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
27 config GENERIC_CMOS_UPDATE
31 config CLOCKSOURCE_WATCHDOG
35 config GENERIC_CLOCKEVENTS
39 config GENERIC_CLOCKEVENTS_BROADCAST
42 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
44 config LOCKDEP_SUPPORT
48 config STACKTRACE_SUPPORT
52 config SEMAPHORE_SLEEPERS
71 config GENERIC_ISA_DMA
84 config GENERIC_HWEIGHT
88 config ARCH_MAY_HAVE_PC_FDC
96 config RWSEM_GENERIC_SPINLOCK
99 config RWSEM_XCHGADD_ALGORITHM
102 config ARCH_HAS_ILOG2_U32
105 config ARCH_HAS_ILOG2_U64
108 config ARCH_HAS_CPU_IDLE_WAIT
111 config GENERIC_CALIBRATE_DELAY
114 config GENERIC_TIME_VSYSCALL
126 config ARCH_POPULATES_NODE_MAP
133 # Use the generic interrupt handling code in kernel/irq/:
134 config GENERIC_HARDIRQS
138 config GENERIC_IRQ_PROBE
142 config GENERIC_PENDING_IRQ
144 depends on GENERIC_HARDIRQS && SMP
149 depends on X86_32 && SMP && !X86_VOYAGER
154 depends on SMP && !(X86_VISWS || X86_VOYAGER || MK8)
157 config X86_BIOS_REBOOT
159 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
162 config X86_TRAMPOLINE
164 depends on X86_SMP || (X86_VOYAGER && SMP)
169 source "init/Kconfig"
171 menu "Processor type and features"
173 source "kernel/time/Kconfig"
176 bool "Symmetric multi-processing support"
178 This enables support for systems with more than one CPU. If you have
179 a system with only one CPU, like most personal computers, say N. If
180 you have a system with more than one CPU, say Y.
182 If you say N here, the kernel will run on single and multiprocessor
183 machines, but will use only one CPU of a multiprocessor machine. If
184 you say Y here, the kernel will run on many, but not all,
185 singleprocessor machines. On a singleprocessor machine, the kernel
186 will run faster if you say N here.
188 Note that if you say Y here and choose architecture "586" or
189 "Pentium" under "Processor family", the kernel will not work on 486
190 architectures. Similarly, multiprocessor kernels for the "PPro"
191 architecture may not work on all Pentium based boards.
193 People using multiprocessor machines who say Y here should also say
194 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
195 Management" code will be disabled if you say Y here.
197 See also the <file:Documentation/smp.txt>,
198 <file:Documentation/i386/IO-APIC.txt>,
199 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
200 <http://www.tldp.org/docs.html#howto>.
202 If you don't know what to do here, say N.
205 prompt "Subarchitecture Type"
211 Choose this option if your computer is a standard PC or compatible.
217 Select this for an AMD Elan processor.
219 Do not use this option for K6/Athlon/Opteron processors!
221 If unsure, choose "PC-compatible" instead.
226 select SMP if !BROKEN
228 Voyager is an MCA-based 32-way capable SMP architecture proprietary
229 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
233 If you do not specifically know you have a Voyager based machine,
234 say N here, otherwise the kernel you build will not be bootable.
237 bool "NUMAQ (IBM/Sequent)"
242 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
243 multiquad box. This changes the way that processors are bootstrapped,
244 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
245 You will need a new lynxer.elf file to flash your firmware with - send
246 email to <Martin.Bligh@us.ibm.com>.
249 bool "Summit/EXA (IBM x440)"
250 depends on X86_32 && SMP
252 This option is needed for IBM systems that use the Summit/EXA chipset.
253 In particular, it is needed for the x440.
255 If you don't have one of these computers, you should say N here.
256 If you want to build a NUMA kernel, you must select ACPI.
259 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
260 depends on X86_32 && SMP
262 This option is needed for the systems that have more than 8 CPUs
263 and if the system is not of any sub-arch type above.
265 If you don't have such a system, you should say N here.
268 bool "SGI 320/540 (Visual Workstation)"
271 The SGI Visual Workstation series is an IA32-based workstation
272 based on SGI systems chips with some legacy PC hardware attached.
274 Say Y here to create a kernel to run on the SGI 320 or 540.
276 A kernel compiled for the Visual Workstation will not run on PCs
277 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
279 config X86_GENERICARCH
280 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
283 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
284 It is intended for a generic binary kernel.
285 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
288 bool "Support for Unisys ES7000 IA32 series"
289 depends on X86_32 && SMP
291 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
292 supposed to run on an IA32-based Unisys ES7000 system.
293 Only choose this option if you have such a system, otherwise you
297 bool "Support for ScaleMP vSMP"
298 depends on X86_64 && PCI
300 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
301 supposed to run on these EM64T-based machines. Only choose this option
302 if you have one of these machines.
306 config SCHED_NO_NO_OMIT_FRAME_POINTER
307 bool "Single-depth WCHAN output"
311 Calculate simpler /proc/<PID>/wchan values. If this option
312 is disabled then wchan values will recurse back to the
313 caller function. This provides more accurate wchan values,
314 at the expense of slightly more scheduling overhead.
316 If in doubt, say "Y".
320 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
322 This changes the kernel so it can modify itself when it is run
323 under a hypervisor, potentially improving performance significantly
324 over full virtualization. However, when run without a hypervisor
325 the kernel is theoretically slower and slightly larger.
327 menuconfig PARAVIRT_GUEST
328 bool "Paravirtualized guest support"
331 Say Y here to get to see options related to running Linux under
332 various hypervisors. This option alone does not add any kernel code.
334 If you say N, all options in this submenu will be skipped and disabled.
338 source "arch/x86/xen/Kconfig"
341 bool "VMI Guest support"
343 depends on !(X86_VISWS || X86_VOYAGER)
345 VMI provides a paravirtualized interface to the VMware ESX server
346 (it could be used by other hypervisors in theory too, but is not
347 at the moment), by linking the kernel to a GPL-ed ROM module
348 provided by the hypervisor.
350 source "arch/x86/lguest/Kconfig"
357 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
360 config HAVE_ARCH_PARSE_SRAT
365 config X86_SUMMIT_NUMA
368 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
370 config X86_CYCLONE_TIMER
373 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
375 config ES7000_CLUSTERED_APIC
378 depends on SMP && X86_ES7000 && MPENTIUMIII
380 source "arch/x86/Kconfig.cpu"
384 prompt "HPET Timer Support" if X86_32
387 Use the IA-PC HPET (High Precision Event Timer) to manage
388 time in preference to the PIT and RTC, if a HPET is
390 HPET is the next generation timer replacing legacy 8254s.
391 The HPET provides a stable time base on SMP
392 systems, unlike the TSC, but it is more expensive to access,
393 as it is off-chip. You can find the HPET spec at
394 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
396 You can safely choose Y here. However, HPET will only be
397 activated if the platform and the BIOS support this feature.
398 Otherwise the 8254 will be used for timing services.
400 Choose N to continue using the legacy 8254 timer.
402 config HPET_EMULATE_RTC
404 depends on HPET_TIMER && RTC=y
407 # Mark as embedded because too many people got it wrong.
408 # The code disables itself when not needed.
410 bool "GART IOMMU support" if EMBEDDED
414 depends on X86_64 && PCI
416 Support for full DMA access of devices with 32bit memory access only
417 on systems with more than 3GB. This is usually needed for USB,
418 sound, many IDE/SATA chipsets and some other devices.
419 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
420 based hardware IOMMU and a software bounce buffer based IOMMU used
421 on Intel systems and as fallback.
422 The code is only active when needed (enough memory and limited
423 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
427 bool "IBM Calgary IOMMU support"
429 depends on X86_64 && PCI && EXPERIMENTAL
431 Support for hardware IOMMUs in IBM's xSeries x366 and x460
432 systems. Needed to run systems with more than 3GB of memory
433 properly with 32-bit PCI devices that do not support DAC
434 (Double Address Cycle). Calgary also supports bus level
435 isolation, where all DMAs pass through the IOMMU. This
436 prevents them from going anywhere except their intended
437 destination. This catches hard-to-find kernel bugs and
438 mis-behaving drivers and devices that do not use the DMA-API
439 properly to set up their DMA buffers. The IOMMU can be
440 turned off at boot time with the iommu=off parameter.
441 Normally the kernel will make the right choice by itself.
444 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
445 bool "Should Calgary be enabled by default?"
447 depends on CALGARY_IOMMU
449 Should Calgary be enabled by default? if you choose 'y', Calgary
450 will be used (if it exists). If you choose 'n', Calgary will not be
451 used even if it exists. If you choose 'n' and would like to use
452 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
455 # need this always selected by IOMMU for the VIA workaround
459 Support for software bounce buffers used on x86-64 systems
460 which don't have a hardware IOMMU (e.g. the current generation
461 of Intel's x86-64 CPUs). Using this PCI devices which can only
462 access 32-bits of memory can be used on systems with more than
463 3 GB of memory. If unsure, say Y.
467 int "Maximum number of CPUs (2-255)"
470 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
473 This allows you to specify the maximum number of CPUs which this
474 kernel will support. The maximum supported value is 255 and the
475 minimum value which makes sense is 2.
477 This is purely to save memory - each supported CPU adds
478 approximately eight kilobytes to the kernel image.
481 bool "SMT (Hyperthreading) scheduler support"
482 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
484 SMT scheduler support improves the CPU scheduler's decision making
485 when dealing with Intel Pentium 4 chips with HyperThreading at a
486 cost of slightly increased overhead in some places. If unsure say
490 bool "Multi-core scheduler support"
491 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
494 Multi-core scheduler support improves the CPU scheduler's decision
495 making when dealing with multi-core CPU chips at a cost of slightly
496 increased overhead in some places. If unsure say N here.
498 source "kernel/Kconfig.preempt"
501 bool "Local APIC support on uniprocessors"
502 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
504 A local APIC (Advanced Programmable Interrupt Controller) is an
505 integrated interrupt controller in the CPU. If you have a single-CPU
506 system which has a processor with a local APIC, you can say Y here to
507 enable and use it. If you say Y here even though your machine doesn't
508 have a local APIC, then the kernel will still run with no slowdown at
509 all. The local APIC supports CPU-generated self-interrupts (timer,
510 performance counters), and the NMI watchdog which detects hard
514 bool "IO-APIC support on uniprocessors"
515 depends on X86_UP_APIC
517 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
518 SMP-capable replacement for PC-style interrupt controllers. Most
519 SMP systems and many recent uniprocessor systems have one.
521 If you have a single-CPU system with an IO-APIC, you can say Y here
522 to use it. If you say Y here even though your machine doesn't have
523 an IO-APIC, then the kernel will still run with no slowdown at all.
525 config X86_LOCAL_APIC
527 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
532 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
535 config X86_VISWS_APIC
537 depends on X86_32 && X86_VISWS
541 bool "Machine Check Exception"
542 depends on !X86_VOYAGER
544 Machine Check Exception support allows the processor to notify the
545 kernel if it detects a problem (e.g. overheating, component failure).
546 The action the kernel takes depends on the severity of the problem,
547 ranging from a warning message on the console, to halting the machine.
548 Your processor must be a Pentium or newer to support this - check the
549 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
550 have a design flaw which leads to false MCE events - hence MCE is
551 disabled on all P5 processors, unless explicitly enabled with "mce"
552 as a boot argument. Similarly, if MCE is built in and creates a
553 problem on some new non-standard machine, you can boot with "nomce"
554 to disable it. MCE support simply ignores non-MCE processors like
555 the 386 and 486, so nearly everyone can say Y here.
558 bool "Intel MCE features"
559 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
562 Additional support for intel specific MCE features such as
566 bool "AMD MCE features"
567 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
570 Additional support for AMD specific MCE features such as
571 the DRAM Error Threshold.
573 config X86_MCE_NONFATAL
574 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
575 depends on X86_32 && X86_MCE
577 Enabling this feature starts a timer that triggers every 5 seconds which
578 will look at the machine check registers to see if anything happened.
579 Non-fatal problems automatically get corrected (but still logged).
580 Disable this if you don't want to see these messages.
581 Seeing the messages this option prints out may be indicative of dying
582 or out-of-spec (ie, overclocked) hardware.
583 This option only does something on certain CPUs.
584 (AMD Athlon/Duron and Intel Pentium 4)
586 config X86_MCE_P4THERMAL
587 bool "check for P4 thermal throttling interrupt."
588 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
590 Enabling this feature will cause a message to be printed when the P4
591 enters thermal throttling.
594 bool "Enable VM86 support" if EMBEDDED
598 This option is required by programs like DOSEMU to run 16-bit legacy
599 code on X86 processors. It also may be needed by software like
600 XFree86 to initialize some video cards via BIOS. Disabling this
601 option saves about 6k.
604 tristate "Toshiba Laptop support"
607 This adds a driver to safely access the System Management Mode of
608 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
609 not work on models with a Phoenix BIOS. The System Management Mode
610 is used to set the BIOS and power saving options on Toshiba portables.
612 For information on utilities to make use of this driver see the
613 Toshiba Linux utilities web site at:
614 <http://www.buzzard.org.uk/toshiba/>.
616 Say Y if you intend to run this kernel on a Toshiba portable.
620 tristate "Dell laptop support"
623 This adds a driver to safely access the System Management Mode
624 of the CPU on the Dell Inspiron 8000. The System Management Mode
625 is used to read cpu temperature and cooling fan status and to
626 control the fans on the I8K portables.
628 This driver has been tested only on the Inspiron 8000 but it may
629 also work with other Dell laptops. You can force loading on other
630 models by passing the parameter `force=1' to the module. Use at
633 For information on utilities to make use of this driver see the
634 I8K Linux utilities web site at:
635 <http://people.debian.org/~dz/i8k/>
637 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
640 config X86_REBOOTFIXUPS
641 bool "Enable X86 board specific fixups for reboot"
642 depends on X86_32 && X86
645 This enables chipset and/or board specific fixups to be done
646 in order to get reboot to work correctly. This is only needed on
647 some combinations of hardware and BIOS. The symptom, for which
648 this config is intended, is when reboot ends with a stalled/hung
651 Currently, the only fixup is for the Geode machines using
652 CS5530A and CS5536 chipsets.
654 Say Y if you want to enable the fixup. Currently, it's safe to
655 enable this option even if you don't need it.
659 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
662 If you say Y here, you will be able to update the microcode on
663 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
664 Pentium III, Pentium 4, Xeon etc. You will obviously need the
665 actual microcode binary data itself which is not shipped with the
668 For latest news and information on obtaining all the required
669 ingredients for this driver, check:
670 <http://www.urbanmyth.org/microcode/>.
672 To compile this driver as a module, choose M here: the
673 module will be called microcode.
675 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 bool "PAE (Physical Address Extension) Support"
809 depends on X86_32 && !HIGHMEM4G
810 select RESOURCES_64BIT
812 PAE is required for NX support, and furthermore enables
813 larger swapspace support for non-overcommit purposes. It
814 has the cost of more pagetable lookup overhead, and also
815 consumes more pagetable space per process.
817 # Common NUMA Features
819 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
821 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
823 default y if (X86_NUMAQ || X86_SUMMIT)
825 Enable NUMA (Non Uniform Memory Access) support.
826 The kernel will try to allocate memory used by a CPU on the
827 local memory controller of the CPU and add some more
828 NUMA awareness to the kernel.
830 For i386 this is currently highly experimental and should be only
831 used for kernel development. It might also cause boot failures.
832 For x86_64 this is recommended on all multiprocessor Opteron systems.
833 If the system is EM64T, you should say N unless your system is
836 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
837 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
840 bool "Old style AMD Opteron NUMA detection"
841 depends on X86_64 && NUMA && PCI
844 Enable K8 NUMA node topology detection. You should say Y here if
845 you have a multi processor AMD K8 system. This uses an old
846 method to read the NUMA configuration directly from the builtin
847 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
848 instead, which also takes priority if both are compiled in.
850 config X86_64_ACPI_NUMA
851 bool "ACPI NUMA detection"
852 depends on X86_64 && NUMA && ACPI && PCI
856 Enable ACPI SRAT based node topology detection.
859 bool "NUMA emulation"
860 depends on X86_64 && NUMA
862 Enable NUMA emulation. A flat machine will be split
863 into virtual nodes when booted with "numa=fake=N", where N is the
864 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
878 config ARCH_HAVE_MEMORY_PRESENT
880 depends on X86_32 && DISCONTIGMEM
883 config NEED_NODE_MEMMAP_SIZE
885 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
888 config HAVE_ARCH_ALLOC_REMAP
890 depends on X86_32 && NUMA
893 config ARCH_FLATMEM_ENABLE
895 depends on (X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC) || (X86_64 && !NUMA)
897 config ARCH_DISCONTIGMEM_ENABLE
901 config ARCH_DISCONTIGMEM_DEFAULT
905 config ARCH_SPARSEMEM_ENABLE
907 depends on NUMA || (EXPERIMENTAL && (X86_PC || X86_64))
908 select SPARSEMEM_STATIC if X86_32
909 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
911 config ARCH_SELECT_MEMORY_MODEL
913 depends on X86_32 && 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.
991 bool "Boot from EFI support"
992 depends on X86_32 && ACPI
995 This enables the kernel to boot on EFI platforms using
996 system configuration information passed to it from the firmware.
997 This also enables the kernel to use any EFI runtime services that are
998 available (such as the EFI variable services).
1000 This option is only useful on systems that have EFI firmware
1001 and will result in a kernel image that is ~8k larger. In addition,
1002 you must use the latest ELILO loader available at
1003 <http://elilo.sourceforge.net> in order to take advantage of
1004 kernel initialization using EFI information (neither GRUB nor LILO know
1005 anything about EFI). However, even with this option, the resultant
1006 kernel should continue to boot on existing non-EFI platforms.
1009 bool "Enable kernel irq balancing"
1010 depends on X86_32 && SMP && X86_IO_APIC
1013 The default yes will allow the kernel to do irq load balancing.
1014 Saying no will keep the kernel from doing irq load balancing.
1016 # turning this on wastes a bunch of space.
1017 # Summit needs it only when NUMA is on
1020 depends on X86_32 && (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
1024 bool "Enable seccomp to safely compute untrusted bytecode"
1028 This kernel feature is useful for number crunching applications
1029 that may need to compute untrusted bytecode during their
1030 execution. By using pipes or other transports made available to
1031 the process as file descriptors supporting the read/write
1032 syscalls, it's possible to isolate those applications in
1033 their own address space using seccomp. Once seccomp is
1034 enabled via /proc/<pid>/seccomp, it cannot be disabled
1035 and the task is only allowed to execute a few safe syscalls
1036 defined by each seccomp mode.
1038 If unsure, say Y. Only embedded should say N here.
1040 config CC_STACKPROTECTOR
1041 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1042 depends on X86_64 && EXPERIMENTAL
1044 This option turns on the -fstack-protector GCC feature. This
1045 feature puts, at the beginning of critical functions, a canary
1046 value on the stack just before the return address, and validates
1047 the value just before actually returning. Stack based buffer
1048 overflows (that need to overwrite this return address) now also
1049 overwrite the canary, which gets detected and the attack is then
1050 neutralized via a kernel panic.
1052 This feature requires gcc version 4.2 or above, or a distribution
1053 gcc with the feature backported. Older versions are automatically
1054 detected and for those versions, this configuration option is ignored.
1056 config CC_STACKPROTECTOR_ALL
1057 bool "Use stack-protector for all functions"
1058 depends on CC_STACKPROTECTOR
1060 Normally, GCC only inserts the canary value protection for
1061 functions that use large-ish on-stack buffers. By enabling
1062 this option, GCC will be asked to do this for ALL functions.
1064 source kernel/Kconfig.hz
1067 bool "kexec system call"
1069 kexec is a system call that implements the ability to shutdown your
1070 current kernel, and to start another kernel. It is like a reboot
1071 but it is independent of the system firmware. And like a reboot
1072 you can start any kernel with it, not just Linux.
1074 The name comes from the similarity to the exec system call.
1076 It is an ongoing process to be certain the hardware in a machine
1077 is properly shutdown, so do not be surprised if this code does not
1078 initially work for you. It may help to enable device hotplugging
1079 support. As of this writing the exact hardware interface is
1080 strongly in flux, so no good recommendation can be made.
1083 bool "kernel crash dumps (EXPERIMENTAL)"
1084 depends on EXPERIMENTAL
1085 depends on X86_64 || (X86_32 && HIGHMEM)
1087 Generate crash dump after being started by kexec.
1088 This should be normally only set in special crash dump kernels
1089 which are loaded in the main kernel with kexec-tools into
1090 a specially reserved region and then later executed after
1091 a crash by kdump/kexec. The crash dump kernel must be compiled
1092 to a memory address not used by the main kernel or BIOS using
1093 PHYSICAL_START, or it must be built as a relocatable image
1094 (CONFIG_RELOCATABLE=y).
1095 For more details see Documentation/kdump/kdump.txt
1097 config PHYSICAL_START
1098 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1099 default "0x1000000" if X86_NUMAQ
1100 default "0x200000" if X86_64
1103 This gives the physical address where the kernel is loaded.
1105 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1106 bzImage will decompress itself to above physical address and
1107 run from there. Otherwise, bzImage will run from the address where
1108 it has been loaded by the boot loader and will ignore above physical
1111 In normal kdump cases one does not have to set/change this option
1112 as now bzImage can be compiled as a completely relocatable image
1113 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1114 address. This option is mainly useful for the folks who don't want
1115 to use a bzImage for capturing the crash dump and want to use a
1116 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1117 to be specifically compiled to run from a specific memory area
1118 (normally a reserved region) and this option comes handy.
1120 So if you are using bzImage for capturing the crash dump, leave
1121 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1122 Otherwise if you plan to use vmlinux for capturing the crash dump
1123 change this value to start of the reserved region (Typically 16MB
1124 0x1000000). In other words, it can be set based on the "X" value as
1125 specified in the "crashkernel=YM@XM" command line boot parameter
1126 passed to the panic-ed kernel. Typically this parameter is set as
1127 crashkernel=64M@16M. Please take a look at
1128 Documentation/kdump/kdump.txt for more details about crash dumps.
1130 Usage of bzImage for capturing the crash dump is recommended as
1131 one does not have to build two kernels. Same kernel can be used
1132 as production kernel and capture kernel. Above option should have
1133 gone away after relocatable bzImage support is introduced. But it
1134 is present because there are users out there who continue to use
1135 vmlinux for dump capture. This option should go away down the
1138 Don't change this unless you know what you are doing.
1141 bool "Build a relocatable kernel (EXPERIMENTAL)"
1142 depends on EXPERIMENTAL
1144 This builds a kernel image that retains relocation information
1145 so it can be loaded someplace besides the default 1MB.
1146 The relocations tend to make the kernel binary about 10% larger,
1147 but are discarded at runtime.
1149 One use is for the kexec on panic case where the recovery kernel
1150 must live at a different physical address than the primary
1153 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1154 it has been loaded at and the compile time physical address
1155 (CONFIG_PHYSICAL_START) is ignored.
1157 config PHYSICAL_ALIGN
1159 prompt "Alignment value to which kernel should be aligned" if X86_32
1160 default "0x100000" if X86_32
1161 default "0x200000" if X86_64
1162 range 0x2000 0x400000
1164 This value puts the alignment restrictions on physical address
1165 where kernel is loaded and run from. Kernel is compiled for an
1166 address which meets above alignment restriction.
1168 If bootloader loads the kernel at a non-aligned address and
1169 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1170 address aligned to above value and run from there.
1172 If bootloader loads the kernel at a non-aligned address and
1173 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1174 load address and decompress itself to the address it has been
1175 compiled for and run from there. The address for which kernel is
1176 compiled already meets above alignment restrictions. Hence the
1177 end result is that kernel runs from a physical address meeting
1178 above alignment restrictions.
1180 Don't change this unless you know what you are doing.
1183 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1184 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1186 Say Y here to experiment with turning CPUs off and on, and to
1187 enable suspend on SMP systems. CPUs can be controlled through
1188 /sys/devices/system/cpu.
1189 Say N if you want to disable CPU hotplug and don't need to
1193 bool "Compat VDSO support"
1197 Map the VDSO to the predictable old-style address too.
1199 Say N here if you are running a sufficiently recent glibc
1200 version (2.3.3 or later), to remove the high-mapped
1201 VDSO mapping and to exclusively use the randomized VDSO.
1207 config ARCH_ENABLE_MEMORY_HOTPLUG
1209 depends on X86_64 || (X86_32 && HIGHMEM)
1211 config MEMORY_HOTPLUG_RESERVE
1213 depends on (MEMORY_HOTPLUG && DISCONTIGMEM)
1215 config HAVE_ARCH_EARLY_PFN_TO_NID
1219 config OUT_OF_LINE_PFN_TO_PAGE
1221 depends on DISCONTIGMEM
1223 menu "Power management options"
1224 depends on !X86_VOYAGER
1226 config ARCH_HIBERNATION_HEADER
1228 depends on X86_64 && HIBERNATION
1231 source "kernel/power/Kconfig"
1233 source "drivers/acpi/Kconfig"
1236 tristate "APM (Advanced Power Management) BIOS support"
1237 depends on X86_32 && PM_SLEEP && !X86_VISWS
1239 APM is a BIOS specification for saving power using several different
1240 techniques. This is mostly useful for battery powered laptops with
1241 APM compliant BIOSes. If you say Y here, the system time will be
1242 reset after a RESUME operation, the /proc/apm device will provide
1243 battery status information, and user-space programs will receive
1244 notification of APM "events" (e.g. battery status change).
1246 If you select "Y" here, you can disable actual use of the APM
1247 BIOS by passing the "apm=off" option to the kernel at boot time.
1249 Note that the APM support is almost completely disabled for
1250 machines with more than one CPU.
1252 In order to use APM, you will need supporting software. For location
1253 and more information, read <file:Documentation/pm.txt> and the
1254 Battery Powered Linux mini-HOWTO, available from
1255 <http://www.tldp.org/docs.html#howto>.
1257 This driver does not spin down disk drives (see the hdparm(8)
1258 manpage ("man 8 hdparm") for that), and it doesn't turn off
1259 VESA-compliant "green" monitors.
1261 This driver does not support the TI 4000M TravelMate and the ACER
1262 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1263 desktop machines also don't have compliant BIOSes, and this driver
1264 may cause those machines to panic during the boot phase.
1266 Generally, if you don't have a battery in your machine, there isn't
1267 much point in using this driver and you should say N. If you get
1268 random kernel OOPSes or reboots that don't seem to be related to
1269 anything, try disabling/enabling this option (or disabling/enabling
1272 Some other things you should try when experiencing seemingly random,
1275 1) make sure that you have enough swap space and that it is
1277 2) pass the "no-hlt" option to the kernel
1278 3) switch on floating point emulation in the kernel and pass
1279 the "no387" option to the kernel
1280 4) pass the "floppy=nodma" option to the kernel
1281 5) pass the "mem=4M" option to the kernel (thereby disabling
1282 all but the first 4 MB of RAM)
1283 6) make sure that the CPU is not over clocked.
1284 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1285 8) disable the cache from your BIOS settings
1286 9) install a fan for the video card or exchange video RAM
1287 10) install a better fan for the CPU
1288 11) exchange RAM chips
1289 12) exchange the motherboard.
1291 To compile this driver as a module, choose M here: the
1292 module will be called apm.
1296 config APM_IGNORE_USER_SUSPEND
1297 bool "Ignore USER SUSPEND"
1299 This option will ignore USER SUSPEND requests. On machines with a
1300 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1301 series notebooks, it is necessary to say Y because of a BIOS bug.
1303 config APM_DO_ENABLE
1304 bool "Enable PM at boot time"
1306 Enable APM features at boot time. From page 36 of the APM BIOS
1307 specification: "When disabled, the APM BIOS does not automatically
1308 power manage devices, enter the Standby State, enter the Suspend
1309 State, or take power saving steps in response to CPU Idle calls."
1310 This driver will make CPU Idle calls when Linux is idle (unless this
1311 feature is turned off -- see "Do CPU IDLE calls", below). This
1312 should always save battery power, but more complicated APM features
1313 will be dependent on your BIOS implementation. You may need to turn
1314 this option off if your computer hangs at boot time when using APM
1315 support, or if it beeps continuously instead of suspending. Turn
1316 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1317 T400CDT. This is off by default since most machines do fine without
1321 bool "Make CPU Idle calls when idle"
1323 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1324 On some machines, this can activate improved power savings, such as
1325 a slowed CPU clock rate, when the machine is idle. These idle calls
1326 are made after the idle loop has run for some length of time (e.g.,
1327 333 mS). On some machines, this will cause a hang at boot time or
1328 whenever the CPU becomes idle. (On machines with more than one CPU,
1329 this option does nothing.)
1331 config APM_DISPLAY_BLANK
1332 bool "Enable console blanking using APM"
1334 Enable console blanking using the APM. Some laptops can use this to
1335 turn off the LCD backlight when the screen blanker of the Linux
1336 virtual console blanks the screen. Note that this is only used by
1337 the virtual console screen blanker, and won't turn off the backlight
1338 when using the X Window system. This also doesn't have anything to
1339 do with your VESA-compliant power-saving monitor. Further, this
1340 option doesn't work for all laptops -- it might not turn off your
1341 backlight at all, or it might print a lot of errors to the console,
1342 especially if you are using gpm.
1344 config APM_ALLOW_INTS
1345 bool "Allow interrupts during APM BIOS calls"
1347 Normally we disable external interrupts while we are making calls to
1348 the APM BIOS as a measure to lessen the effects of a badly behaving
1349 BIOS implementation. The BIOS should reenable interrupts if it
1350 needs to. Unfortunately, some BIOSes do not -- especially those in
1351 many of the newer IBM Thinkpads. If you experience hangs when you
1352 suspend, try setting this to Y. Otherwise, say N.
1354 config APM_REAL_MODE_POWER_OFF
1355 bool "Use real mode APM BIOS call to power off"
1357 Use real mode APM BIOS calls to switch off the computer. This is
1358 a work-around for a number of buggy BIOSes. Switch this option on if
1359 your computer crashes instead of powering off properly.
1363 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1365 source "drivers/cpuidle/Kconfig"
1370 menu "Bus options (PCI etc.)"
1373 bool "PCI support" if !X86_VISWS
1374 depends on !X86_VOYAGER
1375 default y if X86_VISWS
1376 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1378 Find out whether you have a PCI motherboard. PCI is the name of a
1379 bus system, i.e. the way the CPU talks to the other stuff inside
1380 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1381 VESA. If you have PCI, say Y, otherwise N.
1383 The PCI-HOWTO, available from
1384 <http://www.tldp.org/docs.html#howto>, contains valuable
1385 information about which PCI hardware does work under Linux and which
1389 prompt "PCI access mode"
1390 depends on X86_32 && PCI && !X86_VISWS
1393 On PCI systems, the BIOS can be used to detect the PCI devices and
1394 determine their configuration. However, some old PCI motherboards
1395 have BIOS bugs and may crash if this is done. Also, some embedded
1396 PCI-based systems don't have any BIOS at all. Linux can also try to
1397 detect the PCI hardware directly without using the BIOS.
1399 With this option, you can specify how Linux should detect the
1400 PCI devices. If you choose "BIOS", the BIOS will be used,
1401 if you choose "Direct", the BIOS won't be used, and if you
1402 choose "MMConfig", then PCI Express MMCONFIG will be used.
1403 If you choose "Any", the kernel will try MMCONFIG, then the
1404 direct access method and falls back to the BIOS if that doesn't
1405 work. If unsure, go with the default, which is "Any".
1410 config PCI_GOMMCONFIG
1423 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1426 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1429 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1434 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1443 bool "Support mmconfig PCI config space access"
1444 depends on X86_64 && PCI && ACPI
1447 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1448 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1450 DMA remapping (DMAR) devices support enables independent address
1451 translations for Direct Memory Access (DMA) from devices.
1452 These DMA remapping devices are reported via ACPI tables
1453 and include PCI device scope covered by these DMA
1457 bool "Support for Graphics workaround"
1461 Current Graphics drivers tend to use physical address
1462 for DMA and avoid using DMA APIs. Setting this config
1463 option permits the IOMMU driver to set a unity map for
1464 all the OS-visible memory. Hence the driver can continue
1465 to use physical addresses for DMA.
1467 config DMAR_FLOPPY_WA
1472 Floppy disk drivers are know to bypass DMA API calls
1473 thereby failing to work when IOMMU is enabled. This
1474 workaround will setup a 1:1 mapping for the first
1475 16M to make floppy (an ISA device) work.
1477 source "drivers/pci/pcie/Kconfig"
1479 source "drivers/pci/Kconfig"
1481 # x86_64 have no ISA slots, but do have ISA-style DMA.
1490 depends on !(X86_VOYAGER || X86_VISWS)
1492 Find out whether you have ISA slots on your motherboard. ISA is the
1493 name of a bus system, i.e. the way the CPU talks to the other stuff
1494 inside your box. Other bus systems are PCI, EISA, MicroChannel
1495 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1496 newer boards don't support it. If you have ISA, say Y, otherwise N.
1502 The Extended Industry Standard Architecture (EISA) bus was
1503 developed as an open alternative to the IBM MicroChannel bus.
1505 The EISA bus provided some of the features of the IBM MicroChannel
1506 bus while maintaining backward compatibility with cards made for
1507 the older ISA bus. The EISA bus saw limited use between 1988 and
1508 1995 when it was made obsolete by the PCI bus.
1510 Say Y here if you are building a kernel for an EISA-based machine.
1514 source "drivers/eisa/Kconfig"
1517 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1518 default y if X86_VOYAGER
1520 MicroChannel Architecture is found in some IBM PS/2 machines and
1521 laptops. It is a bus system similar to PCI or ISA. See
1522 <file:Documentation/mca.txt> (and especially the web page given
1523 there) before attempting to build an MCA bus kernel.
1525 source "drivers/mca/Kconfig"
1528 tristate "NatSemi SCx200 support"
1529 depends on !X86_VOYAGER
1531 This provides basic support for National Semiconductor's
1532 (now AMD's) Geode processors. The driver probes for the
1533 PCI-IDs of several on-chip devices, so its a good dependency
1534 for other scx200_* drivers.
1536 If compiled as a module, the driver is named scx200.
1538 config SCx200HR_TIMER
1539 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1540 depends on SCx200 && GENERIC_TIME
1543 This driver provides a clocksource built upon the on-chip
1544 27MHz high-resolution timer. Its also a workaround for
1545 NSC Geode SC-1100's buggy TSC, which loses time when the
1546 processor goes idle (as is done by the scheduler). The
1547 other workaround is idle=poll boot option.
1549 config GEODE_MFGPT_TIMER
1550 bool "Geode Multi-Function General Purpose Timer (MFGPT) events"
1551 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1554 This driver provides a clock event source based on the MFGPT
1555 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1556 MFGPTs have a better resolution and max interval than the
1557 generic PIT, and are suitable for use as high-res timers.
1563 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1565 source "drivers/pcmcia/Kconfig"
1567 source "drivers/pci/hotplug/Kconfig"
1572 menu "Executable file formats / Emulations"
1574 source "fs/Kconfig.binfmt"
1576 config IA32_EMULATION
1577 bool "IA32 Emulation"
1580 Include code to run 32-bit programs under a 64-bit kernel. You should
1581 likely turn this on, unless you're 100% sure that you don't have any
1582 32-bit programs left.
1585 tristate "IA32 a.out support"
1586 depends on IA32_EMULATION
1588 Support old a.out binaries in the 32bit emulation.
1592 depends on IA32_EMULATION
1595 config COMPAT_FOR_U64_ALIGNMENT
1599 config SYSVIPC_COMPAT
1601 depends on X86_64 && COMPAT && SYSVIPC
1607 source "net/Kconfig"
1609 source "drivers/Kconfig"
1611 source "drivers/firmware/Kconfig"
1615 source "kernel/Kconfig.instrumentation"
1617 source "arch/x86/Kconfig.debug"
1619 source "security/Kconfig"
1621 source "crypto/Kconfig"
1623 source "lib/Kconfig"
git.openpandora.org / pandora-kernel.git / blob