lookup overhead, and also
824 consumes more pagetable space per process.
826 # Common NUMA Features
828 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
830 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
832 default y if (X86_NUMAQ || X86_SUMMIT)
834 Enable NUMA (Non Uniform Memory Access) support.
835 The kernel will try to allocate memory used by a CPU on the
836 local memory controller of the CPU and add some more
837 NUMA awareness to the kernel.
839 For i386 this is currently highly experimental and should be only
840 used for kernel development. It might also cause boot failures.
841 For x86_64 this is recommended on all multiprocessor Opteron systems.
842 If the system is EM64T, you should say N unless your system is
845 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
846 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
850 prompt "Old style AMD Opteron NUMA detection"
851 depends on X86_64 && NUMA && PCI
853 Enable K8 NUMA node topology detection. You should say Y here if
854 you have a multi processor AMD K8 system. This uses an old
855 method to read the NUMA configuration directly from the builtin
856 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
857 instead, which also takes priority if both are compiled in.
859 config X86_64_ACPI_NUMA
861 prompt "ACPI NUMA detection"
862 depends on X86_64 && NUMA && ACPI && PCI
865 Enable ACPI SRAT based node topology detection.
868 bool "NUMA emulation"
869 depends on X86_64 && NUMA
871 Enable NUMA emulation. A flat machine will be split
872 into virtual nodes when booted with "numa=fake=N", where N is the
873 number of nodes. This is only useful for debugging.
878 default "6" if X86_64
879 default "4" if X86_NUMAQ
881 depends on NEED_MULTIPLE_NODES
883 config HAVE_ARCH_BOOTMEM_NODE
885 depends on X86_32 && NUMA
887 config ARCH_HAVE_MEMORY_PRESENT
889 depends on X86_32 && DISCONTIGMEM
891 config NEED_NODE_MEMMAP_SIZE
893 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
895 config HAVE_ARCH_ALLOC_REMAP
897 depends on X86_32 && NUMA
899 config ARCH_FLATMEM_ENABLE
901 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
903 config ARCH_DISCONTIGMEM_ENABLE
905 depends on NUMA && X86_32
907 config ARCH_DISCONTIGMEM_DEFAULT
909 depends on NUMA && X86_32
911 config ARCH_SPARSEMEM_DEFAULT
915 config ARCH_SPARSEMEM_ENABLE
917 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
918 select SPARSEMEM_STATIC if X86_32
919 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
921 config ARCH_SELECT_MEMORY_MODEL
923 depends on ARCH_SPARSEMEM_ENABLE
925 config ARCH_MEMORY_PROBE
927 depends on MEMORY_HOTPLUG
932 bool "Allocate 3rd-level pagetables from highmem"
933 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
935 The VM uses one page table entry for each page of physical memory.
936 For systems with a lot of RAM, this can be wasteful of precious
937 low memory. Setting this option will put user-space page table
938 entries in high memory.
940 config MATH_EMULATION
942 prompt "Math emulation" if X86_32
944 Linux can emulate a math coprocessor (used for floating point
945 operations) if you don't have one. 486DX and Pentium processors have
946 a math coprocessor built in, 486SX and 386 do not, unless you added
947 a 487DX or 387, respectively. (The messages during boot time can
948 give you some hints here ["man dmesg"].) Everyone needs either a
949 coprocessor or this emulation.
951 If you don't have a math coprocessor, you need to say Y here; if you
952 say Y here even though you have a coprocessor, the coprocessor will
953 be used nevertheless. (This behavior can be changed with the kernel
954 command line option "no387", which comes handy if your coprocessor
955 is broken. Try "man bootparam" or see the documentation of your boot
956 loader (lilo or loadlin) about how to pass options to the kernel at
957 boot time.) This means that it is a good idea to say Y here if you
958 intend to use this kernel on different machines.
960 More information about the internals of the Linux math coprocessor
961 emulation can be found in <file:arch/x86/math-emu/README>.
963 If you are not sure, say Y; apart from resulting in a 66 KB bigger
964 kernel, it won't hurt.
967 bool "MTRR (Memory Type Range Register) support"
969 On Intel P6 family processors (Pentium Pro, Pentium II and later)
970 the Memory Type Range Registers (MTRRs) may be used to control
971 processor access to memory ranges. This is most useful if you have
972 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
973 allows bus write transfers to be combined into a larger transfer
974 before bursting over the PCI/AGP bus. This can increase performance
975 of image write operations 2.5 times or more. Saying Y here creates a
976 /proc/mtrr file which may be used to manipulate your processor's
977 MTRRs. Typically the X server should use this.
979 This code has a reasonably generic interface so that similar
980 control registers on other processors can be easily supported
983 The Cyrix 6x86, 6x86MX and M II processors have Address Range
984 Registers (ARRs) which provide a similar functionality to MTRRs. For
985 these, the ARRs are used to emulate the MTRRs.
986 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
987 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
988 write-combining. All of these processors are supported by this code
989 and it makes sense to say Y here if you have one of them.
991 Saying Y here also fixes a problem with buggy SMP BIOSes which only
992 set the MTRRs for the boot CPU and not for the secondary CPUs. This
993 can lead to all sorts of problems, so it's good to say Y here.
995 You can safely say Y even if your machine doesn't have MTRRs, you'll
996 just add about 9 KB to your kernel.
998 See <file:Documentation/mtrr.txt> for more information.
1002 prompt "EFI runtime service support"
1005 This enables the kernel to use EFI runtime services that are
1006 available (such as the EFI variable services).
1008 This option is only useful on systems that have EFI firmware.
1009 In addition, you should use the latest ELILO loader available
1010 at <http://elilo.sourceforge.net> in order to take advantage
1011 of EFI runtime services. However, even with this option, the
1012 resultant kernel should continue to boot on existing non-EFI
1017 prompt "Enable kernel irq balancing"
1018 depends on X86_32 && SMP && X86_IO_APIC
1020 The default yes will allow the kernel to do irq load balancing.
1021 Saying no will keep the kernel from doing irq load balancing.
1025 prompt "Enable seccomp to safely compute untrusted bytecode"
1028 This kernel feature is useful for number crunching applications
1029 that may need to compute untrusted bytecode during their
1030 execution. By using pipes or other transports made available to
1031 the process as file descriptors supporting the read/write
1032 syscalls, it's possible to isolate those applications in
1033 their own address space using seccomp. Once seccomp is
1034 enabled via /proc/<pid>/seccomp, it cannot be disabled
1035 and the task is only allowed to execute a few safe syscalls
1036 defined by each seccomp mode.
1038 If unsure, say Y. Only embedded should say N here.
1040 config CC_STACKPROTECTOR
1041 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1042 depends on X86_64 && EXPERIMENTAL
1044 This option turns on the -fstack-protector GCC feature. This
1045 feature puts, at the beginning of critical functions, a canary
1046 value on the stack just before the return address, and validates
1047 the value just before actually returning. Stack based buffer
1048 overflows (that need to overwrite this return address) now also
1049 overwrite the canary, which gets detected and the attack is then
1050 neutralized via a kernel panic.
1052 This feature requires gcc version 4.2 or above, or a distribution
1053 gcc with the feature backported. Older versions are automatically
1054 detected and for those versions, this configuration option is ignored.
1056 config CC_STACKPROTECTOR_ALL
1057 bool "Use stack-protector for all functions"
1058 depends on CC_STACKPROTECTOR
1060 Normally, GCC only inserts the canary value protection for
1061 functions that use large-ish on-stack buffers. By enabling
1062 this option, GCC will be asked to do this for ALL functions.
1064 source kernel/Kconfig.hz
1067 bool "kexec system call"
1069 kexec is a system call that implements the ability to shutdown your
1070 current kernel, and to start another kernel. It is like a reboot
1071 but it is independent of the system firmware. And like a reboot
1072 you can start any kernel with it, not just Linux.
1074 The name comes from the similarity to the exec system call.
1076 It is an ongoing process to be certain the hardware in a machine
1077 is properly shutdown, so do not be surprised if this code does not
1078 initially work for you. It may help to enable device hotplugging
1079 support. As of this writing the exact hardware interface is
1080 strongly in flux, so no good recommendation can be made.
1083 bool "kernel crash dumps (EXPERIMENTAL)"
1084 depends on EXPERIMENTAL
1085 depends on X86_64 || (X86_32 && HIGHMEM)
1087 Generate crash dump after being started by kexec.
1088 This should be normally only set in special crash dump kernels
1089 which are loaded in the main kernel with kexec-tools into
1090 a specially reserved region and then later executed after
1091 a crash by kdump/kexec. The crash dump kernel must be compiled
1092 to a memory address not used by the main kernel or BIOS using
1093 PHYSICAL_START, or it must be built as a relocatable image
1094 (CONFIG_RELOCATABLE=y).
1095 For more details see Documentation/kdump/kdump.txt
1097 config PHYSICAL_START
1098 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1099 default "0x1000000" if X86_NUMAQ
1100 default "0x200000" if X86_64
1103 This gives the physical address where the kernel is loaded.
1105 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1106 bzImage will decompress itself to above physical address and
1107 run from there. Otherwise, bzImage will run from the address where
1108 it has been loaded by the boot loader and will ignore above physical
1111 In normal kdump cases one does not have to set/change this option
1112 as now bzImage can be compiled as a completely relocatable image
1113 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1114 address. This option is mainly useful for the folks who don't want
1115 to use a bzImage for capturing the crash dump and want to use a
1116 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1117 to be specifically compiled to run from a specific memory area
1118 (normally a reserved region) and this option comes handy.
1120 So if you are using bzImage for capturing the crash dump, leave
1121 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1122 Otherwise if you plan to use vmlinux for capturing the crash dump
1123 change this value to start of the reserved region (Typically 16MB
1124 0x1000000). In other words, it can be set based on the "X" value as
1125 specified in the "crashkernel=YM@XM" command line boot parameter
1126 passed to the panic-ed kernel. Typically this parameter is set as
1127 crashkernel=64M@16M. Please take a look at
1128 Documentation/kdump/kdump.txt for more details about crash dumps.
1130 Usage of bzImage for capturing the crash dump is recommended as
1131 one does not have to build two kernels. Same kernel can be used
1132 as production kernel and capture kernel. Above option should have
1133 gone away after relocatable bzImage support is introduced. But it
1134 is present because there are users out there who continue to use
1135 vmlinux for dump capture. This option should go away down the
1138 Don't change this unless you know what you are doing.
1141 bool "Build a relocatable kernel (EXPERIMENTAL)"
1142 depends on EXPERIMENTAL
1144 This builds a kernel image that retains relocation information
1145 so it can be loaded someplace besides the default 1MB.
1146 The relocations tend to make the kernel binary about 10% larger,
1147 but are discarded at runtime.
1149 One use is for the kexec on panic case where the recovery kernel
1150 must live at a different physical address than the primary
1153 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1154 it has been loaded at and the compile time physical address
1155 (CONFIG_PHYSICAL_START) is ignored.
1157 config PHYSICAL_ALIGN
1159 prompt "Alignment value to which kernel should be aligned" if X86_32
1160 default "0x100000" if X86_32
1161 default "0x200000" if X86_64
1162 range 0x2000 0x400000
1164 This value puts the alignment restrictions on physical address
1165 where kernel is loaded and run from. Kernel is compiled for an
1166 address which meets above alignment restriction.
1168 If bootloader loads the kernel at a non-aligned address and
1169 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1170 address aligned to above value and run from there.
1172 If bootloader loads the kernel at a non-aligned address and
1173 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1174 load address and decompress itself to the address it has been
1175 compiled for and run from there. The address for which kernel is
1176 compiled already meets above alignment restrictions. Hence the
1177 end result is that kernel runs from a physical address meeting
1178 above alignment restrictions.
1180 Don't change this unless you know what you are doing.
1183 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1184 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1186 Say Y here to experiment with turning CPUs off and on, and to
1187 enable suspend on SMP systems. CPUs can be controlled through
1188 /sys/devices/system/cpu.
1189 Say N if you want to disable CPU hotplug and don't need to
1194 prompt "Compat VDSO support"
1195 depends on X86_32 || IA32_EMULATION
1197 Map the 32-bit VDSO to the predictable old-style address too.
1199 Say N here if you are running a sufficiently recent glibc
1200 version (2.3.3 or later), to remove the high-mapped
1201 VDSO mapping and to exclusively use the randomized VDSO.
1207 config ARCH_ENABLE_MEMORY_HOTPLUG
1209 depends on X86_64 || (X86_32 && HIGHMEM)
1211 config HAVE_ARCH_EARLY_PFN_TO_NID
1215 menu "Power management options"
1216 depends on !X86_VOYAGER
1218 config ARCH_HIBERNATION_HEADER
1220 depends on X86_64 && HIBERNATION
1222 source "kernel/power/Kconfig"
1224 source "drivers/acpi/Kconfig"
1229 depends on APM || APM_MODULE
1232 tristate "APM (Advanced Power Management) BIOS support"
1233 depends on X86_32 && PM_SLEEP && !X86_VISWS
1235 APM is a BIOS specification for saving power using several different
1236 techniques. This is mostly useful for battery powered laptops with
1237 APM compliant BIOSes. If you say Y here, the system time will be
1238 reset after a RESUME operation, the /proc/apm device will provide
1239 battery status information, and user-space programs will receive
1240 notification of APM "events" (e.g. battery status change).
1242 If you select "Y" here, you can disable actual use of the APM
1243 BIOS by passing the "apm=off" option to the kernel at boot time.
1245 Note that the APM support is almost completely disabled for
1246 machines with more than one CPU.
1248 In order to use APM, you will need supporting software. For location
1249 and more information, read <file:Documentation/pm.txt> and the
1250 Battery Powered Linux mini-HOWTO, available from
1251 <http://www.tldp.org/docs.html#howto>.
1253 This driver does not spin down disk drives (see the hdparm(8)
1254 manpage ("man 8 hdparm") for that), and it doesn't turn off
1255 VESA-compliant "green" monitors.
1257 This driver does not support the TI 4000M TravelMate and the ACER
1258 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1259 desktop machines also don't have compliant BIOSes, and this driver
1260 may cause those machines to panic during the boot phase.
1262 Generally, if you don't have a battery in your machine, there isn't
1263 much point in using this driver and you should say N. If you get
1264 random kernel OOPSes or reboots that don't seem to be related to
1265 anything, try disabling/enabling this option (or disabling/enabling
1268 Some other things you should try when experiencing seemingly random,
1271 1) make sure that you have enough swap space and that it is
1273 2) pass the "no-hlt" option to the kernel
1274 3) switch on floating point emulation in the kernel and pass
1275 the "no387" option to the kernel
1276 4) pass the "floppy=nodma" option to the kernel
1277 5) pass the "mem=4M" option to the kernel (thereby disabling
1278 all but the first 4 MB of RAM)
1279 6) make sure that the CPU is not over clocked.
1280 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1281 8) disable the cache from your BIOS settings
1282 9) install a fan for the video card or exchange video RAM
1283 10) install a better fan for the CPU
1284 11) exchange RAM chips
1285 12) exchange the motherboard.
1287 To compile this driver as a module, choose M here: the
1288 module will be called apm.
1292 config APM_IGNORE_USER_SUSPEND
1293 bool "Ignore USER SUSPEND"
1295 This option will ignore USER SUSPEND requests. On machines with a
1296 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1297 series notebooks, it is necessary to say Y because of a BIOS bug.
1299 config APM_DO_ENABLE
1300 bool "Enable PM at boot time"
1302 Enable APM features at boot time. From page 36 of the APM BIOS
1303 specification: "When disabled, the APM BIOS does not automatically
1304 power manage devices, enter the Standby State, enter the Suspend
1305 State, or take power saving steps in response to CPU Idle calls."
1306 This driver will make CPU Idle calls when Linux is idle (unless this
1307 feature is turned off -- see "Do CPU IDLE calls", below). This
1308 should always save battery power, but more complicated APM features
1309 will be dependent on your BIOS implementation. You may need to turn
1310 this option off if your computer hangs at boot time when using APM
1311 support, or if it beeps continuously instead of suspending. Turn
1312 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1313 T400CDT. This is off by default since most machines do fine without
1317 bool "Make CPU Idle calls when idle"
1319 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1320 On some machines, this can activate improved power savings, such as
1321 a slowed CPU clock rate, when the machine is idle. These idle calls
1322 are made after the idle loop has run for some length of time (e.g.,
1323 333 mS). On some machines, this will cause a hang at boot time or
1324 whenever the CPU becomes idle. (On machines with more than one CPU,
1325 this option does nothing.)
1327 config APM_DISPLAY_BLANK
1328 bool "Enable console blanking using APM"
1330 Enable console blanking using the APM. Some laptops can use this to
1331 turn off the LCD backlight when the screen blanker of the Linux
1332 virtual console blanks the screen. Note that this is only used by
1333 the virtual console screen blanker, and won't turn off the backlight
1334 when using the X Window system. This also doesn't have anything to
1335 do with your VESA-compliant power-saving monitor. Further, this
1336 option doesn't work for all laptops -- it might not turn off your
1337 backlight at all, or it might print a lot of errors to the console,
1338 especially if you are using gpm.
1340 config APM_ALLOW_INTS
1341 bool "Allow interrupts during APM BIOS calls"
1343 Normally we disable external interrupts while we are making calls to
1344 the APM BIOS as a measure to lessen the effects of a badly behaving
1345 BIOS implementation. The BIOS should reenable interrupts if it
1346 needs to. Unfortunately, some BIOSes do not -- especially those in
1347 many of the newer IBM Thinkpads. If you experience hangs when you
1348 suspend, try setting this to Y. Otherwise, say N.
1350 config APM_REAL_MODE_POWER_OFF
1351 bool "Use real mode APM BIOS call to power off"
1353 Use real mode APM BIOS calls to switch off the computer. This is
1354 a work-around for a number of buggy BIOSes. Switch this option on if
1355 your computer crashes instead of powering off properly.
1359 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1361 source "drivers/cpuidle/Kconfig"
1366 menu "Bus options (PCI etc.)"
1369 bool "PCI support" if !X86_VISWS
1370 depends on !X86_VOYAGER
1372 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1374 Find out whether you have a PCI motherboard. PCI is the name of a
1375 bus system, i.e. the way the CPU talks to the other stuff inside
1376 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1377 VESA. If you have PCI, say Y, otherwise N.
1380 prompt "PCI access mode"
1381 depends on X86_32 && PCI && !X86_VISWS
1384 On PCI systems, the BIOS can be used to detect the PCI devices and
1385 determine their configuration. However, some old PCI motherboards
1386 have BIOS bugs and may crash if this is done. Also, some embedded
1387 PCI-based systems don't have any BIOS at all. Linux can also try to
1388 detect the PCI hardware directly without using the BIOS.
1390 With this option, you can specify how Linux should detect the
1391 PCI devices. If you choose "BIOS", the BIOS will be used,
1392 if you choose "Direct", the BIOS won't be used, and if you
1393 choose "MMConfig", then PCI Express MMCONFIG will be used.
1394 If you choose "Any", the kernel will try MMCONFIG, then the
1395 direct access method and falls back to the BIOS if that doesn't
1396 work. If unsure, go with the default, which is "Any".
1401 config PCI_GOMMCONFIG
1414 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1416 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1419 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1423 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1430 bool "Support mmconfig PCI config space access"
1431 depends on X86_64 && PCI && ACPI
1434 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1435 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1437 DMA remapping (DMAR) devices support enables independent address
1438 translations for Direct Memory Access (DMA) from devices.
1439 These DMA remapping devices are reported via ACPI tables
1440 and include PCI device scope covered by these DMA
1445 prompt "Support for Graphics workaround"
1448 Current Graphics drivers tend to use physical address
1449 for DMA and avoid using DMA APIs. Setting this config
1450 option permits the IOMMU driver to set a unity map for
1451 all the OS-visible memory. Hence the driver can continue
1452 to use physical addresses for DMA.
1454 config DMAR_FLOPPY_WA
1458 Floppy disk drivers are know to bypass DMA API calls
1459 thereby failing to work when IOMMU is enabled. This
1460 workaround will setup a 1:1 mapping for the first
1461 16M to make floppy (an ISA device) work.
1463 source "drivers/pci/pcie/Kconfig"
1465 source "drivers/pci/Kconfig"
1467 # x86_64 have no ISA slots, but do have ISA-style DMA.
1475 depends on !(X86_VOYAGER || X86_VISWS)
1477 Find out whether you have ISA slots on your motherboard. ISA is the
1478 name of a bus system, i.e. the way the CPU talks to the other stuff
1479 inside your box. Other bus systems are PCI, EISA, MicroChannel
1480 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1481 newer boards don't support it. If you have ISA, say Y, otherwise N.
1487 The Extended Industry Standard Architecture (EISA) bus was
1488 developed as an open alternative to the IBM MicroChannel bus.
1490 The EISA bus provided some of the features of the IBM MicroChannel
1491 bus while maintaining backward compatibility with cards made for
1492 the older ISA bus. The EISA bus saw limited use between 1988 and
1493 1995 when it was made obsolete by the PCI bus.
1495 Say Y here if you are building a kernel for an EISA-based machine.
1499 source "drivers/eisa/Kconfig"
1502 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1503 default y if X86_VOYAGER
1505 MicroChannel Architecture is found in some IBM PS/2 machines and
1506 laptops. It is a bus system similar to PCI or ISA. See
1507 <file:Documentation/mca.txt> (and especially the web page given
1508 there) before attempting to build an MCA bus kernel.
1510 source "drivers/mca/Kconfig"
1513 tristate "NatSemi SCx200 support"
1514 depends on !X86_VOYAGER
1516 This provides basic support for National Semiconductor's
1517 (now AMD's) Geode processors. The driver probes for the
1518 PCI-IDs of several on-chip devices, so its a good dependency
1519 for other scx200_* drivers.
1521 If compiled as a module, the driver is named scx200.
1523 config SCx200HR_TIMER
1524 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1525 depends on SCx200 && GENERIC_TIME
1528 This driver provides a clocksource built upon the on-chip
1529 27MHz high-resolution timer. Its also a workaround for
1530 NSC Geode SC-1100's buggy TSC, which loses time when the
1531 processor goes idle (as is done by the scheduler). The
1532 other workaround is idle=poll boot option.
1534 config GEODE_MFGPT_TIMER
1536 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1537 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1539 This driver provides a clock event source based on the MFGPT
1540 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1541 MFGPTs have a better resolution and max interval than the
1542 generic PIT, and are suitable for use as high-res timers.
1548 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1550 source "drivers/pcmcia/Kconfig"
1552 source "drivers/pci/hotplug/Kconfig"
1557 menu "Executable file formats / Emulations"
1559 source "fs/Kconfig.binfmt"
1561 config IA32_EMULATION
1562 bool "IA32 Emulation"
1564 select COMPAT_BINFMT_ELF
1566 Include code to run 32-bit programs under a 64-bit kernel. You should
1567 likely turn this on, unless you're 100% sure that you don't have any
1568 32-bit programs left.
1571 tristate "IA32 a.out support"
1572 depends on IA32_EMULATION
1574 Support old a.out binaries in the 32bit emulation.
1578 depends on IA32_EMULATION
1580 config COMPAT_FOR_U64_ALIGNMENT
1584 config SYSVIPC_COMPAT
1586 depends on X86_64 && COMPAT && SYSVIPC
1591 source "net/Kconfig"
1593 source "drivers/Kconfig"
1595 source "drivers/firmware/Kconfig"
1599 source "kernel/Kconfig.instrumentation"
1601 source "arch/x86/Kconfig.debug"
1603 source "security/Kconfig"
1605 source "crypto/Kconfig"
1607 source "arch/x86/kvm/Kconfig"
1609 source "lib/Kconfig"