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 if X86_64
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
45 select HAVE_KRETPROBES
46 select GENERIC_EARLY_IOREMAP
48 select HAVE_KPROBES_ON_FTRACE
49 select HAVE_FTRACE_MCOUNT_RECORD
50 select HAVE_FENTRY if X86_64
51 select HAVE_C_RECORDMCOUNT
52 select HAVE_DYNAMIC_FTRACE
53 select HAVE_DYNAMIC_FTRACE_WITH_REGS
54 select HAVE_FUNCTION_TRACER
55 select HAVE_FUNCTION_GRAPH_TRACER
56 select HAVE_FUNCTION_GRAPH_FP_TEST
57 select HAVE_FUNCTION_TRACE_MCOUNT_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 GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
113 select GENERIC_TIME_VSYSCALL
114 select KTIME_SCALAR if X86_32
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 OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
125 select OLD_SIGACTION if X86_32
126 select COMPAT_OLD_SIGACTION if IA32_EMULATION
128 select HAVE_DEBUG_STACKOVERFLOW
129 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
130 select HAVE_CC_STACKPROTECTOR
131 select GENERIC_CPU_AUTOPROBE
132 select HAVE_ARCH_AUDITSYSCALL
134 config INSTRUCTION_DECODER
136 depends on KPROBES || PERF_EVENTS || UPROBES
140 default "elf32-i386" if X86_32
141 default "elf64-x86-64" if X86_64
143 config ARCH_DEFCONFIG
145 default "arch/x86/configs/i386_defconfig" if X86_32
146 default "arch/x86/configs/x86_64_defconfig" if X86_64
148 config LOCKDEP_SUPPORT
151 config STACKTRACE_SUPPORT
154 config HAVE_LATENCYTOP_SUPPORT
163 config NEED_DMA_MAP_STATE
165 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
167 config NEED_SG_DMA_LENGTH
170 config GENERIC_ISA_DMA
172 depends on ISA_DMA_API
177 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
179 config GENERIC_BUG_RELATIVE_POINTERS
182 config GENERIC_HWEIGHT
185 config ARCH_MAY_HAVE_PC_FDC
187 depends on ISA_DMA_API
189 config RWSEM_XCHGADD_ALGORITHM
192 config GENERIC_CALIBRATE_DELAY
195 config ARCH_HAS_CPU_RELAX
198 config ARCH_HAS_CACHE_LINE_SIZE
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 config FIX_EARLYCON_MEM
267 source "init/Kconfig"
268 source "kernel/Kconfig.freezer"
270 menu "Processor type and features"
273 bool "DMA memory allocation support" if EXPERT
276 DMA memory allocation support allows devices with less than 32-bit
277 addressing to allocate within the first 16MB of address space.
278 Disable if no such devices will be used.
283 bool "Symmetric multi-processing support"
285 This enables support for systems with more than one CPU. If you have
286 a system with only one CPU, say N. If you have a system with more
289 If you say N here, the kernel will run on uni- and multiprocessor
290 machines, but will use only one CPU of a multiprocessor machine. If
291 you say Y here, the kernel will run on many, but not all,
292 uniprocessor machines. On a uniprocessor machine, the kernel
293 will run faster if you say N here.
295 Note that if you say Y here and choose architecture "586" or
296 "Pentium" under "Processor family", the kernel will not work on 486
297 architectures. Similarly, multiprocessor kernels for the "PPro"
298 architecture may not work on all Pentium based boards.
300 People using multiprocessor machines who say Y here should also say
301 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
302 Management" code will be disabled if you say Y here.
304 See also <file:Documentation/x86/i386/IO-APIC.txt>,
305 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
306 <http://www.tldp.org/docs.html#howto>.
308 If you don't know what to do here, say N.
311 bool "Support x2apic"
312 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
314 This enables x2apic support on CPUs that have this feature.
316 This allows 32-bit apic IDs (so it can support very large systems),
317 and accesses the local apic via MSRs not via mmio.
319 If you don't know what to do here, say N.
322 bool "Enable MPS table" if ACPI || SFI
324 depends on X86_LOCAL_APIC
326 For old smp systems that do not have proper acpi support. Newer systems
327 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
330 bool "Support for big SMP systems with more than 8 CPUs"
331 depends on X86_32 && SMP
333 This option is needed for the systems that have more than 8 CPUs
337 depends on X86_GOLDFISH
340 config X86_EXTENDED_PLATFORM
341 bool "Support for extended (non-PC) x86 platforms"
344 If you disable this option then the kernel will only support
345 standard PC platforms. (which covers the vast majority of
348 If you enable this option then you'll be able to select support
349 for the following (non-PC) 32 bit x86 platforms:
350 Goldfish (Android emulator)
353 SGI 320/540 (Visual Workstation)
354 STA2X11-based (e.g. Northville)
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)"
421 depends on X86_EXTENDED_PLATFORM
423 Enable support for the Goldfish virtual platform used primarily
424 for Android development. Unless you are building for the Android
425 Goldfish emulator say N here.
428 bool "CE4100 TV platform"
430 depends on PCI_GODIRECT
432 depends on X86_EXTENDED_PLATFORM
433 select X86_REBOOTFIXUPS
435 select OF_EARLY_FLATTREE
438 Select for the Intel CE media processor (CE4100) SOC.
439 This option compiles in support for the CE4100 SOC for settop
440 boxes and media devices.
443 bool "Intel MID platform support"
445 depends on X86_EXTENDED_PLATFORM
446 depends on X86_PLATFORM_DEVICES
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 bigsmp and STA2X11 default
492 subarchitectures. It is intended for a generic binary
493 kernel. If you select them all, kernel will probe it one by
494 one and will fallback to default.
496 # Alphabetically sorted list of Non standard 32 bit platforms
498 config X86_SUPPORTS_MEMORY_FAILURE
500 # MCE code calls memory_failure():
502 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
503 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
504 depends on X86_64 || !SPARSEMEM
505 select ARCH_SUPPORTS_MEMORY_FAILURE
508 bool "STA2X11 Companion Chip Support"
509 depends on X86_32_NON_STANDARD && PCI
510 select X86_DEV_DMA_OPS
514 select ARCH_REQUIRE_GPIOLIB
517 This adds support for boards based on the STA2X11 IO-Hub,
518 a.k.a. "ConneXt". The chip is used in place of the standard
519 PC chipset, so all "standard" peripherals are missing. If this
520 option is selected the kernel will still be able to boot on
521 standard PC machines.
524 tristate "Eurobraille/Iris poweroff module"
527 The Iris machines from EuroBraille do not have APM or ACPI support
528 to shut themselves down properly. A special I/O sequence is
529 needed to do so, which is what this module does at
532 This is only for Iris machines from EuroBraille.
536 config SCHED_OMIT_FRAME_POINTER
538 prompt "Single-depth WCHAN output"
541 Calculate simpler /proc/<PID>/wchan values. If this option
542 is disabled then wchan values will recurse back to the
543 caller function. This provides more accurate wchan values,
544 at the expense of slightly more scheduling overhead.
546 If in doubt, say "Y".
548 menuconfig HYPERVISOR_GUEST
549 bool "Linux guest support"
551 Say Y here to enable options for running Linux under various hyper-
552 visors. This option enables basic hypervisor detection and platform
555 If you say N, all options in this submenu will be skipped and
556 disabled, and Linux guest support won't be built in.
561 bool "Enable paravirtualization code"
563 This changes the kernel so it can modify itself when it is run
564 under a hypervisor, potentially improving performance significantly
565 over full virtualization. However, when run without a hypervisor
566 the kernel is theoretically slower and slightly larger.
568 config PARAVIRT_DEBUG
569 bool "paravirt-ops debugging"
570 depends on PARAVIRT && DEBUG_KERNEL
572 Enable to debug paravirt_ops internals. Specifically, BUG if
573 a paravirt_op is missing when it is called.
575 config PARAVIRT_SPINLOCKS
576 bool "Paravirtualization layer for spinlocks"
577 depends on PARAVIRT && SMP
578 select UNINLINE_SPIN_UNLOCK
580 Paravirtualized spinlocks allow a pvops backend to replace the
581 spinlock implementation with something virtualization-friendly
582 (for example, block the virtual CPU rather than spinning).
584 It has a minimal impact on native kernels and gives a nice performance
585 benefit on paravirtualized KVM / Xen kernels.
587 If you are unsure how to answer this question, answer Y.
589 source "arch/x86/xen/Kconfig"
592 bool "KVM Guest support (including kvmclock)"
594 select PARAVIRT_CLOCK
597 This option enables various optimizations for running under the KVM
598 hypervisor. It includes a paravirtualized clock, so that instead
599 of relying on a PIT (or probably other) emulation by the
600 underlying device model, the host provides the guest with
601 timing infrastructure such as time of day, and system time
604 bool "Enable debug information for KVM Guests in debugfs"
605 depends on KVM_GUEST && DEBUG_FS
608 This option enables collection of various statistics for KVM guest.
609 Statistics are displayed in debugfs filesystem. Enabling this option
610 may incur significant overhead.
612 source "arch/x86/lguest/Kconfig"
614 config PARAVIRT_TIME_ACCOUNTING
615 bool "Paravirtual steal time accounting"
619 Select this option to enable fine granularity task steal time
620 accounting. Time spent executing other tasks in parallel with
621 the current vCPU is discounted from the vCPU power. To account for
622 that, there can be a small performance impact.
624 If in doubt, say N here.
626 config PARAVIRT_CLOCK
629 endif #HYPERVISOR_GUEST
637 This option adds a kernel parameter 'memtest', which allows memtest
639 memtest=0, mean disabled; -- default
640 memtest=1, mean do 1 test pattern;
642 memtest=4, mean do 4 test patterns.
643 If you are unsure how to answer this question, answer N.
645 source "arch/x86/Kconfig.cpu"
649 prompt "HPET Timer Support" if X86_32
651 Use the IA-PC HPET (High Precision Event Timer) to manage
652 time in preference to the PIT and RTC, if a HPET is
654 HPET is the next generation timer replacing legacy 8254s.
655 The HPET provides a stable time base on SMP
656 systems, unlike the TSC, but it is more expensive to access,
657 as it is off-chip. You can find the HPET spec at
658 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
660 You can safely choose Y here. However, HPET will only be
661 activated if the platform and the BIOS support this feature.
662 Otherwise the 8254 will be used for timing services.
664 Choose N to continue using the legacy 8254 timer.
666 config HPET_EMULATE_RTC
668 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
671 def_bool y if X86_INTEL_MID
672 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
674 depends on X86_INTEL_MID && SFI
676 APB timer is the replacement for 8254, HPET on X86 MID platforms.
677 The APBT provides a stable time base on SMP
678 systems, unlike the TSC, but it is more expensive to access,
679 as it is off-chip. APB timers are always running regardless of CPU
680 C states, they are used as per CPU clockevent device when possible.
682 # Mark as expert because too many people got it wrong.
683 # The code disables itself when not needed.
686 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
687 bool "Enable DMI scanning" if EXPERT
689 Enabled scanning of DMI to identify machine quirks. Say Y
690 here unless you have verified that your setup is not
691 affected by entries in the DMI blacklist. Required by PNP
695 bool "Old AMD GART IOMMU support"
697 depends on X86_64 && PCI && AMD_NB
699 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
700 GART based hardware IOMMUs.
702 The GART supports full DMA access for devices with 32-bit access
703 limitations, on systems with more than 3 GB. This is usually needed
704 for USB, sound, many IDE/SATA chipsets and some other devices.
706 Newer systems typically have a modern AMD IOMMU, supported via
707 the CONFIG_AMD_IOMMU=y config option.
709 In normal configurations this driver is only active when needed:
710 there's more than 3 GB of memory and the system contains a
711 32-bit limited device.
716 bool "IBM Calgary IOMMU support"
718 depends on X86_64 && PCI
720 Support for hardware IOMMUs in IBM's xSeries x366 and x460
721 systems. Needed to run systems with more than 3GB of memory
722 properly with 32-bit PCI devices that do not support DAC
723 (Double Address Cycle). Calgary also supports bus level
724 isolation, where all DMAs pass through the IOMMU. This
725 prevents them from going anywhere except their intended
726 destination. This catches hard-to-find kernel bugs and
727 mis-behaving drivers and devices that do not use the DMA-API
728 properly to set up their DMA buffers. The IOMMU can be
729 turned off at boot time with the iommu=off parameter.
730 Normally the kernel will make the right choice by itself.
733 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
735 prompt "Should Calgary be enabled by default?"
736 depends on CALGARY_IOMMU
738 Should Calgary be enabled by default? if you choose 'y', Calgary
739 will be used (if it exists). If you choose 'n', Calgary will not be
740 used even if it exists. If you choose 'n' and would like to use
741 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
744 # need this always selected by IOMMU for the VIA workaround
748 Support for software bounce buffers used on x86-64 systems
749 which don't have a hardware IOMMU. Using this PCI devices
750 which can only access 32-bits of memory can be used on systems
751 with more than 3 GB of memory.
756 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
759 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
760 depends on X86_64 && SMP && DEBUG_KERNEL
761 select CPUMASK_OFFSTACK
763 Enable maximum number of CPUS and NUMA Nodes for this architecture.
767 int "Maximum number of CPUs" if SMP && !MAXSMP
768 range 2 8 if SMP && X86_32 && !X86_BIGSMP
769 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
770 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
772 default "8192" if MAXSMP
773 default "32" if SMP && X86_BIGSMP
776 This allows you to specify the maximum number of CPUs which this
777 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
778 supported value is 4096, otherwise the maximum value is 512. The
779 minimum value which makes sense is 2.
781 This is purely to save memory - each supported CPU adds
782 approximately eight kilobytes to the kernel image.
785 bool "SMT (Hyperthreading) scheduler support"
788 SMT scheduler support improves the CPU scheduler's decision making
789 when dealing with Intel Pentium 4 chips with HyperThreading at a
790 cost of slightly increased overhead in some places. If unsure say
795 prompt "Multi-core scheduler support"
798 Multi-core scheduler support improves the CPU scheduler's decision
799 making when dealing with multi-core CPU chips at a cost of slightly
800 increased overhead in some places. If unsure say N here.
802 source "kernel/Kconfig.preempt"
805 bool "Local APIC support on uniprocessors"
806 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
808 A local APIC (Advanced Programmable Interrupt Controller) is an
809 integrated interrupt controller in the CPU. If you have a single-CPU
810 system which has a processor with a local APIC, you can say Y here to
811 enable and use it. If you say Y here even though your machine doesn't
812 have a local APIC, then the kernel will still run with no slowdown at
813 all. The local APIC supports CPU-generated self-interrupts (timer,
814 performance counters), and the NMI watchdog which detects hard
818 bool "IO-APIC support on uniprocessors"
819 depends on X86_UP_APIC
821 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
822 SMP-capable replacement for PC-style interrupt controllers. Most
823 SMP systems and many recent uniprocessor systems have one.
825 If you have a single-CPU system with an IO-APIC, you can say Y here
826 to use it. If you say Y here even though your machine doesn't have
827 an IO-APIC, then the kernel will still run with no slowdown at all.
829 config X86_LOCAL_APIC
831 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
835 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
836 select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
838 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
839 bool "Reroute for broken boot IRQs"
840 depends on X86_IO_APIC
842 This option enables a workaround that fixes a source of
843 spurious interrupts. This is recommended when threaded
844 interrupt handling is used on systems where the generation of
845 superfluous "boot interrupts" cannot be disabled.
847 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
848 entry in the chipset's IO-APIC is masked (as, e.g. the RT
849 kernel does during interrupt handling). On chipsets where this
850 boot IRQ generation cannot be disabled, this workaround keeps
851 the original IRQ line masked so that only the equivalent "boot
852 IRQ" is delivered to the CPUs. The workaround also tells the
853 kernel to set up the IRQ handler on the boot IRQ line. In this
854 way only one interrupt is delivered to the kernel. Otherwise
855 the spurious second interrupt may cause the kernel to bring
856 down (vital) interrupt lines.
858 Only affects "broken" chipsets. Interrupt sharing may be
859 increased on these systems.
862 bool "Machine Check / overheating reporting"
865 Machine Check support allows the processor to notify the
866 kernel if it detects a problem (e.g. overheating, data corruption).
867 The action the kernel takes depends on the severity of the problem,
868 ranging from warning messages to halting the machine.
872 prompt "Intel MCE features"
873 depends on X86_MCE && X86_LOCAL_APIC
875 Additional support for intel specific MCE features such as
880 prompt "AMD MCE features"
881 depends on X86_MCE && X86_LOCAL_APIC
883 Additional support for AMD specific MCE features such as
884 the DRAM Error Threshold.
886 config X86_ANCIENT_MCE
887 bool "Support for old Pentium 5 / WinChip machine checks"
888 depends on X86_32 && X86_MCE
890 Include support for machine check handling on old Pentium 5 or WinChip
891 systems. These typically need to be enabled explicitly on the command
894 config X86_MCE_THRESHOLD
895 depends on X86_MCE_AMD || X86_MCE_INTEL
898 config X86_MCE_INJECT
900 tristate "Machine check injector support"
902 Provide support for injecting machine checks for testing purposes.
903 If you don't know what a machine check is and you don't do kernel
904 QA it is safe to say n.
906 config X86_THERMAL_VECTOR
908 depends on X86_MCE_INTEL
911 bool "Enable VM86 support" if EXPERT
915 This option is required by programs like DOSEMU to run 16-bit legacy
916 code on X86 processors. It also may be needed by software like
917 XFree86 to initialize some video cards via BIOS. Disabling this
918 option saves about 6k.
921 tristate "Toshiba Laptop support"
924 This adds a driver to safely access the System Management Mode of
925 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
926 not work on models with a Phoenix BIOS. The System Management Mode
927 is used to set the BIOS and power saving options on Toshiba portables.
929 For information on utilities to make use of this driver see the
930 Toshiba Linux utilities web site at:
931 <http://www.buzzard.org.uk/toshiba/>.
933 Say Y if you intend to run this kernel on a Toshiba portable.
937 tristate "Dell laptop support"
940 This adds a driver to safely access the System Management Mode
941 of the CPU on the Dell Inspiron 8000. The System Management Mode
942 is used to read cpu temperature and cooling fan status and to
943 control the fans on the I8K portables.
945 This driver has been tested only on the Inspiron 8000 but it may
946 also work with other Dell laptops. You can force loading on other
947 models by passing the parameter `force=1' to the module. Use at
950 For information on utilities to make use of this driver see the
951 I8K Linux utilities web site at:
952 <http://people.debian.org/~dz/i8k/>
954 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
957 config X86_REBOOTFIXUPS
958 bool "Enable X86 board specific fixups for reboot"
961 This enables chipset and/or board specific fixups to be done
962 in order to get reboot to work correctly. This is only needed on
963 some combinations of hardware and BIOS. The symptom, for which
964 this config is intended, is when reboot ends with a stalled/hung
967 Currently, the only fixup is for the Geode machines using
968 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
970 Say Y if you want to enable the fixup. Currently, it's safe to
971 enable this option even if you don't need it.
975 tristate "CPU microcode loading support"
976 depends on CPU_SUP_AMD || CPU_SUP_INTEL
980 If you say Y here, you will be able to update the microcode on
981 certain Intel and AMD processors. The Intel support is for the
982 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
983 Xeon etc. The AMD support is for families 0x10 and later. You will
984 obviously need the actual microcode binary data itself which is not
985 shipped with the Linux kernel.
987 This option selects the general module only, you need to select
988 at least one vendor specific module as well.
990 To compile this driver as a module, choose M here: the module
991 will be called microcode.
993 config MICROCODE_INTEL
994 bool "Intel microcode loading support"
999 This options enables microcode patch loading support for Intel
1002 For the current Intel microcode data package go to
1003 <https://downloadcenter.intel.com> and search for
1004 'Linux Processor Microcode Data File'.
1006 config MICROCODE_AMD
1007 bool "AMD microcode loading support"
1008 depends on MICROCODE
1011 If you select this option, microcode patch loading support for AMD
1012 processors will be enabled.
1014 config MICROCODE_OLD_INTERFACE
1016 depends on MICROCODE
1018 config MICROCODE_INTEL_EARLY
1021 config MICROCODE_AMD_EARLY
1024 config MICROCODE_EARLY
1025 bool "Early load microcode"
1026 depends on MICROCODE=y && BLK_DEV_INITRD
1027 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1028 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1031 This option provides functionality to read additional microcode data
1032 at the beginning of initrd image. The data tells kernel to load
1033 microcode to CPU's as early as possible. No functional change if no
1034 microcode data is glued to the initrd, therefore it's safe to say Y.
1037 tristate "/dev/cpu/*/msr - Model-specific register support"
1039 This device gives privileged processes access to the x86
1040 Model-Specific Registers (MSRs). It is a character device with
1041 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1042 MSR accesses are directed to a specific CPU on multi-processor
1046 tristate "/dev/cpu/*/cpuid - CPU information support"
1048 This device gives processes access to the x86 CPUID instruction to
1049 be executed on a specific processor. It is a character device
1050 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1054 prompt "High Memory Support"
1061 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1062 However, the address space of 32-bit x86 processors is only 4
1063 Gigabytes large. That means that, if you have a large amount of
1064 physical memory, not all of it can be "permanently mapped" by the
1065 kernel. The physical memory that's not permanently mapped is called
1068 If you are compiling a kernel which will never run on a machine with
1069 more than 1 Gigabyte total physical RAM, answer "off" here (default
1070 choice and suitable for most users). This will result in a "3GB/1GB"
1071 split: 3GB are mapped so that each process sees a 3GB virtual memory
1072 space and the remaining part of the 4GB virtual memory space is used
1073 by the kernel to permanently map as much physical memory as
1076 If the machine has between 1 and 4 Gigabytes physical RAM, then
1079 If more than 4 Gigabytes is used then answer "64GB" here. This
1080 selection turns Intel PAE (Physical Address Extension) mode on.
1081 PAE implements 3-level paging on IA32 processors. PAE is fully
1082 supported by Linux, PAE mode is implemented on all recent Intel
1083 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1084 then the kernel will not boot on CPUs that don't support PAE!
1086 The actual amount of total physical memory will either be
1087 auto detected or can be forced by using a kernel command line option
1088 such as "mem=256M". (Try "man bootparam" or see the documentation of
1089 your boot loader (lilo or loadlin) about how to pass options to the
1090 kernel at boot time.)
1092 If unsure, say "off".
1097 Select this if you have a 32-bit processor and between 1 and 4
1098 gigabytes of physical RAM.
1105 Select this if you have a 32-bit processor and more than 4
1106 gigabytes of physical RAM.
1111 prompt "Memory split" if EXPERT
1115 Select the desired split between kernel and user memory.
1117 If the address range available to the kernel is less than the
1118 physical memory installed, the remaining memory will be available
1119 as "high memory". Accessing high memory is a little more costly
1120 than low memory, as it needs to be mapped into the kernel first.
1121 Note that increasing the kernel address space limits the range
1122 available to user programs, making the address space there
1123 tighter. Selecting anything other than the default 3G/1G split
1124 will also likely make your kernel incompatible with binary-only
1127 If you are not absolutely sure what you are doing, leave this
1131 bool "3G/1G user/kernel split"
1132 config VMSPLIT_3G_OPT
1134 bool "3G/1G user/kernel split (for full 1G low memory)"
1136 bool "2G/2G user/kernel split"
1137 config VMSPLIT_2G_OPT
1139 bool "2G/2G user/kernel split (for full 2G low memory)"
1141 bool "1G/3G user/kernel split"
1146 default 0xB0000000 if VMSPLIT_3G_OPT
1147 default 0x80000000 if VMSPLIT_2G
1148 default 0x78000000 if VMSPLIT_2G_OPT
1149 default 0x40000000 if VMSPLIT_1G
1155 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1158 bool "PAE (Physical Address Extension) Support"
1159 depends on X86_32 && !HIGHMEM4G
1161 PAE is required for NX support, and furthermore enables
1162 larger swapspace support for non-overcommit purposes. It
1163 has the cost of more pagetable lookup overhead, and also
1164 consumes more pagetable space per process.
1166 config ARCH_PHYS_ADDR_T_64BIT
1168 depends on X86_64 || X86_PAE
1170 config ARCH_DMA_ADDR_T_64BIT
1172 depends on X86_64 || HIGHMEM64G
1174 config DIRECT_GBPAGES
1175 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1179 Allow the kernel linear mapping to use 1GB pages on CPUs that
1180 support it. This can improve the kernel's performance a tiny bit by
1181 reducing TLB pressure. If in doubt, say "Y".
1183 # Common NUMA Features
1185 bool "Numa Memory Allocation and Scheduler Support"
1187 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1188 default y if X86_BIGSMP
1190 Enable NUMA (Non Uniform Memory Access) support.
1192 The kernel will try to allocate memory used by a CPU on the
1193 local memory controller of the CPU and add some more
1194 NUMA awareness to the kernel.
1196 For 64-bit this is recommended if the system is Intel Core i7
1197 (or later), AMD Opteron, or EM64T NUMA.
1199 For 32-bit this is only needed if you boot a 32-bit
1200 kernel on a 64-bit NUMA platform.
1202 Otherwise, you should say N.
1206 prompt "Old style AMD Opteron NUMA detection"
1207 depends on X86_64 && NUMA && PCI
1209 Enable AMD NUMA node topology detection. You should say Y here if
1210 you have a multi processor AMD system. This uses an old method to
1211 read the NUMA configuration directly from the builtin Northbridge
1212 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1213 which also takes priority if both are compiled in.
1215 config X86_64_ACPI_NUMA
1217 prompt "ACPI NUMA detection"
1218 depends on X86_64 && NUMA && ACPI && PCI
1221 Enable ACPI SRAT based node topology detection.
1223 # Some NUMA nodes have memory ranges that span
1224 # other nodes. Even though a pfn is valid and
1225 # between a node's start and end pfns, it may not
1226 # reside on that node. See memmap_init_zone()
1228 config NODES_SPAN_OTHER_NODES
1230 depends on X86_64_ACPI_NUMA
1233 bool "NUMA emulation"
1236 Enable NUMA emulation. A flat machine will be split
1237 into virtual nodes when booted with "numa=fake=N", where N is the
1238 number of nodes. This is only useful for debugging.
1241 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1243 default "10" if MAXSMP
1244 default "6" if X86_64
1246 depends on NEED_MULTIPLE_NODES
1248 Specify the maximum number of NUMA Nodes available on the target
1249 system. Increases memory reserved to accommodate various tables.
1251 config ARCH_HAVE_MEMORY_PRESENT
1253 depends on X86_32 && DISCONTIGMEM
1255 config NEED_NODE_MEMMAP_SIZE
1257 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1259 config ARCH_FLATMEM_ENABLE
1261 depends on X86_32 && !NUMA
1263 config ARCH_DISCONTIGMEM_ENABLE
1265 depends on NUMA && X86_32
1267 config ARCH_DISCONTIGMEM_DEFAULT
1269 depends on NUMA && X86_32
1271 config ARCH_SPARSEMEM_ENABLE
1273 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1274 select SPARSEMEM_STATIC if X86_32
1275 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1277 config ARCH_SPARSEMEM_DEFAULT
1281 config ARCH_SELECT_MEMORY_MODEL
1283 depends on ARCH_SPARSEMEM_ENABLE
1285 config ARCH_MEMORY_PROBE
1286 bool "Enable sysfs memory/probe interface"
1287 depends on X86_64 && MEMORY_HOTPLUG
1289 This option enables a sysfs memory/probe interface for testing.
1290 See Documentation/memory-hotplug.txt for more information.
1291 If you are unsure how to answer this question, answer N.
1293 config ARCH_PROC_KCORE_TEXT
1295 depends on X86_64 && PROC_KCORE
1297 config ILLEGAL_POINTER_VALUE
1300 default 0xdead000000000000 if X86_64
1305 bool "Allocate 3rd-level pagetables from highmem"
1308 The VM uses one page table entry for each page of physical memory.
1309 For systems with a lot of RAM, this can be wasteful of precious
1310 low memory. Setting this option will put user-space page table
1311 entries in high memory.
1313 config X86_CHECK_BIOS_CORRUPTION
1314 bool "Check for low memory corruption"
1316 Periodically check for memory corruption in low memory, which
1317 is suspected to be caused by BIOS. Even when enabled in the
1318 configuration, it is disabled at runtime. Enable it by
1319 setting "memory_corruption_check=1" on the kernel command
1320 line. By default it scans the low 64k of memory every 60
1321 seconds; see the memory_corruption_check_size and
1322 memory_corruption_check_period parameters in
1323 Documentation/kernel-parameters.txt to adjust this.
1325 When enabled with the default parameters, this option has
1326 almost no overhead, as it reserves a relatively small amount
1327 of memory and scans it infrequently. It both detects corruption
1328 and prevents it from affecting the running system.
1330 It is, however, intended as a diagnostic tool; if repeatable
1331 BIOS-originated corruption always affects the same memory,
1332 you can use memmap= to prevent the kernel from using that
1335 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1336 bool "Set the default setting of memory_corruption_check"
1337 depends on X86_CHECK_BIOS_CORRUPTION
1340 Set whether the default state of memory_corruption_check is
1343 config X86_RESERVE_LOW
1344 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1348 Specify the amount of low memory to reserve for the BIOS.
1350 The first page contains BIOS data structures that the kernel
1351 must not use, so that page must always be reserved.
1353 By default we reserve the first 64K of physical RAM, as a
1354 number of BIOSes are known to corrupt that memory range
1355 during events such as suspend/resume or monitor cable
1356 insertion, so it must not be used by the kernel.
1358 You can set this to 4 if you are absolutely sure that you
1359 trust the BIOS to get all its memory reservations and usages
1360 right. If you know your BIOS have problems beyond the
1361 default 64K area, you can set this to 640 to avoid using the
1362 entire low memory range.
1364 If you have doubts about the BIOS (e.g. suspend/resume does
1365 not work or there's kernel crashes after certain hardware
1366 hotplug events) then you might want to enable
1367 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1368 typical corruption patterns.
1370 Leave this to the default value of 64 if you are unsure.
1372 config MATH_EMULATION
1374 prompt "Math emulation" if X86_32
1376 Linux can emulate a math coprocessor (used for floating point
1377 operations) if you don't have one. 486DX and Pentium processors have
1378 a math coprocessor built in, 486SX and 386 do not, unless you added
1379 a 487DX or 387, respectively. (The messages during boot time can
1380 give you some hints here ["man dmesg"].) Everyone needs either a
1381 coprocessor or this emulation.
1383 If you don't have a math coprocessor, you need to say Y here; if you
1384 say Y here even though you have a coprocessor, the coprocessor will
1385 be used nevertheless. (This behavior can be changed with the kernel
1386 command line option "no387", which comes handy if your coprocessor
1387 is broken. Try "man bootparam" or see the documentation of your boot
1388 loader (lilo or loadlin) about how to pass options to the kernel at
1389 boot time.) This means that it is a good idea to say Y here if you
1390 intend to use this kernel on different machines.
1392 More information about the internals of the Linux math coprocessor
1393 emulation can be found in <file:arch/x86/math-emu/README>.
1395 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1396 kernel, it won't hurt.
1400 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1402 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1403 the Memory Type Range Registers (MTRRs) may be used to control
1404 processor access to memory ranges. This is most useful if you have
1405 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1406 allows bus write transfers to be combined into a larger transfer
1407 before bursting over the PCI/AGP bus. This can increase performance
1408 of image write operations 2.5 times or more. Saying Y here creates a
1409 /proc/mtrr file which may be used to manipulate your processor's
1410 MTRRs. Typically the X server should use this.
1412 This code has a reasonably generic interface so that similar
1413 control registers on other processors can be easily supported
1416 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1417 Registers (ARRs) which provide a similar functionality to MTRRs. For
1418 these, the ARRs are used to emulate the MTRRs.
1419 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1420 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1421 write-combining. All of these processors are supported by this code
1422 and it makes sense to say Y here if you have one of them.
1424 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1425 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1426 can lead to all sorts of problems, so it's good to say Y here.
1428 You can safely say Y even if your machine doesn't have MTRRs, you'll
1429 just add about 9 KB to your kernel.
1431 See <file:Documentation/x86/mtrr.txt> for more information.
1433 config MTRR_SANITIZER
1435 prompt "MTRR cleanup support"
1438 Convert MTRR layout from continuous to discrete, so X drivers can
1439 add writeback entries.
1441 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1442 The largest mtrr entry size for a continuous block can be set with
1447 config MTRR_SANITIZER_ENABLE_DEFAULT
1448 int "MTRR cleanup enable value (0-1)"
1451 depends on MTRR_SANITIZER
1453 Enable mtrr cleanup default value
1455 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1456 int "MTRR cleanup spare reg num (0-7)"
1459 depends on MTRR_SANITIZER
1461 mtrr cleanup spare entries default, it can be changed via
1462 mtrr_spare_reg_nr=N on the kernel command line.
1466 prompt "x86 PAT support" if EXPERT
1469 Use PAT attributes to setup page level cache control.
1471 PATs are the modern equivalents of MTRRs and are much more
1472 flexible than MTRRs.
1474 Say N here if you see bootup problems (boot crash, boot hang,
1475 spontaneous reboots) or a non-working video driver.
1479 config ARCH_USES_PG_UNCACHED
1485 prompt "x86 architectural random number generator" if EXPERT
1487 Enable the x86 architectural RDRAND instruction
1488 (Intel Bull Mountain technology) to generate random numbers.
1489 If supported, this is a high bandwidth, cryptographically
1490 secure hardware random number generator.
1494 prompt "Supervisor Mode Access Prevention" if EXPERT
1496 Supervisor Mode Access Prevention (SMAP) is a security
1497 feature in newer Intel processors. There is a small
1498 performance cost if this enabled and turned on; there is
1499 also a small increase in the kernel size if this is enabled.
1504 bool "EFI runtime service support"
1508 This enables the kernel to use EFI runtime services that are
1509 available (such as the EFI variable services).
1511 This option is only useful on systems that have EFI firmware.
1512 In addition, you should use the latest ELILO loader available
1513 at <http://elilo.sourceforge.net> in order to take advantage
1514 of EFI runtime services. However, even with this option, the
1515 resultant kernel should continue to boot on existing non-EFI
1519 bool "EFI stub support"
1522 This kernel feature allows a bzImage to be loaded directly
1523 by EFI firmware without the use of a bootloader.
1525 See Documentation/efi-stub.txt for more information.
1528 bool "EFI mixed-mode support"
1529 depends on EFI_STUB && X86_64
1531 Enabling this feature allows a 64-bit kernel to be booted
1532 on a 32-bit firmware, provided that your CPU supports 64-bit
1535 Note that it is not possible to boot a mixed-mode enabled
1536 kernel via the EFI boot stub - a bootloader that supports
1537 the EFI handover protocol must be used.
1543 prompt "Enable seccomp to safely compute untrusted bytecode"
1545 This kernel feature is useful for number crunching applications
1546 that may need to compute untrusted bytecode during their
1547 execution. By using pipes or other transports made available to
1548 the process as file descriptors supporting the read/write
1549 syscalls, it's possible to isolate those applications in
1550 their own address space using seccomp. Once seccomp is
1551 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1552 and the task is only allowed to execute a few safe syscalls
1553 defined by each seccomp mode.
1555 If unsure, say Y. Only embedded should say N here.
1557 source kernel/Kconfig.hz
1560 bool "kexec system call"
1562 kexec is a system call that implements the ability to shutdown your
1563 current kernel, and to start another kernel. It is like a reboot
1564 but it is independent of the system firmware. And like a reboot
1565 you can start any kernel with it, not just Linux.
1567 The name comes from the similarity to the exec system call.
1569 It is an ongoing process to be certain the hardware in a machine
1570 is properly shutdown, so do not be surprised if this code does not
1571 initially work for you. As of this writing the exact hardware
1572 interface is strongly in flux, so no good recommendation can be
1576 bool "kernel crash dumps"
1577 depends on X86_64 || (X86_32 && HIGHMEM)
1579 Generate crash dump after being started by kexec.
1580 This should be normally only set in special crash dump kernels
1581 which are loaded in the main kernel with kexec-tools into
1582 a specially reserved region and then later executed after
1583 a crash by kdump/kexec. The crash dump kernel must be compiled
1584 to a memory address not used by the main kernel or BIOS using
1585 PHYSICAL_START, or it must be built as a relocatable image
1586 (CONFIG_RELOCATABLE=y).
1587 For more details see Documentation/kdump/kdump.txt
1591 depends on KEXEC && HIBERNATION
1593 Jump between original kernel and kexeced kernel and invoke
1594 code in physical address mode via KEXEC
1596 config PHYSICAL_START
1597 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1600 This gives the physical address where the kernel is loaded.
1602 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1603 bzImage will decompress itself to above physical address and
1604 run from there. Otherwise, bzImage will run from the address where
1605 it has been loaded by the boot loader and will ignore above physical
1608 In normal kdump cases one does not have to set/change this option
1609 as now bzImage can be compiled as a completely relocatable image
1610 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1611 address. This option is mainly useful for the folks who don't want
1612 to use a bzImage for capturing the crash dump and want to use a
1613 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1614 to be specifically compiled to run from a specific memory area
1615 (normally a reserved region) and this option comes handy.
1617 So if you are using bzImage for capturing the crash dump,
1618 leave the value here unchanged to 0x1000000 and set
1619 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1620 for capturing the crash dump change this value to start of
1621 the reserved region. In other words, it can be set based on
1622 the "X" value as specified in the "crashkernel=YM@XM"
1623 command line boot parameter passed to the panic-ed
1624 kernel. Please take a look at Documentation/kdump/kdump.txt
1625 for more details about crash dumps.
1627 Usage of bzImage for capturing the crash dump is recommended as
1628 one does not have to build two kernels. Same kernel can be used
1629 as production kernel and capture kernel. Above option should have
1630 gone away after relocatable bzImage support is introduced. But it
1631 is present because there are users out there who continue to use
1632 vmlinux for dump capture. This option should go away down the
1635 Don't change this unless you know what you are doing.
1638 bool "Build a relocatable kernel"
1641 This builds a kernel image that retains relocation information
1642 so it can be loaded someplace besides the default 1MB.
1643 The relocations tend to make the kernel binary about 10% larger,
1644 but are discarded at runtime.
1646 One use is for the kexec on panic case where the recovery kernel
1647 must live at a different physical address than the primary
1650 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1651 it has been loaded at and the compile time physical address
1652 (CONFIG_PHYSICAL_START) is used as the minimum location.
1654 config RANDOMIZE_BASE
1655 bool "Randomize the address of the kernel image"
1656 depends on RELOCATABLE
1657 depends on !HIBERNATION
1660 Randomizes the physical and virtual address at which the
1661 kernel image is decompressed, as a security feature that
1662 deters exploit attempts relying on knowledge of the location
1663 of kernel internals.
1665 Entropy is generated using the RDRAND instruction if it is
1666 supported. If RDTSC is supported, it is used as well. If
1667 neither RDRAND nor RDTSC are supported, then randomness is
1668 read from the i8254 timer.
1670 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1671 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1672 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1673 minimum of 2MiB, only 10 bits of entropy is theoretically
1674 possible. At best, due to page table layouts, 64-bit can use
1675 9 bits of entropy and 32-bit uses 8 bits.
1679 config RANDOMIZE_BASE_MAX_OFFSET
1680 hex "Maximum kASLR offset allowed" if EXPERT
1681 depends on RANDOMIZE_BASE
1682 range 0x0 0x20000000 if X86_32
1683 default "0x20000000" if X86_32
1684 range 0x0 0x40000000 if X86_64
1685 default "0x40000000" if X86_64
1687 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1688 memory is used to determine the maximal offset in bytes that will
1689 be applied to the kernel when kernel Address Space Layout
1690 Randomization (kASLR) is active. This must be a multiple of
1693 On 32-bit this is limited to 512MiB by page table layouts. The
1696 On 64-bit this is limited by how the kernel fixmap page table is
1697 positioned, so this cannot be larger than 1GiB currently. Without
1698 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1699 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1700 modules area will shrink to compensate, up to the current maximum
1701 1GiB to 1GiB split. The default is 1GiB.
1703 If unsure, leave at the default value.
1705 # Relocation on x86 needs some additional build support
1706 config X86_NEED_RELOCS
1708 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1710 config PHYSICAL_ALIGN
1711 hex "Alignment value to which kernel should be aligned"
1713 range 0x2000 0x1000000 if X86_32
1714 range 0x200000 0x1000000 if X86_64
1716 This value puts the alignment restrictions on physical address
1717 where kernel is loaded and run from. Kernel is compiled for an
1718 address which meets above alignment restriction.
1720 If bootloader loads the kernel at a non-aligned address and
1721 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1722 address aligned to above value and run from there.
1724 If bootloader loads the kernel at a non-aligned address and
1725 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1726 load address and decompress itself to the address it has been
1727 compiled for and run from there. The address for which kernel is
1728 compiled already meets above alignment restrictions. Hence the
1729 end result is that kernel runs from a physical address meeting
1730 above alignment restrictions.
1732 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1733 this value must be a multiple of 0x200000.
1735 Don't change this unless you know what you are doing.
1738 bool "Support for hot-pluggable CPUs"
1741 Say Y here to allow turning CPUs off and on. CPUs can be
1742 controlled through /sys/devices/system/cpu.
1743 ( Note: power management support will enable this option
1744 automatically on SMP systems. )
1745 Say N if you want to disable CPU hotplug.
1747 config BOOTPARAM_HOTPLUG_CPU0
1748 bool "Set default setting of cpu0_hotpluggable"
1750 depends on HOTPLUG_CPU
1752 Set whether default state of cpu0_hotpluggable is on or off.
1754 Say Y here to enable CPU0 hotplug by default. If this switch
1755 is turned on, there is no need to give cpu0_hotplug kernel
1756 parameter and the CPU0 hotplug feature is enabled by default.
1758 Please note: there are two known CPU0 dependencies if you want
1759 to enable the CPU0 hotplug feature either by this switch or by
1760 cpu0_hotplug kernel parameter.
1762 First, resume from hibernate or suspend always starts from CPU0.
1763 So hibernate and suspend are prevented if CPU0 is offline.
1765 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1766 offline if any interrupt can not migrate out of CPU0. There may
1767 be other CPU0 dependencies.
1769 Please make sure the dependencies are under your control before
1770 you enable this feature.
1772 Say N if you don't want to enable CPU0 hotplug feature by default.
1773 You still can enable the CPU0 hotplug feature at boot by kernel
1774 parameter cpu0_hotplug.
1776 config DEBUG_HOTPLUG_CPU0
1778 prompt "Debug CPU0 hotplug"
1779 depends on HOTPLUG_CPU
1781 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1782 soon as possible and boots up userspace with CPU0 offlined. User
1783 can online CPU0 back after boot time.
1785 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1786 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1787 compilation or giving cpu0_hotplug kernel parameter at boot.
1793 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1794 depends on X86_32 || IA32_EMULATION
1796 Certain buggy versions of glibc will crash if they are
1797 presented with a 32-bit vDSO that is not mapped at the address
1798 indicated in its segment table.
1800 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1801 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1802 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
1803 the only released version with the bug, but OpenSUSE 9
1804 contains a buggy "glibc 2.3.2".
1806 The symptom of the bug is that everything crashes on startup, saying:
1807 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1809 Saying Y here changes the default value of the vdso32 boot
1810 option from 1 to 0, which turns off the 32-bit vDSO entirely.
1811 This works around the glibc bug but hurts performance.
1813 If unsure, say N: if you are compiling your own kernel, you
1814 are unlikely to be using a buggy version of glibc.
1817 bool "Built-in kernel command line"
1819 Allow for specifying boot arguments to the kernel at
1820 build time. On some systems (e.g. embedded ones), it is
1821 necessary or convenient to provide some or all of the
1822 kernel boot arguments with the kernel itself (that is,
1823 to not rely on the boot loader to provide them.)
1825 To compile command line arguments into the kernel,
1826 set this option to 'Y', then fill in the
1827 the boot arguments in CONFIG_CMDLINE.
1829 Systems with fully functional boot loaders (i.e. non-embedded)
1830 should leave this option set to 'N'.
1833 string "Built-in kernel command string"
1834 depends on CMDLINE_BOOL
1837 Enter arguments here that should be compiled into the kernel
1838 image and used at boot time. If the boot loader provides a
1839 command line at boot time, it is appended to this string to
1840 form the full kernel command line, when the system boots.
1842 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1843 change this behavior.
1845 In most cases, the command line (whether built-in or provided
1846 by the boot loader) should specify the device for the root
1849 config CMDLINE_OVERRIDE
1850 bool "Built-in command line overrides boot loader arguments"
1851 depends on CMDLINE_BOOL
1853 Set this option to 'Y' to have the kernel ignore the boot loader
1854 command line, and use ONLY the built-in command line.
1856 This is used to work around broken boot loaders. This should
1857 be set to 'N' under normal conditions.
1861 config ARCH_ENABLE_MEMORY_HOTPLUG
1863 depends on X86_64 || (X86_32 && HIGHMEM)
1865 config ARCH_ENABLE_MEMORY_HOTREMOVE
1867 depends on MEMORY_HOTPLUG
1869 config USE_PERCPU_NUMA_NODE_ID
1873 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1875 depends on X86_64 || X86_PAE
1877 config ARCH_ENABLE_HUGEPAGE_MIGRATION
1879 depends on X86_64 && HUGETLB_PAGE && MIGRATION
1881 menu "Power management and ACPI options"
1883 config ARCH_HIBERNATION_HEADER
1885 depends on X86_64 && HIBERNATION
1887 source "kernel/power/Kconfig"
1889 source "drivers/acpi/Kconfig"
1891 source "drivers/sfi/Kconfig"
1898 tristate "APM (Advanced Power Management) BIOS support"
1899 depends on X86_32 && PM_SLEEP
1901 APM is a BIOS specification for saving power using several different
1902 techniques. This is mostly useful for battery powered laptops with
1903 APM compliant BIOSes. If you say Y here, the system time will be
1904 reset after a RESUME operation, the /proc/apm device will provide
1905 battery status information, and user-space programs will receive
1906 notification of APM "events" (e.g. battery status change).
1908 If you select "Y" here, you can disable actual use of the APM
1909 BIOS by passing the "apm=off" option to the kernel at boot time.
1911 Note that the APM support is almost completely disabled for
1912 machines with more than one CPU.
1914 In order to use APM, you will need supporting software. For location
1915 and more information, read <file:Documentation/power/apm-acpi.txt>
1916 and the Battery Powered Linux mini-HOWTO, available from
1917 <http://www.tldp.org/docs.html#howto>.
1919 This driver does not spin down disk drives (see the hdparm(8)
1920 manpage ("man 8 hdparm") for that), and it doesn't turn off
1921 VESA-compliant "green" monitors.
1923 This driver does not support the TI 4000M TravelMate and the ACER
1924 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1925 desktop machines also don't have compliant BIOSes, and this driver
1926 may cause those machines to panic during the boot phase.
1928 Generally, if you don't have a battery in your machine, there isn't
1929 much point in using this driver and you should say N. If you get
1930 random kernel OOPSes or reboots that don't seem to be related to
1931 anything, try disabling/enabling this option (or disabling/enabling
1934 Some other things you should try when experiencing seemingly random,
1937 1) make sure that you have enough swap space and that it is
1939 2) pass the "no-hlt" option to the kernel
1940 3) switch on floating point emulation in the kernel and pass
1941 the "no387" option to the kernel
1942 4) pass the "floppy=nodma" option to the kernel
1943 5) pass the "mem=4M" option to the kernel (thereby disabling
1944 all but the first 4 MB of RAM)
1945 6) make sure that the CPU is not over clocked.
1946 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1947 8) disable the cache from your BIOS settings
1948 9) install a fan for the video card or exchange video RAM
1949 10) install a better fan for the CPU
1950 11) exchange RAM chips
1951 12) exchange the motherboard.
1953 To compile this driver as a module, choose M here: the
1954 module will be called apm.
1958 config APM_IGNORE_USER_SUSPEND
1959 bool "Ignore USER SUSPEND"
1961 This option will ignore USER SUSPEND requests. On machines with a
1962 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1963 series notebooks, it is necessary to say Y because of a BIOS bug.
1965 config APM_DO_ENABLE
1966 bool "Enable PM at boot time"
1968 Enable APM features at boot time. From page 36 of the APM BIOS
1969 specification: "When disabled, the APM BIOS does not automatically
1970 power manage devices, enter the Standby State, enter the Suspend
1971 State, or take power saving steps in response to CPU Idle calls."
1972 This driver will make CPU Idle calls when Linux is idle (unless this
1973 feature is turned off -- see "Do CPU IDLE calls", below). This
1974 should always save battery power, but more complicated APM features
1975 will be dependent on your BIOS implementation. You may need to turn
1976 this option off if your computer hangs at boot time when using APM
1977 support, or if it beeps continuously instead of suspending. Turn
1978 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1979 T400CDT. This is off by default since most machines do fine without
1984 bool "Make CPU Idle calls when idle"
1986 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1987 On some machines, this can activate improved power savings, such as
1988 a slowed CPU clock rate, when the machine is idle. These idle calls
1989 are made after the idle loop has run for some length of time (e.g.,
1990 333 mS). On some machines, this will cause a hang at boot time or
1991 whenever the CPU becomes idle. (On machines with more than one CPU,
1992 this option does nothing.)
1994 config APM_DISPLAY_BLANK
1995 bool "Enable console blanking using APM"
1997 Enable console blanking using the APM. Some laptops can use this to
1998 turn off the LCD backlight when the screen blanker of the Linux
1999 virtual console blanks the screen. Note that this is only used by
2000 the virtual console screen blanker, and won't turn off the backlight
2001 when using the X Window system. This also doesn't have anything to
2002 do with your VESA-compliant power-saving monitor. Further, this
2003 option doesn't work for all laptops -- it might not turn off your
2004 backlight at all, or it might print a lot of errors to the console,
2005 especially if you are using gpm.
2007 config APM_ALLOW_INTS
2008 bool "Allow interrupts during APM BIOS calls"
2010 Normally we disable external interrupts while we are making calls to
2011 the APM BIOS as a measure to lessen the effects of a badly behaving
2012 BIOS implementation. The BIOS should reenable interrupts if it
2013 needs to. Unfortunately, some BIOSes do not -- especially those in
2014 many of the newer IBM Thinkpads. If you experience hangs when you
2015 suspend, try setting this to Y. Otherwise, say N.
2019 source "drivers/cpufreq/Kconfig"
2021 source "drivers/cpuidle/Kconfig"
2023 source "drivers/idle/Kconfig"
2028 menu "Bus options (PCI etc.)"
2034 Find out whether you have a PCI motherboard. PCI is the name of a
2035 bus system, i.e. the way the CPU talks to the other stuff inside
2036 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2037 VESA. If you have PCI, say Y, otherwise N.
2040 prompt "PCI access mode"
2041 depends on X86_32 && PCI
2044 On PCI systems, the BIOS can be used to detect the PCI devices and
2045 determine their configuration. However, some old PCI motherboards
2046 have BIOS bugs and may crash if this is done. Also, some embedded
2047 PCI-based systems don't have any BIOS at all. Linux can also try to
2048 detect the PCI hardware directly without using the BIOS.
2050 With this option, you can specify how Linux should detect the
2051 PCI devices. If you choose "BIOS", the BIOS will be used,
2052 if you choose "Direct", the BIOS won't be used, and if you
2053 choose "MMConfig", then PCI Express MMCONFIG will be used.
2054 If you choose "Any", the kernel will try MMCONFIG, then the
2055 direct access method and falls back to the BIOS if that doesn't
2056 work. If unsure, go with the default, which is "Any".
2061 config PCI_GOMMCONFIG
2078 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2080 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2083 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2087 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2091 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2095 depends on PCI && XEN
2103 bool "Support mmconfig PCI config space access"
2104 depends on X86_64 && PCI && ACPI
2106 config PCI_CNB20LE_QUIRK
2107 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2110 Read the PCI windows out of the CNB20LE host bridge. This allows
2111 PCI hotplug to work on systems with the CNB20LE chipset which do
2114 There's no public spec for this chipset, and this functionality
2115 is known to be incomplete.
2117 You should say N unless you know you need this.
2119 source "drivers/pci/pcie/Kconfig"
2121 source "drivers/pci/Kconfig"
2123 # x86_64 have no ISA slots, but can have ISA-style DMA.
2125 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2128 Enables ISA-style DMA support for devices requiring such controllers.
2136 Find out whether you have ISA slots on your motherboard. ISA is the
2137 name of a bus system, i.e. the way the CPU talks to the other stuff
2138 inside your box. Other bus systems are PCI, EISA, MicroChannel
2139 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2140 newer boards don't support it. If you have ISA, say Y, otherwise N.
2146 The Extended Industry Standard Architecture (EISA) bus was
2147 developed as an open alternative to the IBM MicroChannel bus.
2149 The EISA bus provided some of the features of the IBM MicroChannel
2150 bus while maintaining backward compatibility with cards made for
2151 the older ISA bus. The EISA bus saw limited use between 1988 and
2152 1995 when it was made obsolete by the PCI bus.
2154 Say Y here if you are building a kernel for an EISA-based machine.
2158 source "drivers/eisa/Kconfig"
2161 tristate "NatSemi SCx200 support"
2163 This provides basic support for National Semiconductor's
2164 (now AMD's) Geode processors. The driver probes for the
2165 PCI-IDs of several on-chip devices, so its a good dependency
2166 for other scx200_* drivers.
2168 If compiled as a module, the driver is named scx200.
2170 config SCx200HR_TIMER
2171 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2175 This driver provides a clocksource built upon the on-chip
2176 27MHz high-resolution timer. Its also a workaround for
2177 NSC Geode SC-1100's buggy TSC, which loses time when the
2178 processor goes idle (as is done by the scheduler). The
2179 other workaround is idle=poll boot option.
2182 bool "One Laptop Per Child support"
2189 Add support for detecting the unique features of the OLPC
2193 bool "OLPC XO-1 Power Management"
2194 depends on OLPC && MFD_CS5535 && PM_SLEEP
2197 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2200 bool "OLPC XO-1 Real Time Clock"
2201 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2203 Add support for the XO-1 real time clock, which can be used as a
2204 programmable wakeup source.
2207 bool "OLPC XO-1 SCI extras"
2208 depends on OLPC && OLPC_XO1_PM
2214 Add support for SCI-based features of the OLPC XO-1 laptop:
2215 - EC-driven system wakeups
2219 - AC adapter status updates
2220 - Battery status updates
2222 config OLPC_XO15_SCI
2223 bool "OLPC XO-1.5 SCI extras"
2224 depends on OLPC && ACPI
2227 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2228 - EC-driven system wakeups
2229 - AC adapter status updates
2230 - Battery status updates
2233 bool "PCEngines ALIX System Support (LED setup)"
2236 This option enables system support for the PCEngines ALIX.
2237 At present this just sets up LEDs for GPIO control on
2238 ALIX2/3/6 boards. However, other system specific setup should
2241 Note: You must still enable the drivers for GPIO and LED support
2242 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2244 Note: You have to set alix.force=1 for boards with Award BIOS.
2247 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2250 This option enables system support for the Soekris Engineering net5501.
2253 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2257 This option enables system support for the Traverse Technologies GEOS.
2260 bool "Technologic Systems TS-5500 platform support"
2262 select CHECK_SIGNATURE
2266 This option enables system support for the Technologic Systems TS-5500.
2272 depends on CPU_SUP_AMD && PCI
2274 source "drivers/pcmcia/Kconfig"
2276 source "drivers/pci/hotplug/Kconfig"
2279 tristate "RapidIO support"
2283 If enabled this option will include drivers and the core
2284 infrastructure code to support RapidIO interconnect devices.
2286 source "drivers/rapidio/Kconfig"
2289 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2291 Firmwares often provide initial graphics framebuffers so the BIOS,
2292 bootloader or kernel can show basic video-output during boot for
2293 user-guidance and debugging. Historically, x86 used the VESA BIOS
2294 Extensions and EFI-framebuffers for this, which are mostly limited
2296 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2297 framebuffers so the new generic system-framebuffer drivers can be
2298 used on x86. If the framebuffer is not compatible with the generic
2299 modes, it is adverticed as fallback platform framebuffer so legacy
2300 drivers like efifb, vesafb and uvesafb can pick it up.
2301 If this option is not selected, all system framebuffers are always
2302 marked as fallback platform framebuffers as usual.
2304 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2305 not be able to pick up generic system framebuffers if this option
2306 is selected. You are highly encouraged to enable simplefb as
2307 replacement if you select this option. simplefb can correctly deal
2308 with generic system framebuffers. But you should still keep vesafb
2309 and others enabled as fallback if a system framebuffer is
2310 incompatible with simplefb.
2317 menu "Executable file formats / Emulations"
2319 source "fs/Kconfig.binfmt"
2321 config IA32_EMULATION
2322 bool "IA32 Emulation"
2325 select COMPAT_BINFMT_ELF
2328 Include code to run legacy 32-bit programs under a
2329 64-bit kernel. You should likely turn this on, unless you're
2330 100% sure that you don't have any 32-bit programs left.
2333 tristate "IA32 a.out support"
2334 depends on IA32_EMULATION
2336 Support old a.out binaries in the 32bit emulation.
2339 bool "x32 ABI for 64-bit mode"
2340 depends on X86_64 && IA32_EMULATION
2342 Include code to run binaries for the x32 native 32-bit ABI
2343 for 64-bit processors. An x32 process gets access to the
2344 full 64-bit register file and wide data path while leaving
2345 pointers at 32 bits for smaller memory footprint.
2347 You will need a recent binutils (2.22 or later) with
2348 elf32_x86_64 support enabled to compile a kernel with this
2353 depends on IA32_EMULATION || X86_X32
2354 select ARCH_WANT_OLD_COMPAT_IPC
2357 config COMPAT_FOR_U64_ALIGNMENT
2360 config SYSVIPC_COMPAT
2372 config HAVE_ATOMIC_IOMAP
2376 config X86_DEV_DMA_OPS
2378 depends on X86_64 || STA2X11
2380 config X86_DMA_REMAP
2389 source "net/Kconfig"
2391 source "drivers/Kconfig"
2393 source "drivers/firmware/Kconfig"
2397 source "arch/x86/Kconfig.debug"
2399 source "security/Kconfig"
2401 source "crypto/Kconfig"
2403 source "arch/x86/kvm/Kconfig"
2405 source "lib/Kconfig"
projects / linux-drm-fsl-dcu.git / blob