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 ARCH_MIGHT_HAVE_PC_SERIO
27 select HAVE_AOUT if X86_32
28 select HAVE_UNSTABLE_SCHED_CLOCK
29 select ARCH_SUPPORTS_NUMA_BALANCING
30 select ARCH_SUPPORTS_INT128 if X86_64
31 select ARCH_WANTS_PROT_NUMA_PROT_NONE
34 select HAVE_PCSPKR_PLATFORM
35 select HAVE_PERF_EVENTS
36 select HAVE_IOREMAP_PROT
39 select HAVE_MEMBLOCK_NODE_MAP
40 select ARCH_DISCARD_MEMBLOCK
41 select ARCH_WANT_OPTIONAL_GPIOLIB
42 select ARCH_WANT_FRAME_POINTERS
44 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
45 select HAVE_KRETPROBES
47 select HAVE_KPROBES_ON_FTRACE
48 select HAVE_FTRACE_MCOUNT_RECORD
49 select HAVE_FENTRY if X86_64
50 select HAVE_C_RECORDMCOUNT
51 select HAVE_DYNAMIC_FTRACE
52 select HAVE_DYNAMIC_FTRACE_WITH_REGS
53 select HAVE_FUNCTION_TRACER
54 select HAVE_FUNCTION_GRAPH_TRACER
55 select HAVE_FUNCTION_GRAPH_FP_TEST
56 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
57 select HAVE_SYSCALL_TRACEPOINTS
58 select SYSCTL_EXCEPTION_TRACE
61 select HAVE_ARCH_TRACEHOOK
62 select HAVE_GENERIC_DMA_COHERENT if X86_32
63 select HAVE_EFFICIENT_UNALIGNED_ACCESS
64 select USER_STACKTRACE_SUPPORT
65 select HAVE_REGS_AND_STACK_ACCESS_API
66 select HAVE_DMA_API_DEBUG
67 select HAVE_KERNEL_GZIP
68 select HAVE_KERNEL_BZIP2
69 select HAVE_KERNEL_LZMA
71 select HAVE_KERNEL_LZO
72 select HAVE_KERNEL_LZ4
73 select HAVE_HW_BREAKPOINT
74 select HAVE_MIXED_BREAKPOINTS_REGS
76 select HAVE_PERF_EVENTS_NMI
78 select HAVE_PERF_USER_STACK_DUMP
79 select HAVE_DEBUG_KMEMLEAK
81 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
82 select HAVE_CMPXCHG_LOCAL
83 select HAVE_CMPXCHG_DOUBLE
84 select HAVE_ARCH_KMEMCHECK
85 select HAVE_USER_RETURN_NOTIFIER
86 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
87 select HAVE_ARCH_JUMP_LABEL
88 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
90 select GENERIC_FIND_FIRST_BIT
91 select GENERIC_IRQ_PROBE
92 select GENERIC_PENDING_IRQ if SMP
93 select GENERIC_IRQ_SHOW
94 select GENERIC_CLOCKEVENTS_MIN_ADJUST
95 select IRQ_FORCED_THREADING
96 select HAVE_BPF_JIT if X86_64
97 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
99 select ARCH_HAVE_NMI_SAFE_CMPXCHG
101 select DCACHE_WORD_ACCESS
102 select GENERIC_SMP_IDLE_THREAD
103 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
104 select HAVE_ARCH_SECCOMP_FILTER
105 select BUILDTIME_EXTABLE_SORT
106 select GENERIC_CMOS_UPDATE
107 select HAVE_ARCH_SOFT_DIRTY
108 select CLOCKSOURCE_WATCHDOG
109 select GENERIC_CLOCKEVENTS
110 select ARCH_CLOCKSOURCE_DATA if X86_64
111 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
112 select GENERIC_TIME_VSYSCALL if X86_64
113 select KTIME_SCALAR if X86_32
114 select GENERIC_STRNCPY_FROM_USER
115 select GENERIC_STRNLEN_USER
116 select HAVE_CONTEXT_TRACKING if X86_64
117 select HAVE_IRQ_TIME_ACCOUNTING
119 select MODULES_USE_ELF_REL if X86_32
120 select MODULES_USE_ELF_RELA if X86_64
121 select CLONE_BACKWARDS if X86_32
122 select ARCH_USE_BUILTIN_BSWAP
123 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
124 select OLD_SIGACTION if X86_32
125 select COMPAT_OLD_SIGACTION if IA32_EMULATION
127 select HAVE_DEBUG_STACKOVERFLOW
128 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
129 select HAVE_CC_STACKPROTECTOR
131 config INSTRUCTION_DECODER
133 depends on KPROBES || PERF_EVENTS || UPROBES
137 default "elf32-i386" if X86_32
138 default "elf64-x86-64" if X86_64
140 config ARCH_DEFCONFIG
142 default "arch/x86/configs/i386_defconfig" if X86_32
143 default "arch/x86/configs/x86_64_defconfig" if X86_64
145 config LOCKDEP_SUPPORT
148 config STACKTRACE_SUPPORT
151 config HAVE_LATENCYTOP_SUPPORT
160 config NEED_DMA_MAP_STATE
162 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
164 config NEED_SG_DMA_LENGTH
167 config GENERIC_ISA_DMA
169 depends on ISA_DMA_API
174 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
176 config GENERIC_BUG_RELATIVE_POINTERS
179 config GENERIC_HWEIGHT
182 config ARCH_MAY_HAVE_PC_FDC
184 depends on ISA_DMA_API
186 config RWSEM_XCHGADD_ALGORITHM
189 config GENERIC_CALIBRATE_DELAY
192 config ARCH_HAS_CPU_RELAX
195 config ARCH_HAS_CACHE_LINE_SIZE
198 config ARCH_HAS_CPU_AUTOPROBE
201 config HAVE_SETUP_PER_CPU_AREA
204 config NEED_PER_CPU_EMBED_FIRST_CHUNK
207 config NEED_PER_CPU_PAGE_FIRST_CHUNK
210 config ARCH_HIBERNATION_POSSIBLE
213 config ARCH_SUSPEND_POSSIBLE
216 config ARCH_WANT_HUGE_PMD_SHARE
219 config ARCH_WANT_GENERAL_HUGETLB
230 config ARCH_SUPPORTS_OPTIMIZED_INLINING
233 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
236 config HAVE_INTEL_TXT
238 depends on INTEL_IOMMU && ACPI
242 depends on X86_32 && SMP
246 depends on X86_64 && SMP
252 config X86_32_LAZY_GS
254 depends on X86_32 && !CC_STACKPROTECTOR
256 config ARCH_HWEIGHT_CFLAGS
258 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
259 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
261 config ARCH_SUPPORTS_UPROBES
264 source "init/Kconfig"
265 source "kernel/Kconfig.freezer"
267 menu "Processor type and features"
270 bool "DMA memory allocation support" if EXPERT
273 DMA memory allocation support allows devices with less than 32-bit
274 addressing to allocate within the first 16MB of address space.
275 Disable if no such devices will be used.
280 bool "Symmetric multi-processing support"
282 This enables support for systems with more than one CPU. If you have
283 a system with only one CPU, say N. If you have a system with more
286 If you say N here, the kernel will run on uni- and multiprocessor
287 machines, but will use only one CPU of a multiprocessor machine. If
288 you say Y here, the kernel will run on many, but not all,
289 uniprocessor machines. On a uniprocessor machine, the kernel
290 will run faster if you say N here.
292 Note that if you say Y here and choose architecture "586" or
293 "Pentium" under "Processor family", the kernel will not work on 486
294 architectures. Similarly, multiprocessor kernels for the "PPro"
295 architecture may not work on all Pentium based boards.
297 People using multiprocessor machines who say Y here should also say
298 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
299 Management" code will be disabled if you say Y here.
301 See also <file:Documentation/x86/i386/IO-APIC.txt>,
302 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
303 <http://www.tldp.org/docs.html#howto>.
305 If you don't know what to do here, say N.
308 bool "Support x2apic"
309 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
311 This enables x2apic support on CPUs that have this feature.
313 This allows 32-bit apic IDs (so it can support very large systems),
314 and accesses the local apic via MSRs not via mmio.
316 If you don't know what to do here, say N.
319 bool "Enable MPS table" if ACPI || SFI
321 depends on X86_LOCAL_APIC
323 For old smp systems that do not have proper acpi support. Newer systems
324 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
327 bool "Support for big SMP systems with more than 8 CPUs"
328 depends on X86_32 && SMP
330 This option is needed for the systems that have more than 8 CPUs
334 depends on X86_GOLDFISH
337 config X86_EXTENDED_PLATFORM
338 bool "Support for extended (non-PC) x86 platforms"
341 If you disable this option then the kernel will only support
342 standard PC platforms. (which covers the vast majority of
345 If you enable this option then you'll be able to select support
346 for the following (non-PC) 32 bit x86 platforms:
347 Goldfish (Android emulator)
351 SGI 320/540 (Visual Workstation)
352 STA2X11-based (e.g. Northville)
353 Summit/EXA (IBM x440)
354 Unisys ES7000 IA32 series
355 Moorestown MID devices
357 If you have one of these systems, or if you want to build a
358 generic distribution kernel, say Y here - otherwise say N.
362 config X86_EXTENDED_PLATFORM
363 bool "Support for extended (non-PC) x86 platforms"
366 If you disable this option then the kernel will only support
367 standard PC platforms. (which covers the vast majority of
370 If you enable this option then you'll be able to select support
371 for the following (non-PC) 64 bit x86 platforms:
376 If you have one of these systems, or if you want to build a
377 generic distribution kernel, say Y here - otherwise say N.
379 # This is an alphabetically sorted list of 64 bit extended platforms
380 # Please maintain the alphabetic order if and when there are additions
382 bool "Numascale NumaChip"
384 depends on X86_EXTENDED_PLATFORM
387 depends on X86_X2APIC
388 depends on PCI_MMCONFIG
390 Adds support for Numascale NumaChip large-SMP systems. Needed to
391 enable more than ~168 cores.
392 If you don't have one of these, you should say N here.
396 select HYPERVISOR_GUEST
398 depends on X86_64 && PCI
399 depends on X86_EXTENDED_PLATFORM
402 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
403 supposed to run on these EM64T-based machines. Only choose this option
404 if you have one of these machines.
407 bool "SGI Ultraviolet"
409 depends on X86_EXTENDED_PLATFORM
411 depends on X86_X2APIC
413 This option is needed in order to support SGI Ultraviolet systems.
414 If you don't have one of these, you should say N here.
416 # Following is an alphabetically sorted list of 32 bit extended platforms
417 # Please maintain the alphabetic order if and when there are additions
420 bool "Goldfish (Virtual Platform)"
422 depends on X86_EXTENDED_PLATFORM
424 Enable support for the Goldfish virtual platform used primarily
425 for Android development. Unless you are building for the Android
426 Goldfish emulator say N here.
429 bool "CE4100 TV platform"
431 depends on PCI_GODIRECT
433 depends on X86_EXTENDED_PLATFORM
434 select X86_REBOOTFIXUPS
436 select OF_EARLY_FLATTREE
439 Select for the Intel CE media processor (CE4100) SOC.
440 This option compiles in support for the CE4100 SOC for settop
441 boxes and media devices.
444 bool "Intel MID platform support"
446 depends on X86_EXTENDED_PLATFORM
449 depends on X86_IO_APIC
455 select MFD_INTEL_MSIC
457 Select to build a kernel capable of supporting Intel MID (Mobile
458 Internet Device) platform systems which do not have the PCI legacy
459 interfaces. If you are building for a PC class system say N here.
461 Intel MID platforms are based on an Intel processor and chipset which
462 consume less power than most of the x86 derivatives.
464 config X86_INTEL_LPSS
465 bool "Intel Low Power Subsystem Support"
470 Select to build support for Intel Low Power Subsystem such as
471 found on Intel Lynxpoint PCH. Selecting this option enables
472 things like clock tree (common clock framework) and pincontrol
473 which are needed by the LPSS peripheral drivers.
476 bool "RDC R-321x SoC"
478 depends on X86_EXTENDED_PLATFORM
480 select X86_REBOOTFIXUPS
482 This option is needed for RDC R-321x system-on-chip, also known
484 If you don't have one of these chips, you should say N here.
486 config X86_32_NON_STANDARD
487 bool "Support non-standard 32-bit SMP architectures"
488 depends on X86_32 && SMP
489 depends on X86_EXTENDED_PLATFORM
491 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
492 STA2X11, default subarchitectures. It is intended for a generic
493 binary kernel. If you select them all, kernel will probe it
494 one by one and will fallback to default.
496 # Alphabetically sorted list of Non standard 32 bit platforms
499 bool "NUMAQ (IBM/Sequent)"
500 depends on X86_32_NON_STANDARD
505 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
506 NUMA multiquad box. This changes the way that processors are
507 bootstrapped, and uses Clustered Logical APIC addressing mode instead
508 of Flat Logical. You will need a new lynxer.elf file to flash your
509 firmware with - send email to <Martin.Bligh@us.ibm.com>.
511 config X86_SUPPORTS_MEMORY_FAILURE
513 # MCE code calls memory_failure():
515 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
516 depends on !X86_NUMAQ
517 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
518 depends on X86_64 || !SPARSEMEM
519 select ARCH_SUPPORTS_MEMORY_FAILURE
522 bool "SGI 320/540 (Visual Workstation)"
523 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
524 depends on X86_32_NON_STANDARD
526 The SGI Visual Workstation series is an IA32-based workstation
527 based on SGI systems chips with some legacy PC hardware attached.
529 Say Y here to create a kernel to run on the SGI 320 or 540.
531 A kernel compiled for the Visual Workstation will run on general
532 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
535 bool "STA2X11 Companion Chip Support"
536 depends on X86_32_NON_STANDARD && PCI
537 select X86_DEV_DMA_OPS
541 select ARCH_REQUIRE_GPIOLIB
544 This adds support for boards based on the STA2X11 IO-Hub,
545 a.k.a. "ConneXt". The chip is used in place of the standard
546 PC chipset, so all "standard" peripherals are missing. If this
547 option is selected the kernel will still be able to boot on
548 standard PC machines.
551 bool "Summit/EXA (IBM x440)"
552 depends on X86_32_NON_STANDARD
554 This option is needed for IBM systems that use the Summit/EXA chipset.
555 In particular, it is needed for the x440.
558 bool "Unisys ES7000 IA32 series"
559 depends on X86_32_NON_STANDARD && X86_BIGSMP
561 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
562 supposed to run on an IA32-based Unisys ES7000 system.
565 tristate "Eurobraille/Iris poweroff module"
568 The Iris machines from EuroBraille do not have APM or ACPI support
569 to shut themselves down properly. A special I/O sequence is
570 needed to do so, which is what this module does at
573 This is only for Iris machines from EuroBraille.
577 config SCHED_OMIT_FRAME_POINTER
579 prompt "Single-depth WCHAN output"
582 Calculate simpler /proc/<PID>/wchan values. If this option
583 is disabled then wchan values will recurse back to the
584 caller function. This provides more accurate wchan values,
585 at the expense of slightly more scheduling overhead.
587 If in doubt, say "Y".
589 menuconfig HYPERVISOR_GUEST
590 bool "Linux guest support"
592 Say Y here to enable options for running Linux under various hyper-
593 visors. This option enables basic hypervisor detection and platform
596 If you say N, all options in this submenu will be skipped and
597 disabled, and Linux guest support won't be built in.
602 bool "Enable paravirtualization code"
604 This changes the kernel so it can modify itself when it is run
605 under a hypervisor, potentially improving performance significantly
606 over full virtualization. However, when run without a hypervisor
607 the kernel is theoretically slower and slightly larger.
609 config PARAVIRT_DEBUG
610 bool "paravirt-ops debugging"
611 depends on PARAVIRT && DEBUG_KERNEL
613 Enable to debug paravirt_ops internals. Specifically, BUG if
614 a paravirt_op is missing when it is called.
616 config PARAVIRT_SPINLOCKS
617 bool "Paravirtualization layer for spinlocks"
618 depends on PARAVIRT && SMP
619 select UNINLINE_SPIN_UNLOCK
621 Paravirtualized spinlocks allow a pvops backend to replace the
622 spinlock implementation with something virtualization-friendly
623 (for example, block the virtual CPU rather than spinning).
625 It has a minimal impact on native kernels and gives a nice performance
626 benefit on paravirtualized KVM / Xen kernels.
628 If you are unsure how to answer this question, answer Y.
630 source "arch/x86/xen/Kconfig"
633 bool "KVM Guest support (including kvmclock)"
635 select PARAVIRT_CLOCK
638 This option enables various optimizations for running under the KVM
639 hypervisor. It includes a paravirtualized clock, so that instead
640 of relying on a PIT (or probably other) emulation by the
641 underlying device model, the host provides the guest with
642 timing infrastructure such as time of day, and system time
645 bool "Enable debug information for KVM Guests in debugfs"
646 depends on KVM_GUEST && DEBUG_FS
649 This option enables collection of various statistics for KVM guest.
650 Statistics are displayed in debugfs filesystem. Enabling this option
651 may incur significant overhead.
653 source "arch/x86/lguest/Kconfig"
655 config PARAVIRT_TIME_ACCOUNTING
656 bool "Paravirtual steal time accounting"
660 Select this option to enable fine granularity task steal time
661 accounting. Time spent executing other tasks in parallel with
662 the current vCPU is discounted from the vCPU power. To account for
663 that, there can be a small performance impact.
665 If in doubt, say N here.
667 config PARAVIRT_CLOCK
670 endif #HYPERVISOR_GUEST
678 This option adds a kernel parameter 'memtest', which allows memtest
680 memtest=0, mean disabled; -- default
681 memtest=1, mean do 1 test pattern;
683 memtest=4, mean do 4 test patterns.
684 If you are unsure how to answer this question, answer N.
686 config X86_SUMMIT_NUMA
688 depends on X86_32 && NUMA && X86_32_NON_STANDARD
690 config X86_CYCLONE_TIMER
692 depends on X86_SUMMIT
694 source "arch/x86/Kconfig.cpu"
698 prompt "HPET Timer Support" if X86_32
700 Use the IA-PC HPET (High Precision Event Timer) to manage
701 time in preference to the PIT and RTC, if a HPET is
703 HPET is the next generation timer replacing legacy 8254s.
704 The HPET provides a stable time base on SMP
705 systems, unlike the TSC, but it is more expensive to access,
706 as it is off-chip. You can find the HPET spec at
707 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
709 You can safely choose Y here. However, HPET will only be
710 activated if the platform and the BIOS support this feature.
711 Otherwise the 8254 will be used for timing services.
713 Choose N to continue using the legacy 8254 timer.
715 config HPET_EMULATE_RTC
717 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
720 def_bool y if X86_INTEL_MID
721 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
723 depends on X86_INTEL_MID && SFI
725 APB timer is the replacement for 8254, HPET on X86 MID platforms.
726 The APBT provides a stable time base on SMP
727 systems, unlike the TSC, but it is more expensive to access,
728 as it is off-chip. APB timers are always running regardless of CPU
729 C states, they are used as per CPU clockevent device when possible.
731 # Mark as expert because too many people got it wrong.
732 # The code disables itself when not needed.
735 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
736 bool "Enable DMI scanning" if EXPERT
738 Enabled scanning of DMI to identify machine quirks. Say Y
739 here unless you have verified that your setup is not
740 affected by entries in the DMI blacklist. Required by PNP
744 bool "Old AMD GART IOMMU support"
746 depends on X86_64 && PCI && AMD_NB
748 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
749 GART based hardware IOMMUs.
751 The GART supports full DMA access for devices with 32-bit access
752 limitations, on systems with more than 3 GB. This is usually needed
753 for USB, sound, many IDE/SATA chipsets and some other devices.
755 Newer systems typically have a modern AMD IOMMU, supported via
756 the CONFIG_AMD_IOMMU=y config option.
758 In normal configurations this driver is only active when needed:
759 there's more than 3 GB of memory and the system contains a
760 32-bit limited device.
765 bool "IBM Calgary IOMMU support"
767 depends on X86_64 && PCI
769 Support for hardware IOMMUs in IBM's xSeries x366 and x460
770 systems. Needed to run systems with more than 3GB of memory
771 properly with 32-bit PCI devices that do not support DAC
772 (Double Address Cycle). Calgary also supports bus level
773 isolation, where all DMAs pass through the IOMMU. This
774 prevents them from going anywhere except their intended
775 destination. This catches hard-to-find kernel bugs and
776 mis-behaving drivers and devices that do not use the DMA-API
777 properly to set up their DMA buffers. The IOMMU can be
778 turned off at boot time with the iommu=off parameter.
779 Normally the kernel will make the right choice by itself.
782 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
784 prompt "Should Calgary be enabled by default?"
785 depends on CALGARY_IOMMU
787 Should Calgary be enabled by default? if you choose 'y', Calgary
788 will be used (if it exists). If you choose 'n', Calgary will not be
789 used even if it exists. If you choose 'n' and would like to use
790 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
793 # need this always selected by IOMMU for the VIA workaround
797 Support for software bounce buffers used on x86-64 systems
798 which don't have a hardware IOMMU. Using this PCI devices
799 which can only access 32-bits of memory can be used on systems
800 with more than 3 GB of memory.
805 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
808 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
809 depends on X86_64 && SMP && DEBUG_KERNEL
810 select CPUMASK_OFFSTACK
812 Enable maximum number of CPUS and NUMA Nodes for this architecture.
816 int "Maximum number of CPUs" if SMP && !MAXSMP
817 range 2 8 if SMP && X86_32 && !X86_BIGSMP
818 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
819 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
821 default "8192" if MAXSMP
822 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
825 This allows you to specify the maximum number of CPUs which this
826 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
827 supported value is 4096, otherwise the maximum value is 512. The
828 minimum value which makes sense is 2.
830 This is purely to save memory - each supported CPU adds
831 approximately eight kilobytes to the kernel image.
834 bool "SMT (Hyperthreading) scheduler support"
837 SMT scheduler support improves the CPU scheduler's decision making
838 when dealing with Intel Pentium 4 chips with HyperThreading at a
839 cost of slightly increased overhead in some places. If unsure say
844 prompt "Multi-core scheduler support"
847 Multi-core scheduler support improves the CPU scheduler's decision
848 making when dealing with multi-core CPU chips at a cost of slightly
849 increased overhead in some places. If unsure say N here.
851 source "kernel/Kconfig.preempt"
854 bool "Local APIC support on uniprocessors"
855 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
857 A local APIC (Advanced Programmable Interrupt Controller) is an
858 integrated interrupt controller in the CPU. If you have a single-CPU
859 system which has a processor with a local APIC, you can say Y here to
860 enable and use it. If you say Y here even though your machine doesn't
861 have a local APIC, then the kernel will still run with no slowdown at
862 all. The local APIC supports CPU-generated self-interrupts (timer,
863 performance counters), and the NMI watchdog which detects hard
867 bool "IO-APIC support on uniprocessors"
868 depends on X86_UP_APIC
870 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
871 SMP-capable replacement for PC-style interrupt controllers. Most
872 SMP systems and many recent uniprocessor systems have one.
874 If you have a single-CPU system with an IO-APIC, you can say Y here
875 to use it. If you say Y here even though your machine doesn't have
876 an IO-APIC, then the kernel will still run with no slowdown at all.
878 config X86_LOCAL_APIC
880 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
884 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
886 config X86_VISWS_APIC
888 depends on X86_32 && X86_VISWS
890 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
891 bool "Reroute for broken boot IRQs"
892 depends on X86_IO_APIC
894 This option enables a workaround that fixes a source of
895 spurious interrupts. This is recommended when threaded
896 interrupt handling is used on systems where the generation of
897 superfluous "boot interrupts" cannot be disabled.
899 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
900 entry in the chipset's IO-APIC is masked (as, e.g. the RT
901 kernel does during interrupt handling). On chipsets where this
902 boot IRQ generation cannot be disabled, this workaround keeps
903 the original IRQ line masked so that only the equivalent "boot
904 IRQ" is delivered to the CPUs. The workaround also tells the
905 kernel to set up the IRQ handler on the boot IRQ line. In this
906 way only one interrupt is delivered to the kernel. Otherwise
907 the spurious second interrupt may cause the kernel to bring
908 down (vital) interrupt lines.
910 Only affects "broken" chipsets. Interrupt sharing may be
911 increased on these systems.
914 bool "Machine Check / overheating reporting"
917 Machine Check support allows the processor to notify the
918 kernel if it detects a problem (e.g. overheating, data corruption).
919 The action the kernel takes depends on the severity of the problem,
920 ranging from warning messages to halting the machine.
924 prompt "Intel MCE features"
925 depends on X86_MCE && X86_LOCAL_APIC
927 Additional support for intel specific MCE features such as
932 prompt "AMD MCE features"
933 depends on X86_MCE && X86_LOCAL_APIC
935 Additional support for AMD specific MCE features such as
936 the DRAM Error Threshold.
938 config X86_ANCIENT_MCE
939 bool "Support for old Pentium 5 / WinChip machine checks"
940 depends on X86_32 && X86_MCE
942 Include support for machine check handling on old Pentium 5 or WinChip
943 systems. These typically need to be enabled explicitly on the command
946 config X86_MCE_THRESHOLD
947 depends on X86_MCE_AMD || X86_MCE_INTEL
950 config X86_MCE_INJECT
952 tristate "Machine check injector support"
954 Provide support for injecting machine checks for testing purposes.
955 If you don't know what a machine check is and you don't do kernel
956 QA it is safe to say n.
958 config X86_THERMAL_VECTOR
960 depends on X86_MCE_INTEL
963 bool "Enable VM86 support" if EXPERT
967 This option is required by programs like DOSEMU to run 16-bit legacy
968 code on X86 processors. It also may be needed by software like
969 XFree86 to initialize some video cards via BIOS. Disabling this
970 option saves about 6k.
973 tristate "Toshiba Laptop support"
976 This adds a driver to safely access the System Management Mode of
977 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
978 not work on models with a Phoenix BIOS. The System Management Mode
979 is used to set the BIOS and power saving options on Toshiba portables.
981 For information on utilities to make use of this driver see the
982 Toshiba Linux utilities web site at:
983 <http://www.buzzard.org.uk/toshiba/>.
985 Say Y if you intend to run this kernel on a Toshiba portable.
989 tristate "Dell laptop support"
992 This adds a driver to safely access the System Management Mode
993 of the CPU on the Dell Inspiron 8000. The System Management Mode
994 is used to read cpu temperature and cooling fan status and to
995 control the fans on the I8K portables.
997 This driver has been tested only on the Inspiron 8000 but it may
998 also work with other Dell laptops. You can force loading on other
999 models by passing the parameter `force=1' to the module. Use at
1002 For information on utilities to make use of this driver see the
1003 I8K Linux utilities web site at:
1004 <http://people.debian.org/~dz/i8k/>
1006 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1009 config X86_REBOOTFIXUPS
1010 bool "Enable X86 board specific fixups for reboot"
1013 This enables chipset and/or board specific fixups to be done
1014 in order to get reboot to work correctly. This is only needed on
1015 some combinations of hardware and BIOS. The symptom, for which
1016 this config is intended, is when reboot ends with a stalled/hung
1019 Currently, the only fixup is for the Geode machines using
1020 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1022 Say Y if you want to enable the fixup. Currently, it's safe to
1023 enable this option even if you don't need it.
1027 tristate "CPU microcode loading support"
1028 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1032 If you say Y here, you will be able to update the microcode on
1033 certain Intel and AMD processors. The Intel support is for the
1034 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1035 Xeon etc. The AMD support is for families 0x10 and later. You will
1036 obviously need the actual microcode binary data itself which is not
1037 shipped with the Linux kernel.
1039 This option selects the general module only, you need to select
1040 at least one vendor specific module as well.
1042 To compile this driver as a module, choose M here: the module
1043 will be called microcode.
1045 config MICROCODE_INTEL
1046 bool "Intel microcode loading support"
1047 depends on MICROCODE
1051 This options enables microcode patch loading support for Intel
1054 For latest news and information on obtaining all the required
1055 Intel ingredients for this driver, check:
1056 <http://www.urbanmyth.org/microcode/>.
1058 config MICROCODE_AMD
1059 bool "AMD microcode loading support"
1060 depends on MICROCODE
1063 If you select this option, microcode patch loading support for AMD
1064 processors will be enabled.
1066 config MICROCODE_OLD_INTERFACE
1068 depends on MICROCODE
1070 config MICROCODE_INTEL_EARLY
1073 config MICROCODE_AMD_EARLY
1076 config MICROCODE_EARLY
1077 bool "Early load microcode"
1078 depends on MICROCODE=y && BLK_DEV_INITRD
1079 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1080 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1083 This option provides functionality to read additional microcode data
1084 at the beginning of initrd image. The data tells kernel to load
1085 microcode to CPU's as early as possible. No functional change if no
1086 microcode data is glued to the initrd, therefore it's safe to say Y.
1089 tristate "/dev/cpu/*/msr - Model-specific register support"
1091 This device gives privileged processes access to the x86
1092 Model-Specific Registers (MSRs). It is a character device with
1093 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1094 MSR accesses are directed to a specific CPU on multi-processor
1098 tristate "/dev/cpu/*/cpuid - CPU information support"
1100 This device gives processes access to the x86 CPUID instruction to
1101 be executed on a specific processor. It is a character device
1102 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1106 prompt "High Memory Support"
1107 default HIGHMEM64G if X86_NUMAQ
1113 depends on !X86_NUMAQ
1115 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1116 However, the address space of 32-bit x86 processors is only 4
1117 Gigabytes large. That means that, if you have a large amount of
1118 physical memory, not all of it can be "permanently mapped" by the
1119 kernel. The physical memory that's not permanently mapped is called
1122 If you are compiling a kernel which will never run on a machine with
1123 more than 1 Gigabyte total physical RAM, answer "off" here (default
1124 choice and suitable for most users). This will result in a "3GB/1GB"
1125 split: 3GB are mapped so that each process sees a 3GB virtual memory
1126 space and the remaining part of the 4GB virtual memory space is used
1127 by the kernel to permanently map as much physical memory as
1130 If the machine has between 1 and 4 Gigabytes physical RAM, then
1133 If more than 4 Gigabytes is used then answer "64GB" here. This
1134 selection turns Intel PAE (Physical Address Extension) mode on.
1135 PAE implements 3-level paging on IA32 processors. PAE is fully
1136 supported by Linux, PAE mode is implemented on all recent Intel
1137 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1138 then the kernel will not boot on CPUs that don't support PAE!
1140 The actual amount of total physical memory will either be
1141 auto detected or can be forced by using a kernel command line option
1142 such as "mem=256M". (Try "man bootparam" or see the documentation of
1143 your boot loader (lilo or loadlin) about how to pass options to the
1144 kernel at boot time.)
1146 If unsure, say "off".
1150 depends on !X86_NUMAQ
1152 Select this if you have a 32-bit processor and between 1 and 4
1153 gigabytes of physical RAM.
1160 Select this if you have a 32-bit processor and more than 4
1161 gigabytes of physical RAM.
1166 prompt "Memory split" if EXPERT
1170 Select the desired split between kernel and user memory.
1172 If the address range available to the kernel is less than the
1173 physical memory installed, the remaining memory will be available
1174 as "high memory". Accessing high memory is a little more costly
1175 than low memory, as it needs to be mapped into the kernel first.
1176 Note that increasing the kernel address space limits the range
1177 available to user programs, making the address space there
1178 tighter. Selecting anything other than the default 3G/1G split
1179 will also likely make your kernel incompatible with binary-only
1182 If you are not absolutely sure what you are doing, leave this
1186 bool "3G/1G user/kernel split"
1187 config VMSPLIT_3G_OPT
1189 bool "3G/1G user/kernel split (for full 1G low memory)"
1191 bool "2G/2G user/kernel split"
1192 config VMSPLIT_2G_OPT
1194 bool "2G/2G user/kernel split (for full 2G low memory)"
1196 bool "1G/3G user/kernel split"
1201 default 0xB0000000 if VMSPLIT_3G_OPT
1202 default 0x80000000 if VMSPLIT_2G
1203 default 0x78000000 if VMSPLIT_2G_OPT
1204 default 0x40000000 if VMSPLIT_1G
1210 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1213 bool "PAE (Physical Address Extension) Support"
1214 depends on X86_32 && !HIGHMEM4G
1216 PAE is required for NX support, and furthermore enables
1217 larger swapspace support for non-overcommit purposes. It
1218 has the cost of more pagetable lookup overhead, and also
1219 consumes more pagetable space per process.
1221 config ARCH_PHYS_ADDR_T_64BIT
1223 depends on X86_64 || X86_PAE
1225 config ARCH_DMA_ADDR_T_64BIT
1227 depends on X86_64 || HIGHMEM64G
1229 config DIRECT_GBPAGES
1230 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1234 Allow the kernel linear mapping to use 1GB pages on CPUs that
1235 support it. This can improve the kernel's performance a tiny bit by
1236 reducing TLB pressure. If in doubt, say "Y".
1238 # Common NUMA Features
1240 bool "Numa Memory Allocation and Scheduler Support"
1242 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1243 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1245 Enable NUMA (Non Uniform Memory Access) support.
1247 The kernel will try to allocate memory used by a CPU on the
1248 local memory controller of the CPU and add some more
1249 NUMA awareness to the kernel.
1251 For 64-bit this is recommended if the system is Intel Core i7
1252 (or later), AMD Opteron, or EM64T NUMA.
1254 For 32-bit this is only needed on (rare) 32-bit-only platforms
1255 that support NUMA topologies, such as NUMAQ / Summit, or if you
1256 boot a 32-bit kernel on a 64-bit NUMA platform.
1258 Otherwise, you should say N.
1260 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1261 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1265 prompt "Old style AMD Opteron NUMA detection"
1266 depends on X86_64 && NUMA && PCI
1268 Enable AMD NUMA node topology detection. You should say Y here if
1269 you have a multi processor AMD system. This uses an old method to
1270 read the NUMA configuration directly from the builtin Northbridge
1271 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1272 which also takes priority if both are compiled in.
1274 config X86_64_ACPI_NUMA
1276 prompt "ACPI NUMA detection"
1277 depends on X86_64 && NUMA && ACPI && PCI
1280 Enable ACPI SRAT based node topology detection.
1282 # Some NUMA nodes have memory ranges that span
1283 # other nodes. Even though a pfn is valid and
1284 # between a node's start and end pfns, it may not
1285 # reside on that node. See memmap_init_zone()
1287 config NODES_SPAN_OTHER_NODES
1289 depends on X86_64_ACPI_NUMA
1292 bool "NUMA emulation"
1295 Enable NUMA emulation. A flat machine will be split
1296 into virtual nodes when booted with "numa=fake=N", where N is the
1297 number of nodes. This is only useful for debugging.
1300 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1302 default "10" if MAXSMP
1303 default "6" if X86_64
1304 default "4" if X86_NUMAQ
1306 depends on NEED_MULTIPLE_NODES
1308 Specify the maximum number of NUMA Nodes available on the target
1309 system. Increases memory reserved to accommodate various tables.
1311 config ARCH_HAVE_MEMORY_PRESENT
1313 depends on X86_32 && DISCONTIGMEM
1315 config NEED_NODE_MEMMAP_SIZE
1317 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1319 config ARCH_FLATMEM_ENABLE
1321 depends on X86_32 && !NUMA
1323 config ARCH_DISCONTIGMEM_ENABLE
1325 depends on NUMA && X86_32
1327 config ARCH_DISCONTIGMEM_DEFAULT
1329 depends on NUMA && X86_32
1331 config ARCH_SPARSEMEM_ENABLE
1333 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1334 select SPARSEMEM_STATIC if X86_32
1335 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1337 config ARCH_SPARSEMEM_DEFAULT
1341 config ARCH_SELECT_MEMORY_MODEL
1343 depends on ARCH_SPARSEMEM_ENABLE
1345 config ARCH_MEMORY_PROBE
1346 bool "Enable sysfs memory/probe interface"
1347 depends on X86_64 && MEMORY_HOTPLUG
1349 This option enables a sysfs memory/probe interface for testing.
1350 See Documentation/memory-hotplug.txt for more information.
1351 If you are unsure how to answer this question, answer N.
1353 config ARCH_PROC_KCORE_TEXT
1355 depends on X86_64 && PROC_KCORE
1357 config ILLEGAL_POINTER_VALUE
1360 default 0xdead000000000000 if X86_64
1365 bool "Allocate 3rd-level pagetables from highmem"
1368 The VM uses one page table entry for each page of physical memory.
1369 For systems with a lot of RAM, this can be wasteful of precious
1370 low memory. Setting this option will put user-space page table
1371 entries in high memory.
1373 config X86_CHECK_BIOS_CORRUPTION
1374 bool "Check for low memory corruption"
1376 Periodically check for memory corruption in low memory, which
1377 is suspected to be caused by BIOS. Even when enabled in the
1378 configuration, it is disabled at runtime. Enable it by
1379 setting "memory_corruption_check=1" on the kernel command
1380 line. By default it scans the low 64k of memory every 60
1381 seconds; see the memory_corruption_check_size and
1382 memory_corruption_check_period parameters in
1383 Documentation/kernel-parameters.txt to adjust this.
1385 When enabled with the default parameters, this option has
1386 almost no overhead, as it reserves a relatively small amount
1387 of memory and scans it infrequently. It both detects corruption
1388 and prevents it from affecting the running system.
1390 It is, however, intended as a diagnostic tool; if repeatable
1391 BIOS-originated corruption always affects the same memory,
1392 you can use memmap= to prevent the kernel from using that
1395 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1396 bool "Set the default setting of memory_corruption_check"
1397 depends on X86_CHECK_BIOS_CORRUPTION
1400 Set whether the default state of memory_corruption_check is
1403 config X86_RESERVE_LOW
1404 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1408 Specify the amount of low memory to reserve for the BIOS.
1410 The first page contains BIOS data structures that the kernel
1411 must not use, so that page must always be reserved.
1413 By default we reserve the first 64K of physical RAM, as a
1414 number of BIOSes are known to corrupt that memory range
1415 during events such as suspend/resume or monitor cable
1416 insertion, so it must not be used by the kernel.
1418 You can set this to 4 if you are absolutely sure that you
1419 trust the BIOS to get all its memory reservations and usages
1420 right. If you know your BIOS have problems beyond the
1421 default 64K area, you can set this to 640 to avoid using the
1422 entire low memory range.
1424 If you have doubts about the BIOS (e.g. suspend/resume does
1425 not work or there's kernel crashes after certain hardware
1426 hotplug events) then you might want to enable
1427 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1428 typical corruption patterns.
1430 Leave this to the default value of 64 if you are unsure.
1432 config MATH_EMULATION
1434 prompt "Math emulation" if X86_32
1436 Linux can emulate a math coprocessor (used for floating point
1437 operations) if you don't have one. 486DX and Pentium processors have
1438 a math coprocessor built in, 486SX and 386 do not, unless you added
1439 a 487DX or 387, respectively. (The messages during boot time can
1440 give you some hints here ["man dmesg"].) Everyone needs either a
1441 coprocessor or this emulation.
1443 If you don't have a math coprocessor, you need to say Y here; if you
1444 say Y here even though you have a coprocessor, the coprocessor will
1445 be used nevertheless. (This behavior can be changed with the kernel
1446 command line option "no387", which comes handy if your coprocessor
1447 is broken. Try "man bootparam" or see the documentation of your boot
1448 loader (lilo or loadlin) about how to pass options to the kernel at
1449 boot time.) This means that it is a good idea to say Y here if you
1450 intend to use this kernel on different machines.
1452 More information about the internals of the Linux math coprocessor
1453 emulation can be found in <file:arch/x86/math-emu/README>.
1455 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1456 kernel, it won't hurt.
1460 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1462 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1463 the Memory Type Range Registers (MTRRs) may be used to control
1464 processor access to memory ranges. This is most useful if you have
1465 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1466 allows bus write transfers to be combined into a larger transfer
1467 before bursting over the PCI/AGP bus. This can increase performance
1468 of image write operations 2.5 times or more. Saying Y here creates a
1469 /proc/mtrr file which may be used to manipulate your processor's
1470 MTRRs. Typically the X server should use this.
1472 This code has a reasonably generic interface so that similar
1473 control registers on other processors can be easily supported
1476 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1477 Registers (ARRs) which provide a similar functionality to MTRRs. For
1478 these, the ARRs are used to emulate the MTRRs.
1479 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1480 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1481 write-combining. All of these processors are supported by this code
1482 and it makes sense to say Y here if you have one of them.
1484 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1485 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1486 can lead to all sorts of problems, so it's good to say Y here.
1488 You can safely say Y even if your machine doesn't have MTRRs, you'll
1489 just add about 9 KB to your kernel.
1491 See <file:Documentation/x86/mtrr.txt> for more information.
1493 config MTRR_SANITIZER
1495 prompt "MTRR cleanup support"
1498 Convert MTRR layout from continuous to discrete, so X drivers can
1499 add writeback entries.
1501 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1502 The largest mtrr entry size for a continuous block can be set with
1507 config MTRR_SANITIZER_ENABLE_DEFAULT
1508 int "MTRR cleanup enable value (0-1)"
1511 depends on MTRR_SANITIZER
1513 Enable mtrr cleanup default value
1515 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1516 int "MTRR cleanup spare reg num (0-7)"
1519 depends on MTRR_SANITIZER
1521 mtrr cleanup spare entries default, it can be changed via
1522 mtrr_spare_reg_nr=N on the kernel command line.
1526 prompt "x86 PAT support" if EXPERT
1529 Use PAT attributes to setup page level cache control.
1531 PATs are the modern equivalents of MTRRs and are much more
1532 flexible than MTRRs.
1534 Say N here if you see bootup problems (boot crash, boot hang,
1535 spontaneous reboots) or a non-working video driver.
1539 config ARCH_USES_PG_UNCACHED
1545 prompt "x86 architectural random number generator" if EXPERT
1547 Enable the x86 architectural RDRAND instruction
1548 (Intel Bull Mountain technology) to generate random numbers.
1549 If supported, this is a high bandwidth, cryptographically
1550 secure hardware random number generator.
1554 prompt "Supervisor Mode Access Prevention" if EXPERT
1556 Supervisor Mode Access Prevention (SMAP) is a security
1557 feature in newer Intel processors. There is a small
1558 performance cost if this enabled and turned on; there is
1559 also a small increase in the kernel size if this is enabled.
1564 bool "EFI runtime service support"
1568 This enables the kernel to use EFI runtime services that are
1569 available (such as the EFI variable services).
1571 This option is only useful on systems that have EFI firmware.
1572 In addition, you should use the latest ELILO loader available
1573 at <http://elilo.sourceforge.net> in order to take advantage
1574 of EFI runtime services. However, even with this option, the
1575 resultant kernel should continue to boot on existing non-EFI
1579 bool "EFI stub support"
1582 This kernel feature allows a bzImage to be loaded directly
1583 by EFI firmware without the use of a bootloader.
1585 See Documentation/efi-stub.txt for more information.
1589 prompt "Enable seccomp to safely compute untrusted bytecode"
1591 This kernel feature is useful for number crunching applications
1592 that may need to compute untrusted bytecode during their
1593 execution. By using pipes or other transports made available to
1594 the process as file descriptors supporting the read/write
1595 syscalls, it's possible to isolate those applications in
1596 their own address space using seccomp. Once seccomp is
1597 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1598 and the task is only allowed to execute a few safe syscalls
1599 defined by each seccomp mode.
1601 If unsure, say Y. Only embedded should say N here.
1603 source kernel/Kconfig.hz
1606 bool "kexec system call"
1608 kexec is a system call that implements the ability to shutdown your
1609 current kernel, and to start another kernel. It is like a reboot
1610 but it is independent of the system firmware. And like a reboot
1611 you can start any kernel with it, not just Linux.
1613 The name comes from the similarity to the exec system call.
1615 It is an ongoing process to be certain the hardware in a machine
1616 is properly shutdown, so do not be surprised if this code does not
1617 initially work for you. As of this writing the exact hardware
1618 interface is strongly in flux, so no good recommendation can be
1622 bool "kernel crash dumps"
1623 depends on X86_64 || (X86_32 && HIGHMEM)
1625 Generate crash dump after being started by kexec.
1626 This should be normally only set in special crash dump kernels
1627 which are loaded in the main kernel with kexec-tools into
1628 a specially reserved region and then later executed after
1629 a crash by kdump/kexec. The crash dump kernel must be compiled
1630 to a memory address not used by the main kernel or BIOS using
1631 PHYSICAL_START, or it must be built as a relocatable image
1632 (CONFIG_RELOCATABLE=y).
1633 For more details see Documentation/kdump/kdump.txt
1637 depends on KEXEC && HIBERNATION
1639 Jump between original kernel and kexeced kernel and invoke
1640 code in physical address mode via KEXEC
1642 config PHYSICAL_START
1643 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1646 This gives the physical address where the kernel is loaded.
1648 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1649 bzImage will decompress itself to above physical address and
1650 run from there. Otherwise, bzImage will run from the address where
1651 it has been loaded by the boot loader and will ignore above physical
1654 In normal kdump cases one does not have to set/change this option
1655 as now bzImage can be compiled as a completely relocatable image
1656 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1657 address. This option is mainly useful for the folks who don't want
1658 to use a bzImage for capturing the crash dump and want to use a
1659 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1660 to be specifically compiled to run from a specific memory area
1661 (normally a reserved region) and this option comes handy.
1663 So if you are using bzImage for capturing the crash dump,
1664 leave the value here unchanged to 0x1000000 and set
1665 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1666 for capturing the crash dump change this value to start of
1667 the reserved region. In other words, it can be set based on
1668 the "X" value as specified in the "crashkernel=YM@XM"
1669 command line boot parameter passed to the panic-ed
1670 kernel. Please take a look at Documentation/kdump/kdump.txt
1671 for more details about crash dumps.
1673 Usage of bzImage for capturing the crash dump is recommended as
1674 one does not have to build two kernels. Same kernel can be used
1675 as production kernel and capture kernel. Above option should have
1676 gone away after relocatable bzImage support is introduced. But it
1677 is present because there are users out there who continue to use
1678 vmlinux for dump capture. This option should go away down the
1681 Don't change this unless you know what you are doing.
1684 bool "Build a relocatable kernel"
1687 This builds a kernel image that retains relocation information
1688 so it can be loaded someplace besides the default 1MB.
1689 The relocations tend to make the kernel binary about 10% larger,
1690 but are discarded at runtime.
1692 One use is for the kexec on panic case where the recovery kernel
1693 must live at a different physical address than the primary
1696 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1697 it has been loaded at and the compile time physical address
1698 (CONFIG_PHYSICAL_START) is used as the minimum location.
1700 config RANDOMIZE_BASE
1701 bool "Randomize the address of the kernel image"
1702 depends on RELOCATABLE
1703 depends on !HIBERNATION
1706 Randomizes the physical and virtual address at which the
1707 kernel image is decompressed, as a security feature that
1708 deters exploit attempts relying on knowledge of the location
1709 of kernel internals.
1711 Entropy is generated using the RDRAND instruction if it is
1712 supported. If RDTSC is supported, it is used as well. If
1713 neither RDRAND nor RDTSC are supported, then randomness is
1714 read from the i8254 timer.
1716 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1717 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1718 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1719 minimum of 2MiB, only 10 bits of entropy is theoretically
1720 possible. At best, due to page table layouts, 64-bit can use
1721 9 bits of entropy and 32-bit uses 8 bits.
1725 config RANDOMIZE_BASE_MAX_OFFSET
1726 hex "Maximum kASLR offset allowed" if EXPERT
1727 depends on RANDOMIZE_BASE
1728 range 0x0 0x20000000 if X86_32
1729 default "0x20000000" if X86_32
1730 range 0x0 0x40000000 if X86_64
1731 default "0x40000000" if X86_64
1733 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1734 memory is used to determine the maximal offset in bytes that will
1735 be applied to the kernel when kernel Address Space Layout
1736 Randomization (kASLR) is active. This must be a multiple of
1739 On 32-bit this is limited to 512MiB by page table layouts. The
1742 On 64-bit this is limited by how the kernel fixmap page table is
1743 positioned, so this cannot be larger than 1GiB currently. Without
1744 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1745 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1746 modules area will shrink to compensate, up to the current maximum
1747 1GiB to 1GiB split. The default is 1GiB.
1749 If unsure, leave at the default value.
1751 # Relocation on x86 needs some additional build support
1752 config X86_NEED_RELOCS
1754 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1756 config PHYSICAL_ALIGN
1757 hex "Alignment value to which kernel should be aligned"
1759 range 0x2000 0x1000000 if X86_32
1760 range 0x200000 0x1000000 if X86_64
1762 This value puts the alignment restrictions on physical address
1763 where kernel is loaded and run from. Kernel is compiled for an
1764 address which meets above alignment restriction.
1766 If bootloader loads the kernel at a non-aligned address and
1767 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1768 address aligned to above value and run from there.
1770 If bootloader loads the kernel at a non-aligned address and
1771 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1772 load address and decompress itself to the address it has been
1773 compiled for and run from there. The address for which kernel is
1774 compiled already meets above alignment restrictions. Hence the
1775 end result is that kernel runs from a physical address meeting
1776 above alignment restrictions.
1778 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1779 this value must be a multiple of 0x200000.
1781 Don't change this unless you know what you are doing.
1784 bool "Support for hot-pluggable CPUs"
1787 Say Y here to allow turning CPUs off and on. CPUs can be
1788 controlled through /sys/devices/system/cpu.
1789 ( Note: power management support will enable this option
1790 automatically on SMP systems. )
1791 Say N if you want to disable CPU hotplug.
1793 config BOOTPARAM_HOTPLUG_CPU0
1794 bool "Set default setting of cpu0_hotpluggable"
1796 depends on HOTPLUG_CPU
1798 Set whether default state of cpu0_hotpluggable is on or off.
1800 Say Y here to enable CPU0 hotplug by default. If this switch
1801 is turned on, there is no need to give cpu0_hotplug kernel
1802 parameter and the CPU0 hotplug feature is enabled by default.
1804 Please note: there are two known CPU0 dependencies if you want
1805 to enable the CPU0 hotplug feature either by this switch or by
1806 cpu0_hotplug kernel parameter.
1808 First, resume from hibernate or suspend always starts from CPU0.
1809 So hibernate and suspend are prevented if CPU0 is offline.
1811 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1812 offline if any interrupt can not migrate out of CPU0. There may
1813 be other CPU0 dependencies.
1815 Please make sure the dependencies are under your control before
1816 you enable this feature.
1818 Say N if you don't want to enable CPU0 hotplug feature by default.
1819 You still can enable the CPU0 hotplug feature at boot by kernel
1820 parameter cpu0_hotplug.
1822 config DEBUG_HOTPLUG_CPU0
1824 prompt "Debug CPU0 hotplug"
1825 depends on HOTPLUG_CPU
1827 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1828 soon as possible and boots up userspace with CPU0 offlined. User
1829 can online CPU0 back after boot time.
1831 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1832 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1833 compilation or giving cpu0_hotplug kernel parameter at boot.
1839 prompt "Compat VDSO support"
1840 depends on X86_32 || IA32_EMULATION
1842 Map the 32-bit VDSO to the predictable old-style address too.
1844 Say N here if you are running a sufficiently recent glibc
1845 version (2.3.3 or later), to remove the high-mapped
1846 VDSO mapping and to exclusively use the randomized VDSO.
1851 bool "Built-in kernel command line"
1853 Allow for specifying boot arguments to the kernel at
1854 build time. On some systems (e.g. embedded ones), it is
1855 necessary or convenient to provide some or all of the
1856 kernel boot arguments with the kernel itself (that is,
1857 to not rely on the boot loader to provide them.)
1859 To compile command line arguments into the kernel,
1860 set this option to 'Y', then fill in the
1861 the boot arguments in CONFIG_CMDLINE.
1863 Systems with fully functional boot loaders (i.e. non-embedded)
1864 should leave this option set to 'N'.
1867 string "Built-in kernel command string"
1868 depends on CMDLINE_BOOL
1871 Enter arguments here that should be compiled into the kernel
1872 image and used at boot time. If the boot loader provides a
1873 command line at boot time, it is appended to this string to
1874 form the full kernel command line, when the system boots.
1876 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1877 change this behavior.
1879 In most cases, the command line (whether built-in or provided
1880 by the boot loader) should specify the device for the root
1883 config CMDLINE_OVERRIDE
1884 bool "Built-in command line overrides boot loader arguments"
1885 depends on CMDLINE_BOOL
1887 Set this option to 'Y' to have the kernel ignore the boot loader
1888 command line, and use ONLY the built-in command line.
1890 This is used to work around broken boot loaders. This should
1891 be set to 'N' under normal conditions.
1895 config ARCH_ENABLE_MEMORY_HOTPLUG
1897 depends on X86_64 || (X86_32 && HIGHMEM)
1899 config ARCH_ENABLE_MEMORY_HOTREMOVE
1901 depends on MEMORY_HOTPLUG
1903 config USE_PERCPU_NUMA_NODE_ID
1907 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1909 depends on X86_64 || X86_PAE
1911 menu "Power management and ACPI options"
1913 config ARCH_HIBERNATION_HEADER
1915 depends on X86_64 && HIBERNATION
1917 source "kernel/power/Kconfig"
1919 source "drivers/acpi/Kconfig"
1921 source "drivers/sfi/Kconfig"
1928 tristate "APM (Advanced Power Management) BIOS support"
1929 depends on X86_32 && PM_SLEEP
1931 APM is a BIOS specification for saving power using several different
1932 techniques. This is mostly useful for battery powered laptops with
1933 APM compliant BIOSes. If you say Y here, the system time will be
1934 reset after a RESUME operation, the /proc/apm device will provide
1935 battery status information, and user-space programs will receive
1936 notification of APM "events" (e.g. battery status change).
1938 If you select "Y" here, you can disable actual use of the APM
1939 BIOS by passing the "apm=off" option to the kernel at boot time.
1941 Note that the APM support is almost completely disabled for
1942 machines with more than one CPU.
1944 In order to use APM, you will need supporting software. For location
1945 and more information, read <file:Documentation/power/apm-acpi.txt>
1946 and the Battery Powered Linux mini-HOWTO, available from
1947 <http://www.tldp.org/docs.html#howto>.
1949 This driver does not spin down disk drives (see the hdparm(8)
1950 manpage ("man 8 hdparm") for that), and it doesn't turn off
1951 VESA-compliant "green" monitors.
1953 This driver does not support the TI 4000M TravelMate and the ACER
1954 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1955 desktop machines also don't have compliant BIOSes, and this driver
1956 may cause those machines to panic during the boot phase.
1958 Generally, if you don't have a battery in your machine, there isn't
1959 much point in using this driver and you should say N. If you get
1960 random kernel OOPSes or reboots that don't seem to be related to
1961 anything, try disabling/enabling this option (or disabling/enabling
1964 Some other things you should try when experiencing seemingly random,
1967 1) make sure that you have enough swap space and that it is
1969 2) pass the "no-hlt" option to the kernel
1970 3) switch on floating point emulation in the kernel and pass
1971 the "no387" option to the kernel
1972 4) pass the "floppy=nodma" option to the kernel
1973 5) pass the "mem=4M" option to the kernel (thereby disabling
1974 all but the first 4 MB of RAM)
1975 6) make sure that the CPU is not over clocked.
1976 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1977 8) disable the cache from your BIOS settings
1978 9) install a fan for the video card or exchange video RAM
1979 10) install a better fan for the CPU
1980 11) exchange RAM chips
1981 12) exchange the motherboard.
1983 To compile this driver as a module, choose M here: the
1984 module will be called apm.
1988 config APM_IGNORE_USER_SUSPEND
1989 bool "Ignore USER SUSPEND"
1991 This option will ignore USER SUSPEND requests. On machines with a
1992 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1993 series notebooks, it is necessary to say Y because of a BIOS bug.
1995 config APM_DO_ENABLE
1996 bool "Enable PM at boot time"
1998 Enable APM features at boot time. From page 36 of the APM BIOS
1999 specification: "When disabled, the APM BIOS does not automatically
2000 power manage devices, enter the Standby State, enter the Suspend
2001 State, or take power saving steps in response to CPU Idle calls."
2002 This driver will make CPU Idle calls when Linux is idle (unless this
2003 feature is turned off -- see "Do CPU IDLE calls", below). This
2004 should always save battery power, but more complicated APM features
2005 will be dependent on your BIOS implementation. You may need to turn
2006 this option off if your computer hangs at boot time when using APM
2007 support, or if it beeps continuously instead of suspending. Turn
2008 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2009 T400CDT. This is off by default since most machines do fine without
2014 bool "Make CPU Idle calls when idle"
2016 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2017 On some machines, this can activate improved power savings, such as
2018 a slowed CPU clock rate, when the machine is idle. These idle calls
2019 are made after the idle loop has run for some length of time (e.g.,
2020 333 mS). On some machines, this will cause a hang at boot time or
2021 whenever the CPU becomes idle. (On machines with more than one CPU,
2022 this option does nothing.)
2024 config APM_DISPLAY_BLANK
2025 bool "Enable console blanking using APM"
2027 Enable console blanking using the APM. Some laptops can use this to
2028 turn off the LCD backlight when the screen blanker of the Linux
2029 virtual console blanks the screen. Note that this is only used by
2030 the virtual console screen blanker, and won't turn off the backlight
2031 when using the X Window system. This also doesn't have anything to
2032 do with your VESA-compliant power-saving monitor. Further, this
2033 option doesn't work for all laptops -- it might not turn off your
2034 backlight at all, or it might print a lot of errors to the console,
2035 especially if you are using gpm.
2037 config APM_ALLOW_INTS
2038 bool "Allow interrupts during APM BIOS calls"
2040 Normally we disable external interrupts while we are making calls to
2041 the APM BIOS as a measure to lessen the effects of a badly behaving
2042 BIOS implementation. The BIOS should reenable interrupts if it
2043 needs to. Unfortunately, some BIOSes do not -- especially those in
2044 many of the newer IBM Thinkpads. If you experience hangs when you
2045 suspend, try setting this to Y. Otherwise, say N.
2049 source "drivers/cpufreq/Kconfig"
2051 source "drivers/cpuidle/Kconfig"
2053 source "drivers/idle/Kconfig"
2058 menu "Bus options (PCI etc.)"
2064 Find out whether you have a PCI motherboard. PCI is the name of a
2065 bus system, i.e. the way the CPU talks to the other stuff inside
2066 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2067 VESA. If you have PCI, say Y, otherwise N.
2070 prompt "PCI access mode"
2071 depends on X86_32 && PCI
2074 On PCI systems, the BIOS can be used to detect the PCI devices and
2075 determine their configuration. However, some old PCI motherboards
2076 have BIOS bugs and may crash if this is done. Also, some embedded
2077 PCI-based systems don't have any BIOS at all. Linux can also try to
2078 detect the PCI hardware directly without using the BIOS.
2080 With this option, you can specify how Linux should detect the
2081 PCI devices. If you choose "BIOS", the BIOS will be used,
2082 if you choose "Direct", the BIOS won't be used, and if you
2083 choose "MMConfig", then PCI Express MMCONFIG will be used.
2084 If you choose "Any", the kernel will try MMCONFIG, then the
2085 direct access method and falls back to the BIOS if that doesn't
2086 work. If unsure, go with the default, which is "Any".
2091 config PCI_GOMMCONFIG
2108 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2110 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2113 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2117 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2121 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2125 depends on PCI && XEN
2133 bool "Support mmconfig PCI config space access"
2134 depends on X86_64 && PCI && ACPI
2136 config PCI_CNB20LE_QUIRK
2137 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2140 Read the PCI windows out of the CNB20LE host bridge. This allows
2141 PCI hotplug to work on systems with the CNB20LE chipset which do
2144 There's no public spec for this chipset, and this functionality
2145 is known to be incomplete.
2147 You should say N unless you know you need this.
2149 source "drivers/pci/pcie/Kconfig"
2151 source "drivers/pci/Kconfig"
2153 # x86_64 have no ISA slots, but can have ISA-style DMA.
2155 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2158 Enables ISA-style DMA support for devices requiring such controllers.
2166 Find out whether you have ISA slots on your motherboard. ISA is the
2167 name of a bus system, i.e. the way the CPU talks to the other stuff
2168 inside your box. Other bus systems are PCI, EISA, MicroChannel
2169 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2170 newer boards don't support it. If you have ISA, say Y, otherwise N.
2176 The Extended Industry Standard Architecture (EISA) bus was
2177 developed as an open alternative to the IBM MicroChannel bus.
2179 The EISA bus provided some of the features of the IBM MicroChannel
2180 bus while maintaining backward compatibility with cards made for
2181 the older ISA bus. The EISA bus saw limited use between 1988 and
2182 1995 when it was made obsolete by the PCI bus.
2184 Say Y here if you are building a kernel for an EISA-based machine.
2188 source "drivers/eisa/Kconfig"
2191 tristate "NatSemi SCx200 support"
2193 This provides basic support for National Semiconductor's
2194 (now AMD's) Geode processors. The driver probes for the
2195 PCI-IDs of several on-chip devices, so its a good dependency
2196 for other scx200_* drivers.
2198 If compiled as a module, the driver is named scx200.
2200 config SCx200HR_TIMER
2201 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2205 This driver provides a clocksource built upon the on-chip
2206 27MHz high-resolution timer. Its also a workaround for
2207 NSC Geode SC-1100's buggy TSC, which loses time when the
2208 processor goes idle (as is done by the scheduler). The
2209 other workaround is idle=poll boot option.
2212 bool "One Laptop Per Child support"
2219 Add support for detecting the unique features of the OLPC
2223 bool "OLPC XO-1 Power Management"
2224 depends on OLPC && MFD_CS5535 && PM_SLEEP
2227 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2230 bool "OLPC XO-1 Real Time Clock"
2231 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2233 Add support for the XO-1 real time clock, which can be used as a
2234 programmable wakeup source.
2237 bool "OLPC XO-1 SCI extras"
2238 depends on OLPC && OLPC_XO1_PM
2244 Add support for SCI-based features of the OLPC XO-1 laptop:
2245 - EC-driven system wakeups
2249 - AC adapter status updates
2250 - Battery status updates
2252 config OLPC_XO15_SCI
2253 bool "OLPC XO-1.5 SCI extras"
2254 depends on OLPC && ACPI
2257 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2258 - EC-driven system wakeups
2259 - AC adapter status updates
2260 - Battery status updates
2263 bool "PCEngines ALIX System Support (LED setup)"
2266 This option enables system support for the PCEngines ALIX.
2267 At present this just sets up LEDs for GPIO control on
2268 ALIX2/3/6 boards. However, other system specific setup should
2271 Note: You must still enable the drivers for GPIO and LED support
2272 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2274 Note: You have to set alix.force=1 for boards with Award BIOS.
2277 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2280 This option enables system support for the Soekris Engineering net5501.
2283 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2287 This option enables system support for the Traverse Technologies GEOS.
2290 bool "Technologic Systems TS-5500 platform support"
2292 select CHECK_SIGNATURE
2296 This option enables system support for the Technologic Systems TS-5500.
2302 depends on CPU_SUP_AMD && PCI
2304 source "drivers/pcmcia/Kconfig"
2306 source "drivers/pci/hotplug/Kconfig"
2309 tristate "RapidIO support"
2313 If enabled this option will include drivers and the core
2314 infrastructure code to support RapidIO interconnect devices.
2316 source "drivers/rapidio/Kconfig"
2319 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2321 Firmwares often provide initial graphics framebuffers so the BIOS,
2322 bootloader or kernel can show basic video-output during boot for
2323 user-guidance and debugging. Historically, x86 used the VESA BIOS
2324 Extensions and EFI-framebuffers for this, which are mostly limited
2326 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2327 framebuffers so the new generic system-framebuffer drivers can be
2328 used on x86. If the framebuffer is not compatible with the generic
2329 modes, it is adverticed as fallback platform framebuffer so legacy
2330 drivers like efifb, vesafb and uvesafb can pick it up.
2331 If this option is not selected, all system framebuffers are always
2332 marked as fallback platform framebuffers as usual.
2334 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2335 not be able to pick up generic system framebuffers if this option
2336 is selected. You are highly encouraged to enable simplefb as
2337 replacement if you select this option. simplefb can correctly deal
2338 with generic system framebuffers. But you should still keep vesafb
2339 and others enabled as fallback if a system framebuffer is
2340 incompatible with simplefb.
2347 menu "Executable file formats / Emulations"
2349 source "fs/Kconfig.binfmt"
2351 config IA32_EMULATION
2352 bool "IA32 Emulation"
2355 select COMPAT_BINFMT_ELF
2358 Include code to run legacy 32-bit programs under a
2359 64-bit kernel. You should likely turn this on, unless you're
2360 100% sure that you don't have any 32-bit programs left.
2363 tristate "IA32 a.out support"
2364 depends on IA32_EMULATION
2366 Support old a.out binaries in the 32bit emulation.
2369 bool "x32 ABI for 64-bit mode"
2370 depends on X86_64 && IA32_EMULATION
2372 Include code to run binaries for the x32 native 32-bit ABI
2373 for 64-bit processors. An x32 process gets access to the
2374 full 64-bit register file and wide data path while leaving
2375 pointers at 32 bits for smaller memory footprint.
2377 You will need a recent binutils (2.22 or later) with
2378 elf32_x86_64 support enabled to compile a kernel with this
2383 depends on IA32_EMULATION || X86_X32
2384 select ARCH_WANT_OLD_COMPAT_IPC
2387 config COMPAT_FOR_U64_ALIGNMENT
2390 config SYSVIPC_COMPAT
2402 config HAVE_ATOMIC_IOMAP
2406 config X86_DEV_DMA_OPS
2408 depends on X86_64 || STA2X11
2410 config X86_DMA_REMAP
2418 To be selected by modules requiring access to the Intel OnChip System
2419 Fabric (IOSF) Sideband MailBox Interface (MBI). For MBI platforms
2422 source "net/Kconfig"
2424 source "drivers/Kconfig"
2426 source "drivers/firmware/Kconfig"
2430 source "arch/x86/Kconfig.debug"
2432 source "security/Kconfig"
2434 source "crypto/Kconfig"
2436 source "arch/x86/kvm/Kconfig"
2438 source "lib/Kconfig"
projects / platform / adaptation / renesas_rcar / renesas_kernel.git / blob