3 bool "64-bit kernel" if ARCH = "x86"
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
18 select X86_DEV_DMA_OPS
19 select ARCH_USE_CMPXCHG_LOCKREF
24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
25 select ARCH_MIGHT_HAVE_PC_PARPORT
26 select HAVE_AOUT if X86_32
27 select HAVE_UNSTABLE_SCHED_CLOCK
28 select ARCH_SUPPORTS_NUMA_BALANCING
29 select ARCH_WANTS_PROT_NUMA_PROT_NONE
32 select HAVE_PCSPKR_PLATFORM
33 select HAVE_PERF_EVENTS
34 select HAVE_IOREMAP_PROT
37 select HAVE_MEMBLOCK_NODE_MAP
38 select ARCH_DISCARD_MEMBLOCK
39 select ARCH_WANT_OPTIONAL_GPIOLIB
40 select ARCH_WANT_FRAME_POINTERS
42 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
43 select HAVE_KRETPROBES
45 select HAVE_KPROBES_ON_FTRACE
46 select HAVE_FTRACE_MCOUNT_RECORD
47 select HAVE_FENTRY if X86_64
48 select HAVE_C_RECORDMCOUNT
49 select HAVE_DYNAMIC_FTRACE
50 select HAVE_DYNAMIC_FTRACE_WITH_REGS
51 select HAVE_FUNCTION_TRACER
52 select HAVE_FUNCTION_GRAPH_TRACER
53 select HAVE_FUNCTION_GRAPH_FP_TEST
54 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
55 select HAVE_SYSCALL_TRACEPOINTS
56 select SYSCTL_EXCEPTION_TRACE
59 select HAVE_ARCH_TRACEHOOK
60 select HAVE_GENERIC_DMA_COHERENT if X86_32
61 select HAVE_EFFICIENT_UNALIGNED_ACCESS
62 select USER_STACKTRACE_SUPPORT
63 select HAVE_REGS_AND_STACK_ACCESS_API
64 select HAVE_DMA_API_DEBUG
65 select HAVE_KERNEL_GZIP
66 select HAVE_KERNEL_BZIP2
67 select HAVE_KERNEL_LZMA
69 select HAVE_KERNEL_LZO
70 select HAVE_KERNEL_LZ4
71 select HAVE_HW_BREAKPOINT
72 select HAVE_MIXED_BREAKPOINTS_REGS
74 select HAVE_PERF_EVENTS_NMI
76 select HAVE_PERF_USER_STACK_DUMP
77 select HAVE_DEBUG_KMEMLEAK
79 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
80 select HAVE_CMPXCHG_LOCAL
81 select HAVE_CMPXCHG_DOUBLE
82 select HAVE_ARCH_KMEMCHECK
83 select HAVE_USER_RETURN_NOTIFIER
84 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
85 select HAVE_ARCH_JUMP_LABEL
86 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
88 select GENERIC_FIND_FIRST_BIT
89 select GENERIC_IRQ_PROBE
90 select GENERIC_PENDING_IRQ if SMP
91 select GENERIC_IRQ_SHOW
92 select GENERIC_CLOCKEVENTS_MIN_ADJUST
93 select IRQ_FORCED_THREADING
94 select USE_GENERIC_SMP_HELPERS if SMP
95 select HAVE_BPF_JIT if X86_64
96 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
98 select ARCH_HAVE_NMI_SAFE_CMPXCHG
100 select DCACHE_WORD_ACCESS
101 select GENERIC_SMP_IDLE_THREAD
102 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
103 select HAVE_ARCH_SECCOMP_FILTER
104 select BUILDTIME_EXTABLE_SORT
105 select GENERIC_CMOS_UPDATE
106 select HAVE_ARCH_SOFT_DIRTY
107 select CLOCKSOURCE_WATCHDOG
108 select GENERIC_CLOCKEVENTS
109 select ARCH_CLOCKSOURCE_DATA if X86_64
110 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
111 select GENERIC_TIME_VSYSCALL if X86_64
112 select KTIME_SCALAR if X86_32
113 select GENERIC_STRNCPY_FROM_USER
114 select GENERIC_STRNLEN_USER
115 select HAVE_CONTEXT_TRACKING if X86_64
116 select HAVE_IRQ_TIME_ACCOUNTING
118 select MODULES_USE_ELF_REL if X86_32
119 select MODULES_USE_ELF_RELA if X86_64
120 select CLONE_BACKWARDS if X86_32
121 select ARCH_USE_BUILTIN_BSWAP
122 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
123 select OLD_SIGACTION if X86_32
124 select COMPAT_OLD_SIGACTION if IA32_EMULATION
126 select HAVE_DEBUG_STACKOVERFLOW
127 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
129 config INSTRUCTION_DECODER
131 depends on KPROBES || PERF_EVENTS || UPROBES
135 default "elf32-i386" if X86_32
136 default "elf64-x86-64" if X86_64
138 config ARCH_DEFCONFIG
140 default "arch/x86/configs/i386_defconfig" if X86_32
141 default "arch/x86/configs/x86_64_defconfig" if X86_64
143 config LOCKDEP_SUPPORT
146 config STACKTRACE_SUPPORT
149 config HAVE_LATENCYTOP_SUPPORT
158 config NEED_DMA_MAP_STATE
160 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
162 config NEED_SG_DMA_LENGTH
165 config GENERIC_ISA_DMA
167 depends on ISA_DMA_API
172 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
174 config GENERIC_BUG_RELATIVE_POINTERS
177 config GENERIC_HWEIGHT
180 config ARCH_MAY_HAVE_PC_FDC
182 depends on ISA_DMA_API
184 config RWSEM_XCHGADD_ALGORITHM
187 config GENERIC_CALIBRATE_DELAY
190 config ARCH_HAS_CPU_RELAX
193 config ARCH_HAS_CACHE_LINE_SIZE
196 config ARCH_HAS_CPU_AUTOPROBE
199 config HAVE_SETUP_PER_CPU_AREA
202 config NEED_PER_CPU_EMBED_FIRST_CHUNK
205 config NEED_PER_CPU_PAGE_FIRST_CHUNK
208 config ARCH_HIBERNATION_POSSIBLE
211 config ARCH_SUSPEND_POSSIBLE
214 config ARCH_WANT_HUGE_PMD_SHARE
217 config ARCH_WANT_GENERAL_HUGETLB
228 config ARCH_SUPPORTS_OPTIMIZED_INLINING
231 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
234 config HAVE_INTEL_TXT
236 depends on INTEL_IOMMU && ACPI
240 depends on X86_32 && SMP
244 depends on X86_64 && SMP
250 config X86_32_LAZY_GS
252 depends on X86_32 && !CC_STACKPROTECTOR
254 config ARCH_HWEIGHT_CFLAGS
256 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
257 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
259 config ARCH_SUPPORTS_UPROBES
262 source "init/Kconfig"
263 source "kernel/Kconfig.freezer"
265 menu "Processor type and features"
268 bool "DMA memory allocation support" if EXPERT
271 DMA memory allocation support allows devices with less than 32-bit
272 addressing to allocate within the first 16MB of address space.
273 Disable if no such devices will be used.
278 bool "Symmetric multi-processing support"
280 This enables support for systems with more than one CPU. If you have
281 a system with only one CPU, like most personal computers, say N. If
282 you have a system with more than one CPU, say Y.
284 If you say N here, the kernel will run on single and multiprocessor
285 machines, but will use only one CPU of a multiprocessor machine. If
286 you say Y here, the kernel will run on many, but not all,
287 singleprocessor machines. On a singleprocessor machine, the kernel
288 will run faster if you say N here.
290 Note that if you say Y here and choose architecture "586" or
291 "Pentium" under "Processor family", the kernel will not work on 486
292 architectures. Similarly, multiprocessor kernels for the "PPro"
293 architecture may not work on all Pentium based boards.
295 People using multiprocessor machines who say Y here should also say
296 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
297 Management" code will be disabled if you say Y here.
299 See also <file:Documentation/x86/i386/IO-APIC.txt>,
300 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
301 <http://www.tldp.org/docs.html#howto>.
303 If you don't know what to do here, say N.
306 bool "Support x2apic"
307 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
309 This enables x2apic support on CPUs that have this feature.
311 This allows 32-bit apic IDs (so it can support very large systems),
312 and accesses the local apic via MSRs not via mmio.
314 If you don't know what to do here, say N.
317 bool "Enable MPS table" if ACPI || SFI
319 depends on X86_LOCAL_APIC
321 For old smp systems that do not have proper acpi support. Newer systems
322 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
325 bool "Support for big SMP systems with more than 8 CPUs"
326 depends on X86_32 && SMP
328 This option is needed for the systems that have more than 8 CPUs
332 depends on X86_GOLDFISH
335 config X86_EXTENDED_PLATFORM
336 bool "Support for extended (non-PC) x86 platforms"
339 If you disable this option then the kernel will only support
340 standard PC platforms. (which covers the vast majority of
343 If you enable this option then you'll be able to select support
344 for the following (non-PC) 32 bit x86 platforms:
345 Goldfish (Android emulator)
349 SGI 320/540 (Visual Workstation)
350 STA2X11-based (e.g. Northville)
351 Summit/EXA (IBM x440)
352 Unisys ES7000 IA32 series
353 Moorestown MID devices
355 If you have one of these systems, or if you want to build a
356 generic distribution kernel, say Y here - otherwise say N.
360 config X86_EXTENDED_PLATFORM
361 bool "Support for extended (non-PC) x86 platforms"
364 If you disable this option then the kernel will only support
365 standard PC platforms. (which covers the vast majority of
368 If you enable this option then you'll be able to select support
369 for the following (non-PC) 64 bit x86 platforms:
374 If you have one of these systems, or if you want to build a
375 generic distribution kernel, say Y here - otherwise say N.
377 # This is an alphabetically sorted list of 64 bit extended platforms
378 # Please maintain the alphabetic order if and when there are additions
380 bool "Numascale NumaChip"
382 depends on X86_EXTENDED_PLATFORM
385 depends on X86_X2APIC
386 depends on PCI_MMCONFIG
388 Adds support for Numascale NumaChip large-SMP systems. Needed to
389 enable more than ~168 cores.
390 If you don't have one of these, you should say N here.
394 select HYPERVISOR_GUEST
396 depends on X86_64 && PCI
397 depends on X86_EXTENDED_PLATFORM
400 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
401 supposed to run on these EM64T-based machines. Only choose this option
402 if you have one of these machines.
405 bool "SGI Ultraviolet"
407 depends on X86_EXTENDED_PLATFORM
409 depends on X86_X2APIC
411 This option is needed in order to support SGI Ultraviolet systems.
412 If you don't have one of these, you should say N here.
414 # Following is an alphabetically sorted list of 32 bit extended platforms
415 # Please maintain the alphabetic order if and when there are additions
418 bool "Goldfish (Virtual Platform)"
420 depends on X86_EXTENDED_PLATFORM
422 Enable support for the Goldfish virtual platform used primarily
423 for Android development. Unless you are building for the Android
424 Goldfish emulator say N here.
427 bool "CE4100 TV platform"
429 depends on PCI_GODIRECT
431 depends on X86_EXTENDED_PLATFORM
432 select X86_REBOOTFIXUPS
434 select OF_EARLY_FLATTREE
437 Select for the Intel CE media processor (CE4100) SOC.
438 This option compiles in support for the CE4100 SOC for settop
439 boxes and media devices.
441 config X86_WANT_INTEL_MID
442 bool "Intel MID platform support"
444 depends on X86_EXTENDED_PLATFORM
446 Select to build a kernel capable of supporting Intel MID platform
447 systems which do not have the PCI legacy interfaces (Moorestown,
448 Medfield). If you are building for a PC class system say N here.
450 if X86_WANT_INTEL_MID
456 bool "Medfield MID platform"
459 depends on X86_IO_APIC
467 select X86_PLATFORM_DEVICES
468 select MFD_INTEL_MSIC
470 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
471 Internet Device(MID) platform.
472 Unlike standard x86 PCs, Medfield does not have many legacy devices
473 nor standard legacy replacement devices/features. e.g. Medfield does
474 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
478 config X86_INTEL_LPSS
479 bool "Intel Low Power Subsystem Support"
484 Select to build support for Intel Low Power Subsystem such as
485 found on Intel Lynxpoint PCH. Selecting this option enables
486 things like clock tree (common clock framework) and pincontrol
487 which are needed by the LPSS peripheral drivers.
490 bool "RDC R-321x SoC"
492 depends on X86_EXTENDED_PLATFORM
494 select X86_REBOOTFIXUPS
496 This option is needed for RDC R-321x system-on-chip, also known
498 If you don't have one of these chips, you should say N here.
500 config X86_32_NON_STANDARD
501 bool "Support non-standard 32-bit SMP architectures"
502 depends on X86_32 && SMP
503 depends on X86_EXTENDED_PLATFORM
505 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
506 STA2X11, default subarchitectures. It is intended for a generic
507 binary kernel. If you select them all, kernel will probe it
508 one by one and will fallback to default.
510 # Alphabetically sorted list of Non standard 32 bit platforms
513 bool "NUMAQ (IBM/Sequent)"
514 depends on X86_32_NON_STANDARD
519 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
520 NUMA multiquad box. This changes the way that processors are
521 bootstrapped, and uses Clustered Logical APIC addressing mode instead
522 of Flat Logical. You will need a new lynxer.elf file to flash your
523 firmware with - send email to <Martin.Bligh@us.ibm.com>.
525 config X86_SUPPORTS_MEMORY_FAILURE
527 # MCE code calls memory_failure():
529 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
530 depends on !X86_NUMAQ
531 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
532 depends on X86_64 || !SPARSEMEM
533 select ARCH_SUPPORTS_MEMORY_FAILURE
536 bool "SGI 320/540 (Visual Workstation)"
537 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
538 depends on X86_32_NON_STANDARD
540 The SGI Visual Workstation series is an IA32-based workstation
541 based on SGI systems chips with some legacy PC hardware attached.
543 Say Y here to create a kernel to run on the SGI 320 or 540.
545 A kernel compiled for the Visual Workstation will run on general
546 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
549 bool "STA2X11 Companion Chip Support"
550 depends on X86_32_NON_STANDARD && PCI
551 select X86_DEV_DMA_OPS
555 select ARCH_REQUIRE_GPIOLIB
558 This adds support for boards based on the STA2X11 IO-Hub,
559 a.k.a. "ConneXt". The chip is used in place of the standard
560 PC chipset, so all "standard" peripherals are missing. If this
561 option is selected the kernel will still be able to boot on
562 standard PC machines.
565 bool "Summit/EXA (IBM x440)"
566 depends on X86_32_NON_STANDARD
568 This option is needed for IBM systems that use the Summit/EXA chipset.
569 In particular, it is needed for the x440.
572 bool "Unisys ES7000 IA32 series"
573 depends on X86_32_NON_STANDARD && X86_BIGSMP
575 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
576 supposed to run on an IA32-based Unisys ES7000 system.
579 tristate "Eurobraille/Iris poweroff module"
582 The Iris machines from EuroBraille do not have APM or ACPI support
583 to shut themselves down properly. A special I/O sequence is
584 needed to do so, which is what this module does at
587 This is only for Iris machines from EuroBraille.
591 config SCHED_OMIT_FRAME_POINTER
593 prompt "Single-depth WCHAN output"
596 Calculate simpler /proc/<PID>/wchan values. If this option
597 is disabled then wchan values will recurse back to the
598 caller function. This provides more accurate wchan values,
599 at the expense of slightly more scheduling overhead.
601 If in doubt, say "Y".
603 menuconfig HYPERVISOR_GUEST
604 bool "Linux guest support"
606 Say Y here to enable options for running Linux under various hyper-
607 visors. This option enables basic hypervisor detection and platform
610 If you say N, all options in this submenu will be skipped and
611 disabled, and Linux guest support won't be built in.
616 bool "Enable paravirtualization code"
618 This changes the kernel so it can modify itself when it is run
619 under a hypervisor, potentially improving performance significantly
620 over full virtualization. However, when run without a hypervisor
621 the kernel is theoretically slower and slightly larger.
623 config PARAVIRT_DEBUG
624 bool "paravirt-ops debugging"
625 depends on PARAVIRT && DEBUG_KERNEL
627 Enable to debug paravirt_ops internals. Specifically, BUG if
628 a paravirt_op is missing when it is called.
630 config PARAVIRT_SPINLOCKS
631 bool "Paravirtualization layer for spinlocks"
632 depends on PARAVIRT && SMP
633 select UNINLINE_SPIN_UNLOCK
635 Paravirtualized spinlocks allow a pvops backend to replace the
636 spinlock implementation with something virtualization-friendly
637 (for example, block the virtual CPU rather than spinning).
639 Unfortunately the downside is an up to 5% performance hit on
640 native kernels, with various workloads.
642 If you are unsure how to answer this question, answer N.
644 source "arch/x86/xen/Kconfig"
647 bool "KVM Guest support (including kvmclock)"
649 select PARAVIRT_CLOCK
652 This option enables various optimizations for running under the KVM
653 hypervisor. It includes a paravirtualized clock, so that instead
654 of relying on a PIT (or probably other) emulation by the
655 underlying device model, the host provides the guest with
656 timing infrastructure such as time of day, and system time
659 bool "Enable debug information for KVM Guests in debugfs"
660 depends on KVM_GUEST && DEBUG_FS
663 This option enables collection of various statistics for KVM guest.
664 Statistics are displayed in debugfs filesystem. Enabling this option
665 may incur significant overhead.
667 source "arch/x86/lguest/Kconfig"
669 config PARAVIRT_TIME_ACCOUNTING
670 bool "Paravirtual steal time accounting"
674 Select this option to enable fine granularity task steal time
675 accounting. Time spent executing other tasks in parallel with
676 the current vCPU is discounted from the vCPU power. To account for
677 that, there can be a small performance impact.
679 If in doubt, say N here.
681 config PARAVIRT_CLOCK
684 endif #HYPERVISOR_GUEST
692 This option adds a kernel parameter 'memtest', which allows memtest
694 memtest=0, mean disabled; -- default
695 memtest=1, mean do 1 test pattern;
697 memtest=4, mean do 4 test patterns.
698 If you are unsure how to answer this question, answer N.
700 config X86_SUMMIT_NUMA
702 depends on X86_32 && NUMA && X86_32_NON_STANDARD
704 config X86_CYCLONE_TIMER
706 depends on X86_SUMMIT
708 source "arch/x86/Kconfig.cpu"
712 prompt "HPET Timer Support" if X86_32
714 Use the IA-PC HPET (High Precision Event Timer) to manage
715 time in preference to the PIT and RTC, if a HPET is
717 HPET is the next generation timer replacing legacy 8254s.
718 The HPET provides a stable time base on SMP
719 systems, unlike the TSC, but it is more expensive to access,
720 as it is off-chip. You can find the HPET spec at
721 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
723 You can safely choose Y here. However, HPET will only be
724 activated if the platform and the BIOS support this feature.
725 Otherwise the 8254 will be used for timing services.
727 Choose N to continue using the legacy 8254 timer.
729 config HPET_EMULATE_RTC
731 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
734 def_bool y if X86_INTEL_MID
735 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
737 depends on X86_INTEL_MID && SFI
739 APB timer is the replacement for 8254, HPET on X86 MID platforms.
740 The APBT provides a stable time base on SMP
741 systems, unlike the TSC, but it is more expensive to access,
742 as it is off-chip. APB timers are always running regardless of CPU
743 C states, they are used as per CPU clockevent device when possible.
745 # Mark as expert because too many people got it wrong.
746 # The code disables itself when not needed.
749 bool "Enable DMI scanning" if EXPERT
751 Enabled scanning of DMI to identify machine quirks. Say Y
752 here unless you have verified that your setup is not
753 affected by entries in the DMI blacklist. Required by PNP
757 bool "Old AMD GART IOMMU support"
759 depends on X86_64 && PCI && AMD_NB
761 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
762 GART based hardware IOMMUs.
764 The GART supports full DMA access for devices with 32-bit access
765 limitations, on systems with more than 3 GB. This is usually needed
766 for USB, sound, many IDE/SATA chipsets and some other devices.
768 Newer systems typically have a modern AMD IOMMU, supported via
769 the CONFIG_AMD_IOMMU=y config option.
771 In normal configurations this driver is only active when needed:
772 there's more than 3 GB of memory and the system contains a
773 32-bit limited device.
778 bool "IBM Calgary IOMMU support"
780 depends on X86_64 && PCI
782 Support for hardware IOMMUs in IBM's xSeries x366 and x460
783 systems. Needed to run systems with more than 3GB of memory
784 properly with 32-bit PCI devices that do not support DAC
785 (Double Address Cycle). Calgary also supports bus level
786 isolation, where all DMAs pass through the IOMMU. This
787 prevents them from going anywhere except their intended
788 destination. This catches hard-to-find kernel bugs and
789 mis-behaving drivers and devices that do not use the DMA-API
790 properly to set up their DMA buffers. The IOMMU can be
791 turned off at boot time with the iommu=off parameter.
792 Normally the kernel will make the right choice by itself.
795 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
797 prompt "Should Calgary be enabled by default?"
798 depends on CALGARY_IOMMU
800 Should Calgary be enabled by default? if you choose 'y', Calgary
801 will be used (if it exists). If you choose 'n', Calgary will not be
802 used even if it exists. If you choose 'n' and would like to use
803 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
806 # need this always selected by IOMMU for the VIA workaround
810 Support for software bounce buffers used on x86-64 systems
811 which don't have a hardware IOMMU. Using this PCI devices
812 which can only access 32-bits of memory can be used on systems
813 with more than 3 GB of memory.
818 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
821 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
822 depends on X86_64 && SMP && DEBUG_KERNEL
823 select CPUMASK_OFFSTACK
825 Enable maximum number of CPUS and NUMA Nodes for this architecture.
829 int "Maximum number of CPUs" if SMP && !MAXSMP
830 range 2 8 if SMP && X86_32 && !X86_BIGSMP
831 range 2 512 if SMP && !MAXSMP
833 default "4096" if MAXSMP
834 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
837 This allows you to specify the maximum number of CPUs which this
838 kernel will support. The maximum supported value is 512 and the
839 minimum value which makes sense is 2.
841 This is purely to save memory - each supported CPU adds
842 approximately eight kilobytes to the kernel image.
845 bool "SMT (Hyperthreading) scheduler support"
848 SMT scheduler support improves the CPU scheduler's decision making
849 when dealing with Intel Pentium 4 chips with HyperThreading at a
850 cost of slightly increased overhead in some places. If unsure say
855 prompt "Multi-core scheduler support"
858 Multi-core scheduler support improves the CPU scheduler's decision
859 making when dealing with multi-core CPU chips at a cost of slightly
860 increased overhead in some places. If unsure say N here.
862 source "kernel/Kconfig.preempt"
865 bool "Local APIC support on uniprocessors"
866 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
868 A local APIC (Advanced Programmable Interrupt Controller) is an
869 integrated interrupt controller in the CPU. If you have a single-CPU
870 system which has a processor with a local APIC, you can say Y here to
871 enable and use it. If you say Y here even though your machine doesn't
872 have a local APIC, then the kernel will still run with no slowdown at
873 all. The local APIC supports CPU-generated self-interrupts (timer,
874 performance counters), and the NMI watchdog which detects hard
878 bool "IO-APIC support on uniprocessors"
879 depends on X86_UP_APIC
881 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
882 SMP-capable replacement for PC-style interrupt controllers. Most
883 SMP systems and many recent uniprocessor systems have one.
885 If you have a single-CPU system with an IO-APIC, you can say Y here
886 to use it. If you say Y here even though your machine doesn't have
887 an IO-APIC, then the kernel will still run with no slowdown at all.
889 config X86_LOCAL_APIC
891 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
895 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
897 config X86_VISWS_APIC
899 depends on X86_32 && X86_VISWS
901 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
902 bool "Reroute for broken boot IRQs"
903 depends on X86_IO_APIC
905 This option enables a workaround that fixes a source of
906 spurious interrupts. This is recommended when threaded
907 interrupt handling is used on systems where the generation of
908 superfluous "boot interrupts" cannot be disabled.
910 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
911 entry in the chipset's IO-APIC is masked (as, e.g. the RT
912 kernel does during interrupt handling). On chipsets where this
913 boot IRQ generation cannot be disabled, this workaround keeps
914 the original IRQ line masked so that only the equivalent "boot
915 IRQ" is delivered to the CPUs. The workaround also tells the
916 kernel to set up the IRQ handler on the boot IRQ line. In this
917 way only one interrupt is delivered to the kernel. Otherwise
918 the spurious second interrupt may cause the kernel to bring
919 down (vital) interrupt lines.
921 Only affects "broken" chipsets. Interrupt sharing may be
922 increased on these systems.
925 bool "Machine Check / overheating reporting"
928 Machine Check support allows the processor to notify the
929 kernel if it detects a problem (e.g. overheating, data corruption).
930 The action the kernel takes depends on the severity of the problem,
931 ranging from warning messages to halting the machine.
935 prompt "Intel MCE features"
936 depends on X86_MCE && X86_LOCAL_APIC
938 Additional support for intel specific MCE features such as
943 prompt "AMD MCE features"
944 depends on X86_MCE && X86_LOCAL_APIC
946 Additional support for AMD specific MCE features such as
947 the DRAM Error Threshold.
949 config X86_ANCIENT_MCE
950 bool "Support for old Pentium 5 / WinChip machine checks"
951 depends on X86_32 && X86_MCE
953 Include support for machine check handling on old Pentium 5 or WinChip
954 systems. These typically need to be enabled explicitely on the command
957 config X86_MCE_THRESHOLD
958 depends on X86_MCE_AMD || X86_MCE_INTEL
961 config X86_MCE_INJECT
963 tristate "Machine check injector support"
965 Provide support for injecting machine checks for testing purposes.
966 If you don't know what a machine check is and you don't do kernel
967 QA it is safe to say n.
969 config X86_THERMAL_VECTOR
971 depends on X86_MCE_INTEL
974 bool "Enable VM86 support" if EXPERT
978 This option is required by programs like DOSEMU to run 16-bit legacy
979 code on X86 processors. It also may be needed by software like
980 XFree86 to initialize some video cards via BIOS. Disabling this
981 option saves about 6k.
984 tristate "Toshiba Laptop support"
987 This adds a driver to safely access the System Management Mode of
988 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
989 not work on models with a Phoenix BIOS. The System Management Mode
990 is used to set the BIOS and power saving options on Toshiba portables.
992 For information on utilities to make use of this driver see the
993 Toshiba Linux utilities web site at:
994 <http://www.buzzard.org.uk/toshiba/>.
996 Say Y if you intend to run this kernel on a Toshiba portable.
1000 tristate "Dell laptop support"
1003 This adds a driver to safely access the System Management Mode
1004 of the CPU on the Dell Inspiron 8000. The System Management Mode
1005 is used to read cpu temperature and cooling fan status and to
1006 control the fans on the I8K portables.
1008 This driver has been tested only on the Inspiron 8000 but it may
1009 also work with other Dell laptops. You can force loading on other
1010 models by passing the parameter `force=1' to the module. Use at
1013 For information on utilities to make use of this driver see the
1014 I8K Linux utilities web site at:
1015 <http://people.debian.org/~dz/i8k/>
1017 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1020 config X86_REBOOTFIXUPS
1021 bool "Enable X86 board specific fixups for reboot"
1024 This enables chipset and/or board specific fixups to be done
1025 in order to get reboot to work correctly. This is only needed on
1026 some combinations of hardware and BIOS. The symptom, for which
1027 this config is intended, is when reboot ends with a stalled/hung
1030 Currently, the only fixup is for the Geode machines using
1031 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1033 Say Y if you want to enable the fixup. Currently, it's safe to
1034 enable this option even if you don't need it.
1038 tristate "CPU microcode loading support"
1039 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1043 If you say Y here, you will be able to update the microcode on
1044 certain Intel and AMD processors. The Intel support is for the
1045 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1046 Xeon etc. The AMD support is for families 0x10 and later. You will
1047 obviously need the actual microcode binary data itself which is not
1048 shipped with the Linux kernel.
1050 This option selects the general module only, you need to select
1051 at least one vendor specific module as well.
1053 To compile this driver as a module, choose M here: the module
1054 will be called microcode.
1056 config MICROCODE_INTEL
1057 bool "Intel microcode loading support"
1058 depends on MICROCODE
1062 This options enables microcode patch loading support for Intel
1065 For latest news and information on obtaining all the required
1066 Intel ingredients for this driver, check:
1067 <http://www.urbanmyth.org/microcode/>.
1069 config MICROCODE_AMD
1070 bool "AMD microcode loading support"
1071 depends on MICROCODE
1074 If you select this option, microcode patch loading support for AMD
1075 processors will be enabled.
1077 config MICROCODE_OLD_INTERFACE
1079 depends on MICROCODE
1081 config MICROCODE_INTEL_LIB
1083 depends on MICROCODE_INTEL
1085 config MICROCODE_INTEL_EARLY
1088 config MICROCODE_AMD_EARLY
1091 config MICROCODE_EARLY
1092 bool "Early load microcode"
1093 depends on MICROCODE=y && BLK_DEV_INITRD
1094 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1095 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1098 This option provides functionality to read additional microcode data
1099 at the beginning of initrd image. The data tells kernel to load
1100 microcode to CPU's as early as possible. No functional change if no
1101 microcode data is glued to the initrd, therefore it's safe to say Y.
1104 tristate "/dev/cpu/*/msr - Model-specific register support"
1106 This device gives privileged processes access to the x86
1107 Model-Specific Registers (MSRs). It is a character device with
1108 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1109 MSR accesses are directed to a specific CPU on multi-processor
1113 tristate "/dev/cpu/*/cpuid - CPU information support"
1115 This device gives processes access to the x86 CPUID instruction to
1116 be executed on a specific processor. It is a character device
1117 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1121 prompt "High Memory Support"
1122 default HIGHMEM64G if X86_NUMAQ
1128 depends on !X86_NUMAQ
1130 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1131 However, the address space of 32-bit x86 processors is only 4
1132 Gigabytes large. That means that, if you have a large amount of
1133 physical memory, not all of it can be "permanently mapped" by the
1134 kernel. The physical memory that's not permanently mapped is called
1137 If you are compiling a kernel which will never run on a machine with
1138 more than 1 Gigabyte total physical RAM, answer "off" here (default
1139 choice and suitable for most users). This will result in a "3GB/1GB"
1140 split: 3GB are mapped so that each process sees a 3GB virtual memory
1141 space and the remaining part of the 4GB virtual memory space is used
1142 by the kernel to permanently map as much physical memory as
1145 If the machine has between 1 and 4 Gigabytes physical RAM, then
1148 If more than 4 Gigabytes is used then answer "64GB" here. This
1149 selection turns Intel PAE (Physical Address Extension) mode on.
1150 PAE implements 3-level paging on IA32 processors. PAE is fully
1151 supported by Linux, PAE mode is implemented on all recent Intel
1152 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1153 then the kernel will not boot on CPUs that don't support PAE!
1155 The actual amount of total physical memory will either be
1156 auto detected or can be forced by using a kernel command line option
1157 such as "mem=256M". (Try "man bootparam" or see the documentation of
1158 your boot loader (lilo or loadlin) about how to pass options to the
1159 kernel at boot time.)
1161 If unsure, say "off".
1165 depends on !X86_NUMAQ
1167 Select this if you have a 32-bit processor and between 1 and 4
1168 gigabytes of physical RAM.
1175 Select this if you have a 32-bit processor and more than 4
1176 gigabytes of physical RAM.
1181 prompt "Memory split" if EXPERT
1185 Select the desired split between kernel and user memory.
1187 If the address range available to the kernel is less than the
1188 physical memory installed, the remaining memory will be available
1189 as "high memory". Accessing high memory is a little more costly
1190 than low memory, as it needs to be mapped into the kernel first.
1191 Note that increasing the kernel address space limits the range
1192 available to user programs, making the address space there
1193 tighter. Selecting anything other than the default 3G/1G split
1194 will also likely make your kernel incompatible with binary-only
1197 If you are not absolutely sure what you are doing, leave this
1201 bool "3G/1G user/kernel split"
1202 config VMSPLIT_3G_OPT
1204 bool "3G/1G user/kernel split (for full 1G low memory)"
1206 bool "2G/2G user/kernel split"
1207 config VMSPLIT_2G_OPT
1209 bool "2G/2G user/kernel split (for full 2G low memory)"
1211 bool "1G/3G user/kernel split"
1216 default 0xB0000000 if VMSPLIT_3G_OPT
1217 default 0x80000000 if VMSPLIT_2G
1218 default 0x78000000 if VMSPLIT_2G_OPT
1219 default 0x40000000 if VMSPLIT_1G
1225 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1228 bool "PAE (Physical Address Extension) Support"
1229 depends on X86_32 && !HIGHMEM4G
1231 PAE is required for NX support, and furthermore enables
1232 larger swapspace support for non-overcommit purposes. It
1233 has the cost of more pagetable lookup overhead, and also
1234 consumes more pagetable space per process.
1236 config ARCH_PHYS_ADDR_T_64BIT
1238 depends on X86_64 || X86_PAE
1240 config ARCH_DMA_ADDR_T_64BIT
1242 depends on X86_64 || HIGHMEM64G
1244 config DIRECT_GBPAGES
1245 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1249 Allow the kernel linear mapping to use 1GB pages on CPUs that
1250 support it. This can improve the kernel's performance a tiny bit by
1251 reducing TLB pressure. If in doubt, say "Y".
1253 # Common NUMA Features
1255 bool "Numa Memory Allocation and Scheduler Support"
1257 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1258 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1260 Enable NUMA (Non Uniform Memory Access) support.
1262 The kernel will try to allocate memory used by a CPU on the
1263 local memory controller of the CPU and add some more
1264 NUMA awareness to the kernel.
1266 For 64-bit this is recommended if the system is Intel Core i7
1267 (or later), AMD Opteron, or EM64T NUMA.
1269 For 32-bit this is only needed on (rare) 32-bit-only platforms
1270 that support NUMA topologies, such as NUMAQ / Summit, or if you
1271 boot a 32-bit kernel on a 64-bit NUMA platform.
1273 Otherwise, you should say N.
1275 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1276 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1280 prompt "Old style AMD Opteron NUMA detection"
1281 depends on X86_64 && NUMA && PCI
1283 Enable AMD NUMA node topology detection. You should say Y here if
1284 you have a multi processor AMD system. This uses an old method to
1285 read the NUMA configuration directly from the builtin Northbridge
1286 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1287 which also takes priority if both are compiled in.
1289 config X86_64_ACPI_NUMA
1291 prompt "ACPI NUMA detection"
1292 depends on X86_64 && NUMA && ACPI && PCI
1295 Enable ACPI SRAT based node topology detection.
1297 # Some NUMA nodes have memory ranges that span
1298 # other nodes. Even though a pfn is valid and
1299 # between a node's start and end pfns, it may not
1300 # reside on that node. See memmap_init_zone()
1302 config NODES_SPAN_OTHER_NODES
1304 depends on X86_64_ACPI_NUMA
1307 bool "NUMA emulation"
1310 Enable NUMA emulation. A flat machine will be split
1311 into virtual nodes when booted with "numa=fake=N", where N is the
1312 number of nodes. This is only useful for debugging.
1315 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1317 default "10" if MAXSMP
1318 default "6" if X86_64
1319 default "4" if X86_NUMAQ
1321 depends on NEED_MULTIPLE_NODES
1323 Specify the maximum number of NUMA Nodes available on the target
1324 system. Increases memory reserved to accommodate various tables.
1326 config ARCH_HAVE_MEMORY_PRESENT
1328 depends on X86_32 && DISCONTIGMEM
1330 config NEED_NODE_MEMMAP_SIZE
1332 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1334 config ARCH_FLATMEM_ENABLE
1336 depends on X86_32 && !NUMA
1338 config ARCH_DISCONTIGMEM_ENABLE
1340 depends on NUMA && X86_32
1342 config ARCH_DISCONTIGMEM_DEFAULT
1344 depends on NUMA && X86_32
1346 config ARCH_SPARSEMEM_ENABLE
1348 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1349 select SPARSEMEM_STATIC if X86_32
1350 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1352 config ARCH_SPARSEMEM_DEFAULT
1356 config ARCH_SELECT_MEMORY_MODEL
1358 depends on ARCH_SPARSEMEM_ENABLE
1360 config ARCH_MEMORY_PROBE
1361 bool "Enable sysfs memory/probe interface"
1362 depends on X86_64 && MEMORY_HOTPLUG
1364 This option enables a sysfs memory/probe interface for testing.
1365 See Documentation/memory-hotplug.txt for more information.
1366 If you are unsure how to answer this question, answer N.
1368 config ARCH_PROC_KCORE_TEXT
1370 depends on X86_64 && PROC_KCORE
1372 config ILLEGAL_POINTER_VALUE
1375 default 0xdead000000000000 if X86_64
1380 bool "Allocate 3rd-level pagetables from highmem"
1383 The VM uses one page table entry for each page of physical memory.
1384 For systems with a lot of RAM, this can be wasteful of precious
1385 low memory. Setting this option will put user-space page table
1386 entries in high memory.
1388 config X86_CHECK_BIOS_CORRUPTION
1389 bool "Check for low memory corruption"
1391 Periodically check for memory corruption in low memory, which
1392 is suspected to be caused by BIOS. Even when enabled in the
1393 configuration, it is disabled at runtime. Enable it by
1394 setting "memory_corruption_check=1" on the kernel command
1395 line. By default it scans the low 64k of memory every 60
1396 seconds; see the memory_corruption_check_size and
1397 memory_corruption_check_period parameters in
1398 Documentation/kernel-parameters.txt to adjust this.
1400 When enabled with the default parameters, this option has
1401 almost no overhead, as it reserves a relatively small amount
1402 of memory and scans it infrequently. It both detects corruption
1403 and prevents it from affecting the running system.
1405 It is, however, intended as a diagnostic tool; if repeatable
1406 BIOS-originated corruption always affects the same memory,
1407 you can use memmap= to prevent the kernel from using that
1410 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1411 bool "Set the default setting of memory_corruption_check"
1412 depends on X86_CHECK_BIOS_CORRUPTION
1415 Set whether the default state of memory_corruption_check is
1418 config X86_RESERVE_LOW
1419 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1423 Specify the amount of low memory to reserve for the BIOS.
1425 The first page contains BIOS data structures that the kernel
1426 must not use, so that page must always be reserved.
1428 By default we reserve the first 64K of physical RAM, as a
1429 number of BIOSes are known to corrupt that memory range
1430 during events such as suspend/resume or monitor cable
1431 insertion, so it must not be used by the kernel.
1433 You can set this to 4 if you are absolutely sure that you
1434 trust the BIOS to get all its memory reservations and usages
1435 right. If you know your BIOS have problems beyond the
1436 default 64K area, you can set this to 640 to avoid using the
1437 entire low memory range.
1439 If you have doubts about the BIOS (e.g. suspend/resume does
1440 not work or there's kernel crashes after certain hardware
1441 hotplug events) then you might want to enable
1442 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1443 typical corruption patterns.
1445 Leave this to the default value of 64 if you are unsure.
1447 config MATH_EMULATION
1449 prompt "Math emulation" if X86_32
1451 Linux can emulate a math coprocessor (used for floating point
1452 operations) if you don't have one. 486DX and Pentium processors have
1453 a math coprocessor built in, 486SX and 386 do not, unless you added
1454 a 487DX or 387, respectively. (The messages during boot time can
1455 give you some hints here ["man dmesg"].) Everyone needs either a
1456 coprocessor or this emulation.
1458 If you don't have a math coprocessor, you need to say Y here; if you
1459 say Y here even though you have a coprocessor, the coprocessor will
1460 be used nevertheless. (This behavior can be changed with the kernel
1461 command line option "no387", which comes handy if your coprocessor
1462 is broken. Try "man bootparam" or see the documentation of your boot
1463 loader (lilo or loadlin) about how to pass options to the kernel at
1464 boot time.) This means that it is a good idea to say Y here if you
1465 intend to use this kernel on different machines.
1467 More information about the internals of the Linux math coprocessor
1468 emulation can be found in <file:arch/x86/math-emu/README>.
1470 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1471 kernel, it won't hurt.
1475 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1477 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1478 the Memory Type Range Registers (MTRRs) may be used to control
1479 processor access to memory ranges. This is most useful if you have
1480 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1481 allows bus write transfers to be combined into a larger transfer
1482 before bursting over the PCI/AGP bus. This can increase performance
1483 of image write operations 2.5 times or more. Saying Y here creates a
1484 /proc/mtrr file which may be used to manipulate your processor's
1485 MTRRs. Typically the X server should use this.
1487 This code has a reasonably generic interface so that similar
1488 control registers on other processors can be easily supported
1491 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1492 Registers (ARRs) which provide a similar functionality to MTRRs. For
1493 these, the ARRs are used to emulate the MTRRs.
1494 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1495 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1496 write-combining. All of these processors are supported by this code
1497 and it makes sense to say Y here if you have one of them.
1499 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1500 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1501 can lead to all sorts of problems, so it's good to say Y here.
1503 You can safely say Y even if your machine doesn't have MTRRs, you'll
1504 just add about 9 KB to your kernel.
1506 See <file:Documentation/x86/mtrr.txt> for more information.
1508 config MTRR_SANITIZER
1510 prompt "MTRR cleanup support"
1513 Convert MTRR layout from continuous to discrete, so X drivers can
1514 add writeback entries.
1516 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1517 The largest mtrr entry size for a continuous block can be set with
1522 config MTRR_SANITIZER_ENABLE_DEFAULT
1523 int "MTRR cleanup enable value (0-1)"
1526 depends on MTRR_SANITIZER
1528 Enable mtrr cleanup default value
1530 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1531 int "MTRR cleanup spare reg num (0-7)"
1534 depends on MTRR_SANITIZER
1536 mtrr cleanup spare entries default, it can be changed via
1537 mtrr_spare_reg_nr=N on the kernel command line.
1541 prompt "x86 PAT support" if EXPERT
1544 Use PAT attributes to setup page level cache control.
1546 PATs are the modern equivalents of MTRRs and are much more
1547 flexible than MTRRs.
1549 Say N here if you see bootup problems (boot crash, boot hang,
1550 spontaneous reboots) or a non-working video driver.
1554 config ARCH_USES_PG_UNCACHED
1560 prompt "x86 architectural random number generator" if EXPERT
1562 Enable the x86 architectural RDRAND instruction
1563 (Intel Bull Mountain technology) to generate random numbers.
1564 If supported, this is a high bandwidth, cryptographically
1565 secure hardware random number generator.
1569 prompt "Supervisor Mode Access Prevention" if EXPERT
1571 Supervisor Mode Access Prevention (SMAP) is a security
1572 feature in newer Intel processors. There is a small
1573 performance cost if this enabled and turned on; there is
1574 also a small increase in the kernel size if this is enabled.
1579 bool "EFI runtime service support"
1583 This enables the kernel to use EFI runtime services that are
1584 available (such as the EFI variable services).
1586 This option is only useful on systems that have EFI firmware.
1587 In addition, you should use the latest ELILO loader available
1588 at <http://elilo.sourceforge.net> in order to take advantage
1589 of EFI runtime services. However, even with this option, the
1590 resultant kernel should continue to boot on existing non-EFI
1594 bool "EFI stub support"
1597 This kernel feature allows a bzImage to be loaded directly
1598 by EFI firmware without the use of a bootloader.
1600 See Documentation/efi-stub.txt for more information.
1604 prompt "Enable seccomp to safely compute untrusted bytecode"
1606 This kernel feature is useful for number crunching applications
1607 that may need to compute untrusted bytecode during their
1608 execution. By using pipes or other transports made available to
1609 the process as file descriptors supporting the read/write
1610 syscalls, it's possible to isolate those applications in
1611 their own address space using seccomp. Once seccomp is
1612 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1613 and the task is only allowed to execute a few safe syscalls
1614 defined by each seccomp mode.
1616 If unsure, say Y. Only embedded should say N here.
1618 config CC_STACKPROTECTOR
1619 bool "Enable -fstack-protector buffer overflow detection"
1621 This option turns on the -fstack-protector GCC feature. This
1622 feature puts, at the beginning of functions, a canary value on
1623 the stack just before the return address, and validates
1624 the value just before actually returning. Stack based buffer
1625 overflows (that need to overwrite this return address) now also
1626 overwrite the canary, which gets detected and the attack is then
1627 neutralized via a kernel panic.
1629 This feature requires gcc version 4.2 or above, or a distribution
1630 gcc with the feature backported. Older versions are automatically
1631 detected and for those versions, this configuration option is
1632 ignored. (and a warning is printed during bootup)
1634 source kernel/Kconfig.hz
1637 bool "kexec system call"
1639 kexec is a system call that implements the ability to shutdown your
1640 current kernel, and to start another kernel. It is like a reboot
1641 but it is independent of the system firmware. And like a reboot
1642 you can start any kernel with it, not just Linux.
1644 The name comes from the similarity to the exec system call.
1646 It is an ongoing process to be certain the hardware in a machine
1647 is properly shutdown, so do not be surprised if this code does not
1648 initially work for you. As of this writing the exact hardware
1649 interface is strongly in flux, so no good recommendation can be
1653 bool "kernel crash dumps"
1654 depends on X86_64 || (X86_32 && HIGHMEM)
1656 Generate crash dump after being started by kexec.
1657 This should be normally only set in special crash dump kernels
1658 which are loaded in the main kernel with kexec-tools into
1659 a specially reserved region and then later executed after
1660 a crash by kdump/kexec. The crash dump kernel must be compiled
1661 to a memory address not used by the main kernel or BIOS using
1662 PHYSICAL_START, or it must be built as a relocatable image
1663 (CONFIG_RELOCATABLE=y).
1664 For more details see Documentation/kdump/kdump.txt
1668 depends on KEXEC && HIBERNATION
1670 Jump between original kernel and kexeced kernel and invoke
1671 code in physical address mode via KEXEC
1673 config PHYSICAL_START
1674 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1677 This gives the physical address where the kernel is loaded.
1679 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1680 bzImage will decompress itself to above physical address and
1681 run from there. Otherwise, bzImage will run from the address where
1682 it has been loaded by the boot loader and will ignore above physical
1685 In normal kdump cases one does not have to set/change this option
1686 as now bzImage can be compiled as a completely relocatable image
1687 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1688 address. This option is mainly useful for the folks who don't want
1689 to use a bzImage for capturing the crash dump and want to use a
1690 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1691 to be specifically compiled to run from a specific memory area
1692 (normally a reserved region) and this option comes handy.
1694 So if you are using bzImage for capturing the crash dump,
1695 leave the value here unchanged to 0x1000000 and set
1696 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1697 for capturing the crash dump change this value to start of
1698 the reserved region. In other words, it can be set based on
1699 the "X" value as specified in the "crashkernel=YM@XM"
1700 command line boot parameter passed to the panic-ed
1701 kernel. Please take a look at Documentation/kdump/kdump.txt
1702 for more details about crash dumps.
1704 Usage of bzImage for capturing the crash dump is recommended as
1705 one does not have to build two kernels. Same kernel can be used
1706 as production kernel and capture kernel. Above option should have
1707 gone away after relocatable bzImage support is introduced. But it
1708 is present because there are users out there who continue to use
1709 vmlinux for dump capture. This option should go away down the
1712 Don't change this unless you know what you are doing.
1715 bool "Build a relocatable kernel"
1718 This builds a kernel image that retains relocation information
1719 so it can be loaded someplace besides the default 1MB.
1720 The relocations tend to make the kernel binary about 10% larger,
1721 but are discarded at runtime.
1723 One use is for the kexec on panic case where the recovery kernel
1724 must live at a different physical address than the primary
1727 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1728 it has been loaded at and the compile time physical address
1729 (CONFIG_PHYSICAL_START) is used as the minimum location.
1731 config RANDOMIZE_BASE
1732 bool "Randomize the address of the kernel image"
1733 depends on RELOCATABLE
1734 depends on !HIBERNATION
1737 Randomizes the physical and virtual address at which the
1738 kernel image is decompressed, as a security feature that
1739 deters exploit attempts relying on knowledge of the location
1740 of kernel internals.
1742 Entropy is generated using the RDRAND instruction if it
1743 is supported. If not, then RDTSC is used, if supported. If
1744 neither RDRAND nor RDTSC are supported, then no randomness
1747 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1748 and aligned according to PHYSICAL_ALIGN.
1750 config RANDOMIZE_BASE_MAX_OFFSET
1751 hex "Maximum ASLR offset allowed"
1752 depends on RANDOMIZE_BASE
1753 range 0x0 0x20000000 if X86_32
1754 default "0x20000000" if X86_32
1755 range 0x0 0x40000000 if X86_64
1756 default "0x40000000" if X86_64
1758 Determines the maximal offset in bytes that will be applied to the
1759 kernel when Address Space Layout Randomization (ASLR) is active.
1760 Must be less than or equal to the actual physical memory on the
1761 system. This must be a multiple of CONFIG_PHYSICAL_ALIGN.
1763 On 32-bit this is limited to 512MiB.
1765 On 64-bit this is limited by how the kernel fixmap page table is
1766 positioned, so this cannot be larger that 1GiB currently. Normally
1767 there is a 512MiB to 1.5GiB split between kernel and modules. When
1768 this is raised above the 512MiB default, the modules area will
1769 shrink to compensate, up to the current maximum 1GiB to 1GiB split.
1771 # Relocation on x86 needs some additional build support
1772 config X86_NEED_RELOCS
1774 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1776 config PHYSICAL_ALIGN
1777 hex "Alignment value to which kernel should be aligned"
1779 range 0x2000 0x1000000 if X86_32
1780 range 0x200000 0x1000000 if X86_64
1782 This value puts the alignment restrictions on physical address
1783 where kernel is loaded and run from. Kernel is compiled for an
1784 address which meets above alignment restriction.
1786 If bootloader loads the kernel at a non-aligned address and
1787 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1788 address aligned to above value and run from there.
1790 If bootloader loads the kernel at a non-aligned address and
1791 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1792 load address and decompress itself to the address it has been
1793 compiled for and run from there. The address for which kernel is
1794 compiled already meets above alignment restrictions. Hence the
1795 end result is that kernel runs from a physical address meeting
1796 above alignment restrictions.
1798 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1799 this value must be a multiple of 0x200000.
1801 Don't change this unless you know what you are doing.
1804 bool "Support for hot-pluggable CPUs"
1807 Say Y here to allow turning CPUs off and on. CPUs can be
1808 controlled through /sys/devices/system/cpu.
1809 ( Note: power management support will enable this option
1810 automatically on SMP systems. )
1811 Say N if you want to disable CPU hotplug.
1813 config BOOTPARAM_HOTPLUG_CPU0
1814 bool "Set default setting of cpu0_hotpluggable"
1816 depends on HOTPLUG_CPU
1818 Set whether default state of cpu0_hotpluggable is on or off.
1820 Say Y here to enable CPU0 hotplug by default. If this switch
1821 is turned on, there is no need to give cpu0_hotplug kernel
1822 parameter and the CPU0 hotplug feature is enabled by default.
1824 Please note: there are two known CPU0 dependencies if you want
1825 to enable the CPU0 hotplug feature either by this switch or by
1826 cpu0_hotplug kernel parameter.
1828 First, resume from hibernate or suspend always starts from CPU0.
1829 So hibernate and suspend are prevented if CPU0 is offline.
1831 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1832 offline if any interrupt can not migrate out of CPU0. There may
1833 be other CPU0 dependencies.
1835 Please make sure the dependencies are under your control before
1836 you enable this feature.
1838 Say N if you don't want to enable CPU0 hotplug feature by default.
1839 You still can enable the CPU0 hotplug feature at boot by kernel
1840 parameter cpu0_hotplug.
1842 config DEBUG_HOTPLUG_CPU0
1844 prompt "Debug CPU0 hotplug"
1845 depends on HOTPLUG_CPU
1847 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1848 soon as possible and boots up userspace with CPU0 offlined. User
1849 can online CPU0 back after boot time.
1851 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1852 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1853 compilation or giving cpu0_hotplug kernel parameter at boot.
1859 prompt "Compat VDSO support"
1860 depends on X86_32 || IA32_EMULATION
1862 Map the 32-bit VDSO to the predictable old-style address too.
1864 Say N here if you are running a sufficiently recent glibc
1865 version (2.3.3 or later), to remove the high-mapped
1866 VDSO mapping and to exclusively use the randomized VDSO.
1871 bool "Built-in kernel command line"
1873 Allow for specifying boot arguments to the kernel at
1874 build time. On some systems (e.g. embedded ones), it is
1875 necessary or convenient to provide some or all of the
1876 kernel boot arguments with the kernel itself (that is,
1877 to not rely on the boot loader to provide them.)
1879 To compile command line arguments into the kernel,
1880 set this option to 'Y', then fill in the
1881 the boot arguments in CONFIG_CMDLINE.
1883 Systems with fully functional boot loaders (i.e. non-embedded)
1884 should leave this option set to 'N'.
1887 string "Built-in kernel command string"
1888 depends on CMDLINE_BOOL
1891 Enter arguments here that should be compiled into the kernel
1892 image and used at boot time. If the boot loader provides a
1893 command line at boot time, it is appended to this string to
1894 form the full kernel command line, when the system boots.
1896 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1897 change this behavior.
1899 In most cases, the command line (whether built-in or provided
1900 by the boot loader) should specify the device for the root
1903 config CMDLINE_OVERRIDE
1904 bool "Built-in command line overrides boot loader arguments"
1905 depends on CMDLINE_BOOL
1907 Set this option to 'Y' to have the kernel ignore the boot loader
1908 command line, and use ONLY the built-in command line.
1910 This is used to work around broken boot loaders. This should
1911 be set to 'N' under normal conditions.
1915 config ARCH_ENABLE_MEMORY_HOTPLUG
1917 depends on X86_64 || (X86_32 && HIGHMEM)
1919 config ARCH_ENABLE_MEMORY_HOTREMOVE
1921 depends on MEMORY_HOTPLUG
1923 config USE_PERCPU_NUMA_NODE_ID
1927 menu "Power management and ACPI options"
1929 config ARCH_HIBERNATION_HEADER
1931 depends on X86_64 && HIBERNATION
1933 source "kernel/power/Kconfig"
1935 source "drivers/acpi/Kconfig"
1937 source "drivers/sfi/Kconfig"
1944 tristate "APM (Advanced Power Management) BIOS support"
1945 depends on X86_32 && PM_SLEEP
1947 APM is a BIOS specification for saving power using several different
1948 techniques. This is mostly useful for battery powered laptops with
1949 APM compliant BIOSes. If you say Y here, the system time will be
1950 reset after a RESUME operation, the /proc/apm device will provide
1951 battery status information, and user-space programs will receive
1952 notification of APM "events" (e.g. battery status change).
1954 If you select "Y" here, you can disable actual use of the APM
1955 BIOS by passing the "apm=off" option to the kernel at boot time.
1957 Note that the APM support is almost completely disabled for
1958 machines with more than one CPU.
1960 In order to use APM, you will need supporting software. For location
1961 and more information, read <file:Documentation/power/apm-acpi.txt>
1962 and the Battery Powered Linux mini-HOWTO, available from
1963 <http://www.tldp.org/docs.html#howto>.
1965 This driver does not spin down disk drives (see the hdparm(8)
1966 manpage ("man 8 hdparm") for that), and it doesn't turn off
1967 VESA-compliant "green" monitors.
1969 This driver does not support the TI 4000M TravelMate and the ACER
1970 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1971 desktop machines also don't have compliant BIOSes, and this driver
1972 may cause those machines to panic during the boot phase.
1974 Generally, if you don't have a battery in your machine, there isn't
1975 much point in using this driver and you should say N. If you get
1976 random kernel OOPSes or reboots that don't seem to be related to
1977 anything, try disabling/enabling this option (or disabling/enabling
1980 Some other things you should try when experiencing seemingly random,
1983 1) make sure that you have enough swap space and that it is
1985 2) pass the "no-hlt" option to the kernel
1986 3) switch on floating point emulation in the kernel and pass
1987 the "no387" option to the kernel
1988 4) pass the "floppy=nodma" option to the kernel
1989 5) pass the "mem=4M" option to the kernel (thereby disabling
1990 all but the first 4 MB of RAM)
1991 6) make sure that the CPU is not over clocked.
1992 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1993 8) disable the cache from your BIOS settings
1994 9) install a fan for the video card or exchange video RAM
1995 10) install a better fan for the CPU
1996 11) exchange RAM chips
1997 12) exchange the motherboard.
1999 To compile this driver as a module, choose M here: the
2000 module will be called apm.
2004 config APM_IGNORE_USER_SUSPEND
2005 bool "Ignore USER SUSPEND"
2007 This option will ignore USER SUSPEND requests. On machines with a
2008 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2009 series notebooks, it is necessary to say Y because of a BIOS bug.
2011 config APM_DO_ENABLE
2012 bool "Enable PM at boot time"
2014 Enable APM features at boot time. From page 36 of the APM BIOS
2015 specification: "When disabled, the APM BIOS does not automatically
2016 power manage devices, enter the Standby State, enter the Suspend
2017 State, or take power saving steps in response to CPU Idle calls."
2018 This driver will make CPU Idle calls when Linux is idle (unless this
2019 feature is turned off -- see "Do CPU IDLE calls", below). This
2020 should always save battery power, but more complicated APM features
2021 will be dependent on your BIOS implementation. You may need to turn
2022 this option off if your computer hangs at boot time when using APM
2023 support, or if it beeps continuously instead of suspending. Turn
2024 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2025 T400CDT. This is off by default since most machines do fine without
2030 bool "Make CPU Idle calls when idle"
2032 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2033 On some machines, this can activate improved power savings, such as
2034 a slowed CPU clock rate, when the machine is idle. These idle calls
2035 are made after the idle loop has run for some length of time (e.g.,
2036 333 mS). On some machines, this will cause a hang at boot time or
2037 whenever the CPU becomes idle. (On machines with more than one CPU,
2038 this option does nothing.)
2040 config APM_DISPLAY_BLANK
2041 bool "Enable console blanking using APM"
2043 Enable console blanking using the APM. Some laptops can use this to
2044 turn off the LCD backlight when the screen blanker of the Linux
2045 virtual console blanks the screen. Note that this is only used by
2046 the virtual console screen blanker, and won't turn off the backlight
2047 when using the X Window system. This also doesn't have anything to
2048 do with your VESA-compliant power-saving monitor. Further, this
2049 option doesn't work for all laptops -- it might not turn off your
2050 backlight at all, or it might print a lot of errors to the console,
2051 especially if you are using gpm.
2053 config APM_ALLOW_INTS
2054 bool "Allow interrupts during APM BIOS calls"
2056 Normally we disable external interrupts while we are making calls to
2057 the APM BIOS as a measure to lessen the effects of a badly behaving
2058 BIOS implementation. The BIOS should reenable interrupts if it
2059 needs to. Unfortunately, some BIOSes do not -- especially those in
2060 many of the newer IBM Thinkpads. If you experience hangs when you
2061 suspend, try setting this to Y. Otherwise, say N.
2065 source "drivers/cpufreq/Kconfig"
2067 source "drivers/cpuidle/Kconfig"
2069 source "drivers/idle/Kconfig"
2074 menu "Bus options (PCI etc.)"
2080 Find out whether you have a PCI motherboard. PCI is the name of a
2081 bus system, i.e. the way the CPU talks to the other stuff inside
2082 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2083 VESA. If you have PCI, say Y, otherwise N.
2086 prompt "PCI access mode"
2087 depends on X86_32 && PCI
2090 On PCI systems, the BIOS can be used to detect the PCI devices and
2091 determine their configuration. However, some old PCI motherboards
2092 have BIOS bugs and may crash if this is done. Also, some embedded
2093 PCI-based systems don't have any BIOS at all. Linux can also try to
2094 detect the PCI hardware directly without using the BIOS.
2096 With this option, you can specify how Linux should detect the
2097 PCI devices. If you choose "BIOS", the BIOS will be used,
2098 if you choose "Direct", the BIOS won't be used, and if you
2099 choose "MMConfig", then PCI Express MMCONFIG will be used.
2100 If you choose "Any", the kernel will try MMCONFIG, then the
2101 direct access method and falls back to the BIOS if that doesn't
2102 work. If unsure, go with the default, which is "Any".
2107 config PCI_GOMMCONFIG
2124 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2126 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2129 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2133 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2137 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2141 depends on PCI && XEN
2149 bool "Support mmconfig PCI config space access"
2150 depends on X86_64 && PCI && ACPI
2152 config PCI_CNB20LE_QUIRK
2153 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2156 Read the PCI windows out of the CNB20LE host bridge. This allows
2157 PCI hotplug to work on systems with the CNB20LE chipset which do
2160 There's no public spec for this chipset, and this functionality
2161 is known to be incomplete.
2163 You should say N unless you know you need this.
2165 source "drivers/pci/pcie/Kconfig"
2167 source "drivers/pci/Kconfig"
2169 # x86_64 have no ISA slots, but can have ISA-style DMA.
2171 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2174 Enables ISA-style DMA support for devices requiring such controllers.
2182 Find out whether you have ISA slots on your motherboard. ISA is the
2183 name of a bus system, i.e. the way the CPU talks to the other stuff
2184 inside your box. Other bus systems are PCI, EISA, MicroChannel
2185 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2186 newer boards don't support it. If you have ISA, say Y, otherwise N.
2192 The Extended Industry Standard Architecture (EISA) bus was
2193 developed as an open alternative to the IBM MicroChannel bus.
2195 The EISA bus provided some of the features of the IBM MicroChannel
2196 bus while maintaining backward compatibility with cards made for
2197 the older ISA bus. The EISA bus saw limited use between 1988 and
2198 1995 when it was made obsolete by the PCI bus.
2200 Say Y here if you are building a kernel for an EISA-based machine.
2204 source "drivers/eisa/Kconfig"
2207 tristate "NatSemi SCx200 support"
2209 This provides basic support for National Semiconductor's
2210 (now AMD's) Geode processors. The driver probes for the
2211 PCI-IDs of several on-chip devices, so its a good dependency
2212 for other scx200_* drivers.
2214 If compiled as a module, the driver is named scx200.
2216 config SCx200HR_TIMER
2217 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2221 This driver provides a clocksource built upon the on-chip
2222 27MHz high-resolution timer. Its also a workaround for
2223 NSC Geode SC-1100's buggy TSC, which loses time when the
2224 processor goes idle (as is done by the scheduler). The
2225 other workaround is idle=poll boot option.
2228 bool "One Laptop Per Child support"
2235 Add support for detecting the unique features of the OLPC
2239 bool "OLPC XO-1 Power Management"
2240 depends on OLPC && MFD_CS5535 && PM_SLEEP
2243 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2246 bool "OLPC XO-1 Real Time Clock"
2247 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2249 Add support for the XO-1 real time clock, which can be used as a
2250 programmable wakeup source.
2253 bool "OLPC XO-1 SCI extras"
2254 depends on OLPC && OLPC_XO1_PM
2260 Add support for SCI-based features of the OLPC XO-1 laptop:
2261 - EC-driven system wakeups
2265 - AC adapter status updates
2266 - Battery status updates
2268 config OLPC_XO15_SCI
2269 bool "OLPC XO-1.5 SCI extras"
2270 depends on OLPC && ACPI
2273 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2274 - EC-driven system wakeups
2275 - AC adapter status updates
2276 - Battery status updates
2279 bool "PCEngines ALIX System Support (LED setup)"
2282 This option enables system support for the PCEngines ALIX.
2283 At present this just sets up LEDs for GPIO control on
2284 ALIX2/3/6 boards. However, other system specific setup should
2287 Note: You must still enable the drivers for GPIO and LED support
2288 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2290 Note: You have to set alix.force=1 for boards with Award BIOS.
2293 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2296 This option enables system support for the Soekris Engineering net5501.
2299 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2303 This option enables system support for the Traverse Technologies GEOS.
2306 bool "Technologic Systems TS-5500 platform support"
2308 select CHECK_SIGNATURE
2312 This option enables system support for the Technologic Systems TS-5500.
2318 depends on CPU_SUP_AMD && PCI
2320 source "drivers/pcmcia/Kconfig"
2322 source "drivers/pci/hotplug/Kconfig"
2325 tristate "RapidIO support"
2329 If enabled this option will include drivers and the core
2330 infrastructure code to support RapidIO interconnect devices.
2332 source "drivers/rapidio/Kconfig"
2335 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2337 Firmwares often provide initial graphics framebuffers so the BIOS,
2338 bootloader or kernel can show basic video-output during boot for
2339 user-guidance and debugging. Historically, x86 used the VESA BIOS
2340 Extensions and EFI-framebuffers for this, which are mostly limited
2342 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2343 framebuffers so the new generic system-framebuffer drivers can be
2344 used on x86. If the framebuffer is not compatible with the generic
2345 modes, it is adverticed as fallback platform framebuffer so legacy
2346 drivers like efifb, vesafb and uvesafb can pick it up.
2347 If this option is not selected, all system framebuffers are always
2348 marked as fallback platform framebuffers as usual.
2350 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2351 not be able to pick up generic system framebuffers if this option
2352 is selected. You are highly encouraged to enable simplefb as
2353 replacement if you select this option. simplefb can correctly deal
2354 with generic system framebuffers. But you should still keep vesafb
2355 and others enabled as fallback if a system framebuffer is
2356 incompatible with simplefb.
2363 menu "Executable file formats / Emulations"
2365 source "fs/Kconfig.binfmt"
2367 config IA32_EMULATION
2368 bool "IA32 Emulation"
2371 select COMPAT_BINFMT_ELF
2374 Include code to run legacy 32-bit programs under a
2375 64-bit kernel. You should likely turn this on, unless you're
2376 100% sure that you don't have any 32-bit programs left.
2379 tristate "IA32 a.out support"
2380 depends on IA32_EMULATION
2382 Support old a.out binaries in the 32bit emulation.
2385 bool "x32 ABI for 64-bit mode"
2386 depends on X86_64 && IA32_EMULATION
2388 Include code to run binaries for the x32 native 32-bit ABI
2389 for 64-bit processors. An x32 process gets access to the
2390 full 64-bit register file and wide data path while leaving
2391 pointers at 32 bits for smaller memory footprint.
2393 You will need a recent binutils (2.22 or later) with
2394 elf32_x86_64 support enabled to compile a kernel with this
2399 depends on IA32_EMULATION || X86_X32
2400 select ARCH_WANT_OLD_COMPAT_IPC
2403 config COMPAT_FOR_U64_ALIGNMENT
2406 config SYSVIPC_COMPAT
2418 config HAVE_ATOMIC_IOMAP
2422 config X86_DEV_DMA_OPS
2424 depends on X86_64 || STA2X11
2426 config X86_DMA_REMAP
2430 source "net/Kconfig"
2432 source "drivers/Kconfig"
2434 source "drivers/firmware/Kconfig"
2438 source "arch/x86/Kconfig.debug"
2440 source "security/Kconfig"
2442 source "crypto/Kconfig"
2444 source "arch/x86/kvm/Kconfig"
2446 source "lib/Kconfig"
projects / karo-tx-linux.git / blob