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 HAVE_AOUT if X86_32
26 select HAVE_UNSTABLE_SCHED_CLOCK
27 select ARCH_SUPPORTS_NUMA_BALANCING
28 select ARCH_WANTS_PROT_NUMA_PROT_NONE
31 select HAVE_PCSPKR_PLATFORM
32 select HAVE_PERF_EVENTS
33 select HAVE_IOREMAP_PROT
36 select HAVE_MEMBLOCK_NODE_MAP
37 select ARCH_DISCARD_MEMBLOCK
38 select ARCH_WANT_OPTIONAL_GPIOLIB
39 select ARCH_WANT_FRAME_POINTERS
41 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
42 select HAVE_KRETPROBES
44 select HAVE_KPROBES_ON_FTRACE
45 select HAVE_FTRACE_MCOUNT_RECORD
46 select HAVE_FENTRY if X86_64
47 select HAVE_C_RECORDMCOUNT
48 select HAVE_DYNAMIC_FTRACE
49 select HAVE_DYNAMIC_FTRACE_WITH_REGS
50 select HAVE_FUNCTION_TRACER
51 select HAVE_FUNCTION_GRAPH_TRACER
52 select HAVE_FUNCTION_GRAPH_FP_TEST
53 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
54 select HAVE_SYSCALL_TRACEPOINTS
55 select SYSCTL_EXCEPTION_TRACE
58 select HAVE_ARCH_TRACEHOOK
59 select HAVE_GENERIC_DMA_COHERENT if X86_32
60 select HAVE_EFFICIENT_UNALIGNED_ACCESS
61 select USER_STACKTRACE_SUPPORT
62 select HAVE_REGS_AND_STACK_ACCESS_API
63 select HAVE_DMA_API_DEBUG
64 select HAVE_KERNEL_GZIP
65 select HAVE_KERNEL_BZIP2
66 select HAVE_KERNEL_LZMA
68 select HAVE_KERNEL_LZO
69 select HAVE_KERNEL_LZ4
70 select HAVE_HW_BREAKPOINT
71 select HAVE_MIXED_BREAKPOINTS_REGS
73 select HAVE_PERF_EVENTS_NMI
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_DEBUG_KMEMLEAK
78 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
79 select HAVE_CMPXCHG_LOCAL
80 select HAVE_CMPXCHG_DOUBLE
81 select HAVE_ARCH_KMEMCHECK
82 select HAVE_USER_RETURN_NOTIFIER
83 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
84 select HAVE_ARCH_JUMP_LABEL
85 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
87 select GENERIC_FIND_FIRST_BIT
88 select GENERIC_IRQ_PROBE
89 select GENERIC_PENDING_IRQ if SMP
90 select GENERIC_IRQ_SHOW
91 select GENERIC_CLOCKEVENTS_MIN_ADJUST
92 select IRQ_FORCED_THREADING
93 select USE_GENERIC_SMP_HELPERS if SMP
94 select HAVE_BPF_JIT if X86_64
95 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
97 select ARCH_HAVE_NMI_SAFE_CMPXCHG
99 select DCACHE_WORD_ACCESS
100 select GENERIC_SMP_IDLE_THREAD
101 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
102 select HAVE_ARCH_SECCOMP_FILTER
103 select BUILDTIME_EXTABLE_SORT
104 select GENERIC_CMOS_UPDATE
105 select HAVE_ARCH_SOFT_DIRTY
106 select CLOCKSOURCE_WATCHDOG
107 select GENERIC_CLOCKEVENTS
108 select ARCH_CLOCKSOURCE_DATA if X86_64
109 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
110 select GENERIC_TIME_VSYSCALL if X86_64
111 select KTIME_SCALAR if X86_32
112 select GENERIC_STRNCPY_FROM_USER
113 select GENERIC_STRNLEN_USER
114 select HAVE_CONTEXT_TRACKING if X86_64
115 select HAVE_IRQ_TIME_ACCOUNTING
117 select MODULES_USE_ELF_REL if X86_32
118 select MODULES_USE_ELF_RELA if X86_64
119 select CLONE_BACKWARDS if X86_32
120 select ARCH_USE_BUILTIN_BSWAP
121 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
122 select OLD_SIGACTION if X86_32
123 select COMPAT_OLD_SIGACTION if IA32_EMULATION
125 select HAVE_DEBUG_STACKOVERFLOW
126 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
128 config INSTRUCTION_DECODER
130 depends on KPROBES || PERF_EVENTS || UPROBES
134 default "elf32-i386" if X86_32
135 default "elf64-x86-64" if X86_64
137 config ARCH_DEFCONFIG
139 default "arch/x86/configs/i386_defconfig" if X86_32
140 default "arch/x86/configs/x86_64_defconfig" if X86_64
142 config LOCKDEP_SUPPORT
145 config STACKTRACE_SUPPORT
148 config HAVE_LATENCYTOP_SUPPORT
157 config NEED_DMA_MAP_STATE
159 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
161 config NEED_SG_DMA_LENGTH
164 config GENERIC_ISA_DMA
166 depends on ISA_DMA_API
171 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
173 config GENERIC_BUG_RELATIVE_POINTERS
176 config GENERIC_HWEIGHT
179 config ARCH_MAY_HAVE_PC_FDC
181 depends on ISA_DMA_API
183 config RWSEM_XCHGADD_ALGORITHM
186 config GENERIC_CALIBRATE_DELAY
189 config ARCH_HAS_CPU_RELAX
192 config ARCH_HAS_CACHE_LINE_SIZE
195 config ARCH_HAS_CPU_AUTOPROBE
198 config HAVE_SETUP_PER_CPU_AREA
201 config NEED_PER_CPU_EMBED_FIRST_CHUNK
204 config NEED_PER_CPU_PAGE_FIRST_CHUNK
207 config ARCH_HIBERNATION_POSSIBLE
210 config ARCH_SUSPEND_POSSIBLE
213 config ARCH_WANT_HUGE_PMD_SHARE
216 config ARCH_WANT_GENERAL_HUGETLB
227 config ARCH_SUPPORTS_OPTIMIZED_INLINING
230 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
233 config HAVE_INTEL_TXT
235 depends on INTEL_IOMMU && ACPI
239 depends on X86_32 && SMP
243 depends on X86_64 && SMP
249 config X86_32_LAZY_GS
251 depends on X86_32 && !CC_STACKPROTECTOR
253 config ARCH_HWEIGHT_CFLAGS
255 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
256 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
258 config ARCH_CPU_PROBE_RELEASE
260 depends on HOTPLUG_CPU
262 config ARCH_SUPPORTS_UPROBES
265 source "init/Kconfig"
266 source "kernel/Kconfig.freezer"
268 menu "Processor type and features"
271 bool "DMA memory allocation support" if EXPERT
274 DMA memory allocation support allows devices with less than 32-bit
275 addressing to allocate within the first 16MB of address space.
276 Disable if no such devices will be used.
281 bool "Symmetric multi-processing support"
283 This enables support for systems with more than one CPU. If you have
284 a system with only one CPU, like most personal computers, say N. If
285 you have a system with more than one CPU, say Y.
287 If you say N here, the kernel will run on single and multiprocessor
288 machines, but will use only one CPU of a multiprocessor machine. If
289 you say Y here, the kernel will run on many, but not all,
290 singleprocessor machines. On a singleprocessor machine, the kernel
291 will run faster if you say N here.
293 Note that if you say Y here and choose architecture "586" or
294 "Pentium" under "Processor family", the kernel will not work on 486
295 architectures. Similarly, multiprocessor kernels for the "PPro"
296 architecture may not work on all Pentium based boards.
298 People using multiprocessor machines who say Y here should also say
299 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
300 Management" code will be disabled if you say Y here.
302 See also <file:Documentation/x86/i386/IO-APIC.txt>,
303 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
304 <http://www.tldp.org/docs.html#howto>.
306 If you don't know what to do here, say N.
309 bool "Support x2apic"
310 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
312 This enables x2apic support on CPUs that have this feature.
314 This allows 32-bit apic IDs (so it can support very large systems),
315 and accesses the local apic via MSRs not via mmio.
317 If you don't know what to do here, say N.
320 bool "Enable MPS table" if ACPI || SFI
322 depends on X86_LOCAL_APIC
324 For old smp systems that do not have proper acpi support. Newer systems
325 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
328 bool "Support for big SMP systems with more than 8 CPUs"
329 depends on X86_32 && SMP
331 This option is needed for the systems that have more than 8 CPUs
335 depends on X86_GOLDFISH
338 config X86_EXTENDED_PLATFORM
339 bool "Support for extended (non-PC) x86 platforms"
342 If you disable this option then the kernel will only support
343 standard PC platforms. (which covers the vast majority of
346 If you enable this option then you'll be able to select support
347 for the following (non-PC) 32 bit x86 platforms:
348 Goldfish (Android emulator)
352 SGI 320/540 (Visual Workstation)
353 STA2X11-based (e.g. Northville)
354 Summit/EXA (IBM x440)
355 Unisys ES7000 IA32 series
356 Moorestown MID devices
358 If you have one of these systems, or if you want to build a
359 generic distribution kernel, say Y here - otherwise say N.
363 config X86_EXTENDED_PLATFORM
364 bool "Support for extended (non-PC) x86 platforms"
367 If you disable this option then the kernel will only support
368 standard PC platforms. (which covers the vast majority of
371 If you enable this option then you'll be able to select support
372 for the following (non-PC) 64 bit x86 platforms:
377 If you have one of these systems, or if you want to build a
378 generic distribution kernel, say Y here - otherwise say N.
380 # This is an alphabetically sorted list of 64 bit extended platforms
381 # Please maintain the alphabetic order if and when there are additions
383 bool "Numascale NumaChip"
385 depends on X86_EXTENDED_PLATFORM
388 depends on X86_X2APIC
389 depends on PCI_MMCONFIG
391 Adds support for Numascale NumaChip large-SMP systems. Needed to
392 enable more than ~168 cores.
393 If you don't have one of these, you should say N here.
397 select HYPERVISOR_GUEST
399 depends on X86_64 && PCI
400 depends on X86_EXTENDED_PLATFORM
403 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
404 supposed to run on these EM64T-based machines. Only choose this option
405 if you have one of these machines.
408 bool "SGI Ultraviolet"
410 depends on X86_EXTENDED_PLATFORM
412 depends on X86_X2APIC
414 This option is needed in order to support SGI Ultraviolet systems.
415 If you don't have one of these, you should say N here.
417 # Following is an alphabetically sorted list of 32 bit extended platforms
418 # Please maintain the alphabetic order if and when there are additions
421 bool "Goldfish (Virtual Platform)"
423 depends on X86_EXTENDED_PLATFORM
425 Enable support for the Goldfish virtual platform used primarily
426 for Android development. Unless you are building for the Android
427 Goldfish emulator say N here.
430 bool "CE4100 TV platform"
432 depends on PCI_GODIRECT
434 depends on X86_EXTENDED_PLATFORM
435 select X86_REBOOTFIXUPS
437 select OF_EARLY_FLATTREE
440 Select for the Intel CE media processor (CE4100) SOC.
441 This option compiles in support for the CE4100 SOC for settop
442 boxes and media devices.
444 config X86_WANT_INTEL_MID
445 bool "Intel MID platform support"
447 depends on X86_EXTENDED_PLATFORM
449 Select to build a kernel capable of supporting Intel MID platform
450 systems which do not have the PCI legacy interfaces (Moorestown,
451 Medfield). If you are building for a PC class system say N here.
453 if X86_WANT_INTEL_MID
459 bool "Medfield MID platform"
462 depends on X86_IO_APIC
470 select X86_PLATFORM_DEVICES
471 select MFD_INTEL_MSIC
473 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
474 Internet Device(MID) platform.
475 Unlike standard x86 PCs, Medfield does not have many legacy devices
476 nor standard legacy replacement devices/features. e.g. Medfield does
477 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
481 config X86_INTEL_LPSS
482 bool "Intel Low Power Subsystem Support"
487 Select to build support for Intel Low Power Subsystem such as
488 found on Intel Lynxpoint PCH. Selecting this option enables
489 things like clock tree (common clock framework) and pincontrol
490 which are needed by the LPSS peripheral drivers.
493 bool "RDC R-321x SoC"
495 depends on X86_EXTENDED_PLATFORM
497 select X86_REBOOTFIXUPS
499 This option is needed for RDC R-321x system-on-chip, also known
501 If you don't have one of these chips, you should say N here.
503 config X86_32_NON_STANDARD
504 bool "Support non-standard 32-bit SMP architectures"
505 depends on X86_32 && SMP
506 depends on X86_EXTENDED_PLATFORM
508 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
509 STA2X11, default subarchitectures. It is intended for a generic
510 binary kernel. If you select them all, kernel will probe it
511 one by one and will fallback to default.
513 # Alphabetically sorted list of Non standard 32 bit platforms
516 bool "NUMAQ (IBM/Sequent)"
517 depends on X86_32_NON_STANDARD
522 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
523 NUMA multiquad box. This changes the way that processors are
524 bootstrapped, and uses Clustered Logical APIC addressing mode instead
525 of Flat Logical. You will need a new lynxer.elf file to flash your
526 firmware with - send email to <Martin.Bligh@us.ibm.com>.
528 config X86_SUPPORTS_MEMORY_FAILURE
530 # MCE code calls memory_failure():
532 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
533 depends on !X86_NUMAQ
534 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
535 depends on X86_64 || !SPARSEMEM
536 select ARCH_SUPPORTS_MEMORY_FAILURE
539 bool "SGI 320/540 (Visual Workstation)"
540 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
541 depends on X86_32_NON_STANDARD
543 The SGI Visual Workstation series is an IA32-based workstation
544 based on SGI systems chips with some legacy PC hardware attached.
546 Say Y here to create a kernel to run on the SGI 320 or 540.
548 A kernel compiled for the Visual Workstation will run on general
549 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
552 bool "STA2X11 Companion Chip Support"
553 depends on X86_32_NON_STANDARD && PCI
554 select X86_DEV_DMA_OPS
558 select ARCH_REQUIRE_GPIOLIB
561 This adds support for boards based on the STA2X11 IO-Hub,
562 a.k.a. "ConneXt". The chip is used in place of the standard
563 PC chipset, so all "standard" peripherals are missing. If this
564 option is selected the kernel will still be able to boot on
565 standard PC machines.
568 bool "Summit/EXA (IBM x440)"
569 depends on X86_32_NON_STANDARD
571 This option is needed for IBM systems that use the Summit/EXA chipset.
572 In particular, it is needed for the x440.
575 bool "Unisys ES7000 IA32 series"
576 depends on X86_32_NON_STANDARD && X86_BIGSMP
578 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
579 supposed to run on an IA32-based Unisys ES7000 system.
582 tristate "Eurobraille/Iris poweroff module"
585 The Iris machines from EuroBraille do not have APM or ACPI support
586 to shut themselves down properly. A special I/O sequence is
587 needed to do so, which is what this module does at
590 This is only for Iris machines from EuroBraille.
594 config SCHED_OMIT_FRAME_POINTER
596 prompt "Single-depth WCHAN output"
599 Calculate simpler /proc/<PID>/wchan values. If this option
600 is disabled then wchan values will recurse back to the
601 caller function. This provides more accurate wchan values,
602 at the expense of slightly more scheduling overhead.
604 If in doubt, say "Y".
606 menuconfig HYPERVISOR_GUEST
607 bool "Linux guest support"
609 Say Y here to enable options for running Linux under various hyper-
610 visors. This option enables basic hypervisor detection and platform
613 If you say N, all options in this submenu will be skipped and
614 disabled, and Linux guest support won't be built in.
619 bool "Enable paravirtualization code"
621 This changes the kernel so it can modify itself when it is run
622 under a hypervisor, potentially improving performance significantly
623 over full virtualization. However, when run without a hypervisor
624 the kernel is theoretically slower and slightly larger.
626 config PARAVIRT_DEBUG
627 bool "paravirt-ops debugging"
628 depends on PARAVIRT && DEBUG_KERNEL
630 Enable to debug paravirt_ops internals. Specifically, BUG if
631 a paravirt_op is missing when it is called.
633 config PARAVIRT_SPINLOCKS
634 bool "Paravirtualization layer for spinlocks"
635 depends on PARAVIRT && SMP
636 select UNINLINE_SPIN_UNLOCK
638 Paravirtualized spinlocks allow a pvops backend to replace the
639 spinlock implementation with something virtualization-friendly
640 (for example, block the virtual CPU rather than spinning).
642 Unfortunately the downside is an up to 5% performance hit on
643 native kernels, with various workloads.
645 If you are unsure how to answer this question, answer N.
647 source "arch/x86/xen/Kconfig"
650 bool "KVM Guest support (including kvmclock)"
652 select PARAVIRT_CLOCK
655 This option enables various optimizations for running under the KVM
656 hypervisor. It includes a paravirtualized clock, so that instead
657 of relying on a PIT (or probably other) emulation by the
658 underlying device model, the host provides the guest with
659 timing infrastructure such as time of day, and system time
662 bool "Enable debug information for KVM Guests in debugfs"
663 depends on KVM_GUEST && DEBUG_FS
666 This option enables collection of various statistics for KVM guest.
667 Statistics are displayed in debugfs filesystem. Enabling this option
668 may incur significant overhead.
670 source "arch/x86/lguest/Kconfig"
672 config PARAVIRT_TIME_ACCOUNTING
673 bool "Paravirtual steal time accounting"
677 Select this option to enable fine granularity task steal time
678 accounting. Time spent executing other tasks in parallel with
679 the current vCPU is discounted from the vCPU power. To account for
680 that, there can be a small performance impact.
682 If in doubt, say N here.
684 config PARAVIRT_CLOCK
687 endif #HYPERVISOR_GUEST
695 This option adds a kernel parameter 'memtest', which allows memtest
697 memtest=0, mean disabled; -- default
698 memtest=1, mean do 1 test pattern;
700 memtest=4, mean do 4 test patterns.
701 If you are unsure how to answer this question, answer N.
703 config X86_SUMMIT_NUMA
705 depends on X86_32 && NUMA && X86_32_NON_STANDARD
707 config X86_CYCLONE_TIMER
709 depends on X86_SUMMIT
711 source "arch/x86/Kconfig.cpu"
715 prompt "HPET Timer Support" if X86_32
717 Use the IA-PC HPET (High Precision Event Timer) to manage
718 time in preference to the PIT and RTC, if a HPET is
720 HPET is the next generation timer replacing legacy 8254s.
721 The HPET provides a stable time base on SMP
722 systems, unlike the TSC, but it is more expensive to access,
723 as it is off-chip. You can find the HPET spec at
724 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
726 You can safely choose Y here. However, HPET will only be
727 activated if the platform and the BIOS support this feature.
728 Otherwise the 8254 will be used for timing services.
730 Choose N to continue using the legacy 8254 timer.
732 config HPET_EMULATE_RTC
734 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
737 def_bool y if X86_INTEL_MID
738 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
740 depends on X86_INTEL_MID && SFI
742 APB timer is the replacement for 8254, HPET on X86 MID platforms.
743 The APBT provides a stable time base on SMP
744 systems, unlike the TSC, but it is more expensive to access,
745 as it is off-chip. APB timers are always running regardless of CPU
746 C states, they are used as per CPU clockevent device when possible.
748 # Mark as expert because too many people got it wrong.
749 # The code disables itself when not needed.
752 bool "Enable DMI scanning" if EXPERT
754 Enabled scanning of DMI to identify machine quirks. Say Y
755 here unless you have verified that your setup is not
756 affected by entries in the DMI blacklist. Required by PNP
760 bool "Old AMD GART IOMMU support"
762 depends on X86_64 && PCI && AMD_NB
764 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
765 GART based hardware IOMMUs.
767 The GART supports full DMA access for devices with 32-bit access
768 limitations, on systems with more than 3 GB. This is usually needed
769 for USB, sound, many IDE/SATA chipsets and some other devices.
771 Newer systems typically have a modern AMD IOMMU, supported via
772 the CONFIG_AMD_IOMMU=y config option.
774 In normal configurations this driver is only active when needed:
775 there's more than 3 GB of memory and the system contains a
776 32-bit limited device.
781 bool "IBM Calgary IOMMU support"
783 depends on X86_64 && PCI
785 Support for hardware IOMMUs in IBM's xSeries x366 and x460
786 systems. Needed to run systems with more than 3GB of memory
787 properly with 32-bit PCI devices that do not support DAC
788 (Double Address Cycle). Calgary also supports bus level
789 isolation, where all DMAs pass through the IOMMU. This
790 prevents them from going anywhere except their intended
791 destination. This catches hard-to-find kernel bugs and
792 mis-behaving drivers and devices that do not use the DMA-API
793 properly to set up their DMA buffers. The IOMMU can be
794 turned off at boot time with the iommu=off parameter.
795 Normally the kernel will make the right choice by itself.
798 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
800 prompt "Should Calgary be enabled by default?"
801 depends on CALGARY_IOMMU
803 Should Calgary be enabled by default? if you choose 'y', Calgary
804 will be used (if it exists). If you choose 'n', Calgary will not be
805 used even if it exists. If you choose 'n' and would like to use
806 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
809 # need this always selected by IOMMU for the VIA workaround
813 Support for software bounce buffers used on x86-64 systems
814 which don't have a hardware IOMMU. Using this PCI devices
815 which can only access 32-bits of memory can be used on systems
816 with more than 3 GB of memory.
821 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
824 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
825 depends on X86_64 && SMP && DEBUG_KERNEL
826 select CPUMASK_OFFSTACK
828 Enable maximum number of CPUS and NUMA Nodes for this architecture.
832 int "Maximum number of CPUs" if SMP && !MAXSMP
833 range 2 8 if SMP && X86_32 && !X86_BIGSMP
834 range 2 512 if SMP && !MAXSMP
836 default "4096" if MAXSMP
837 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
840 This allows you to specify the maximum number of CPUs which this
841 kernel will support. The maximum supported value is 512 and the
842 minimum value which makes sense is 2.
844 This is purely to save memory - each supported CPU adds
845 approximately eight kilobytes to the kernel image.
848 bool "SMT (Hyperthreading) scheduler support"
851 SMT scheduler support improves the CPU scheduler's decision making
852 when dealing with Intel Pentium 4 chips with HyperThreading at a
853 cost of slightly increased overhead in some places. If unsure say
858 prompt "Multi-core scheduler support"
861 Multi-core scheduler support improves the CPU scheduler's decision
862 making when dealing with multi-core CPU chips at a cost of slightly
863 increased overhead in some places. If unsure say N here.
865 source "kernel/Kconfig.preempt"
868 bool "Local APIC support on uniprocessors"
869 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
871 A local APIC (Advanced Programmable Interrupt Controller) is an
872 integrated interrupt controller in the CPU. If you have a single-CPU
873 system which has a processor with a local APIC, you can say Y here to
874 enable and use it. If you say Y here even though your machine doesn't
875 have a local APIC, then the kernel will still run with no slowdown at
876 all. The local APIC supports CPU-generated self-interrupts (timer,
877 performance counters), and the NMI watchdog which detects hard
881 bool "IO-APIC support on uniprocessors"
882 depends on X86_UP_APIC
884 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
885 SMP-capable replacement for PC-style interrupt controllers. Most
886 SMP systems and many recent uniprocessor systems have one.
888 If you have a single-CPU system with an IO-APIC, you can say Y here
889 to use it. If you say Y here even though your machine doesn't have
890 an IO-APIC, then the kernel will still run with no slowdown at all.
892 config X86_LOCAL_APIC
894 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
898 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
900 config X86_VISWS_APIC
902 depends on X86_32 && X86_VISWS
904 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
905 bool "Reroute for broken boot IRQs"
906 depends on X86_IO_APIC
908 This option enables a workaround that fixes a source of
909 spurious interrupts. This is recommended when threaded
910 interrupt handling is used on systems where the generation of
911 superfluous "boot interrupts" cannot be disabled.
913 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
914 entry in the chipset's IO-APIC is masked (as, e.g. the RT
915 kernel does during interrupt handling). On chipsets where this
916 boot IRQ generation cannot be disabled, this workaround keeps
917 the original IRQ line masked so that only the equivalent "boot
918 IRQ" is delivered to the CPUs. The workaround also tells the
919 kernel to set up the IRQ handler on the boot IRQ line. In this
920 way only one interrupt is delivered to the kernel. Otherwise
921 the spurious second interrupt may cause the kernel to bring
922 down (vital) interrupt lines.
924 Only affects "broken" chipsets. Interrupt sharing may be
925 increased on these systems.
928 bool "Machine Check / overheating reporting"
931 Machine Check support allows the processor to notify the
932 kernel if it detects a problem (e.g. overheating, data corruption).
933 The action the kernel takes depends on the severity of the problem,
934 ranging from warning messages to halting the machine.
938 prompt "Intel MCE features"
939 depends on X86_MCE && X86_LOCAL_APIC
941 Additional support for intel specific MCE features such as
946 prompt "AMD MCE features"
947 depends on X86_MCE && X86_LOCAL_APIC
949 Additional support for AMD specific MCE features such as
950 the DRAM Error Threshold.
952 config X86_ANCIENT_MCE
953 bool "Support for old Pentium 5 / WinChip machine checks"
954 depends on X86_32 && X86_MCE
956 Include support for machine check handling on old Pentium 5 or WinChip
957 systems. These typically need to be enabled explicitely on the command
960 config X86_MCE_THRESHOLD
961 depends on X86_MCE_AMD || X86_MCE_INTEL
964 config X86_MCE_INJECT
966 tristate "Machine check injector support"
968 Provide support for injecting machine checks for testing purposes.
969 If you don't know what a machine check is and you don't do kernel
970 QA it is safe to say n.
972 config X86_THERMAL_VECTOR
974 depends on X86_MCE_INTEL
977 bool "Enable VM86 support" if EXPERT
981 This option is required by programs like DOSEMU to run 16-bit legacy
982 code on X86 processors. It also may be needed by software like
983 XFree86 to initialize some video cards via BIOS. Disabling this
984 option saves about 6k.
987 tristate "Toshiba Laptop support"
990 This adds a driver to safely access the System Management Mode of
991 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
992 not work on models with a Phoenix BIOS. The System Management Mode
993 is used to set the BIOS and power saving options on Toshiba portables.
995 For information on utilities to make use of this driver see the
996 Toshiba Linux utilities web site at:
997 <http://www.buzzard.org.uk/toshiba/>.
999 Say Y if you intend to run this kernel on a Toshiba portable.
1003 tristate "Dell laptop support"
1006 This adds a driver to safely access the System Management Mode
1007 of the CPU on the Dell Inspiron 8000. The System Management Mode
1008 is used to read cpu temperature and cooling fan status and to
1009 control the fans on the I8K portables.
1011 This driver has been tested only on the Inspiron 8000 but it may
1012 also work with other Dell laptops. You can force loading on other
1013 models by passing the parameter `force=1' to the module. Use at
1016 For information on utilities to make use of this driver see the
1017 I8K Linux utilities web site at:
1018 <http://people.debian.org/~dz/i8k/>
1020 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1023 config X86_REBOOTFIXUPS
1024 bool "Enable X86 board specific fixups for reboot"
1027 This enables chipset and/or board specific fixups to be done
1028 in order to get reboot to work correctly. This is only needed on
1029 some combinations of hardware and BIOS. The symptom, for which
1030 this config is intended, is when reboot ends with a stalled/hung
1033 Currently, the only fixup is for the Geode machines using
1034 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1036 Say Y if you want to enable the fixup. Currently, it's safe to
1037 enable this option even if you don't need it.
1041 tristate "CPU microcode loading support"
1042 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1046 If you say Y here, you will be able to update the microcode on
1047 certain Intel and AMD processors. The Intel support is for the
1048 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1049 Xeon etc. The AMD support is for families 0x10 and later. You will
1050 obviously need the actual microcode binary data itself which is not
1051 shipped with the Linux kernel.
1053 This option selects the general module only, you need to select
1054 at least one vendor specific module as well.
1056 To compile this driver as a module, choose M here: the module
1057 will be called microcode.
1059 config MICROCODE_INTEL
1060 bool "Intel microcode loading support"
1061 depends on MICROCODE
1065 This options enables microcode patch loading support for Intel
1068 For latest news and information on obtaining all the required
1069 Intel ingredients for this driver, check:
1070 <http://www.urbanmyth.org/microcode/>.
1072 config MICROCODE_AMD
1073 bool "AMD microcode loading support"
1074 depends on MICROCODE
1077 If you select this option, microcode patch loading support for AMD
1078 processors will be enabled.
1080 config MICROCODE_OLD_INTERFACE
1082 depends on MICROCODE
1084 config MICROCODE_INTEL_LIB
1086 depends on MICROCODE_INTEL
1088 config MICROCODE_INTEL_EARLY
1091 config MICROCODE_AMD_EARLY
1094 config MICROCODE_EARLY
1095 bool "Early load microcode"
1096 depends on MICROCODE=y && BLK_DEV_INITRD
1097 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1098 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1101 This option provides functionality to read additional microcode data
1102 at the beginning of initrd image. The data tells kernel to load
1103 microcode to CPU's as early as possible. No functional change if no
1104 microcode data is glued to the initrd, therefore it's safe to say Y.
1107 tristate "/dev/cpu/*/msr - Model-specific register support"
1109 This device gives privileged processes access to the x86
1110 Model-Specific Registers (MSRs). It is a character device with
1111 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1112 MSR accesses are directed to a specific CPU on multi-processor
1116 tristate "/dev/cpu/*/cpuid - CPU information support"
1118 This device gives processes access to the x86 CPUID instruction to
1119 be executed on a specific processor. It is a character device
1120 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1124 prompt "High Memory Support"
1125 default HIGHMEM64G if X86_NUMAQ
1131 depends on !X86_NUMAQ
1133 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1134 However, the address space of 32-bit x86 processors is only 4
1135 Gigabytes large. That means that, if you have a large amount of
1136 physical memory, not all of it can be "permanently mapped" by the
1137 kernel. The physical memory that's not permanently mapped is called
1140 If you are compiling a kernel which will never run on a machine with
1141 more than 1 Gigabyte total physical RAM, answer "off" here (default
1142 choice and suitable for most users). This will result in a "3GB/1GB"
1143 split: 3GB are mapped so that each process sees a 3GB virtual memory
1144 space and the remaining part of the 4GB virtual memory space is used
1145 by the kernel to permanently map as much physical memory as
1148 If the machine has between 1 and 4 Gigabytes physical RAM, then
1151 If more than 4 Gigabytes is used then answer "64GB" here. This
1152 selection turns Intel PAE (Physical Address Extension) mode on.
1153 PAE implements 3-level paging on IA32 processors. PAE is fully
1154 supported by Linux, PAE mode is implemented on all recent Intel
1155 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1156 then the kernel will not boot on CPUs that don't support PAE!
1158 The actual amount of total physical memory will either be
1159 auto detected or can be forced by using a kernel command line option
1160 such as "mem=256M". (Try "man bootparam" or see the documentation of
1161 your boot loader (lilo or loadlin) about how to pass options to the
1162 kernel at boot time.)
1164 If unsure, say "off".
1168 depends on !X86_NUMAQ
1170 Select this if you have a 32-bit processor and between 1 and 4
1171 gigabytes of physical RAM.
1178 Select this if you have a 32-bit processor and more than 4
1179 gigabytes of physical RAM.
1184 prompt "Memory split" if EXPERT
1188 Select the desired split between kernel and user memory.
1190 If the address range available to the kernel is less than the
1191 physical memory installed, the remaining memory will be available
1192 as "high memory". Accessing high memory is a little more costly
1193 than low memory, as it needs to be mapped into the kernel first.
1194 Note that increasing the kernel address space limits the range
1195 available to user programs, making the address space there
1196 tighter. Selecting anything other than the default 3G/1G split
1197 will also likely make your kernel incompatible with binary-only
1200 If you are not absolutely sure what you are doing, leave this
1204 bool "3G/1G user/kernel split"
1205 config VMSPLIT_3G_OPT
1207 bool "3G/1G user/kernel split (for full 1G low memory)"
1209 bool "2G/2G user/kernel split"
1210 config VMSPLIT_2G_OPT
1212 bool "2G/2G user/kernel split (for full 2G low memory)"
1214 bool "1G/3G user/kernel split"
1219 default 0xB0000000 if VMSPLIT_3G_OPT
1220 default 0x80000000 if VMSPLIT_2G
1221 default 0x78000000 if VMSPLIT_2G_OPT
1222 default 0x40000000 if VMSPLIT_1G
1228 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1231 bool "PAE (Physical Address Extension) Support"
1232 depends on X86_32 && !HIGHMEM4G
1234 PAE is required for NX support, and furthermore enables
1235 larger swapspace support for non-overcommit purposes. It
1236 has the cost of more pagetable lookup overhead, and also
1237 consumes more pagetable space per process.
1239 config ARCH_PHYS_ADDR_T_64BIT
1241 depends on X86_64 || X86_PAE
1243 config ARCH_DMA_ADDR_T_64BIT
1245 depends on X86_64 || HIGHMEM64G
1247 config DIRECT_GBPAGES
1248 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1252 Allow the kernel linear mapping to use 1GB pages on CPUs that
1253 support it. This can improve the kernel's performance a tiny bit by
1254 reducing TLB pressure. If in doubt, say "Y".
1256 # Common NUMA Features
1258 bool "Numa Memory Allocation and Scheduler Support"
1260 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1261 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1263 Enable NUMA (Non Uniform Memory Access) support.
1265 The kernel will try to allocate memory used by a CPU on the
1266 local memory controller of the CPU and add some more
1267 NUMA awareness to the kernel.
1269 For 64-bit this is recommended if the system is Intel Core i7
1270 (or later), AMD Opteron, or EM64T NUMA.
1272 For 32-bit this is only needed on (rare) 32-bit-only platforms
1273 that support NUMA topologies, such as NUMAQ / Summit, or if you
1274 boot a 32-bit kernel on a 64-bit NUMA platform.
1276 Otherwise, you should say N.
1278 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1279 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1283 prompt "Old style AMD Opteron NUMA detection"
1284 depends on X86_64 && NUMA && PCI
1286 Enable AMD NUMA node topology detection. You should say Y here if
1287 you have a multi processor AMD system. This uses an old method to
1288 read the NUMA configuration directly from the builtin Northbridge
1289 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1290 which also takes priority if both are compiled in.
1292 config X86_64_ACPI_NUMA
1294 prompt "ACPI NUMA detection"
1295 depends on X86_64 && NUMA && ACPI && PCI
1298 Enable ACPI SRAT based node topology detection.
1300 # Some NUMA nodes have memory ranges that span
1301 # other nodes. Even though a pfn is valid and
1302 # between a node's start and end pfns, it may not
1303 # reside on that node. See memmap_init_zone()
1305 config NODES_SPAN_OTHER_NODES
1307 depends on X86_64_ACPI_NUMA
1310 bool "NUMA emulation"
1313 Enable NUMA emulation. A flat machine will be split
1314 into virtual nodes when booted with "numa=fake=N", where N is the
1315 number of nodes. This is only useful for debugging.
1318 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1320 default "10" if MAXSMP
1321 default "6" if X86_64
1322 default "4" if X86_NUMAQ
1324 depends on NEED_MULTIPLE_NODES
1326 Specify the maximum number of NUMA Nodes available on the target
1327 system. Increases memory reserved to accommodate various tables.
1329 config ARCH_HAVE_MEMORY_PRESENT
1331 depends on X86_32 && DISCONTIGMEM
1333 config NEED_NODE_MEMMAP_SIZE
1335 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1337 config ARCH_FLATMEM_ENABLE
1339 depends on X86_32 && !NUMA
1341 config ARCH_DISCONTIGMEM_ENABLE
1343 depends on NUMA && X86_32
1345 config ARCH_DISCONTIGMEM_DEFAULT
1347 depends on NUMA && X86_32
1349 config ARCH_SPARSEMEM_ENABLE
1351 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1352 select SPARSEMEM_STATIC if X86_32
1353 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1355 config ARCH_SPARSEMEM_DEFAULT
1359 config ARCH_SELECT_MEMORY_MODEL
1361 depends on ARCH_SPARSEMEM_ENABLE
1363 config ARCH_MEMORY_PROBE
1364 bool "Enable sysfs memory/probe interface"
1365 depends on X86_64 && MEMORY_HOTPLUG
1367 This option enables a sysfs memory/probe interface for testing.
1368 See Documentation/memory-hotplug.txt for more information.
1369 If you are unsure how to answer this question, answer N.
1371 config ARCH_PROC_KCORE_TEXT
1373 depends on X86_64 && PROC_KCORE
1375 config ILLEGAL_POINTER_VALUE
1378 default 0xdead000000000000 if X86_64
1383 bool "Allocate 3rd-level pagetables from highmem"
1386 The VM uses one page table entry for each page of physical memory.
1387 For systems with a lot of RAM, this can be wasteful of precious
1388 low memory. Setting this option will put user-space page table
1389 entries in high memory.
1391 config X86_CHECK_BIOS_CORRUPTION
1392 bool "Check for low memory corruption"
1394 Periodically check for memory corruption in low memory, which
1395 is suspected to be caused by BIOS. Even when enabled in the
1396 configuration, it is disabled at runtime. Enable it by
1397 setting "memory_corruption_check=1" on the kernel command
1398 line. By default it scans the low 64k of memory every 60
1399 seconds; see the memory_corruption_check_size and
1400 memory_corruption_check_period parameters in
1401 Documentation/kernel-parameters.txt to adjust this.
1403 When enabled with the default parameters, this option has
1404 almost no overhead, as it reserves a relatively small amount
1405 of memory and scans it infrequently. It both detects corruption
1406 and prevents it from affecting the running system.
1408 It is, however, intended as a diagnostic tool; if repeatable
1409 BIOS-originated corruption always affects the same memory,
1410 you can use memmap= to prevent the kernel from using that
1413 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1414 bool "Set the default setting of memory_corruption_check"
1415 depends on X86_CHECK_BIOS_CORRUPTION
1418 Set whether the default state of memory_corruption_check is
1421 config X86_RESERVE_LOW
1422 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1426 Specify the amount of low memory to reserve for the BIOS.
1428 The first page contains BIOS data structures that the kernel
1429 must not use, so that page must always be reserved.
1431 By default we reserve the first 64K of physical RAM, as a
1432 number of BIOSes are known to corrupt that memory range
1433 during events such as suspend/resume or monitor cable
1434 insertion, so it must not be used by the kernel.
1436 You can set this to 4 if you are absolutely sure that you
1437 trust the BIOS to get all its memory reservations and usages
1438 right. If you know your BIOS have problems beyond the
1439 default 64K area, you can set this to 640 to avoid using the
1440 entire low memory range.
1442 If you have doubts about the BIOS (e.g. suspend/resume does
1443 not work or there's kernel crashes after certain hardware
1444 hotplug events) then you might want to enable
1445 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1446 typical corruption patterns.
1448 Leave this to the default value of 64 if you are unsure.
1450 config MATH_EMULATION
1452 prompt "Math emulation" if X86_32
1454 Linux can emulate a math coprocessor (used for floating point
1455 operations) if you don't have one. 486DX and Pentium processors have
1456 a math coprocessor built in, 486SX and 386 do not, unless you added
1457 a 487DX or 387, respectively. (The messages during boot time can
1458 give you some hints here ["man dmesg"].) Everyone needs either a
1459 coprocessor or this emulation.
1461 If you don't have a math coprocessor, you need to say Y here; if you
1462 say Y here even though you have a coprocessor, the coprocessor will
1463 be used nevertheless. (This behavior can be changed with the kernel
1464 command line option "no387", which comes handy if your coprocessor
1465 is broken. Try "man bootparam" or see the documentation of your boot
1466 loader (lilo or loadlin) about how to pass options to the kernel at
1467 boot time.) This means that it is a good idea to say Y here if you
1468 intend to use this kernel on different machines.
1470 More information about the internals of the Linux math coprocessor
1471 emulation can be found in <file:arch/x86/math-emu/README>.
1473 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1474 kernel, it won't hurt.
1478 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1480 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1481 the Memory Type Range Registers (MTRRs) may be used to control
1482 processor access to memory ranges. This is most useful if you have
1483 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1484 allows bus write transfers to be combined into a larger transfer
1485 before bursting over the PCI/AGP bus. This can increase performance
1486 of image write operations 2.5 times or more. Saying Y here creates a
1487 /proc/mtrr file which may be used to manipulate your processor's
1488 MTRRs. Typically the X server should use this.
1490 This code has a reasonably generic interface so that similar
1491 control registers on other processors can be easily supported
1494 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1495 Registers (ARRs) which provide a similar functionality to MTRRs. For
1496 these, the ARRs are used to emulate the MTRRs.
1497 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1498 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1499 write-combining. All of these processors are supported by this code
1500 and it makes sense to say Y here if you have one of them.
1502 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1503 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1504 can lead to all sorts of problems, so it's good to say Y here.
1506 You can safely say Y even if your machine doesn't have MTRRs, you'll
1507 just add about 9 KB to your kernel.
1509 See <file:Documentation/x86/mtrr.txt> for more information.
1511 config MTRR_SANITIZER
1513 prompt "MTRR cleanup support"
1516 Convert MTRR layout from continuous to discrete, so X drivers can
1517 add writeback entries.
1519 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1520 The largest mtrr entry size for a continuous block can be set with
1525 config MTRR_SANITIZER_ENABLE_DEFAULT
1526 int "MTRR cleanup enable value (0-1)"
1529 depends on MTRR_SANITIZER
1531 Enable mtrr cleanup default value
1533 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1534 int "MTRR cleanup spare reg num (0-7)"
1537 depends on MTRR_SANITIZER
1539 mtrr cleanup spare entries default, it can be changed via
1540 mtrr_spare_reg_nr=N on the kernel command line.
1544 prompt "x86 PAT support" if EXPERT
1547 Use PAT attributes to setup page level cache control.
1549 PATs are the modern equivalents of MTRRs and are much more
1550 flexible than MTRRs.
1552 Say N here if you see bootup problems (boot crash, boot hang,
1553 spontaneous reboots) or a non-working video driver.
1557 config ARCH_USES_PG_UNCACHED
1563 prompt "x86 architectural random number generator" if EXPERT
1565 Enable the x86 architectural RDRAND instruction
1566 (Intel Bull Mountain technology) to generate random numbers.
1567 If supported, this is a high bandwidth, cryptographically
1568 secure hardware random number generator.
1572 prompt "Supervisor Mode Access Prevention" if EXPERT
1574 Supervisor Mode Access Prevention (SMAP) is a security
1575 feature in newer Intel processors. There is a small
1576 performance cost if this enabled and turned on; there is
1577 also a small increase in the kernel size if this is enabled.
1582 bool "EFI runtime service support"
1586 This enables the kernel to use EFI runtime services that are
1587 available (such as the EFI variable services).
1589 This option is only useful on systems that have EFI firmware.
1590 In addition, you should use the latest ELILO loader available
1591 at <http://elilo.sourceforge.net> in order to take advantage
1592 of EFI runtime services. However, even with this option, the
1593 resultant kernel should continue to boot on existing non-EFI
1597 bool "EFI stub support"
1600 This kernel feature allows a bzImage to be loaded directly
1601 by EFI firmware without the use of a bootloader.
1603 See Documentation/efi-stub.txt for more information.
1607 prompt "Enable seccomp to safely compute untrusted bytecode"
1609 This kernel feature is useful for number crunching applications
1610 that may need to compute untrusted bytecode during their
1611 execution. By using pipes or other transports made available to
1612 the process as file descriptors supporting the read/write
1613 syscalls, it's possible to isolate those applications in
1614 their own address space using seccomp. Once seccomp is
1615 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1616 and the task is only allowed to execute a few safe syscalls
1617 defined by each seccomp mode.
1619 If unsure, say Y. Only embedded should say N here.
1621 config CC_STACKPROTECTOR
1622 bool "Enable -fstack-protector buffer overflow detection"
1624 This option turns on the -fstack-protector GCC feature. This
1625 feature puts, at the beginning of functions, a canary value on
1626 the stack just before the return address, and validates
1627 the value just before actually returning. Stack based buffer
1628 overflows (that need to overwrite this return address) now also
1629 overwrite the canary, which gets detected and the attack is then
1630 neutralized via a kernel panic.
1632 This feature requires gcc version 4.2 or above, or a distribution
1633 gcc with the feature backported. Older versions are automatically
1634 detected and for those versions, this configuration option is
1635 ignored. (and a warning is printed during bootup)
1637 source kernel/Kconfig.hz
1640 bool "kexec system call"
1642 kexec is a system call that implements the ability to shutdown your
1643 current kernel, and to start another kernel. It is like a reboot
1644 but it is independent of the system firmware. And like a reboot
1645 you can start any kernel with it, not just Linux.
1647 The name comes from the similarity to the exec system call.
1649 It is an ongoing process to be certain the hardware in a machine
1650 is properly shutdown, so do not be surprised if this code does not
1651 initially work for you. As of this writing the exact hardware
1652 interface is strongly in flux, so no good recommendation can be
1656 bool "kernel crash dumps"
1657 depends on X86_64 || (X86_32 && HIGHMEM)
1659 Generate crash dump after being started by kexec.
1660 This should be normally only set in special crash dump kernels
1661 which are loaded in the main kernel with kexec-tools into
1662 a specially reserved region and then later executed after
1663 a crash by kdump/kexec. The crash dump kernel must be compiled
1664 to a memory address not used by the main kernel or BIOS using
1665 PHYSICAL_START, or it must be built as a relocatable image
1666 (CONFIG_RELOCATABLE=y).
1667 For more details see Documentation/kdump/kdump.txt
1671 depends on KEXEC && HIBERNATION
1673 Jump between original kernel and kexeced kernel and invoke
1674 code in physical address mode via KEXEC
1676 config PHYSICAL_START
1677 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1680 This gives the physical address where the kernel is loaded.
1682 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1683 bzImage will decompress itself to above physical address and
1684 run from there. Otherwise, bzImage will run from the address where
1685 it has been loaded by the boot loader and will ignore above physical
1688 In normal kdump cases one does not have to set/change this option
1689 as now bzImage can be compiled as a completely relocatable image
1690 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1691 address. This option is mainly useful for the folks who don't want
1692 to use a bzImage for capturing the crash dump and want to use a
1693 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1694 to be specifically compiled to run from a specific memory area
1695 (normally a reserved region) and this option comes handy.
1697 So if you are using bzImage for capturing the crash dump,
1698 leave the value here unchanged to 0x1000000 and set
1699 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1700 for capturing the crash dump change this value to start of
1701 the reserved region. In other words, it can be set based on
1702 the "X" value as specified in the "crashkernel=YM@XM"
1703 command line boot parameter passed to the panic-ed
1704 kernel. Please take a look at Documentation/kdump/kdump.txt
1705 for more details about crash dumps.
1707 Usage of bzImage for capturing the crash dump is recommended as
1708 one does not have to build two kernels. Same kernel can be used
1709 as production kernel and capture kernel. Above option should have
1710 gone away after relocatable bzImage support is introduced. But it
1711 is present because there are users out there who continue to use
1712 vmlinux for dump capture. This option should go away down the
1715 Don't change this unless you know what you are doing.
1718 bool "Build a relocatable kernel"
1721 This builds a kernel image that retains relocation information
1722 so it can be loaded someplace besides the default 1MB.
1723 The relocations tend to make the kernel binary about 10% larger,
1724 but are discarded at runtime.
1726 One use is for the kexec on panic case where the recovery kernel
1727 must live at a different physical address than the primary
1730 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1731 it has been loaded at and the compile time physical address
1732 (CONFIG_PHYSICAL_START) is used as the minimum location.
1734 config RANDOMIZE_BASE
1735 bool "Randomize the address of the kernel image"
1736 depends on RELOCATABLE
1737 depends on !HIBERNATION
1740 Randomizes the physical and virtual address at which the
1741 kernel image is decompressed, as a security feature that
1742 deters exploit attempts relying on knowledge of the location
1743 of kernel internals.
1745 Entropy is generated using the RDRAND instruction if it
1746 is supported. If not, then RDTSC is used, if supported. If
1747 neither RDRAND nor RDTSC are supported, then no randomness
1750 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1751 and aligned according to PHYSICAL_ALIGN.
1753 config RANDOMIZE_BASE_MAX_OFFSET
1754 hex "Maximum ASLR offset allowed"
1755 depends on RANDOMIZE_BASE
1756 range 0x0 0x20000000 if X86_32
1757 default "0x20000000" if X86_32
1758 range 0x0 0x40000000 if X86_64
1759 default "0x40000000" if X86_64
1761 Determines the maximal offset in bytes that will be applied to the
1762 kernel when Address Space Layout Randomization (ASLR) is active.
1763 Must be less than or equal to the actual physical memory on the
1764 system. This must be a multiple of CONFIG_PHYSICAL_ALIGN.
1766 On 32-bit this is limited to 512MiB.
1768 On 64-bit this is limited by how the kernel fixmap page table is
1769 positioned, so this cannot be larger that 1GiB currently. Normally
1770 there is a 512MiB to 1.5GiB split between kernel and modules. When
1771 this is raised above the 512MiB default, the modules area will
1772 shrink to compensate, up to the current maximum 1GiB to 1GiB split.
1774 # Relocation on x86 needs some additional build support
1775 config X86_NEED_RELOCS
1777 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1779 config PHYSICAL_ALIGN
1780 hex "Alignment value to which kernel should be aligned"
1782 range 0x2000 0x1000000 if X86_32
1783 range 0x200000 0x1000000 if X86_64
1785 This value puts the alignment restrictions on physical address
1786 where kernel is loaded and run from. Kernel is compiled for an
1787 address which meets above alignment restriction.
1789 If bootloader loads the kernel at a non-aligned address and
1790 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1791 address aligned to above value and run from there.
1793 If bootloader loads the kernel at a non-aligned address and
1794 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1795 load address and decompress itself to the address it has been
1796 compiled for and run from there. The address for which kernel is
1797 compiled already meets above alignment restrictions. Hence the
1798 end result is that kernel runs from a physical address meeting
1799 above alignment restrictions.
1801 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1802 this value must be a multiple of 0x200000.
1804 Don't change this unless you know what you are doing.
1807 bool "Support for hot-pluggable CPUs"
1810 Say Y here to allow turning CPUs off and on. CPUs can be
1811 controlled through /sys/devices/system/cpu.
1812 ( Note: power management support will enable this option
1813 automatically on SMP systems. )
1814 Say N if you want to disable CPU hotplug.
1816 config BOOTPARAM_HOTPLUG_CPU0
1817 bool "Set default setting of cpu0_hotpluggable"
1819 depends on HOTPLUG_CPU
1821 Set whether default state of cpu0_hotpluggable is on or off.
1823 Say Y here to enable CPU0 hotplug by default. If this switch
1824 is turned on, there is no need to give cpu0_hotplug kernel
1825 parameter and the CPU0 hotplug feature is enabled by default.
1827 Please note: there are two known CPU0 dependencies if you want
1828 to enable the CPU0 hotplug feature either by this switch or by
1829 cpu0_hotplug kernel parameter.
1831 First, resume from hibernate or suspend always starts from CPU0.
1832 So hibernate and suspend are prevented if CPU0 is offline.
1834 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1835 offline if any interrupt can not migrate out of CPU0. There may
1836 be other CPU0 dependencies.
1838 Please make sure the dependencies are under your control before
1839 you enable this feature.
1841 Say N if you don't want to enable CPU0 hotplug feature by default.
1842 You still can enable the CPU0 hotplug feature at boot by kernel
1843 parameter cpu0_hotplug.
1845 config DEBUG_HOTPLUG_CPU0
1847 prompt "Debug CPU0 hotplug"
1848 depends on HOTPLUG_CPU
1850 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1851 soon as possible and boots up userspace with CPU0 offlined. User
1852 can online CPU0 back after boot time.
1854 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1855 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1856 compilation or giving cpu0_hotplug kernel parameter at boot.
1862 prompt "Compat VDSO support"
1863 depends on X86_32 || IA32_EMULATION
1865 Map the 32-bit VDSO to the predictable old-style address too.
1867 Say N here if you are running a sufficiently recent glibc
1868 version (2.3.3 or later), to remove the high-mapped
1869 VDSO mapping and to exclusively use the randomized VDSO.
1874 bool "Built-in kernel command line"
1876 Allow for specifying boot arguments to the kernel at
1877 build time. On some systems (e.g. embedded ones), it is
1878 necessary or convenient to provide some or all of the
1879 kernel boot arguments with the kernel itself (that is,
1880 to not rely on the boot loader to provide them.)
1882 To compile command line arguments into the kernel,
1883 set this option to 'Y', then fill in the
1884 the boot arguments in CONFIG_CMDLINE.
1886 Systems with fully functional boot loaders (i.e. non-embedded)
1887 should leave this option set to 'N'.
1890 string "Built-in kernel command string"
1891 depends on CMDLINE_BOOL
1894 Enter arguments here that should be compiled into the kernel
1895 image and used at boot time. If the boot loader provides a
1896 command line at boot time, it is appended to this string to
1897 form the full kernel command line, when the system boots.
1899 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1900 change this behavior.
1902 In most cases, the command line (whether built-in or provided
1903 by the boot loader) should specify the device for the root
1906 config CMDLINE_OVERRIDE
1907 bool "Built-in command line overrides boot loader arguments"
1908 depends on CMDLINE_BOOL
1910 Set this option to 'Y' to have the kernel ignore the boot loader
1911 command line, and use ONLY the built-in command line.
1913 This is used to work around broken boot loaders. This should
1914 be set to 'N' under normal conditions.
1918 config ARCH_ENABLE_MEMORY_HOTPLUG
1920 depends on X86_64 || (X86_32 && HIGHMEM)
1922 config ARCH_ENABLE_MEMORY_HOTREMOVE
1924 depends on MEMORY_HOTPLUG
1926 config USE_PERCPU_NUMA_NODE_ID
1930 menu "Power management and ACPI options"
1932 config ARCH_HIBERNATION_HEADER
1934 depends on X86_64 && HIBERNATION
1936 source "kernel/power/Kconfig"
1938 source "drivers/acpi/Kconfig"
1940 source "drivers/sfi/Kconfig"
1947 tristate "APM (Advanced Power Management) BIOS support"
1948 depends on X86_32 && PM_SLEEP
1950 APM is a BIOS specification for saving power using several different
1951 techniques. This is mostly useful for battery powered laptops with
1952 APM compliant BIOSes. If you say Y here, the system time will be
1953 reset after a RESUME operation, the /proc/apm device will provide
1954 battery status information, and user-space programs will receive
1955 notification of APM "events" (e.g. battery status change).
1957 If you select "Y" here, you can disable actual use of the APM
1958 BIOS by passing the "apm=off" option to the kernel at boot time.
1960 Note that the APM support is almost completely disabled for
1961 machines with more than one CPU.
1963 In order to use APM, you will need supporting software. For location
1964 and more information, read <file:Documentation/power/apm-acpi.txt>
1965 and the Battery Powered Linux mini-HOWTO, available from
1966 <http://www.tldp.org/docs.html#howto>.
1968 This driver does not spin down disk drives (see the hdparm(8)
1969 manpage ("man 8 hdparm") for that), and it doesn't turn off
1970 VESA-compliant "green" monitors.
1972 This driver does not support the TI 4000M TravelMate and the ACER
1973 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1974 desktop machines also don't have compliant BIOSes, and this driver
1975 may cause those machines to panic during the boot phase.
1977 Generally, if you don't have a battery in your machine, there isn't
1978 much point in using this driver and you should say N. If you get
1979 random kernel OOPSes or reboots that don't seem to be related to
1980 anything, try disabling/enabling this option (or disabling/enabling
1983 Some other things you should try when experiencing seemingly random,
1986 1) make sure that you have enough swap space and that it is
1988 2) pass the "no-hlt" option to the kernel
1989 3) switch on floating point emulation in the kernel and pass
1990 the "no387" option to the kernel
1991 4) pass the "floppy=nodma" option to the kernel
1992 5) pass the "mem=4M" option to the kernel (thereby disabling
1993 all but the first 4 MB of RAM)
1994 6) make sure that the CPU is not over clocked.
1995 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1996 8) disable the cache from your BIOS settings
1997 9) install a fan for the video card or exchange video RAM
1998 10) install a better fan for the CPU
1999 11) exchange RAM chips
2000 12) exchange the motherboard.
2002 To compile this driver as a module, choose M here: the
2003 module will be called apm.
2007 config APM_IGNORE_USER_SUSPEND
2008 bool "Ignore USER SUSPEND"
2010 This option will ignore USER SUSPEND requests. On machines with a
2011 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2012 series notebooks, it is necessary to say Y because of a BIOS bug.
2014 config APM_DO_ENABLE
2015 bool "Enable PM at boot time"
2017 Enable APM features at boot time. From page 36 of the APM BIOS
2018 specification: "When disabled, the APM BIOS does not automatically
2019 power manage devices, enter the Standby State, enter the Suspend
2020 State, or take power saving steps in response to CPU Idle calls."
2021 This driver will make CPU Idle calls when Linux is idle (unless this
2022 feature is turned off -- see "Do CPU IDLE calls", below). This
2023 should always save battery power, but more complicated APM features
2024 will be dependent on your BIOS implementation. You may need to turn
2025 this option off if your computer hangs at boot time when using APM
2026 support, or if it beeps continuously instead of suspending. Turn
2027 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2028 T400CDT. This is off by default since most machines do fine without
2033 bool "Make CPU Idle calls when idle"
2035 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2036 On some machines, this can activate improved power savings, such as
2037 a slowed CPU clock rate, when the machine is idle. These idle calls
2038 are made after the idle loop has run for some length of time (e.g.,
2039 333 mS). On some machines, this will cause a hang at boot time or
2040 whenever the CPU becomes idle. (On machines with more than one CPU,
2041 this option does nothing.)
2043 config APM_DISPLAY_BLANK
2044 bool "Enable console blanking using APM"
2046 Enable console blanking using the APM. Some laptops can use this to
2047 turn off the LCD backlight when the screen blanker of the Linux
2048 virtual console blanks the screen. Note that this is only used by
2049 the virtual console screen blanker, and won't turn off the backlight
2050 when using the X Window system. This also doesn't have anything to
2051 do with your VESA-compliant power-saving monitor. Further, this
2052 option doesn't work for all laptops -- it might not turn off your
2053 backlight at all, or it might print a lot of errors to the console,
2054 especially if you are using gpm.
2056 config APM_ALLOW_INTS
2057 bool "Allow interrupts during APM BIOS calls"
2059 Normally we disable external interrupts while we are making calls to
2060 the APM BIOS as a measure to lessen the effects of a badly behaving
2061 BIOS implementation. The BIOS should reenable interrupts if it
2062 needs to. Unfortunately, some BIOSes do not -- especially those in
2063 many of the newer IBM Thinkpads. If you experience hangs when you
2064 suspend, try setting this to Y. Otherwise, say N.
2068 source "drivers/cpufreq/Kconfig"
2070 source "drivers/cpuidle/Kconfig"
2072 source "drivers/idle/Kconfig"
2077 menu "Bus options (PCI etc.)"
2083 Find out whether you have a PCI motherboard. PCI is the name of a
2084 bus system, i.e. the way the CPU talks to the other stuff inside
2085 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2086 VESA. If you have PCI, say Y, otherwise N.
2089 prompt "PCI access mode"
2090 depends on X86_32 && PCI
2093 On PCI systems, the BIOS can be used to detect the PCI devices and
2094 determine their configuration. However, some old PCI motherboards
2095 have BIOS bugs and may crash if this is done. Also, some embedded
2096 PCI-based systems don't have any BIOS at all. Linux can also try to
2097 detect the PCI hardware directly without using the BIOS.
2099 With this option, you can specify how Linux should detect the
2100 PCI devices. If you choose "BIOS", the BIOS will be used,
2101 if you choose "Direct", the BIOS won't be used, and if you
2102 choose "MMConfig", then PCI Express MMCONFIG will be used.
2103 If you choose "Any", the kernel will try MMCONFIG, then the
2104 direct access method and falls back to the BIOS if that doesn't
2105 work. If unsure, go with the default, which is "Any".
2110 config PCI_GOMMCONFIG
2127 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2129 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2132 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2136 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2140 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2144 depends on PCI && XEN
2152 bool "Support mmconfig PCI config space access"
2153 depends on X86_64 && PCI && ACPI
2155 config PCI_CNB20LE_QUIRK
2156 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2159 Read the PCI windows out of the CNB20LE host bridge. This allows
2160 PCI hotplug to work on systems with the CNB20LE chipset which do
2163 There's no public spec for this chipset, and this functionality
2164 is known to be incomplete.
2166 You should say N unless you know you need this.
2168 source "drivers/pci/pcie/Kconfig"
2170 source "drivers/pci/Kconfig"
2172 # x86_64 have no ISA slots, but can have ISA-style DMA.
2174 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2177 Enables ISA-style DMA support for devices requiring such controllers.
2185 Find out whether you have ISA slots on your motherboard. ISA is the
2186 name of a bus system, i.e. the way the CPU talks to the other stuff
2187 inside your box. Other bus systems are PCI, EISA, MicroChannel
2188 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2189 newer boards don't support it. If you have ISA, say Y, otherwise N.
2195 The Extended Industry Standard Architecture (EISA) bus was
2196 developed as an open alternative to the IBM MicroChannel bus.
2198 The EISA bus provided some of the features of the IBM MicroChannel
2199 bus while maintaining backward compatibility with cards made for
2200 the older ISA bus. The EISA bus saw limited use between 1988 and
2201 1995 when it was made obsolete by the PCI bus.
2203 Say Y here if you are building a kernel for an EISA-based machine.
2207 source "drivers/eisa/Kconfig"
2210 tristate "NatSemi SCx200 support"
2212 This provides basic support for National Semiconductor's
2213 (now AMD's) Geode processors. The driver probes for the
2214 PCI-IDs of several on-chip devices, so its a good dependency
2215 for other scx200_* drivers.
2217 If compiled as a module, the driver is named scx200.
2219 config SCx200HR_TIMER
2220 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2224 This driver provides a clocksource built upon the on-chip
2225 27MHz high-resolution timer. Its also a workaround for
2226 NSC Geode SC-1100's buggy TSC, which loses time when the
2227 processor goes idle (as is done by the scheduler). The
2228 other workaround is idle=poll boot option.
2231 bool "One Laptop Per Child support"
2238 Add support for detecting the unique features of the OLPC
2242 bool "OLPC XO-1 Power Management"
2243 depends on OLPC && MFD_CS5535 && PM_SLEEP
2246 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2249 bool "OLPC XO-1 Real Time Clock"
2250 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2252 Add support for the XO-1 real time clock, which can be used as a
2253 programmable wakeup source.
2256 bool "OLPC XO-1 SCI extras"
2257 depends on OLPC && OLPC_XO1_PM
2263 Add support for SCI-based features of the OLPC XO-1 laptop:
2264 - EC-driven system wakeups
2268 - AC adapter status updates
2269 - Battery status updates
2271 config OLPC_XO15_SCI
2272 bool "OLPC XO-1.5 SCI extras"
2273 depends on OLPC && ACPI
2276 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2277 - EC-driven system wakeups
2278 - AC adapter status updates
2279 - Battery status updates
2282 bool "PCEngines ALIX System Support (LED setup)"
2285 This option enables system support for the PCEngines ALIX.
2286 At present this just sets up LEDs for GPIO control on
2287 ALIX2/3/6 boards. However, other system specific setup should
2290 Note: You must still enable the drivers for GPIO and LED support
2291 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2293 Note: You have to set alix.force=1 for boards with Award BIOS.
2296 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2299 This option enables system support for the Soekris Engineering net5501.
2302 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2306 This option enables system support for the Traverse Technologies GEOS.
2309 bool "Technologic Systems TS-5500 platform support"
2311 select CHECK_SIGNATURE
2315 This option enables system support for the Technologic Systems TS-5500.
2321 depends on CPU_SUP_AMD && PCI
2323 source "drivers/pcmcia/Kconfig"
2325 source "drivers/pci/hotplug/Kconfig"
2328 tristate "RapidIO support"
2332 If enabled this option will include drivers and the core
2333 infrastructure code to support RapidIO interconnect devices.
2335 source "drivers/rapidio/Kconfig"
2338 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2340 Firmwares often provide initial graphics framebuffers so the BIOS,
2341 bootloader or kernel can show basic video-output during boot for
2342 user-guidance and debugging. Historically, x86 used the VESA BIOS
2343 Extensions and EFI-framebuffers for this, which are mostly limited
2345 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2346 framebuffers so the new generic system-framebuffer drivers can be
2347 used on x86. If the framebuffer is not compatible with the generic
2348 modes, it is adverticed as fallback platform framebuffer so legacy
2349 drivers like efifb, vesafb and uvesafb can pick it up.
2350 If this option is not selected, all system framebuffers are always
2351 marked as fallback platform framebuffers as usual.
2353 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2354 not be able to pick up generic system framebuffers if this option
2355 is selected. You are highly encouraged to enable simplefb as
2356 replacement if you select this option. simplefb can correctly deal
2357 with generic system framebuffers. But you should still keep vesafb
2358 and others enabled as fallback if a system framebuffer is
2359 incompatible with simplefb.
2366 menu "Executable file formats / Emulations"
2368 source "fs/Kconfig.binfmt"
2370 config IA32_EMULATION
2371 bool "IA32 Emulation"
2374 select COMPAT_BINFMT_ELF
2377 Include code to run legacy 32-bit programs under a
2378 64-bit kernel. You should likely turn this on, unless you're
2379 100% sure that you don't have any 32-bit programs left.
2382 tristate "IA32 a.out support"
2383 depends on IA32_EMULATION
2385 Support old a.out binaries in the 32bit emulation.
2388 bool "x32 ABI for 64-bit mode"
2389 depends on X86_64 && IA32_EMULATION
2391 Include code to run binaries for the x32 native 32-bit ABI
2392 for 64-bit processors. An x32 process gets access to the
2393 full 64-bit register file and wide data path while leaving
2394 pointers at 32 bits for smaller memory footprint.
2396 You will need a recent binutils (2.22 or later) with
2397 elf32_x86_64 support enabled to compile a kernel with this
2402 depends on IA32_EMULATION || X86_X32
2403 select ARCH_WANT_OLD_COMPAT_IPC
2406 config COMPAT_FOR_U64_ALIGNMENT
2409 config SYSVIPC_COMPAT
2421 config HAVE_ATOMIC_IOMAP
2425 config X86_DEV_DMA_OPS
2427 depends on X86_64 || STA2X11
2429 config X86_DMA_REMAP
2433 source "net/Kconfig"
2435 source "drivers/Kconfig"
2437 source "drivers/firmware/Kconfig"
2441 source "arch/x86/Kconfig.debug"
2443 source "security/Kconfig"
2445 source "crypto/Kconfig"
2447 source "arch/x86/kvm/Kconfig"
2449 source "lib/Kconfig"
projects / karo-tx-linux.git / blob