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_MIGHT_HAVE_ACPI_PDC if ACPI
25 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
26 select ARCH_MIGHT_HAVE_PC_PARPORT
27 select ARCH_MIGHT_HAVE_PC_SERIO
28 select HAVE_AOUT if X86_32
29 select HAVE_UNSTABLE_SCHED_CLOCK
30 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
31 select ARCH_SUPPORTS_INT128 if X86_64
32 select ARCH_WANTS_PROT_NUMA_PROT_NONE
35 select HAVE_PCSPKR_PLATFORM
36 select HAVE_PERF_EVENTS
37 select HAVE_IOREMAP_PROT
40 select HAVE_MEMBLOCK_NODE_MAP
41 select ARCH_DISCARD_MEMBLOCK
42 select ARCH_WANT_OPTIONAL_GPIOLIB
43 select ARCH_WANT_FRAME_POINTERS
45 select HAVE_DMA_CONTIGUOUS
46 select HAVE_KRETPROBES
47 select GENERIC_EARLY_IOREMAP
49 select HAVE_KPROBES_ON_FTRACE
50 select HAVE_FTRACE_MCOUNT_RECORD
51 select HAVE_FENTRY if X86_64
52 select HAVE_C_RECORDMCOUNT
53 select HAVE_DYNAMIC_FTRACE
54 select HAVE_DYNAMIC_FTRACE_WITH_REGS
55 select HAVE_FUNCTION_TRACER
56 select HAVE_FUNCTION_GRAPH_TRACER
57 select HAVE_FUNCTION_GRAPH_FP_TEST
58 select HAVE_SYSCALL_TRACEPOINTS
59 select SYSCTL_EXCEPTION_TRACE
62 select HAVE_ARCH_TRACEHOOK
63 select HAVE_GENERIC_DMA_COHERENT if X86_32
64 select HAVE_EFFICIENT_UNALIGNED_ACCESS
65 select USER_STACKTRACE_SUPPORT
66 select HAVE_REGS_AND_STACK_ACCESS_API
67 select HAVE_DMA_API_DEBUG
68 select HAVE_KERNEL_GZIP
69 select HAVE_KERNEL_BZIP2
70 select HAVE_KERNEL_LZMA
72 select HAVE_KERNEL_LZO
73 select HAVE_KERNEL_LZ4
74 select HAVE_HW_BREAKPOINT
75 select HAVE_MIXED_BREAKPOINTS_REGS
77 select HAVE_PERF_EVENTS_NMI
79 select HAVE_PERF_USER_STACK_DUMP
80 select HAVE_DEBUG_KMEMLEAK
82 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
83 select HAVE_CMPXCHG_LOCAL
84 select HAVE_CMPXCHG_DOUBLE
85 select HAVE_ARCH_KMEMCHECK
86 select HAVE_USER_RETURN_NOTIFIER
87 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
88 select HAVE_ARCH_JUMP_LABEL
89 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
91 select GENERIC_FIND_FIRST_BIT
92 select GENERIC_IRQ_PROBE
93 select GENERIC_PENDING_IRQ if SMP
94 select GENERIC_IRQ_SHOW
95 select GENERIC_CLOCKEVENTS_MIN_ADJUST
96 select IRQ_FORCED_THREADING
97 select HAVE_BPF_JIT if X86_64
98 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
100 select ARCH_HAVE_NMI_SAFE_CMPXCHG
102 select DCACHE_WORD_ACCESS
103 select GENERIC_SMP_IDLE_THREAD
104 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
105 select HAVE_ARCH_SECCOMP_FILTER
106 select BUILDTIME_EXTABLE_SORT
107 select GENERIC_CMOS_UPDATE
108 select HAVE_ARCH_SOFT_DIRTY if X86_64
109 select CLOCKSOURCE_WATCHDOG
110 select GENERIC_CLOCKEVENTS
111 select ARCH_CLOCKSOURCE_DATA
112 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
113 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
114 select GENERIC_TIME_VSYSCALL
115 select GENERIC_STRNCPY_FROM_USER
116 select GENERIC_STRNLEN_USER
117 select HAVE_CONTEXT_TRACKING if X86_64
118 select HAVE_IRQ_TIME_ACCOUNTING
120 select MODULES_USE_ELF_REL if X86_32
121 select MODULES_USE_ELF_RELA if X86_64
122 select CLONE_BACKWARDS if X86_32
123 select ARCH_USE_BUILTIN_BSWAP
124 select ARCH_USE_QUEUE_RWLOCK
125 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
126 select OLD_SIGACTION if X86_32
127 select COMPAT_OLD_SIGACTION if IA32_EMULATION
129 select HAVE_DEBUG_STACKOVERFLOW
130 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
131 select HAVE_CC_STACKPROTECTOR
132 select GENERIC_CPU_AUTOPROBE
133 select HAVE_ARCH_AUDITSYSCALL
134 select ARCH_SUPPORTS_ATOMIC_RMW
135 select HAVE_ACPI_APEI if ACPI
136 select HAVE_ACPI_APEI_NMI if ACPI
137 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
139 config INSTRUCTION_DECODER
141 depends on KPROBES || PERF_EVENTS || UPROBES
145 default "elf32-i386" if X86_32
146 default "elf64-x86-64" if X86_64
148 config ARCH_DEFCONFIG
150 default "arch/x86/configs/i386_defconfig" if X86_32
151 default "arch/x86/configs/x86_64_defconfig" if X86_64
153 config LOCKDEP_SUPPORT
156 config STACKTRACE_SUPPORT
159 config HAVE_LATENCYTOP_SUPPORT
168 config NEED_DMA_MAP_STATE
170 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
172 config NEED_SG_DMA_LENGTH
175 config GENERIC_ISA_DMA
177 depends on ISA_DMA_API
182 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
184 config GENERIC_BUG_RELATIVE_POINTERS
187 config GENERIC_HWEIGHT
190 config ARCH_MAY_HAVE_PC_FDC
192 depends on ISA_DMA_API
194 config RWSEM_XCHGADD_ALGORITHM
197 config GENERIC_CALIBRATE_DELAY
200 config ARCH_HAS_CPU_RELAX
203 config ARCH_HAS_CACHE_LINE_SIZE
206 config HAVE_SETUP_PER_CPU_AREA
209 config NEED_PER_CPU_EMBED_FIRST_CHUNK
212 config NEED_PER_CPU_PAGE_FIRST_CHUNK
215 config ARCH_HIBERNATION_POSSIBLE
218 config ARCH_SUSPEND_POSSIBLE
221 config ARCH_WANT_HUGE_PMD_SHARE
224 config ARCH_WANT_GENERAL_HUGETLB
235 config ARCH_SUPPORTS_OPTIMIZED_INLINING
238 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
241 config HAVE_INTEL_TXT
243 depends on INTEL_IOMMU && ACPI
247 depends on X86_32 && SMP
251 depends on X86_64 && SMP
257 config X86_32_LAZY_GS
259 depends on X86_32 && !CC_STACKPROTECTOR
261 config ARCH_HWEIGHT_CFLAGS
263 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
264 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
266 config ARCH_SUPPORTS_UPROBES
269 config FIX_EARLYCON_MEM
272 source "init/Kconfig"
273 source "kernel/Kconfig.freezer"
275 menu "Processor type and features"
278 bool "DMA memory allocation support" if EXPERT
281 DMA memory allocation support allows devices with less than 32-bit
282 addressing to allocate within the first 16MB of address space.
283 Disable if no such devices will be used.
288 bool "Symmetric multi-processing support"
290 This enables support for systems with more than one CPU. If you have
291 a system with only one CPU, say N. If you have a system with more
294 If you say N here, the kernel will run on uni- and multiprocessor
295 machines, but will use only one CPU of a multiprocessor machine. If
296 you say Y here, the kernel will run on many, but not all,
297 uniprocessor machines. On a uniprocessor machine, the kernel
298 will run faster if you say N here.
300 Note that if you say Y here and choose architecture "586" or
301 "Pentium" under "Processor family", the kernel will not work on 486
302 architectures. Similarly, multiprocessor kernels for the "PPro"
303 architecture may not work on all Pentium based boards.
305 People using multiprocessor machines who say Y here should also say
306 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
307 Management" code will be disabled if you say Y here.
309 See also <file:Documentation/x86/i386/IO-APIC.txt>,
310 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
311 <http://www.tldp.org/docs.html#howto>.
313 If you don't know what to do here, say N.
316 bool "Support x2apic"
317 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
319 This enables x2apic support on CPUs that have this feature.
321 This allows 32-bit apic IDs (so it can support very large systems),
322 and accesses the local apic via MSRs not via mmio.
324 If you don't know what to do here, say N.
327 bool "Enable MPS table" if ACPI || SFI
329 depends on X86_LOCAL_APIC
331 For old smp systems that do not have proper acpi support. Newer systems
332 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
335 bool "Support for big SMP systems with more than 8 CPUs"
336 depends on X86_32 && SMP
338 This option is needed for the systems that have more than 8 CPUs
342 depends on X86_GOLDFISH
345 config X86_EXTENDED_PLATFORM
346 bool "Support for extended (non-PC) x86 platforms"
349 If you disable this option then the kernel will only support
350 standard PC platforms. (which covers the vast majority of
353 If you enable this option then you'll be able to select support
354 for the following (non-PC) 32 bit x86 platforms:
355 Goldfish (Android emulator)
358 SGI 320/540 (Visual Workstation)
359 STA2X11-based (e.g. Northville)
360 Moorestown MID devices
362 If you have one of these systems, or if you want to build a
363 generic distribution kernel, say Y here - otherwise say N.
367 config X86_EXTENDED_PLATFORM
368 bool "Support for extended (non-PC) x86 platforms"
371 If you disable this option then the kernel will only support
372 standard PC platforms. (which covers the vast majority of
375 If you enable this option then you'll be able to select support
376 for the following (non-PC) 64 bit x86 platforms:
381 If you have one of these systems, or if you want to build a
382 generic distribution kernel, say Y here - otherwise say N.
384 # This is an alphabetically sorted list of 64 bit extended platforms
385 # Please maintain the alphabetic order if and when there are additions
387 bool "Numascale NumaChip"
389 depends on X86_EXTENDED_PLATFORM
392 depends on X86_X2APIC
393 depends on PCI_MMCONFIG
395 Adds support for Numascale NumaChip large-SMP systems. Needed to
396 enable more than ~168 cores.
397 If you don't have one of these, you should say N here.
401 select HYPERVISOR_GUEST
403 depends on X86_64 && PCI
404 depends on X86_EXTENDED_PLATFORM
407 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
408 supposed to run on these EM64T-based machines. Only choose this option
409 if you have one of these machines.
412 bool "SGI Ultraviolet"
414 depends on X86_EXTENDED_PLATFORM
416 depends on X86_X2APIC
418 This option is needed in order to support SGI Ultraviolet systems.
419 If you don't have one of these, you should say N here.
421 # Following is an alphabetically sorted list of 32 bit extended platforms
422 # Please maintain the alphabetic order if and when there are additions
425 bool "Goldfish (Virtual Platform)"
426 depends on X86_EXTENDED_PLATFORM
428 Enable support for the Goldfish virtual platform used primarily
429 for Android development. Unless you are building for the Android
430 Goldfish emulator say N here.
433 bool "CE4100 TV platform"
435 depends on PCI_GODIRECT
437 depends on X86_EXTENDED_PLATFORM
438 select X86_REBOOTFIXUPS
440 select OF_EARLY_FLATTREE
443 Select for the Intel CE media processor (CE4100) SOC.
444 This option compiles in support for the CE4100 SOC for settop
445 boxes and media devices.
448 bool "Intel MID platform support"
450 depends on X86_EXTENDED_PLATFORM
451 depends on X86_PLATFORM_DEVICES
454 depends on X86_IO_APIC
460 select MFD_INTEL_MSIC
462 Select to build a kernel capable of supporting Intel MID (Mobile
463 Internet Device) platform systems which do not have the PCI legacy
464 interfaces. If you are building for a PC class system say N here.
466 Intel MID platforms are based on an Intel processor and chipset which
467 consume less power than most of the x86 derivatives.
469 config X86_INTEL_LPSS
470 bool "Intel Low Power Subsystem Support"
475 Select to build support for Intel Low Power Subsystem such as
476 found on Intel Lynxpoint PCH. Selecting this option enables
477 things like clock tree (common clock framework) and pincontrol
478 which are needed by the LPSS peripheral drivers.
481 bool "RDC R-321x SoC"
483 depends on X86_EXTENDED_PLATFORM
485 select X86_REBOOTFIXUPS
487 This option is needed for RDC R-321x system-on-chip, also known
489 If you don't have one of these chips, you should say N here.
491 config X86_32_NON_STANDARD
492 bool "Support non-standard 32-bit SMP architectures"
493 depends on X86_32 && SMP
494 depends on X86_EXTENDED_PLATFORM
496 This option compiles in the bigsmp and STA2X11 default
497 subarchitectures. It is intended for a generic binary
498 kernel. If you select them all, kernel will probe it one by
499 one and will fallback to default.
501 # Alphabetically sorted list of Non standard 32 bit platforms
503 config X86_SUPPORTS_MEMORY_FAILURE
505 # MCE code calls memory_failure():
507 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
508 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
509 depends on X86_64 || !SPARSEMEM
510 select ARCH_SUPPORTS_MEMORY_FAILURE
513 bool "STA2X11 Companion Chip Support"
514 depends on X86_32_NON_STANDARD && PCI
515 select X86_DEV_DMA_OPS
519 select ARCH_REQUIRE_GPIOLIB
522 This adds support for boards based on the STA2X11 IO-Hub,
523 a.k.a. "ConneXt". The chip is used in place of the standard
524 PC chipset, so all "standard" peripherals are missing. If this
525 option is selected the kernel will still be able to boot on
526 standard PC machines.
529 tristate "Eurobraille/Iris poweroff module"
532 The Iris machines from EuroBraille do not have APM or ACPI support
533 to shut themselves down properly. A special I/O sequence is
534 needed to do so, which is what this module does at
537 This is only for Iris machines from EuroBraille.
541 config SCHED_OMIT_FRAME_POINTER
543 prompt "Single-depth WCHAN output"
546 Calculate simpler /proc/<PID>/wchan values. If this option
547 is disabled then wchan values will recurse back to the
548 caller function. This provides more accurate wchan values,
549 at the expense of slightly more scheduling overhead.
551 If in doubt, say "Y".
553 menuconfig HYPERVISOR_GUEST
554 bool "Linux guest support"
556 Say Y here to enable options for running Linux under various hyper-
557 visors. This option enables basic hypervisor detection and platform
560 If you say N, all options in this submenu will be skipped and
561 disabled, and Linux guest support won't be built in.
566 bool "Enable paravirtualization code"
568 This changes the kernel so it can modify itself when it is run
569 under a hypervisor, potentially improving performance significantly
570 over full virtualization. However, when run without a hypervisor
571 the kernel is theoretically slower and slightly larger.
573 config PARAVIRT_DEBUG
574 bool "paravirt-ops debugging"
575 depends on PARAVIRT && DEBUG_KERNEL
577 Enable to debug paravirt_ops internals. Specifically, BUG if
578 a paravirt_op is missing when it is called.
580 config PARAVIRT_SPINLOCKS
581 bool "Paravirtualization layer for spinlocks"
582 depends on PARAVIRT && SMP
583 select UNINLINE_SPIN_UNLOCK
585 Paravirtualized spinlocks allow a pvops backend to replace the
586 spinlock implementation with something virtualization-friendly
587 (for example, block the virtual CPU rather than spinning).
589 It has a minimal impact on native kernels and gives a nice performance
590 benefit on paravirtualized KVM / Xen kernels.
592 If you are unsure how to answer this question, answer Y.
594 source "arch/x86/xen/Kconfig"
597 bool "KVM Guest support (including kvmclock)"
599 select PARAVIRT_CLOCK
602 This option enables various optimizations for running under the KVM
603 hypervisor. It includes a paravirtualized clock, so that instead
604 of relying on a PIT (or probably other) emulation by the
605 underlying device model, the host provides the guest with
606 timing infrastructure such as time of day, and system time
609 bool "Enable debug information for KVM Guests in debugfs"
610 depends on KVM_GUEST && DEBUG_FS
613 This option enables collection of various statistics for KVM guest.
614 Statistics are displayed in debugfs filesystem. Enabling this option
615 may incur significant overhead.
617 source "arch/x86/lguest/Kconfig"
619 config PARAVIRT_TIME_ACCOUNTING
620 bool "Paravirtual steal time accounting"
624 Select this option to enable fine granularity task steal time
625 accounting. Time spent executing other tasks in parallel with
626 the current vCPU is discounted from the vCPU power. To account for
627 that, there can be a small performance impact.
629 If in doubt, say N here.
631 config PARAVIRT_CLOCK
634 endif #HYPERVISOR_GUEST
642 This option adds a kernel parameter 'memtest', which allows memtest
644 memtest=0, mean disabled; -- default
645 memtest=1, mean do 1 test pattern;
647 memtest=4, mean do 4 test patterns.
648 If you are unsure how to answer this question, answer N.
650 source "arch/x86/Kconfig.cpu"
654 prompt "HPET Timer Support" if X86_32
656 Use the IA-PC HPET (High Precision Event Timer) to manage
657 time in preference to the PIT and RTC, if a HPET is
659 HPET is the next generation timer replacing legacy 8254s.
660 The HPET provides a stable time base on SMP
661 systems, unlike the TSC, but it is more expensive to access,
662 as it is off-chip. You can find the HPET spec at
663 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
665 You can safely choose Y here. However, HPET will only be
666 activated if the platform and the BIOS support this feature.
667 Otherwise the 8254 will be used for timing services.
669 Choose N to continue using the legacy 8254 timer.
671 config HPET_EMULATE_RTC
673 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
676 def_bool y if X86_INTEL_MID
677 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
679 depends on X86_INTEL_MID && SFI
681 APB timer is the replacement for 8254, HPET on X86 MID platforms.
682 The APBT provides a stable time base on SMP
683 systems, unlike the TSC, but it is more expensive to access,
684 as it is off-chip. APB timers are always running regardless of CPU
685 C states, they are used as per CPU clockevent device when possible.
687 # Mark as expert because too many people got it wrong.
688 # The code disables itself when not needed.
691 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
692 bool "Enable DMI scanning" if EXPERT
694 Enabled scanning of DMI to identify machine quirks. Say Y
695 here unless you have verified that your setup is not
696 affected by entries in the DMI blacklist. Required by PNP
700 bool "Old AMD GART IOMMU support"
702 depends on X86_64 && PCI && AMD_NB
704 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
705 GART based hardware IOMMUs.
707 The GART supports full DMA access for devices with 32-bit access
708 limitations, on systems with more than 3 GB. This is usually needed
709 for USB, sound, many IDE/SATA chipsets and some other devices.
711 Newer systems typically have a modern AMD IOMMU, supported via
712 the CONFIG_AMD_IOMMU=y config option.
714 In normal configurations this driver is only active when needed:
715 there's more than 3 GB of memory and the system contains a
716 32-bit limited device.
721 bool "IBM Calgary IOMMU support"
723 depends on X86_64 && PCI
725 Support for hardware IOMMUs in IBM's xSeries x366 and x460
726 systems. Needed to run systems with more than 3GB of memory
727 properly with 32-bit PCI devices that do not support DAC
728 (Double Address Cycle). Calgary also supports bus level
729 isolation, where all DMAs pass through the IOMMU. This
730 prevents them from going anywhere except their intended
731 destination. This catches hard-to-find kernel bugs and
732 mis-behaving drivers and devices that do not use the DMA-API
733 properly to set up their DMA buffers. The IOMMU can be
734 turned off at boot time with the iommu=off parameter.
735 Normally the kernel will make the right choice by itself.
738 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
740 prompt "Should Calgary be enabled by default?"
741 depends on CALGARY_IOMMU
743 Should Calgary be enabled by default? if you choose 'y', Calgary
744 will be used (if it exists). If you choose 'n', Calgary will not be
745 used even if it exists. If you choose 'n' and would like to use
746 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
749 # need this always selected by IOMMU for the VIA workaround
753 Support for software bounce buffers used on x86-64 systems
754 which don't have a hardware IOMMU. Using this PCI devices
755 which can only access 32-bits of memory can be used on systems
756 with more than 3 GB of memory.
761 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
764 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
765 depends on X86_64 && SMP && DEBUG_KERNEL
766 select CPUMASK_OFFSTACK
768 Enable maximum number of CPUS and NUMA Nodes for this architecture.
772 int "Maximum number of CPUs" if SMP && !MAXSMP
773 range 2 8 if SMP && X86_32 && !X86_BIGSMP
774 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
775 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
777 default "8192" if MAXSMP
778 default "32" if SMP && X86_BIGSMP
781 This allows you to specify the maximum number of CPUs which this
782 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
783 supported value is 4096, otherwise the maximum value is 512. The
784 minimum value which makes sense is 2.
786 This is purely to save memory - each supported CPU adds
787 approximately eight kilobytes to the kernel image.
790 bool "SMT (Hyperthreading) scheduler support"
793 SMT scheduler support improves the CPU scheduler's decision making
794 when dealing with Intel Pentium 4 chips with HyperThreading at a
795 cost of slightly increased overhead in some places. If unsure say
800 prompt "Multi-core scheduler support"
803 Multi-core scheduler support improves the CPU scheduler's decision
804 making when dealing with multi-core CPU chips at a cost of slightly
805 increased overhead in some places. If unsure say N here.
807 source "kernel/Kconfig.preempt"
810 bool "Local APIC support on uniprocessors"
811 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
813 A local APIC (Advanced Programmable Interrupt Controller) is an
814 integrated interrupt controller in the CPU. If you have a single-CPU
815 system which has a processor with a local APIC, you can say Y here to
816 enable and use it. If you say Y here even though your machine doesn't
817 have a local APIC, then the kernel will still run with no slowdown at
818 all. The local APIC supports CPU-generated self-interrupts (timer,
819 performance counters), and the NMI watchdog which detects hard
823 bool "IO-APIC support on uniprocessors"
824 depends on X86_UP_APIC
826 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
827 SMP-capable replacement for PC-style interrupt controllers. Most
828 SMP systems and many recent uniprocessor systems have one.
830 If you have a single-CPU system with an IO-APIC, you can say Y here
831 to use it. If you say Y here even though your machine doesn't have
832 an IO-APIC, then the kernel will still run with no slowdown at all.
834 config X86_LOCAL_APIC
836 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
840 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
841 select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
843 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
844 bool "Reroute for broken boot IRQs"
845 depends on X86_IO_APIC
847 This option enables a workaround that fixes a source of
848 spurious interrupts. This is recommended when threaded
849 interrupt handling is used on systems where the generation of
850 superfluous "boot interrupts" cannot be disabled.
852 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
853 entry in the chipset's IO-APIC is masked (as, e.g. the RT
854 kernel does during interrupt handling). On chipsets where this
855 boot IRQ generation cannot be disabled, this workaround keeps
856 the original IRQ line masked so that only the equivalent "boot
857 IRQ" is delivered to the CPUs. The workaround also tells the
858 kernel to set up the IRQ handler on the boot IRQ line. In this
859 way only one interrupt is delivered to the kernel. Otherwise
860 the spurious second interrupt may cause the kernel to bring
861 down (vital) interrupt lines.
863 Only affects "broken" chipsets. Interrupt sharing may be
864 increased on these systems.
867 bool "Machine Check / overheating reporting"
870 Machine Check support allows the processor to notify the
871 kernel if it detects a problem (e.g. overheating, data corruption).
872 The action the kernel takes depends on the severity of the problem,
873 ranging from warning messages to halting the machine.
877 prompt "Intel MCE features"
878 depends on X86_MCE && X86_LOCAL_APIC
880 Additional support for intel specific MCE features such as
885 prompt "AMD MCE features"
886 depends on X86_MCE && X86_LOCAL_APIC
888 Additional support for AMD specific MCE features such as
889 the DRAM Error Threshold.
891 config X86_ANCIENT_MCE
892 bool "Support for old Pentium 5 / WinChip machine checks"
893 depends on X86_32 && X86_MCE
895 Include support for machine check handling on old Pentium 5 or WinChip
896 systems. These typically need to be enabled explicitly on the command
899 config X86_MCE_THRESHOLD
900 depends on X86_MCE_AMD || X86_MCE_INTEL
903 config X86_MCE_INJECT
905 tristate "Machine check injector support"
907 Provide support for injecting machine checks for testing purposes.
908 If you don't know what a machine check is and you don't do kernel
909 QA it is safe to say n.
911 config X86_THERMAL_VECTOR
913 depends on X86_MCE_INTEL
916 bool "Enable VM86 support" if EXPERT
920 This option is required by programs like DOSEMU to run
921 16-bit real mode legacy code on x86 processors. It also may
922 be needed by software like XFree86 to initialize some video
923 cards via BIOS. Disabling this option saves about 6K.
926 bool "Enable support for 16-bit segments" if EXPERT
929 This option is required by programs like Wine to run 16-bit
930 protected mode legacy code on x86 processors. Disabling
931 this option saves about 300 bytes on i386, or around 6K text
932 plus 16K runtime memory on x86-64,
936 depends on X86_16BIT && X86_32
940 depends on X86_16BIT && X86_64
943 tristate "Toshiba Laptop support"
946 This adds a driver to safely access the System Management Mode of
947 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
948 not work on models with a Phoenix BIOS. The System Management Mode
949 is used to set the BIOS and power saving options on Toshiba portables.
951 For information on utilities to make use of this driver see the
952 Toshiba Linux utilities web site at:
953 <http://www.buzzard.org.uk/toshiba/>.
955 Say Y if you intend to run this kernel on a Toshiba portable.
959 tristate "Dell laptop support"
962 This adds a driver to safely access the System Management Mode
963 of the CPU on the Dell Inspiron 8000. The System Management Mode
964 is used to read cpu temperature and cooling fan status and to
965 control the fans on the I8K portables.
967 This driver has been tested only on the Inspiron 8000 but it may
968 also work with other Dell laptops. You can force loading on other
969 models by passing the parameter `force=1' to the module. Use at
972 For information on utilities to make use of this driver see the
973 I8K Linux utilities web site at:
974 <http://people.debian.org/~dz/i8k/>
976 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
979 config X86_REBOOTFIXUPS
980 bool "Enable X86 board specific fixups for reboot"
983 This enables chipset and/or board specific fixups to be done
984 in order to get reboot to work correctly. This is only needed on
985 some combinations of hardware and BIOS. The symptom, for which
986 this config is intended, is when reboot ends with a stalled/hung
989 Currently, the only fixup is for the Geode machines using
990 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
992 Say Y if you want to enable the fixup. Currently, it's safe to
993 enable this option even if you don't need it.
997 tristate "CPU microcode loading support"
998 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1002 If you say Y here, you will be able to update the microcode on
1003 certain Intel and AMD processors. The Intel support is for the
1004 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1005 Xeon etc. The AMD support is for families 0x10 and later. You will
1006 obviously need the actual microcode binary data itself which is not
1007 shipped with the Linux kernel.
1009 This option selects the general module only, you need to select
1010 at least one vendor specific module as well.
1012 To compile this driver as a module, choose M here: the module
1013 will be called microcode.
1015 config MICROCODE_INTEL
1016 bool "Intel microcode loading support"
1017 depends on MICROCODE
1021 This options enables microcode patch loading support for Intel
1024 For the current Intel microcode data package go to
1025 <https://downloadcenter.intel.com> and search for
1026 'Linux Processor Microcode Data File'.
1028 config MICROCODE_AMD
1029 bool "AMD microcode loading support"
1030 depends on MICROCODE
1033 If you select this option, microcode patch loading support for AMD
1034 processors will be enabled.
1036 config MICROCODE_OLD_INTERFACE
1038 depends on MICROCODE
1040 config MICROCODE_INTEL_EARLY
1043 config MICROCODE_AMD_EARLY
1046 config MICROCODE_EARLY
1047 bool "Early load microcode"
1048 depends on MICROCODE=y && BLK_DEV_INITRD
1049 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1050 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1053 This option provides functionality to read additional microcode data
1054 at the beginning of initrd image. The data tells kernel to load
1055 microcode to CPU's as early as possible. No functional change if no
1056 microcode data is glued to the initrd, therefore it's safe to say Y.
1059 tristate "/dev/cpu/*/msr - Model-specific register support"
1061 This device gives privileged processes access to the x86
1062 Model-Specific Registers (MSRs). It is a character device with
1063 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1064 MSR accesses are directed to a specific CPU on multi-processor
1068 tristate "/dev/cpu/*/cpuid - CPU information support"
1070 This device gives processes access to the x86 CPUID instruction to
1071 be executed on a specific processor. It is a character device
1072 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1076 prompt "High Memory Support"
1083 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1084 However, the address space of 32-bit x86 processors is only 4
1085 Gigabytes large. That means that, if you have a large amount of
1086 physical memory, not all of it can be "permanently mapped" by the
1087 kernel. The physical memory that's not permanently mapped is called
1090 If you are compiling a kernel which will never run on a machine with
1091 more than 1 Gigabyte total physical RAM, answer "off" here (default
1092 choice and suitable for most users). This will result in a "3GB/1GB"
1093 split: 3GB are mapped so that each process sees a 3GB virtual memory
1094 space and the remaining part of the 4GB virtual memory space is used
1095 by the kernel to permanently map as much physical memory as
1098 If the machine has between 1 and 4 Gigabytes physical RAM, then
1101 If more than 4 Gigabytes is used then answer "64GB" here. This
1102 selection turns Intel PAE (Physical Address Extension) mode on.
1103 PAE implements 3-level paging on IA32 processors. PAE is fully
1104 supported by Linux, PAE mode is implemented on all recent Intel
1105 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1106 then the kernel will not boot on CPUs that don't support PAE!
1108 The actual amount of total physical memory will either be
1109 auto detected or can be forced by using a kernel command line option
1110 such as "mem=256M". (Try "man bootparam" or see the documentation of
1111 your boot loader (lilo or loadlin) about how to pass options to the
1112 kernel at boot time.)
1114 If unsure, say "off".
1119 Select this if you have a 32-bit processor and between 1 and 4
1120 gigabytes of physical RAM.
1127 Select this if you have a 32-bit processor and more than 4
1128 gigabytes of physical RAM.
1133 prompt "Memory split" if EXPERT
1137 Select the desired split between kernel and user memory.
1139 If the address range available to the kernel is less than the
1140 physical memory installed, the remaining memory will be available
1141 as "high memory". Accessing high memory is a little more costly
1142 than low memory, as it needs to be mapped into the kernel first.
1143 Note that increasing the kernel address space limits the range
1144 available to user programs, making the address space there
1145 tighter. Selecting anything other than the default 3G/1G split
1146 will also likely make your kernel incompatible with binary-only
1149 If you are not absolutely sure what you are doing, leave this
1153 bool "3G/1G user/kernel split"
1154 config VMSPLIT_3G_OPT
1156 bool "3G/1G user/kernel split (for full 1G low memory)"
1158 bool "2G/2G user/kernel split"
1159 config VMSPLIT_2G_OPT
1161 bool "2G/2G user/kernel split (for full 2G low memory)"
1163 bool "1G/3G user/kernel split"
1168 default 0xB0000000 if VMSPLIT_3G_OPT
1169 default 0x80000000 if VMSPLIT_2G
1170 default 0x78000000 if VMSPLIT_2G_OPT
1171 default 0x40000000 if VMSPLIT_1G
1177 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1180 bool "PAE (Physical Address Extension) Support"
1181 depends on X86_32 && !HIGHMEM4G
1183 PAE is required for NX support, and furthermore enables
1184 larger swapspace support for non-overcommit purposes. It
1185 has the cost of more pagetable lookup overhead, and also
1186 consumes more pagetable space per process.
1188 config ARCH_PHYS_ADDR_T_64BIT
1190 depends on X86_64 || X86_PAE
1192 config ARCH_DMA_ADDR_T_64BIT
1194 depends on X86_64 || HIGHMEM64G
1196 config DIRECT_GBPAGES
1197 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1201 Allow the kernel linear mapping to use 1GB pages on CPUs that
1202 support it. This can improve the kernel's performance a tiny bit by
1203 reducing TLB pressure. If in doubt, say "Y".
1205 # Common NUMA Features
1207 bool "Numa Memory Allocation and Scheduler Support"
1209 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1210 default y if X86_BIGSMP
1212 Enable NUMA (Non Uniform Memory Access) support.
1214 The kernel will try to allocate memory used by a CPU on the
1215 local memory controller of the CPU and add some more
1216 NUMA awareness to the kernel.
1218 For 64-bit this is recommended if the system is Intel Core i7
1219 (or later), AMD Opteron, or EM64T NUMA.
1221 For 32-bit this is only needed if you boot a 32-bit
1222 kernel on a 64-bit NUMA platform.
1224 Otherwise, you should say N.
1228 prompt "Old style AMD Opteron NUMA detection"
1229 depends on X86_64 && NUMA && PCI
1231 Enable AMD NUMA node topology detection. You should say Y here if
1232 you have a multi processor AMD system. This uses an old method to
1233 read the NUMA configuration directly from the builtin Northbridge
1234 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1235 which also takes priority if both are compiled in.
1237 config X86_64_ACPI_NUMA
1239 prompt "ACPI NUMA detection"
1240 depends on X86_64 && NUMA && ACPI && PCI
1243 Enable ACPI SRAT based node topology detection.
1245 # Some NUMA nodes have memory ranges that span
1246 # other nodes. Even though a pfn is valid and
1247 # between a node's start and end pfns, it may not
1248 # reside on that node. See memmap_init_zone()
1250 config NODES_SPAN_OTHER_NODES
1252 depends on X86_64_ACPI_NUMA
1255 bool "NUMA emulation"
1258 Enable NUMA emulation. A flat machine will be split
1259 into virtual nodes when booted with "numa=fake=N", where N is the
1260 number of nodes. This is only useful for debugging.
1263 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1265 default "10" if MAXSMP
1266 default "6" if X86_64
1268 depends on NEED_MULTIPLE_NODES
1270 Specify the maximum number of NUMA Nodes available on the target
1271 system. Increases memory reserved to accommodate various tables.
1273 config ARCH_HAVE_MEMORY_PRESENT
1275 depends on X86_32 && DISCONTIGMEM
1277 config NEED_NODE_MEMMAP_SIZE
1279 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1281 config ARCH_FLATMEM_ENABLE
1283 depends on X86_32 && !NUMA
1285 config ARCH_DISCONTIGMEM_ENABLE
1287 depends on NUMA && X86_32
1289 config ARCH_DISCONTIGMEM_DEFAULT
1291 depends on NUMA && X86_32
1293 config ARCH_SPARSEMEM_ENABLE
1295 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1296 select SPARSEMEM_STATIC if X86_32
1297 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1299 config ARCH_SPARSEMEM_DEFAULT
1303 config ARCH_SELECT_MEMORY_MODEL
1305 depends on ARCH_SPARSEMEM_ENABLE
1307 config ARCH_MEMORY_PROBE
1308 bool "Enable sysfs memory/probe interface"
1309 depends on X86_64 && MEMORY_HOTPLUG
1311 This option enables a sysfs memory/probe interface for testing.
1312 See Documentation/memory-hotplug.txt for more information.
1313 If you are unsure how to answer this question, answer N.
1315 config ARCH_PROC_KCORE_TEXT
1317 depends on X86_64 && PROC_KCORE
1319 config ILLEGAL_POINTER_VALUE
1322 default 0xdead000000000000 if X86_64
1327 bool "Allocate 3rd-level pagetables from highmem"
1330 The VM uses one page table entry for each page of physical memory.
1331 For systems with a lot of RAM, this can be wasteful of precious
1332 low memory. Setting this option will put user-space page table
1333 entries in high memory.
1335 config X86_CHECK_BIOS_CORRUPTION
1336 bool "Check for low memory corruption"
1338 Periodically check for memory corruption in low memory, which
1339 is suspected to be caused by BIOS. Even when enabled in the
1340 configuration, it is disabled at runtime. Enable it by
1341 setting "memory_corruption_check=1" on the kernel command
1342 line. By default it scans the low 64k of memory every 60
1343 seconds; see the memory_corruption_check_size and
1344 memory_corruption_check_period parameters in
1345 Documentation/kernel-parameters.txt to adjust this.
1347 When enabled with the default parameters, this option has
1348 almost no overhead, as it reserves a relatively small amount
1349 of memory and scans it infrequently. It both detects corruption
1350 and prevents it from affecting the running system.
1352 It is, however, intended as a diagnostic tool; if repeatable
1353 BIOS-originated corruption always affects the same memory,
1354 you can use memmap= to prevent the kernel from using that
1357 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1358 bool "Set the default setting of memory_corruption_check"
1359 depends on X86_CHECK_BIOS_CORRUPTION
1362 Set whether the default state of memory_corruption_check is
1365 config X86_RESERVE_LOW
1366 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1370 Specify the amount of low memory to reserve for the BIOS.
1372 The first page contains BIOS data structures that the kernel
1373 must not use, so that page must always be reserved.
1375 By default we reserve the first 64K of physical RAM, as a
1376 number of BIOSes are known to corrupt that memory range
1377 during events such as suspend/resume or monitor cable
1378 insertion, so it must not be used by the kernel.
1380 You can set this to 4 if you are absolutely sure that you
1381 trust the BIOS to get all its memory reservations and usages
1382 right. If you know your BIOS have problems beyond the
1383 default 64K area, you can set this to 640 to avoid using the
1384 entire low memory range.
1386 If you have doubts about the BIOS (e.g. suspend/resume does
1387 not work or there's kernel crashes after certain hardware
1388 hotplug events) then you might want to enable
1389 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1390 typical corruption patterns.
1392 Leave this to the default value of 64 if you are unsure.
1394 config MATH_EMULATION
1396 prompt "Math emulation" if X86_32
1398 Linux can emulate a math coprocessor (used for floating point
1399 operations) if you don't have one. 486DX and Pentium processors have
1400 a math coprocessor built in, 486SX and 386 do not, unless you added
1401 a 487DX or 387, respectively. (The messages during boot time can
1402 give you some hints here ["man dmesg"].) Everyone needs either a
1403 coprocessor or this emulation.
1405 If you don't have a math coprocessor, you need to say Y here; if you
1406 say Y here even though you have a coprocessor, the coprocessor will
1407 be used nevertheless. (This behavior can be changed with the kernel
1408 command line option "no387", which comes handy if your coprocessor
1409 is broken. Try "man bootparam" or see the documentation of your boot
1410 loader (lilo or loadlin) about how to pass options to the kernel at
1411 boot time.) This means that it is a good idea to say Y here if you
1412 intend to use this kernel on different machines.
1414 More information about the internals of the Linux math coprocessor
1415 emulation can be found in <file:arch/x86/math-emu/README>.
1417 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1418 kernel, it won't hurt.
1422 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1424 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1425 the Memory Type Range Registers (MTRRs) may be used to control
1426 processor access to memory ranges. This is most useful if you have
1427 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1428 allows bus write transfers to be combined into a larger transfer
1429 before bursting over the PCI/AGP bus. This can increase performance
1430 of image write operations 2.5 times or more. Saying Y here creates a
1431 /proc/mtrr file which may be used to manipulate your processor's
1432 MTRRs. Typically the X server should use this.
1434 This code has a reasonably generic interface so that similar
1435 control registers on other processors can be easily supported
1438 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1439 Registers (ARRs) which provide a similar functionality to MTRRs. For
1440 these, the ARRs are used to emulate the MTRRs.
1441 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1442 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1443 write-combining. All of these processors are supported by this code
1444 and it makes sense to say Y here if you have one of them.
1446 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1447 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1448 can lead to all sorts of problems, so it's good to say Y here.
1450 You can safely say Y even if your machine doesn't have MTRRs, you'll
1451 just add about 9 KB to your kernel.
1453 See <file:Documentation/x86/mtrr.txt> for more information.
1455 config MTRR_SANITIZER
1457 prompt "MTRR cleanup support"
1460 Convert MTRR layout from continuous to discrete, so X drivers can
1461 add writeback entries.
1463 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1464 The largest mtrr entry size for a continuous block can be set with
1469 config MTRR_SANITIZER_ENABLE_DEFAULT
1470 int "MTRR cleanup enable value (0-1)"
1473 depends on MTRR_SANITIZER
1475 Enable mtrr cleanup default value
1477 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1478 int "MTRR cleanup spare reg num (0-7)"
1481 depends on MTRR_SANITIZER
1483 mtrr cleanup spare entries default, it can be changed via
1484 mtrr_spare_reg_nr=N on the kernel command line.
1488 prompt "x86 PAT support" if EXPERT
1491 Use PAT attributes to setup page level cache control.
1493 PATs are the modern equivalents of MTRRs and are much more
1494 flexible than MTRRs.
1496 Say N here if you see bootup problems (boot crash, boot hang,
1497 spontaneous reboots) or a non-working video driver.
1501 config ARCH_USES_PG_UNCACHED
1507 prompt "x86 architectural random number generator" if EXPERT
1509 Enable the x86 architectural RDRAND instruction
1510 (Intel Bull Mountain technology) to generate random numbers.
1511 If supported, this is a high bandwidth, cryptographically
1512 secure hardware random number generator.
1516 prompt "Supervisor Mode Access Prevention" if EXPERT
1518 Supervisor Mode Access Prevention (SMAP) is a security
1519 feature in newer Intel processors. There is a small
1520 performance cost if this enabled and turned on; there is
1521 also a small increase in the kernel size if this is enabled.
1526 bool "EFI runtime service support"
1529 select EFI_RUNTIME_WRAPPERS
1531 This enables the kernel to use EFI runtime services that are
1532 available (such as the EFI variable services).
1534 This option is only useful on systems that have EFI firmware.
1535 In addition, you should use the latest ELILO loader available
1536 at <http://elilo.sourceforge.net> in order to take advantage
1537 of EFI runtime services. However, even with this option, the
1538 resultant kernel should continue to boot on existing non-EFI
1542 bool "EFI stub support"
1545 This kernel feature allows a bzImage to be loaded directly
1546 by EFI firmware without the use of a bootloader.
1548 See Documentation/efi-stub.txt for more information.
1551 bool "EFI mixed-mode support"
1552 depends on EFI_STUB && X86_64
1554 Enabling this feature allows a 64-bit kernel to be booted
1555 on a 32-bit firmware, provided that your CPU supports 64-bit
1558 Note that it is not possible to boot a mixed-mode enabled
1559 kernel via the EFI boot stub - a bootloader that supports
1560 the EFI handover protocol must be used.
1566 prompt "Enable seccomp to safely compute untrusted bytecode"
1568 This kernel feature is useful for number crunching applications
1569 that may need to compute untrusted bytecode during their
1570 execution. By using pipes or other transports made available to
1571 the process as file descriptors supporting the read/write
1572 syscalls, it's possible to isolate those applications in
1573 their own address space using seccomp. Once seccomp is
1574 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1575 and the task is only allowed to execute a few safe syscalls
1576 defined by each seccomp mode.
1578 If unsure, say Y. Only embedded should say N here.
1580 source kernel/Kconfig.hz
1583 bool "kexec system call"
1585 kexec is a system call that implements the ability to shutdown your
1586 current kernel, and to start another kernel. It is like a reboot
1587 but it is independent of the system firmware. And like a reboot
1588 you can start any kernel with it, not just Linux.
1590 The name comes from the similarity to the exec system call.
1592 It is an ongoing process to be certain the hardware in a machine
1593 is properly shutdown, so do not be surprised if this code does not
1594 initially work for you. As of this writing the exact hardware
1595 interface is strongly in flux, so no good recommendation can be
1599 bool "kernel crash dumps"
1600 depends on X86_64 || (X86_32 && HIGHMEM)
1602 Generate crash dump after being started by kexec.
1603 This should be normally only set in special crash dump kernels
1604 which are loaded in the main kernel with kexec-tools into
1605 a specially reserved region and then later executed after
1606 a crash by kdump/kexec. The crash dump kernel must be compiled
1607 to a memory address not used by the main kernel or BIOS using
1608 PHYSICAL_START, or it must be built as a relocatable image
1609 (CONFIG_RELOCATABLE=y).
1610 For more details see Documentation/kdump/kdump.txt
1614 depends on KEXEC && HIBERNATION
1616 Jump between original kernel and kexeced kernel and invoke
1617 code in physical address mode via KEXEC
1619 config PHYSICAL_START
1620 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1623 This gives the physical address where the kernel is loaded.
1625 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1626 bzImage will decompress itself to above physical address and
1627 run from there. Otherwise, bzImage will run from the address where
1628 it has been loaded by the boot loader and will ignore above physical
1631 In normal kdump cases one does not have to set/change this option
1632 as now bzImage can be compiled as a completely relocatable image
1633 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1634 address. This option is mainly useful for the folks who don't want
1635 to use a bzImage for capturing the crash dump and want to use a
1636 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1637 to be specifically compiled to run from a specific memory area
1638 (normally a reserved region) and this option comes handy.
1640 So if you are using bzImage for capturing the crash dump,
1641 leave the value here unchanged to 0x1000000 and set
1642 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1643 for capturing the crash dump change this value to start of
1644 the reserved region. In other words, it can be set based on
1645 the "X" value as specified in the "crashkernel=YM@XM"
1646 command line boot parameter passed to the panic-ed
1647 kernel. Please take a look at Documentation/kdump/kdump.txt
1648 for more details about crash dumps.
1650 Usage of bzImage for capturing the crash dump is recommended as
1651 one does not have to build two kernels. Same kernel can be used
1652 as production kernel and capture kernel. Above option should have
1653 gone away after relocatable bzImage support is introduced. But it
1654 is present because there are users out there who continue to use
1655 vmlinux for dump capture. This option should go away down the
1658 Don't change this unless you know what you are doing.
1661 bool "Build a relocatable kernel"
1664 This builds a kernel image that retains relocation information
1665 so it can be loaded someplace besides the default 1MB.
1666 The relocations tend to make the kernel binary about 10% larger,
1667 but are discarded at runtime.
1669 One use is for the kexec on panic case where the recovery kernel
1670 must live at a different physical address than the primary
1673 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1674 it has been loaded at and the compile time physical address
1675 (CONFIG_PHYSICAL_START) is used as the minimum location.
1677 config RANDOMIZE_BASE
1678 bool "Randomize the address of the kernel image"
1679 depends on RELOCATABLE
1682 Randomizes the physical and virtual address at which the
1683 kernel image is decompressed, as a security feature that
1684 deters exploit attempts relying on knowledge of the location
1685 of kernel internals.
1687 Entropy is generated using the RDRAND instruction if it is
1688 supported. If RDTSC is supported, it is used as well. If
1689 neither RDRAND nor RDTSC are supported, then randomness is
1690 read from the i8254 timer.
1692 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1693 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1694 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1695 minimum of 2MiB, only 10 bits of entropy is theoretically
1696 possible. At best, due to page table layouts, 64-bit can use
1697 9 bits of entropy and 32-bit uses 8 bits.
1701 config RANDOMIZE_BASE_MAX_OFFSET
1702 hex "Maximum kASLR offset allowed" if EXPERT
1703 depends on RANDOMIZE_BASE
1704 range 0x0 0x20000000 if X86_32
1705 default "0x20000000" if X86_32
1706 range 0x0 0x40000000 if X86_64
1707 default "0x40000000" if X86_64
1709 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1710 memory is used to determine the maximal offset in bytes that will
1711 be applied to the kernel when kernel Address Space Layout
1712 Randomization (kASLR) is active. This must be a multiple of
1715 On 32-bit this is limited to 512MiB by page table layouts. The
1718 On 64-bit this is limited by how the kernel fixmap page table is
1719 positioned, so this cannot be larger than 1GiB currently. Without
1720 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1721 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1722 modules area will shrink to compensate, up to the current maximum
1723 1GiB to 1GiB split. The default is 1GiB.
1725 If unsure, leave at the default value.
1727 # Relocation on x86 needs some additional build support
1728 config X86_NEED_RELOCS
1730 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1732 config PHYSICAL_ALIGN
1733 hex "Alignment value to which kernel should be aligned"
1735 range 0x2000 0x1000000 if X86_32
1736 range 0x200000 0x1000000 if X86_64
1738 This value puts the alignment restrictions on physical address
1739 where kernel is loaded and run from. Kernel is compiled for an
1740 address which meets above alignment restriction.
1742 If bootloader loads the kernel at a non-aligned address and
1743 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1744 address aligned to above value and run from there.
1746 If bootloader loads the kernel at a non-aligned address and
1747 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1748 load address and decompress itself to the address it has been
1749 compiled for and run from there. The address for which kernel is
1750 compiled already meets above alignment restrictions. Hence the
1751 end result is that kernel runs from a physical address meeting
1752 above alignment restrictions.
1754 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1755 this value must be a multiple of 0x200000.
1757 Don't change this unless you know what you are doing.
1760 bool "Support for hot-pluggable CPUs"
1763 Say Y here to allow turning CPUs off and on. CPUs can be
1764 controlled through /sys/devices/system/cpu.
1765 ( Note: power management support will enable this option
1766 automatically on SMP systems. )
1767 Say N if you want to disable CPU hotplug.
1769 config BOOTPARAM_HOTPLUG_CPU0
1770 bool "Set default setting of cpu0_hotpluggable"
1772 depends on HOTPLUG_CPU
1774 Set whether default state of cpu0_hotpluggable is on or off.
1776 Say Y here to enable CPU0 hotplug by default. If this switch
1777 is turned on, there is no need to give cpu0_hotplug kernel
1778 parameter and the CPU0 hotplug feature is enabled by default.
1780 Please note: there are two known CPU0 dependencies if you want
1781 to enable the CPU0 hotplug feature either by this switch or by
1782 cpu0_hotplug kernel parameter.
1784 First, resume from hibernate or suspend always starts from CPU0.
1785 So hibernate and suspend are prevented if CPU0 is offline.
1787 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1788 offline if any interrupt can not migrate out of CPU0. There may
1789 be other CPU0 dependencies.
1791 Please make sure the dependencies are under your control before
1792 you enable this feature.
1794 Say N if you don't want to enable CPU0 hotplug feature by default.
1795 You still can enable the CPU0 hotplug feature at boot by kernel
1796 parameter cpu0_hotplug.
1798 config DEBUG_HOTPLUG_CPU0
1800 prompt "Debug CPU0 hotplug"
1801 depends on HOTPLUG_CPU
1803 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1804 soon as possible and boots up userspace with CPU0 offlined. User
1805 can online CPU0 back after boot time.
1807 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1808 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1809 compilation or giving cpu0_hotplug kernel parameter at boot.
1815 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1816 depends on X86_32 || IA32_EMULATION
1818 Certain buggy versions of glibc will crash if they are
1819 presented with a 32-bit vDSO that is not mapped at the address
1820 indicated in its segment table.
1822 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1823 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1824 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
1825 the only released version with the bug, but OpenSUSE 9
1826 contains a buggy "glibc 2.3.2".
1828 The symptom of the bug is that everything crashes on startup, saying:
1829 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1831 Saying Y here changes the default value of the vdso32 boot
1832 option from 1 to 0, which turns off the 32-bit vDSO entirely.
1833 This works around the glibc bug but hurts performance.
1835 If unsure, say N: if you are compiling your own kernel, you
1836 are unlikely to be using a buggy version of glibc.
1839 bool "Built-in kernel command line"
1841 Allow for specifying boot arguments to the kernel at
1842 build time. On some systems (e.g. embedded ones), it is
1843 necessary or convenient to provide some or all of the
1844 kernel boot arguments with the kernel itself (that is,
1845 to not rely on the boot loader to provide them.)
1847 To compile command line arguments into the kernel,
1848 set this option to 'Y', then fill in the
1849 the boot arguments in CONFIG_CMDLINE.
1851 Systems with fully functional boot loaders (i.e. non-embedded)
1852 should leave this option set to 'N'.
1855 string "Built-in kernel command string"
1856 depends on CMDLINE_BOOL
1859 Enter arguments here that should be compiled into the kernel
1860 image and used at boot time. If the boot loader provides a
1861 command line at boot time, it is appended to this string to
1862 form the full kernel command line, when the system boots.
1864 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1865 change this behavior.
1867 In most cases, the command line (whether built-in or provided
1868 by the boot loader) should specify the device for the root
1871 config CMDLINE_OVERRIDE
1872 bool "Built-in command line overrides boot loader arguments"
1873 depends on CMDLINE_BOOL
1875 Set this option to 'Y' to have the kernel ignore the boot loader
1876 command line, and use ONLY the built-in command line.
1878 This is used to work around broken boot loaders. This should
1879 be set to 'N' under normal conditions.
1883 config ARCH_ENABLE_MEMORY_HOTPLUG
1885 depends on X86_64 || (X86_32 && HIGHMEM)
1887 config ARCH_ENABLE_MEMORY_HOTREMOVE
1889 depends on MEMORY_HOTPLUG
1891 config USE_PERCPU_NUMA_NODE_ID
1895 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1897 depends on X86_64 || X86_PAE
1899 config ARCH_ENABLE_HUGEPAGE_MIGRATION
1901 depends on X86_64 && HUGETLB_PAGE && MIGRATION
1903 menu "Power management and ACPI options"
1905 config ARCH_HIBERNATION_HEADER
1907 depends on X86_64 && HIBERNATION
1909 source "kernel/power/Kconfig"
1911 source "drivers/acpi/Kconfig"
1913 source "drivers/sfi/Kconfig"
1920 tristate "APM (Advanced Power Management) BIOS support"
1921 depends on X86_32 && PM_SLEEP
1923 APM is a BIOS specification for saving power using several different
1924 techniques. This is mostly useful for battery powered laptops with
1925 APM compliant BIOSes. If you say Y here, the system time will be
1926 reset after a RESUME operation, the /proc/apm device will provide
1927 battery status information, and user-space programs will receive
1928 notification of APM "events" (e.g. battery status change).
1930 If you select "Y" here, you can disable actual use of the APM
1931 BIOS by passing the "apm=off" option to the kernel at boot time.
1933 Note that the APM support is almost completely disabled for
1934 machines with more than one CPU.
1936 In order to use APM, you will need supporting software. For location
1937 and more information, read <file:Documentation/power/apm-acpi.txt>
1938 and the Battery Powered Linux mini-HOWTO, available from
1939 <http://www.tldp.org/docs.html#howto>.
1941 This driver does not spin down disk drives (see the hdparm(8)
1942 manpage ("man 8 hdparm") for that), and it doesn't turn off
1943 VESA-compliant "green" monitors.
1945 This driver does not support the TI 4000M TravelMate and the ACER
1946 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1947 desktop machines also don't have compliant BIOSes, and this driver
1948 may cause those machines to panic during the boot phase.
1950 Generally, if you don't have a battery in your machine, there isn't
1951 much point in using this driver and you should say N. If you get
1952 random kernel OOPSes or reboots that don't seem to be related to
1953 anything, try disabling/enabling this option (or disabling/enabling
1956 Some other things you should try when experiencing seemingly random,
1959 1) make sure that you have enough swap space and that it is
1961 2) pass the "no-hlt" option to the kernel
1962 3) switch on floating point emulation in the kernel and pass
1963 the "no387" option to the kernel
1964 4) pass the "floppy=nodma" option to the kernel
1965 5) pass the "mem=4M" option to the kernel (thereby disabling
1966 all but the first 4 MB of RAM)
1967 6) make sure that the CPU is not over clocked.
1968 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1969 8) disable the cache from your BIOS settings
1970 9) install a fan for the video card or exchange video RAM
1971 10) install a better fan for the CPU
1972 11) exchange RAM chips
1973 12) exchange the motherboard.
1975 To compile this driver as a module, choose M here: the
1976 module will be called apm.
1980 config APM_IGNORE_USER_SUSPEND
1981 bool "Ignore USER SUSPEND"
1983 This option will ignore USER SUSPEND requests. On machines with a
1984 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1985 series notebooks, it is necessary to say Y because of a BIOS bug.
1987 config APM_DO_ENABLE
1988 bool "Enable PM at boot time"
1990 Enable APM features at boot time. From page 36 of the APM BIOS
1991 specification: "When disabled, the APM BIOS does not automatically
1992 power manage devices, enter the Standby State, enter the Suspend
1993 State, or take power saving steps in response to CPU Idle calls."
1994 This driver will make CPU Idle calls when Linux is idle (unless this
1995 feature is turned off -- see "Do CPU IDLE calls", below). This
1996 should always save battery power, but more complicated APM features
1997 will be dependent on your BIOS implementation. You may need to turn
1998 this option off if your computer hangs at boot time when using APM
1999 support, or if it beeps continuously instead of suspending. Turn
2000 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2001 T400CDT. This is off by default since most machines do fine without
2006 bool "Make CPU Idle calls when idle"
2008 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2009 On some machines, this can activate improved power savings, such as
2010 a slowed CPU clock rate, when the machine is idle. These idle calls
2011 are made after the idle loop has run for some length of time (e.g.,
2012 333 mS). On some machines, this will cause a hang at boot time or
2013 whenever the CPU becomes idle. (On machines with more than one CPU,
2014 this option does nothing.)
2016 config APM_DISPLAY_BLANK
2017 bool "Enable console blanking using APM"
2019 Enable console blanking using the APM. Some laptops can use this to
2020 turn off the LCD backlight when the screen blanker of the Linux
2021 virtual console blanks the screen. Note that this is only used by
2022 the virtual console screen blanker, and won't turn off the backlight
2023 when using the X Window system. This also doesn't have anything to
2024 do with your VESA-compliant power-saving monitor. Further, this
2025 option doesn't work for all laptops -- it might not turn off your
2026 backlight at all, or it might print a lot of errors to the console,
2027 especially if you are using gpm.
2029 config APM_ALLOW_INTS
2030 bool "Allow interrupts during APM BIOS calls"
2032 Normally we disable external interrupts while we are making calls to
2033 the APM BIOS as a measure to lessen the effects of a badly behaving
2034 BIOS implementation. The BIOS should reenable interrupts if it
2035 needs to. Unfortunately, some BIOSes do not -- especially those in
2036 many of the newer IBM Thinkpads. If you experience hangs when you
2037 suspend, try setting this to Y. Otherwise, say N.
2041 source "drivers/cpufreq/Kconfig"
2043 source "drivers/cpuidle/Kconfig"
2045 source "drivers/idle/Kconfig"
2050 menu "Bus options (PCI etc.)"
2056 Find out whether you have a PCI motherboard. PCI is the name of a
2057 bus system, i.e. the way the CPU talks to the other stuff inside
2058 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2059 VESA. If you have PCI, say Y, otherwise N.
2062 prompt "PCI access mode"
2063 depends on X86_32 && PCI
2066 On PCI systems, the BIOS can be used to detect the PCI devices and
2067 determine their configuration. However, some old PCI motherboards
2068 have BIOS bugs and may crash if this is done. Also, some embedded
2069 PCI-based systems don't have any BIOS at all. Linux can also try to
2070 detect the PCI hardware directly without using the BIOS.
2072 With this option, you can specify how Linux should detect the
2073 PCI devices. If you choose "BIOS", the BIOS will be used,
2074 if you choose "Direct", the BIOS won't be used, and if you
2075 choose "MMConfig", then PCI Express MMCONFIG will be used.
2076 If you choose "Any", the kernel will try MMCONFIG, then the
2077 direct access method and falls back to the BIOS if that doesn't
2078 work. If unsure, go with the default, which is "Any".
2083 config PCI_GOMMCONFIG
2100 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2102 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2105 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2109 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2113 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2117 depends on PCI && XEN
2125 bool "Support mmconfig PCI config space access"
2126 depends on X86_64 && PCI && ACPI
2128 config PCI_CNB20LE_QUIRK
2129 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2132 Read the PCI windows out of the CNB20LE host bridge. This allows
2133 PCI hotplug to work on systems with the CNB20LE chipset which do
2136 There's no public spec for this chipset, and this functionality
2137 is known to be incomplete.
2139 You should say N unless you know you need this.
2141 source "drivers/pci/pcie/Kconfig"
2143 source "drivers/pci/Kconfig"
2145 # x86_64 have no ISA slots, but can have ISA-style DMA.
2147 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2150 Enables ISA-style DMA support for devices requiring such controllers.
2158 Find out whether you have ISA slots on your motherboard. ISA is the
2159 name of a bus system, i.e. the way the CPU talks to the other stuff
2160 inside your box. Other bus systems are PCI, EISA, MicroChannel
2161 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2162 newer boards don't support it. If you have ISA, say Y, otherwise N.
2168 The Extended Industry Standard Architecture (EISA) bus was
2169 developed as an open alternative to the IBM MicroChannel bus.
2171 The EISA bus provided some of the features of the IBM MicroChannel
2172 bus while maintaining backward compatibility with cards made for
2173 the older ISA bus. The EISA bus saw limited use between 1988 and
2174 1995 when it was made obsolete by the PCI bus.
2176 Say Y here if you are building a kernel for an EISA-based machine.
2180 source "drivers/eisa/Kconfig"
2183 tristate "NatSemi SCx200 support"
2185 This provides basic support for National Semiconductor's
2186 (now AMD's) Geode processors. The driver probes for the
2187 PCI-IDs of several on-chip devices, so its a good dependency
2188 for other scx200_* drivers.
2190 If compiled as a module, the driver is named scx200.
2192 config SCx200HR_TIMER
2193 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2197 This driver provides a clocksource built upon the on-chip
2198 27MHz high-resolution timer. Its also a workaround for
2199 NSC Geode SC-1100's buggy TSC, which loses time when the
2200 processor goes idle (as is done by the scheduler). The
2201 other workaround is idle=poll boot option.
2204 bool "One Laptop Per Child support"
2211 Add support for detecting the unique features of the OLPC
2215 bool "OLPC XO-1 Power Management"
2216 depends on OLPC && MFD_CS5535 && PM_SLEEP
2219 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2222 bool "OLPC XO-1 Real Time Clock"
2223 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2225 Add support for the XO-1 real time clock, which can be used as a
2226 programmable wakeup source.
2229 bool "OLPC XO-1 SCI extras"
2230 depends on OLPC && OLPC_XO1_PM
2236 Add support for SCI-based features of the OLPC XO-1 laptop:
2237 - EC-driven system wakeups
2241 - AC adapter status updates
2242 - Battery status updates
2244 config OLPC_XO15_SCI
2245 bool "OLPC XO-1.5 SCI extras"
2246 depends on OLPC && ACPI
2249 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2250 - EC-driven system wakeups
2251 - AC adapter status updates
2252 - Battery status updates
2255 bool "PCEngines ALIX System Support (LED setup)"
2258 This option enables system support for the PCEngines ALIX.
2259 At present this just sets up LEDs for GPIO control on
2260 ALIX2/3/6 boards. However, other system specific setup should
2263 Note: You must still enable the drivers for GPIO and LED support
2264 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2266 Note: You have to set alix.force=1 for boards with Award BIOS.
2269 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2272 This option enables system support for the Soekris Engineering net5501.
2275 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2279 This option enables system support for the Traverse Technologies GEOS.
2282 bool "Technologic Systems TS-5500 platform support"
2284 select CHECK_SIGNATURE
2288 This option enables system support for the Technologic Systems TS-5500.
2294 depends on CPU_SUP_AMD && PCI
2296 source "drivers/pcmcia/Kconfig"
2298 source "drivers/pci/hotplug/Kconfig"
2301 tristate "RapidIO support"
2305 If enabled this option will include drivers and the core
2306 infrastructure code to support RapidIO interconnect devices.
2308 source "drivers/rapidio/Kconfig"
2311 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2313 Firmwares often provide initial graphics framebuffers so the BIOS,
2314 bootloader or kernel can show basic video-output during boot for
2315 user-guidance and debugging. Historically, x86 used the VESA BIOS
2316 Extensions and EFI-framebuffers for this, which are mostly limited
2318 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2319 framebuffers so the new generic system-framebuffer drivers can be
2320 used on x86. If the framebuffer is not compatible with the generic
2321 modes, it is adverticed as fallback platform framebuffer so legacy
2322 drivers like efifb, vesafb and uvesafb can pick it up.
2323 If this option is not selected, all system framebuffers are always
2324 marked as fallback platform framebuffers as usual.
2326 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2327 not be able to pick up generic system framebuffers if this option
2328 is selected. You are highly encouraged to enable simplefb as
2329 replacement if you select this option. simplefb can correctly deal
2330 with generic system framebuffers. But you should still keep vesafb
2331 and others enabled as fallback if a system framebuffer is
2332 incompatible with simplefb.
2339 menu "Executable file formats / Emulations"
2341 source "fs/Kconfig.binfmt"
2343 config IA32_EMULATION
2344 bool "IA32 Emulation"
2347 select COMPAT_BINFMT_ELF
2350 Include code to run legacy 32-bit programs under a
2351 64-bit kernel. You should likely turn this on, unless you're
2352 100% sure that you don't have any 32-bit programs left.
2355 tristate "IA32 a.out support"
2356 depends on IA32_EMULATION
2358 Support old a.out binaries in the 32bit emulation.
2361 bool "x32 ABI for 64-bit mode"
2362 depends on X86_64 && IA32_EMULATION
2364 Include code to run binaries for the x32 native 32-bit ABI
2365 for 64-bit processors. An x32 process gets access to the
2366 full 64-bit register file and wide data path while leaving
2367 pointers at 32 bits for smaller memory footprint.
2369 You will need a recent binutils (2.22 or later) with
2370 elf32_x86_64 support enabled to compile a kernel with this
2375 depends on IA32_EMULATION || X86_X32
2376 select ARCH_WANT_OLD_COMPAT_IPC
2379 config COMPAT_FOR_U64_ALIGNMENT
2382 config SYSVIPC_COMPAT
2394 config HAVE_ATOMIC_IOMAP
2398 config X86_DEV_DMA_OPS
2400 depends on X86_64 || STA2X11
2402 config X86_DMA_REMAP
2415 source "net/Kconfig"
2417 source "drivers/Kconfig"
2419 source "drivers/firmware/Kconfig"
2423 source "arch/x86/Kconfig.debug"
2425 source "security/Kconfig"
2427 source "crypto/Kconfig"
2429 source "arch/x86/kvm/Kconfig"
2431 source "lib/Kconfig"
projects / cascardo / linux.git / blob