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+#
+# For a description of the syntax of this configuration file,
+# see Documentation/kbuild/kconfig-language.txt.
+#
+
+mainmenu "Linux Kernel Configuration"
+
+config X86_32
+ bool
+ default y
+ help
+ This is Linux's home port. Linux was originally native to the Intel
+ 386, and runs on all the later x86 processors including the Intel
+ 486, 586, Pentiums, and various instruction-set-compatible chips by
+ AMD, Cyrix, and others.
+
+config GENERIC_TIME
+ bool
+ default y
+
+config GENERIC_CMOS_UPDATE
+ bool
+ default y
+
+config CLOCKSOURCE_WATCHDOG
+ bool
+ default y
+
+config GENERIC_CLOCKEVENTS
+ bool
+ default y
+
+config GENERIC_CLOCKEVENTS_BROADCAST
+ bool
+ default y
+ depends on X86_LOCAL_APIC
+
+config LOCKDEP_SUPPORT
+ bool
+ default y
+
+config STACKTRACE_SUPPORT
+ bool
+ default y
+
+config SEMAPHORE_SLEEPERS
+ bool
+ default y
+
+config X86
+ bool
+ default y
+
+config MMU
+ bool
+ default y
+
+config ZONE_DMA
+ bool
+ default y
+
+config QUICKLIST
+ bool
+ default y
+
+config SBUS
+ bool
+
+config GENERIC_ISA_DMA
+ bool
+ default y
+
+config GENERIC_IOMAP
+ bool
+ default y
+
+config GENERIC_BUG
+ bool
+ default y
+ depends on BUG
+
+config GENERIC_HWEIGHT
+ bool
+ default y
+
+config ARCH_MAY_HAVE_PC_FDC
+ bool
+ default y
+
+config DMI
+ bool
+ default y
+
+source "init/Kconfig"
+
+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 the <file:Documentation/smp.txt>,
+ <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.
+
+choice
+ prompt "Subarchitecture Type"
+ default X86_PC
+
+config X86_PC
+ bool "PC-compatible"
+ help
+ Choose this option if your computer is a standard PC or compatible.
+
+config X86_ELAN
+ bool "AMD Elan"
+ 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_VOYAGER
+ bool "Voyager (NCR)"
+ select SMP if !BROKEN
+ help
+ Voyager is an MCA-based 32-way capable SMP architecture proprietary
+ to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
+
+ *** WARNING ***
+
+ If you do not specifically know you have a Voyager based machine,
+ say N here, otherwise the kernel you build will not be bootable.
+
+config X86_NUMAQ
+ bool "NUMAQ (IBM/Sequent)"
+ select SMP
+ select NUMA
+ help
+ This option is used for getting Linux to run on a (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_SUMMIT
+ bool "Summit/EXA (IBM x440)"
+ depends on SMP
+ help
+ This option is needed for IBM systems that use the Summit/EXA chipset.
+ In particular, it is needed for the x440.
+
+ If you don't have one of these computers, you should say N here.
+ If you want to build a NUMA kernel, you must select ACPI.
+
+config X86_BIGSMP
+ bool "Support for other sub-arch SMP systems with more than 8 CPUs"
+ depends on SMP
+ help
+ This option is needed for the systems that have more than 8 CPUs
+ and if the system is not of any sub-arch type above.
+
+ If you don't have such a system, you should say N here.
+
+config X86_VISWS
+ bool "SGI 320/540 (Visual Workstation)"
+ 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 not run on PCs
+ and vice versa. See <file:Documentation/sgi-visws.txt> for details.
+
+config X86_GENERICARCH
+ bool "Generic architecture (Summit, bigsmp, ES7000, default)"
+ help
+ This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
+ It is intended for a generic binary kernel.
+ If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
+
+config X86_ES7000
+ bool "Support for Unisys ES7000 IA32 series"
+ depends on SMP
+ help
+ Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
+ supposed to run on an IA32-based Unisys ES7000 system.
+ Only choose this option if you have such a system, otherwise you
+ should say N here.
+
+endchoice
+
+config SCHED_NO_NO_OMIT_FRAME_POINTER
+ bool "Single-depth WCHAN output"
+ default y
+ 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".
+
+config PARAVIRT
+ bool
+ depends on !(X86_VISWS || X86_VOYAGER)
+ 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.
+
+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"
+ select PARAVIRT
+ depends on !(X86_VISWS || X86_VOYAGER)
+ 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.
+
+source "arch/x86/lguest/Kconfig"
+
+endif
+
+config ACPI_SRAT
+ bool
+ default y
+ depends on ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
+ select ACPI_NUMA
+
+config HAVE_ARCH_PARSE_SRAT
+ bool
+ default y
+ depends on ACPI_SRAT
+
+config X86_SUMMIT_NUMA
+ bool
+ default y
+ depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
+
+config X86_CYCLONE_TIMER
+ bool
+ default y
+ depends on X86_SUMMIT || X86_GENERICARCH
+
+config ES7000_CLUSTERED_APIC
+ bool
+ default y
+ depends on SMP && X86_ES7000 && MPENTIUMIII
+
+source "arch/x86/Kconfig.cpu"
+
+config HPET_TIMER
+ bool "HPET Timer Support"
+ help
+ This enables the use of the HPET for the kernel's internal timer.
+ HPET is the next generation timer replacing legacy 8254s.
+ 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
+ bool
+ depends on HPET_TIMER && RTC=y
+ default y
+
+config NR_CPUS
+ int "Maximum number of CPUs (2-255)"
+ range 2 255
+ depends on SMP
+ default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
+ default "8"
+ help
+ This allows you to specify the maximum number of CPUs which this
+ kernel will support. The maximum supported value is 255 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
+ bool "Multi-core scheduler support"
+ depends on X86_HT
+ default y
+ 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.
+
+source "kernel/Kconfig.preempt"
+
+config X86_UP_APIC
+ bool "Local APIC support on uniprocessors"
+ depends on !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
+ 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
+ bool
+ depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH
+ default y
+
+config X86_IO_APIC
+ bool
+ depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH
+ default y
+
+config X86_VISWS_APIC
+ bool
+ depends on X86_VISWS
+ default y
+
+config X86_MCE
+ bool "Machine Check Exception"
+ depends on !X86_VOYAGER
+ ---help---
+ Machine Check Exception support allows the processor to notify the
+ kernel if it detects a problem (e.g. overheating, component failure).
+ The action the kernel takes depends on the severity of the problem,
+ ranging from a warning message on the console, to halting the machine.
+ Your processor must be a Pentium or newer to support this - check the
+ flags in /proc/cpuinfo for mce. Note that some older Pentium systems
+ have a design flaw which leads to false MCE events - hence MCE is
+ disabled on all P5 processors, unless explicitly enabled with "mce"
+ as a boot argument. Similarly, if MCE is built in and creates a
+ problem on some new non-standard machine, you can boot with "nomce"
+ to disable it. MCE support simply ignores non-MCE processors like
+ the 386 and 486, so nearly everyone can say Y here.
+
+config X86_MCE_NONFATAL
+ tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
+ depends on X86_MCE
+ help
+ Enabling this feature starts a timer that triggers every 5 seconds which
+ will look at the machine check registers to see if anything happened.
+ Non-fatal problems automatically get corrected (but still logged).
+ Disable this if you don't want to see these messages.
+ Seeing the messages this option prints out may be indicative of dying
+ or out-of-spec (ie, overclocked) hardware.
+ This option only does something on certain CPUs.
+ (AMD Athlon/Duron and Intel Pentium 4)
+
+config X86_MCE_P4THERMAL
+ bool "check for P4 thermal throttling interrupt."
+ depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
+ help
+ Enabling this feature will cause a message to be printed when the P4
+ enters thermal throttling.
+
+config VM86
+ default y
+ bool "Enable VM86 support" if EMBEDDED
+ 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"
+ ---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
+ default n
+ ---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.
+
+ 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 - Intel IA32 CPU microcode support"
+ select FW_LOADER
+ ---help---
+ If you say Y here, you will be able to update the microcode on
+ Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
+ Pentium III, Pentium 4, Xeon etc. You will obviously need the
+ actual microcode binary data itself which is not shipped with the
+ Linux kernel.
+
+ For latest news and information on obtaining all the required
+ ingredients for this driver, check:
+ <http://www.urbanmyth.org/microcode/>.
+
+ To compile this driver as a module, choose M here: the
+ module will be called microcode.
+
+config MICROCODE_OLD_INTERFACE
+ bool
+ depends on MICROCODE
+ default y
+
+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.
+
+source "drivers/firmware/Kconfig"
+
+choice
+ prompt "High Memory Support"
+ default HIGHMEM4G if !X86_NUMAQ
+ default HIGHMEM64G if X86_NUMAQ
+
+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
+ 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
+
+config HIGHMEM
+ bool
+ depends on HIGHMEM64G || HIGHMEM4G
+ default y
+
+config X86_PAE
+ bool "PAE (Physical Address Extension) Support"
+ default n
+ depends on !HIGHMEM4G
+ select RESOURCES_64BIT
+ 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.
+
+# Common NUMA Features
+config NUMA
+ bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
+ depends on SMP && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL
+ default n if X86_PC
+ default y if (X86_NUMAQ || X86_SUMMIT)
+ help
+ NUMA support for i386. This is currently highly experimental
+ and should be only used for kernel development. It might also
+ cause boot failures.
+
+comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
+ depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
+
+config NODES_SHIFT
+ int
+ default "4" if X86_NUMAQ
+ default "3"
+ depends on NEED_MULTIPLE_NODES
+
+config HAVE_ARCH_BOOTMEM_NODE
+ bool
+ depends on NUMA
+ default y
+
+config ARCH_HAVE_MEMORY_PRESENT
+ bool
+ depends on DISCONTIGMEM
+ default y
+
+config NEED_NODE_MEMMAP_SIZE
+ bool
+ depends on DISCONTIGMEM || SPARSEMEM
+ default y
+
+config HAVE_ARCH_ALLOC_REMAP
+ bool
+ depends on NUMA
+ default y
+
+config ARCH_FLATMEM_ENABLE
+ def_bool y
+ depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
+
+config ARCH_DISCONTIGMEM_ENABLE
+ def_bool y
+ depends on NUMA
+
+config ARCH_DISCONTIGMEM_DEFAULT
+ def_bool y
+ depends on NUMA
+
+config ARCH_SPARSEMEM_ENABLE
+ def_bool y
+ depends on (NUMA || (X86_PC && EXPERIMENTAL))
+ select SPARSEMEM_STATIC
+
+config ARCH_SELECT_MEMORY_MODEL
+ def_bool y
+ depends on ARCH_SPARSEMEM_ENABLE
+
+config ARCH_POPULATES_NODE_MAP
+ def_bool y
+
+source "mm/Kconfig"
+
+config HIGHPTE
+ bool "Allocate 3rd-level pagetables from highmem"
+ depends on HIGHMEM4G || HIGHMEM64G
+ 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 MATH_EMULATION
+ bool "Math emulation"
+ ---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
+ bool "MTRR (Memory Type Range Register) support"
+ ---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/mtrr.txt> for more information.
+
+config EFI
+ bool "Boot from EFI support"
+ depends on ACPI
+ default n
+ ---help---
+ This enables the kernel to boot on EFI platforms using
+ system configuration information passed to it from the firmware.
+ This also enables the kernel to use any EFI runtime services that are
+ available (such as the EFI variable services).
+
+ This option is only useful on systems that have EFI firmware
+ and will result in a kernel image that is ~8k larger. In addition,
+ you must use the latest ELILO loader available at
+ <http://elilo.sourceforge.net> in order to take advantage of
+ kernel initialization using EFI information (neither GRUB nor LILO know
+ anything about EFI). However, even with this option, the resultant
+ kernel should continue to boot on existing non-EFI platforms.
+
+config IRQBALANCE
+ bool "Enable kernel irq balancing"
+ depends on SMP && X86_IO_APIC
+ default y
+ help
+ The default yes will allow the kernel to do irq load balancing.
+ Saying no will keep the kernel from doing irq load balancing.
+
+# turning this on wastes a bunch of space.
+# Summit needs it only when NUMA is on
+config BOOT_IOREMAP
+ bool
+ depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
+ default y
+
+config SECCOMP
+ bool "Enable seccomp to safely compute untrusted bytecode"
+ depends on PROC_FS
+ default y
+ 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 /proc/<pid>/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.
+
+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 (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ depends on 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 PHYSICAL_START
+ hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
+ default "0x1000000" if X86_NUMAQ
+ default "0x100000"
+ 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 0x100000 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 (Typically 16MB
+ 0x1000000). 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. Typically this parameter is set as
+ crashkernel=64M@16M. 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 (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ 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.
+
+config PHYSICAL_ALIGN
+ hex "Alignment value to which kernel should be aligned"
+ default "0x100000"
+ range 0x2000 0x400000
+ 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 suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
+ depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
+ ---help---
+ Say Y here to experiment with turning CPUs off and on, and to
+ enable suspend on SMP systems. CPUs can be controlled through
+ /sys/devices/system/cpu.
+
+config COMPAT_VDSO
+ bool "Compat VDSO support"
+ default y
+ help
+ Map the VDSO to the predictable old-style address too.
+ ---help---
+ 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.
+
+endmenu
+
+config ARCH_ENABLE_MEMORY_HOTPLUG
+ def_bool y
+ depends on HIGHMEM
+
+menu "Power management options (ACPI, APM)"
+ depends on !X86_VOYAGER
+
+source kernel/power/Kconfig
+
+source "drivers/acpi/Kconfig"
+
+menuconfig APM
+ tristate "APM (Advanced Power Management) BIOS support"
+ depends on PM_SLEEP && !X86_VISWS
+ ---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/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.
+
+config APM_REAL_MODE_POWER_OFF
+ bool "Use real mode APM BIOS call to power off"
+ help
+ Use real mode APM BIOS calls to switch off the computer. This is
+ a work-around for a number of buggy BIOSes. Switch this option on if
+ your computer crashes instead of powering off properly.
+
+endif # APM
+
+source "arch/x86/kernel/cpu/cpufreq/Kconfig_32"
+
+source "drivers/cpuidle/Kconfig"
+
+endmenu
+
+menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
+
+config PCI
+ bool "PCI support" if !X86_VISWS
+ depends on !X86_VOYAGER
+ default y if X86_VISWS
+ 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.
+
+ The PCI-HOWTO, available from
+ <http://www.tldp.org/docs.html#howto>, contains valuable
+ information about which PCI hardware does work under Linux and which
+ doesn't.
+
+choice
+ prompt "PCI access mode"
+ depends on PCI && !X86_VISWS
+ 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_GOANY
+ bool "Any"
+
+endchoice
+
+config PCI_BIOS
+ bool
+ depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
+ default y
+
+config PCI_DIRECT
+ bool
+ depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
+ default y
+
+config PCI_MMCONFIG
+ bool
+ depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
+ default y
+
+config PCI_DOMAINS
+ bool
+ depends on PCI
+ default y
+
+source "drivers/pci/pcie/Kconfig"
+
+source "drivers/pci/Kconfig"
+
+config ISA_DMA_API
+ bool
+ default y
+
+config ISA
+ bool "ISA support"
+ depends on !(X86_VOYAGER || X86_VISWS)
+ 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" if !(X86_VISWS || X86_VOYAGER)
+ default y if X86_VOYAGER
+ 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"
+ depends on !X86_VOYAGER
+ 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 && GENERIC_TIME
+ 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 GEODE_MFGPT_TIMER
+ bool "Geode Multi-Function General Purpose Timer (MFGPT) events"
+ depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
+ default y
+ help
+ This driver provides a clock event source based on the MFGPT
+ timer(s) in the CS5535 and CS5536 companion chip for the geode.
+ MFGPTs have a better resolution and max interval than the
+ generic PIT, and are suitable for use as high-res timers.
+
+config K8_NB
+ def_bool y
+ depends on AGP_AMD64
+
+source "drivers/pcmcia/Kconfig"
+
+source "drivers/pci/hotplug/Kconfig"
+
+endmenu
+
+menu "Executable file formats"
+
+source "fs/Kconfig.binfmt"
+
+endmenu
+
+source "net/Kconfig"
+
+source "drivers/Kconfig"
+
+source "fs/Kconfig"
+
+source "kernel/Kconfig.instrumentation"
+
+source "arch/x86/Kconfig.debug"
+
+source "security/Kconfig"
+
+source "crypto/Kconfig"
+
+source "lib/Kconfig"
+
+#
+# Use the generic interrupt handling code in kernel/irq/:
+#
+config GENERIC_HARDIRQS
+ bool
+ default y
+
+config GENERIC_IRQ_PROBE
+ bool
+ default y
+
+config GENERIC_PENDING_IRQ
+ bool
+ depends on GENERIC_HARDIRQS && SMP
+ default y
+
+config X86_SMP
+ bool
+ depends on SMP && !X86_VOYAGER
+ default y
+
+config X86_HT
+ bool
+ depends on SMP && !(X86_VISWS || X86_VOYAGER)
+ default y
+
+config X86_BIOS_REBOOT
+ bool
+ depends on !(X86_VISWS || X86_VOYAGER)
+ default y
+
+config X86_TRAMPOLINE
+ bool
+ depends on X86_SMP || (X86_VOYAGER && SMP)
+ default y
+
+config KTIME_SCALAR
+ bool
+ default y
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