3 bool "64-bit kernel" if ARCH = "x86"
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
18 select X86_DEV_DMA_OPS
19 select ARCH_USE_CMPXCHG_LOCKREF
24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
25 select HAVE_AOUT if X86_32
26 select HAVE_UNSTABLE_SCHED_CLOCK
27 select ARCH_SUPPORTS_NUMA_BALANCING
28 select ARCH_WANTS_PROT_NUMA_PROT_NONE
31 select HAVE_PCSPKR_PLATFORM
32 select HAVE_PERF_EVENTS
33 select HAVE_IOREMAP_PROT
36 select HAVE_MEMBLOCK_NODE_MAP
37 select ARCH_DISCARD_MEMBLOCK
38 select ARCH_WANT_OPTIONAL_GPIOLIB
39 select ARCH_WANT_FRAME_POINTERS
41 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
42 select HAVE_KRETPROBES
44 select HAVE_KPROBES_ON_FTRACE
45 select HAVE_FTRACE_MCOUNT_RECORD
46 select HAVE_FENTRY if X86_64
47 select HAVE_C_RECORDMCOUNT
48 select HAVE_DYNAMIC_FTRACE
49 select HAVE_DYNAMIC_FTRACE_WITH_REGS
50 select HAVE_FUNCTION_TRACER
51 select HAVE_FUNCTION_GRAPH_TRACER
52 select HAVE_FUNCTION_GRAPH_FP_TEST
53 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
54 select HAVE_SYSCALL_TRACEPOINTS
55 select SYSCTL_EXCEPTION_TRACE
58 select HAVE_ARCH_TRACEHOOK
59 select HAVE_GENERIC_DMA_COHERENT if X86_32
60 select HAVE_EFFICIENT_UNALIGNED_ACCESS
61 select USER_STACKTRACE_SUPPORT
62 select HAVE_REGS_AND_STACK_ACCESS_API
63 select HAVE_DMA_API_DEBUG
64 select HAVE_KERNEL_GZIP
65 select HAVE_KERNEL_BZIP2
66 select HAVE_KERNEL_LZMA
68 select HAVE_KERNEL_LZO
69 select HAVE_KERNEL_LZ4
70 select HAVE_HW_BREAKPOINT
71 select HAVE_MIXED_BREAKPOINTS_REGS
73 select HAVE_PERF_EVENTS_NMI
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_DEBUG_KMEMLEAK
78 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
79 select HAVE_CMPXCHG_LOCAL
80 select HAVE_CMPXCHG_DOUBLE
81 select HAVE_ARCH_KMEMCHECK
82 select HAVE_USER_RETURN_NOTIFIER
83 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
84 select HAVE_ARCH_JUMP_LABEL
85 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
87 select GENERIC_FIND_FIRST_BIT
88 select GENERIC_IRQ_PROBE
89 select GENERIC_PENDING_IRQ if SMP
90 select GENERIC_IRQ_SHOW
91 select GENERIC_CLOCKEVENTS_MIN_ADJUST
92 select IRQ_FORCED_THREADING
93 select USE_GENERIC_SMP_HELPERS if SMP
94 select HAVE_BPF_JIT if X86_64
95 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
97 select ARCH_HAVE_NMI_SAFE_CMPXCHG
99 select DCACHE_WORD_ACCESS
100 select GENERIC_SMP_IDLE_THREAD
101 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
102 select HAVE_ARCH_SECCOMP_FILTER
103 select BUILDTIME_EXTABLE_SORT
104 select GENERIC_CMOS_UPDATE
105 select HAVE_ARCH_SOFT_DIRTY
106 select CLOCKSOURCE_WATCHDOG
107 select GENERIC_CLOCKEVENTS
108 select ARCH_CLOCKSOURCE_DATA if X86_64
109 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
110 select GENERIC_TIME_VSYSCALL if X86_64
111 select KTIME_SCALAR if X86_32
112 select GENERIC_STRNCPY_FROM_USER
113 select GENERIC_STRNLEN_USER
114 select HAVE_CONTEXT_TRACKING if X86_64
115 select HAVE_IRQ_TIME_ACCOUNTING
117 select MODULES_USE_ELF_REL if X86_32
118 select MODULES_USE_ELF_RELA if X86_64
119 select CLONE_BACKWARDS if X86_32
120 select ARCH_USE_BUILTIN_BSWAP
121 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
122 select OLD_SIGACTION if X86_32
123 select COMPAT_OLD_SIGACTION if IA32_EMULATION
125 select HAVE_DEBUG_STACKOVERFLOW
126 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
128 config INSTRUCTION_DECODER
130 depends on KPROBES || PERF_EVENTS || UPROBES
134 default "elf32-i386" if X86_32
135 default "elf64-x86-64" if X86_64
137 config ARCH_DEFCONFIG
139 default "arch/x86/configs/i386_defconfig" if X86_32
140 default "arch/x86/configs/x86_64_defconfig" if X86_64
142 config LOCKDEP_SUPPORT
145 config STACKTRACE_SUPPORT
148 config HAVE_LATENCYTOP_SUPPORT
157 config NEED_DMA_MAP_STATE
159 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
161 config NEED_SG_DMA_LENGTH
164 config GENERIC_ISA_DMA
166 depends on ISA_DMA_API
171 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
173 config GENERIC_BUG_RELATIVE_POINTERS
176 config GENERIC_HWEIGHT
179 config ARCH_MAY_HAVE_PC_FDC
181 depends on ISA_DMA_API
183 config RWSEM_XCHGADD_ALGORITHM
186 config GENERIC_CALIBRATE_DELAY
189 config ARCH_HAS_CPU_RELAX
192 config ARCH_HAS_CACHE_LINE_SIZE
195 config ARCH_HAS_CPU_AUTOPROBE
198 config HAVE_SETUP_PER_CPU_AREA
201 config NEED_PER_CPU_EMBED_FIRST_CHUNK
204 config NEED_PER_CPU_PAGE_FIRST_CHUNK
207 config ARCH_HIBERNATION_POSSIBLE
210 config ARCH_SUSPEND_POSSIBLE
213 config ARCH_WANT_HUGE_PMD_SHARE
216 config ARCH_WANT_GENERAL_HUGETLB
227 config ARCH_SUPPORTS_OPTIMIZED_INLINING
230 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
233 config HAVE_INTEL_TXT
235 depends on INTEL_IOMMU && ACPI
239 depends on X86_32 && SMP
243 depends on X86_64 && SMP
249 config X86_32_LAZY_GS
251 depends on X86_32 && !CC_STACKPROTECTOR
253 config ARCH_HWEIGHT_CFLAGS
255 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
256 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
258 config ARCH_CPU_PROBE_RELEASE
260 depends on HOTPLUG_CPU
262 config ARCH_SUPPORTS_UPROBES
265 source "init/Kconfig"
266 source "kernel/Kconfig.freezer"
268 menu "Processor type and features"
271 bool "DMA memory allocation support" if EXPERT
274 DMA memory allocation support allows devices with less than 32-bit
275 addressing to allocate within the first 16MB of address space.
276 Disable if no such devices will be used.
281 bool "Symmetric multi-processing support"
283 This enables support for systems with more than one CPU. If you have
284 a system with only one CPU, like most personal computers, say N. If
285 you have a system with more than one CPU, say Y.
287 If you say N here, the kernel will run on single and multiprocessor
288 machines, but will use only one CPU of a multiprocessor machine. If
289 you say Y here, the kernel will run on many, but not all,
290 singleprocessor machines. On a singleprocessor machine, the kernel
291 will run faster if you say N here.
293 Note that if you say Y here and choose architecture "586" or
294 "Pentium" under "Processor family", the kernel will not work on 486
295 architectures. Similarly, multiprocessor kernels for the "PPro"
296 architecture may not work on all Pentium based boards.
298 People using multiprocessor machines who say Y here should also say
299 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
300 Management" code will be disabled if you say Y here.
302 See also <file:Documentation/x86/i386/IO-APIC.txt>,
303 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
304 <http://www.tldp.org/docs.html#howto>.
306 If you don't know what to do here, say N.
309 bool "Support x2apic"
310 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
312 This enables x2apic support on CPUs that have this feature.
314 This allows 32-bit apic IDs (so it can support very large systems),
315 and accesses the local apic via MSRs not via mmio.
317 If you don't know what to do here, say N.
320 bool "Enable MPS table" if ACPI || SFI
322 depends on X86_LOCAL_APIC
324 For old smp systems that do not have proper acpi support. Newer systems
325 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
328 bool "Support for big SMP systems with more than 8 CPUs"
329 depends on X86_32 && SMP
331 This option is needed for the systems that have more than 8 CPUs
335 depends on X86_GOLDFISH
338 config X86_EXTENDED_PLATFORM
339 bool "Support for extended (non-PC) x86 platforms"
342 If you disable this option then the kernel will only support
343 standard PC platforms. (which covers the vast majority of
346 If you enable this option then you'll be able to select support
347 for the following (non-PC) 32 bit x86 platforms:
348 Goldfish (Android emulator)
352 SGI 320/540 (Visual Workstation)
353 STA2X11-based (e.g. Northville)
354 Summit/EXA (IBM x440)
355 Unisys ES7000 IA32 series
356 Moorestown MID devices
358 If you have one of these systems, or if you want to build a
359 generic distribution kernel, say Y here - otherwise say N.
363 config X86_EXTENDED_PLATFORM
364 bool "Support for extended (non-PC) x86 platforms"
367 If you disable this option then the kernel will only support
368 standard PC platforms. (which covers the vast majority of
371 If you enable this option then you'll be able to select support
372 for the following (non-PC) 64 bit x86 platforms:
377 If you have one of these systems, or if you want to build a
378 generic distribution kernel, say Y here - otherwise say N.
380 # This is an alphabetically sorted list of 64 bit extended platforms
381 # Please maintain the alphabetic order if and when there are additions
383 bool "Numascale NumaChip"
385 depends on X86_EXTENDED_PLATFORM
388 depends on X86_X2APIC
389 depends on PCI_MMCONFIG
391 Adds support for Numascale NumaChip large-SMP systems. Needed to
392 enable more than ~168 cores.
393 If you don't have one of these, you should say N here.
397 select HYPERVISOR_GUEST
399 depends on X86_64 && PCI
400 depends on X86_EXTENDED_PLATFORM
403 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
404 supposed to run on these EM64T-based machines. Only choose this option
405 if you have one of these machines.
408 bool "SGI Ultraviolet"
410 depends on X86_EXTENDED_PLATFORM
412 depends on X86_X2APIC
414 This option is needed in order to support SGI Ultraviolet systems.
415 If you don't have one of these, you should say N here.
417 # Following is an alphabetically sorted list of 32 bit extended platforms
418 # Please maintain the alphabetic order if and when there are additions
421 bool "Goldfish (Virtual Platform)"
423 depends on X86_EXTENDED_PLATFORM
425 Enable support for the Goldfish virtual platform used primarily
426 for Android development. Unless you are building for the Android
427 Goldfish emulator say N here.
430 bool "CE4100 TV platform"
432 depends on PCI_GODIRECT
434 depends on X86_EXTENDED_PLATFORM
435 select X86_REBOOTFIXUPS
437 select OF_EARLY_FLATTREE
440 Select for the Intel CE media processor (CE4100) SOC.
441 This option compiles in support for the CE4100 SOC for settop
442 boxes and media devices.
444 config X86_WANT_INTEL_MID
445 bool "Intel MID platform support"
447 depends on X86_EXTENDED_PLATFORM
449 Select to build a kernel capable of supporting Intel MID platform
450 systems which do not have the PCI legacy interfaces (Moorestown,
451 Medfield). If you are building for a PC class system say N here.
453 if X86_WANT_INTEL_MID
459 bool "Medfield MID platform"
462 depends on X86_IO_APIC
470 select X86_PLATFORM_DEVICES
471 select MFD_INTEL_MSIC
473 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
474 Internet Device(MID) platform.
475 Unlike standard x86 PCs, Medfield does not have many legacy devices
476 nor standard legacy replacement devices/features. e.g. Medfield does
477 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
481 config X86_INTEL_LPSS
482 bool "Intel Low Power Subsystem Support"
487 Select to build support for Intel Low Power Subsystem such as
488 found on Intel Lynxpoint PCH. Selecting this option enables
489 things like clock tree (common clock framework) and pincontrol
490 which are needed by the LPSS peripheral drivers.
493 bool "RDC R-321x SoC"
495 depends on X86_EXTENDED_PLATFORM
497 select X86_REBOOTFIXUPS
499 This option is needed for RDC R-321x system-on-chip, also known
501 If you don't have one of these chips, you should say N here.
503 config X86_32_NON_STANDARD
504 bool "Support non-standard 32-bit SMP architectures"
505 depends on X86_32 && SMP
506 depends on X86_EXTENDED_PLATFORM
508 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
509 STA2X11, default subarchitectures. It is intended for a generic
510 binary kernel. If you select them all, kernel will probe it
511 one by one and will fallback to default.
513 # Alphabetically sorted list of Non standard 32 bit platforms
516 bool "NUMAQ (IBM/Sequent)"
517 depends on X86_32_NON_STANDARD
522 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
523 NUMA multiquad box. This changes the way that processors are
524 bootstrapped, and uses Clustered Logical APIC addressing mode instead
525 of Flat Logical. You will need a new lynxer.elf file to flash your
526 firmware with - send email to <Martin.Bligh@us.ibm.com>.
528 config X86_SUPPORTS_MEMORY_FAILURE
530 # MCE code calls memory_failure():
532 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
533 depends on !X86_NUMAQ
534 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
535 depends on X86_64 || !SPARSEMEM
536 select ARCH_SUPPORTS_MEMORY_FAILURE
539 bool "SGI 320/540 (Visual Workstation)"
540 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
541 depends on X86_32_NON_STANDARD
543 The SGI Visual Workstation series is an IA32-based workstation
544 based on SGI systems chips with some legacy PC hardware attached.
546 Say Y here to create a kernel to run on the SGI 320 or 540.
548 A kernel compiled for the Visual Workstation will run on general
549 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
552 bool "STA2X11 Companion Chip Support"
553 depends on X86_32_NON_STANDARD && PCI
554 select X86_DEV_DMA_OPS
558 select ARCH_REQUIRE_GPIOLIB
561 This adds support for boards based on the STA2X11 IO-Hub,
562 a.k.a. "ConneXt". The chip is used in place of the standard
563 PC chipset, so all "standard" peripherals are missing. If this
564 option is selected the kernel will still be able to boot on
565 standard PC machines.
568 bool "Summit/EXA (IBM x440)"
569 depends on X86_32_NON_STANDARD
571 This option is needed for IBM systems that use the Summit/EXA chipset.
572 In particular, it is needed for the x440.
575 bool "Unisys ES7000 IA32 series"
576 depends on X86_32_NON_STANDARD && X86_BIGSMP
578 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
579 supposed to run on an IA32-based Unisys ES7000 system.
582 tristate "Eurobraille/Iris poweroff module"
585 The Iris machines from EuroBraille do not have APM or ACPI support
586 to shut themselves down properly. A special I/O sequence is
587 needed to do so, which is what this module does at
590 This is only for Iris machines from EuroBraille.
594 config SCHED_OMIT_FRAME_POINTER
596 prompt "Single-depth WCHAN output"
599 Calculate simpler /proc/<PID>/wchan values. If this option
600 is disabled then wchan values will recurse back to the
601 caller function. This provides more accurate wchan values,
602 at the expense of slightly more scheduling overhead.
604 If in doubt, say "Y".
606 menuconfig HYPERVISOR_GUEST
607 bool "Linux guest support"
609 Say Y here to enable options for running Linux under various hyper-
610 visors. This option enables basic hypervisor detection and platform
613 If you say N, all options in this submenu will be skipped and
614 disabled, and Linux guest support won't be built in.
619 bool "Enable paravirtualization code"
621 This changes the kernel so it can modify itself when it is run
622 under a hypervisor, potentially improving performance significantly
623 over full virtualization. However, when run without a hypervisor
624 the kernel is theoretically slower and slightly larger.
626 config PARAVIRT_DEBUG
627 bool "paravirt-ops debugging"
628 depends on PARAVIRT && DEBUG_KERNEL
630 Enable to debug paravirt_ops internals. Specifically, BUG if
631 a paravirt_op is missing when it is called.
633 config PARAVIRT_SPINLOCKS
634 bool "Paravirtualization layer for spinlocks"
635 depends on PARAVIRT && SMP
636 select UNINLINE_SPIN_UNLOCK
638 Paravirtualized spinlocks allow a pvops backend to replace the
639 spinlock implementation with something virtualization-friendly
640 (for example, block the virtual CPU rather than spinning).
642 Unfortunately the downside is an up to 5% performance hit on
643 native kernels, with various workloads.
645 If you are unsure how to answer this question, answer N.
647 source "arch/x86/xen/Kconfig"
650 bool "KVM Guest support (including kvmclock)"
652 select PARAVIRT_CLOCK
655 This option enables various optimizations for running under the KVM
656 hypervisor. It includes a paravirtualized clock, so that instead
657 of relying on a PIT (or probably other) emulation by the
658 underlying device model, the host provides the guest with
659 timing infrastructure such as time of day, and system time
662 bool "Enable debug information for KVM Guests in debugfs"
663 depends on KVM_GUEST && DEBUG_FS
666 This option enables collection of various statistics for KVM guest.
667 Statistics are displayed in debugfs filesystem. Enabling this option
668 may incur significant overhead.
670 source "arch/x86/lguest/Kconfig"
672 config PARAVIRT_TIME_ACCOUNTING
673 bool "Paravirtual steal time accounting"
677 Select this option to enable fine granularity task steal time
678 accounting. Time spent executing other tasks in parallel with
679 the current vCPU is discounted from the vCPU power. To account for
680 that, there can be a small performance impact.
682 If in doubt, say N here.
684 config PARAVIRT_CLOCK
687 endif #HYPERVISOR_GUEST
695 This option adds a kernel parameter 'memtest', which allows memtest
697 memtest=0, mean disabled; -- default
698 memtest=1, mean do 1 test pattern;
700 memtest=4, mean do 4 test patterns.
701 If you are unsure how to answer this question, answer N.
703 config X86_SUMMIT_NUMA
705 depends on X86_32 && NUMA && X86_32_NON_STANDARD
707 config X86_CYCLONE_TIMER
709 depends on X86_SUMMIT
711 source "arch/x86/Kconfig.cpu"
715 prompt "HPET Timer Support" if X86_32
717 Use the IA-PC HPET (High Precision Event Timer) to manage
718 time in preference to the PIT and RTC, if a HPET is
720 HPET is the next generation timer replacing legacy 8254s.
721 The HPET provides a stable time base on SMP
722 systems, unlike the TSC, but it is more expensive to access,
723 as it is off-chip. You can find the HPET spec at
724 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
726 You can safely choose Y here. However, HPET will only be
727 activated if the platform and the BIOS support this feature.
728 Otherwise the 8254 will be used for timing services.
730 Choose N to continue using the legacy 8254 timer.
732 config HPET_EMULATE_RTC
734 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
737 def_bool y if X86_INTEL_MID
738 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
740 depends on X86_INTEL_MID && SFI
742 APB timer is the replacement for 8254, HPET on X86 MID platforms.
743 The APBT provides a stable time base on SMP
744 systems, unlike the TSC, but it is more expensive to access,
745 as it is off-chip. APB timers are always running regardless of CPU
746 C states, they are used as per CPU clockevent device when possible.
748 # Mark as expert because too many people got it wrong.
749 # The code disables itself when not needed.
752 bool "Enable DMI scanning" if EXPERT
754 Enabled scanning of DMI to identify machine quirks. Say Y
755 here unless you have verified that your setup is not
756 affected by entries in the DMI blacklist. Required by PNP
760 bool "Old AMD GART IOMMU support"
762 depends on X86_64 && PCI && AMD_NB
764 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
765 GART based hardware IOMMUs.
767 The GART supports full DMA access for devices with 32-bit access
768 limitations, on systems with more than 3 GB. This is usually needed
769 for USB, sound, many IDE/SATA chipsets and some other devices.
771 Newer systems typically have a modern AMD IOMMU, supported via
772 the CONFIG_AMD_IOMMU=y config option.
774 In normal configurations this driver is only active when needed:
775 there's more than 3 GB of memory and the system contains a
776 32-bit limited device.
781 bool "IBM Calgary IOMMU support"
783 depends on X86_64 && PCI
785 Support for hardware IOMMUs in IBM's xSeries x366 and x460
786 systems. Needed to run systems with more than 3GB of memory
787 properly with 32-bit PCI devices that do not support DAC
788 (Double Address Cycle). Calgary also supports bus level
789 isolation, where all DMAs pass through the IOMMU. This
790 prevents them from going anywhere except their intended
791 destination. This catches hard-to-find kernel bugs and
792 mis-behaving drivers and devices that do not use the DMA-API
793 properly to set up their DMA buffers. The IOMMU can be
794 turned off at boot time with the iommu=off parameter.
795 Normally the kernel will make the right choice by itself.
798 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
800 prompt "Should Calgary be enabled by default?"
801 depends on CALGARY_IOMMU
803 Should Calgary be enabled by default? if you choose 'y', Calgary
804 will be used (if it exists). If you choose 'n', Calgary will not be
805 used even if it exists. If you choose 'n' and would like to use
806 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
809 # need this always selected by IOMMU for the VIA workaround
813 Support for software bounce buffers used on x86-64 systems
814 which don't have a hardware IOMMU. Using this PCI devices
815 which can only access 32-bits of memory can be used on systems
816 with more than 3 GB of memory.
821 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
824 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
825 depends on X86_64 && SMP && DEBUG_KERNEL
826 select CPUMASK_OFFSTACK
828 Enable maximum number of CPUS and NUMA Nodes for this architecture.
832 int "Maximum number of CPUs" if SMP && !MAXSMP
833 range 2 8 if SMP && X86_32 && !X86_BIGSMP
834 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
835 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
837 default "8192" if MAXSMP
838 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
841 This allows you to specify the maximum number of CPUs which this
842 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
843 supported value is 4096, otherwise the maximum value is 512. The
844 minimum value which makes sense is 2.
846 This is purely to save memory - each supported CPU adds
847 approximately eight kilobytes to the kernel image.
850 bool "SMT (Hyperthreading) scheduler support"
853 SMT scheduler support improves the CPU scheduler's decision making
854 when dealing with Intel Pentium 4 chips with HyperThreading at a
855 cost of slightly increased overhead in some places. If unsure say
860 prompt "Multi-core scheduler support"
863 Multi-core scheduler support improves the CPU scheduler's decision
864 making when dealing with multi-core CPU chips at a cost of slightly
865 increased overhead in some places. If unsure say N here.
867 source "kernel/Kconfig.preempt"
870 bool "Local APIC support on uniprocessors"
871 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
873 A local APIC (Advanced Programmable Interrupt Controller) is an
874 integrated interrupt controller in the CPU. If you have a single-CPU
875 system which has a processor with a local APIC, you can say Y here to
876 enable and use it. If you say Y here even though your machine doesn't
877 have a local APIC, then the kernel will still run with no slowdown at
878 all. The local APIC supports CPU-generated self-interrupts (timer,
879 performance counters), and the NMI watchdog which detects hard
883 bool "IO-APIC support on uniprocessors"
884 depends on X86_UP_APIC
886 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
887 SMP-capable replacement for PC-style interrupt controllers. Most
888 SMP systems and many recent uniprocessor systems have one.
890 If you have a single-CPU system with an IO-APIC, you can say Y here
891 to use it. If you say Y here even though your machine doesn't have
892 an IO-APIC, then the kernel will still run with no slowdown at all.
894 config X86_LOCAL_APIC
896 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
900 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
902 config X86_VISWS_APIC
904 depends on X86_32 && X86_VISWS
906 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
907 bool "Reroute for broken boot IRQs"
908 depends on X86_IO_APIC
910 This option enables a workaround that fixes a source of
911 spurious interrupts. This is recommended when threaded
912 interrupt handling is used on systems where the generation of
913 superfluous "boot interrupts" cannot be disabled.
915 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
916 entry in the chipset's IO-APIC is masked (as, e.g. the RT
917 kernel does during interrupt handling). On chipsets where this
918 boot IRQ generation cannot be disabled, this workaround keeps
919 the original IRQ line masked so that only the equivalent "boot
920 IRQ" is delivered to the CPUs. The workaround also tells the
921 kernel to set up the IRQ handler on the boot IRQ line. In this
922 way only one interrupt is delivered to the kernel. Otherwise
923 the spurious second interrupt may cause the kernel to bring
924 down (vital) interrupt lines.
926 Only affects "broken" chipsets. Interrupt sharing may be
927 increased on these systems.
930 bool "Machine Check / overheating reporting"
933 Machine Check support allows the processor to notify the
934 kernel if it detects a problem (e.g. overheating, data corruption).
935 The action the kernel takes depends on the severity of the problem,
936 ranging from warning messages to halting the machine.
940 prompt "Intel MCE features"
941 depends on X86_MCE && X86_LOCAL_APIC
943 Additional support for intel specific MCE features such as
948 prompt "AMD MCE features"
949 depends on X86_MCE && X86_LOCAL_APIC
951 Additional support for AMD specific MCE features such as
952 the DRAM Error Threshold.
954 config X86_ANCIENT_MCE
955 bool "Support for old Pentium 5 / WinChip machine checks"
956 depends on X86_32 && X86_MCE
958 Include support for machine check handling on old Pentium 5 or WinChip
959 systems. These typically need to be enabled explicitely on the command
962 config X86_MCE_THRESHOLD
963 depends on X86_MCE_AMD || X86_MCE_INTEL
966 config X86_MCE_INJECT
968 tristate "Machine check injector support"
970 Provide support for injecting machine checks for testing purposes.
971 If you don't know what a machine check is and you don't do kernel
972 QA it is safe to say n.
974 config X86_THERMAL_VECTOR
976 depends on X86_MCE_INTEL
979 bool "Enable VM86 support" if EXPERT
983 This option is required by programs like DOSEMU to run 16-bit legacy
984 code on X86 processors. It also may be needed by software like
985 XFree86 to initialize some video cards via BIOS. Disabling this
986 option saves about 6k.
989 tristate "Toshiba Laptop support"
992 This adds a driver to safely access the System Management Mode of
993 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
994 not work on models with a Phoenix BIOS. The System Management Mode
995 is used to set the BIOS and power saving options on Toshiba portables.
997 For information on utilities to make use of this driver see the
998 Toshiba Linux utilities web site at:
999 <http://www.buzzard.org.uk/toshiba/>.
1001 Say Y if you intend to run this kernel on a Toshiba portable.
1005 tristate "Dell laptop support"
1008 This adds a driver to safely access the System Management Mode
1009 of the CPU on the Dell Inspiron 8000. The System Management Mode
1010 is used to read cpu temperature and cooling fan status and to
1011 control the fans on the I8K portables.
1013 This driver has been tested only on the Inspiron 8000 but it may
1014 also work with other Dell laptops. You can force loading on other
1015 models by passing the parameter `force=1' to the module. Use at
1018 For information on utilities to make use of this driver see the
1019 I8K Linux utilities web site at:
1020 <http://people.debian.org/~dz/i8k/>
1022 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1025 config X86_REBOOTFIXUPS
1026 bool "Enable X86 board specific fixups for reboot"
1029 This enables chipset and/or board specific fixups to be done
1030 in order to get reboot to work correctly. This is only needed on
1031 some combinations of hardware and BIOS. The symptom, for which
1032 this config is intended, is when reboot ends with a stalled/hung
1035 Currently, the only fixup is for the Geode machines using
1036 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1038 Say Y if you want to enable the fixup. Currently, it's safe to
1039 enable this option even if you don't need it.
1043 tristate "CPU microcode loading support"
1044 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1048 If you say Y here, you will be able to update the microcode on
1049 certain Intel and AMD processors. The Intel support is for the
1050 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1051 Xeon etc. The AMD support is for families 0x10 and later. You will
1052 obviously need the actual microcode binary data itself which is not
1053 shipped with the Linux kernel.
1055 This option selects the general module only, you need to select
1056 at least one vendor specific module as well.
1058 To compile this driver as a module, choose M here: the module
1059 will be called microcode.
1061 config MICROCODE_INTEL
1062 bool "Intel microcode loading support"
1063 depends on MICROCODE
1067 This options enables microcode patch loading support for Intel
1070 For latest news and information on obtaining all the required
1071 Intel ingredients for this driver, check:
1072 <http://www.urbanmyth.org/microcode/>.
1074 config MICROCODE_AMD
1075 bool "AMD microcode loading support"
1076 depends on MICROCODE
1079 If you select this option, microcode patch loading support for AMD
1080 processors will be enabled.
1082 config MICROCODE_OLD_INTERFACE
1084 depends on MICROCODE
1086 config MICROCODE_INTEL_LIB
1088 depends on MICROCODE_INTEL
1090 config MICROCODE_INTEL_EARLY
1093 config MICROCODE_AMD_EARLY
1096 config MICROCODE_EARLY
1097 bool "Early load microcode"
1098 depends on MICROCODE=y && BLK_DEV_INITRD
1099 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1100 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1103 This option provides functionality to read additional microcode data
1104 at the beginning of initrd image. The data tells kernel to load
1105 microcode to CPU's as early as possible. No functional change if no
1106 microcode data is glued to the initrd, therefore it's safe to say Y.
1109 tristate "/dev/cpu/*/msr - Model-specific register support"
1111 This device gives privileged processes access to the x86
1112 Model-Specific Registers (MSRs). It is a character device with
1113 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1114 MSR accesses are directed to a specific CPU on multi-processor
1118 tristate "/dev/cpu/*/cpuid - CPU information support"
1120 This device gives processes access to the x86 CPUID instruction to
1121 be executed on a specific processor. It is a character device
1122 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1126 prompt "High Memory Support"
1127 default HIGHMEM64G if X86_NUMAQ
1133 depends on !X86_NUMAQ
1135 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1136 However, the address space of 32-bit x86 processors is only 4
1137 Gigabytes large. That means that, if you have a large amount of
1138 physical memory, not all of it can be "permanently mapped" by the
1139 kernel. The physical memory that's not permanently mapped is called
1142 If you are compiling a kernel which will never run on a machine with
1143 more than 1 Gigabyte total physical RAM, answer "off" here (default
1144 choice and suitable for most users). This will result in a "3GB/1GB"
1145 split: 3GB are mapped so that each process sees a 3GB virtual memory
1146 space and the remaining part of the 4GB virtual memory space is used
1147 by the kernel to permanently map as much physical memory as
1150 If the machine has between 1 and 4 Gigabytes physical RAM, then
1153 If more than 4 Gigabytes is used then answer "64GB" here. This
1154 selection turns Intel PAE (Physical Address Extension) mode on.
1155 PAE implements 3-level paging on IA32 processors. PAE is fully
1156 supported by Linux, PAE mode is implemented on all recent Intel
1157 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1158 then the kernel will not boot on CPUs that don't support PAE!
1160 The actual amount of total physical memory will either be
1161 auto detected or can be forced by using a kernel command line option
1162 such as "mem=256M". (Try "man bootparam" or see the documentation of
1163 your boot loader (lilo or loadlin) about how to pass options to the
1164 kernel at boot time.)
1166 If unsure, say "off".
1170 depends on !X86_NUMAQ
1172 Select this if you have a 32-bit processor and between 1 and 4
1173 gigabytes of physical RAM.
1180 Select this if you have a 32-bit processor and more than 4
1181 gigabytes of physical RAM.
1186 prompt "Memory split" if EXPERT
1190 Select the desired split between kernel and user memory.
1192 If the address range available to the kernel is less than the
1193 physical memory installed, the remaining memory will be available
1194 as "high memory". Accessing high memory is a little more costly
1195 than low memory, as it needs to be mapped into the kernel first.
1196 Note that increasing the kernel address space limits the range
1197 available to user programs, making the address space there
1198 tighter. Selecting anything other than the default 3G/1G split
1199 will also likely make your kernel incompatible with binary-only
1202 If you are not absolutely sure what you are doing, leave this
1206 bool "3G/1G user/kernel split"
1207 config VMSPLIT_3G_OPT
1209 bool "3G/1G user/kernel split (for full 1G low memory)"
1211 bool "2G/2G user/kernel split"
1212 config VMSPLIT_2G_OPT
1214 bool "2G/2G user/kernel split (for full 2G low memory)"
1216 bool "1G/3G user/kernel split"
1221 default 0xB0000000 if VMSPLIT_3G_OPT
1222 default 0x80000000 if VMSPLIT_2G
1223 default 0x78000000 if VMSPLIT_2G_OPT
1224 default 0x40000000 if VMSPLIT_1G
1230 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1233 bool "PAE (Physical Address Extension) Support"
1234 depends on X86_32 && !HIGHMEM4G
1236 PAE is required for NX support, and furthermore enables
1237 larger swapspace support for non-overcommit purposes. It
1238 has the cost of more pagetable lookup overhead, and also
1239 consumes more pagetable space per process.
1241 config ARCH_PHYS_ADDR_T_64BIT
1243 depends on X86_64 || X86_PAE
1245 config ARCH_DMA_ADDR_T_64BIT
1247 depends on X86_64 || HIGHMEM64G
1249 config DIRECT_GBPAGES
1250 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1254 Allow the kernel linear mapping to use 1GB pages on CPUs that
1255 support it. This can improve the kernel's performance a tiny bit by
1256 reducing TLB pressure. If in doubt, say "Y".
1258 # Common NUMA Features
1260 bool "Numa Memory Allocation and Scheduler Support"
1262 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1263 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1265 Enable NUMA (Non Uniform Memory Access) support.
1267 The kernel will try to allocate memory used by a CPU on the
1268 local memory controller of the CPU and add some more
1269 NUMA awareness to the kernel.
1271 For 64-bit this is recommended if the system is Intel Core i7
1272 (or later), AMD Opteron, or EM64T NUMA.
1274 For 32-bit this is only needed on (rare) 32-bit-only platforms
1275 that support NUMA topologies, such as NUMAQ / Summit, or if you
1276 boot a 32-bit kernel on a 64-bit NUMA platform.
1278 Otherwise, you should say N.
1280 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1281 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1285 prompt "Old style AMD Opteron NUMA detection"
1286 depends on X86_64 && NUMA && PCI
1288 Enable AMD NUMA node topology detection. You should say Y here if
1289 you have a multi processor AMD system. This uses an old method to
1290 read the NUMA configuration directly from the builtin Northbridge
1291 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1292 which also takes priority if both are compiled in.
1294 config X86_64_ACPI_NUMA
1296 prompt "ACPI NUMA detection"
1297 depends on X86_64 && NUMA && ACPI && PCI
1300 Enable ACPI SRAT based node topology detection.
1302 # Some NUMA nodes have memory ranges that span
1303 # other nodes. Even though a pfn is valid and
1304 # between a node's start and end pfns, it may not
1305 # reside on that node. See memmap_init_zone()
1307 config NODES_SPAN_OTHER_NODES
1309 depends on X86_64_ACPI_NUMA
1312 bool "NUMA emulation"
1315 Enable NUMA emulation. A flat machine will be split
1316 into virtual nodes when booted with "numa=fake=N", where N is the
1317 number of nodes. This is only useful for debugging.
1320 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1322 default "10" if MAXSMP
1323 default "6" if X86_64
1324 default "4" if X86_NUMAQ
1326 depends on NEED_MULTIPLE_NODES
1328 Specify the maximum number of NUMA Nodes available on the target
1329 system. Increases memory reserved to accommodate various tables.
1331 config ARCH_HAVE_MEMORY_PRESENT
1333 depends on X86_32 && DISCONTIGMEM
1335 config NEED_NODE_MEMMAP_SIZE
1337 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1339 config ARCH_FLATMEM_ENABLE
1341 depends on X86_32 && !NUMA
1343 config ARCH_DISCONTIGMEM_ENABLE
1345 depends on NUMA && X86_32
1347 config ARCH_DISCONTIGMEM_DEFAULT
1349 depends on NUMA && X86_32
1351 config ARCH_SPARSEMEM_ENABLE
1353 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1354 select SPARSEMEM_STATIC if X86_32
1355 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1357 config ARCH_SPARSEMEM_DEFAULT
1361 config ARCH_SELECT_MEMORY_MODEL
1363 depends on ARCH_SPARSEMEM_ENABLE
1365 config ARCH_MEMORY_PROBE
1366 bool "Enable sysfs memory/probe interface"
1367 depends on X86_64 && MEMORY_HOTPLUG
1369 This option enables a sysfs memory/probe interface for testing.
1370 See Documentation/memory-hotplug.txt for more information.
1371 If you are unsure how to answer this question, answer N.
1373 config ARCH_PROC_KCORE_TEXT
1375 depends on X86_64 && PROC_KCORE
1377 config ILLEGAL_POINTER_VALUE
1380 default 0xdead000000000000 if X86_64
1385 bool "Allocate 3rd-level pagetables from highmem"
1388 The VM uses one page table entry for each page of physical memory.
1389 For systems with a lot of RAM, this can be wasteful of precious
1390 low memory. Setting this option will put user-space page table
1391 entries in high memory.
1393 config X86_CHECK_BIOS_CORRUPTION
1394 bool "Check for low memory corruption"
1396 Periodically check for memory corruption in low memory, which
1397 is suspected to be caused by BIOS. Even when enabled in the
1398 configuration, it is disabled at runtime. Enable it by
1399 setting "memory_corruption_check=1" on the kernel command
1400 line. By default it scans the low 64k of memory every 60
1401 seconds; see the memory_corruption_check_size and
1402 memory_corruption_check_period parameters in
1403 Documentation/kernel-parameters.txt to adjust this.
1405 When enabled with the default parameters, this option has
1406 almost no overhead, as it reserves a relatively small amount
1407 of memory and scans it infrequently. It both detects corruption
1408 and prevents it from affecting the running system.
1410 It is, however, intended as a diagnostic tool; if repeatable
1411 BIOS-originated corruption always affects the same memory,
1412 you can use memmap= to prevent the kernel from using that
1415 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1416 bool "Set the default setting of memory_corruption_check"
1417 depends on X86_CHECK_BIOS_CORRUPTION
1420 Set whether the default state of memory_corruption_check is
1423 config X86_RESERVE_LOW
1424 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1428 Specify the amount of low memory to reserve for the BIOS.
1430 The first page contains BIOS data structures that the kernel
1431 must not use, so that page must always be reserved.
1433 By default we reserve the first 64K of physical RAM, as a
1434 number of BIOSes are known to corrupt that memory range
1435 during events such as suspend/resume or monitor cable
1436 insertion, so it must not be used by the kernel.
1438 You can set this to 4 if you are absolutely sure that you
1439 trust the BIOS to get all its memory reservations and usages
1440 right. If you know your BIOS have problems beyond the
1441 default 64K area, you can set this to 640 to avoid using the
1442 entire low memory range.
1444 If you have doubts about the BIOS (e.g. suspend/resume does
1445 not work or there's kernel crashes after certain hardware
1446 hotplug events) then you might want to enable
1447 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1448 typical corruption patterns.
1450 Leave this to the default value of 64 if you are unsure.
1452 config MATH_EMULATION
1454 prompt "Math emulation" if X86_32
1456 Linux can emulate a math coprocessor (used for floating point
1457 operations) if you don't have one. 486DX and Pentium processors have
1458 a math coprocessor built in, 486SX and 386 do not, unless you added
1459 a 487DX or 387, respectively. (The messages during boot time can
1460 give you some hints here ["man dmesg"].) Everyone needs either a
1461 coprocessor or this emulation.
1463 If you don't have a math coprocessor, you need to say Y here; if you
1464 say Y here even though you have a coprocessor, the coprocessor will
1465 be used nevertheless. (This behavior can be changed with the kernel
1466 command line option "no387", which comes handy if your coprocessor
1467 is broken. Try "man bootparam" or see the documentation of your boot
1468 loader (lilo or loadlin) about how to pass options to the kernel at
1469 boot time.) This means that it is a good idea to say Y here if you
1470 intend to use this kernel on different machines.
1472 More information about the internals of the Linux math coprocessor
1473 emulation can be found in <file:arch/x86/math-emu/README>.
1475 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1476 kernel, it won't hurt.
1480 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1482 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1483 the Memory Type Range Registers (MTRRs) may be used to control
1484 processor access to memory ranges. This is most useful if you have
1485 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1486 allows bus write transfers to be combined into a larger transfer
1487 before bursting over the PCI/AGP bus. This can increase performance
1488 of image write operations 2.5 times or more. Saying Y here creates a
1489 /proc/mtrr file which may be used to manipulate your processor's
1490 MTRRs. Typically the X server should use this.
1492 This code has a reasonably generic interface so that similar
1493 control registers on other processors can be easily supported
1496 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1497 Registers (ARRs) which provide a similar functionality to MTRRs. For
1498 these, the ARRs are used to emulate the MTRRs.
1499 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1500 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1501 write-combining. All of these processors are supported by this code
1502 and it makes sense to say Y here if you have one of them.
1504 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1505 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1506 can lead to all sorts of problems, so it's good to say Y here.
1508 You can safely say Y even if your machine doesn't have MTRRs, you'll
1509 just add about 9 KB to your kernel.
1511 See <file:Documentation/x86/mtrr.txt> for more information.
1513 config MTRR_SANITIZER
1515 prompt "MTRR cleanup support"
1518 Convert MTRR layout from continuous to discrete, so X drivers can
1519 add writeback entries.
1521 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1522 The largest mtrr entry size for a continuous block can be set with
1527 config MTRR_SANITIZER_ENABLE_DEFAULT
1528 int "MTRR cleanup enable value (0-1)"
1531 depends on MTRR_SANITIZER
1533 Enable mtrr cleanup default value
1535 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1536 int "MTRR cleanup spare reg num (0-7)"
1539 depends on MTRR_SANITIZER
1541 mtrr cleanup spare entries default, it can be changed via
1542 mtrr_spare_reg_nr=N on the kernel command line.
1546 prompt "x86 PAT support" if EXPERT
1549 Use PAT attributes to setup page level cache control.
1551 PATs are the modern equivalents of MTRRs and are much more
1552 flexible than MTRRs.
1554 Say N here if you see bootup problems (boot crash, boot hang,
1555 spontaneous reboots) or a non-working video driver.
1559 config ARCH_USES_PG_UNCACHED
1565 prompt "x86 architectural random number generator" if EXPERT
1567 Enable the x86 architectural RDRAND instruction
1568 (Intel Bull Mountain technology) to generate random numbers.
1569 If supported, this is a high bandwidth, cryptographically
1570 secure hardware random number generator.
1574 prompt "Supervisor Mode Access Prevention" if EXPERT
1576 Supervisor Mode Access Prevention (SMAP) is a security
1577 feature in newer Intel processors. There is a small
1578 performance cost if this enabled and turned on; there is
1579 also a small increase in the kernel size if this is enabled.
1584 bool "EFI runtime service support"
1588 This enables the kernel to use EFI runtime services that are
1589 available (such as the EFI variable services).
1591 This option is only useful on systems that have EFI firmware.
1592 In addition, you should use the latest ELILO loader available
1593 at <http://elilo.sourceforge.net> in order to take advantage
1594 of EFI runtime services. However, even with this option, the
1595 resultant kernel should continue to boot on existing non-EFI
1599 bool "EFI stub support"
1602 This kernel feature allows a bzImage to be loaded directly
1603 by EFI firmware without the use of a bootloader.
1605 See Documentation/efi-stub.txt for more information.
1609 prompt "Enable seccomp to safely compute untrusted bytecode"
1611 This kernel feature is useful for number crunching applications
1612 that may need to compute untrusted bytecode during their
1613 execution. By using pipes or other transports made available to
1614 the process as file descriptors supporting the read/write
1615 syscalls, it's possible to isolate those applications in
1616 their own address space using seccomp. Once seccomp is
1617 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1618 and the task is only allowed to execute a few safe syscalls
1619 defined by each seccomp mode.
1621 If unsure, say Y. Only embedded should say N here.
1623 config CC_STACKPROTECTOR
1624 bool "Enable -fstack-protector buffer overflow detection"
1626 This option turns on the -fstack-protector GCC feature. This
1627 feature puts, at the beginning of functions, a canary value on
1628 the stack just before the return address, and validates
1629 the value just before actually returning. Stack based buffer
1630 overflows (that need to overwrite this return address) now also
1631 overwrite the canary, which gets detected and the attack is then
1632 neutralized via a kernel panic.
1634 This feature requires gcc version 4.2 or above, or a distribution
1635 gcc with the feature backported. Older versions are automatically
1636 detected and for those versions, this configuration option is
1637 ignored. (and a warning is printed during bootup)
1639 source kernel/Kconfig.hz
1642 bool "kexec system call"
1644 kexec is a system call that implements the ability to shutdown your
1645 current kernel, and to start another kernel. It is like a reboot
1646 but it is independent of the system firmware. And like a reboot
1647 you can start any kernel with it, not just Linux.
1649 The name comes from the similarity to the exec system call.
1651 It is an ongoing process to be certain the hardware in a machine
1652 is properly shutdown, so do not be surprised if this code does not
1653 initially work for you. As of this writing the exact hardware
1654 interface is strongly in flux, so no good recommendation can be
1658 bool "kernel crash dumps"
1659 depends on X86_64 || (X86_32 && HIGHMEM)
1661 Generate crash dump after being started by kexec.
1662 This should be normally only set in special crash dump kernels
1663 which are loaded in the main kernel with kexec-tools into
1664 a specially reserved region and then later executed after
1665 a crash by kdump/kexec. The crash dump kernel must be compiled
1666 to a memory address not used by the main kernel or BIOS using
1667 PHYSICAL_START, or it must be built as a relocatable image
1668 (CONFIG_RELOCATABLE=y).
1669 For more details see Documentation/kdump/kdump.txt
1673 depends on KEXEC && HIBERNATION
1675 Jump between original kernel and kexeced kernel and invoke
1676 code in physical address mode via KEXEC
1678 config PHYSICAL_START
1679 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1682 This gives the physical address where the kernel is loaded.
1684 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1685 bzImage will decompress itself to above physical address and
1686 run from there. Otherwise, bzImage will run from the address where
1687 it has been loaded by the boot loader and will ignore above physical
1690 In normal kdump cases one does not have to set/change this option
1691 as now bzImage can be compiled as a completely relocatable image
1692 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1693 address. This option is mainly useful for the folks who don't want
1694 to use a bzImage for capturing the crash dump and want to use a
1695 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1696 to be specifically compiled to run from a specific memory area
1697 (normally a reserved region) and this option comes handy.
1699 So if you are using bzImage for capturing the crash dump,
1700 leave the value here unchanged to 0x1000000 and set
1701 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1702 for capturing the crash dump change this value to start of
1703 the reserved region. In other words, it can be set based on
1704 the "X" value as specified in the "crashkernel=YM@XM"
1705 command line boot parameter passed to the panic-ed
1706 kernel. Please take a look at Documentation/kdump/kdump.txt
1707 for more details about crash dumps.
1709 Usage of bzImage for capturing the crash dump is recommended as
1710 one does not have to build two kernels. Same kernel can be used
1711 as production kernel and capture kernel. Above option should have
1712 gone away after relocatable bzImage support is introduced. But it
1713 is present because there are users out there who continue to use
1714 vmlinux for dump capture. This option should go away down the
1717 Don't change this unless you know what you are doing.
1720 bool "Build a relocatable kernel"
1723 This builds a kernel image that retains relocation information
1724 so it can be loaded someplace besides the default 1MB.
1725 The relocations tend to make the kernel binary about 10% larger,
1726 but are discarded at runtime.
1728 One use is for the kexec on panic case where the recovery kernel
1729 must live at a different physical address than the primary
1732 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1733 it has been loaded at and the compile time physical address
1734 (CONFIG_PHYSICAL_START) is ignored.
1736 # Relocation on x86-32 needs some additional build support
1737 config X86_NEED_RELOCS
1739 depends on X86_32 && RELOCATABLE
1741 config PHYSICAL_ALIGN
1742 hex "Alignment value to which kernel should be aligned"
1744 range 0x2000 0x1000000 if X86_32
1745 range 0x200000 0x1000000 if X86_64
1747 This value puts the alignment restrictions on physical address
1748 where kernel is loaded and run from. Kernel is compiled for an
1749 address which meets above alignment restriction.
1751 If bootloader loads the kernel at a non-aligned address and
1752 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1753 address aligned to above value and run from there.
1755 If bootloader loads the kernel at a non-aligned address and
1756 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1757 load address and decompress itself to the address it has been
1758 compiled for and run from there. The address for which kernel is
1759 compiled already meets above alignment restrictions. Hence the
1760 end result is that kernel runs from a physical address meeting
1761 above alignment restrictions.
1763 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1764 this value must be a multiple of 0x200000.
1766 Don't change this unless you know what you are doing.
1769 bool "Support for hot-pluggable CPUs"
1772 Say Y here to allow turning CPUs off and on. CPUs can be
1773 controlled through /sys/devices/system/cpu.
1774 ( Note: power management support will enable this option
1775 automatically on SMP systems. )
1776 Say N if you want to disable CPU hotplug.
1778 config BOOTPARAM_HOTPLUG_CPU0
1779 bool "Set default setting of cpu0_hotpluggable"
1781 depends on HOTPLUG_CPU
1783 Set whether default state of cpu0_hotpluggable is on or off.
1785 Say Y here to enable CPU0 hotplug by default. If this switch
1786 is turned on, there is no need to give cpu0_hotplug kernel
1787 parameter and the CPU0 hotplug feature is enabled by default.
1789 Please note: there are two known CPU0 dependencies if you want
1790 to enable the CPU0 hotplug feature either by this switch or by
1791 cpu0_hotplug kernel parameter.
1793 First, resume from hibernate or suspend always starts from CPU0.
1794 So hibernate and suspend are prevented if CPU0 is offline.
1796 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1797 offline if any interrupt can not migrate out of CPU0. There may
1798 be other CPU0 dependencies.
1800 Please make sure the dependencies are under your control before
1801 you enable this feature.
1803 Say N if you don't want to enable CPU0 hotplug feature by default.
1804 You still can enable the CPU0 hotplug feature at boot by kernel
1805 parameter cpu0_hotplug.
1807 config DEBUG_HOTPLUG_CPU0
1809 prompt "Debug CPU0 hotplug"
1810 depends on HOTPLUG_CPU
1812 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1813 soon as possible and boots up userspace with CPU0 offlined. User
1814 can online CPU0 back after boot time.
1816 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1817 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1818 compilation or giving cpu0_hotplug kernel parameter at boot.
1824 prompt "Compat VDSO support"
1825 depends on X86_32 || IA32_EMULATION
1827 Map the 32-bit VDSO to the predictable old-style address too.
1829 Say N here if you are running a sufficiently recent glibc
1830 version (2.3.3 or later), to remove the high-mapped
1831 VDSO mapping and to exclusively use the randomized VDSO.
1836 bool "Built-in kernel command line"
1838 Allow for specifying boot arguments to the kernel at
1839 build time. On some systems (e.g. embedded ones), it is
1840 necessary or convenient to provide some or all of the
1841 kernel boot arguments with the kernel itself (that is,
1842 to not rely on the boot loader to provide them.)
1844 To compile command line arguments into the kernel,
1845 set this option to 'Y', then fill in the
1846 the boot arguments in CONFIG_CMDLINE.
1848 Systems with fully functional boot loaders (i.e. non-embedded)
1849 should leave this option set to 'N'.
1852 string "Built-in kernel command string"
1853 depends on CMDLINE_BOOL
1856 Enter arguments here that should be compiled into the kernel
1857 image and used at boot time. If the boot loader provides a
1858 command line at boot time, it is appended to this string to
1859 form the full kernel command line, when the system boots.
1861 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1862 change this behavior.
1864 In most cases, the command line (whether built-in or provided
1865 by the boot loader) should specify the device for the root
1868 config CMDLINE_OVERRIDE
1869 bool "Built-in command line overrides boot loader arguments"
1870 depends on CMDLINE_BOOL
1872 Set this option to 'Y' to have the kernel ignore the boot loader
1873 command line, and use ONLY the built-in command line.
1875 This is used to work around broken boot loaders. This should
1876 be set to 'N' under normal conditions.
1880 config ARCH_ENABLE_MEMORY_HOTPLUG
1882 depends on X86_64 || (X86_32 && HIGHMEM)
1884 config ARCH_ENABLE_MEMORY_HOTREMOVE
1886 depends on MEMORY_HOTPLUG
1888 config USE_PERCPU_NUMA_NODE_ID
1892 menu "Power management and ACPI options"
1894 config ARCH_HIBERNATION_HEADER
1896 depends on X86_64 && HIBERNATION
1898 source "kernel/power/Kconfig"
1900 source "drivers/acpi/Kconfig"
1902 source "drivers/sfi/Kconfig"
1909 tristate "APM (Advanced Power Management) BIOS support"
1910 depends on X86_32 && PM_SLEEP
1912 APM is a BIOS specification for saving power using several different
1913 techniques. This is mostly useful for battery powered laptops with
1914 APM compliant BIOSes. If you say Y here, the system time will be
1915 reset after a RESUME operation, the /proc/apm device will provide
1916 battery status information, and user-space programs will receive
1917 notification of APM "events" (e.g. battery status change).
1919 If you select "Y" here, you can disable actual use of the APM
1920 BIOS by passing the "apm=off" option to the kernel at boot time.
1922 Note that the APM support is almost completely disabled for
1923 machines with more than one CPU.
1925 In order to use APM, you will need supporting software. For location
1926 and more information, read <file:Documentation/power/apm-acpi.txt>
1927 and the Battery Powered Linux mini-HOWTO, available from
1928 <http://www.tldp.org/docs.html#howto>.
1930 This driver does not spin down disk drives (see the hdparm(8)
1931 manpage ("man 8 hdparm") for that), and it doesn't turn off
1932 VESA-compliant "green" monitors.
1934 This driver does not support the TI 4000M TravelMate and the ACER
1935 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1936 desktop machines also don't have compliant BIOSes, and this driver
1937 may cause those machines to panic during the boot phase.
1939 Generally, if you don't have a battery in your machine, there isn't
1940 much point in using this driver and you should say N. If you get
1941 random kernel OOPSes or reboots that don't seem to be related to
1942 anything, try disabling/enabling this option (or disabling/enabling
1945 Some other things you should try when experiencing seemingly random,
1948 1) make sure that you have enough swap space and that it is
1950 2) pass the "no-hlt" option to the kernel
1951 3) switch on floating point emulation in the kernel and pass
1952 the "no387" option to the kernel
1953 4) pass the "floppy=nodma" option to the kernel
1954 5) pass the "mem=4M" option to the kernel (thereby disabling
1955 all but the first 4 MB of RAM)
1956 6) make sure that the CPU is not over clocked.
1957 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1958 8) disable the cache from your BIOS settings
1959 9) install a fan for the video card or exchange video RAM
1960 10) install a better fan for the CPU
1961 11) exchange RAM chips
1962 12) exchange the motherboard.
1964 To compile this driver as a module, choose M here: the
1965 module will be called apm.
1969 config APM_IGNORE_USER_SUSPEND
1970 bool "Ignore USER SUSPEND"
1972 This option will ignore USER SUSPEND requests. On machines with a
1973 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1974 series notebooks, it is necessary to say Y because of a BIOS bug.
1976 config APM_DO_ENABLE
1977 bool "Enable PM at boot time"
1979 Enable APM features at boot time. From page 36 of the APM BIOS
1980 specification: "When disabled, the APM BIOS does not automatically
1981 power manage devices, enter the Standby State, enter the Suspend
1982 State, or take power saving steps in response to CPU Idle calls."
1983 This driver will make CPU Idle calls when Linux is idle (unless this
1984 feature is turned off -- see "Do CPU IDLE calls", below). This
1985 should always save battery power, but more complicated APM features
1986 will be dependent on your BIOS implementation. You may need to turn
1987 this option off if your computer hangs at boot time when using APM
1988 support, or if it beeps continuously instead of suspending. Turn
1989 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1990 T400CDT. This is off by default since most machines do fine without
1995 bool "Make CPU Idle calls when idle"
1997 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1998 On some machines, this can activate improved power savings, such as
1999 a slowed CPU clock rate, when the machine is idle. These idle calls
2000 are made after the idle loop has run for some length of time (e.g.,
2001 333 mS). On some machines, this will cause a hang at boot time or
2002 whenever the CPU becomes idle. (On machines with more than one CPU,
2003 this option does nothing.)
2005 config APM_DISPLAY_BLANK
2006 bool "Enable console blanking using APM"
2008 Enable console blanking using the APM. Some laptops can use this to
2009 turn off the LCD backlight when the screen blanker of the Linux
2010 virtual console blanks the screen. Note that this is only used by
2011 the virtual console screen blanker, and won't turn off the backlight
2012 when using the X Window system. This also doesn't have anything to
2013 do with your VESA-compliant power-saving monitor. Further, this
2014 option doesn't work for all laptops -- it might not turn off your
2015 backlight at all, or it might print a lot of errors to the console,
2016 especially if you are using gpm.
2018 config APM_ALLOW_INTS
2019 bool "Allow interrupts during APM BIOS calls"
2021 Normally we disable external interrupts while we are making calls to
2022 the APM BIOS as a measure to lessen the effects of a badly behaving
2023 BIOS implementation. The BIOS should reenable interrupts if it
2024 needs to. Unfortunately, some BIOSes do not -- especially those in
2025 many of the newer IBM Thinkpads. If you experience hangs when you
2026 suspend, try setting this to Y. Otherwise, say N.
2030 source "drivers/cpufreq/Kconfig"
2032 source "drivers/cpuidle/Kconfig"
2034 source "drivers/idle/Kconfig"
2039 menu "Bus options (PCI etc.)"
2045 Find out whether you have a PCI motherboard. PCI is the name of a
2046 bus system, i.e. the way the CPU talks to the other stuff inside
2047 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2048 VESA. If you have PCI, say Y, otherwise N.
2051 prompt "PCI access mode"
2052 depends on X86_32 && PCI
2055 On PCI systems, the BIOS can be used to detect the PCI devices and
2056 determine their configuration. However, some old PCI motherboards
2057 have BIOS bugs and may crash if this is done. Also, some embedded
2058 PCI-based systems don't have any BIOS at all. Linux can also try to
2059 detect the PCI hardware directly without using the BIOS.
2061 With this option, you can specify how Linux should detect the
2062 PCI devices. If you choose "BIOS", the BIOS will be used,
2063 if you choose "Direct", the BIOS won't be used, and if you
2064 choose "MMConfig", then PCI Express MMCONFIG will be used.
2065 If you choose "Any", the kernel will try MMCONFIG, then the
2066 direct access method and falls back to the BIOS if that doesn't
2067 work. If unsure, go with the default, which is "Any".
2072 config PCI_GOMMCONFIG
2089 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2091 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2094 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2098 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2102 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2106 depends on PCI && XEN
2114 bool "Support mmconfig PCI config space access"
2115 depends on X86_64 && PCI && ACPI
2117 config PCI_CNB20LE_QUIRK
2118 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2121 Read the PCI windows out of the CNB20LE host bridge. This allows
2122 PCI hotplug to work on systems with the CNB20LE chipset which do
2125 There's no public spec for this chipset, and this functionality
2126 is known to be incomplete.
2128 You should say N unless you know you need this.
2130 source "drivers/pci/pcie/Kconfig"
2132 source "drivers/pci/Kconfig"
2134 # x86_64 have no ISA slots, but can have ISA-style DMA.
2136 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2139 Enables ISA-style DMA support for devices requiring such controllers.
2147 Find out whether you have ISA slots on your motherboard. ISA is the
2148 name of a bus system, i.e. the way the CPU talks to the other stuff
2149 inside your box. Other bus systems are PCI, EISA, MicroChannel
2150 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2151 newer boards don't support it. If you have ISA, say Y, otherwise N.
2157 The Extended Industry Standard Architecture (EISA) bus was
2158 developed as an open alternative to the IBM MicroChannel bus.
2160 The EISA bus provided some of the features of the IBM MicroChannel
2161 bus while maintaining backward compatibility with cards made for
2162 the older ISA bus. The EISA bus saw limited use between 1988 and
2163 1995 when it was made obsolete by the PCI bus.
2165 Say Y here if you are building a kernel for an EISA-based machine.
2169 source "drivers/eisa/Kconfig"
2172 tristate "NatSemi SCx200 support"
2174 This provides basic support for National Semiconductor's
2175 (now AMD's) Geode processors. The driver probes for the
2176 PCI-IDs of several on-chip devices, so its a good dependency
2177 for other scx200_* drivers.
2179 If compiled as a module, the driver is named scx200.
2181 config SCx200HR_TIMER
2182 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2186 This driver provides a clocksource built upon the on-chip
2187 27MHz high-resolution timer. Its also a workaround for
2188 NSC Geode SC-1100's buggy TSC, which loses time when the
2189 processor goes idle (as is done by the scheduler). The
2190 other workaround is idle=poll boot option.
2193 bool "One Laptop Per Child support"
2200 Add support for detecting the unique features of the OLPC
2204 bool "OLPC XO-1 Power Management"
2205 depends on OLPC && MFD_CS5535 && PM_SLEEP
2208 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2211 bool "OLPC XO-1 Real Time Clock"
2212 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2214 Add support for the XO-1 real time clock, which can be used as a
2215 programmable wakeup source.
2218 bool "OLPC XO-1 SCI extras"
2219 depends on OLPC && OLPC_XO1_PM
2225 Add support for SCI-based features of the OLPC XO-1 laptop:
2226 - EC-driven system wakeups
2230 - AC adapter status updates
2231 - Battery status updates
2233 config OLPC_XO15_SCI
2234 bool "OLPC XO-1.5 SCI extras"
2235 depends on OLPC && ACPI
2238 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2239 - EC-driven system wakeups
2240 - AC adapter status updates
2241 - Battery status updates
2244 bool "PCEngines ALIX System Support (LED setup)"
2247 This option enables system support for the PCEngines ALIX.
2248 At present this just sets up LEDs for GPIO control on
2249 ALIX2/3/6 boards. However, other system specific setup should
2252 Note: You must still enable the drivers for GPIO and LED support
2253 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2255 Note: You have to set alix.force=1 for boards with Award BIOS.
2258 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2261 This option enables system support for the Soekris Engineering net5501.
2264 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2268 This option enables system support for the Traverse Technologies GEOS.
2271 bool "Technologic Systems TS-5500 platform support"
2273 select CHECK_SIGNATURE
2277 This option enables system support for the Technologic Systems TS-5500.
2283 depends on CPU_SUP_AMD && PCI
2285 source "drivers/pcmcia/Kconfig"
2287 source "drivers/pci/hotplug/Kconfig"
2290 tristate "RapidIO support"
2294 If enabled this option will include drivers and the core
2295 infrastructure code to support RapidIO interconnect devices.
2297 source "drivers/rapidio/Kconfig"
2300 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2302 Firmwares often provide initial graphics framebuffers so the BIOS,
2303 bootloader or kernel can show basic video-output during boot for
2304 user-guidance and debugging. Historically, x86 used the VESA BIOS
2305 Extensions and EFI-framebuffers for this, which are mostly limited
2307 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2308 framebuffers so the new generic system-framebuffer drivers can be
2309 used on x86. If the framebuffer is not compatible with the generic
2310 modes, it is adverticed as fallback platform framebuffer so legacy
2311 drivers like efifb, vesafb and uvesafb can pick it up.
2312 If this option is not selected, all system framebuffers are always
2313 marked as fallback platform framebuffers as usual.
2315 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2316 not be able to pick up generic system framebuffers if this option
2317 is selected. You are highly encouraged to enable simplefb as
2318 replacement if you select this option. simplefb can correctly deal
2319 with generic system framebuffers. But you should still keep vesafb
2320 and others enabled as fallback if a system framebuffer is
2321 incompatible with simplefb.
2328 menu "Executable file formats / Emulations"
2330 source "fs/Kconfig.binfmt"
2332 config IA32_EMULATION
2333 bool "IA32 Emulation"
2336 select COMPAT_BINFMT_ELF
2339 Include code to run legacy 32-bit programs under a
2340 64-bit kernel. You should likely turn this on, unless you're
2341 100% sure that you don't have any 32-bit programs left.
2344 tristate "IA32 a.out support"
2345 depends on IA32_EMULATION
2347 Support old a.out binaries in the 32bit emulation.
2350 bool "x32 ABI for 64-bit mode"
2351 depends on X86_64 && IA32_EMULATION
2353 Include code to run binaries for the x32 native 32-bit ABI
2354 for 64-bit processors. An x32 process gets access to the
2355 full 64-bit register file and wide data path while leaving
2356 pointers at 32 bits for smaller memory footprint.
2358 You will need a recent binutils (2.22 or later) with
2359 elf32_x86_64 support enabled to compile a kernel with this
2364 depends on IA32_EMULATION || X86_X32
2365 select ARCH_WANT_OLD_COMPAT_IPC
2368 config COMPAT_FOR_U64_ALIGNMENT
2371 config SYSVIPC_COMPAT
2383 config HAVE_ATOMIC_IOMAP
2387 config X86_DEV_DMA_OPS
2389 depends on X86_64 || STA2X11
2391 config X86_DMA_REMAP
2395 source "net/Kconfig"
2397 source "drivers/Kconfig"
2399 source "drivers/firmware/Kconfig"
2403 source "arch/x86/Kconfig.debug"
2405 source "security/Kconfig"
2407 source "crypto/Kconfig"
2409 source "arch/x86/kvm/Kconfig"
2411 source "lib/Kconfig"