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
24 depends on SMP && PREEMPT
29 config GENERIC_CMOS_UPDATE
32 config CLOCKSOURCE_WATCHDOG
35 config GENERIC_CLOCKEVENTS
38 config GENERIC_CLOCKEVENTS_BROADCAST
40 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
42 config LOCKDEP_SUPPORT
45 config STACKTRACE_SUPPORT
48 config SEMAPHORE_SLEEPERS
63 config GENERIC_ISA_DMA
73 config GENERIC_HWEIGHT
76 config ARCH_MAY_HAVE_PC_FDC
82 config RWSEM_GENERIC_SPINLOCK
85 config RWSEM_XCHGADD_ALGORITHM
88 config ARCH_HAS_ILOG2_U32
91 config ARCH_HAS_ILOG2_U64
94 config GENERIC_CALIBRATE_DELAY
97 config GENERIC_TIME_VSYSCALL
101 config ARCH_SUPPORTS_OPROFILE
110 config ARCH_POPULATES_NODE_MAP
117 # Use the generic interrupt handling code in kernel/irq/:
118 config GENERIC_HARDIRQS
122 config GENERIC_IRQ_PROBE
126 config GENERIC_PENDING_IRQ
128 depends on GENERIC_HARDIRQS && SMP
133 depends on X86_32 && SMP && !X86_VOYAGER
139 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8)
142 config X86_BIOS_REBOOT
144 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
147 config X86_TRAMPOLINE
149 depends on X86_SMP || (X86_VOYAGER && SMP)
154 source "init/Kconfig"
156 menu "Processor type and features"
158 source "kernel/time/Kconfig"
161 bool "Symmetric multi-processing support"
163 This enables support for systems with more than one CPU. If you have
164 a system with only one CPU, like most personal computers, say N. If
165 you have a system with more than one CPU, say Y.
167 If you say N here, the kernel will run on single and multiprocessor
168 machines, but will use only one CPU of a multiprocessor machine. If
169 you say Y here, the kernel will run on many, but not all,
170 singleprocessor machines. On a singleprocessor machine, the kernel
171 will run faster if you say N here.
173 Note that if you say Y here and choose architecture "586" or
174 "Pentium" under "Processor family", the kernel will not work on 486
175 architectures. Similarly, multiprocessor kernels for the "PPro"
176 architecture may not work on all Pentium based boards.
178 People using multiprocessor machines who say Y here should also say
179 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
180 Management" code will be disabled if you say Y here.
182 See also the <file:Documentation/smp.txt>,
183 <file:Documentation/i386/IO-APIC.txt>,
184 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
185 <http://www.tldp.org/docs.html#howto>.
187 If you don't know what to do here, say N.
190 prompt "Subarchitecture Type"
196 Choose this option if your computer is a standard PC or compatible.
202 Select this for an AMD Elan processor.
204 Do not use this option for K6/Athlon/Opteron processors!
206 If unsure, choose "PC-compatible" instead.
211 select SMP if !BROKEN
213 Voyager is an MCA-based 32-way capable SMP architecture proprietary
214 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
218 If you do not specifically know you have a Voyager based machine,
219 say N here, otherwise the kernel you build will not be bootable.
222 bool "NUMAQ (IBM/Sequent)"
227 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
228 multiquad box. This changes the way that processors are bootstrapped,
229 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
230 You will need a new lynxer.elf file to flash your firmware with - send
231 email to <Martin.Bligh@us.ibm.com>.
234 bool "Summit/EXA (IBM x440)"
235 depends on X86_32 && SMP
237 This option is needed for IBM systems that use the Summit/EXA chipset.
238 In particular, it is needed for the x440.
240 If you don't have one of these computers, you should say N here.
241 If you want to build a NUMA kernel, you must select ACPI.
244 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
245 depends on X86_32 && SMP
247 This option is needed for the systems that have more than 8 CPUs
248 and if the system is not of any sub-arch type above.
250 If you don't have such a system, you should say N here.
253 bool "SGI 320/540 (Visual Workstation)"
256 The SGI Visual Workstation series is an IA32-based workstation
257 based on SGI systems chips with some legacy PC hardware attached.
259 Say Y here to create a kernel to run on the SGI 320 or 540.
261 A kernel compiled for the Visual Workstation will not run on PCs
262 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
264 config X86_GENERICARCH
265 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
268 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
269 It is intended for a generic binary kernel.
270 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
273 bool "Support for Unisys ES7000 IA32 series"
274 depends on X86_32 && SMP
276 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
277 supposed to run on an IA32-based Unisys ES7000 system.
278 Only choose this option if you have such a system, otherwise you
282 bool "Support for ScaleMP vSMP"
283 depends on X86_64 && PCI
285 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
286 supposed to run on these EM64T-based machines. Only choose this option
287 if you have one of these machines.
291 config SCHED_NO_NO_OMIT_FRAME_POINTER
293 prompt "Single-depth WCHAN output"
296 Calculate simpler /proc/<PID>/wchan values. If this option
297 is disabled then wchan values will recurse back to the
298 caller function. This provides more accurate wchan values,
299 at the expense of slightly more scheduling overhead.
301 If in doubt, say "Y".
305 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
307 This changes the kernel so it can modify itself when it is run
308 under a hypervisor, potentially improving performance significantly
309 over full virtualization. However, when run without a hypervisor
310 the kernel is theoretically slower and slightly larger.
312 menuconfig PARAVIRT_GUEST
313 bool "Paravirtualized guest support"
316 Say Y here to get to see options related to running Linux under
317 various hypervisors. This option alone does not add any kernel code.
319 If you say N, all options in this submenu will be skipped and disabled.
323 source "arch/x86/xen/Kconfig"
326 bool "VMI Guest support"
328 depends on !(X86_VISWS || X86_VOYAGER)
330 VMI provides a paravirtualized interface to the VMware ESX server
331 (it could be used by other hypervisors in theory too, but is not
332 at the moment), by linking the kernel to a GPL-ed ROM module
333 provided by the hypervisor.
335 source "arch/x86/lguest/Kconfig"
341 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
344 config HAVE_ARCH_PARSE_SRAT
348 config X86_SUMMIT_NUMA
350 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
352 config X86_CYCLONE_TIMER
354 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
356 config ES7000_CLUSTERED_APIC
358 depends on SMP && X86_ES7000 && MPENTIUMIII
360 source "arch/x86/Kconfig.cpu"
364 prompt "HPET Timer Support" if X86_32
366 Use the IA-PC HPET (High Precision Event Timer) to manage
367 time in preference to the PIT and RTC, if a HPET is
369 HPET is the next generation timer replacing legacy 8254s.
370 The HPET provides a stable time base on SMP
371 systems, unlike the TSC, but it is more expensive to access,
372 as it is off-chip. You can find the HPET spec at
373 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
375 You can safely choose Y here. However, HPET will only be
376 activated if the platform and the BIOS support this feature.
377 Otherwise the 8254 will be used for timing services.
379 Choose N to continue using the legacy 8254 timer.
381 config HPET_EMULATE_RTC
383 depends on HPET_TIMER && RTC=y
385 # Mark as embedded because too many people got it wrong.
386 # The code disables itself when not needed.
388 bool "GART IOMMU support" if EMBEDDED
392 depends on X86_64 && PCI
394 Support for full DMA access of devices with 32bit memory access only
395 on systems with more than 3GB. This is usually needed for USB,
396 sound, many IDE/SATA chipsets and some other devices.
397 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
398 based hardware IOMMU and a software bounce buffer based IOMMU used
399 on Intel systems and as fallback.
400 The code is only active when needed (enough memory and limited
401 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
405 bool "IBM Calgary IOMMU support"
407 depends on X86_64 && PCI && EXPERIMENTAL
409 Support for hardware IOMMUs in IBM's xSeries x366 and x460
410 systems. Needed to run systems with more than 3GB of memory
411 properly with 32-bit PCI devices that do not support DAC
412 (Double Address Cycle). Calgary also supports bus level
413 isolation, where all DMAs pass through the IOMMU. This
414 prevents them from going anywhere except their intended
415 destination. This catches hard-to-find kernel bugs and
416 mis-behaving drivers and devices that do not use the DMA-API
417 properly to set up their DMA buffers. The IOMMU can be
418 turned off at boot time with the iommu=off parameter.
419 Normally the kernel will make the right choice by itself.
422 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
424 prompt "Should Calgary be enabled by default?"
425 depends on CALGARY_IOMMU
427 Should Calgary be enabled by default? if you choose 'y', Calgary
428 will be used (if it exists). If you choose 'n', Calgary will not be
429 used even if it exists. If you choose 'n' and would like to use
430 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
433 # need this always selected by IOMMU for the VIA workaround
437 Support for software bounce buffers used on x86-64 systems
438 which don't have a hardware IOMMU (e.g. the current generation
439 of Intel's x86-64 CPUs). Using this PCI devices which can only
440 access 32-bits of memory can be used on systems with more than
441 3 GB of memory. If unsure, say Y.
445 int "Maximum number of CPUs (2-255)"
448 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
451 This allows you to specify the maximum number of CPUs which this
452 kernel will support. The maximum supported value is 255 and the
453 minimum value which makes sense is 2.
455 This is purely to save memory - each supported CPU adds
456 approximately eight kilobytes to the kernel image.
459 bool "SMT (Hyperthreading) scheduler support"
460 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
462 SMT scheduler support improves the CPU scheduler's decision making
463 when dealing with Intel Pentium 4 chips with HyperThreading at a
464 cost of slightly increased overhead in some places. If unsure say
469 prompt "Multi-core scheduler support"
470 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
472 Multi-core scheduler support improves the CPU scheduler's decision
473 making when dealing with multi-core CPU chips at a cost of slightly
474 increased overhead in some places. If unsure say N here.
476 source "kernel/Kconfig.preempt"
479 bool "Local APIC support on uniprocessors"
480 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
482 A local APIC (Advanced Programmable Interrupt Controller) is an
483 integrated interrupt controller in the CPU. If you have a single-CPU
484 system which has a processor with a local APIC, you can say Y here to
485 enable and use it. If you say Y here even though your machine doesn't
486 have a local APIC, then the kernel will still run with no slowdown at
487 all. The local APIC supports CPU-generated self-interrupts (timer,
488 performance counters), and the NMI watchdog which detects hard
492 bool "IO-APIC support on uniprocessors"
493 depends on X86_UP_APIC
495 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
496 SMP-capable replacement for PC-style interrupt controllers. Most
497 SMP systems and many recent uniprocessor systems have one.
499 If you have a single-CPU system with an IO-APIC, you can say Y here
500 to use it. If you say Y here even though your machine doesn't have
501 an IO-APIC, then the kernel will still run with no slowdown at all.
503 config X86_LOCAL_APIC
505 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
509 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
511 config X86_VISWS_APIC
513 depends on X86_32 && X86_VISWS
516 bool "Machine Check Exception"
517 depends on !X86_VOYAGER
519 Machine Check Exception support allows the processor to notify the
520 kernel if it detects a problem (e.g. overheating, component failure).
521 The action the kernel takes depends on the severity of the problem,
522 ranging from a warning message on the console, to halting the machine.
523 Your processor must be a Pentium or newer to support this - check the
524 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
525 have a design flaw which leads to false MCE events - hence MCE is
526 disabled on all P5 processors, unless explicitly enabled with "mce"
527 as a boot argument. Similarly, if MCE is built in and creates a
528 problem on some new non-standard machine, you can boot with "nomce"
529 to disable it. MCE support simply ignores non-MCE processors like
530 the 386 and 486, so nearly everyone can say Y here.
534 prompt "Intel MCE features"
535 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
537 Additional support for intel specific MCE features such as
542 prompt "AMD MCE features"
543 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
545 Additional support for AMD specific MCE features such as
546 the DRAM Error Threshold.
548 config X86_MCE_NONFATAL
549 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
550 depends on X86_32 && X86_MCE
552 Enabling this feature starts a timer that triggers every 5 seconds which
553 will look at the machine check registers to see if anything happened.
554 Non-fatal problems automatically get corrected (but still logged).
555 Disable this if you don't want to see these messages.
556 Seeing the messages this option prints out may be indicative of dying
557 or out-of-spec (ie, overclocked) hardware.
558 This option only does something on certain CPUs.
559 (AMD Athlon/Duron and Intel Pentium 4)
561 config X86_MCE_P4THERMAL
562 bool "check for P4 thermal throttling interrupt."
563 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
565 Enabling this feature will cause a message to be printed when the P4
566 enters thermal throttling.
569 bool "Enable VM86 support" if EMBEDDED
573 This option is required by programs like DOSEMU to run 16-bit legacy
574 code on X86 processors. It also may be needed by software like
575 XFree86 to initialize some video cards via BIOS. Disabling this
576 option saves about 6k.
579 tristate "Toshiba Laptop support"
582 This adds a driver to safely access the System Management Mode of
583 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
584 not work on models with a Phoenix BIOS. The System Management Mode
585 is used to set the BIOS and power saving options on Toshiba portables.
587 For information on utilities to make use of this driver see the
588 Toshiba Linux utilities web site at:
589 <http://www.buzzard.org.uk/toshiba/>.
591 Say Y if you intend to run this kernel on a Toshiba portable.
595 tristate "Dell laptop support"
598 This adds a driver to safely access the System Management Mode
599 of the CPU on the Dell Inspiron 8000. The System Management Mode
600 is used to read cpu temperature and cooling fan status and to
601 control the fans on the I8K portables.
603 This driver has been tested only on the Inspiron 8000 but it may
604 also work with other Dell laptops. You can force loading on other
605 models by passing the parameter `force=1' to the module. Use at
608 For information on utilities to make use of this driver see the
609 I8K Linux utilities web site at:
610 <http://people.debian.org/~dz/i8k/>
612 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
615 config X86_REBOOTFIXUPS
617 prompt "Enable X86 board specific fixups for reboot"
618 depends on X86_32 && X86
620 This enables chipset and/or board specific fixups to be done
621 in order to get reboot to work correctly. This is only needed on
622 some combinations of hardware and BIOS. The symptom, for which
623 this config is intended, is when reboot ends with a stalled/hung
626 Currently, the only fixup is for the Geode machines using
627 CS5530A and CS5536 chipsets.
629 Say Y if you want to enable the fixup. Currently, it's safe to
630 enable this option even if you don't need it.
634 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
637 If you say Y here, you will be able to update the microcode on
638 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
639 Pentium III, Pentium 4, Xeon etc. You will obviously need the
640 actual microcode binary data itself which is not shipped with the
643 For latest news and information on obtaining all the required
644 ingredients for this driver, check:
645 <http://www.urbanmyth.org/microcode/>.
647 To compile this driver as a module, choose M here: the
648 module will be called microcode.
650 config MICROCODE_OLD_INTERFACE
655 tristate "/dev/cpu/*/msr - Model-specific register support"
657 This device gives privileged processes access to the x86
658 Model-Specific Registers (MSRs). It is a character device with
659 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
660 MSR accesses are directed to a specific CPU on multi-processor
664 tristate "/dev/cpu/*/cpuid - CPU information support"
666 This device gives processes access to the x86 CPUID instruction to
667 be executed on a specific processor. It is a character device
668 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
672 prompt "High Memory Support"
673 default HIGHMEM4G if !X86_NUMAQ
674 default HIGHMEM64G if X86_NUMAQ
679 depends on !X86_NUMAQ
681 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
682 However, the address space of 32-bit x86 processors is only 4
683 Gigabytes large. That means that, if you have a large amount of
684 physical memory, not all of it can be "permanently mapped" by the
685 kernel. The physical memory that's not permanently mapped is called
688 If you are compiling a kernel which will never run on a machine with
689 more than 1 Gigabyte total physical RAM, answer "off" here (default
690 choice and suitable for most users). This will result in a "3GB/1GB"
691 split: 3GB are mapped so that each process sees a 3GB virtual memory
692 space and the remaining part of the 4GB virtual memory space is used
693 by the kernel to permanently map as much physical memory as
696 If the machine has between 1 and 4 Gigabytes physical RAM, then
699 If more than 4 Gigabytes is used then answer "64GB" here. This
700 selection turns Intel PAE (Physical Address Extension) mode on.
701 PAE implements 3-level paging on IA32 processors. PAE is fully
702 supported by Linux, PAE mode is implemented on all recent Intel
703 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
704 then the kernel will not boot on CPUs that don't support PAE!
706 The actual amount of total physical memory will either be
707 auto detected or can be forced by using a kernel command line option
708 such as "mem=256M". (Try "man bootparam" or see the documentation of
709 your boot loader (lilo or loadlin) about how to pass options to the
710 kernel at boot time.)
712 If unsure, say "off".
716 depends on !X86_NUMAQ
718 Select this if you have a 32-bit processor and between 1 and 4
719 gigabytes of physical RAM.
723 depends on !M386 && !M486
726 Select this if you have a 32-bit processor and more than 4
727 gigabytes of physical RAM.
732 depends on EXPERIMENTAL
733 prompt "Memory split" if EMBEDDED
737 Select the desired split between kernel and user memory.
739 If the address range available to the kernel is less than the
740 physical memory installed, the remaining memory will be available
741 as "high memory". Accessing high memory is a little more costly
742 than low memory, as it needs to be mapped into the kernel first.
743 Note that increasing the kernel address space limits the range
744 available to user programs, making the address space there
745 tighter. Selecting anything other than the default 3G/1G split
746 will also likely make your kernel incompatible with binary-only
749 If you are not absolutely sure what you are doing, leave this
753 bool "3G/1G user/kernel split"
754 config VMSPLIT_3G_OPT
756 bool "3G/1G user/kernel split (for full 1G low memory)"
758 bool "2G/2G user/kernel split"
759 config VMSPLIT_2G_OPT
761 bool "2G/2G user/kernel split (for full 2G low memory)"
763 bool "1G/3G user/kernel split"
768 default 0xB0000000 if VMSPLIT_3G_OPT
769 default 0x80000000 if VMSPLIT_2G
770 default 0x78000000 if VMSPLIT_2G_OPT
771 default 0x40000000 if VMSPLIT_1G
777 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
781 prompt "PAE (Physical Address Extension) Support"
782 depends on X86_32 && !HIGHMEM4G
783 select RESOURCES_64BIT
785 PAE is required for NX support, and furthermore enables
786 larger swapspace support for non-overcommit purposes. It
787 has the cost of more pagetable lookup overhead, and also
788 consumes more pagetable space per process.
790 # Common NUMA Features
792 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
794 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
796 default y if (X86_NUMAQ || X86_SUMMIT)
798 Enable NUMA (Non Uniform Memory Access) support.
799 The kernel will try to allocate memory used by a CPU on the
800 local memory controller of the CPU and add some more
801 NUMA awareness to the kernel.
803 For i386 this is currently highly experimental and should be only
804 used for kernel development. It might also cause boot failures.
805 For x86_64 this is recommended on all multiprocessor Opteron systems.
806 If the system is EM64T, you should say N unless your system is
809 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
810 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
814 prompt "Old style AMD Opteron NUMA detection"
815 depends on X86_64 && NUMA && PCI
817 Enable K8 NUMA node topology detection. You should say Y here if
818 you have a multi processor AMD K8 system. This uses an old
819 method to read the NUMA configuration directly from the builtin
820 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
821 instead, which also takes priority if both are compiled in.
823 config X86_64_ACPI_NUMA
825 prompt "ACPI NUMA detection"
826 depends on X86_64 && NUMA && ACPI && PCI
829 Enable ACPI SRAT based node topology detection.
832 bool "NUMA emulation"
833 depends on X86_64 && NUMA
835 Enable NUMA emulation. A flat machine will be split
836 into virtual nodes when booted with "numa=fake=N", where N is the
837 number of nodes. This is only useful for debugging.
841 default "6" if X86_64
842 default "4" if X86_NUMAQ
844 depends on NEED_MULTIPLE_NODES
846 config HAVE_ARCH_BOOTMEM_NODE
848 depends on X86_32 && NUMA
850 config ARCH_HAVE_MEMORY_PRESENT
852 depends on X86_32 && DISCONTIGMEM
854 config NEED_NODE_MEMMAP_SIZE
856 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
858 config HAVE_ARCH_ALLOC_REMAP
860 depends on X86_32 && NUMA
862 config ARCH_FLATMEM_ENABLE
864 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC
866 config ARCH_DISCONTIGMEM_ENABLE
868 depends on NUMA && X86_32
870 config ARCH_DISCONTIGMEM_DEFAULT
872 depends on NUMA && X86_32
874 config ARCH_SPARSEMEM_DEFAULT
878 config ARCH_SPARSEMEM_ENABLE
880 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
881 select SPARSEMEM_STATIC if X86_32
882 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
884 config ARCH_SELECT_MEMORY_MODEL
886 depends on ARCH_SPARSEMEM_ENABLE
888 config ARCH_MEMORY_PROBE
890 depends on MEMORY_HOTPLUG
895 bool "Allocate 3rd-level pagetables from highmem"
896 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
898 The VM uses one page table entry for each page of physical memory.
899 For systems with a lot of RAM, this can be wasteful of precious
900 low memory. Setting this option will put user-space page table
901 entries in high memory.
903 config MATH_EMULATION
905 prompt "Math emulation" if X86_32
907 Linux can emulate a math coprocessor (used for floating point
908 operations) if you don't have one. 486DX and Pentium processors have
909 a math coprocessor built in, 486SX and 386 do not, unless you added
910 a 487DX or 387, respectively. (The messages during boot time can
911 give you some hints here ["man dmesg"].) Everyone needs either a
912 coprocessor or this emulation.
914 If you don't have a math coprocessor, you need to say Y here; if you
915 say Y here even though you have a coprocessor, the coprocessor will
916 be used nevertheless. (This behavior can be changed with the kernel
917 command line option "no387", which comes handy if your coprocessor
918 is broken. Try "man bootparam" or see the documentation of your boot
919 loader (lilo or loadlin) about how to pass options to the kernel at
920 boot time.) This means that it is a good idea to say Y here if you
921 intend to use this kernel on different machines.
923 More information about the internals of the Linux math coprocessor
924 emulation can be found in <file:arch/x86/math-emu/README>.
926 If you are not sure, say Y; apart from resulting in a 66 KB bigger
927 kernel, it won't hurt.
930 bool "MTRR (Memory Type Range Register) support"
932 On Intel P6 family processors (Pentium Pro, Pentium II and later)
933 the Memory Type Range Registers (MTRRs) may be used to control
934 processor access to memory ranges. This is most useful if you have
935 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
936 allows bus write transfers to be combined into a larger transfer
937 before bursting over the PCI/AGP bus. This can increase performance
938 of image write operations 2.5 times or more. Saying Y here creates a
939 /proc/mtrr file which may be used to manipulate your processor's
940 MTRRs. Typically the X server should use this.
942 This code has a reasonably generic interface so that similar
943 control registers on other processors can be easily supported
946 The Cyrix 6x86, 6x86MX and M II processors have Address Range
947 Registers (ARRs) which provide a similar functionality to MTRRs. For
948 these, the ARRs are used to emulate the MTRRs.
949 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
950 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
951 write-combining. All of these processors are supported by this code
952 and it makes sense to say Y here if you have one of them.
954 Saying Y here also fixes a problem with buggy SMP BIOSes which only
955 set the MTRRs for the boot CPU and not for the secondary CPUs. This
956 can lead to all sorts of problems, so it's good to say Y here.
958 You can safely say Y even if your machine doesn't have MTRRs, you'll
959 just add about 9 KB to your kernel.
961 See <file:Documentation/mtrr.txt> for more information.
965 prompt "Boot from EFI support"
968 This enables the kernel to boot on EFI platforms using
969 system configuration information passed to it from the firmware.
970 This also enables the kernel to use any EFI runtime services that are
971 available (such as the EFI variable services).
973 This option is only useful on systems that have EFI firmware
974 and will result in a kernel image that is ~8k larger. In addition,
975 you must use the latest ELILO loader available at
976 <http://elilo.sourceforge.net> in order to take advantage of
977 kernel initialization using EFI information (neither GRUB nor LILO know
978 anything about EFI). However, even with this option, the resultant
979 kernel should continue to boot on existing non-EFI platforms.
983 prompt "Enable kernel irq balancing"
984 depends on X86_32 && SMP && X86_IO_APIC
986 The default yes will allow the kernel to do irq load balancing.
987 Saying no will keep the kernel from doing irq load balancing.
989 # turning this on wastes a bunch of space.
990 # Summit needs it only when NUMA is on
993 depends on X86_32 && (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
997 prompt "Enable seccomp to safely compute untrusted bytecode"
1000 This kernel feature is useful for number crunching applications
1001 that may need to compute untrusted bytecode during their
1002 execution. By using pipes or other transports made available to
1003 the process as file descriptors supporting the read/write
1004 syscalls, it's possible to isolate those applications in
1005 their own address space using seccomp. Once seccomp is
1006 enabled via /proc/<pid>/seccomp, it cannot be disabled
1007 and the task is only allowed to execute a few safe syscalls
1008 defined by each seccomp mode.
1010 If unsure, say Y. Only embedded should say N here.
1012 config CC_STACKPROTECTOR
1013 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1014 depends on X86_64 && EXPERIMENTAL
1016 This option turns on the -fstack-protector GCC feature. This
1017 feature puts, at the beginning of critical functions, a canary
1018 value on the stack just before the return address, and validates
1019 the value just before actually returning. Stack based buffer
1020 overflows (that need to overwrite this return address) now also
1021 overwrite the canary, which gets detected and the attack is then
1022 neutralized via a kernel panic.
1024 This feature requires gcc version 4.2 or above, or a distribution
1025 gcc with the feature backported. Older versions are automatically
1026 detected and for those versions, this configuration option is ignored.
1028 config CC_STACKPROTECTOR_ALL
1029 bool "Use stack-protector for all functions"
1030 depends on CC_STACKPROTECTOR
1032 Normally, GCC only inserts the canary value protection for
1033 functions that use large-ish on-stack buffers. By enabling
1034 this option, GCC will be asked to do this for ALL functions.
1036 source kernel/Kconfig.hz
1039 bool "kexec system call"
1041 kexec is a system call that implements the ability to shutdown your
1042 current kernel, and to start another kernel. It is like a reboot
1043 but it is independent of the system firmware. And like a reboot
1044 you can start any kernel with it, not just Linux.
1046 The name comes from the similarity to the exec system call.
1048 It is an ongoing process to be certain the hardware in a machine
1049 is properly shutdown, so do not be surprised if this code does not
1050 initially work for you. It may help to enable device hotplugging
1051 support. As of this writing the exact hardware interface is
1052 strongly in flux, so no good recommendation can be made.
1055 bool "kernel crash dumps (EXPERIMENTAL)"
1056 depends on EXPERIMENTAL
1057 depends on X86_64 || (X86_32 && HIGHMEM)
1059 Generate crash dump after being started by kexec.
1060 This should be normally only set in special crash dump kernels
1061 which are loaded in the main kernel with kexec-tools into
1062 a specially reserved region and then later executed after
1063 a crash by kdump/kexec. The crash dump kernel must be compiled
1064 to a memory address not used by the main kernel or BIOS using
1065 PHYSICAL_START, or it must be built as a relocatable image
1066 (CONFIG_RELOCATABLE=y).
1067 For more details see Documentation/kdump/kdump.txt
1069 config PHYSICAL_START
1070 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1071 default "0x1000000" if X86_NUMAQ
1072 default "0x200000" if X86_64
1075 This gives the physical address where the kernel is loaded.
1077 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1078 bzImage will decompress itself to above physical address and
1079 run from there. Otherwise, bzImage will run from the address where
1080 it has been loaded by the boot loader and will ignore above physical
1083 In normal kdump cases one does not have to set/change this option
1084 as now bzImage can be compiled as a completely relocatable image
1085 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1086 address. This option is mainly useful for the folks who don't want
1087 to use a bzImage for capturing the crash dump and want to use a
1088 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1089 to be specifically compiled to run from a specific memory area
1090 (normally a reserved region) and this option comes handy.
1092 So if you are using bzImage for capturing the crash dump, leave
1093 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1094 Otherwise if you plan to use vmlinux for capturing the crash dump
1095 change this value to start of the reserved region (Typically 16MB
1096 0x1000000). In other words, it can be set based on the "X" value as
1097 specified in the "crashkernel=YM@XM" command line boot parameter
1098 passed to the panic-ed kernel. Typically this parameter is set as
1099 crashkernel=64M@16M. Please take a look at
1100 Documentation/kdump/kdump.txt for more details about crash dumps.
1102 Usage of bzImage for capturing the crash dump is recommended as
1103 one does not have to build two kernels. Same kernel can be used
1104 as production kernel and capture kernel. Above option should have
1105 gone away after relocatable bzImage support is introduced. But it
1106 is present because there are users out there who continue to use
1107 vmlinux for dump capture. This option should go away down the
1110 Don't change this unless you know what you are doing.
1113 bool "Build a relocatable kernel (EXPERIMENTAL)"
1114 depends on EXPERIMENTAL
1116 This builds a kernel image that retains relocation information
1117 so it can be loaded someplace besides the default 1MB.
1118 The relocations tend to make the kernel binary about 10% larger,
1119 but are discarded at runtime.
1121 One use is for the kexec on panic case where the recovery kernel
1122 must live at a different physical address than the primary
1125 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1126 it has been loaded at and the compile time physical address
1127 (CONFIG_PHYSICAL_START) is ignored.
1129 config PHYSICAL_ALIGN
1131 prompt "Alignment value to which kernel should be aligned" if X86_32
1132 default "0x100000" if X86_32
1133 default "0x200000" if X86_64
1134 range 0x2000 0x400000
1136 This value puts the alignment restrictions on physical address
1137 where kernel is loaded and run from. Kernel is compiled for an
1138 address which meets above alignment restriction.
1140 If bootloader loads the kernel at a non-aligned address and
1141 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1142 address aligned to above value and run from there.
1144 If bootloader loads the kernel at a non-aligned address and
1145 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1146 load address and decompress itself to the address it has been
1147 compiled for and run from there. The address for which kernel is
1148 compiled already meets above alignment restrictions. Hence the
1149 end result is that kernel runs from a physical address meeting
1150 above alignment restrictions.
1152 Don't change this unless you know what you are doing.
1155 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1156 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1158 Say Y here to experiment with turning CPUs off and on, and to
1159 enable suspend on SMP systems. CPUs can be controlled through
1160 /sys/devices/system/cpu.
1161 Say N if you want to disable CPU hotplug and don't need to
1166 prompt "Compat VDSO support"
1167 depends on X86_32 || IA32_EMULATION
1169 Map the 32-bit VDSO to the predictable old-style address too.
1171 Say N here if you are running a sufficiently recent glibc
1172 version (2.3.3 or later), to remove the high-mapped
1173 VDSO mapping and to exclusively use the randomized VDSO.
1179 config ARCH_ENABLE_MEMORY_HOTPLUG
1181 depends on X86_64 || (X86_32 && HIGHMEM)
1183 config HAVE_ARCH_EARLY_PFN_TO_NID
1187 menu "Power management options"
1188 depends on !X86_VOYAGER
1190 config ARCH_HIBERNATION_HEADER
1192 depends on X86_64 && HIBERNATION
1194 source "kernel/power/Kconfig"
1196 source "drivers/acpi/Kconfig"
1199 tristate "APM (Advanced Power Management) BIOS support"
1200 depends on X86_32 && PM_SLEEP && !X86_VISWS
1202 APM is a BIOS specification for saving power using several different
1203 techniques. This is mostly useful for battery powered laptops with
1204 APM compliant BIOSes. If you say Y here, the system time will be
1205 reset after a RESUME operation, the /proc/apm device will provide
1206 battery status information, and user-space programs will receive
1207 notification of APM "events" (e.g. battery status change).
1209 If you select "Y" here, you can disable actual use of the APM
1210 BIOS by passing the "apm=off" option to the kernel at boot time.
1212 Note that the APM support is almost completely disabled for
1213 machines with more than one CPU.
1215 In order to use APM, you will need supporting software. For location
1216 and more information, read <file:Documentation/pm.txt> and the
1217 Battery Powered Linux mini-HOWTO, available from
1218 <http://www.tldp.org/docs.html#howto>.
1220 This driver does not spin down disk drives (see the hdparm(8)
1221 manpage ("man 8 hdparm") for that), and it doesn't turn off
1222 VESA-compliant "green" monitors.
1224 This driver does not support the TI 4000M TravelMate and the ACER
1225 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1226 desktop machines also don't have compliant BIOSes, and this driver
1227 may cause those machines to panic during the boot phase.
1229 Generally, if you don't have a battery in your machine, there isn't
1230 much point in using this driver and you should say N. If you get
1231 random kernel OOPSes or reboots that don't seem to be related to
1232 anything, try disabling/enabling this option (or disabling/enabling
1235 Some other things you should try when experiencing seemingly random,
1238 1) make sure that you have enough swap space and that it is
1240 2) pass the "no-hlt" option to the kernel
1241 3) switch on floating point emulation in the kernel and pass
1242 the "no387" option to the kernel
1243 4) pass the "floppy=nodma" option to the kernel
1244 5) pass the "mem=4M" option to the kernel (thereby disabling
1245 all but the first 4 MB of RAM)
1246 6) make sure that the CPU is not over clocked.
1247 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1248 8) disable the cache from your BIOS settings
1249 9) install a fan for the video card or exchange video RAM
1250 10) install a better fan for the CPU
1251 11) exchange RAM chips
1252 12) exchange the motherboard.
1254 To compile this driver as a module, choose M here: the
1255 module will be called apm.
1259 config APM_IGNORE_USER_SUSPEND
1260 bool "Ignore USER SUSPEND"
1262 This option will ignore USER SUSPEND requests. On machines with a
1263 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1264 series notebooks, it is necessary to say Y because of a BIOS bug.
1266 config APM_DO_ENABLE
1267 bool "Enable PM at boot time"
1269 Enable APM features at boot time. From page 36 of the APM BIOS
1270 specification: "When disabled, the APM BIOS does not automatically
1271 power manage devices, enter the Standby State, enter the Suspend
1272 State, or take power saving steps in response to CPU Idle calls."
1273 This driver will make CPU Idle calls when Linux is idle (unless this
1274 feature is turned off -- see "Do CPU IDLE calls", below). This
1275 should always save battery power, but more complicated APM features
1276 will be dependent on your BIOS implementation. You may need to turn
1277 this option off if your computer hangs at boot time when using APM
1278 support, or if it beeps continuously instead of suspending. Turn
1279 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1280 T400CDT. This is off by default since most machines do fine without
1284 bool "Make CPU Idle calls when idle"
1286 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1287 On some machines, this can activate improved power savings, such as
1288 a slowed CPU clock rate, when the machine is idle. These idle calls
1289 are made after the idle loop has run for some length of time (e.g.,
1290 333 mS). On some machines, this will cause a hang at boot time or
1291 whenever the CPU becomes idle. (On machines with more than one CPU,
1292 this option does nothing.)
1294 config APM_DISPLAY_BLANK
1295 bool "Enable console blanking using APM"
1297 Enable console blanking using the APM. Some laptops can use this to
1298 turn off the LCD backlight when the screen blanker of the Linux
1299 virtual console blanks the screen. Note that this is only used by
1300 the virtual console screen blanker, and won't turn off the backlight
1301 when using the X Window system. This also doesn't have anything to
1302 do with your VESA-compliant power-saving monitor. Further, this
1303 option doesn't work for all laptops -- it might not turn off your
1304 backlight at all, or it might print a lot of errors to the console,
1305 especially if you are using gpm.
1307 config APM_ALLOW_INTS
1308 bool "Allow interrupts during APM BIOS calls"
1310 Normally we disable external interrupts while we are making calls to
1311 the APM BIOS as a measure to lessen the effects of a badly behaving
1312 BIOS implementation. The BIOS should reenable interrupts if it
1313 needs to. Unfortunately, some BIOSes do not -- especially those in
1314 many of the newer IBM Thinkpads. If you experience hangs when you
1315 suspend, try setting this to Y. Otherwise, say N.
1317 config APM_REAL_MODE_POWER_OFF
1318 bool "Use real mode APM BIOS call to power off"
1320 Use real mode APM BIOS calls to switch off the computer. This is
1321 a work-around for a number of buggy BIOSes. Switch this option on if
1322 your computer crashes instead of powering off properly.
1326 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1328 source "drivers/cpuidle/Kconfig"
1333 menu "Bus options (PCI etc.)"
1336 bool "PCI support" if !X86_VISWS
1337 depends on !X86_VOYAGER
1338 default y if X86_VISWS
1339 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1341 Find out whether you have a PCI motherboard. PCI is the name of a
1342 bus system, i.e. the way the CPU talks to the other stuff inside
1343 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1344 VESA. If you have PCI, say Y, otherwise N.
1346 The PCI-HOWTO, available from
1347 <http://www.tldp.org/docs.html#howto>, contains valuable
1348 information about which PCI hardware does work under Linux and which
1352 prompt "PCI access mode"
1353 depends on X86_32 && PCI && !X86_VISWS
1356 On PCI systems, the BIOS can be used to detect the PCI devices and
1357 determine their configuration. However, some old PCI motherboards
1358 have BIOS bugs and may crash if this is done. Also, some embedded
1359 PCI-based systems don't have any BIOS at all. Linux can also try to
1360 detect the PCI hardware directly without using the BIOS.
1362 With this option, you can specify how Linux should detect the
1363 PCI devices. If you choose "BIOS", the BIOS will be used,
1364 if you choose "Direct", the BIOS won't be used, and if you
1365 choose "MMConfig", then PCI Express MMCONFIG will be used.
1366 If you choose "Any", the kernel will try MMCONFIG, then the
1367 direct access method and falls back to the BIOS if that doesn't
1368 work. If unsure, go with the default, which is "Any".
1373 config PCI_GOMMCONFIG
1386 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1388 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1391 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1395 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1402 bool "Support mmconfig PCI config space access"
1403 depends on X86_64 && PCI && ACPI
1406 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1407 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1409 DMA remapping (DMAR) devices support enables independent address
1410 translations for Direct Memory Access (DMA) from devices.
1411 These DMA remapping devices are reported via ACPI tables
1412 and include PCI device scope covered by these DMA
1417 prompt "Support for Graphics workaround"
1420 Current Graphics drivers tend to use physical address
1421 for DMA and avoid using DMA APIs. Setting this config
1422 option permits the IOMMU driver to set a unity map for
1423 all the OS-visible memory. Hence the driver can continue
1424 to use physical addresses for DMA.
1426 config DMAR_FLOPPY_WA
1430 Floppy disk drivers are know to bypass DMA API calls
1431 thereby failing to work when IOMMU is enabled. This
1432 workaround will setup a 1:1 mapping for the first
1433 16M to make floppy (an ISA device) work.
1435 source "drivers/pci/pcie/Kconfig"
1437 source "drivers/pci/Kconfig"
1439 # x86_64 have no ISA slots, but do have ISA-style DMA.
1447 depends on !(X86_VOYAGER || X86_VISWS)
1449 Find out whether you have ISA slots on your motherboard. ISA is the
1450 name of a bus system, i.e. the way the CPU talks to the other stuff
1451 inside your box. Other bus systems are PCI, EISA, MicroChannel
1452 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1453 newer boards don't support it. If you have ISA, say Y, otherwise N.
1459 The Extended Industry Standard Architecture (EISA) bus was
1460 developed as an open alternative to the IBM MicroChannel bus.
1462 The EISA bus provided some of the features of the IBM MicroChannel
1463 bus while maintaining backward compatibility with cards made for
1464 the older ISA bus. The EISA bus saw limited use between 1988 and
1465 1995 when it was made obsolete by the PCI bus.
1467 Say Y here if you are building a kernel for an EISA-based machine.
1471 source "drivers/eisa/Kconfig"
1474 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1475 default y if X86_VOYAGER
1477 MicroChannel Architecture is found in some IBM PS/2 machines and
1478 laptops. It is a bus system similar to PCI or ISA. See
1479 <file:Documentation/mca.txt> (and especially the web page given
1480 there) before attempting to build an MCA bus kernel.
1482 source "drivers/mca/Kconfig"
1485 tristate "NatSemi SCx200 support"
1486 depends on !X86_VOYAGER
1488 This provides basic support for National Semiconductor's
1489 (now AMD's) Geode processors. The driver probes for the
1490 PCI-IDs of several on-chip devices, so its a good dependency
1491 for other scx200_* drivers.
1493 If compiled as a module, the driver is named scx200.
1495 config SCx200HR_TIMER
1496 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1497 depends on SCx200 && GENERIC_TIME
1500 This driver provides a clocksource built upon the on-chip
1501 27MHz high-resolution timer. Its also a workaround for
1502 NSC Geode SC-1100's buggy TSC, which loses time when the
1503 processor goes idle (as is done by the scheduler). The
1504 other workaround is idle=poll boot option.
1506 config GEODE_MFGPT_TIMER
1508 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1509 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1511 This driver provides a clock event source based on the MFGPT
1512 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1513 MFGPTs have a better resolution and max interval than the
1514 generic PIT, and are suitable for use as high-res timers.
1520 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1522 source "drivers/pcmcia/Kconfig"
1524 source "drivers/pci/hotplug/Kconfig"
1529 menu "Executable file formats / Emulations"
1531 source "fs/Kconfig.binfmt"
1533 config IA32_EMULATION
1534 bool "IA32 Emulation"
1537 Include code to run 32-bit programs under a 64-bit kernel. You should
1538 likely turn this on, unless you're 100% sure that you don't have any
1539 32-bit programs left.
1542 tristate "IA32 a.out support"
1543 depends on IA32_EMULATION
1545 Support old a.out binaries in the 32bit emulation.
1549 depends on IA32_EMULATION
1551 config COMPAT_FOR_U64_ALIGNMENT
1555 config SYSVIPC_COMPAT
1557 depends on X86_64 && COMPAT && SYSVIPC
1562 source "net/Kconfig"
1564 source "drivers/Kconfig"
1566 source "drivers/firmware/Kconfig"
1570 source "kernel/Kconfig.instrumentation"
1572 source "arch/x86/Kconfig.debug"
1574 source "security/Kconfig"
1576 source "crypto/Kconfig"
1578 source "lib/Kconfig"
projects / linux-2.6-omap-h63xx.git / blob