# # For a description of the syntax of this configuration file, # see Documentation/kbuild/kconfig-language.txt. # # Note: ISA is disabled and will hopefully never be enabled. # If you managed to buy an ISA x86-64 box you'll have to fix all the # ISA drivers you need yourself. # mainmenu "Linux Kernel Configuration" config X86_64 bool default y help Port to the x86-64 architecture. x86-64 is a 64-bit extension to the classical 32-bit x86 architecture. For details see . config 64BIT def_bool y config X86 bool default y config SEMAPHORE_SLEEPERS bool default y config MMU bool default y config ISA bool config SBUS bool config RWSEM_GENERIC_SPINLOCK bool default y config RWSEM_XCHGADD_ALGORITHM bool config GENERIC_HWEIGHT bool default y config GENERIC_CALIBRATE_DELAY bool default y config X86_CMPXCHG bool default y config EARLY_PRINTK bool default y config GENERIC_ISA_DMA bool default y config GENERIC_IOMAP 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" 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_VSMP bool "Support for ScaleMP vSMP" 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. endchoice choice prompt "Processor family" default MK8 config MK8 bool "AMD-Opteron/Athlon64" help Optimize for AMD Opteron/Athlon64/Hammer/K8 CPUs. config MPSC bool "Intel EM64T" help Optimize for Intel Pentium 4 and Xeon CPUs with Intel Extended Memory 64 Technology(EM64T). For details see . config GENERIC_CPU bool "Generic-x86-64" help Generic x86-64 CPU. endchoice # # Define implied options from the CPU selection here # config X86_L1_CACHE_BYTES int default "128" if GENERIC_CPU || MPSC default "64" if MK8 config X86_L1_CACHE_SHIFT int default "7" if GENERIC_CPU || MPSC default "6" if MK8 config X86_INTERNODE_CACHE_BYTES int default "4096" if X86_VSMP default X86_L1_CACHE_BYTES if !X86_VSMP config X86_TSC bool default y config X86_GOOD_APIC bool default y config MICROCODE tristate "/dev/cpu/microcode - Intel CPU microcode support" ---help--- If you say Y here the 'File systems' section, you will be able to update the microcode on Intel processors. 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: . To compile this driver as a module, choose M here: the module will be called microcode. If you use modprobe or kmod you may also want to add the line 'alias char-major-10-184 microcode' to your /etc/modules.conf file. 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. config X86_HT bool depends on SMP && !MK8 default y config MATH_EMULATION bool config MCA bool config EISA bool config X86_IO_APIC bool default y config X86_LOCAL_APIC bool default y 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. 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. Just say Y here, all x86-64 machines support MTRRs. See for more information. 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. If you don't know what to do here, say N. config SCHED_SMT bool "SMT (Hyperthreading) scheduler support" depends on SMP default n 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 SMP 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 NUMA bool "Non Uniform Memory Access (NUMA) Support" depends on SMP 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. This code is recommended on all multiprocessor Opteron systems. If the system is EM64T, you should say N unless your system is EM64T NUMA. config K8_NUMA bool "Old style AMD Opteron NUMA detection" depends on NUMA default y 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 configurtion 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 NODES_SHIFT int default "6" depends on NEED_MULTIPLE_NODES # Dummy CONFIG option to select ACPI_NUMA from drivers/acpi/Kconfig. config X86_64_ACPI_NUMA bool "ACPI NUMA detection" depends on NUMA select ACPI select PCI select ACPI_NUMA default y help Enable ACPI SRAT based node topology detection. config NUMA_EMU bool "NUMA emulation" depends on 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 ARCH_DISCONTIGMEM_ENABLE bool depends on NUMA default y 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 || EXPERIMENTAL) config ARCH_MEMORY_PROBE def_bool y depends on MEMORY_HOTPLUG config ARCH_FLATMEM_ENABLE def_bool y depends on !NUMA source "mm/Kconfig" config HAVE_ARCH_EARLY_PFN_TO_NID def_bool y depends on NUMA config OUT_OF_LINE_PFN_TO_PAGE def_bool y depends on DISCONTIGMEM config NR_CPUS int "Maximum number of CPUs (2-256)" range 2 255 depends on SMP default "8" help This allows you to specify the maximum number of CPUs which this kernel will support. Current maximum is 256 CPUs due to APIC addressing limits. Less depending on the hardware. This is purely to save memory - each supported CPU requires memory in the static kernel configuration. config HOTPLUG_CPU bool "Support for hot-pluggable CPUs (EXPERIMENTAL)" depends on SMP && HOTPLUG && EXPERIMENTAL help Say Y here to experiment with turning CPUs off and on. CPUs can be controlled through /sys/devices/system/cpu/cpu#. Say N if you want to disable CPU hotplug. config ARCH_ENABLE_MEMORY_HOTPLUG def_bool y config HPET_TIMER bool default y 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. 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 . config HPET_EMULATE_RTC bool "Provide RTC interrupt" depends on HPET_TIMER && RTC=y # Mark as embedded because too many people got it wrong. # The code disables itself when not needed. config IOMMU bool "IOMMU support" if EMBEDDED default y select SWIOTLB select AGP depends on PCI 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 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" default y select SWIOTLB depends on 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. # need this always selected by IOMMU for the VIA workaround config SWIOTLB bool config X86_MCE bool "Machine check support" if EMBEDDED default y help Include a machine check error handler to report hardware errors. This version will require the mcelog utility to decode some machine check error logs. See ftp://ftp.x86-64.org/pub/linux/tools/mcelog config X86_MCE_INTEL bool "Intel MCE features" depends on X86_MCE && X86_LOCAL_APIC default y help Additional support for intel specific MCE features such as the thermal monitor. config X86_MCE_AMD bool "AMD MCE features" depends on X86_MCE && X86_LOCAL_APIC default y help Additional support for AMD specific MCE features such as the DRAM Error Threshold. config KEXEC bool "kexec system call (EXPERIMENTAL)" depends on EXPERIMENTAL 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 indepedent of the system firmware. And like a reboot you can start any kernel with it, not just Linux. The name comes from the similiarity 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 help Generate crash dump after being started by kexec. config PHYSICAL_START hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) default "0x1000000" if CRASH_DUMP default "0x200000" help This gives the physical address where the kernel is loaded. Normally for regular kernels this value is 0x200000 (2MB). But in the case of kexec on panic the fail safe kernel needs to run at a different address than the panic-ed kernel. This option is used to set the load address for kernels used to capture crash dump on being kexec'ed after panic. The default value for crash dump kernels is 0x1000000 (16MB). This can also 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. Don't change this unless you know what you are doing. 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//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 REORDER bool "Function reordering" default n help This option enables the toolchain to reorder functions for a more optimal TLB usage. If you have pretty much any version of binutils, this can increase your kernel build time by roughly one minute. config K8_NB def_bool y depends on AGP_AMD64 || IOMMU || (PCI && NUMA) endmenu # # Use the generic interrupt handling code in kernel/irq/: # config GENERIC_HARDIRQS bool default y config GENERIC_IRQ_PROBE bool default y # we have no ISA slots, but we do have ISA-style DMA. config ISA_DMA_API bool default y config GENERIC_PENDING_IRQ bool depends on GENERIC_HARDIRQS && SMP default y menu "Power management options" source kernel/power/Kconfig source "drivers/acpi/Kconfig" source "arch/x86_64/kernel/cpufreq/Kconfig" endmenu menu "Bus options (PCI etc.)" config PCI bool "PCI support" # x86-64 doesn't support PCI BIOS access from long mode so always go direct. config PCI_DIRECT bool depends on PCI default y config PCI_MMCONFIG bool "Support mmconfig PCI config space access" depends on PCI && ACPI source "drivers/pci/pcie/Kconfig" source "drivers/pci/Kconfig" 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" 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 bool depends on IA32_EMULATION default y config SYSVIPC_COMPAT bool depends on COMPAT && SYSVIPC default y endmenu source "net/Kconfig" source drivers/Kconfig source "drivers/firmware/Kconfig" source fs/Kconfig menu "Instrumentation Support" depends on EXPERIMENTAL source "arch/x86_64/oprofile/Kconfig" config KPROBES bool "Kprobes (EXPERIMENTAL)" depends on EXPERIMENTAL && MODULES help Kprobes allows you to trap at almost any kernel address and execute a callback function. register_kprobe() establishes a probepoint and specifies the callback. Kprobes is useful for kernel debugging, non-intrusive instrumentation and testing. If in doubt, say "N". endmenu source "arch/x86_64/Kconfig.debug" source "security/Kconfig" source "crypto/Kconfig" source "lib/Kconfig"