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 SEMAPHORE_SLEEPERS
62 config GENERIC_ISA_DMA
72 config GENERIC_HWEIGHT
78 config ARCH_MAY_HAVE_PC_FDC
84 config RWSEM_GENERIC_SPINLOCK
87 config RWSEM_XCHGADD_ALGORITHM
90 config ARCH_HAS_ILOG2_U32
93 config ARCH_HAS_ILOG2_U64
96 config GENERIC_CALIBRATE_DELAY
99 config GENERIC_TIME_VSYSCALL
103 config HAVE_SETUP_PER_CPU_AREA
106 config ARCH_SUPPORTS_OPROFILE
116 config ARCH_POPULATES_NODE_MAP
123 # Use the generic interrupt handling code in kernel/irq/:
124 config GENERIC_HARDIRQS
128 config GENERIC_IRQ_PROBE
132 config GENERIC_PENDING_IRQ
134 depends on GENERIC_HARDIRQS && SMP
139 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
144 depends on X86_32 && SMP
148 depends on X86_64 && SMP
153 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8)
156 config X86_BIOS_REBOOT
158 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
161 config X86_TRAMPOLINE
163 depends on X86_SMP || (X86_VOYAGER && SMP)
168 source "init/Kconfig"
170 menu "Processor type and features"
172 source "kernel/time/Kconfig"
175 bool "Symmetric multi-processing support"
177 This enables support for systems with more than one CPU. If you have
178 a system with only one CPU, like most personal computers, say N. If
179 you have a system with more than one CPU, say Y.
181 If you say N here, the kernel will run on single and multiprocessor
182 machines, but will use only one CPU of a multiprocessor machine. If
183 you say Y here, the kernel will run on many, but not all,
184 singleprocessor machines. On a singleprocessor machine, the kernel
185 will run faster if you say N here.
187 Note that if you say Y here and choose architecture "586" or
188 "Pentium" under "Processor family", the kernel will not work on 486
189 architectures. Similarly, multiprocessor kernels for the "PPro"
190 architecture may not work on all Pentium based boards.
192 People using multiprocessor machines who say Y here should also say
193 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
194 Management" code will be disabled if you say Y here.
196 See also the <file:Documentation/smp.txt>,
197 <file:Documentation/i386/IO-APIC.txt>,
198 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
199 <http://www.tldp.org/docs.html#howto>.
201 If you don't know what to do here, say N.
204 prompt "Subarchitecture Type"
210 Choose this option if your computer is a standard PC or compatible.
216 Select this for an AMD Elan processor.
218 Do not use this option for K6/Athlon/Opteron processors!
220 If unsure, choose "PC-compatible" instead.
225 select SMP if !BROKEN
227 Voyager is an MCA-based 32-way capable SMP architecture proprietary
228 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
232 If you do not specifically know you have a Voyager based machine,
233 say N here, otherwise the kernel you build will not be bootable.
236 bool "NUMAQ (IBM/Sequent)"
241 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
242 multiquad box. This changes the way that processors are bootstrapped,
243 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
244 You will need a new lynxer.elf file to flash your firmware with - send
245 email to <Martin.Bligh@us.ibm.com>.
248 bool "Summit/EXA (IBM x440)"
249 depends on X86_32 && SMP
251 This option is needed for IBM systems that use the Summit/EXA chipset.
252 In particular, it is needed for the x440.
254 If you don't have one of these computers, you should say N here.
255 If you want to build a NUMA kernel, you must select ACPI.
258 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
259 depends on X86_32 && SMP
261 This option is needed for the systems that have more than 8 CPUs
262 and if the system is not of any sub-arch type above.
264 If you don't have such a system, you should say N here.
267 bool "SGI 320/540 (Visual Workstation)"
270 The SGI Visual Workstation series is an IA32-based workstation
271 based on SGI systems chips with some legacy PC hardware attached.
273 Say Y here to create a kernel to run on the SGI 320 or 540.
275 A kernel compiled for the Visual Workstation will not run on PCs
276 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
278 config X86_GENERICARCH
279 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
282 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
283 It is intended for a generic binary kernel.
284 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
287 bool "Support for Unisys ES7000 IA32 series"
288 depends on X86_32 && SMP
290 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
291 supposed to run on an IA32-based Unisys ES7000 system.
292 Only choose this option if you have such a system, otherwise you
296 bool "RDC R-321x SoC"
299 select X86_REBOOTFIXUPS
303 This option is needed for RDC R-321x system-on-chip, also known
305 If you don't have one of these chips, you should say N here.
308 bool "Support for ScaleMP vSMP"
309 depends on X86_64 && PCI
311 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
312 supposed to run on these EM64T-based machines. Only choose this option
313 if you have one of these machines.
317 config SCHED_NO_NO_OMIT_FRAME_POINTER
319 prompt "Single-depth WCHAN output"
322 Calculate simpler /proc/<PID>/wchan values. If this option
323 is disabled then wchan values will recurse back to the
324 caller function. This provides more accurate wchan values,
325 at the expense of slightly more scheduling overhead.
327 If in doubt, say "Y".
329 menuconfig PARAVIRT_GUEST
330 bool "Paravirtualized guest support"
332 Say Y here to get to see options related to running Linux under
333 various hypervisors. This option alone does not add any kernel code.
335 If you say N, all options in this submenu will be skipped and disabled.
339 source "arch/x86/xen/Kconfig"
342 bool "VMI Guest support"
345 depends on !(X86_VISWS || X86_VOYAGER)
347 VMI provides a paravirtualized interface to the VMware ESX server
348 (it could be used by other hypervisors in theory too, but is not
349 at the moment), by linking the kernel to a GPL-ed ROM module
350 provided by the hypervisor.
352 source "arch/x86/lguest/Kconfig"
355 bool "Enable paravirtualization code"
356 depends on !(X86_VISWS || X86_VOYAGER)
358 This changes the kernel so it can modify itself when it is run
359 under a hypervisor, potentially improving performance significantly
360 over full virtualization. However, when run without a hypervisor
361 the kernel is theoretically slower and slightly larger.
367 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
370 config HAVE_ARCH_PARSE_SRAT
374 config X86_SUMMIT_NUMA
376 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
378 config X86_CYCLONE_TIMER
380 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
382 config ES7000_CLUSTERED_APIC
384 depends on SMP && X86_ES7000 && MPENTIUMIII
386 source "arch/x86/Kconfig.cpu"
390 prompt "HPET Timer Support" if X86_32
392 Use the IA-PC HPET (High Precision Event Timer) to manage
393 time in preference to the PIT and RTC, if a HPET is
395 HPET is the next generation timer replacing legacy 8254s.
396 The HPET provides a stable time base on SMP
397 systems, unlike the TSC, but it is more expensive to access,
398 as it is off-chip. You can find the HPET spec at
399 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
401 You can safely choose Y here. However, HPET will only be
402 activated if the platform and the BIOS support this feature.
403 Otherwise the 8254 will be used for timing services.
405 Choose N to continue using the legacy 8254 timer.
407 config HPET_EMULATE_RTC
409 depends on HPET_TIMER && (RTC=y || RTC=m)
411 # Mark as embedded because too many people got it wrong.
412 # The code disables itself when not needed.
414 bool "GART IOMMU support" if EMBEDDED
418 depends on X86_64 && PCI
420 Support for full DMA access of devices with 32bit memory access only
421 on systems with more than 3GB. This is usually needed for USB,
422 sound, many IDE/SATA chipsets and some other devices.
423 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
424 based hardware IOMMU and a software bounce buffer based IOMMU used
425 on Intel systems and as fallback.
426 The code is only active when needed (enough memory and limited
427 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
431 bool "IBM Calgary IOMMU support"
433 depends on X86_64 && PCI && EXPERIMENTAL
435 Support for hardware IOMMUs in IBM's xSeries x366 and x460
436 systems. Needed to run systems with more than 3GB of memory
437 properly with 32-bit PCI devices that do not support DAC
438 (Double Address Cycle). Calgary also supports bus level
439 isolation, where all DMAs pass through the IOMMU. This
440 prevents them from going anywhere except their intended
441 destination. This catches hard-to-find kernel bugs and
442 mis-behaving drivers and devices that do not use the DMA-API
443 properly to set up their DMA buffers. The IOMMU can be
444 turned off at boot time with the iommu=off parameter.
445 Normally the kernel will make the right choice by itself.
448 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
450 prompt "Should Calgary be enabled by default?"
451 depends on CALGARY_IOMMU
453 Should Calgary be enabled by default? if you choose 'y', Calgary
454 will be used (if it exists). If you choose 'n', Calgary will not be
455 used even if it exists. If you choose 'n' and would like to use
456 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
459 # need this always selected by IOMMU for the VIA workaround
463 Support for software bounce buffers used on x86-64 systems
464 which don't have a hardware IOMMU (e.g. the current generation
465 of Intel's x86-64 CPUs). Using this PCI devices which can only
466 access 32-bits of memory can be used on systems with more than
467 3 GB of memory. If unsure, say Y.
471 int "Maximum number of CPUs (2-255)"
474 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
477 This allows you to specify the maximum number of CPUs which this
478 kernel will support. The maximum supported value is 255 and the
479 minimum value which makes sense is 2.
481 This is purely to save memory - each supported CPU adds
482 approximately eight kilobytes to the kernel image.
485 bool "SMT (Hyperthreading) scheduler support"
486 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
488 SMT scheduler support improves the CPU scheduler's decision making
489 when dealing with Intel Pentium 4 chips with HyperThreading at a
490 cost of slightly increased overhead in some places. If unsure say
495 prompt "Multi-core scheduler support"
496 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
498 Multi-core scheduler support improves the CPU scheduler's decision
499 making when dealing with multi-core CPU chips at a cost of slightly
500 increased overhead in some places. If unsure say N here.
502 source "kernel/Kconfig.preempt"
505 bool "Local APIC support on uniprocessors"
506 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
508 A local APIC (Advanced Programmable Interrupt Controller) is an
509 integrated interrupt controller in the CPU. If you have a single-CPU
510 system which has a processor with a local APIC, you can say Y here to
511 enable and use it. If you say Y here even though your machine doesn't
512 have a local APIC, then the kernel will still run with no slowdown at
513 all. The local APIC supports CPU-generated self-interrupts (timer,
514 performance counters), and the NMI watchdog which detects hard
518 bool "IO-APIC support on uniprocessors"
519 depends on X86_UP_APIC
521 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
522 SMP-capable replacement for PC-style interrupt controllers. Most
523 SMP systems and many recent uniprocessor systems have one.
525 If you have a single-CPU system with an IO-APIC, you can say Y here
526 to use it. If you say Y here even though your machine doesn't have
527 an IO-APIC, then the kernel will still run with no slowdown at all.
529 config X86_LOCAL_APIC
531 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
535 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
537 config X86_VISWS_APIC
539 depends on X86_32 && X86_VISWS
542 bool "Machine Check Exception"
543 depends on !X86_VOYAGER
545 Machine Check Exception support allows the processor to notify the
546 kernel if it detects a problem (e.g. overheating, component failure).
547 The action the kernel takes depends on the severity of the problem,
548 ranging from a warning message on the console, to halting the machine.
549 Your processor must be a Pentium or newer to support this - check the
550 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
551 have a design flaw which leads to false MCE events - hence MCE is
552 disabled on all P5 processors, unless explicitly enabled with "mce"
553 as a boot argument. Similarly, if MCE is built in and creates a
554 problem on some new non-standard machine, you can boot with "nomce"
555 to disable it. MCE support simply ignores non-MCE processors like
556 the 386 and 486, so nearly everyone can say Y here.
560 prompt "Intel MCE features"
561 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
563 Additional support for intel specific MCE features such as
568 prompt "AMD MCE features"
569 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
571 Additional support for AMD specific MCE features such as
572 the DRAM Error Threshold.
574 config X86_MCE_NONFATAL
575 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
576 depends on X86_32 && X86_MCE
578 Enabling this feature starts a timer that triggers every 5 seconds which
579 will look at the machine check registers to see if anything happened.
580 Non-fatal problems automatically get corrected (but still logged).
581 Disable this if you don't want to see these messages.
582 Seeing the messages this option prints out may be indicative of dying
583 or out-of-spec (ie, overclocked) hardware.
584 This option only does something on certain CPUs.
585 (AMD Athlon/Duron and Intel Pentium 4)
587 config X86_MCE_P4THERMAL
588 bool "check for P4 thermal throttling interrupt."
589 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
591 Enabling this feature will cause a message to be printed when the P4
592 enters thermal throttling.
595 bool "Enable VM86 support" if EMBEDDED
599 This option is required by programs like DOSEMU to run 16-bit legacy
600 code on X86 processors. It also may be needed by software like
601 XFree86 to initialize some video cards via BIOS. Disabling this
602 option saves about 6k.
605 tristate "Toshiba Laptop support"
608 This adds a driver to safely access the System Management Mode of
609 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
610 not work on models with a Phoenix BIOS. The System Management Mode
611 is used to set the BIOS and power saving options on Toshiba portables.
613 For information on utilities to make use of this driver see the
614 Toshiba Linux utilities web site at:
615 <http://www.buzzard.org.uk/toshiba/>.
617 Say Y if you intend to run this kernel on a Toshiba portable.
621 tristate "Dell laptop support"
624 This adds a driver to safely access the System Management Mode
625 of the CPU on the Dell Inspiron 8000. The System Management Mode
626 is used to read cpu temperature and cooling fan status and to
627 control the fans on the I8K portables.
629 This driver has been tested only on the Inspiron 8000 but it may
630 also work with other Dell laptops. You can force loading on other
631 models by passing the parameter `force=1' to the module. Use at
634 For information on utilities to make use of this driver see the
635 I8K Linux utilities web site at:
636 <http://people.debian.org/~dz/i8k/>
638 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
641 config X86_REBOOTFIXUPS
643 prompt "Enable X86 board specific fixups for reboot"
644 depends on X86_32 && X86
646 This enables chipset and/or board specific fixups to be done
647 in order to get reboot to work correctly. This is only needed on
648 some combinations of hardware and BIOS. The symptom, for which
649 this config is intended, is when reboot ends with a stalled/hung
652 Currently, the only fixup is for the Geode machines using
653 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
655 Say Y if you want to enable the fixup. Currently, it's safe to
656 enable this option even if you don't need it.
660 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
663 If you say Y here, you will be able to update the microcode on
664 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
665 Pentium III, Pentium 4, Xeon etc. You will obviously need the
666 actual microcode binary data itself which is not shipped with the
669 For latest news and information on obtaining all the required
670 ingredients for this driver, check:
671 <http://www.urbanmyth.org/microcode/>.
673 To compile this driver as a module, choose M here: the
674 module will be called microcode.
676 config MICROCODE_OLD_INTERFACE
681 tristate "/dev/cpu/*/msr - Model-specific register support"
683 This device gives privileged processes access to the x86
684 Model-Specific Registers (MSRs). It is a character device with
685 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
686 MSR accesses are directed to a specific CPU on multi-processor
690 tristate "/dev/cpu/*/cpuid - CPU information support"
692 This device gives processes access to the x86 CPUID instruction to
693 be executed on a specific processor. It is a character device
694 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
698 prompt "High Memory Support"
699 default HIGHMEM4G if !X86_NUMAQ
700 default HIGHMEM64G if X86_NUMAQ
705 depends on !X86_NUMAQ
707 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
708 However, the address space of 32-bit x86 processors is only 4
709 Gigabytes large. That means that, if you have a large amount of
710 physical memory, not all of it can be "permanently mapped" by the
711 kernel. The physical memory that's not permanently mapped is called
714 If you are compiling a kernel which will never run on a machine with
715 more than 1 Gigabyte total physical RAM, answer "off" here (default
716 choice and suitable for most users). This will result in a "3GB/1GB"
717 split: 3GB are mapped so that each process sees a 3GB virtual memory
718 space and the remaining part of the 4GB virtual memory space is used
719 by the kernel to permanently map as much physical memory as
722 If the machine has between 1 and 4 Gigabytes physical RAM, then
725 If more than 4 Gigabytes is used then answer "64GB" here. This
726 selection turns Intel PAE (Physical Address Extension) mode on.
727 PAE implements 3-level paging on IA32 processors. PAE is fully
728 supported by Linux, PAE mode is implemented on all recent Intel
729 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
730 then the kernel will not boot on CPUs that don't support PAE!
732 The actual amount of total physical memory will either be
733 auto detected or can be forced by using a kernel command line option
734 such as "mem=256M". (Try "man bootparam" or see the documentation of
735 your boot loader (lilo or loadlin) about how to pass options to the
736 kernel at boot time.)
738 If unsure, say "off".
742 depends on !X86_NUMAQ
744 Select this if you have a 32-bit processor and between 1 and 4
745 gigabytes of physical RAM.
749 depends on !M386 && !M486
752 Select this if you have a 32-bit processor and more than 4
753 gigabytes of physical RAM.
758 depends on EXPERIMENTAL
759 prompt "Memory split" if EMBEDDED
763 Select the desired split between kernel and user memory.
765 If the address range available to the kernel is less than the
766 physical memory installed, the remaining memory will be available
767 as "high memory". Accessing high memory is a little more costly
768 than low memory, as it needs to be mapped into the kernel first.
769 Note that increasing the kernel address space limits the range
770 available to user programs, making the address space there
771 tighter. Selecting anything other than the default 3G/1G split
772 will also likely make your kernel incompatible with binary-only
775 If you are not absolutely sure what you are doing, leave this
779 bool "3G/1G user/kernel split"
780 config VMSPLIT_3G_OPT
782 bool "3G/1G user/kernel split (for full 1G low memory)"
784 bool "2G/2G user/kernel split"
785 config VMSPLIT_2G_OPT
787 bool "2G/2G user/kernel split (for full 2G low memory)"
789 bool "1G/3G user/kernel split"
794 default 0xB0000000 if VMSPLIT_3G_OPT
795 default 0x80000000 if VMSPLIT_2G
796 default 0x78000000 if VMSPLIT_2G_OPT
797 default 0x40000000 if VMSPLIT_1G
803 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
807 prompt "PAE (Physical Address Extension) Support"
808 depends on X86_32 && !HIGHMEM4G
809 select RESOURCES_64BIT
811 PAE is required for NX support, and furthermore enables
812 larger swapspace support for non-overcommit purposes. It
813 has the cost of more pagetable lookup overhead, and also
814 consumes more pagetable space per process.
816 # Common NUMA Features
818 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
820 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
822 default y if (X86_NUMAQ || X86_SUMMIT)
824 Enable NUMA (Non Uniform Memory Access) support.
825 The kernel will try to allocate memory used by a CPU on the
826 local memory controller of the CPU and add some more
827 NUMA awareness to the kernel.
829 For i386 this is currently highly experimental and should be only
830 used for kernel development. It might also cause boot failures.
831 For x86_64 this is recommended on all multiprocessor Opteron systems.
832 If the system is EM64T, you should say N unless your system is
835 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
836 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
840 prompt "Old style AMD Opteron NUMA detection"
841 depends on X86_64 && NUMA && PCI
843 Enable K8 NUMA node topology detection. You should say Y here if
844 you have a multi processor AMD K8 system. This uses an old
845 method to read the NUMA configuration directly from the builtin
846 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
847 instead, which also takes priority if both are compiled in.
849 config X86_64_ACPI_NUMA
851 prompt "ACPI NUMA detection"
852 depends on X86_64 && NUMA && ACPI && PCI
855 Enable ACPI SRAT based node topology detection.
858 bool "NUMA emulation"
859 depends on X86_64 && NUMA
861 Enable NUMA emulation. A flat machine will be split
862 into virtual nodes when booted with "numa=fake=N", where N is the
863 number of nodes. This is only useful for debugging.
868 default "6" if X86_64
869 default "4" if X86_NUMAQ
871 depends on NEED_MULTIPLE_NODES
873 config HAVE_ARCH_BOOTMEM_NODE
875 depends on X86_32 && NUMA
877 config ARCH_HAVE_MEMORY_PRESENT
879 depends on X86_32 && DISCONTIGMEM
881 config NEED_NODE_MEMMAP_SIZE
883 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
885 config HAVE_ARCH_ALLOC_REMAP
887 depends on X86_32 && NUMA
889 config ARCH_FLATMEM_ENABLE
891 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
893 config ARCH_DISCONTIGMEM_ENABLE
895 depends on NUMA && X86_32
897 config ARCH_DISCONTIGMEM_DEFAULT
899 depends on NUMA && X86_32
901 config ARCH_SPARSEMEM_DEFAULT
905 config ARCH_SPARSEMEM_ENABLE
907 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
908 select SPARSEMEM_STATIC if X86_32
909 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
911 config ARCH_SELECT_MEMORY_MODEL
913 depends on ARCH_SPARSEMEM_ENABLE
915 config ARCH_MEMORY_PROBE
917 depends on MEMORY_HOTPLUG
922 bool "Allocate 3rd-level pagetables from highmem"
923 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
925 The VM uses one page table entry for each page of physical memory.
926 For systems with a lot of RAM, this can be wasteful of precious
927 low memory. Setting this option will put user-space page table
928 entries in high memory.
930 config MATH_EMULATION
932 prompt "Math emulation" if X86_32
934 Linux can emulate a math coprocessor (used for floating point
935 operations) if you don't have one. 486DX and Pentium processors have
936 a math coprocessor built in, 486SX and 386 do not, unless you added
937 a 487DX or 387, respectively. (The messages during boot time can
938 give you some hints here ["man dmesg"].) Everyone needs either a
939 coprocessor or this emulation.
941 If you don't have a math coprocessor, you need to say Y here; if you
942 say Y here even though you have a coprocessor, the coprocessor will
943 be used nevertheless. (This behavior can be changed with the kernel
944 command line option "no387", which comes handy if your coprocessor
945 is broken. Try "man bootparam" or see the documentation of your boot
946 loader (lilo or loadlin) about how to pass options to the kernel at
947 boot time.) This means that it is a good idea to say Y here if you
948 intend to use this kernel on different machines.
950 More information about the internals of the Linux math coprocessor
951 emulation can be found in <file:arch/x86/math-emu/README>.
953 If you are not sure, say Y; apart from resulting in a 66 KB bigger
954 kernel, it won't hurt.
957 bool "MTRR (Memory Type Range Register) support"
959 On Intel P6 family processors (Pentium Pro, Pentium II and later)
960 the Memory Type Range Registers (MTRRs) may be used to control
961 processor access to memory ranges. This is most useful if you have
962 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
963 allows bus write transfers to be combined into a larger transfer
964 before bursting over the PCI/AGP bus. This can increase performance
965 of image write operations 2.5 times or more. Saying Y here creates a
966 /proc/mtrr file which may be used to manipulate your processor's
967 MTRRs. Typically the X server should use this.
969 This code has a reasonably generic interface so that similar
970 control registers on other processors can be easily supported
973 The Cyrix 6x86, 6x86MX and M II processors have Address Range
974 Registers (ARRs) which provide a similar functionality to MTRRs. For
975 these, the ARRs are used to emulate the MTRRs.
976 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
977 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
978 write-combining. All of these processors are supported by this code
979 and it makes sense to say Y here if you have one of them.
981 Saying Y here also fixes a problem with buggy SMP BIOSes which only
982 set the MTRRs for the boot CPU and not for the secondary CPUs. This
983 can lead to all sorts of problems, so it's good to say Y here.
985 You can safely say Y even if your machine doesn't have MTRRs, you'll
986 just add about 9 KB to your kernel.
988 See <file:Documentation/mtrr.txt> for more information.
992 prompt "EFI runtime service support"
995 This enables the kernel to use EFI runtime services that are
996 available (such as the EFI variable services).
998 This option is only useful on systems that have EFI firmware.
999 In addition, you should use the latest ELILO loader available
1000 at <http://elilo.sourceforge.net> in order to take advantage
1001 of EFI runtime services. However, even with this option, the
1002 resultant kernel should continue to boot on existing non-EFI
1007 prompt "Enable kernel irq balancing"
1008 depends on X86_32 && SMP && X86_IO_APIC
1010 The default yes will allow the kernel to do irq load balancing.
1011 Saying no will keep the kernel from doing irq load balancing.
1015 prompt "Enable seccomp to safely compute untrusted bytecode"
1018 This kernel feature is useful for number crunching applications
1019 that may need to compute untrusted bytecode during their
1020 execution. By using pipes or other transports made available to
1021 the process as file descriptors supporting the read/write
1022 syscalls, it's possible to isolate those applications in
1023 their own address space using seccomp. Once seccomp is
1024 enabled via /proc/<pid>/seccomp, it cannot be disabled
1025 and the task is only allowed to execute a few safe syscalls
1026 defined by each seccomp mode.
1028 If unsure, say Y. Only embedded should say N here.
1030 config CC_STACKPROTECTOR
1031 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1032 depends on X86_64 && EXPERIMENTAL
1034 This option turns on the -fstack-protector GCC feature. This
1035 feature puts, at the beginning of critical functions, a canary
1036 value on the stack just before the return address, and validates
1037 the value just before actually returning. Stack based buffer
1038 overflows (that need to overwrite this return address) now also
1039 overwrite the canary, which gets detected and the attack is then
1040 neutralized via a kernel panic.
1042 This feature requires gcc version 4.2 or above, or a distribution
1043 gcc with the feature backported. Older versions are automatically
1044 detected and for those versions, this configuration option is ignored.
1046 config CC_STACKPROTECTOR_ALL
1047 bool "Use stack-protector for all functions"
1048 depends on CC_STACKPROTECTOR
1050 Normally, GCC only inserts the canary value protection for
1051 functions that use large-ish on-stack buffers. By enabling
1052 this option, GCC will be asked to do this for ALL functions.
1054 source kernel/Kconfig.hz
1057 bool "kexec system call"
1059 kexec is a system call that implements the ability to shutdown your
1060 current kernel, and to start another kernel. It is like a reboot
1061 but it is independent of the system firmware. And like a reboot
1062 you can start any kernel with it, not just Linux.
1064 The name comes from the similarity to the exec system call.
1066 It is an ongoing process to be certain the hardware in a machine
1067 is properly shutdown, so do not be surprised if this code does not
1068 initially work for you. It may help to enable device hotplugging
1069 support. As of this writing the exact hardware interface is
1070 strongly in flux, so no good recommendation can be made.
1073 bool "kernel crash dumps (EXPERIMENTAL)"
1074 depends on EXPERIMENTAL
1075 depends on X86_64 || (X86_32 && HIGHMEM)
1077 Generate crash dump after being started by kexec.
1078 This should be normally only set in special crash dump kernels
1079 which are loaded in the main kernel with kexec-tools into
1080 a specially reserved region and then later executed after
1081 a crash by kdump/kexec. The crash dump kernel must be compiled
1082 to a memory address not used by the main kernel or BIOS using
1083 PHYSICAL_START, or it must be built as a relocatable image
1084 (CONFIG_RELOCATABLE=y).
1085 For more details see Documentation/kdump/kdump.txt
1087 config PHYSICAL_START
1088 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1089 default "0x1000000" if X86_NUMAQ
1090 default "0x200000" if X86_64
1093 This gives the physical address where the kernel is loaded.
1095 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1096 bzImage will decompress itself to above physical address and
1097 run from there. Otherwise, bzImage will run from the address where
1098 it has been loaded by the boot loader and will ignore above physical
1101 In normal kdump cases one does not have to set/change this option
1102 as now bzImage can be compiled as a completely relocatable image
1103 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1104 address. This option is mainly useful for the folks who don't want
1105 to use a bzImage for capturing the crash dump and want to use a
1106 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1107 to be specifically compiled to run from a specific memory area
1108 (normally a reserved region) and this option comes handy.
1110 So if you are using bzImage for capturing the crash dump, leave
1111 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1112 Otherwise if you plan to use vmlinux for capturing the crash dump
1113 change this value to start of the reserved region (Typically 16MB
1114 0x1000000). In other words, it can be set based on the "X" value as
1115 specified in the "crashkernel=YM@XM" command line boot parameter
1116 passed to the panic-ed kernel. Typically this parameter is set as
1117 crashkernel=64M@16M. Please take a look at
1118 Documentation/kdump/kdump.txt for more details about crash dumps.
1120 Usage of bzImage for capturing the crash dump is recommended as
1121 one does not have to build two kernels. Same kernel can be used
1122 as production kernel and capture kernel. Above option should have
1123 gone away after relocatable bzImage support is introduced. But it
1124 is present because there are users out there who continue to use
1125 vmlinux for dump capture. This option should go away down the
1128 Don't change this unless you know what you are doing.
1131 bool "Build a relocatable kernel (EXPERIMENTAL)"
1132 depends on EXPERIMENTAL
1134 This builds a kernel image that retains relocation information
1135 so it can be loaded someplace besides the default 1MB.
1136 The relocations tend to make the kernel binary about 10% larger,
1137 but are discarded at runtime.
1139 One use is for the kexec on panic case where the recovery kernel
1140 must live at a different physical address than the primary
1143 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1144 it has been loaded at and the compile time physical address
1145 (CONFIG_PHYSICAL_START) is ignored.
1147 config PHYSICAL_ALIGN
1149 prompt "Alignment value to which kernel should be aligned" if X86_32
1150 default "0x100000" if X86_32
1151 default "0x200000" if X86_64
1152 range 0x2000 0x400000
1154 This value puts the alignment restrictions on physical address
1155 where kernel is loaded and run from. Kernel is compiled for an
1156 address which meets above alignment restriction.
1158 If bootloader loads the kernel at a non-aligned address and
1159 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1160 address aligned to above value and run from there.
1162 If bootloader loads the kernel at a non-aligned address and
1163 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1164 load address and decompress itself to the address it has been
1165 compiled for and run from there. The address for which kernel is
1166 compiled already meets above alignment restrictions. Hence the
1167 end result is that kernel runs from a physical address meeting
1168 above alignment restrictions.
1170 Don't change this unless you know what you are doing.
1173 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1174 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1176 Say Y here to experiment with turning CPUs off and on, and to
1177 enable suspend on SMP systems. CPUs can be controlled through
1178 /sys/devices/system/cpu.
1179 Say N if you want to disable CPU hotplug and don't need to
1184 prompt "Compat VDSO support"
1185 depends on X86_32 || IA32_EMULATION
1187 Map the 32-bit VDSO to the predictable old-style address too.
1189 Say N here if you are running a sufficiently recent glibc
1190 version (2.3.3 or later), to remove the high-mapped
1191 VDSO mapping and to exclusively use the randomized VDSO.
1197 config ARCH_ENABLE_MEMORY_HOTPLUG
1199 depends on X86_64 || (X86_32 && HIGHMEM)
1201 config HAVE_ARCH_EARLY_PFN_TO_NID
1205 menu "Power management options"
1206 depends on !X86_VOYAGER
1208 config ARCH_HIBERNATION_HEADER
1210 depends on X86_64 && HIBERNATION
1212 source "kernel/power/Kconfig"
1214 source "drivers/acpi/Kconfig"
1219 depends on APM || APM_MODULE
1222 tristate "APM (Advanced Power Management) BIOS support"
1223 depends on X86_32 && PM_SLEEP && !X86_VISWS
1225 APM is a BIOS specification for saving power using several different
1226 techniques. This is mostly useful for battery powered laptops with
1227 APM compliant BIOSes. If you say Y here, the system time will be
1228 reset after a RESUME operation, the /proc/apm device will provide
1229 battery status information, and user-space programs will receive
1230 notification of APM "events" (e.g. battery status change).
1232 If you select "Y" here, you can disable actual use of the APM
1233 BIOS by passing the "apm=off" option to the kernel at boot time.
1235 Note that the APM support is almost completely disabled for
1236 machines with more than one CPU.
1238 In order to use APM, you will need supporting software. For location
1239 and more information, read <file:Documentation/pm.txt> and the
1240 Battery Powered Linux mini-HOWTO, available from
1241 <http://www.tldp.org/docs.html#howto>.
1243 This driver does not spin down disk drives (see the hdparm(8)
1244 manpage ("man 8 hdparm") for that), and it doesn't turn off
1245 VESA-compliant "green" monitors.
1247 This driver does not support the TI 4000M TravelMate and the ACER
1248 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1249 desktop machines also don't have compliant BIOSes, and this driver
1250 may cause those machines to panic during the boot phase.
1252 Generally, if you don't have a battery in your machine, there isn't
1253 much point in using this driver and you should say N. If you get
1254 random kernel OOPSes or reboots that don't seem to be related to
1255 anything, try disabling/enabling this option (or disabling/enabling
1258 Some other things you should try when experiencing seemingly random,
1261 1) make sure that you have enough swap space and that it is
1263 2) pass the "no-hlt" option to the kernel
1264 3) switch on floating point emulation in the kernel and pass
1265 the "no387" option to the kernel
1266 4) pass the "floppy=nodma" option to the kernel
1267 5) pass the "mem=4M" option to the kernel (thereby disabling
1268 all but the first 4 MB of RAM)
1269 6) make sure that the CPU is not over clocked.
1270 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1271 8) disable the cache from your BIOS settings
1272 9) install a fan for the video card or exchange video RAM
1273 10) install a better fan for the CPU
1274 11) exchange RAM chips
1275 12) exchange the motherboard.
1277 To compile this driver as a module, choose M here: the
1278 module will be called apm.
1282 config APM_IGNORE_USER_SUSPEND
1283 bool "Ignore USER SUSPEND"
1285 This option will ignore USER SUSPEND requests. On machines with a
1286 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1287 series notebooks, it is necessary to say Y because of a BIOS bug.
1289 config APM_DO_ENABLE
1290 bool "Enable PM at boot time"
1292 Enable APM features at boot time. From page 36 of the APM BIOS
1293 specification: "When disabled, the APM BIOS does not automatically
1294 power manage devices, enter the Standby State, enter the Suspend
1295 State, or take power saving steps in response to CPU Idle calls."
1296 This driver will make CPU Idle calls when Linux is idle (unless this
1297 feature is turned off -- see "Do CPU IDLE calls", below). This
1298 should always save battery power, but more complicated APM features
1299 will be dependent on your BIOS implementation. You may need to turn
1300 this option off if your computer hangs at boot time when using APM
1301 support, or if it beeps continuously instead of suspending. Turn
1302 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1303 T400CDT. This is off by default since most machines do fine without
1307 bool "Make CPU Idle calls when idle"
1309 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1310 On some machines, this can activate improved power savings, such as
1311 a slowed CPU clock rate, when the machine is idle. These idle calls
1312 are made after the idle loop has run for some length of time (e.g.,
1313 333 mS). On some machines, this will cause a hang at boot time or
1314 whenever the CPU becomes idle. (On machines with more than one CPU,
1315 this option does nothing.)
1317 config APM_DISPLAY_BLANK
1318 bool "Enable console blanking using APM"
1320 Enable console blanking using the APM. Some laptops can use this to
1321 turn off the LCD backlight when the screen blanker of the Linux
1322 virtual console blanks the screen. Note that this is only used by
1323 the virtual console screen blanker, and won't turn off the backlight
1324 when using the X Window system. This also doesn't have anything to
1325 do with your VESA-compliant power-saving monitor. Further, this
1326 option doesn't work for all laptops -- it might not turn off your
1327 backlight at all, or it might print a lot of errors to the console,
1328 especially if you are using gpm.
1330 config APM_ALLOW_INTS
1331 bool "Allow interrupts during APM BIOS calls"
1333 Normally we disable external interrupts while we are making calls to
1334 the APM BIOS as a measure to lessen the effects of a badly behaving
1335 BIOS implementation. The BIOS should reenable interrupts if it
1336 needs to. Unfortunately, some BIOSes do not -- especially those in
1337 many of the newer IBM Thinkpads. If you experience hangs when you
1338 suspend, try setting this to Y. Otherwise, say N.
1340 config APM_REAL_MODE_POWER_OFF
1341 bool "Use real mode APM BIOS call to power off"
1343 Use real mode APM BIOS calls to switch off the computer. This is
1344 a work-around for a number of buggy BIOSes. Switch this option on if
1345 your computer crashes instead of powering off properly.
1349 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1351 source "drivers/cpuidle/Kconfig"
1356 menu "Bus options (PCI etc.)"
1359 bool "PCI support" if !X86_VISWS
1360 depends on !X86_VOYAGER
1362 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1364 Find out whether you have a PCI motherboard. PCI is the name of a
1365 bus system, i.e. the way the CPU talks to the other stuff inside
1366 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1367 VESA. If you have PCI, say Y, otherwise N.
1369 The PCI-HOWTO, available from
1370 <http://www.tldp.org/docs.html#howto>, contains valuable
1371 information about which PCI hardware does work under Linux and which
1375 prompt "PCI access mode"
1376 depends on X86_32 && PCI && !X86_VISWS
1379 On PCI systems, the BIOS can be used to detect the PCI devices and
1380 determine their configuration. However, some old PCI motherboards
1381 have BIOS bugs and may crash if this is done. Also, some embedded
1382 PCI-based systems don't have any BIOS at all. Linux can also try to
1383 detect the PCI hardware directly without using the BIOS.
1385 With this option, you can specify how Linux should detect the
1386 PCI devices. If you choose "BIOS", the BIOS will be used,
1387 if you choose "Direct", the BIOS won't be used, and if you
1388 choose "MMConfig", then PCI Express MMCONFIG will be used.
1389 If you choose "Any", the kernel will try MMCONFIG, then the
1390 direct access method and falls back to the BIOS if that doesn't
1391 work. If unsure, go with the default, which is "Any".
1396 config PCI_GOMMCONFIG
1409 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1411 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1414 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1418 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1425 bool "Support mmconfig PCI config space access"
1426 depends on X86_64 && PCI && ACPI
1429 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1430 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1432 DMA remapping (DMAR) devices support enables independent address
1433 translations for Direct Memory Access (DMA) from devices.
1434 These DMA remapping devices are reported via ACPI tables
1435 and include PCI device scope covered by these DMA
1440 prompt "Support for Graphics workaround"
1443 Current Graphics drivers tend to use physical address
1444 for DMA and avoid using DMA APIs. Setting this config
1445 option permits the IOMMU driver to set a unity map for
1446 all the OS-visible memory. Hence the driver can continue
1447 to use physical addresses for DMA.
1449 config DMAR_FLOPPY_WA
1453 Floppy disk drivers are know to bypass DMA API calls
1454 thereby failing to work when IOMMU is enabled. This
1455 workaround will setup a 1:1 mapping for the first
1456 16M to make floppy (an ISA device) work.
1458 source "drivers/pci/pcie/Kconfig"
1460 source "drivers/pci/Kconfig"
1462 # x86_64 have no ISA slots, but do have ISA-style DMA.
1470 depends on !(X86_VOYAGER || X86_VISWS)
1472 Find out whether you have ISA slots on your motherboard. ISA is the
1473 name of a bus system, i.e. the way the CPU talks to the other stuff
1474 inside your box. Other bus systems are PCI, EISA, MicroChannel
1475 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1476 newer boards don't support it. If you have ISA, say Y, otherwise N.
1482 The Extended Industry Standard Architecture (EISA) bus was
1483 developed as an open alternative to the IBM MicroChannel bus.
1485 The EISA bus provided some of the features of the IBM MicroChannel
1486 bus while maintaining backward compatibility with cards made for
1487 the older ISA bus. The EISA bus saw limited use between 1988 and
1488 1995 when it was made obsolete by the PCI bus.
1490 Say Y here if you are building a kernel for an EISA-based machine.
1494 source "drivers/eisa/Kconfig"
1497 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1498 default y if X86_VOYAGER
1500 MicroChannel Architecture is found in some IBM PS/2 machines and
1501 laptops. It is a bus system similar to PCI or ISA. See
1502 <file:Documentation/mca.txt> (and especially the web page given
1503 there) before attempting to build an MCA bus kernel.
1505 source "drivers/mca/Kconfig"
1508 tristate "NatSemi SCx200 support"
1509 depends on !X86_VOYAGER
1511 This provides basic support for National Semiconductor's
1512 (now AMD's) Geode processors. The driver probes for the
1513 PCI-IDs of several on-chip devices, so its a good dependency
1514 for other scx200_* drivers.
1516 If compiled as a module, the driver is named scx200.
1518 config SCx200HR_TIMER
1519 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1520 depends on SCx200 && GENERIC_TIME
1523 This driver provides a clocksource built upon the on-chip
1524 27MHz high-resolution timer. Its also a workaround for
1525 NSC Geode SC-1100's buggy TSC, which loses time when the
1526 processor goes idle (as is done by the scheduler). The
1527 other workaround is idle=poll boot option.
1529 config GEODE_MFGPT_TIMER
1531 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1532 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1534 This driver provides a clock event source based on the MFGPT
1535 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1536 MFGPTs have a better resolution and max interval than the
1537 generic PIT, and are suitable for use as high-res timers.
1543 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1545 source "drivers/pcmcia/Kconfig"
1547 source "drivers/pci/hotplug/Kconfig"
1552 menu "Executable file formats / Emulations"
1554 source "fs/Kconfig.binfmt"
1556 config IA32_EMULATION
1557 bool "IA32 Emulation"
1559 select COMPAT_BINFMT_ELF
1561 Include code to run 32-bit programs under a 64-bit kernel. You should
1562 likely turn this on, unless you're 100% sure that you don't have any
1563 32-bit programs left.
1566 tristate "IA32 a.out support"
1567 depends on IA32_EMULATION
1569 Support old a.out binaries in the 32bit emulation.
1573 depends on IA32_EMULATION
1575 config COMPAT_FOR_U64_ALIGNMENT
1579 config SYSVIPC_COMPAT
1581 depends on X86_64 && COMPAT && SYSVIPC
1586 source "net/Kconfig"
1588 source "drivers/Kconfig"
1590 source "drivers/firmware/Kconfig"
1594 source "kernel/Kconfig.instrumentation"
1596 source "arch/x86/Kconfig.debug"
1598 source "security/Kconfig"
1600 source "crypto/Kconfig"
1602 source "arch/x86/kvm/Kconfig"
1604 source "lib/Kconfig"
projects / linux-2.6 / blob