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authorIngo Molnar <mingo@elte.hu>2009-02-05 16:21:53 +0100
committerIngo Molnar <mingo@elte.hu>2009-02-05 22:30:20 +0100
commit8f9ca475c994e4d32f405183d07e8c7eedbdbdb4 (patch)
tree3c2bdf052b53f22cbac9d2b844acbde477fad0c6 /arch/x86/Kconfig
parent4f179d121885142fb907b64956228b369d495958 (diff)
downloadlwn-8f9ca475c994e4d32f405183d07e8c7eedbdbdb4.tar.gz
lwn-8f9ca475c994e4d32f405183d07e8c7eedbdbdb4.zip
x86: clean up arch/x86/Kconfig*
- Consistent alignment of help text - Use the ---help--- keyword everywhere consistently as a visual separator - fix whitespace mismatches Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/Kconfig')
-rw-r--r--arch/x86/Kconfig404
1 files changed, 202 insertions, 202 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 80291f749b66..270ecf90bdb4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -5,7 +5,7 @@ mainmenu "Linux Kernel Configuration for x86"
config 64BIT
bool "64-bit kernel" if ARCH = "x86"
default ARCH = "x86_64"
- help
+ ---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
@@ -235,7 +235,7 @@ config SMP
config SPARSE_IRQ
bool "Support sparse irq numbering"
depends on PCI_MSI || HT_IRQ
- help
+ ---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.
@@ -249,7 +249,7 @@ config NUMA_MIGRATE_IRQ_DESC
bool "Move irq desc when changing irq smp_affinity"
depends on SPARSE_IRQ && NUMA
default n
- help
+ ---help---
This enables moving irq_desc to cpu/node that irq will use handled.
If you don't know what to do here, say N.
@@ -258,19 +258,19 @@ config X86_MPPARSE
bool "Enable MPS table" if ACPI
default y
depends on X86_LOCAL_APIC
- help
+ ---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
+ ---help---
This option is needed for the systems that have more than 8 CPUs
config X86_NON_STANDARD
bool "Support for non-standard x86 platforms"
- help
+ ---help---
If you disable this option then the kernel will only support
standard PC platforms. (which covers the vast majority of
systems out there.)
@@ -285,7 +285,7 @@ config X86_VISWS
bool "SGI 320/540 (Visual Workstation)"
depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
depends on X86_NON_STANDARD
- help
+ ---help---
The SGI Visual Workstation series is an IA32-based workstation
based on SGI systems chips with some legacy PC hardware attached.
@@ -300,7 +300,7 @@ config X86_RDC321X
depends on X86_NON_STANDARD
select M486
select X86_REBOOTFIXUPS
- help
+ ---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.
@@ -309,7 +309,7 @@ config X86_UV
bool "SGI Ultraviolet"
depends on X86_64
depends on X86_NON_STANDARD
- help
+ ---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.
@@ -318,7 +318,7 @@ config X86_VSMP
select PARAVIRT
depends on X86_64 && PCI
depends on X86_NON_STANDARD
- help
+ ---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.
@@ -327,7 +327,7 @@ config X86_ELAN
bool "AMD Elan"
depends on X86_32
depends on X86_NON_STANDARD
- help
+ ---help---
Select this for an AMD Elan processor.
Do not use this option for K6/Athlon/Opteron processors!
@@ -338,8 +338,8 @@ config X86_32_NON_STANDARD
bool "Support non-standard 32-bit SMP architectures"
depends on X86_32 && SMP
depends on X86_NON_STANDARD
- help
- This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
+ ---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.
@@ -349,7 +349,7 @@ config X86_NUMAQ
depends on X86_32_NON_STANDARD
select NUMA
select X86_MPPARSE
- help
+ ---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
@@ -359,14 +359,14 @@ config X86_NUMAQ
config X86_SUMMIT
bool "Summit/EXA (IBM x440)"
depends on X86_32_NON_STANDARD
- help
+ ---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 "Support for Unisys ES7000 IA32 series"
depends on X86_32_NON_STANDARD && X86_BIGSMP
- help
+ ---help---
Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
supposed to run on an IA32-based Unisys ES7000 system.
@@ -374,7 +374,7 @@ config X86_VOYAGER
bool "Voyager (NCR)"
depends on SMP && !PCI && BROKEN
depends on X86_32_NON_STANDARD
- help
+ ---help---
Voyager is an MCA-based 32-way capable SMP architecture proprietary
to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
@@ -387,7 +387,7 @@ config SCHED_OMIT_FRAME_POINTER
def_bool y
prompt "Single-depth WCHAN output"
depends on X86
- help
+ ---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,
@@ -397,7 +397,7 @@ config SCHED_OMIT_FRAME_POINTER
menuconfig PARAVIRT_GUEST
bool "Paravirtualized guest support"
- help
+ ---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.
@@ -411,7 +411,7 @@ config VMI
bool "VMI Guest support"
select PARAVIRT
depends on X86_32
- help
+ ---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
@@ -421,7 +421,7 @@ config KVM_CLOCK
bool "KVM paravirtualized clock"
select PARAVIRT
select PARAVIRT_CLOCK
- help
+ ---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
@@ -431,15 +431,15 @@ config KVM_CLOCK
config KVM_GUEST
bool "KVM Guest support"
select PARAVIRT
- help
- This option enables various optimizations for running under the KVM
- hypervisor.
+ ---help---
+ This option enables various optimizations for running under the KVM
+ hypervisor.
source "arch/x86/lguest/Kconfig"
config PARAVIRT
bool "Enable paravirtualization code"
- help
+ ---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
@@ -452,21 +452,21 @@ config PARAVIRT_CLOCK
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.
+ 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 MEMTEST
bool "Memtest"
- help
+ ---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.
+ 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
@@ -482,21 +482,21 @@ 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>.
+ ---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.
+ 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.
+ Choose N to continue using the legacy 8254 timer.
config HPET_EMULATE_RTC
def_bool y
@@ -507,7 +507,7 @@ config HPET_EMULATE_RTC
config DMI
default y
bool "Enable DMI scanning" if EMBEDDED
- help
+ ---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
@@ -519,7 +519,7 @@ config GART_IOMMU
select SWIOTLB
select AGP
depends on X86_64 && PCI
- help
+ ---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.
@@ -534,7 +534,7 @@ config CALGARY_IOMMU
bool "IBM Calgary IOMMU support"
select SWIOTLB
depends on X86_64 && PCI && EXPERIMENTAL
- help
+ ---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
@@ -552,7 +552,7 @@ config CALGARY_IOMMU_ENABLED_BY_DEFAULT
def_bool y
prompt "Should Calgary be enabled by default?"
depends on CALGARY_IOMMU
- help
+ ---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
@@ -564,7 +564,7 @@ config AMD_IOMMU
select SWIOTLB
select PCI_MSI
depends on X86_64 && PCI && ACPI
- help
+ ---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
@@ -579,7 +579,7 @@ config AMD_IOMMU_STATS
bool "Export AMD IOMMU statistics to debugfs"
depends on AMD_IOMMU
select DEBUG_FS
- help
+ ---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.
@@ -588,7 +588,7 @@ config AMD_IOMMU_STATS
# need this always selected by IOMMU for the VIA workaround
config SWIOTLB
def_bool y if X86_64
- help
+ ---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
@@ -606,7 +606,7 @@ config MAXSMP
depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
select CPUMASK_OFFSTACK
default n
- help
+ ---help---
Configure maximum number of CPUS and NUMA Nodes for this architecture.
If unsure, say N.
@@ -617,7 +617,7 @@ config NR_CPUS
default "4096" if MAXSMP
default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
default "8" if SMP
- help
+ ---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.
@@ -628,7 +628,7 @@ config NR_CPUS
config SCHED_SMT
bool "SMT (Hyperthreading) scheduler support"
depends on X86_HT
- help
+ ---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
@@ -638,7 +638,7 @@ config SCHED_MC
def_bool y
prompt "Multi-core scheduler support"
depends on X86_HT
- help
+ ---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.
@@ -648,7 +648,7 @@ source "kernel/Kconfig.preempt"
config X86_UP_APIC
bool "Local APIC support on uniprocessors"
depends on X86_32 && !SMP && !X86_32_NON_STANDARD
- help
+ ---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
@@ -661,7 +661,7 @@ config X86_UP_APIC
config X86_UP_IOAPIC
bool "IO-APIC support on uniprocessors"
depends on X86_UP_APIC
- help
+ ---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.
@@ -686,7 +686,7 @@ config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
bool "Reroute for broken boot IRQs"
default n
depends on X86_IO_APIC
- help
+ ---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
@@ -726,7 +726,7 @@ config X86_MCE_INTEL
def_bool y
prompt "Intel MCE features"
depends on X86_64 && X86_MCE && X86_LOCAL_APIC
- help
+ ---help---
Additional support for intel specific MCE features such as
the thermal monitor.
@@ -734,14 +734,14 @@ config X86_MCE_AMD
def_bool y
prompt "AMD MCE features"
depends on X86_64 && X86_MCE && X86_LOCAL_APIC
- help
+ ---help---
Additional support for AMD specific MCE features such as
the DRAM Error Threshold.
config X86_MCE_NONFATAL
tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
depends on X86_32 && X86_MCE
- help
+ ---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).
@@ -754,7 +754,7 @@ config X86_MCE_NONFATAL
config X86_MCE_P4THERMAL
bool "check for P4 thermal throttling interrupt."
depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
- help
+ ---help---
Enabling this feature will cause a message to be printed when the P4
enters thermal throttling.
@@ -762,11 +762,11 @@ 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
+ ---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.
+ XFree86 to initialize some video cards via BIOS. Disabling this
+ option saves about 6k.
config TOSHIBA
tristate "Toshiba Laptop support"
@@ -840,33 +840,33 @@ config MICROCODE
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/>.
+ 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.
+ 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
+config MICROCODE_OLD_INTERFACE
def_bool y
depends on MICROCODE
config X86_MSR
tristate "/dev/cpu/*/msr - Model-specific register support"
- help
+ ---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.
@@ -875,7 +875,7 @@ config X86_MSR
config X86_CPUID
tristate "/dev/cpu/*/cpuid - CPU information support"
- help
+ ---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
@@ -927,7 +927,7 @@ config NOHIGHMEM
config HIGHMEM4G
bool "4GB"
depends on !X86_NUMAQ
- help
+ ---help---
Select this if you have a 32-bit processor and between 1 and 4
gigabytes of physical RAM.
@@ -935,7 +935,7 @@ config HIGHMEM64G
bool "64GB"
depends on !M386 && !M486
select X86_PAE
- help
+ ---help---
Select this if you have a 32-bit processor and more than 4
gigabytes of physical RAM.
@@ -946,7 +946,7 @@ choice
prompt "Memory split" if EMBEDDED
default VMSPLIT_3G
depends on X86_32
- help
+ ---help---
Select the desired split between kernel and user memory.
If the address range available to the kernel is less than the
@@ -992,20 +992,20 @@ config HIGHMEM
config X86_PAE
bool "PAE (Physical Address Extension) Support"
depends on X86_32 && !HIGHMEM4G
- help
+ ---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
+ 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
+ ---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".
@@ -1016,7 +1016,7 @@ config NUMA
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
+ ---help---
Enable NUMA (Non Uniform Memory Access) support.
The kernel will try to allocate memory used by a CPU on the
@@ -1039,19 +1039,19 @@ 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.
+ ---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
+ ---help---
Enable ACPI SRAT based node topology detection.
# Some NUMA nodes have memory ranges that span
@@ -1066,7 +1066,7 @@ config NODES_SPAN_OTHER_NODES
config NUMA_EMU
bool "NUMA emulation"
depends on X86_64 && NUMA
- help
+ ---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.
@@ -1079,7 +1079,7 @@ config NODES_SHIFT
default "4" if X86_NUMAQ
default "3"
depends on NEED_MULTIPLE_NODES
- help
+ ---help---
Specify the maximum number of NUMA Nodes available on the target
system. Increases memory reserved to accomodate various tables.
@@ -1134,61 +1134,61 @@ source "mm/Kconfig"
config HIGHPTE
bool "Allocate 3rd-level pagetables from highmem"
depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
- help
+ ---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.
+ 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"
+ 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.
+ ---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"
+ 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.
+ ---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.
+ 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.
+ 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.
+ Say Y if unsure.
config MATH_EMULATION
bool
@@ -1254,7 +1254,7 @@ config MTRR_SANITIZER
def_bool y
prompt "MTRR cleanup support"
depends on MTRR
- help
+ ---help---
Convert MTRR layout from continuous to discrete, so X drivers can
add writeback entries.
@@ -1269,7 +1269,7 @@ config MTRR_SANITIZER_ENABLE_DEFAULT
range 0 1
default "0"
depends on MTRR_SANITIZER
- help
+ ---help---
Enable mtrr cleanup default value
config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
@@ -1277,7 +1277,7 @@ config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
range 0 7
default "1"
depends on MTRR_SANITIZER
- help
+ ---help---
mtrr cleanup spare entries default, it can be changed via
mtrr_spare_reg_nr=N on the kernel command line.
@@ -1285,7 +1285,7 @@ config X86_PAT
bool
prompt "x86 PAT support"
depends on MTRR
- help
+ ---help---
Use PAT attributes to setup page level cache control.
PATs are the modern equivalents of MTRRs and are much more
@@ -1300,20 +1300,20 @@ 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 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.
+ 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
+ ---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
@@ -1333,8 +1333,8 @@ config CC_STACKPROTECTOR
bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
depends on X86_64
select CC_STACKPROTECTOR_ALL
- help
- This option turns on the -fstack-protector GCC feature. This
+ ---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
@@ -1351,7 +1351,7 @@ source kernel/Kconfig.hz
config KEXEC
bool "kexec system call"
- help
+ ---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
@@ -1368,7 +1368,7 @@ config KEXEC
config CRASH_DUMP
bool "kernel crash dumps"
depends on X86_64 || (X86_32 && HIGHMEM)
- help
+ ---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
@@ -1383,7 +1383,7 @@ config KEXEC_JUMP
bool "kexec jump (EXPERIMENTAL)"
depends on EXPERIMENTAL
depends on KEXEC && HIBERNATION && X86_32
- help
+ ---help---
Jump between original kernel and kexeced kernel and invoke
code in physical address mode via KEXEC
@@ -1392,7 +1392,7 @@ config PHYSICAL_START
default "0x1000000" if X86_NUMAQ
default "0x200000" if X86_64
default "0x100000"
- help
+ ---help---
This gives the physical address where the kernel is loaded.
If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
@@ -1433,7 +1433,7 @@ config PHYSICAL_START
config RELOCATABLE
bool "Build a relocatable kernel (EXPERIMENTAL)"
depends on EXPERIMENTAL
- help
+ ---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,
@@ -1453,7 +1453,7 @@ config PHYSICAL_ALIGN
default "0x100000" if X86_32
default "0x200000" if X86_64
range 0x2000 0x400000
- help
+ ---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.
@@ -1486,7 +1486,7 @@ config COMPAT_VDSO
def_bool y
prompt "Compat VDSO support"
depends on X86_32 || IA32_EMULATION
- help
+ ---help---
Map the 32-bit VDSO to the predictable old-style address too.
---help---
Say N here if you are running a sufficiently recent glibc
@@ -1498,7 +1498,7 @@ config COMPAT_VDSO
config CMDLINE_BOOL
bool "Built-in kernel command line"
default n
- help
+ ---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
@@ -1516,7 +1516,7 @@ config CMDLINE
string "Built-in kernel command string"
depends on CMDLINE_BOOL
default ""
- help
+ ---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
@@ -1533,7 +1533,7 @@ config CMDLINE_OVERRIDE
bool "Built-in command line overrides boot loader arguments"
default n
depends on CMDLINE_BOOL
- help
+ ---help---
Set this option to 'Y' to have the kernel ignore the boot loader
command line, and use ONLY the built-in command line.
@@ -1632,7 +1632,7 @@ if APM
config APM_IGNORE_USER_SUSPEND
bool "Ignore USER SUSPEND"
- help
+ ---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.
@@ -1656,7 +1656,7 @@ config APM_DO_ENABLE
config APM_CPU_IDLE
bool "Make CPU Idle calls when idle"
- help
+ ---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
@@ -1667,7 +1667,7 @@ config APM_CPU_IDLE
config APM_DISPLAY_BLANK
bool "Enable console blanking using APM"
- help
+ ---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
@@ -1680,7 +1680,7 @@ config APM_DISPLAY_BLANK
config APM_ALLOW_INTS
bool "Allow interrupts during APM BIOS calls"
- help
+ ---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
@@ -1705,7 +1705,7 @@ config PCI
bool "PCI support"
default y
select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
- help
+ ---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
@@ -1776,7 +1776,7 @@ config PCI_MMCONFIG
config DMAR
bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
- help
+ ---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
@@ -1798,29 +1798,29 @@ config DMAR_GFX_WA
def_bool y
prompt "Support for Graphics workaround"
depends on DMAR
- 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.
+ ---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.
config DMAR_FLOPPY_WA
def_bool y
depends on DMAR
- help
- Floppy disk drivers are know to bypass DMA API calls
- thereby failing to work when IOMMU is enabled. This
- workaround will setup a 1:1 mapping for the first
- 16M to make floppy (an ISA device) work.
+ ---help---
+ Floppy disk drivers are know to bypass DMA API calls
+ thereby failing to work when IOMMU is enabled. This
+ workaround will setup a 1:1 mapping for the first
+ 16M 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.
+ ---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"
@@ -1834,7 +1834,7 @@ if X86_32
config ISA
bool "ISA support"
- help
+ ---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
@@ -1861,7 +1861,7 @@ source "drivers/eisa/Kconfig"
config MCA
bool "MCA support"
- help
+ ---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
@@ -1871,7 +1871,7 @@ source "drivers/mca/Kconfig"
config SCx200
tristate "NatSemi SCx200 support"
- help
+ ---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
@@ -1883,7 +1883,7 @@ config SCx200HR_TIMER
tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
depends on SCx200 && GENERIC_TIME
default y
- help
+ ---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
@@ -1894,7 +1894,7 @@ config GEODE_MFGPT_TIMER
def_bool y
prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
- help
+ ---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
@@ -1903,7 +1903,7 @@ config GEODE_MFGPT_TIMER
config OLPC
bool "One Laptop Per Child support"
default n
- help
+ ---help---
Add support for detecting the unique features of the OLPC
XO hardware.
@@ -1928,16 +1928,16 @@ config IA32_EMULATION
bool "IA32 Emulation"
depends on X86_64
select COMPAT_BINFMT_ELF
- help
+ ---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.
+ tristate "IA32 a.out support"
+ depends on IA32_EMULATION
+ ---help---
+ Support old a.out binaries in the 32bit emulation.
config COMPAT
def_bool y