x86: Add IRQ_TIME_ACCOUNTING

[mirror_ubuntu-artful-kernel.git] / arch / x86 / Kconfig

# x86 configuration
mainmenu "Linux Kernel Configuration for x86"

# Select 32 or 64 bit
config 64BIT
        bool "64-bit kernel" if ARCH = "x86"
        default ARCH = "x86_64"
        ---help---
          Say yes to build a 64-bit kernel - formerly known as x86_64
          Say no to build a 32-bit kernel - formerly known as i386

config X86_32
        def_bool !64BIT

config X86_64
        def_bool 64BIT

### Arch settings
config X86
        def_bool y
        select HAVE_AOUT if X86_32
        select HAVE_READQ
        select HAVE_WRITEQ
        select HAVE_UNSTABLE_SCHED_CLOCK
        select HAVE_IDE
        select HAVE_OPROFILE
        select HAVE_PERF_EVENTS if (!M386 && !M486)
        select HAVE_IOREMAP_PROT
        select HAVE_KPROBES
        select ARCH_WANT_OPTIONAL_GPIOLIB
        select ARCH_WANT_FRAME_POINTERS
        select HAVE_DMA_ATTRS
        select HAVE_KRETPROBES
        select HAVE_OPTPROBES
        select HAVE_FTRACE_MCOUNT_RECORD
        select HAVE_DYNAMIC_FTRACE
        select HAVE_FUNCTION_TRACER
        select HAVE_FUNCTION_GRAPH_TRACER
        select HAVE_FUNCTION_GRAPH_FP_TEST
        select HAVE_FUNCTION_TRACE_MCOUNT_TEST
        select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
        select HAVE_SYSCALL_TRACEPOINTS
        select HAVE_KVM
        select HAVE_ARCH_KGDB
        select HAVE_ARCH_TRACEHOOK
        select HAVE_GENERIC_DMA_COHERENT if X86_32
        select HAVE_EFFICIENT_UNALIGNED_ACCESS
        select USER_STACKTRACE_SUPPORT
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_DMA_API_DEBUG
        select HAVE_KERNEL_GZIP
        select HAVE_KERNEL_BZIP2
        select HAVE_KERNEL_LZMA
        select HAVE_KERNEL_LZO
        select HAVE_HW_BREAKPOINT
        select HAVE_MIXED_BREAKPOINTS_REGS
        select PERF_EVENTS
        select HAVE_PERF_EVENTS_NMI
        select ANON_INODES
        select HAVE_ARCH_KMEMCHECK
        select HAVE_USER_RETURN_NOTIFIER

config INSTRUCTION_DECODER
        def_bool (KPROBES || PERF_EVENTS)

config OUTPUT_FORMAT
        string
        default "elf32-i386" if X86_32
        default "elf64-x86-64" if X86_64

config ARCH_DEFCONFIG
        string
        default "arch/x86/configs/i386_defconfig" if X86_32
        default "arch/x86/configs/x86_64_defconfig" if X86_64

config GENERIC_CMOS_UPDATE
        def_bool y

config CLOCKSOURCE_WATCHDOG
        def_bool y

config GENERIC_CLOCKEVENTS
        def_bool y

config GENERIC_CLOCKEVENTS_BROADCAST
        def_bool y
        depends on X86_64 || (X86_32 && X86_LOCAL_APIC)

config LOCKDEP_SUPPORT
        def_bool y

config STACKTRACE_SUPPORT
        def_bool y

config HAVE_LATENCYTOP_SUPPORT
        def_bool y

config MMU
        def_bool y

config ZONE_DMA
        def_bool y

config SBUS
        bool

config NEED_DMA_MAP_STATE
       def_bool (X86_64 || DMAR || DMA_API_DEBUG)

config NEED_SG_DMA_LENGTH
        def_bool y

config GENERIC_ISA_DMA
        def_bool y

config GENERIC_IOMAP
        def_bool y

config GENERIC_BUG
        def_bool y
        depends on BUG
        select GENERIC_BUG_RELATIVE_POINTERS if X86_64

config GENERIC_BUG_RELATIVE_POINTERS
        bool

config GENERIC_HWEIGHT
        def_bool y

config GENERIC_GPIO
        bool

config ARCH_MAY_HAVE_PC_FDC
        def_bool y

config RWSEM_GENERIC_SPINLOCK
        def_bool !X86_XADD

config RWSEM_XCHGADD_ALGORITHM
        def_bool X86_XADD

config ARCH_HAS_CPU_IDLE_WAIT
        def_bool y

config GENERIC_CALIBRATE_DELAY
        def_bool y

config GENERIC_TIME_VSYSCALL
        bool
        default X86_64

config ARCH_HAS_CPU_RELAX
        def_bool y

config ARCH_HAS_DEFAULT_IDLE
        def_bool y

config ARCH_HAS_CACHE_LINE_SIZE
        def_bool y

config HAVE_SETUP_PER_CPU_AREA
        def_bool y

config NEED_PER_CPU_EMBED_FIRST_CHUNK
        def_bool y

config NEED_PER_CPU_PAGE_FIRST_CHUNK
        def_bool y

config HAVE_CPUMASK_OF_CPU_MAP
        def_bool X86_64_SMP

config ARCH_HIBERNATION_POSSIBLE
        def_bool y

config ARCH_SUSPEND_POSSIBLE
        def_bool y

config ZONE_DMA32
        bool
        default X86_64

config ARCH_POPULATES_NODE_MAP
        def_bool y

config AUDIT_ARCH
        bool
        default X86_64

config ARCH_SUPPORTS_OPTIMIZED_INLINING
        def_bool y

config ARCH_SUPPORTS_DEBUG_PAGEALLOC
        def_bool y

config HAVE_EARLY_RES
        def_bool y

config HAVE_INTEL_TXT
        def_bool y
        depends on EXPERIMENTAL && DMAR && ACPI

# Use the generic interrupt handling code in kernel/irq/:
config GENERIC_HARDIRQS
        def_bool y

config GENERIC_HARDIRQS_NO__DO_IRQ
       def_bool y

config GENERIC_IRQ_PROBE
        def_bool y

config GENERIC_PENDING_IRQ
        def_bool y
        depends on GENERIC_HARDIRQS && SMP

config USE_GENERIC_SMP_HELPERS
        def_bool y
        depends on SMP

config X86_32_SMP
        def_bool y
        depends on X86_32 && SMP

config X86_64_SMP
        def_bool y
        depends on X86_64 && SMP

config X86_HT
        def_bool y
        depends on SMP

config X86_TRAMPOLINE
        def_bool y
        depends on SMP || (64BIT && ACPI_SLEEP)

config X86_32_LAZY_GS
        def_bool y
        depends on X86_32 && !CC_STACKPROTECTOR

config ARCH_HWEIGHT_CFLAGS
        string
        default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
        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

config KTIME_SCALAR
        def_bool X86_32

config ARCH_CPU_PROBE_RELEASE
        def_bool y
        depends on HOTPLUG_CPU

source "init/Kconfig"
source "kernel/Kconfig.freezer"

menu "Processor type and features"

source "kernel/time/Kconfig"

config SMP
        bool "Symmetric multi-processing support"
        ---help---
          This enables support for systems with more than one CPU. If you have
          a system with only one CPU, like most personal computers, say N. If
          you have a system with more than one CPU, say Y.

          If you say N here, the kernel will run on single and multiprocessor
          machines, but will use only one CPU of a multiprocessor machine. If
          you say Y here, the kernel will run on many, but not all,
          singleprocessor machines. On a singleprocessor machine, the kernel
          will run faster if you say N here.

          Note that if you say Y here and choose architecture "586" or
          "Pentium" under "Processor family", the kernel will not work on 486
          architectures. Similarly, multiprocessor kernels for the "PPro"
          architecture may not work on all Pentium based boards.

          People using multiprocessor machines who say Y here should also say
          Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
          Management" code will be disabled if you say Y here.

          See also <file:Documentation/i386/IO-APIC.txt>,
          <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
          <http://www.tldp.org/docs.html#howto>.

          If you don't know what to do here, say N.

config X86_X2APIC
        bool "Support x2apic"
        depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
        ---help---
          This enables x2apic support on CPUs that have this feature.

          This allows 32-bit apic IDs (so it can support very large systems),
          and accesses the local apic via MSRs not via mmio.

          If you don't know what to do here, say N.

config SPARSE_IRQ
        bool "Support sparse irq numbering"
        depends on PCI_MSI || HT_IRQ
        ---help---
          This enables support for sparse irqs. This is useful for distro
          kernels that want to define a high CONFIG_NR_CPUS value but still
          want to have low kernel memory footprint on smaller machines.

          ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
            out the irq_desc[] array in a more NUMA-friendly way. )

          If you don't know what to do here, say N.

config NUMA_IRQ_DESC
        def_bool y
        depends on SPARSE_IRQ && NUMA

config X86_MPPARSE
        bool "Enable MPS table" if ACPI
        default y
        depends on X86_LOCAL_APIC
        ---help---
          For old smp systems that do not have proper acpi support. Newer systems
          (esp with 64bit cpus) with acpi support, MADT and DSDT will override it

config X86_BIGSMP
        bool "Support for big SMP systems with more than 8 CPUs"
        depends on X86_32 && SMP
        ---help---
          This option is needed for the systems that have more than 8 CPUs

if X86_32
config X86_EXTENDED_PLATFORM
        bool "Support for extended (non-PC) x86 platforms"
        default y
        ---help---
          If you disable this option then the kernel will only support
          standard PC platforms. (which covers the vast majority of
          systems out there.)

          If you enable this option then you'll be able to select support
          for the following (non-PC) 32 bit x86 platforms:
                AMD Elan
                NUMAQ (IBM/Sequent)
                RDC R-321x SoC
                SGI 320/540 (Visual Workstation)
                Summit/EXA (IBM x440)
                Unisys ES7000 IA32 series
                Moorestown MID devices

          If you have one of these systems, or if you want to build a
          generic distribution kernel, say Y here - otherwise say N.
endif

if X86_64
config X86_EXTENDED_PLATFORM
        bool "Support for extended (non-PC) x86 platforms"
        default y
        ---help---
          If you disable this option then the kernel will only support
          standard PC platforms. (which covers the vast majority of
          systems out there.)

          If you enable this option then you'll be able to select support
          for the following (non-PC) 64 bit x86 platforms:
                ScaleMP vSMP
                SGI Ultraviolet

          If you have one of these systems, or if you want to build a
          generic distribution kernel, say Y here - otherwise say N.
endif
# This is an alphabetically sorted list of 64 bit extended platforms
# Please maintain the alphabetic order if and when there are additions

config X86_VSMP
        bool "ScaleMP vSMP"
        select PARAVIRT
        depends on X86_64 && PCI
        depends on X86_EXTENDED_PLATFORM
        ---help---
          Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
          supposed to run on these EM64T-based machines.  Only choose this option
          if you have one of these machines.

config X86_UV
        bool "SGI Ultraviolet"
        depends on X86_64
        depends on X86_EXTENDED_PLATFORM
        depends on NUMA
        depends on X86_X2APIC
        ---help---
          This option is needed in order to support SGI Ultraviolet systems.
          If you don't have one of these, you should say N here.

# Following is an alphabetically sorted list of 32 bit extended platforms
# Please maintain the alphabetic order if and when there are additions

config X86_ELAN
        bool "AMD Elan"
        depends on X86_32
        depends on X86_EXTENDED_PLATFORM
        ---help---
          Select this for an AMD Elan processor.

          Do not use this option for K6/Athlon/Opteron processors!

          If unsure, choose "PC-compatible" instead.

config X86_MRST
       bool "Moorestown MID platform"
        depends on PCI
        depends on PCI_GOANY
        depends on X86_32
        depends on X86_EXTENDED_PLATFORM
        depends on X86_IO_APIC
        select APB_TIMER
        ---help---
          Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
          Internet Device(MID) platform. Moorestown consists of two chips:
          Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
          Unlike standard x86 PCs, Moorestown does not have many legacy devices
          nor standard legacy replacement devices/features. e.g. Moorestown does
          not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.

config X86_RDC321X
        bool "RDC R-321x SoC"
        depends on X86_32
        depends on X86_EXTENDED_PLATFORM
        select M486
        select X86_REBOOTFIXUPS
        ---help---
          This option is needed for RDC R-321x system-on-chip, also known
          as R-8610-(G).
          If you don't have one of these chips, you should say N here.

config X86_32_NON_STANDARD
        bool "Support non-standard 32-bit SMP architectures"
        depends on X86_32 && SMP
        depends on X86_EXTENDED_PLATFORM
        ---help---
          This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
          subarchitectures.  It is intended for a generic binary kernel.
          if you select them all, kernel will probe it one by one. and will
          fallback to default.

# Alphabetically sorted list of Non standard 32 bit platforms

config X86_NUMAQ
        bool "NUMAQ (IBM/Sequent)"
        depends on X86_32_NON_STANDARD
        depends on PCI
        select NUMA
        select X86_MPPARSE
        ---help---
          This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
          NUMA multiquad box. This changes the way that processors are
          bootstrapped, and uses Clustered Logical APIC addressing mode instead
          of Flat Logical.  You will need a new lynxer.elf file to flash your
          firmware with - send email to <Martin.Bligh@us.ibm.com>.

config X86_SUPPORTS_MEMORY_FAILURE
        def_bool y
        # MCE code calls memory_failure():
        depends on X86_MCE
        # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
        depends on !X86_NUMAQ
        # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
        depends on X86_64 || !SPARSEMEM
        select ARCH_SUPPORTS_MEMORY_FAILURE

config X86_VISWS
        bool "SGI 320/540 (Visual Workstation)"
        depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
        depends on X86_32_NON_STANDARD
        ---help---
          The SGI Visual Workstation series is an IA32-based workstation
          based on SGI systems chips with some legacy PC hardware attached.

          Say Y here to create a kernel to run on the SGI 320 or 540.

          A kernel compiled for the Visual Workstation will run on general
          PCs as well. See <file:Documentation/sgi-visws.txt> for details.

config X86_SUMMIT
        bool "Summit/EXA (IBM x440)"
        depends on X86_32_NON_STANDARD
        ---help---
          This option is needed for IBM systems that use the Summit/EXA chipset.
          In particular, it is needed for the x440.

config X86_ES7000
        bool "Unisys ES7000 IA32 series"
        depends on X86_32_NON_STANDARD && X86_BIGSMP
        ---help---
          Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
          supposed to run on an IA32-based Unisys ES7000 system.

config SCHED_OMIT_FRAME_POINTER
        def_bool y
        prompt "Single-depth WCHAN output"
        depends on X86
        ---help---
          Calculate simpler /proc/<PID>/wchan values. If this option
          is disabled then wchan values will recurse back to the
          caller function. This provides more accurate wchan values,
          at the expense of slightly more scheduling overhead.

          If in doubt, say "Y".

menuconfig PARAVIRT_GUEST
        bool "Paravirtualized guest support"
        ---help---
          Say Y here to get to see options related to running Linux under
          various hypervisors.  This option alone does not add any kernel code.

          If you say N, all options in this submenu will be skipped and disabled.

if PARAVIRT_GUEST

source "arch/x86/xen/Kconfig"

config VMI
        bool "VMI Guest support (DEPRECATED)"
        select PARAVIRT
        depends on X86_32
        ---help---
          VMI provides a paravirtualized interface to the VMware ESX server
          (it could be used by other hypervisors in theory too, but is not
          at the moment), by linking the kernel to a GPL-ed ROM module
          provided by the hypervisor.

          As of September 2009, VMware has started a phased retirement
          of this feature from VMware's products. Please see
          feature-removal-schedule.txt for details.  If you are
          planning to enable this option, please note that you cannot
          live migrate a VMI enabled VM to a future VMware product,
          which doesn't support VMI. So if you expect your kernel to
          seamlessly migrate to newer VMware products, keep this
          disabled.

config KVM_CLOCK
        bool "KVM paravirtualized clock"
        select PARAVIRT
        select PARAVIRT_CLOCK
        ---help---
          Turning on this option will allow you to run a paravirtualized clock
          when running over the KVM hypervisor. Instead of relying on a PIT
          (or probably other) emulation by the underlying device model, the host
          provides the guest with timing infrastructure such as time of day, and
          system time

config KVM_GUEST
        bool "KVM Guest support"
        select PARAVIRT
        ---help---
          This option enables various optimizations for running under the KVM
          hypervisor.

source "arch/x86/lguest/Kconfig"

config PARAVIRT
        bool "Enable paravirtualization code"
        ---help---
          This changes the kernel so it can modify itself when it is run
          under a hypervisor, potentially improving performance significantly
          over full virtualization.  However, when run without a hypervisor
          the kernel is theoretically slower and slightly larger.

config PARAVIRT_SPINLOCKS
        bool "Paravirtualization layer for spinlocks"
        depends on PARAVIRT && SMP && EXPERIMENTAL
        ---help---
          Paravirtualized spinlocks allow a pvops backend to replace the
          spinlock implementation with something virtualization-friendly
          (for example, block the virtual CPU rather than spinning).

          Unfortunately the downside is an up to 5% performance hit on
          native kernels, with various workloads.

          If you are unsure how to answer this question, answer N.

config PARAVIRT_CLOCK
        bool

endif

config PARAVIRT_DEBUG
        bool "paravirt-ops debugging"
        depends on PARAVIRT && DEBUG_KERNEL
        ---help---
          Enable to debug paravirt_ops internals.  Specifically, BUG if
          a paravirt_op is missing when it is called.

config NO_BOOTMEM
        default y
        bool "Disable Bootmem code"
        ---help---
          Use early_res directly instead of bootmem before slab is ready.
                - allocator (buddy) [generic]
                - early allocator (bootmem) [generic]
                - very early allocator (reserve_early*()) [x86]
                - very very early allocator (early brk model) [x86]
          So reduce one layer between early allocator to final allocator


config MEMTEST
        bool "Memtest"
        ---help---
          This option adds a kernel parameter 'memtest', which allows memtest
          to be set.
                memtest=0, mean disabled; -- default
                memtest=1, mean do 1 test pattern;
                ...
                memtest=4, mean do 4 test patterns.
          If you are unsure how to answer this question, answer N.

config X86_SUMMIT_NUMA
        def_bool y
        depends on X86_32 && NUMA && X86_32_NON_STANDARD

config X86_CYCLONE_TIMER
        def_bool y
        depends on X86_32_NON_STANDARD

source "arch/x86/Kconfig.cpu"

config HPET_TIMER
        def_bool X86_64
        prompt "HPET Timer Support" if X86_32
        ---help---
          Use the IA-PC HPET (High Precision Event Timer) to manage
          time in preference to the PIT and RTC, if a HPET is
          present.
          HPET is the next generation timer replacing legacy 8254s.
          The HPET provides a stable time base on SMP
          systems, unlike the TSC, but it is more expensive to access,
          as it is off-chip.  You can find the HPET spec at
          <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.

          You can safely choose Y here.  However, HPET will only be
          activated if the platform and the BIOS support this feature.
          Otherwise the 8254 will be used for timing services.

          Choose N to continue using the legacy 8254 timer.

config HPET_EMULATE_RTC
        def_bool y
        depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)

config APB_TIMER
       def_bool y if MRST
       prompt "Langwell APB Timer Support" if X86_MRST
       help
         APB timer is the replacement for 8254, HPET on X86 MID platforms.
         The APBT provides a stable time base on SMP
         systems, unlike the TSC, but it is more expensive to access,
         as it is off-chip. APB timers are always running regardless of CPU
         C states, they are used as per CPU clockevent device when possible.

# Mark as embedded because too many people got it wrong.
# The code disables itself when not needed.
config DMI
        default y
        bool "Enable DMI scanning" if EMBEDDED
        ---help---
          Enabled scanning of DMI to identify machine quirks. Say Y
          here unless you have verified that your setup is not
          affected by entries in the DMI blacklist. Required by PNP
          BIOS code.

config GART_IOMMU
        bool "GART IOMMU support" if EMBEDDED
        default y
        select SWIOTLB
        depends on X86_64 && PCI && K8_NB
        ---help---
          Support for full DMA access of devices with 32bit memory access only
          on systems with more than 3GB. This is usually needed for USB,
          sound, many IDE/SATA chipsets and some other devices.
          Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
          based hardware IOMMU and a software bounce buffer based IOMMU used
          on Intel systems and as fallback.
          The code is only active when needed (enough memory and limited
          device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
          too.

config CALGARY_IOMMU
        bool "IBM Calgary IOMMU support"
        select SWIOTLB
        depends on X86_64 && PCI && EXPERIMENTAL
        ---help---
          Support for hardware IOMMUs in IBM's xSeries x366 and x460
          systems. Needed to run systems with more than 3GB of memory
          properly with 32-bit PCI devices that do not support DAC
          (Double Address Cycle). Calgary also supports bus level
          isolation, where all DMAs pass through the IOMMU.  This
          prevents them from going anywhere except their intended
          destination. This catches hard-to-find kernel bugs and
          mis-behaving drivers and devices that do not use the DMA-API
          properly to set up their DMA buffers.  The IOMMU can be
          turned off at boot time with the iommu=off parameter.
          Normally the kernel will make the right choice by itself.
          If unsure, say Y.

config CALGARY_IOMMU_ENABLED_BY_DEFAULT
        def_bool y
        prompt "Should Calgary be enabled by default?"
        depends on CALGARY_IOMMU
        ---help---
          Should Calgary be enabled by default? if you choose 'y', Calgary
          will be used (if it exists). If you choose 'n', Calgary will not be
          used even if it exists. If you choose 'n' and would like to use
          Calgary anyway, pass 'iommu=calgary' on the kernel command line.
          If unsure, say Y.

config AMD_IOMMU
        bool "AMD IOMMU support"
        select SWIOTLB
        select PCI_MSI
        depends on X86_64 && PCI && ACPI
        ---help---
          With this option you can enable support for AMD IOMMU hardware in
          your system. An IOMMU is a hardware component which provides
          remapping of DMA memory accesses from devices. With an AMD IOMMU you
          can isolate the the DMA memory of different devices and protect the
          system from misbehaving device drivers or hardware.

          You can find out if your system has an AMD IOMMU if you look into
          your BIOS for an option to enable it or if you have an IVRS ACPI
          table.

config AMD_IOMMU_STATS
        bool "Export AMD IOMMU statistics to debugfs"
        depends on AMD_IOMMU
        select DEBUG_FS
        ---help---
          This option enables code in the AMD IOMMU driver to collect various
          statistics about whats happening in the driver and exports that
          information to userspace via debugfs.
          If unsure, say N.

# need this always selected by IOMMU for the VIA workaround
config SWIOTLB
        def_bool y if X86_64
        ---help---
          Support for software bounce buffers used on x86-64 systems
          which don't have a hardware IOMMU (e.g. the current generation
          of Intel's x86-64 CPUs). Using this PCI devices which can only
          access 32-bits of memory can be used on systems with more than
          3 GB of memory. If unsure, say Y.

config IOMMU_HELPER
        def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)

config IOMMU_API
        def_bool (AMD_IOMMU || DMAR)

config MAXSMP
        bool "Enable Maximum number of SMP Processors and NUMA Nodes"
        depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
        select CPUMASK_OFFSTACK
        ---help---
          Enable maximum number of CPUS and NUMA Nodes for this architecture.
          If unsure, say N.

config NR_CPUS
        int "Maximum number of CPUs" if SMP && !MAXSMP
        range 2 8 if SMP && X86_32 && !X86_BIGSMP
        range 2 512 if SMP && !MAXSMP
        default "1" if !SMP
        default "4096" if MAXSMP
        default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
        default "8" if SMP
        ---help---
          This allows you to specify the maximum number of CPUs which this
          kernel will support.  The maximum supported value is 512 and the
          minimum value which makes sense is 2.

          This is purely to save memory - each supported CPU adds
          approximately eight kilobytes to the kernel image.

config SCHED_SMT
        bool "SMT (Hyperthreading) scheduler support"
        depends on X86_HT
        ---help---
          SMT scheduler support improves the CPU scheduler's decision making
          when dealing with Intel Pentium 4 chips with HyperThreading at a
          cost of slightly increased overhead in some places. If unsure say
          N here.

config SCHED_MC
        def_bool y
        prompt "Multi-core scheduler support"
        depends on X86_HT
        ---help---
          Multi-core scheduler support improves the CPU scheduler's decision
          making when dealing with multi-core CPU chips at a cost of slightly
          increased overhead in some places. If unsure say N here.

config IRQ_TIME_ACCOUNTING
        bool "Fine granularity task level IRQ time accounting"
        default n
        ---help---
          Select this option to enable fine granularity task irq time
          accounting. This is done by reading a timestamp on each
          transitions between softirq and hardirq state, so there can be a
          small performance impact.

          If in doubt, say N here.

source "kernel/Kconfig.preempt"

config X86_UP_APIC
        bool "Local APIC support on uniprocessors"
        depends on X86_32 && !SMP && !X86_32_NON_STANDARD
        ---help---
          A local APIC (Advanced Programmable Interrupt Controller) is an
          integrated interrupt controller in the CPU. If you have a single-CPU
          system which has a processor with a local APIC, you can say Y here to
          enable and use it. If you say Y here even though your machine doesn't
          have a local APIC, then the kernel will still run with no slowdown at
          all. The local APIC supports CPU-generated self-interrupts (timer,
          performance counters), and the NMI watchdog which detects hard
          lockups.

config X86_UP_IOAPIC
        bool "IO-APIC support on uniprocessors"
        depends on X86_UP_APIC
        ---help---
          An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
          SMP-capable replacement for PC-style interrupt controllers. Most
          SMP systems and many recent uniprocessor systems have one.

          If you have a single-CPU system with an IO-APIC, you can say Y here
          to use it. If you say Y here even though your machine doesn't have
          an IO-APIC, then the kernel will still run with no slowdown at all.

config X86_LOCAL_APIC
        def_bool y
        depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC

config X86_IO_APIC
        def_bool y
        depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC

config X86_VISWS_APIC
        def_bool y
        depends on X86_32 && X86_VISWS

config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
        bool "Reroute for broken boot IRQs"
        depends on X86_IO_APIC
        ---help---
          This option enables a workaround that fixes a source of
          spurious interrupts. This is recommended when threaded
          interrupt handling is used on systems where the generation of
          superfluous "boot interrupts" cannot be disabled.

          Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
          entry in the chipset's IO-APIC is masked (as, e.g. the RT
          kernel does during interrupt handling). On chipsets where this
          boot IRQ generation cannot be disabled, this workaround keeps
          the original IRQ line masked so that only the equivalent "boot
          IRQ" is delivered to the CPUs. The workaround also tells the
          kernel to set up the IRQ handler on the boot IRQ line. In this
          way only one interrupt is delivered to the kernel. Otherwise
          the spurious second interrupt may cause the kernel to bring
          down (vital) interrupt lines.

          Only affects "broken" chipsets. Interrupt sharing may be
          increased on these systems.

config X86_MCE
        bool "Machine Check / overheating reporting"
        ---help---
          Machine Check support allows the processor to notify the
          kernel if it detects a problem (e.g. overheating, data corruption).
          The action the kernel takes depends on the severity of the problem,
          ranging from warning messages to halting the machine.

config X86_MCE_INTEL
        def_bool y
        prompt "Intel MCE features"
        depends on X86_MCE && X86_LOCAL_APIC
        ---help---
           Additional support for intel specific MCE features such as
           the thermal monitor.

config X86_MCE_AMD
        def_bool y
        prompt "AMD MCE features"
        depends on X86_MCE && X86_LOCAL_APIC
        ---help---
           Additional support for AMD specific MCE features such as
           the DRAM Error Threshold.

config X86_ANCIENT_MCE
        bool "Support for old Pentium 5 / WinChip machine checks"
        depends on X86_32 && X86_MCE
        ---help---
          Include support for machine check handling on old Pentium 5 or WinChip
          systems. These typically need to be enabled explicitely on the command
          line.

config X86_MCE_THRESHOLD
        depends on X86_MCE_AMD || X86_MCE_INTEL
        def_bool y

config X86_MCE_INJECT
        depends on X86_MCE
        tristate "Machine check injector support"
        ---help---
          Provide support for injecting machine checks for testing purposes.
          If you don't know what a machine check is and you don't do kernel
          QA it is safe to say n.

config X86_THERMAL_VECTOR
        def_bool y
        depends on X86_MCE_INTEL

config VM86
        bool "Enable VM86 support" if EMBEDDED
        default y
        depends on X86_32
        ---help---
          This option is required by programs like DOSEMU to run 16-bit legacy
          code on X86 processors. It also may be needed by software like
          XFree86 to initialize some video cards via BIOS. Disabling this
          option saves about 6k.

config TOSHIBA
        tristate "Toshiba Laptop support"
        depends on X86_32
        ---help---
          This adds a driver to safely access the System Management Mode of
          the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
          not work on models with a Phoenix BIOS. The System Management Mode
          is used to set the BIOS and power saving options on Toshiba portables.

          For information on utilities to make use of this driver see the
          Toshiba Linux utilities web site at:
          <http://www.buzzard.org.uk/toshiba/>.

          Say Y if you intend to run this kernel on a Toshiba portable.
          Say N otherwise.

config I8K
        tristate "Dell laptop support"
        ---help---
          This adds a driver to safely access the System Management Mode
          of the CPU on the Dell Inspiron 8000. The System Management Mode
          is used to read cpu temperature and cooling fan status and to
          control the fans on the I8K portables.

          This driver has been tested only on the Inspiron 8000 but it may
          also work with other Dell laptops. You can force loading on other
          models by passing the parameter `force=1' to the module. Use at
          your own risk.

          For information on utilities to make use of this driver see the
          I8K Linux utilities web site at:
          <http://people.debian.org/~dz/i8k/>

          Say Y if you intend to run this kernel on a Dell Inspiron 8000.
          Say N otherwise.

config X86_REBOOTFIXUPS
        bool "Enable X86 board specific fixups for reboot"
        depends on X86_32
        ---help---
          This enables chipset and/or board specific fixups to be done
          in order to get reboot to work correctly. This is only needed on
          some combinations of hardware and BIOS. The symptom, for which
          this config is intended, is when reboot ends with a stalled/hung
          system.

          Currently, the only fixup is for the Geode machines using
          CS5530A and CS5536 chipsets and the RDC R-321x SoC.

          Say Y if you want to enable the fixup. Currently, it's safe to
          enable this option even if you don't need it.
          Say N otherwise.

config MICROCODE
        tristate "/dev/cpu/microcode - microcode support"
        select FW_LOADER
        ---help---
          If you say Y here, you will be able to update the microcode on
          certain Intel and AMD processors. The Intel support is for the
          IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
          Pentium 4, Xeon etc. The AMD support is for family 0x10 and
          0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
          You will obviously need the actual microcode binary data itself
          which is not shipped with the Linux kernel.

          This option selects the general module only, you need to select
          at least one vendor specific module as well.

          To compile this driver as a module, choose M here: the
          module will be called microcode.

config MICROCODE_INTEL
        bool "Intel microcode patch loading support"
        depends on MICROCODE
        default MICROCODE
        select FW_LOADER
        ---help---
          This options enables microcode patch loading support for Intel
          processors.

          For latest news and information on obtaining all the required
          Intel ingredients for this driver, check:
          <http://www.urbanmyth.org/microcode/>.

config MICROCODE_AMD
        bool "AMD microcode patch loading support"
        depends on MICROCODE
        select FW_LOADER
        ---help---
          If you select this option, microcode patch loading support for AMD
          processors will be enabled.

config MICROCODE_OLD_INTERFACE
        def_bool y
        depends on MICROCODE

config X86_MSR
        tristate "/dev/cpu/*/msr - Model-specific register support"
        ---help---
          This device gives privileged processes access to the x86
          Model-Specific Registers (MSRs).  It is a character device with
          major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
          MSR accesses are directed to a specific CPU on multi-processor
          systems.

config X86_CPUID
        tristate "/dev/cpu/*/cpuid - CPU information support"
        ---help---
          This device gives processes access to the x86 CPUID instruction to
          be executed on a specific processor.  It is a character device
          with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
          /dev/cpu/31/cpuid.

choice
        prompt "High Memory Support"
        default HIGHMEM64G if X86_NUMAQ
        default HIGHMEM4G
        depends on X86_32

config NOHIGHMEM
        bool "off"
        depends on !X86_NUMAQ
        ---help---
          Linux can use up to 64 Gigabytes of physical memory on x86 systems.
          However, the address space of 32-bit x86 processors is only 4
          Gigabytes large. That means that, if you have a large amount of
          physical memory, not all of it can be "permanently mapped" by the
          kernel. The physical memory that's not permanently mapped is called
          "high memory".

          If you are compiling a kernel which will never run on a machine with
          more than 1 Gigabyte total physical RAM, answer "off" here (default
          choice and suitable for most users). This will result in a "3GB/1GB"
          split: 3GB are mapped so that each process sees a 3GB virtual memory
          space and the remaining part of the 4GB virtual memory space is used
          by the kernel to permanently map as much physical memory as
          possible.

          If the machine has between 1 and 4 Gigabytes physical RAM, then
          answer "4GB" here.

          If more than 4 Gigabytes is used then answer "64GB" here. This
          selection turns Intel PAE (Physical Address Extension) mode on.
          PAE implements 3-level paging on IA32 processors. PAE is fully
          supported by Linux, PAE mode is implemented on all recent Intel
          processors (Pentium Pro and better). NOTE: If you say "64GB" here,
          then the kernel will not boot on CPUs that don't support PAE!

          The actual amount of total physical memory will either be
          auto detected or can be forced by using a kernel command line option
          such as "mem=256M". (Try "man bootparam" or see the documentation of
          your boot loader (lilo or loadlin) about how to pass options to the
          kernel at boot time.)

          If unsure, say "off".

config HIGHMEM4G
        bool "4GB"
        depends on !X86_NUMAQ
        ---help---
          Select this if you have a 32-bit processor and between 1 and 4
          gigabytes of physical RAM.

config HIGHMEM64G
        bool "64GB"
        depends on !M386 && !M486
        select X86_PAE
        ---help---
          Select this if you have a 32-bit processor and more than 4
          gigabytes of physical RAM.

endchoice

choice
        depends on EXPERIMENTAL
        prompt "Memory split" if EMBEDDED
        default VMSPLIT_3G
        depends on X86_32
        ---help---
          Select the desired split between kernel and user memory.

          If the address range available to the kernel is less than the
          physical memory installed, the remaining memory will be available
          as "high memory". Accessing high memory is a little more costly
          than low memory, as it needs to be mapped into the kernel first.
          Note that increasing the kernel address space limits the range
          available to user programs, making the address space there
          tighter.  Selecting anything other than the default 3G/1G split
          will also likely make your kernel incompatible with binary-only
          kernel modules.

          If you are not absolutely sure what you are doing, leave this
          option alone!

        config VMSPLIT_3G
                bool "3G/1G user/kernel split"
        config VMSPLIT_3G_OPT
                depends on !X86_PAE
                bool "3G/1G user/kernel split (for full 1G low memory)"
        config VMSPLIT_2G
                bool "2G/2G user/kernel split"
        config VMSPLIT_2G_OPT
                depends on !X86_PAE
                bool "2G/2G user/kernel split (for full 2G low memory)"
        config VMSPLIT_1G
                bool "1G/3G user/kernel split"
endchoice

config PAGE_OFFSET
        hex
        default 0xB0000000 if VMSPLIT_3G_OPT
        default 0x80000000 if VMSPLIT_2G
        default 0x78000000 if VMSPLIT_2G_OPT
        default 0x40000000 if VMSPLIT_1G
        default 0xC0000000
        depends on X86_32

config HIGHMEM
        def_bool y
        depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)

config X86_PAE
        bool "PAE (Physical Address Extension) Support"
        depends on X86_32 && !HIGHMEM4G
        ---help---
          PAE is required for NX support, and furthermore enables
          larger swapspace support for non-overcommit purposes. It
          has the cost of more pagetable lookup overhead, and also
          consumes more pagetable space per process.

config ARCH_PHYS_ADDR_T_64BIT
        def_bool X86_64 || X86_PAE

config DIRECT_GBPAGES
        bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
        default y
        depends on X86_64
        ---help---
          Allow the kernel linear mapping to use 1GB pages on CPUs that
          support it. This can improve the kernel's performance a tiny bit by
          reducing TLB pressure. If in doubt, say "Y".

# Common NUMA Features
config NUMA
        bool "Numa Memory Allocation and Scheduler Support"
        depends on SMP
        depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
        default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
        ---help---
          Enable NUMA (Non Uniform Memory Access) support.

          The kernel will try to allocate memory used by a CPU on the
          local memory controller of the CPU and add some more
          NUMA awareness to the kernel.

          For 64-bit this is recommended if the system is Intel Core i7
          (or later), AMD Opteron, or EM64T NUMA.

          For 32-bit this is only needed on (rare) 32-bit-only platforms
          that support NUMA topologies, such as NUMAQ / Summit, or if you
          boot a 32-bit kernel on a 64-bit NUMA platform.

          Otherwise, you should say N.

comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
        depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)

config K8_NUMA
        def_bool y
        prompt "Old style AMD Opteron NUMA detection"
        depends on X86_64 && NUMA && PCI
        ---help---
          Enable K8 NUMA node topology detection.  You should say Y here if
          you have a multi processor AMD K8 system. This uses an old
          method to read the NUMA configuration directly from the builtin
          Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
          instead, which also takes priority if both are compiled in.

config X86_64_ACPI_NUMA
        def_bool y
        prompt "ACPI NUMA detection"
        depends on X86_64 && NUMA && ACPI && PCI
        select ACPI_NUMA
        ---help---
          Enable ACPI SRAT based node topology detection.

# Some NUMA nodes have memory ranges that span
# other nodes.  Even though a pfn is valid and
# between a node's start and end pfns, it may not
# reside on that node.  See memmap_init_zone()
# for details.
config NODES_SPAN_OTHER_NODES
        def_bool y
        depends on X86_64_ACPI_NUMA

config NUMA_EMU
        bool "NUMA emulation"
        depends on X86_64 && NUMA
        ---help---
          Enable NUMA emulation. A flat machine will be split
          into virtual nodes when booted with "numa=fake=N", where N is the
          number of nodes. This is only useful for debugging.

config NODES_SHIFT
        int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
        range 1 10
        default "10" if MAXSMP
        default "6" if X86_64
        default "4" if X86_NUMAQ
        default "3"
        depends on NEED_MULTIPLE_NODES
        ---help---
          Specify the maximum number of NUMA Nodes available on the target
          system.  Increases memory reserved to accommodate various tables.

config HAVE_ARCH_BOOTMEM
        def_bool y
        depends on X86_32 && NUMA

config ARCH_HAVE_MEMORY_PRESENT
        def_bool y
        depends on X86_32 && DISCONTIGMEM

config NEED_NODE_MEMMAP_SIZE
        def_bool y
        depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)

config HAVE_ARCH_ALLOC_REMAP
        def_bool y
        depends on X86_32 && NUMA

config ARCH_FLATMEM_ENABLE
        def_bool y
        depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA

config ARCH_DISCONTIGMEM_ENABLE
        def_bool y
        depends on NUMA && X86_32

config ARCH_DISCONTIGMEM_DEFAULT
        def_bool y
        depends on NUMA && X86_32

config ARCH_PROC_KCORE_TEXT
        def_bool y
        depends on X86_64 && PROC_KCORE

config ARCH_SPARSEMEM_DEFAULT
        def_bool y
        depends on X86_64

config ARCH_SPARSEMEM_ENABLE
        def_bool y
        depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
        select SPARSEMEM_STATIC if X86_32
        select SPARSEMEM_VMEMMAP_ENABLE if X86_64

config ARCH_SELECT_MEMORY_MODEL
        def_bool y
        depends on ARCH_SPARSEMEM_ENABLE

config ARCH_MEMORY_PROBE
        def_bool X86_64
        depends on MEMORY_HOTPLUG

config ILLEGAL_POINTER_VALUE
       hex
       default 0 if X86_32
       default 0xdead000000000000 if X86_64

source "mm/Kconfig"

config HIGHPTE
        bool "Allocate 3rd-level pagetables from highmem"
        depends on HIGHMEM
        ---help---
          The VM uses one page table entry for each page of physical memory.
          For systems with a lot of RAM, this can be wasteful of precious
          low memory.  Setting this option will put user-space page table
          entries in high memory.

config X86_CHECK_BIOS_CORRUPTION
        bool "Check for low memory corruption"
        ---help---
          Periodically check for memory corruption in low memory, which
          is suspected to be caused by BIOS.  Even when enabled in the
          configuration, it is disabled at runtime.  Enable it by
          setting "memory_corruption_check=1" on the kernel command
          line.  By default it scans the low 64k of memory every 60
          seconds; see the memory_corruption_check_size and
          memory_corruption_check_period parameters in
          Documentation/kernel-parameters.txt to adjust this.

          When enabled with the default parameters, this option has
          almost no overhead, as it reserves a relatively small amount
          of memory and scans it infrequently.  It both detects corruption
          and prevents it from affecting the running system.

          It is, however, intended as a diagnostic tool; if repeatable
          BIOS-originated corruption always affects the same memory,
          you can use memmap= to prevent the kernel from using that
          memory.

config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
        bool "Set the default setting of memory_corruption_check"
        depends on X86_CHECK_BIOS_CORRUPTION
        default y
        ---help---
          Set whether the default state of memory_corruption_check is
          on or off.

config X86_RESERVE_LOW_64K
        bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
        default y
        ---help---
          Reserve the first 64K of physical RAM on BIOSes that are known
          to potentially corrupt that memory range. A numbers of BIOSes are
          known to utilize this area during suspend/resume, so it must not
          be used by the kernel.

          Set this to N if you are absolutely sure that you trust the BIOS
          to get all its memory reservations and usages right.

          If you have doubts about the BIOS (e.g. suspend/resume does not
          work or there's kernel crashes after certain hardware hotplug
          events) and it's not AMI or Phoenix, then you might want to enable
          X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
          corruption patterns.

          Say Y if unsure.

config MATH_EMULATION
        bool
        prompt "Math emulation" if X86_32
        ---help---
          Linux can emulate a math coprocessor (used for floating point
          operations) if you don't have one. 486DX and Pentium processors have
          a math coprocessor built in, 486SX and 386 do not, unless you added
          a 487DX or 387, respectively. (The messages during boot time can
          give you some hints here ["man dmesg"].) Everyone needs either a
          coprocessor or this emulation.

          If you don't have a math coprocessor, you need to say Y here; if you
          say Y here even though you have a coprocessor, the coprocessor will
          be used nevertheless. (This behavior can be changed with the kernel
          command line option "no387", which comes handy if your coprocessor
          is broken. Try "man bootparam" or see the documentation of your boot
          loader (lilo or loadlin) about how to pass options to the kernel at
          boot time.) This means that it is a good idea to say Y here if you
          intend to use this kernel on different machines.

          More information about the internals of the Linux math coprocessor
          emulation can be found in <file:arch/x86/math-emu/README>.

          If you are not sure, say Y; apart from resulting in a 66 KB bigger
          kernel, it won't hurt.

config MTRR
        def_bool y
        prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
        ---help---
          On Intel P6 family processors (Pentium Pro, Pentium II and later)
          the Memory Type Range Registers (MTRRs) may be used to control
          processor access to memory ranges. This is most useful if you have
          a video (VGA) card on a PCI or AGP bus. Enabling write-combining
          allows bus write transfers to be combined into a larger transfer
          before bursting over the PCI/AGP bus. This can increase performance
          of image write operations 2.5 times or more. Saying Y here creates a
          /proc/mtrr file which may be used to manipulate your processor's
          MTRRs. Typically the X server should use this.

          This code has a reasonably generic interface so that similar
          control registers on other processors can be easily supported
          as well:

          The Cyrix 6x86, 6x86MX and M II processors have Address Range
          Registers (ARRs) which provide a similar functionality to MTRRs. For
          these, the ARRs are used to emulate the MTRRs.
          The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
          MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
          write-combining. All of these processors are supported by this code
          and it makes sense to say Y here if you have one of them.

          Saying Y here also fixes a problem with buggy SMP BIOSes which only
          set the MTRRs for the boot CPU and not for the secondary CPUs. This
          can lead to all sorts of problems, so it's good to say Y here.

          You can safely say Y even if your machine doesn't have MTRRs, you'll
          just add about 9 KB to your kernel.

          See <file:Documentation/x86/mtrr.txt> for more information.

config MTRR_SANITIZER
        def_bool y
        prompt "MTRR cleanup support"
        depends on MTRR
        ---help---
          Convert MTRR layout from continuous to discrete, so X drivers can
          add writeback entries.

          Can be disabled with disable_mtrr_cleanup on the kernel command line.
          The largest mtrr entry size for a continuous block can be set with
          mtrr_chunk_size.

          If unsure, say Y.

config MTRR_SANITIZER_ENABLE_DEFAULT
        int "MTRR cleanup enable value (0-1)"
        range 0 1
        default "0"
        depends on MTRR_SANITIZER
        ---help---
          Enable mtrr cleanup default value

config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
        int "MTRR cleanup spare reg num (0-7)"
        range 0 7
        default "1"
        depends on MTRR_SANITIZER
        ---help---
          mtrr cleanup spare entries default, it can be changed via
          mtrr_spare_reg_nr=N on the kernel command line.

config X86_PAT
        def_bool y
        prompt "x86 PAT support" if EMBEDDED
        depends on MTRR
        ---help---
          Use PAT attributes to setup page level cache control.

          PATs are the modern equivalents of MTRRs and are much more
          flexible than MTRRs.

          Say N here if you see bootup problems (boot crash, boot hang,
          spontaneous reboots) or a non-working video driver.

          If unsure, say Y.

config ARCH_USES_PG_UNCACHED
        def_bool y
        depends on X86_PAT

config EFI
        bool "EFI runtime service support"
        depends on ACPI
        ---help---
          This enables the kernel to use EFI runtime services that are
          available (such as the EFI variable services).

          This option is only useful on systems that have EFI firmware.
          In addition, you should use the latest ELILO loader available
          at <http://elilo.sourceforge.net> in order to take advantage
          of EFI runtime services. However, even with this option, the
          resultant kernel should continue to boot on existing non-EFI
          platforms.

config SECCOMP
        def_bool y
        prompt "Enable seccomp to safely compute untrusted bytecode"
        ---help---
          This kernel feature is useful for number crunching applications
          that may need to compute untrusted bytecode during their
          execution. By using pipes or other transports made available to
          the process as file descriptors supporting the read/write
          syscalls, it's possible to isolate those applications in
          their own address space using seccomp. Once seccomp is
          enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
          and the task is only allowed to execute a few safe syscalls
          defined by each seccomp mode.

          If unsure, say Y. Only embedded should say N here.

config CC_STACKPROTECTOR
        bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
        ---help---
          This option turns on the -fstack-protector GCC feature. This
          feature puts, at the beginning of functions, a canary value on
          the stack just before the return address, and validates
          the value just before actually returning.  Stack based buffer
          overflows (that need to overwrite this return address) now also
          overwrite the canary, which gets detected and the attack is then
          neutralized via a kernel panic.

          This feature requires gcc version 4.2 or above, or a distribution
          gcc with the feature backported. Older versions are automatically
          detected and for those versions, this configuration option is
          ignored. (and a warning is printed during bootup)

source kernel/Kconfig.hz

config KEXEC
        bool "kexec system call"
        ---help---
          kexec is a system call that implements the ability to shutdown your
          current kernel, and to start another kernel.  It is like a reboot
          but it is independent of the system firmware.   And like a reboot
          you can start any kernel with it, not just Linux.

          The name comes from the similarity to the exec system call.

          It is an ongoing process to be certain the hardware in a machine
          is properly shutdown, so do not be surprised if this code does not
          initially work for you.  It may help to enable device hotplugging
          support.  As of this writing the exact hardware interface is
          strongly in flux, so no good recommendation can be made.

config CRASH_DUMP
        bool "kernel crash dumps"
        depends on X86_64 || (X86_32 && HIGHMEM)
        ---help---
          Generate crash dump after being started by kexec.
          This should be normally only set in special crash dump kernels
          which are loaded in the main kernel with kexec-tools into
          a specially reserved region and then later executed after
          a crash by kdump/kexec. The crash dump kernel must be compiled
          to a memory address not used by the main kernel or BIOS using
          PHYSICAL_START, or it must be built as a relocatable image
          (CONFIG_RELOCATABLE=y).
          For more details see Documentation/kdump/kdump.txt

config KEXEC_JUMP
        bool "kexec jump (EXPERIMENTAL)"
        depends on EXPERIMENTAL
        depends on KEXEC && HIBERNATION
        ---help---
          Jump between original kernel and kexeced kernel and invoke
          code in physical address mode via KEXEC

config PHYSICAL_START
        hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
        default "0x1000000"
        ---help---
          This gives the physical address where the kernel is loaded.

          If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
          bzImage will decompress itself to above physical address and
          run from there. Otherwise, bzImage will run from the address where
          it has been loaded by the boot loader and will ignore above physical
          address.

          In normal kdump cases one does not have to set/change this option
          as now bzImage can be compiled as a completely relocatable image
          (CONFIG_RELOCATABLE=y) and be used to load and run from a different
          address. This option is mainly useful for the folks who don't want
          to use a bzImage for capturing the crash dump and want to use a
          vmlinux instead. vmlinux is not relocatable hence a kernel needs
          to be specifically compiled to run from a specific memory area
          (normally a reserved region) and this option comes handy.

          So if you are using bzImage for capturing the crash dump,
          leave the value here unchanged to 0x1000000 and set
          CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
          for capturing the crash dump change this value to start of
          the reserved region.  In other words, it can be set based on
          the "X" value as specified in the "crashkernel=YM@XM"
          command line boot parameter passed to the panic-ed
          kernel. Please take a look at Documentation/kdump/kdump.txt
          for more details about crash dumps.

          Usage of bzImage for capturing the crash dump is recommended as
          one does not have to build two kernels. Same kernel can be used
          as production kernel and capture kernel. Above option should have
          gone away after relocatable bzImage support is introduced. But it
          is present because there are users out there who continue to use
          vmlinux for dump capture. This option should go away down the
          line.

          Don't change this unless you know what you are doing.

config RELOCATABLE
        bool "Build a relocatable kernel"
        default y
        ---help---
          This builds a kernel image that retains relocation information
          so it can be loaded someplace besides the default 1MB.
          The relocations tend to make the kernel binary about 10% larger,
          but are discarded at runtime.

          One use is for the kexec on panic case where the recovery kernel
          must live at a different physical address than the primary
          kernel.

          Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
          it has been loaded at and the compile time physical address
          (CONFIG_PHYSICAL_START) is ignored.

# Relocation on x86-32 needs some additional build support
config X86_NEED_RELOCS
        def_bool y
        depends on X86_32 && RELOCATABLE

config PHYSICAL_ALIGN
        hex "Alignment value to which kernel should be aligned" if X86_32
        default "0x1000000"
        range 0x2000 0x1000000
        ---help---
          This value puts the alignment restrictions on physical address
          where kernel is loaded and run from. Kernel is compiled for an
          address which meets above alignment restriction.

          If bootloader loads the kernel at a non-aligned address and
          CONFIG_RELOCATABLE is set, kernel will move itself to nearest
          address aligned to above value and run from there.

          If bootloader loads the kernel at a non-aligned address and
          CONFIG_RELOCATABLE is not set, kernel will ignore the run time
          load address and decompress itself to the address it has been
          compiled for and run from there. The address for which kernel is
          compiled already meets above alignment restrictions. Hence the
          end result is that kernel runs from a physical address meeting
          above alignment restrictions.

          Don't change this unless you know what you are doing.

config HOTPLUG_CPU
        bool "Support for hot-pluggable CPUs"
        depends on SMP && HOTPLUG
        ---help---
          Say Y here to allow turning CPUs off and on. CPUs can be
          controlled through /sys/devices/system/cpu.
          ( Note: power management support will enable this option
            automatically on SMP systems. )
          Say N if you want to disable CPU hotplug.

config COMPAT_VDSO
        def_bool y
        prompt "Compat VDSO support"
        depends on X86_32 || IA32_EMULATION
        ---help---
          Map the 32-bit VDSO to the predictable old-style address too.

          Say N here if you are running a sufficiently recent glibc
          version (2.3.3 or later), to remove the high-mapped
          VDSO mapping and to exclusively use the randomized VDSO.

          If unsure, say Y.

config CMDLINE_BOOL
        bool "Built-in kernel command line"
        ---help---
          Allow for specifying boot arguments to the kernel at
          build time.  On some systems (e.g. embedded ones), it is
          necessary or convenient to provide some or all of the
          kernel boot arguments with the kernel itself (that is,
          to not rely on the boot loader to provide them.)

          To compile command line arguments into the kernel,
          set this option to 'Y', then fill in the
          the boot arguments in CONFIG_CMDLINE.

          Systems with fully functional boot loaders (i.e. non-embedded)
          should leave this option set to 'N'.

config CMDLINE
        string "Built-in kernel command string"
        depends on CMDLINE_BOOL
        default ""
        ---help---
          Enter arguments here that should be compiled into the kernel
          image and used at boot time.  If the boot loader provides a
          command line at boot time, it is appended to this string to
          form the full kernel command line, when the system boots.

          However, you can use the CONFIG_CMDLINE_OVERRIDE option to
          change this behavior.

          In most cases, the command line (whether built-in or provided
          by the boot loader) should specify the device for the root
          file system.

config CMDLINE_OVERRIDE
        bool "Built-in command line overrides boot loader arguments"
        depends on CMDLINE_BOOL
        ---help---
          Set this option to 'Y' to have the kernel ignore the boot loader
          command line, and use ONLY the built-in command line.

          This is used to work around broken boot loaders.  This should
          be set to 'N' under normal conditions.

endmenu

config ARCH_ENABLE_MEMORY_HOTPLUG
        def_bool y
        depends on X86_64 || (X86_32 && HIGHMEM)

config ARCH_ENABLE_MEMORY_HOTREMOVE
        def_bool y
        depends on MEMORY_HOTPLUG

config HAVE_ARCH_EARLY_PFN_TO_NID
        def_bool X86_64
        depends on NUMA

config USE_PERCPU_NUMA_NODE_ID
        def_bool X86_64
        depends on NUMA

menu "Power management and ACPI options"

config ARCH_HIBERNATION_HEADER
        def_bool y
        depends on X86_64 && HIBERNATION

source "kernel/power/Kconfig"

source "drivers/acpi/Kconfig"

source "drivers/sfi/Kconfig"

config X86_APM_BOOT
        def_bool y
        depends on APM || APM_MODULE

menuconfig APM
        tristate "APM (Advanced Power Management) BIOS support"
        depends on X86_32 && PM_SLEEP
        ---help---
          APM is a BIOS specification for saving power using several different
          techniques. This is mostly useful for battery powered laptops with
          APM compliant BIOSes. If you say Y here, the system time will be
          reset after a RESUME operation, the /proc/apm device will provide
          battery status information, and user-space programs will receive
          notification of APM "events" (e.g. battery status change).

          If you select "Y" here, you can disable actual use of the APM
          BIOS by passing the "apm=off" option to the kernel at boot time.

          Note that the APM support is almost completely disabled for
          machines with more than one CPU.

          In order to use APM, you will need supporting software. For location
          and more information, read <file:Documentation/power/pm.txt> and the
          Battery Powered Linux mini-HOWTO, available from
          <http://www.tldp.org/docs.html#howto>.

          This driver does not spin down disk drives (see the hdparm(8)
          manpage ("man 8 hdparm") for that), and it doesn't turn off
          VESA-compliant "green" monitors.

          This driver does not support the TI 4000M TravelMate and the ACER
          486/DX4/75 because they don't have compliant BIOSes. Many "green"
          desktop machines also don't have compliant BIOSes, and this driver
          may cause those machines to panic during the boot phase.

          Generally, if you don't have a battery in your machine, there isn't
          much point in using this driver and you should say N. If you get
          random kernel OOPSes or reboots that don't seem to be related to
          anything, try disabling/enabling this option (or disabling/enabling
          APM in your BIOS).

          Some other things you should try when experiencing seemingly random,
          "weird" problems:

          1) make sure that you have enough swap space and that it is
          enabled.
          2) pass the "no-hlt" option to the kernel
          3) switch on floating point emulation in the kernel and pass
          the "no387" option to the kernel
          4) pass the "floppy=nodma" option to the kernel
          5) pass the "mem=4M" option to the kernel (thereby disabling
          all but the first 4 MB of RAM)
          6) make sure that the CPU is not over clocked.
          7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
          8) disable the cache from your BIOS settings
          9) install a fan for the video card or exchange video RAM
          10) install a better fan for the CPU
          11) exchange RAM chips
          12) exchange the motherboard.

          To compile this driver as a module, choose M here: the
          module will be called apm.

if APM

config APM_IGNORE_USER_SUSPEND
        bool "Ignore USER SUSPEND"
        ---help---
          This option will ignore USER SUSPEND requests. On machines with a
          compliant APM BIOS, you want to say N. However, on the NEC Versa M
          series notebooks, it is necessary to say Y because of a BIOS bug.

config APM_DO_ENABLE
        bool "Enable PM at boot time"
        ---help---
          Enable APM features at boot time. From page 36 of the APM BIOS
          specification: "When disabled, the APM BIOS does not automatically
          power manage devices, enter the Standby State, enter the Suspend
          State, or take power saving steps in response to CPU Idle calls."
          This driver will make CPU Idle calls when Linux is idle (unless this
          feature is turned off -- see "Do CPU IDLE calls", below). This
          should always save battery power, but more complicated APM features
          will be dependent on your BIOS implementation. You may need to turn
          this option off if your computer hangs at boot time when using APM
          support, or if it beeps continuously instead of suspending. Turn
          this off if you have a NEC UltraLite Versa 33/C or a Toshiba
          T400CDT. This is off by default since most machines do fine without
          this feature.

config APM_CPU_IDLE
        bool "Make CPU Idle calls when idle"
        ---help---
          Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
          On some machines, this can activate improved power savings, such as
          a slowed CPU clock rate, when the machine is idle. These idle calls
          are made after the idle loop has run for some length of time (e.g.,
          333 mS). On some machines, this will cause a hang at boot time or
          whenever the CPU becomes idle. (On machines with more than one CPU,
          this option does nothing.)

config APM_DISPLAY_BLANK
        bool "Enable console blanking using APM"
        ---help---
          Enable console blanking using the APM. Some laptops can use this to
          turn off the LCD backlight when the screen blanker of the Linux
          virtual console blanks the screen. Note that this is only used by
          the virtual console screen blanker, and won't turn off the backlight
          when using the X Window system. This also doesn't have anything to
          do with your VESA-compliant power-saving monitor. Further, this
          option doesn't work for all laptops -- it might not turn off your
          backlight at all, or it might print a lot of errors to the console,
          especially if you are using gpm.

config APM_ALLOW_INTS
        bool "Allow interrupts during APM BIOS calls"
        ---help---
          Normally we disable external interrupts while we are making calls to
          the APM BIOS as a measure to lessen the effects of a badly behaving
          BIOS implementation.  The BIOS should reenable interrupts if it
          needs to.  Unfortunately, some BIOSes do not -- especially those in
          many of the newer IBM Thinkpads.  If you experience hangs when you
          suspend, try setting this to Y.  Otherwise, say N.

endif # APM

source "arch/x86/kernel/cpu/cpufreq/Kconfig"

source "drivers/cpuidle/Kconfig"

source "drivers/idle/Kconfig"

endmenu


menu "Bus options (PCI etc.)"

config PCI
        bool "PCI support"
        default y
        select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
        ---help---
          Find out whether you have a PCI motherboard. PCI is the name of a
          bus system, i.e. the way the CPU talks to the other stuff inside
          your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
          VESA. If you have PCI, say Y, otherwise N.

choice
        prompt "PCI access mode"
        depends on X86_32 && PCI
        default PCI_GOANY
        ---help---
          On PCI systems, the BIOS can be used to detect the PCI devices and
          determine their configuration. However, some old PCI motherboards
          have BIOS bugs and may crash if this is done. Also, some embedded
          PCI-based systems don't have any BIOS at all. Linux can also try to
          detect the PCI hardware directly without using the BIOS.

          With this option, you can specify how Linux should detect the
          PCI devices. If you choose "BIOS", the BIOS will be used,
          if you choose "Direct", the BIOS won't be used, and if you
          choose "MMConfig", then PCI Express MMCONFIG will be used.
          If you choose "Any", the kernel will try MMCONFIG, then the
          direct access method and falls back to the BIOS if that doesn't
          work. If unsure, go with the default, which is "Any".

config PCI_GOBIOS
        bool "BIOS"

config PCI_GOMMCONFIG
        bool "MMConfig"

config PCI_GODIRECT
        bool "Direct"

config PCI_GOOLPC
        bool "OLPC"
        depends on OLPC

config PCI_GOANY
        bool "Any"

endchoice

config PCI_BIOS
        def_bool y
        depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)

# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
config PCI_DIRECT
        def_bool y
        depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))

config PCI_MMCONFIG
        def_bool y
        depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)

config PCI_OLPC
        def_bool y
        depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)

config PCI_DOMAINS
        def_bool y
        depends on PCI

config PCI_MMCONFIG
        bool "Support mmconfig PCI config space access"
        depends on X86_64 && PCI && ACPI

config PCI_CNB20LE_QUIRK
        bool "Read CNB20LE Host Bridge Windows"
        depends on PCI
        help
          Read the PCI windows out of the CNB20LE host bridge. This allows
          PCI hotplug to work on systems with the CNB20LE chipset which do
          not have ACPI.

config DMAR
        bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
        depends on PCI_MSI && ACPI && EXPERIMENTAL
        help
          DMA remapping (DMAR) devices support enables independent address
          translations for Direct Memory Access (DMA) from devices.
          These DMA remapping devices are reported via ACPI tables
          and include PCI device scope covered by these DMA
          remapping devices.

config DMAR_DEFAULT_ON
        def_bool y
        prompt "Enable DMA Remapping Devices by default"
        depends on DMAR
        help
          Selecting this option will enable a DMAR device at boot time if
          one is found. If this option is not selected, DMAR support can
          be enabled by passing intel_iommu=on to the kernel. It is
          recommended you say N here while the DMAR code remains
          experimental.

config DMAR_BROKEN_GFX_WA
        bool "Workaround broken graphics drivers (going away soon)"
        depends on DMAR && BROKEN
        ---help---
          Current Graphics drivers tend to use physical address
          for DMA and avoid using DMA APIs. Setting this config
          option permits the IOMMU driver to set a unity map for
          all the OS-visible memory. Hence the driver can continue
          to use physical addresses for DMA, at least until this
          option is removed in the 2.6.32 kernel.

config DMAR_FLOPPY_WA
        def_bool y
        depends on DMAR
        ---help---
          Floppy disk drivers are known to bypass DMA API calls
          thereby failing to work when IOMMU is enabled. This
          workaround will setup a 1:1 mapping for the first
          16MiB to make floppy (an ISA device) work.

config INTR_REMAP
        bool "Support for Interrupt Remapping (EXPERIMENTAL)"
        depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
        ---help---
          Supports Interrupt remapping for IO-APIC and MSI devices.
          To use x2apic mode in the CPU's which support x2APIC enhancements or
          to support platforms with CPU's having > 8 bit APIC ID, say Y.

source "drivers/pci/pcie/Kconfig"

source "drivers/pci/Kconfig"

# x86_64 have no ISA slots, but do have ISA-style DMA.
config ISA_DMA_API
        def_bool y

if X86_32

config ISA
        bool "ISA support"
        ---help---
          Find out whether you have ISA slots on your motherboard.  ISA is the
          name of a bus system, i.e. the way the CPU talks to the other stuff
          inside your box.  Other bus systems are PCI, EISA, MicroChannel
          (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
          newer boards don't support it.  If you have ISA, say Y, otherwise N.

config EISA
        bool "EISA support"
        depends on ISA
        ---help---
          The Extended Industry Standard Architecture (EISA) bus was
          developed as an open alternative to the IBM MicroChannel bus.

          The EISA bus provided some of the features of the IBM MicroChannel
          bus while maintaining backward compatibility with cards made for
          the older ISA bus.  The EISA bus saw limited use between 1988 and
          1995 when it was made obsolete by the PCI bus.

          Say Y here if you are building a kernel for an EISA-based machine.

          Otherwise, say N.

source "drivers/eisa/Kconfig"

config MCA
        bool "MCA support"
        ---help---
          MicroChannel Architecture is found in some IBM PS/2 machines and
          laptops.  It is a bus system similar to PCI or ISA. See
          <file:Documentation/mca.txt> (and especially the web page given
          there) before attempting to build an MCA bus kernel.

source "drivers/mca/Kconfig"

config SCx200
        tristate "NatSemi SCx200 support"
        ---help---
          This provides basic support for National Semiconductor's
          (now AMD's) Geode processors.  The driver probes for the
          PCI-IDs of several on-chip devices, so its a good dependency
          for other scx200_* drivers.

          If compiled as a module, the driver is named scx200.

config SCx200HR_TIMER
        tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
        depends on SCx200
        default y
        ---help---
          This driver provides a clocksource built upon the on-chip
          27MHz high-resolution timer.  Its also a workaround for
          NSC Geode SC-1100's buggy TSC, which loses time when the
          processor goes idle (as is done by the scheduler).  The
          other workaround is idle=poll boot option.

config OLPC
        bool "One Laptop Per Child support"
        select GPIOLIB
        ---help---
          Add support for detecting the unique features of the OLPC
          XO hardware.

config OLPC_OPENFIRMWARE
        bool "Support for OLPC's Open Firmware"
        depends on !X86_64 && !X86_PAE
        default y if OLPC
        help
          This option adds support for the implementation of Open Firmware
          that is used on the OLPC XO-1 Children's Machine.
          If unsure, say N here.

endif # X86_32

config K8_NB
        def_bool y
        depends on CPU_SUP_AMD && PCI

source "drivers/pcmcia/Kconfig"

source "drivers/pci/hotplug/Kconfig"

endmenu


menu "Executable file formats / Emulations"

source "fs/Kconfig.binfmt"

config IA32_EMULATION
        bool "IA32 Emulation"
        depends on X86_64
        select COMPAT_BINFMT_ELF
        ---help---
          Include code to run 32-bit programs under a 64-bit kernel. You should
          likely turn this on, unless you're 100% sure that you don't have any
          32-bit programs left.

config IA32_AOUT
        tristate "IA32 a.out support"
        depends on IA32_EMULATION
        ---help---
          Support old a.out binaries in the 32bit emulation.

config COMPAT
        def_bool y
        depends on IA32_EMULATION

config COMPAT_FOR_U64_ALIGNMENT
        def_bool COMPAT
        depends on X86_64

config SYSVIPC_COMPAT
        def_bool y
        depends on COMPAT && SYSVIPC

endmenu


config HAVE_ATOMIC_IOMAP
        def_bool y
        depends on X86_32

source "net/Kconfig"

source "drivers/Kconfig"

source "drivers/firmware/Kconfig"

source "fs/Kconfig"

source "arch/x86/Kconfig.debug"

source "security/Kconfig"

source "crypto/Kconfig"

source "arch/x86/kvm/Kconfig"

source "lib/Kconfig"