bool
default y
+config GENERIC_TIME
+ bool
+ default y
+
+config GENERIC_TIME_VSYSCALL
+ bool
+ default y
+
config ZONE_DMA32
bool
default y
Optimize for Intel Pentium 4 and older Nocona/Dempsey Xeon CPUs
with Intel Extended Memory 64 Technology(EM64T). For details see
<http://www.intel.com/technology/64bitextensions/>.
- Note the the latest Xeons (Xeon 51xx and 53xx) are not based on the
- Netburst core and shouldn't use this option. You can distingush them
+ Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
+ Netburst core and shouldn't use this option. You can distinguish them
using the cpu family field
- in /proc/cpuinfo. Family 15 is a older Xeon, Family 6 a newer one
- (this rule only applies to system that support EM64T)
+ in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one
+ (this rule only applies to systems that support EM64T)
config MCORE2
bool "Intel Core2 / newer Xeon"
help
Optimize for Intel Core2 and newer Xeons (51xx)
- You can distingush the newer Xeons from the older ones using
- the cpu family field in /proc/cpuinfo. 15 is a older Xeon
+ You can distinguish the newer Xeons from the older ones using
+ the cpu family field in /proc/cpuinfo. 15 is an older Xeon
(use CONFIG_MPSC then), 6 is a newer one. This rule only
applies to CPUs that support EM64T.
depends on DISCONTIGMEM
config NR_CPUS
- int "Maximum number of CPUs (2-256)"
+ int "Maximum number of CPUs (2-255)"
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
+ kernel will support. Current maximum is 255 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)"
+ bool "Support for suspend on SMP and 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.
+ This is also required for suspend/hibernation on SMP systems.
+
+ Say N if you want to disable CPU hotplug and don't need to
+ suspend.
config ARCH_ENABLE_MEMORY_HOTPLUG
def_bool y
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.
+ 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.
# need this always selected by IOMMU for the VIA workaround
config SWIOTLB
bool
+ 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 X86_MCE
bool "Machine check support" if EMBEDDED
PHYSICAL_START.
For more details see Documentation/kdump/kdump.txt
+config RELOCATABLE
+ bool "Build a relocatable kernel(EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ help
+ Builds a relocatable kernel. This enables loading and running
+ a kernel binary from a different physical address than it has
+ been compiled for.
+
+ 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 kernel run from the address
+ it has been loaded at and compile time physical address
+ (CONFIG_PHYSICAL_START) is ignored.
+
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
+ This gives the physical address where the kernel is loaded. It
+ should be aligned to 2MB boundary.
+
+ 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.
+
+ So if you are using bzImage for capturing the crash dump, leave
+ the value here unchanged to 0x200000 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 advantageous as
+ one does not have to build two kernels. Same kernel can be used
+ as production kernel and capture kernel.
+
Don't change this unless you know what you are doing.
config SECCOMP
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)
config PCI
bool "PCI support"
+ select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
config PCI_DIRECT