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Kernel Parameters
~~~~~~~~~~~~~~~~~
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The following is a consolidated list of the kernel parameters as
implemented by the __setup(), core_param() and module_param() macros
and sorted into English Dictionary order (defined as ignoring all
punctuation and sorting digits before letters in a case insensitive
manner), and with descriptions where known.
The kernel parses parameters from the kernel command line up to "--";
if it doesn't recognize a parameter and it doesn't contain a '.', the
parameter gets passed to init: parameters with '=' go into init's
environment, others are passed as command line arguments to init.
Everything after "--" is passed as an argument to init.
Module parameters can be specified in two ways: via the kernel command
line with a module name prefix, or via modprobe, e.g.:
(kernel command line) usbcore.blinkenlights=1
(modprobe command line) modprobe usbcore blinkenlights=1
Parameters for modules which are built into the kernel need to be
specified on the kernel command line. modprobe looks through the
kernel command line (/proc/cmdline) and collects module parameters
when it loads a module, so the kernel command line can be used for
loadable modules too.
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Hyphens (dashes) and underscores are equivalent in parameter names, so
log_buf_len=1M print-fatal-signals=1
can also be entered as
log-buf-len=1M print_fatal_signals=1
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Double-quotes can be used to protect spaces in values, e.g.:
param="spaces in here"
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This document may not be entirely up to date and comprehensive. The command
"modinfo -p ${modulename}" shows a current list of all parameters of a loadable
module. Loadable modules, after being loaded into the running kernel, also
reveal their parameters in /sys/module/${modulename}/parameters/. Some of these
parameters may be changed at runtime by the command
"echo -n ${value} > /sys/module/${modulename}/parameters/${parm}".
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The parameters listed below are only valid if certain kernel build options were
enabled and if respective hardware is present. The text in square brackets at
the beginning of each description states the restrictions within which a
parameter is applicable:
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ACPI ACPI support is enabled.
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AGP AGP (Accelerated Graphics Port) is enabled.
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ALSA ALSA sound support is enabled.
APIC APIC support is enabled.
APM Advanced Power Management support is enabled.
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ARM ARM architecture is enabled.
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AVR32 AVR32 architecture is enabled.
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AX25 Appropriate AX.25 support is enabled.
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BLACKFIN Blackfin architecture is enabled.
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CLK Common clock infrastructure is enabled.
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CMA Contiguous Memory Area support is enabled.
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DRM Direct Rendering Management support is enabled.
DYNAMIC_DEBUG Build in debug messages and enable them at runtime
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EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
EFI EFI Partitioning (GPT) is enabled
EIDE EIDE/ATAPI support is enabled.
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EVM Extended Verification Module
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FB The frame buffer device is enabled.
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FTRACE Function tracing enabled.
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GCOV GCOV profiling is enabled.
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HW Appropriate hardware is enabled.
IA-64 IA-64 architecture is enabled.
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IMA Integrity measurement architecture is enabled.
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IOSCHED More than one I/O scheduler is enabled.
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IP_PNP IP DHCP, BOOTP, or RARP is enabled.
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IPV6 IPv6 support is enabled.
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ISAPNP ISA PnP code is enabled.
ISDN Appropriate ISDN support is enabled.
JOY Appropriate joystick support is enabled.
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KGDB Kernel debugger support is enabled.
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KVM Kernel Virtual Machine support is enabled.
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LIBATA Libata driver is enabled
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LP Printer support is enabled.
LOOP Loopback device support is enabled.
M68k M68k architecture is enabled.
These options have more detailed description inside of
Documentation/m68k/kernel-options.txt.
MDA MDA console support is enabled.
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MIPS MIPS architecture is enabled.
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MOUSE Appropriate mouse support is enabled.
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MSI Message Signaled Interrupts (PCI).
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MTD MTD (Memory Technology Device) support is enabled.
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NET Appropriate network support is enabled.
NUMA NUMA support is enabled.
NFS Appropriate NFS support is enabled.
OSS OSS sound support is enabled.
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PV_OPS A paravirtualized kernel is enabled.
PARIDE The ParIDE (parallel port IDE) subsystem is enabled.
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PARISC The PA-RISC architecture is enabled.
PCI PCI bus support is enabled.
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PCIE PCI Express support is enabled.
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PCMCIA The PCMCIA subsystem is enabled.
PNP Plug & Play support is enabled.
PPC PowerPC architecture is enabled.
PPT Parallel port support is enabled.
PS2 Appropriate PS/2 support is enabled.
RAM RAM disk support is enabled.
S390 S390 architecture is enabled.
SCSI Appropriate SCSI support is enabled.
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A lot of drivers have their options described inside
the Documentation/scsi/ sub-directory.
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SECURITY Different security models are enabled.
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SELINUX SELinux support is enabled.
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APPARMOR AppArmor support is enabled.
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SERIAL Serial support is enabled.
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SH SuperH architecture is enabled.
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SMP The kernel is an SMP kernel.
SPARC Sparc architecture is enabled.
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SWSUSP Software suspend (hibernation) is enabled.
SUSPEND System suspend states are enabled.
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TPM TPM drivers are enabled.
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TS Appropriate touchscreen support is enabled.
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UMS USB Mass Storage support is enabled.
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USB USB support is enabled.
USBHID USB Human Interface Device support is enabled.
V4L Video For Linux support is enabled.
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VMMIO Driver for memory mapped virtio devices is enabled.
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VGA The VGA console has been enabled.
VT Virtual terminal support is enabled.
WDT Watchdog support is enabled.
XT IBM PC/XT MFM hard disk support is enabled.
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X86-32 X86-32, aka i386 architecture is enabled.
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X86-64 X86-64 architecture is enabled.
More X86-64 boot options can be found in
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Documentation/x86/x86_64/boot-options.txt .
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X86 Either 32-bit or 64-bit x86 (same as X86-32+X86-64)
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XEN Xen support is enabled
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In addition, the following text indicates that the option:
BUGS= Relates to possible processor bugs on the said processor.
KNL Is a kernel start-up parameter.
BOOT Is a boot loader parameter.
Parameters denoted with BOOT are actually interpreted by the boot
loader, and have no meaning to the kernel directly.
Do not modify the syntax of boot loader parameters without extreme
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need or coordination with <Documentation/x86/boot.txt>.
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There are also arch-specific kernel-parameters not documented here.
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See for example <Documentation/x86/x86_64/boot-options.txt>.
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Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
a trailing = on the name of any parameter states that that parameter will
be entered as an environment variable, whereas its absence indicates that
it will appear as a kernel argument readable via /proc/cmdline by programs
running once the system is up.
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The number of kernel parameters is not limited, but the length of the
complete command line (parameters including spaces etc.) is limited to
a fixed number of characters. This limit depends on the architecture
and is between 256 and 4096 characters. It is defined in the file
./include/asm/setup.h as COMMAND_LINE_SIZE.
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Finally, the [KMG] suffix is commonly described after a number of kernel
parameter values. These 'K', 'M', and 'G' letters represent the _binary_
multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30
bytes respectively. Such letter suffixes can also be entirely omitted.
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acpi= [HW,ACPI,X86]
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Advanced Configuration and Power Interface
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Format: { force | off | strict | noirq | rsdt }
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force -- enable ACPI if default was off
off -- disable ACPI if default was on
noirq -- do not use ACPI for IRQ routing
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strict -- Be less tolerant of platforms that are not
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strictly ACPI specification compliant.
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rsdt -- prefer RSDT over (default) XSDT
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copy_dsdt -- copy DSDT to memory
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See also Documentation/power/runtime_pm.txt, pci=noacpi
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acpi_rsdp= [ACPI,EFI,KEXEC]
Pass the RSDP address to the kernel, mostly used
on machines running EFI runtime service to boot the
second kernel for kdump.
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acpi_apic_instance= [ACPI, IOAPIC]
Format: <int>
2: use 2nd APIC table, if available
1,0: use 1st APIC table
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default: 0
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acpi_backlight= [HW,ACPI]
acpi_backlight=vendor
acpi_backlight=video
If set to vendor, prefer vendor specific driver
(e.g. thinkpad_acpi, sony_acpi, etc.) instead
of the ACPI video.ko driver.
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acpi.debug_layer= [HW,ACPI,ACPI_DEBUG]
acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
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Format: <int>
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CONFIG_ACPI_DEBUG must be enabled to produce any ACPI
debug output. Bits in debug_layer correspond to a
_COMPONENT in an ACPI source file, e.g.,
#define _COMPONENT ACPI_PCI_COMPONENT
Bits in debug_level correspond to a level in
ACPI_DEBUG_PRINT statements, e.g.,
ACPI_DEBUG_PRINT((ACPI_DB_INFO, ...
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The debug_level mask defaults to "info". See
Documentation/acpi/debug.txt for more information about
debug layers and levels.
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Enable processor driver info messages:
acpi.debug_layer=0x20000000
Enable PCI/PCI interrupt routing info messages:
acpi.debug_layer=0x400000
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Enable AML "Debug" output, i.e., stores to the Debug
object while interpreting AML:
acpi.debug_layer=0xffffffff acpi.debug_level=0x2
Enable all messages related to ACPI hardware:
acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
Some values produce so much output that the system is
unusable. The "log_buf_len" parameter may be useful
if you need to capture more output.
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acpi_force_table_verification [HW,ACPI]
Enable table checksum verification during early stage.
By default, this is disabled due to x86 early mapping
size limitation.
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acpi_irq_balance [HW,ACPI]
ACPI will balance active IRQs
default in APIC mode
acpi_irq_nobalance [HW,ACPI]
ACPI will not move active IRQs (default)
default in PIC mode
acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
Format: <irq>,<irq>...
acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
use by PCI
Format: <irq>,<irq>...
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acpi_no_auto_serialize [HW,ACPI]
Disable auto-serialization of AML methods
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AML control methods that contain the opcodes to create
named objects will be marked as "Serialized" by the
auto-serialization feature.
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This feature is enabled by default.
This option allows to turn off the feature.
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acpi_no_static_ssdt [HW,ACPI]
Disable installation of static SSDTs at early boot time
By default, SSDTs contained in the RSDT/XSDT will be
installed automatically and they will appear under
/sys/firmware/acpi/tables.
This option turns off this feature.
Note that specifying this option does not affect
dynamic table installation which will install SSDT
tables to /sys/firmware/acpi/tables/dynamic.
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acpica_no_return_repair [HW, ACPI]
Disable AML predefined validation mechanism
This mechanism can repair the evaluation result to make
the return objects more ACPI specification compliant.
This option is useful for developers to identify the
root cause of an AML interpreter issue when the issue
has something to do with the repair mechanism.
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acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
Format: To spoof as Windows 98: ="Microsoft Windows"
acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
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acpi_osi="string1" # add string1
acpi_osi="!string2" # remove string2
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acpi_osi=!* # remove all strings
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acpi_osi=! # disable all built-in OS vendor
strings
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acpi_osi= # disable all strings
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'acpi_osi=!' can be used in combination with single or
multiple 'acpi_osi="string1"' to support specific OS
vendor string(s). Note that such command can only
affect the default state of the OS vendor strings, thus
it cannot affect the default state of the feature group
strings and the current state of the OS vendor strings,
specifying it multiple times through kernel command line
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is meaningless. This command is useful when one do not
care about the state of the feature group strings which
should be controlled by the OSPM.
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Examples:
1. 'acpi_osi=! acpi_osi="Windows 2000"' is equivalent
to 'acpi_osi="Windows 2000" acpi_osi=!', they all
can make '_OSI("Windows 2000")' TRUE.
'acpi_osi=' cannot be used in combination with other
'acpi_osi=' command lines, the _OSI method will not
exist in the ACPI namespace. NOTE that such command can
only affect the _OSI support state, thus specifying it
multiple times through kernel command line is also
meaningless.
Examples:
1. 'acpi_osi=' can make 'CondRefOf(_OSI, Local1)'
FALSE.
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'acpi_osi=!*' can be used in combination with single or
multiple 'acpi_osi="string1"' to support specific
string(s). Note that such command can affect the
current state of both the OS vendor strings and the
feature group strings, thus specifying it multiple times
through kernel command line is meaningful. But it may
still not able to affect the final state of a string if
there are quirks related to this string. This command
is useful when one want to control the state of the
feature group strings to debug BIOS issues related to
the OSPM features.
Examples:
1. 'acpi_osi="Module Device" acpi_osi=!*' can make
'_OSI("Module Device")' FALSE.
2. 'acpi_osi=!* acpi_osi="Module Device"' can make
'_OSI("Module Device")' TRUE.
3. 'acpi_osi=! acpi_osi=!* acpi_osi="Windows 2000"' is
equivalent to
'acpi_osi=!* acpi_osi=! acpi_osi="Windows 2000"'
and
'acpi_osi=!* acpi_osi="Windows 2000" acpi_osi=!',
they all will make '_OSI("Windows 2000")' TRUE.
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acpi_pm_good [X86]
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Override the pmtimer bug detection: force the kernel
to assume that this machine's pmtimer latches its value
and always returns good values.
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acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Format: { level | edge | high | low }
acpi_skip_timer_override [HW,ACPI]
Recognize and ignore IRQ0/pin2 Interrupt Override.
For broken nForce2 BIOS resulting in XT-PIC timer.
acpi_sleep= [HW,ACPI] Sleep options
Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
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old_ordering, nonvs, sci_force_enable }
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See Documentation/power/video.txt for information on
s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
as soon as the kernel's real-mode entry point is called.
s4_nohwsig prevents ACPI hardware signature from being
used during resume from hibernation.
old_ordering causes the ACPI 1.0 ordering of the _PTS
control method, with respect to putting devices into
low power states, to be enforced (the ACPI 2.0 ordering
of _PTS is used by default).
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nonvs prevents the kernel from saving/restoring the
ACPI NVS memory during suspend/hibernation and resume.
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sci_force_enable causes the kernel to set SCI_EN directly
on resume from S1/S3 (which is against the ACPI spec,
but some broken systems don't work without it).
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acpi_use_timer_override [HW,ACPI]
Use timer override. For some broken Nvidia NF5 boards
that require a timer override, but don't have HPET
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acpi_enforce_resources= [ACPI]
{ strict | lax | no }
Check for resource conflicts between native drivers
and ACPI OperationRegions (SystemIO and SystemMemory
only). IO ports and memory declared in ACPI might be
used by the ACPI subsystem in arbitrary AML code and
can interfere with legacy drivers.
strict (default): access to resources claimed by ACPI
is denied; legacy drivers trying to access reserved
resources will fail to bind to device using them.
lax: access to resources claimed by ACPI is allowed;
legacy drivers trying to access reserved resources
will bind successfully but a warning message is logged.
no: ACPI OperationRegions are not marked as reserved,
no further checks are performed.
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acpi_no_memhotplug [ACPI] Disable memory hotplug. Useful for kdump
kernels.
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add_efi_memmap [EFI; X86] Include EFI memory map in
kernel's map of available physical RAM.
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agp= [AGP]
{ off | try_unsupported }
off: disable AGP support
try_unsupported: try to drive unsupported chipsets
(may crash computer or cause data corruption)
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ALSA [HW,ALSA]
See Documentation/sound/alsa/alsa-parameters.txt
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alignment= [KNL,ARM]
Allow the default userspace alignment fault handler
behaviour to be specified. Bit 0 enables warnings,
bit 1 enables fixups, and bit 2 sends a segfault.
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align_va_addr= [X86-64]
Align virtual addresses by clearing slice [14:12] when
allocating a VMA at process creation time. This option
gives you up to 3% performance improvement on AMD F15h
machines (where it is enabled by default) for a
CPU-intensive style benchmark, and it can vary highly in
a microbenchmark depending on workload and compiler.
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32: only for 32-bit processes
64: only for 64-bit processes
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on: enable for both 32- and 64-bit processes
off: disable for both 32- and 64-bit processes
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alloc_snapshot [FTRACE]
Allocate the ftrace snapshot buffer on boot up when the
main buffer is allocated. This is handy if debugging
and you need to use tracing_snapshot() on boot up, and
do not want to use tracing_snapshot_alloc() as it needs
to be done where GFP_KERNEL allocations are allowed.
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amd_iommu= [HW,X86-64]
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Pass parameters to the AMD IOMMU driver in the system.
Possible values are:
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fullflush - enable flushing of IO/TLB entries when
they are unmapped. Otherwise they are
flushed before they will be reused, which
is a lot of faster
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off - do not initialize any AMD IOMMU found in
the system
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force_isolation - Force device isolation for all
devices. The IOMMU driver is not
allowed anymore to lift isolation
requirements as needed. This option
does not override iommu=pt
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amd_iommu_dump= [HW,X86-64]
Enable AMD IOMMU driver option to dump the ACPI table
for AMD IOMMU. With this option enabled, AMD IOMMU
driver will print ACPI tables for AMD IOMMU during
IOMMU initialization.
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amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
Format: <a>,<b>
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See also Documentation/input/joystick.txt
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analog.map= [HW,JOY] Analog joystick and gamepad support
Specifies type or capabilities of an analog joystick
connected to one of 16 gameports
Format: <type1>,<type2>,..<type16>
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apc= [HW,SPARC]
Power management functions (SPARCstation-4/5 + deriv.)
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Format: noidle
Disable APC CPU standby support. SPARCstation-Fox does
not play well with APC CPU idle - disable it if you have
APC and your system crashes randomly.
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apic= [APIC,X86-32] Advanced Programmable Interrupt Controller
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Change the output verbosity whilst booting
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Format: { quiet (default) | verbose | debug }
Change the amount of debugging information output
when initialising the APIC and IO-APIC components.
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autoconf= [IPV6]
See Documentation/networking/ipv6.txt.
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show_lapic= [APIC,X86] Advanced Programmable Interrupt Controller
Limit apic dumping. The parameter defines the maximal
number of local apics being dumped. Also it is possible
to set it to "all" by meaning -- no limit here.
Format: { 1 (default) | 2 | ... | all }.
The parameter valid if only apic=debug or
apic=verbose is specified.
Example: apic=debug show_lapic=all
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apm= [APM] Advanced Power Management
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See header of arch/x86/kernel/apm_32.c.
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arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
Format: <io>,<irq>,<nodeID>
ataflop= [HW,M68k]
atarimouse= [HW,MOUSE] Atari Mouse
atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
EzKey and similar keyboards
atkbd.reset= [HW] Reset keyboard during initialization
2005-10-23 23:57:11 +04:00
atkbd.set= [HW] Select keyboard code set
Format: <int> (2 = AT (default), 3 = PS/2)
2005-04-17 02:20:36 +04:00
atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
keyboards
atkbd.softraw= [HW] Choose between synthetic and real raw mode
Format: <bool> (0 = real, 1 = synthetic (default))
2005-10-23 23:57:11 +04:00
atkbd.softrepeat= [HW]
Use software keyboard repeat
2005-04-17 02:20:36 +04:00
2013-09-24 05:53:35 +04:00
audit= [KNL] Enable the audit sub-system
Format: { "0" | "1" } (0 = disabled, 1 = enabled)
2014-01-14 01:01:06 +04:00
0 - kernel audit is disabled and can not be enabled
until the next reboot
unset - kernel audit is initialized but disabled and
will be fully enabled by the userspace auditd.
1 - kernel audit is initialized and partially enabled,
storing at most audit_backlog_limit messages in
RAM until it is fully enabled by the userspace
auditd.
2013-09-24 05:53:35 +04:00
Default: unset
2013-09-17 20:34:52 +04:00
2013-09-17 20:34:52 +04:00
audit_backlog_limit= [KNL] Set the audit queue size limit.
Format: <int> (must be >=0)
Default: 64
2005-04-17 02:20:36 +04:00
baycom_epp= [HW,AX25]
Format: <io>,<mode>
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
Format: <io>,<mode>
See header of drivers/net/hamradio/baycom_par.c.
2005-10-23 23:57:11 +04:00
baycom_ser_fdx= [HW,AX25]
BayCom Serial Port AX.25 Modem (Full Duplex Mode)
2005-04-17 02:20:36 +04:00
Format: <io>,<irq>,<mode>[,<baud>]
See header of drivers/net/hamradio/baycom_ser_fdx.c.
2005-10-23 23:57:11 +04:00
baycom_ser_hdx= [HW,AX25]
BayCom Serial Port AX.25 Modem (Half Duplex Mode)
2005-04-17 02:20:36 +04:00
Format: <io>,<irq>,<mode>
See header of drivers/net/hamradio/baycom_ser_hdx.c.
2013-10-01 00:45:19 +04:00
blkdevparts= Manual partition parsing of block device(s) for
embedded devices based on command line input.
See Documentation/block/cmdline-partition.txt
2007-10-16 12:23:46 +04:00
boot_delay= Milliseconds to delay each printk during boot.
Values larger than 10 seconds (10000) are changed to
no delay (0).
Format: integer
2008-08-21 01:08:58 +04:00
bootmem_debug [KNL] Enable bootmem allocator debug messages.
2005-04-17 02:20:36 +04:00
bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
2005-10-23 23:57:11 +04:00
bttv.radio= Most important insmod options are available as
kernel args too.
2005-04-17 02:20:36 +04:00
bttv.pll= See Documentation/video4linux/bttv/Insmod-options
2011-08-15 04:02:26 +04:00
bttv.tuner=
2005-04-17 02:20:36 +04:00
2010-09-28 19:33:12 +04:00
bulk_remove=off [PPC] This parameter disables the use of the pSeries
firmware feature for flushing multiple hpte entries
at a time.
2005-04-17 02:20:36 +04:00
c101= [NET] Moxa C101 synchronous serial card
2007-07-31 11:37:59 +04:00
cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
2005-04-17 02:20:36 +04:00
Sometimes CPU hardware bugs make them report the cache
size incorrectly. The kernel will attempt work arounds
to fix known problems, but for some CPUs it is not
possible to determine what the correct size should be.
This option provides an override for these situations.
2014-06-17 12:56:58 +04:00
ca_keys= [KEYS] This parameter identifies a specific key(s) on
the system trusted keyring to be used for certificate
trust validation.
2014-06-17 12:56:59 +04:00
format: { id:<keyid> | builtin }
2014-06-17 12:56:58 +04:00
2014-06-26 03:41:13 +04:00
cca= [MIPS] Override the kernel pages' cache coherency
algorithm. Accepted values range from 0 to 7
inclusive. See arch/mips/include/asm/pgtable-bits.h
for platform specific values (SB1, Loongson3 and
others).
2008-01-26 16:10:37 +03:00
ccw_timeout_log [S390]
See Documentation/s390/CommonIO for details.
2005-04-17 02:20:36 +04:00
2008-04-05 01:29:57 +04:00
cgroup_disable= [KNL] Disable a particular controller
Format: {name of the controller(s) to disable}
2013-11-07 01:18:09 +04:00
The effects of cgroup_disable=foo are:
- foo isn't auto-mounted if you mount all cgroups in
a single hierarchy
- foo isn't visible as an individually mountable
subsystem
{Currently only "memory" controller deal with this and
cut the overhead, others just disable the usage. So
only cgroup_disable=memory is actually worthy}
2008-04-05 01:29:57 +04:00
2005-04-17 02:20:36 +04:00
checkreqprot [SELINUX] Set initial checkreqprot flag value.
Format: { "0" | "1" }
See security/selinux/Kconfig help text.
2005-10-23 23:57:11 +04:00
0 -- check protection applied by kernel (includes
any implied execute protection).
2005-04-17 02:20:36 +04:00
1 -- check protection requested by application.
Default value is set via a kernel config option.
2005-10-23 23:57:11 +04:00
Value can be changed at runtime via
/selinux/checkreqprot.
2008-01-26 16:10:36 +03:00
cio_ignore= [S390]
See Documentation/s390/CommonIO for details.
2013-04-28 01:10:18 +04:00
clk_ignore_unused
[CLK]
Keep all clocks already enabled by bootloader on,
even if no driver has claimed them. This is useful
for debug and development, but should not be
needed on a platform with proper driver support.
For more information, see Documentation/clk.txt.
2008-01-26 16:10:36 +03:00
2007-07-31 11:37:59 +04:00
clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
2006-06-26 11:25:05 +04:00
[Deprecated]
2006-10-04 00:45:33 +04:00
Forces specified clocksource (if available) to be used
2006-06-26 11:25:05 +04:00
when calculating gettimeofday(). If specified
2006-10-04 00:45:33 +04:00
clocksource is not available, it defaults to PIT.
2005-04-17 02:20:36 +04:00
Format: { pit | tsc | cyclone | pmtmr }
2010-07-14 04:56:20 +04:00
clocksource= Override the default clocksource
2007-05-24 00:58:16 +04:00
Format: <string>
Override the default clocksource and use the clocksource
with the name specified.
Some clocksource names to choose from, depending on
the platform:
[all] jiffies (this is the base, fallback clocksource)
[ACPI] acpi_pm
[ARM] imx_timer1,OSTS,netx_timer,mpu_timer2,
pxa_timer,timer3,32k_counter,timer0_1
[AVR32] avr32
2010-08-24 01:49:11 +04:00
[X86-32] pit,hpet,tsc;
2007-05-24 00:58:16 +04:00
scx200_hrt on Geode; cyclone on IBM x440
[MIPS] MIPS
[PARISC] cr16
[S390] tod
[SH] SuperH
[SPARC64] tick
[X86-64] hpet,tsc
2008-01-30 15:33:21 +03:00
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
2009-01-07 01:42:41 +03:00
arch/x86/include/asm/cpufeature.h for the valid bit
numbers. Note the Linux specific bits are not necessarily
2008-01-30 15:33:21 +03:00
stable over kernel options, but the vendor specific
ones should be.
Also note that user programs calling CPUID directly
or using the feature without checking anything
will still see it. This just prevents it from
being used by the kernel or shown in /proc/cpuinfo.
Also note the kernel might malfunction if you disable
some critical bits.
2014-06-05 03:06:54 +04:00
cma=nn[MG]@[start[MG][-end[MG]]]
[ARM,X86,KNL]
Sets the size of kernel global memory area for
contiguous memory allocations and optionally the
placement constraint by the physical address range of
2011-12-29 16:09:51 +04:00
memory allocations. For more information, see
include/linux/dma-contiguous.h
2009-04-15 09:55:32 +04:00
cmo_free_hint= [PPC] Format: { yes | no }
Specify whether pages are marked as being inactive
when they are freed. This is used in CMO environments
to determine OS memory pressure for page stealing by
a hypervisor.
Default: yes
2011-12-29 16:09:51 +04:00
coherent_pool=nn[KMG] [ARM,KNL]
Sets the size of memory pool for coherent, atomic dma
2012-07-30 11:11:33 +04:00
allocations, by default set to 256K.
2011-12-29 16:09:51 +04:00
2009-04-14 12:33:43 +04:00
code_bytes [X86] How many bytes of object code to print
2008-01-30 15:33:08 +03:00
in an oops report.
2007-02-13 15:26:25 +03:00
Range: 0 - 8192
Default: 64
2005-04-17 02:20:36 +04:00
com20020= [HW,NET] ARCnet - COM20020 chipset
2005-10-23 23:57:11 +04:00
Format:
<io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
2005-04-17 02:20:36 +04:00
com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
Format: <io>[,<irq>]
2005-10-23 23:57:11 +04:00
com90xx= [HW,NET]
ARCnet - COM90xx chipset (memory-mapped buffers)
2005-04-17 02:20:36 +04:00
Format: <io>[,<irq>[,<memstart>]]
condev= [HW,S390] console device
conmode=
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
console= [KNL] Output console device and options.
tty<n> Use the virtual console device <n>.
ttyS<n>[,options]
2006-03-25 14:08:17 +03:00
ttyUSB0[,options]
2005-04-17 02:20:36 +04:00
Use the specified serial port. The options are of
2006-03-25 14:08:17 +03:00
the form "bbbbpnf", where "bbbb" is the baud rate,
"p" is parity ("n", "o", or "e"), "n" is number of
bits, and "f" is flow control ("r" for RTS or
omit it). Default is "9600n8".
See Documentation/serial-console.txt for more
information. See
Documentation/networking/netconsole.txt for an
alternative.
2005-04-17 02:20:36 +04:00
serial: convert early_uart to earlycon for 8250
Beacuse SERIAL_PORT_DFNS is removed from include/asm-i386/serial.h and
include/asm-x86_64/serial.h. the serial8250_ports need to be probed late in
serial initializing stage. the console_init=>serial8250_console_init=>
register_console=>serial8250_console_setup will return -ENDEV, and console
ttyS0 can not be enabled at that time. need to wait till uart_add_one_port in
drivers/serial/serial_core.c to call register_console to get console ttyS0.
that is too late.
Make early_uart to use early_param, so uart console can be used earlier. Make
it to be bootconsole with CON_BOOT flag, so can use console handover feature.
and it will switch to corresponding normal serial console automatically.
new command line will be:
console=uart8250,io,0x3f8,9600n8
console=uart8250,mmio,0xff5e0000,115200n8
or
earlycon=uart8250,io,0x3f8,9600n8
earlycon=uart8250,mmio,0xff5e0000,115200n8
it will print in very early stage:
Early serial console at I/O port 0x3f8 (options '9600n8')
console [uart0] enabled
later for console it will print:
console handover: boot [uart0] -> real [ttyS0]
Signed-off-by: <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 10:37:59 +04:00
uart[8250],io,<addr>[,options]
uart[8250],mmio,<addr>[,options]
2005-04-17 02:20:36 +04:00
Start an early, polled-mode console on the 8250/16550
UART at the specified I/O port or MMIO address,
switching to the matching ttyS device later. The
options are the same as for ttyS, above.
2013-02-26 00:54:09 +04:00
hvc<n> Use the hypervisor console device <n>. This is for
both Xen and PowerPC hypervisors.
2005-04-17 02:20:36 +04:00
2008-04-30 11:54:51 +04:00
If the device connected to the port is not a TTY but a braille
device, prepend "brl," before the device type, for instance
console=brl,ttyS0
For now, only VisioBraille is supported.
2009-06-17 02:33:52 +04:00
consoleblank= [KNL] The console blank (screen saver) timeout in
seconds. Defaults to 10*60 = 10mins. A value of 0
disables the blank timer.
2009-01-07 01:42:47 +03:00
coredump_filter=
[KNL] Change the default value for
/proc/<pid>/coredump_filter.
See also Documentation/filesystems/proc.txt.
2011-04-02 02:13:10 +04:00
cpuidle.off=1 [CPU_IDLE]
disable the cpuidle sub-system
2005-04-17 02:20:36 +04:00
cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
2005-10-23 23:57:11 +04:00
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
2005-04-17 02:20:36 +04:00
2011-02-21 07:08:35 +03:00
crashkernel=size[KMG][@offset[KMG]]
[KNL] Using kexec, Linux can switch to a 'crash kernel'
upon panic. This parameter reserves the physical
memory region [offset, offset + size] for that kernel
image. If '@offset' is omitted, then a suitable offset
is selected automatically. Check
Documentation/kdump/kdump.txt for further details.
2005-06-26 01:57:52 +04:00
2007-10-19 10:41:02 +04:00
crashkernel=range1:size1[,range2:size2,...][@offset]
[KNL] Same as above, but depends on the memory
in the running system. The syntax of range is
start-[end] where start and end are both
a memory unit (amount[KMG]). See also
2011-02-21 07:08:35 +03:00
Documentation/kdump/kdump.txt for an example.
2007-10-19 10:41:02 +04:00
x86, kdump: Change crashkernel_high/low= to crashkernel=,high/low
Per hpa, use crashkernel=X,high crashkernel=Y,low instead of
crashkernel_hign=X crashkernel_low=Y. As that could be extensible.
-v2: according to Vivek, change delimiter to ;
-v3: let hign and low only handle simple form and it conforms to
description in kernel-parameters.txt
still keep crashkernel=X override any crashkernel=X,high
crashkernel=Y,low
-v4: update get_last_crashkernel returning and add more strict
checking in parse_crashkernel_simple() found by HATAYAMA.
-v5: Change delimiter back to , according to HPA.
also separate parse_suffix from parse_simper according to vivek.
so we can avoid @pos in that path.
-v6: Tight the checking about crashkernel=X,highblahblah,high
found by HTYAYAMA.
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1366089828-19692-5-git-send-email-yinghai@kernel.org
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-16 09:23:48 +04:00
crashkernel=size[KMG],high
2013-04-16 09:23:47 +04:00
[KNL, x86_64] range could be above 4G. Allow kernel
to allocate physical memory region from top, so could
be above 4G if system have more than 4G ram installed.
Otherwise memory region will be allocated below 4G, if
available.
It will be ignored if crashkernel=X is specified.
x86, kdump: Change crashkernel_high/low= to crashkernel=,high/low
Per hpa, use crashkernel=X,high crashkernel=Y,low instead of
crashkernel_hign=X crashkernel_low=Y. As that could be extensible.
-v2: according to Vivek, change delimiter to ;
-v3: let hign and low only handle simple form and it conforms to
description in kernel-parameters.txt
still keep crashkernel=X override any crashkernel=X,high
crashkernel=Y,low
-v4: update get_last_crashkernel returning and add more strict
checking in parse_crashkernel_simple() found by HATAYAMA.
-v5: Change delimiter back to , according to HPA.
also separate parse_suffix from parse_simper according to vivek.
so we can avoid @pos in that path.
-v6: Tight the checking about crashkernel=X,highblahblah,high
found by HTYAYAMA.
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1366089828-19692-5-git-send-email-yinghai@kernel.org
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-16 09:23:48 +04:00
crashkernel=size[KMG],low
[KNL, x86_64] range under 4G. When crashkernel=X,high
is passed, kernel could allocate physical memory region
2013-04-16 09:23:45 +04:00
above 4G, that cause second kernel crash on system
that require some amount of low memory, e.g. swiotlb
requires at least 64M+32K low memory. Kernel would
try to allocate 72M below 4G automatically.
This one let user to specify own low range under 4G
for second kernel instead.
0: to disable low allocation.
x86, kdump: Change crashkernel_high/low= to crashkernel=,high/low
Per hpa, use crashkernel=X,high crashkernel=Y,low instead of
crashkernel_hign=X crashkernel_low=Y. As that could be extensible.
-v2: according to Vivek, change delimiter to ;
-v3: let hign and low only handle simple form and it conforms to
description in kernel-parameters.txt
still keep crashkernel=X override any crashkernel=X,high
crashkernel=Y,low
-v4: update get_last_crashkernel returning and add more strict
checking in parse_crashkernel_simple() found by HATAYAMA.
-v5: Change delimiter back to , according to HPA.
also separate parse_suffix from parse_simper according to vivek.
so we can avoid @pos in that path.
-v6: Tight the checking about crashkernel=X,highblahblah,high
found by HTYAYAMA.
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1366089828-19692-5-git-send-email-yinghai@kernel.org
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-16 09:23:48 +04:00
It will be ignored when crashkernel=X,high is not used
2013-04-16 09:23:47 +04:00
or memory reserved is below 4G.
2013-04-16 09:23:45 +04:00
2005-04-17 02:20:36 +04:00
cs89x0_dma= [HW,NET]
Format: <dma>
cs89x0_media= [HW,NET]
Format: { rj45 | aui | bnc }
2005-10-23 23:57:11 +04:00
dasd= [HW,NET]
2005-04-17 02:20:36 +04:00
See header of drivers/s390/block/dasd_devmap.c.
db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
(one device per port)
Format: <port#>,<type>
See also Documentation/input/joystick-parport.txt
2010-08-06 18:11:02 +04:00
ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot
time. See Documentation/dynamic-debug-howto.txt for
2012-04-28 00:30:41 +04:00
details. Deprecated, see dyndbg.
2010-08-06 18:11:02 +04:00
2005-04-17 02:20:36 +04:00
debug [KNL] Enable kernel debugging (events log level).
2006-07-03 11:24:48 +04:00
debug_locks_verbose=
[KNL] verbose self-tests
Format=<0|1>
Print debugging info while doing the locking API
self-tests.
We default to 0 (no extra messages), setting it to
1 will print _a lot_ more information - normally
only useful to kernel developers.
2008-04-30 11:55:01 +04:00
debug_objects [KNL] Enable object debugging
2009-03-02 04:41:41 +03:00
no_debug_objects
[KNL] Disable object debugging
2012-01-11 03:07:28 +04:00
debug_guardpage_minorder=
[KNL] When CONFIG_DEBUG_PAGEALLOC is set, this
parameter allows control of the order of pages that will
be intentionally kept free (and hence protected) by the
buddy allocator. Bigger value increase the probability
of catching random memory corruption, but reduce the
amount of memory for normal system use. The maximum
possible value is MAX_ORDER/2. Setting this parameter
to 1 or 2 should be enough to identify most random
memory corruption problems caused by bugs in kernel or
driver code when a CPU writes to (or reads from) a
random memory location. Note that there exists a class
of memory corruptions problems caused by buggy H/W or
F/W or by drivers badly programing DMA (basically when
memory is written at bus level and the CPU MMU is
bypassed) which are not detectable by
CONFIG_DEBUG_PAGEALLOC, hence this option will not help
tracking down these problems.
2008-07-15 17:04:56 +04:00
debugpat [X86] Enable PAT debugging
2008-02-03 16:18:45 +03:00
decnet.addr= [HW,NET]
2005-04-17 02:20:36 +04:00
Format: <area>[,<node>]
See also Documentation/networking/decnet.txt.
2009-04-06 02:55:22 +04:00
default_hugepagesz=
[same as hugepagesz=] The size of the default
HugeTLB page size. This is the size represented by
the legacy /proc/ hugepages APIs, used for SHM, and
default size when mounting hugetlbfs filesystems.
Defaults to the default architecture's huge page size
if not specified.
2007-05-08 11:38:53 +04:00
2005-04-17 02:20:36 +04:00
dhash_entries= [KNL]
Set number of hash buckets for dentry cache.
2005-10-23 23:57:11 +04:00
2010-02-05 00:36:50 +03:00
disable= [IPV6]
See Documentation/networking/ipv6.txt.
x86, apic, kexec: Add disable_cpu_apicid kernel parameter
Add disable_cpu_apicid kernel parameter. To use this kernel parameter,
specify an initial APIC ID of the corresponding CPU you want to
disable.
This is mostly used for the kdump 2nd kernel to disable BSP to wake up
multiple CPUs without causing system reset or hang due to sending INIT
from AP to BSP.
Kdump users first figure out initial APIC ID of the BSP, CPU0 in the
1st kernel, for example from /proc/cpuinfo and then set up this kernel
parameter for the 2nd kernel using the obtained APIC ID.
However, doing this procedure at each boot time manually is awkward,
which should be automatically done by user-land service scripts, for
example, kexec-tools on fedora/RHEL distributions.
This design is more flexible than disabling BSP in kernel boot time
automatically in that in kernel boot time we have no choice but
referring to ACPI/MP table to obtain initial APIC ID for BSP, meaning
that the method is not applicable to the systems without such BIOS
tables.
One assumption behind this design is that users get initial APIC ID of
the BSP in still healthy state and so BSP is uniquely kept in
CPU0. Thus, through the kernel parameter, only one initial APIC ID can
be specified.
In a comparison with disabled_cpu_apicid, we use read_apic_id(), not
boot_cpu_physical_apicid, because on some platforms, the variable is
modified to the apicid reported as BSP through MP table and this
function is executed with the temporarily modified
boot_cpu_physical_apicid. As a result, disabled_cpu_apicid kernel
parameter doesn't work well for apicids of APs.
Fixing the wrong handling of boot_cpu_physical_apicid requires some
reviews and tests beyond some platforms and it could take some
time. The fix here is a kind of workaround to focus on the main topic
of this patch.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/20140115064458.1545.38775.stgit@localhost6.localdomain6
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-01-15 10:44:58 +04:00
disable_cpu_apicid= [X86,APIC,SMP]
Format: <int>
The number of initial APIC ID for the
corresponding CPU to be disabled at boot,
mostly used for the kdump 2nd kernel to
disable BSP to wake up multiple CPUs without
causing system reset or hang due to sending
INIT from AP to BSP.
2011-02-10 12:10:47 +03:00
disable_ddw [PPC/PSERIES]
Disable Dynamic DMA Window support. Use this if
to workaround buggy firmware.
2010-02-05 00:36:50 +03:00
disable_ipv6= [IPV6]
See Documentation/networking/ipv6.txt.
2008-04-29 14:52:33 +04:00
disable_mtrr_cleanup [X86]
The kernel tries to adjust MTRR layout from continuous
to discrete, to make X server driver able to add WB
2009-04-06 02:55:22 +04:00
entry later. This parameter disables that.
2008-04-29 14:52:33 +04:00
2008-01-30 15:33:32 +03:00
disable_mtrr_trim [X86, Intel and AMD only]
x86, 32-bit: trim memory not covered by wb mtrrs
On some machines, buggy BIOSes don't properly setup WB MTRRs to cover all
available RAM, meaning the last few megs (or even gigs) of memory will be
marked uncached. Since Linux tends to allocate from high memory addresses
first, this causes the machine to be unusably slow as soon as the kernel
starts really using memory (i.e. right around init time).
This patch works around the problem by scanning the MTRRs at boot and
figuring out whether the current end_pfn value (setup by early e820 code)
goes beyond the highest WB MTRR range, and if so, trimming it to match. A
fairly obnoxious KERN_WARNING is printed too, letting the user know that
not all of their memory is available due to a likely BIOS bug.
Something similar could be done on i386 if needed, but the boot ordering
would be slightly different, since the MTRR code on i386 depends on the
boot_cpu_data structure being setup.
This patch fixes a bug in the last patch that caused the code to run on
non-Intel machines (AMD machines apparently don't need it and it's untested
on other non-Intel machines, so best keep it off).
Further enhancements and fixes from:
Yinghai Lu <Yinghai.Lu@Sun.COM>
Andi Kleen <ak@suse.de>
Signed-off-by: Jesse Barnes <jesse.barnes@intel.com>
Tested-by: Justin Piszcz <jpiszcz@lucidpixels.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 15:33:18 +03:00
By default the kernel will trim any uncacheable
memory out of your available memory pool based on
MTRR settings. This parameter disables that behavior,
possibly causing your machine to run very slowly.
2009-04-14 12:33:43 +04:00
disable_timer_pin_1 [X86]
2009-04-06 02:55:22 +04:00
Disable PIN 1 of APIC timer
Can be useful to work around chipset bugs.
dma_debug=off If the kernel is compiled with DMA_API_DEBUG support,
this option disables the debugging code at boot.
dma_debug_entries=<number>
This option allows to tune the number of preallocated
entries for DMA-API debugging code. One entry is
required per DMA-API allocation. Use this if the
DMA-API debugging code disables itself because the
architectural default is too low.
2009-05-22 23:49:51 +04:00
dma_debug_driver=<driver_name>
With this option the DMA-API debugging driver
filter feature can be enabled at boot time. Just
pass the driver to filter for as the parameter.
The filter can be disabled or changed to another
driver later using sysfs.
2012-03-19 01:37:33 +04:00
drm_kms_helper.edid_firmware=[<connector>:]<file>
Broken monitors, graphic adapters and KVMs may
send no or incorrect EDID data sets. This parameter
allows to specify an EDID data set in the
/lib/firmware directory that is used instead.
Generic built-in EDID data sets are used, if one of
edid/1024x768.bin, edid/1280x1024.bin,
edid/1680x1050.bin, or edid/1920x1080.bin is given
and no file with the same name exists. Details and
instructions how to build your own EDID data are
available in Documentation/EDID/HOWTO.txt. An EDID
data set will only be used for a particular connector,
if its name and a colon are prepended to the EDID
name.
2005-04-17 02:20:36 +04:00
dscc4.setup= [NET]
2012-04-28 00:30:41 +04:00
dyndbg[="val"] [KNL,DYNAMIC_DEBUG]
module.dyndbg[="val"]
Enable debug messages at boot time. See
Documentation/dynamic-debug-howto.txt for details.
2014-04-08 02:39:53 +04:00
early_ioremap_debug [KNL]
Enable debug messages in early_ioremap support. This
is useful for tracking down temporary early mappings
which are not unmapped.
2009-04-06 02:55:22 +04:00
earlycon= [KNL] Output early console device and options.
2014-04-19 02:19:57 +04:00
2009-04-06 02:55:22 +04:00
uart[8250],io,<addr>[,options]
uart[8250],mmio,<addr>[,options]
2010-07-21 02:26:51 +04:00
uart[8250],mmio32,<addr>[,options]
2009-04-06 02:55:22 +04:00
Start an early, polled-mode console on the 8250/16550
UART at the specified I/O port or MMIO address.
2011-08-13 23:34:52 +04:00
MMIO inter-register address stride is either 8-bit
(mmio) or 32-bit (mmio32).
2009-04-06 02:55:22 +04:00
The options are the same as for ttyS, above.
2014-04-19 02:19:57 +04:00
pl011,<addr>
Start an early, polled-mode console on a pl011 serial
port at the specified address. The pl011 serial port
must already be setup and configured. Options are not
yet supported.
2014-04-19 02:19:58 +04:00
smh Use ARM semihosting calls for early console.
2014-04-12 17:48:56 +04:00
earlyprintk= [X86,SH,BLACKFIN,ARM,M68k]
2005-04-17 02:20:36 +04:00
earlyprintk=vga
2013-10-04 12:36:56 +04:00
earlyprintk=efi
2013-02-26 00:54:08 +04:00
earlyprintk=xen
2005-04-17 02:20:36 +04:00
earlyprintk=serial[,ttySn[,baudrate]]
2013-04-11 01:03:38 +04:00
earlyprintk=serial[,0x...[,baudrate]]
2009-09-24 18:08:30 +04:00
earlyprintk=ttySn[,baudrate]
2009-08-21 00:39:57 +04:00
earlyprintk=dbgp[debugController#]
2005-04-17 02:20:36 +04:00
2013-04-11 01:03:38 +04:00
earlyprintk is useful when the kernel crashes before
the normal console is initialized. It is not enabled by
default because it has some cosmetic problems.
2005-10-23 23:57:11 +04:00
Append ",keep" to not disable it when the real console
2005-04-17 02:20:36 +04:00
takes over.
2013-10-04 12:36:56 +04:00
Only one of vga, efi, serial, or usb debug port can
be used at a time.
2005-04-17 02:20:36 +04:00
2013-04-11 01:03:38 +04:00
Currently only ttyS0 and ttyS1 may be specified by
name. Other I/O ports may be explicitly specified
on some architectures (x86 and arm at least) by
replacing ttySn with an I/O port address, like this:
earlyprintk=serial,0x1008,115200
You can find the port for a given device in
/proc/tty/driver/serial:
2: uart:ST16650V2 port:00001008 irq:18 ...
2005-04-17 02:20:36 +04:00
Interaction with the standard serial driver is not
very good.
2013-10-04 12:36:56 +04:00
The VGA and EFI output is eventually overwritten by
the real console.
2005-04-17 02:20:36 +04:00
2013-02-26 00:54:08 +04:00
The xen output can only be used by Xen PV guests.
2013-12-06 10:17:08 +04:00
edac_report= [HW,EDAC] Control how to report EDAC event
Format: {"on" | "off" | "force"}
on: enable EDAC to report H/W event. May be overridden
by other higher priority error reporting module.
off: disable H/W event reporting through EDAC.
force: enforce the use of EDAC to report H/W event.
default: on.
2010-05-21 06:04:30 +04:00
ekgdboc= [X86,KGDB] Allow early kernel console debugging
ekgdboc=kbd
2011-03-31 05:57:33 +04:00
This is designed to be used in conjunction with
2010-05-21 06:04:30 +04:00
the boot argument: earlyprintk=vga
2005-04-17 02:20:36 +04:00
edd= [EDD]
2008-04-29 12:02:45 +04:00
Format: {"off" | "on" | "skip[mbr]"}
2005-04-17 02:20:36 +04:00
2013-10-31 20:25:08 +04:00
efi= [EFI]
Format: { "old_map" }
old_map [X86-64]: switch to the old ioremap-based EFI
runtime services mapping. 32-bit still uses this one by
default.
2013-04-17 03:00:53 +04:00
efi_no_storage_paranoia [EFI; X86]
Using this parameter you can use more than 50% of
your efi variable storage. Use this parameter only if
you are really sure that your UEFI does sane gc and
fulfills the spec otherwise your board may brick.
2005-04-17 02:20:36 +04:00
eisa_irq_edge= [PARISC,HW]
See header of drivers/parisc/eisa.c.
2007-07-31 11:37:59 +04:00
elanfreq= [X86-32]
2005-04-17 02:20:36 +04:00
See comment before function elanfreq_setup() in
2008-07-04 20:59:43 +04:00
arch/x86/kernel/cpu/cpufreq/elanfreq.c.
2005-04-17 02:20:36 +04:00
elevator= [IOSCHED]
2010-11-11 14:09:59 +03:00
Format: {"cfq" | "deadline" | "noop"}
2011-08-15 04:02:26 +04:00
See Documentation/block/cfq-iosched.txt and
2005-10-23 23:57:11 +04:00
Documentation/block/deadline-iosched.txt for details.
2011-10-30 18:16:37 +04:00
elfcorehdr=[size[KMG]@]offset[KMG] [IA64,PPC,SH,X86,S390]
2005-10-23 23:57:11 +04:00
Specifies physical address of start of kernel core
2011-10-30 18:16:37 +04:00
image elf header and optionally the size. Generally
kexec loader will pass this option to capture kernel.
2006-01-10 07:51:47 +03:00
See Documentation/kdump/kdump.txt for details.
2005-04-17 02:20:36 +04:00
2009-04-06 02:55:22 +04:00
enable_mtrr_cleanup [X86]
The kernel tries to adjust MTRR layout from continuous
to discrete, to make X server driver able to add WB
entry later. This parameter enables that.
2009-05-07 03:02:58 +04:00
enable_timer_pin_1 [X86]
2009-04-06 02:55:22 +04:00
Enable PIN 1 of APIC timer
Can be useful to work around chipset bugs
(in particular on some ATI chipsets).
The kernel tries to set a reasonable default.
2005-04-17 02:20:36 +04:00
enforcing [SELINUX] Set initial enforcing status.
Format: {"0" | "1"}
See security/selinux/Kconfig help text.
0 -- permissive (log only, no denials).
1 -- enforcing (deny and log).
Default value is 0.
Value can be changed at runtime via /selinux/enforce.
2010-05-18 10:35:21 +04:00
erst_disable [ACPI]
Disable Error Record Serialization Table (ERST)
support.
2005-04-17 02:20:36 +04:00
ether= [HW,NET] Ethernet cards parameters
This option is obsoleted by the "netdev=" option, which
has equivalent usage. See its documentation for details.
2011-05-13 02:33:20 +04:00
evm= [EVM]
Format: { "fix" }
Permit 'security.evm' to be updated regardless of
current integrity status.
2006-12-08 13:39:42 +03:00
failslab=
fail_page_alloc=
fail_make_request=[KNL]
General fault injection mechanism.
Format: <interval>,<probability>,<space>,<times>
2011-08-15 04:02:26 +04:00
See also Documentation/fault-injection/.
2006-12-08 13:39:42 +03:00
2005-04-17 02:20:36 +04:00
floppy= [HW]
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/floppy.txt.
2005-04-17 02:20:36 +04:00
2008-05-09 00:03:23 +04:00
force_pal_cache_flush
[IA-64] Avoid check_sal_cache_flush which may hang on
buggy SAL_CACHE_FLUSH implementations. Using this
parameter will force ia64_sal_cache_flush to call
ia64_pal_cache_flush instead of SAL_CACHE_FLUSH.
2014-03-07 15:40:42 +04:00
forcepae [X86-32]
Forcefully enable Physical Address Extension (PAE).
Many Pentium M systems disable PAE but may have a
functionally usable PAE implementation.
Warning: use of this parameter will taint the kernel
and may cause unknown problems.
2008-11-01 21:57:37 +03:00
ftrace=[tracer]
2009-05-28 21:37:24 +04:00
[FTRACE] will set and start the specified tracer
2008-11-01 21:57:37 +03:00
as early as possible in order to facilitate early
boot debugging.
2010-04-18 21:08:41 +04:00
ftrace_dump_on_oops[=orig_cpu]
2009-05-28 21:37:24 +04:00
[FTRACE] will dump the trace buffers on oops.
2010-04-18 21:08:41 +04:00
If no parameter is passed, ftrace will dump
buffers of all CPUs, but if you pass orig_cpu, it will
dump only the buffer of the CPU that triggered the
oops.
2009-05-28 21:37:24 +04:00
ftrace_filter=[function-list]
[FTRACE] Limit the functions traced by the function
tracer at boot up. function-list is a comma separated
list of functions. This list can be changed at run
time by the set_ftrace_filter file in the debugfs
2011-08-13 23:34:52 +04:00
tracing directory.
2009-05-28 21:37:24 +04:00
ftrace_notrace=[function-list]
[FTRACE] Do not trace the functions specified in
function-list. This list can be changed at run time
by the set_ftrace_notrace file in the debugfs
tracing directory.
2008-11-01 21:57:37 +03:00
2009-10-13 00:17:21 +04:00
ftrace_graph_filter=[function-list]
[FTRACE] Limit the top level callers functions traced
by the function graph tracer at boot up.
function-list is a comma separated list of functions
that can be changed at run time by the
set_graph_function file in the debugfs tracing directory.
2014-06-12 20:23:50 +04:00
ftrace_graph_notrace=[function-list]
[FTRACE] Do not trace from the functions specified in
function-list. This list is a comma separated list of
functions that can be changed at run time by the
set_graph_notrace file in the debugfs tracing directory.
2005-04-17 02:20:36 +04:00
gamecon.map[2|3]=
[HW,JOY] Multisystem joystick and NES/SNES/PSX pad
support via parallel port (up to 5 devices per port)
Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
See also Documentation/input/joystick-parport.txt
gamma= [HW,DRM]
x86: disable the GART early, 64-bit
For K8 system: 4G RAM with memory hole remapping enabled, or more than
4G RAM installed.
when try to use kexec second kernel, and the first doesn't include
gart_shutdown. the second kernel could have different aper position than
the first kernel. and second kernel could use that hole as RAM that is
still used by GART set by the first kernel. esp. when try to kexec
2.6.24 with sparse mem enable from previous kernel (from RHEL 5 or SLES
10). the new kernel will use aper by GART (set by first kernel) for
vmemmap. and after new kernel setting one new GART. the position will be
real RAM. the _mapcount set is lost.
Bad page state in process 'swapper'
page:ffffe2000e600020 flags:0x0000000000000000 mapping:0000000000000000 mapcount:1 count:0
Trying to fix it up, but a reboot is needed
Backtrace:
Pid: 0, comm: swapper Not tainted 2.6.24-rc7-smp-gcdf71a10-dirty #13
Call Trace:
[<ffffffff8026401f>] bad_page+0x63/0x8d
[<ffffffff80264169>] __free_pages_ok+0x7c/0x2a5
[<ffffffff80ba75d1>] free_all_bootmem_core+0xd0/0x198
[<ffffffff80ba3a42>] numa_free_all_bootmem+0x3b/0x76
[<ffffffff80ba3461>] mem_init+0x3b/0x152
[<ffffffff80b959d3>] start_kernel+0x236/0x2c2
[<ffffffff80b9511a>] _sinittext+0x11a/0x121
and
[ffffe2000e600000-ffffe2000e7fffff] PMD ->ffff81001c200000 on node 0
phys addr is : 0x1c200000
RHEL 5.1 kernel -53 said:
PCI-DMA: aperture base @ 1c000000 size 65536 KB
new kernel said:
Mapping aperture over 65536 KB of RAM @ 3c000000
So could try to disable that GART if possible.
According to Ingo
> hm, i'm wondering, instead of modifying the GART, why dont we simply
> _detect_ whatever GART settings we have inherited, and propagate that
> into our e820 maps? I.e. if there's inconsistency, then punch that out
> from the memory maps and just dont use that memory.
>
> that way it would not matter whether the GART settings came from a [old
> or crashing] Linux kernel that has not called gart_iommu_shutdown(), or
> whether it's a BIOS that has set up an aperture hole inconsistent with
> the memory map it passed. (or the memory map we _think_ i tried to pass
> us)
>
> it would also be more robust to only read and do a memory map quirk
> based on that, than actively trying to change the GART so early in the
> bootup. Later on we have to re-enable the GART _anyway_ and have to
> punch a hole for it.
>
> and as a bonus, we would have shored up our defenses against crappy
> BIOSes as well.
add e820 modification for gart inconsistent setting.
gart_fix_e820=off could be used to disable e820 fix.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 15:33:09 +03:00
gart_fix_e820= [X86_64] disable the fix e820 for K8 GART
Format: off | on
default: on
2009-06-18 03:28:08 +04:00
gcov_persist= [GCOV] When non-zero (default), profiling data for
kernel modules is saved and remains accessible via
debugfs, even when the module is unloaded/reloaded.
When zero, profiling data is discarded and associated
debugfs files are removed at module unload time.
2005-04-17 02:20:36 +04:00
gpt [EFI] Forces disk with valid GPT signature but
2014-01-24 03:56:03 +04:00
invalid Protective MBR to be treated as GPT. If the
primary GPT is corrupted, it enables the backup/alternate
GPT to be used instead.
2005-04-17 02:20:36 +04:00
2012-11-15 11:47:14 +04:00
grcan.enable0= [HW] Configuration of physical interface 0. Determines
the "Enable 0" bit of the configuration register.
Format: 0 | 1
Default: 0
grcan.enable1= [HW] Configuration of physical interface 1. Determines
the "Enable 0" bit of the configuration register.
Format: 0 | 1
Default: 0
grcan.select= [HW] Select which physical interface to use.
Format: 0 | 1
Default: 0
grcan.txsize= [HW] Sets the size of the tx buffer.
Format: <unsigned int> such that (txsize & ~0x1fffc0) == 0.
Default: 1024
grcan.rxsize= [HW] Sets the size of the rx buffer.
Format: <unsigned int> such that (rxsize & ~0x1fffc0) == 0.
Default: 1024
2005-04-17 02:20:36 +04:00
hashdist= [KNL,NUMA] Large hashes allocated during boot
are distributed across NUMA nodes. Defaults on
2011-08-13 23:34:52 +04:00
for 64-bit NUMA, off otherwise.
2005-10-23 23:57:11 +04:00
Format: 0 | 1 (for off | on)
2005-04-17 02:20:36 +04:00
hcl= [IA-64] SGI's Hardware Graph compatibility layer
hd= [EIDE] (E)IDE hard drive subsystem geometry
Format: <cyl>,<head>,<sect>
2010-05-18 10:35:15 +04:00
hest_disable [ACPI]
Disable Hardware Error Source Table (HEST) support;
corresponding firmware-first mode error processing
logic will be disabled.
2005-04-17 02:20:36 +04:00
highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
size of <nn>. This works even on boxes that have no
highmem otherwise. This also works to reduce highmem
size on bigger boxes.
2007-02-16 12:28:11 +03:00
highres= [KNL] Enable/disable high resolution timer mode.
Valid parameters: "on", "off"
Default: "on"
2005-04-17 02:20:36 +04:00
hisax= [HW,ISDN]
See Documentation/isdn/README.HiSax.
2009-04-06 02:55:22 +04:00
hlt [BUGS=ARM,SH]
hpet= [X86-32,HPET] option to control HPET usage
Format: { enable (default) | disable | force |
verbose }
disable: disable HPET and use PIT instead
force: allow force enabled of undocumented chips (ICH4,
VIA, nVidia)
verbose: show contents of HPET registers during setup
2013-11-13 03:08:33 +04:00
hpet_mmap= [X86, HPET_MMAP] Allow userspace to mmap HPET
registers. Default set by CONFIG_HPET_MMAP_DEFAULT.
2008-07-24 08:27:51 +04:00
hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
2008-07-24 08:27:56 +04:00
On x86-64 and powerpc, this option can be specified
multiple times interleaved with hugepages= to reserve
huge pages of different sizes. Valid pages sizes on
x86-64 are 2M (when the CPU supports "pse") and 1G
(when the CPU supports the "pdpe1gb" cpuinfo flag)
2008-07-24 08:27:51 +04:00
Note that 1GB pages can only be allocated at boot time
using hugepages= and not freed afterwards.
2008-09-21 12:14:42 +04:00
2009-01-09 14:15:02 +03:00
hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC)
terminal devices. Valid values: 0..8
2009-03-26 17:23:55 +03:00
hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
If specified, z/VM IUCV HVC accepts connections
from listed z/VM user IDs only.
2008-12-25 15:39:55 +03:00
2012-10-09 14:00:27 +04:00
hwthread_map= [METAG] Comma-separated list of Linux cpu id to
hardware thread id mappings.
Format: <cpu>:<hwthread>
2011-03-23 02:34:20 +03:00
keep_bootcon [KNL]
Do not unregister boot console at start. This is only
useful for debugging when something happens in the window
between unregistering the boot console and initializing
the real console.
2009-03-24 04:07:47 +03:00
i2c_bus= [HW] Override the default board specific I2C bus speed
2009-03-24 04:07:48 +03:00
or register an additional I2C bus that is not
registered from board initialization code.
2009-03-24 04:07:47 +03:00
Format:
<bus_id>,<clkrate>
2008-10-06 10:51:09 +04:00
i8042.debug [HW] Toggle i8042 debug mode
2005-04-17 02:20:36 +04:00
i8042.direct [HW] Put keyboard port into non-translated mode
2006-10-04 00:53:09 +04:00
i8042.dumbkbd [HW] Pretend that controller can only read data from
keyboard and cannot control its state
2005-04-17 02:20:36 +04:00
(Don't attempt to blink the leds)
i8042.noaux [HW] Don't check for auxiliary (== mouse) port
2005-09-04 10:42:00 +04:00
i8042.nokbd [HW] Don't check/create keyboard port
2008-03-13 23:13:59 +03:00
i8042.noloop [HW] Disable the AUX Loopback command while probing
for the AUX port
2005-04-17 02:20:36 +04:00
i8042.nomux [HW] Don't check presence of an active multiplexing
controller
i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
controllers
2012-02-14 19:26:42 +04:00
i8042.notimeout [HW] Ignore timeout condition signalled by controller
2005-04-17 02:20:36 +04:00
i8042.reset [HW] Reset the controller during init and cleanup
i8042.unlock [HW] Unlock (ignore) the keylock
i810= [HW,DRM]
2005-06-26 01:54:25 +04:00
i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
indicates that the driver is running on unsupported
hardware.
2005-04-17 02:20:36 +04:00
i8k.force [HW] Activate i8k driver even if SMM BIOS signature
does not match list of supported models.
i8k.power_status
[HW] Report power status in /proc/i8k
(disabled by default)
i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
capability is set.
2012-03-15 18:56:26 +04:00
i915.invert_brightness=
2012-03-15 18:56:25 +04:00
[DRM] Invert the sense of the variable that is used to
set the brightness of the panel backlight. Normally a
2012-03-15 18:56:26 +04:00
brightness value of 0 indicates backlight switched off,
and the maximum of the brightness value sets the backlight
to maximum brightness. If this parameter is set to 0
(default) and the machine requires it, or this parameter
is set to 1, a brightness value of 0 sets the backlight
to maximum brightness, and the maximum of the brightness
value switches the backlight off.
-1 -- never invert brightness
0 -- machine default
1 -- force brightness inversion
2012-03-15 18:56:25 +04:00
2005-04-17 02:20:36 +04:00
icn= [HW,ISDN]
Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
2009-02-25 22:28:21 +03:00
ide-core.nodma= [HW] (E)IDE subsystem
Format: =0.0 to prevent dma on hda, =0.1 hdb =1.0 hdc
2009-06-07 15:52:52 +04:00
.vlb_clock .pci_clock .noflush .nohpa .noprobe .nowerr
.cdrom .chs .ignore_cable are additional options
2008-03-07 23:53:50 +03:00
See Documentation/ide/ide.txt.
2005-04-17 02:20:36 +04:00
2009-04-06 02:55:22 +04:00
ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
Claim all unknown PCI IDE storage controllers.
2007-05-02 21:27:12 +04:00
idle= [X86]
2013-02-10 10:38:39 +04:00
Format: idle=poll, idle=halt, idle=nomwait
2008-12-19 21:57:32 +03:00
Poll forces a polling idle loop that can slightly
improve the performance of waking up a idle CPU, but
will use a lot of power and make the system run hot.
Not recommended.
idle=halt: Halt is forced to be used for CPU idle.
2008-06-24 13:58:53 +04:00
In such case C2/C3 won't be used again.
2008-12-19 21:57:32 +03:00
idle=nomwait: Disable mwait for CPU C-states
2005-10-23 23:57:11 +04:00
2006-12-07 07:40:51 +03:00
ignore_loglevel [KNL]
Ignore loglevel setting - this will print /all/
kernel messages to the console. Useful for debugging.
2011-11-01 04:11:25 +04:00
We also add it as printk module parameter, so users
could change it dynamically, usually by
/sys/module/printk/parameters/ignore_loglevel.
2006-12-07 07:40:51 +03:00
2005-04-17 02:20:36 +04:00
ihash_entries= [KNL]
Set number of hash buckets for inode cache.
ima: integrity appraisal extension
IMA currently maintains an integrity measurement list used to assert the
integrity of the running system to a third party. The IMA-appraisal
extension adds local integrity validation and enforcement of the
measurement against a "good" value stored as an extended attribute
'security.ima'. The initial methods for validating 'security.ima' are
hashed based, which provides file data integrity, and digital signature
based, which in addition to providing file data integrity, provides
authenticity.
This patch creates and maintains the 'security.ima' xattr, containing
the file data hash measurement. Protection of the xattr is provided by
EVM, if enabled and configured.
Based on policy, IMA calls evm_verifyxattr() to verify a file's metadata
integrity and, assuming success, compares the file's current hash value
with the one stored as an extended attribute in 'security.ima'.
Changelov v4:
- changed iint cache flags to hex values
Changelog v3:
- change appraisal default for filesystems without xattr support to fail
Changelog v2:
- fix audit msg 'res' value
- removed unused 'ima_appraise=' values
Changelog v1:
- removed unused iint mutex (Dmitry Kasatkin)
- setattr hook must not reset appraised (Dmitry Kasatkin)
- evm_verifyxattr() now differentiates between no 'security.evm' xattr
(INTEGRITY_NOLABEL) and no EVM 'protected' xattrs included in the
'security.evm' (INTEGRITY_NOXATTRS).
- replace hash_status with ima_status (Dmitry Kasatkin)
- re-initialize slab element ima_status on free (Dmitry Kasatkin)
- include 'security.ima' in EVM if CONFIG_IMA_APPRAISE, not CONFIG_IMA
- merged half "ima: ima_must_appraise_or_measure API change" (Dmitry Kasatkin)
- removed unnecessary error variable in process_measurement() (Dmitry Kasatkin)
- use ima_inode_post_setattr() stub function, if IMA_APPRAISE not configured
(moved ima_inode_post_setattr() to ima_appraise.c)
- make sure ima_collect_measurement() can read file
Changelog:
- add 'iint' to evm_verifyxattr() call (Dimitry Kasatkin)
- fix the race condition between chmod, which takes the i_mutex and then
iint->mutex, and ima_file_free() and process_measurement(), which take
the locks in the reverse order, by eliminating iint->mutex. (Dmitry Kasatkin)
- cleanup of ima_appraise_measurement() (Dmitry Kasatkin)
- changes as a result of the iint not allocated for all regular files, but
only for those measured/appraised.
- don't try to appraise new/empty files
- expanded ima_appraisal description in ima/Kconfig
- IMA appraise definitions required even if IMA_APPRAISE not enabled
- add return value to ima_must_appraise() stub
- unconditionally set status = INTEGRITY_PASS *after* testing status,
not before. (Found by Joe Perches)
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2012-02-13 19:15:05 +04:00
ima_appraise= [IMA] appraise integrity measurements
Format: { "off" | "enforce" | "fix" }
default: "enforce"
ima: add appraise action keywords and default rules
Unlike the IMA measurement policy, the appraise policy can not be dependent
on runtime process information, such as the task uid, as the 'security.ima'
xattr is written on file close and must be updated each time the file changes,
regardless of the current task uid.
This patch extends the policy language with 'fowner', defines an appraise
policy, which appraises all files owned by root, and defines 'ima_appraise_tcb',
a new boot command line option, to enable the appraise policy.
Changelog v3:
- separate the measure from the appraise rules in order to support measuring
without appraising and appraising without measuring.
- change appraisal default for filesystems without xattr support to fail
- update default appraise policy for cgroups
Changelog v1:
- don't appraise RAMFS (Dmitry Kasatkin)
- merged rest of "ima: ima_must_appraise_or_measure API change" commit
(Dmtiry Kasatkin)
ima_must_appraise_or_measure() called ima_match_policy twice, which
searched the policy for a matching rule. Once for a matching measurement
rule and subsequently for an appraisal rule. Searching the policy twice
is unnecessary overhead, which could be noticeable with a large policy.
The new version of ima_must_appraise_or_measure() does everything in a
single iteration using a new version of ima_match_policy(). It returns
IMA_MEASURE, IMA_APPRAISE mask.
With the use of action mask only one efficient matching function
is enough. Removed other specific versions of matching functions.
Changelog:
- change 'owner' to 'fowner' to conform to the new LSM conditions posted by
Roberto Sassu.
- fix calls to ima_log_string()
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2011-03-10 06:25:48 +03:00
ima_appraise_tcb [IMA]
The builtin appraise policy appraises all files
owned by uid=0.
2009-02-04 17:06:58 +03:00
ima_hash= [IMA]
2013-06-07 14:16:37 +04:00
Format: { md5 | sha1 | rmd160 | sha256 | sha384
| sha512 | ... }
2009-02-04 17:06:58 +03:00
default: "sha1"
2013-06-07 14:16:37 +04:00
The list of supported hash algorithms is defined
in crypto/hash_info.h.
2009-05-21 23:47:06 +04:00
ima_tcb [IMA]
Load a policy which meets the needs of the Trusted
Computing Base. This means IMA will measure all
programs exec'd, files mmap'd for exec, and all files
opened for read by uid=0.
2013-06-07 14:16:35 +04:00
ima_template= [IMA]
Select one of defined IMA measurements template formats.
Formats: { "ima" | "ima-ng" }
Default: "ima-ng"
2014-02-26 19:05:20 +04:00
ima.ahash_minsize= [IMA] Minimum file size for asynchronous hash usage
Format: <min_file_size>
Set the minimal file size for using asynchronous hash.
If left unspecified, ahash usage is disabled.
ahash performance varies for different data sizes on
different crypto accelerators. This option can be used
to achieve the best performance for a particular HW.
2014-05-06 15:47:13 +04:00
ima.ahash_bufsize= [IMA] Asynchronous hash buffer size
Format: <bufsize>
Set hashing buffer size. Default: 4k.
ahash performance varies for different chunk sizes on
different crypto accelerators. This option can be used
to achieve best performance for particular HW.
2005-04-17 02:20:36 +04:00
init= [KNL]
Format: <full_path>
Run specified binary instead of /sbin/init as init
process.
initcall_debug [KNL] Trace initcalls as they are executed. Useful
for working out where the kernel is dying during
startup.
2014-06-05 03:12:17 +04:00
initcall_blacklist= [KNL] Do not execute a comma-separated list of
initcall functions. Useful for debugging built-in
modules and initcalls.
2005-04-17 02:20:36 +04:00
initrd= [BOOT] Specify the location of the initial ramdisk
inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
Format: <irq>
2013-05-21 23:35:17 +04:00
int_pln_enable [x86] Enable power limit notification interrupt
2013-03-18 22:48:02 +04:00
integrity_audit=[IMA]
Format: { "0" | "1" }
0 -- basic integrity auditing messages. (Default)
1 -- additional integrity auditing messages.
2007-10-22 03:41:49 +04:00
intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option
2009-02-05 01:29:19 +03:00
on
Enable intel iommu driver.
2007-10-22 03:41:49 +04:00
off
Disable intel iommu driver.
igfx_off [Default Off]
By default, gfx is mapped as normal device. If a gfx
device has a dedicated DMAR unit, the DMAR unit is
bypassed by not enabling DMAR with this option. In
this case, gfx device will use physical address for
DMA.
2007-10-22 03:41:53 +04:00
forcedac [x86_64]
With this option iommu will not optimize to look
2011-08-13 23:34:52 +04:00
for io virtual address below 32-bit forcing dual
2007-10-22 03:41:53 +04:00
address cycle on pci bus for cards supporting greater
2011-08-13 23:34:52 +04:00
than 32-bit addressing. The default is to look
for translation below 32-bit and if not available
2007-10-22 03:41:53 +04:00
then look in the higher range.
2008-03-05 02:22:08 +03:00
strict [Default Off]
With this option on every unmap_single operation will
result in a hardware IOTLB flush operation as opposed
to batching them for performance.
intel-iommu: Enable super page (2MiB, 1GiB, etc.) support
There are no externally-visible changes with this. In the loop in the
internal __domain_mapping() function, we simply detect if we are mapping:
- size >= 2MiB, and
- virtual address aligned to 2MiB, and
- physical address aligned to 2MiB, and
- on hardware that supports superpages.
(and likewise for larger superpages).
We automatically use a superpage for such mappings. We never have to
worry about *breaking* superpages, since we trust that we will always
*unmap* the same range that was mapped. So all we need to do is ensure
that dma_pte_clear_range() will also cope with superpages.
Adjust pfn_to_dma_pte() to take a superpage 'level' as an argument, so
it can return a PTE at the appropriate level rather than always
extending the page tables all the way down to level 1. Again, this is
simplified by the fact that we should never encounter existing small
pages when we're creating a mapping; any old mapping that used the same
virtual range will have been entirely removed and its obsolete page
tables freed.
Provide an 'intel_iommu=sp_off' argument on the command line as a
chicken bit. Not that it should ever be required.
==
The original commit seen in the iommu-2.6.git was Youquan's
implementation (and completion) of my own half-baked code which I'd
typed into an email. Followed by half a dozen subsequent 'fixes'.
I've taken the unusual step of rewriting history and collapsing the
original commits in order to keep the main history simpler, and make
life easier for the people who are going to have to backport this to
older kernels. And also so I can give it a more coherent commit comment
which (hopefully) gives a better explanation of what's going on.
The original sequence of commits leading to identical code was:
Youquan Song (3):
intel-iommu: super page support
intel-iommu: Fix superpage alignment calculation error
intel-iommu: Fix superpage level calculation error in dma_pfn_level_pte()
David Woodhouse (4):
intel-iommu: Precalculate superpage support for dmar_domain
intel-iommu: Fix hardware_largepage_caps()
intel-iommu: Fix inappropriate use of superpages in __domain_mapping()
intel-iommu: Fix phys_pfn in __domain_mapping for sglist pages
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25 22:13:49 +04:00
sp_off [Default Off]
By default, super page will be supported if Intel IOMMU
has the capability. With this option, super page will
not be supported.
2011-12-14 20:18:52 +04:00
intel_idle.max_cstate= [KNL,HW,ACPI,X86]
0 disables intel_idle and fall back on acpi_idle.
1 to 6 specify maximum depth of C-state.
2013-02-16 01:55:10 +04:00
intel_pstate= [X86]
disable
Do not enable intel_pstate as the default
scaling driver for the supported processors
2010-07-20 22:06:49 +04:00
intremap= [X86-64, Intel-IOMMU]
on enable Interrupt Remapping (default)
off disable Interrupt Remapping
nosid disable Source ID checking
2011-08-24 04:05:18 +04:00
no_x2apic_optout
BIOS x2APIC opt-out request will be ignored
2010-07-20 22:06:49 +04:00
2009-04-06 02:55:22 +04:00
iomem= Disable strict checking of access to MMIO memory
strict regions from userspace.
relaxed
iommu= [x86]
off
force
noforce
biomerge
panic
nopanic
merge
nomerge
forcesac
soft
2011-10-21 23:56:24 +04:00
pt [x86, IA-64]
2009-04-06 02:55:22 +04:00
io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in
arch/alpha/kernel/core_marvel.c.
2009-04-14 12:33:43 +04:00
io_delay= [X86] I/O delay method
2008-01-30 15:30:05 +03:00
0x80
Standard port 0x80 based delay
0xed
Alternate port 0xed based delay (needed on some systems)
2008-01-30 15:30:05 +03:00
udelay
2008-01-30 15:30:05 +03:00
Simple two microseconds delay
none
No delay
2008-01-30 15:30:05 +03:00
2005-04-17 02:20:36 +04:00
ip= [IP_PNP]
2009-10-27 21:41:35 +03:00
See Documentation/filesystems/nfs/nfsroot.txt.
2005-04-17 02:20:36 +04:00
2005-06-29 07:45:18 +04:00
irqfixup [HW]
When an interrupt is not handled search all handlers
for it. Intended to get systems with badly broken
firmware running.
irqpoll [HW]
When an interrupt is not handled search all handlers
for it. Also check all handlers each timer
interrupt. Intended to get systems with badly broken
firmware running.
2005-04-17 02:20:36 +04:00
isapnp= [ISAPNP]
2005-10-23 23:57:11 +04:00
Format: <RDP>,<reset>,<pci_scan>,<verbosity>
2005-04-17 02:20:36 +04:00
isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
2006-12-07 07:37:11 +03:00
Format:
<cpu number>,...,<cpu number>
or
2008-11-06 23:53:39 +03:00
<cpu number>-<cpu number>
(must be a positive range in ascending order)
2006-12-07 07:37:11 +03:00
or a mixture
<cpu number>,...,<cpu number>-<cpu number>
2008-11-06 23:53:39 +03:00
2005-04-17 02:20:36 +04:00
This option can be used to specify one or more CPUs
to isolate from the general SMP balancing and scheduling
2008-11-06 23:53:39 +03:00
algorithms. You can move a process onto or off an
"isolated" CPU via the CPU affinity syscalls or cpuset.
2005-04-17 02:20:36 +04:00
<cpu number> begins at 0 and the maximum value is
"number of CPUs in system - 1".
This option is the preferred way to isolate CPUs. The
2005-10-23 23:57:11 +04:00
alternative -- manually setting the CPU mask of all
tasks in the system -- can cause problems and
suboptimal load balancer performance.
2005-04-17 02:20:36 +04:00
2005-10-23 23:57:11 +04:00
iucv= [HW,NET]
2005-04-17 02:20:36 +04:00
2013-04-09 23:27:19 +04:00
ivrs_ioapic [HW,X86_64]
Provide an override to the IOAPIC-ID<->DEVICE-ID
mapping provided in the IVRS ACPI table. For
example, to map IOAPIC-ID decimal 10 to
PCI device 00:14.0 write the parameter as:
ivrs_ioapic[10]=00:14.0
ivrs_hpet [HW,X86_64]
Provide an override to the HPET-ID<->DEVICE-ID
mapping provided in the IVRS ACPI table. For
example, to map HPET-ID decimal 0 to
PCI device 00:14.0 write the parameter as:
ivrs_hpet[0]=00:14.0
2005-04-17 02:20:36 +04:00
js= [HW,JOY] Analog joystick
See Documentation/input/joystick.txt.
2014-06-14 00:30:36 +04:00
kaslr/nokaslr [X86]
Enable/disable kernel and module base offset ASLR
(Address Space Layout Randomization) if built into
the kernel. When CONFIG_HIBERNATION is selected,
kASLR is disabled by default. When kASLR is enabled,
hibernation will be disabled.
2009-04-06 02:55:22 +04:00
keepinitrd [HW,ARM]
2009-04-14 12:33:43 +04:00
kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
2007-07-17 15:03:14 +04:00
specifies the amount of memory usable by the kernel
for non-movable allocations. The requested amount is
spread evenly throughout all nodes in the system. The
remaining memory in each node is used for Movable
pages. In the event, a node is too small to have both
kernelcore and Movable pages, kernelcore pages will
take priority and other nodes will have a larger number
2013-10-01 00:45:10 +04:00
of Movable pages. The Movable zone is used for the
2007-07-17 15:03:14 +04:00
allocation of pages that may be reclaimed or moved
by the page migration subsystem. This means that
HugeTLB pages may not be allocated from this zone.
Note that allocations like PTEs-from-HighMem still
use the HighMem zone if it exists, and the Normal
zone if it does not.
2010-05-21 06:04:31 +04:00
kgdbdbgp= [KGDB,HW] kgdb over EHCI usb debug port.
Format: <Controller#>[,poll interval]
The controller # is the number of the ehci usb debug
port as it is probed via PCI. The poll interval is
optional and is the number seconds in between
each poll cycle to the debug port in case you need
the functionality for interrupting the kernel with
gdb or control-c on the dbgp connection. When
not using this parameter you use sysrq-g to break into
the kernel debugger.
2010-05-21 06:04:24 +04:00
kgdboc= [KGDB,HW] kgdb over consoles.
2010-05-21 06:04:24 +04:00
Requires a tty driver that supports console polling,
or a supported polling keyboard driver (non-usb).
2010-08-05 18:22:33 +04:00
Serial only format: <serial_device>[,baud]
keyboard only format: kbd
keyboard and serial format: kbd,<serial_device>[,baud]
Optional Kernel mode setting:
kms, kbd format: kms,kbd
kms, kbd and serial format: kms,kbd,<ser_dev>[,baud]
2008-04-17 22:05:38 +04:00
2010-05-21 06:04:24 +04:00
kgdbwait [KGDB] Stop kernel execution and enter the
kernel debugger at the earliest opportunity.
2008-08-23 20:54:37 +04:00
kmac= [MIPS] korina ethernet MAC address.
Configure the RouterBoard 532 series on-chip
Ethernet adapter MAC address.
2009-06-11 16:22:39 +04:00
kmemleak= [KNL] Boot-time kmemleak enable/disable
Valid arguments: on, off
Default: on
2014-01-24 03:53:33 +04:00
kmemcheck= [X86] Boot-time kmemcheck enable/disable/one-shot mode
Valid arguments: 0, 1, 2
kmemcheck=0 (disabled)
kmemcheck=1 (enabled)
kmemcheck=2 (one-shot mode)
Default: 2 (one-shot mode)
2009-04-14 12:33:43 +04:00
kstack=N [X86] Print N words from the kernel stack
2009-04-06 02:55:22 +04:00
in oops dumps.
2009-07-10 16:20:35 +04:00
kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs.
Default is 0 (don't ignore, but inject #GP)
2010-09-20 18:17:48 +04:00
kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit
KVM MMU at runtime.
2009-07-10 16:20:35 +04:00
Default is 0 (off)
kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM.
2010-09-20 18:16:45 +04:00
Default is 1 (enabled)
2009-07-10 16:20:35 +04:00
kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU)
for all guests.
2011-08-13 23:34:52 +04:00
Default is 1 (enabled) if in 64-bit or 32-bit PAE mode.
2009-07-10 16:20:35 +04:00
kvm-intel.ept= [KVM,Intel] Disable extended page tables
(virtualized MMU) support on capable Intel chips.
Default is 1 (enabled)
kvm-intel.emulate_invalid_guest_state=
[KVM,Intel] Enable emulation of invalid guest states
Default is 0 (disabled)
kvm-intel.flexpriority=
[KVM,Intel] Disable FlexPriority feature (TPR shadow).
Default is 1 (enabled)
2011-08-09 15:28:35 +04:00
kvm-intel.nested=
[KVM,Intel] Enable VMX nesting (nVMX).
Default is 0 (disabled)
2009-07-10 16:20:35 +04:00
kvm-intel.unrestricted_guest=
[KVM,Intel] Disable unrestricted guest feature
(virtualized real and unpaged mode) on capable
Intel chips. Default is 1 (enabled)
kvm-intel.vpid= [KVM,Intel] Disable Virtual Processor Identification
feature (tagged TLBs) on capable Intel chips.
Default is 1 (enabled)
2005-04-17 02:20:36 +04:00
l2cr= [PPC]
2008-03-28 23:20:23 +03:00
l3cr= [PPC]
2007-07-31 11:37:59 +04:00
lapic [X86-32,APIC] Enable the local APIC even if BIOS
2005-10-23 23:57:11 +04:00
disabled it.
2005-04-17 02:20:36 +04:00
2012-10-23 01:37:58 +04:00
lapic= [x86,APIC] "notscdeadline" Do not use TSC deadline
value for LAPIC timer one-shot implementation. Default
back to the programmable timer unit in the LAPIC.
2009-04-14 12:33:43 +04:00
lapic_timer_c2_ok [X86,APIC] trust the local apic timer
2008-12-19 21:57:32 +03:00
in C2 power state.
2007-03-23 18:08:01 +03:00
2008-01-06 21:08:56 +03:00
libata.dma= [LIBATA] DMA control
libata.dma=0 Disable all PATA and SATA DMA
libata.dma=1 PATA and SATA Disk DMA only
libata.dma=2 ATAPI (CDROM) DMA only
2011-08-13 23:34:52 +04:00
libata.dma=4 Compact Flash DMA only
2008-01-06 21:08:56 +03:00
Combinations also work, so libata.dma=3 enables DMA
for disks and CDROMs, but not CFs.
2011-08-13 23:34:52 +04:00
2009-08-06 02:14:10 +04:00
libata.ignore_hpa= [LIBATA] Ignore HPA limit
libata.ignore_hpa=0 keep BIOS limits (default)
libata.ignore_hpa=1 ignore limits, using full disk
2008-01-06 21:08:56 +03:00
2007-09-27 19:50:13 +04:00
libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume
when set.
Format: <int>
2008-02-13 03:15:09 +03:00
libata.force= [LIBATA] Force configurations. The format is comma
separated list of "[ID:]VAL" where ID is
2010-04-21 14:17:12 +04:00
PORT[.DEVICE]. PORT and DEVICE are decimal numbers
2008-02-13 03:15:09 +03:00
matching port, link or device. Basically, it matches
the ATA ID string printed on console by libata. If
the whole ID part is omitted, the last PORT and DEVICE
values are used. If ID hasn't been specified yet, the
configuration applies to all ports, links and devices.
If only DEVICE is omitted, the parameter applies to
the port and all links and devices behind it. DEVICE
number of 0 either selects the first device or the
first fan-out link behind PMP device. It does not
select the host link. DEVICE number of 15 selects the
host link and device attached to it.
The VAL specifies the configuration to force. As long
as there's no ambiguity shortcut notation is allowed.
For example, both 1.5 and 1.5G would work for 1.5Gbps.
The following configurations can be forced.
* Cable type: 40c, 80c, short40c, unk, ign or sata.
Any ID with matching PORT is used.
* SATA link speed limit: 1.5Gbps or 3.0Gbps.
* Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
udma[/][16,25,33,44,66,100,133] notation is also
allowed.
* [no]ncq: Turn on or off NCQ.
2008-08-13 15:19:09 +04:00
* nohrst, nosrst, norst: suppress hard, soft
and both resets.
2012-06-22 10:41:41 +04:00
* rstonce: only attempt one reset during
hot-unplug link recovery
2010-05-23 14:59:11 +04:00
* dump_id: dump IDENTIFY data.
2013-05-22 00:30:58 +04:00
* atapi_dmadir: Enable ATAPI DMADIR bridge support
2013-12-16 21:31:19 +04:00
* disable: Disable this device.
2008-02-13 03:15:09 +03:00
If there are multiple matching configurations changing
the same attribute, the last one is used.
2010-07-12 08:36:09 +04:00
memblock=debug [KNL] Enable memblock debug messages.
2009-01-07 01:42:44 +03:00
2005-04-17 02:20:36 +04:00
load_ramdisk= [RAM] List of ramdisks to load from floppy
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/ramdisk.txt.
2005-04-17 02:20:36 +04:00
2006-01-15 00:21:19 +03:00
lockd.nlm_grace_period=P [NFS] Assign grace period.
Format: <integer>
2005-04-17 02:20:36 +04:00
2006-01-15 00:21:19 +03:00
lockd.nlm_tcpport=N [NFS] Assign TCP port.
Format: <integer>
lockd.nlm_timeout=T [NFS] Assign timeout value.
Format: <integer>
lockd.nlm_udpport=M [NFS] Assign UDP port.
Format: <integer>
2005-04-17 02:20:36 +04:00
logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
Format: <irq>
loglevel= All Kernel Messages with a loglevel smaller than the
console loglevel will be printed to the console. It can
also be changed with klogd or other programs. The
loglevels are defined as follows:
0 (KERN_EMERG) system is unusable
1 (KERN_ALERT) action must be taken immediately
2 (KERN_CRIT) critical conditions
3 (KERN_ERR) error conditions
4 (KERN_WARNING) warning conditions
5 (KERN_NOTICE) normal but significant condition
6 (KERN_INFO) informational
7 (KERN_DEBUG) debug-level messages
2011-02-21 07:08:35 +03:00
log_buf_len=n[KMG] Sets the size of the printk ring buffer,
2014-08-07 03:08:56 +04:00
in bytes. n must be a power of two and greater
than the minimal size. The minimal size is defined
by LOG_BUF_SHIFT kernel config parameter. There is
also CONFIG_LOG_CPU_MAX_BUF_SHIFT config parameter
that allows to increase the default size depending on
the number of CPUs. See init/Kconfig for more details.
2005-04-17 02:20:36 +04:00
2007-10-16 12:29:37 +04:00
logo.nologo [FB] Disables display of the built-in Linux logo.
This may be used to provide more screen space for
kernel log messages and is useful when debugging
kernel boot problems.
2005-04-17 02:20:36 +04:00
lp=0 [LP] Specify parallel ports to use, e.g,
lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
lp=reset first parallel port). 'lp=0' disables the
lp=auto printer driver. 'lp=reset' (which can be
specified in addition to the ports) causes
attached printers to be reset. Using
lp=port1,port2,... specifies the parallel ports
to associate lp devices with, starting with
lp0. A port specification may be 'none' to skip
that lp device, or a parport name such as
'parport0'. Specifying 'lp=auto' instead of a
port specification list means that device IDs
from each port should be examined, to see if
an IEEE 1284-compliant printer is attached; if
so, the driver will manage that printer.
See also header of drivers/char/lp.c.
lpj=n [KNL]
Sets loops_per_jiffy to given constant, thus avoiding
time-consuming boot-time autodetection (up to 250 ms per
CPU). 0 enables autodetection (default). To determine
the correct value for your kernel, boot with normal
autodetection and see what value is printed. Note that
on SMP systems the preset will be applied to all CPUs,
which is likely to cause problems if your CPUs need
significantly divergent settings. An incorrect value
will cause delays in the kernel to be wrong, leading to
unpredictable I/O errors and other breakage. Although
unlikely, in the extreme case this might damage your
hardware.
ltpc= [NET]
Format: <io>,<irq>,<dma>
2011-08-13 23:34:52 +04:00
machvec= [IA-64] Force the use of a particular machine-vector
2005-10-23 23:57:11 +04:00
(machvec) in a generic kernel.
Example: machvec=hpzx1_swiotlb
2005-04-17 02:20:36 +04:00
2009-07-02 19:27:12 +04:00
machtype= [Loongson] Share the same kernel image file between different
yeeloong laptop.
Example: machtype=lemote-yeeloong-2f-7inch
2009-04-06 02:55:22 +04:00
max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater
than or equal to this physical address is ignored.
2005-04-17 02:20:36 +04:00
maxcpus= [SMP] Maximum number of processors that an SMP kernel
2007-08-16 11:34:22 +04:00
should make use of. maxcpus=n : n >= 0 limits the
kernel to using 'n' processors. n=0 is a special case,
it is equivalent to "nosmp", which also disables
the IO APIC.
2005-04-17 02:20:36 +04:00
2011-08-01 00:08:04 +04:00
max_loop= [LOOP] The number of loop block devices that get
(loop.max_loop) unconditionally pre-created at init time. The default
number is configured by BLK_DEV_LOOP_MIN_COUNT. Instead
of statically allocating a predefined number, loop
devices can be requested on-demand with the
/dev/loop-control interface.
2005-06-30 05:00:00 +04:00
2007-07-31 11:37:59 +04:00
mce [X86-32] Machine Check Exception
2005-04-17 02:20:36 +04:00
2008-10-20 20:32:21 +04:00
mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt
2007-10-17 20:04:38 +04:00
2005-04-17 02:20:36 +04:00
md= [HW] RAID subsystems devices and level
See Documentation/md.txt.
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
mdacon= [MDA]
Format: <first>,<last>
Specifies range of consoles to be captured by the MDA.
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
Amount of memory to be used when the kernel is not able
to see the whole system memory or for test.
2012-12-18 03:59:29 +04:00
[X86] Work as limiting max address. Use together
with memmap= to avoid physical address space collisions.
Without memmap= PCI devices could be placed at addresses
belonging to unused RAM.
2005-04-17 02:20:36 +04:00
2007-07-31 11:37:59 +04:00
mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
2005-04-17 02:20:36 +04:00
memory.
2008-09-21 12:14:42 +04:00
memchunk=nn[KMG]
[KNL,SH] Allow user to override the default size for
per-device physically contiguous DMA buffers.
2009-04-14 12:33:43 +04:00
memmap=exactmap [KNL,X86] Enable setting of an exact
2005-04-17 02:20:36 +04:00
E820 memory map, as specified by the user.
Such memmap=exactmap lines can be constructed based on
BIOS output or other requirements. See the memmap=nn@ss
option description.
memmap=nn[KMG]@ss[KMG]
2014-02-07 00:04:19 +04:00
[KNL] Force usage of a specific region of memory.
Region of memory to be used is from ss to ss+nn.
2005-04-17 02:20:36 +04:00
memmap=nn[KMG]#ss[KMG]
[KNL,ACPI] Mark specific memory as ACPI data.
2014-02-07 00:04:19 +04:00
Region of memory to be marked is from ss to ss+nn.
2005-04-17 02:20:36 +04:00
memmap=nn[KMG]$ss[KMG]
[KNL,ACPI] Mark specific memory as reserved.
2014-02-07 00:04:19 +04:00
Region of memory to be reserved is from ss to ss+nn.
2008-03-24 22:29:43 +03:00
Example: Exclude memory from 0x18690000-0x1869ffff
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000
2005-04-17 02:20:36 +04:00
2008-09-07 12:51:34 +04:00
memory_corruption_check=0/1 [X86]
Some BIOSes seem to corrupt the first 64k of
memory when doing things like suspend/resume.
Setting this option will scan the memory
looking for corruption. Enabling this will
both detect corruption and prevent the kernel
from using the memory being corrupted.
However, its 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.
memory_corruption_check_size=size [X86]
By default it checks for corruption in the low
64k, making this memory unavailable for normal
use. Use this parameter to scan for
corruption in more or less memory.
memory_corruption_check_period=seconds [X86]
By default it checks for corruption every 60
seconds. Use this parameter to check at some
other rate. 0 disables periodic checking.
2008-07-15 11:03:44 +04:00
memtest= [KNL,X86] Enable memtest
2008-03-22 04:56:19 +03:00
Format: <integer>
default : 0 <disable>
2009-02-25 13:30:45 +03:00
Specifies the number of memtest passes to be
performed. Each pass selects another test
pattern from a given set of patterns. Memtest
fills the memory with this pattern, validates
memory contents and reserves bad memory
regions that are detected.
2008-03-22 04:56:19 +03:00
2005-04-17 02:20:36 +04:00
meye.*= [HW] Set MotionEye Camera parameters
See Documentation/video4linux/meye.txt.
2007-10-13 01:04:06 +04:00
mfgpt_irq= [IA-32] Specify the IRQ to use for the
Multi-Function General Purpose Timers on AMD Geode
platforms.
2008-01-30 15:33:33 +03:00
mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
the BIOS has incorrectly applied a workaround. TinyBIOS
version 0.98 is known to be affected, 0.99 fixes the
problem by letting the user disable the workaround.
2005-04-17 02:20:36 +04:00
mga= [HW,DRM]
2008-11-20 02:36:16 +03:00
min_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory below this
physical address is ignored.
2009-05-20 14:10:31 +04:00
mini2440= [ARM,HW,KNL]
Format:[0..2][b][c][t]
Default: "0tb"
MINI2440 configuration specification:
0 - The attached screen is the 3.5" TFT
1 - The attached screen is the 7" TFT
2 - The VGA Shield is attached (1024x768)
Leaving out the screen size parameter will not load
the TFT driver, and the framebuffer will be left
unconfigured.
b - Enable backlight. The TFT backlight pin will be
linked to the kernel VESA blanking code and a GPIO
LED. This parameter is not necessary when using the
VGA shield.
c - Enable the s3c camera interface.
t - Reserved for enabling touchscreen support. The
touchscreen support is not enabled in the mainstream
kernel as of 2.6.30, a preliminary port can be found
in the "bleeding edge" mini2440 support kernel at
http://repo.or.cz/w/linux-2.6/mini2440.git
2008-07-24 08:26:49 +04:00
mminit_loglevel=
[KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
parameter allows control of the logging verbosity for
the additional memory initialisation checks. A value
of 0 disables mminit logging and a level of 4 will
log everything. Information is printed at KERN_DEBUG
so loglevel=8 may also need to be specified.
2012-09-26 13:09:40 +04:00
module.sig_enforce
[KNL] When CONFIG_MODULE_SIG is set, this means that
modules without (valid) signatures will fail to load.
2013-03-25 23:42:06 +04:00
Note that if CONFIG_MODULE_SIG_FORCE is set, that
2012-09-26 13:09:40 +04:00
is always true, so this option does nothing.
2005-04-17 02:20:36 +04:00
mousedev.tap_time=
[MOUSE] Maximum time between finger touching and
leaving touchpad surface for touch to be considered
a tap and be reported as a left button click (for
touchpads working in absolute mode only).
Format: <msecs>
mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
reporting absolute coordinates, such as tablets
mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
reporting absolute coordinates, such as tablets
2009-04-14 12:33:43 +04:00
movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
2009-04-06 02:55:22 +04:00
is similar to kernelcore except it specifies the
amount of memory used for migratable allocations.
If both kernelcore and movablecore is specified,
then kernelcore will be at *least* the specified
value but may be more. If movablecore on its own
is specified, the administrator must be careful
that the amount of memory usable for all allocations
is not too small.
mem-hotplug: introduce movable_node boot option
The hot-Pluggable field in SRAT specifies which memory is hotpluggable.
As we mentioned before, if hotpluggable memory is used by the kernel, it
cannot be hot-removed. So memory hotplug users may want to set all
hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it.
Memory hotplug users may also set a node as movable node, which has
ZONE_MOVABLE only, so that the whole node can be hot-removed.
But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the
kernel cannot use memory in movable nodes. This will cause NUMA
performance down. And other users may be unhappy.
So we need a way to allow users to enable and disable this functionality.
In this patch, we introduce movable_node boot option to allow users to
choose to not to consume hotpluggable memory at early boot time and later
we can set it as ZONE_MOVABLE.
To achieve this, the movable_node boot option will control the memblock
allocation direction. That said, after memblock is ready, before SRAT is
parsed, we should allocate memory near the kernel image as we explained in
the previous patches. So if movable_node boot option is set, the kernel
does the following:
1. After memblock is ready, make memblock allocate memory bottom up.
2. After SRAT is parsed, make memblock behave as default, allocate memory
top down.
Users can specify "movable_node" in kernel commandline to enable this
functionality. For those who don't use memory hotplug or who don't want
to lose their NUMA performance, just don't specify anything. The kernel
will work as before.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Suggested-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 03:08:10 +04:00
movable_node [KNL,X86] Boot-time switch to enable the effects
of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details.
2005-04-17 02:20:36 +04:00
MTD_Partition= [MTD]
Format: <name>,<region-number>,<size>,<offset>
2005-10-23 23:57:11 +04:00
MTD_Region= [MTD] Format:
<name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
2005-04-17 02:20:36 +04:00
mtdparts= [MTD]
2007-07-31 11:37:40 +04:00
See drivers/mtd/cmdlinepart.c.
2005-04-17 02:20:36 +04:00
2010-09-28 19:33:12 +04:00
multitce=off [PPC] This parameter disables the use of the pSeries
firmware feature for updating multiple TCE entries
at a time.
2009-05-13 00:46:57 +04:00
onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
Format: [die0_boundary][,die0_lock][,die1_boundary][,die1_lock]
boundary - index of last SLC block on Flex-OneNAND.
The remaining blocks are configured as MLC blocks.
lock - Configure if Flex-OneNAND boundary should be locked.
Once locked, the boundary cannot be changed.
1 indicates lock status, 0 indicates unlock status.
2008-07-03 14:24:29 +04:00
mtdset= [ARM]
ARM/S3C2412 JIVE boot control
See arch/arm/mach-s3c2412/mach-jive.c
2005-04-17 02:20:36 +04:00
mtouchusb.raw_coordinates=
2005-10-23 23:57:11 +04:00
[HW] Make the MicroTouch USB driver use raw coordinates
('y', default) or cooked coordinates ('n')
2005-04-17 02:20:36 +04:00
2009-04-06 02:55:22 +04:00
mtrr_chunk_size=nn[KMG] [X86]
2009-04-27 17:06:31 +04:00
used for mtrr cleanup. It is largest continuous chunk
2009-04-06 02:55:22 +04:00
that could hold holes aka. UC entries.
mtrr_gran_size=nn[KMG] [X86]
Used for mtrr cleanup. It is granularity of mtrr block.
Default is 1.
Large value could prevent small alignment from
using up MTRRs.
mtrr_spare_reg_nr=n [X86]
Format: <integer>
Range: 0,7 : spare reg number
Default : 1
Used for mtrr cleanup. It is spare mtrr entries number.
Set to 2 or more if your graphical card needs more.
2005-04-17 02:20:36 +04:00
n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
netdev= [NET] Network devices parameters
Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
Note that mem_start is often overloaded to mean
something different and driver-specific.
2005-10-23 23:57:11 +04:00
This usage is only documented in each driver source
file if at all.
netfilter: accounting rework: ct_extend + 64bit counters (v4)
Initially netfilter has had 64bit counters for conntrack-based accounting, but
it was changed in 2.6.14 to save memory. Unfortunately in-kernel 64bit counters are
still required, for example for "connbytes" extension. However, 64bit counters
waste a lot of memory and it was not possible to enable/disable it runtime.
This patch:
- reimplements accounting with respect to the extension infrastructure,
- makes one global version of seq_print_acct() instead of two seq_print_counters(),
- makes it possible to enable it at boot time (for CONFIG_SYSCTL/CONFIG_SYSFS=n),
- makes it possible to enable/disable it at runtime by sysctl or sysfs,
- extends counters from 32bit to 64bit,
- renames ip_conntrack_counter -> nf_conn_counter,
- enables accounting code unconditionally (no longer depends on CONFIG_NF_CT_ACCT),
- set initial accounting enable state based on CONFIG_NF_CT_ACCT
- removes buggy IPCT_COUNTER_FILLING event handling.
If accounting is enabled newly created connections get additional acct extend.
Old connections are not changed as it is not possible to add a ct_extend area
to confirmed conntrack. Accounting is performed for all connections with
acct extend regardless of a current state of "net.netfilter.nf_conntrack_acct".
Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-21 21:01:34 +04:00
nf_conntrack.acct=
[NETFILTER] Enable connection tracking flow accounting
0 to disable accounting
1 to enable accounting
2010-06-25 16:46:56 +04:00
Default value is 0.
netfilter: accounting rework: ct_extend + 64bit counters (v4)
Initially netfilter has had 64bit counters for conntrack-based accounting, but
it was changed in 2.6.14 to save memory. Unfortunately in-kernel 64bit counters are
still required, for example for "connbytes" extension. However, 64bit counters
waste a lot of memory and it was not possible to enable/disable it runtime.
This patch:
- reimplements accounting with respect to the extension infrastructure,
- makes one global version of seq_print_acct() instead of two seq_print_counters(),
- makes it possible to enable it at boot time (for CONFIG_SYSCTL/CONFIG_SYSFS=n),
- makes it possible to enable/disable it at runtime by sysctl or sysfs,
- extends counters from 32bit to 64bit,
- renames ip_conntrack_counter -> nf_conn_counter,
- enables accounting code unconditionally (no longer depends on CONFIG_NF_CT_ACCT),
- set initial accounting enable state based on CONFIG_NF_CT_ACCT
- removes buggy IPCT_COUNTER_FILLING event handling.
If accounting is enabled newly created connections get additional acct extend.
Old connections are not changed as it is not possible to add a ct_extend area
to confirmed conntrack. Accounting is performed for all connections with
acct extend regardless of a current state of "net.netfilter.nf_conntrack_acct".
Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-21 21:01:34 +04:00
2010-09-17 18:54:37 +04:00
nfsaddrs= [NFS] Deprecated. Use ip= instead.
2009-10-27 21:41:35 +03:00
See Documentation/filesystems/nfs/nfsroot.txt.
2005-04-17 02:20:36 +04:00
nfsroot= [NFS] nfs root filesystem for disk-less boxes.
2009-10-27 21:41:35 +03:00
See Documentation/filesystems/nfs/nfsroot.txt.
2005-04-17 02:20:36 +04:00
2010-09-17 18:54:37 +04:00
nfsrootdebug [NFS] enable nfsroot debugging messages.
See Documentation/filesystems/nfs/nfsroot.txt.
2006-01-03 11:55:41 +03:00
nfs.callback_tcpport=
[NFS] set the TCP port on which the NFSv4 callback
channel should listen.
2009-08-20 02:12:27 +04:00
nfs.cache_getent=
[NFS] sets the pathname to the program which is used
to update the NFS client cache entries.
nfs.cache_getent_timeout=
[NFS] sets the timeout after which an attempt to
update a cache entry is deemed to have failed.
2006-01-03 11:55:57 +03:00
nfs.idmap_cache_timeout=
[NFS] set the maximum lifetime for idmapper cache
entries.
2007-10-09 20:01:04 +04:00
nfs.enable_ino64=
[NFS] enable 64-bit inode numbers.
If zero, the NFS client will fake up a 32-bit inode
number for the readdir() and stat() syscalls instead
of returning the full 64-bit number.
The default is to return 64-bit inode numbers.
2012-02-07 04:50:40 +04:00
nfs.max_session_slots=
[NFSv4.1] Sets the maximum number of session slots
the client will attempt to negotiate with the server.
This limits the number of simultaneous RPC requests
that the client can send to the NFSv4.1 server.
Note that there is little point in setting this
value higher than the max_tcp_slot_table_limit.
2011-02-23 02:44:32 +03:00
nfs.nfs4_disable_idmapping=
2012-01-09 22:46:26 +04:00
[NFSv4] When set to the default of '1', this option
ensures that both the RPC level authentication
scheme and the NFS level operations agree to use
numeric uids/gids if the mount is using the
'sec=sys' security flavour. In effect it is
disabling idmapping, which can make migration from
legacy NFSv2/v3 systems to NFSv4 easier.
Servers that do not support this mode of operation
will be autodetected by the client, and it will fall
back to using the idmapper.
To turn off this behaviour, set the value to '0'.
2012-09-15 01:24:41 +04:00
nfs.nfs4_unique_id=
[NFS4] Specify an additional fixed unique ident-
ification string that NFSv4 clients can insert into
their nfs_client_id4 string. This is typically a
UUID that is generated at system install time.
2011-02-23 02:44:32 +03:00
2012-02-18 00:20:24 +04:00
nfs.send_implementation_id =
[NFSv4.1] Send client implementation identification
information in exchange_id requests.
If zero, no implementation identification information
will be sent.
The default is to send the implementation identification
information.
2013-09-04 18:08:54 +04:00
nfs.recover_lost_locks =
[NFSv4] Attempt to recover locks that were lost due
to a lease timeout on the server. Please note that
doing this risks data corruption, since there are
no guarantees that the file will remain unchanged
after the locks are lost.
If you want to enable the kernel legacy behaviour of
attempting to recover these locks, then set this
parameter to '1'.
The default parameter value of '0' causes the kernel
not to attempt recovery of lost locks.
2012-02-18 00:20:24 +04:00
2012-03-23 00:07:18 +04:00
nfsd.nfs4_disable_idmapping=
[NFSv4] When set to the default of '1', the NFSv4
server will return only numeric uids and gids to
clients using auth_sys, and will accept numeric uids
and gids from such clients. This is intended to ease
migration from NFSv2/v3.
2012-02-18 00:20:24 +04:00
2012-03-20 07:47:58 +04:00
objlayoutdriver.osd_login_prog=
[NFS] [OBJLAYOUT] sets the pathname to the program which
is used to automatically discover and login into new
osd-targets. Please see:
Documentation/filesystems/pnfs.txt for more explanations
2009-09-01 12:38:32 +04:00
nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take
2007-10-10 16:58:29 +04:00
when a NMI is triggered.
Format: [state][,regs][,debounce][,die]
2009-04-14 12:33:43 +04:00
nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
2011-03-23 02:34:16 +03:00
Format: [panic,][nopanic,][num]
2010-11-30 01:07:17 +03:00
Valid num: 0
2008-11-01 18:06:51 +03:00
0 - turn nmi_watchdog off
2009-04-06 02:55:22 +04:00
When panic is specified, panic when an NMI watchdog
2011-03-23 02:34:16 +03:00
timeout occurs (or 'nopanic' to override the opposite
default).
2009-04-06 02:55:22 +04:00
This is useful when you use a panic=... timeout and
need the box quickly up again.
2005-04-17 02:20:36 +04:00
2009-07-08 22:10:56 +04:00
netpoll.carrier_timeout=
[NET] Specifies amount of time (in seconds) that
netpoll should wait for a carrier. By default netpoll
waits 4 seconds.
2007-07-31 11:37:59 +04:00
no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
2005-04-17 02:20:36 +04:00
emulation library even if a 387 maths coprocessor
is present.
2009-04-06 02:55:22 +04:00
no_console_suspend
[HW] Never suspend the console
Disable suspending of consoles during suspend and
hibernate operations. Once disabled, debugging
messages can reach various consoles while the rest
of the system is being put to sleep (ie, while
debugging driver suspend/resume hooks). This may
not work reliably with all consoles, but is known
to work with serial and VGA consoles.
2011-11-01 04:11:27 +04:00
To facilitate more flexible debugging, we also add
console_suspend, a printk module parameter to control
it. Users could use console_suspend (usually
/sys/module/printk/parameters/console_suspend) to
turn on/off it dynamically.
2009-04-06 02:55:22 +04:00
2007-05-31 11:40:47 +04:00
noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
caches in the slab allocator. Saves per-node memory,
but will impact performance.
2006-12-07 07:32:16 +03:00
2005-10-23 23:57:11 +04:00
noalign [KNL,ARM]
2005-04-17 02:20:36 +04:00
noapic [SMP,APIC] Tells the kernel to not make use of any
IOAPICs that may be present in the system.
sched: Add 'autogroup' scheduling feature: automated per session task groups
A recurring complaint from CFS users is that parallel kbuild has
a negative impact on desktop interactivity. This patch
implements an idea from Linus, to automatically create task
groups. Currently, only per session autogroups are implemented,
but the patch leaves the way open for enhancement.
Implementation: each task's signal struct contains an inherited
pointer to a refcounted autogroup struct containing a task group
pointer, the default for all tasks pointing to the
init_task_group. When a task calls setsid(), a new task group
is created, the process is moved into the new task group, and a
reference to the preveious task group is dropped. Child
processes inherit this task group thereafter, and increase it's
refcount. When the last thread of a process exits, the
process's reference is dropped, such that when the last process
referencing an autogroup exits, the autogroup is destroyed.
At runqueue selection time, IFF a task has no cgroup assignment,
its current autogroup is used.
Autogroup bandwidth is controllable via setting it's nice level
through the proc filesystem:
cat /proc/<pid>/autogroup
Displays the task's group and the group's nice level.
echo <nice level> > /proc/<pid>/autogroup
Sets the task group's shares to the weight of nice <level> task.
Setting nice level is rate limited for !admin users due to the
abuse risk of task group locking.
The feature is enabled from boot by default if
CONFIG_SCHED_AUTOGROUP=y is selected, but can be disabled via
the boot option noautogroup, and can also be turned on/off on
the fly via:
echo [01] > /proc/sys/kernel/sched_autogroup_enabled
... which will automatically move tasks to/from the root task group.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Paul Turner <pjt@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
[ Removed the task_group_path() debug code, and fixed !EVENTFD build failure. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1290281700.28711.9.camel@maggy.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-30 16:18:03 +03:00
noautogroup Disable scheduler automatic task group creation.
2005-04-17 02:20:36 +04:00
nobats [PPC] Do not use BATs for mapping kernel lowmem
on "Classic" PPC cores.
nocache [ARM]
2005-10-23 23:57:11 +04:00
2009-04-06 02:55:22 +04:00
noclflush [BUGS=X86] Don't use the CLFLUSH instruction
2006-07-30 14:03:11 +04:00
nodelayacct [KNL] Disable per-task delay accounting
2005-04-17 02:20:36 +04:00
nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
2008-09-21 12:14:42 +04:00
nodsp [SH] Disable hardware DSP at boot time.
2009-04-14 12:33:43 +04:00
noefi [X86] Disable EFI runtime services support.
2008-01-30 15:32:11 +03:00
2005-04-17 02:20:36 +04:00
noexec [IA-64]
2009-04-14 12:33:43 +04:00
noexec [X86]
2008-04-12 12:28:25 +04:00
On X86-32 available only on PAE configured kernels.
2005-04-17 02:20:36 +04:00
noexec=on: enable non-executable mappings (default)
2008-04-12 12:28:25 +04:00
noexec=off: disable non-executable mappings
2012-09-21 23:43:13 +04:00
nosmap [X86]
Disable SMAP (Supervisor Mode Access Prevention)
even if it is supported by processor.
2011-05-12 03:51:05 +04:00
nosmep [X86]
2012-09-21 23:43:13 +04:00
Disable SMEP (Supervisor Mode Execution Prevention)
2011-05-12 03:51:05 +04:00
even if it is supported by processor.
2008-04-12 12:28:25 +04:00
noexec32 [X86-64]
This affects only 32-bit executables.
noexec32=on: enable non-executable mappings (default)
read doesn't imply executable mappings
noexec32=off: disable non-executable mappings
read implies executable mappings
2005-04-17 02:20:36 +04:00
2008-09-21 12:14:42 +04:00
nofpu [SH] Disable hardware FPU at boot time.
2007-07-31 11:37:59 +04:00
nofxsr [BUGS=X86-32] Disables x86 floating point extended
2006-03-23 13:59:34 +03:00
register save and restore. The kernel will only save
legacy floating-point registers on task switch.
2005-04-17 02:20:36 +04:00
2009-05-22 23:17:45 +04:00
noxsave [BUGS=X86] Disables x86 extended register state save
and restore using xsave. The kernel will fallback to
enabling legacy floating-point and sse state.
2014-05-29 22:12:31 +04:00
noxsaveopt [X86] Disables xsaveopt used in saving x86 extended
register states. The kernel will fall back to use
xsave to save the states. By using this parameter,
performance of saving the states is degraded because
xsave doesn't support modified optimization while
xsaveopt supports it on xsaveopt enabled systems.
noxsaves [X86] Disables xsaves and xrstors used in saving and
restoring x86 extended register state in compacted
form of xsave area. The kernel will fall back to use
xsaveopt and xrstor to save and restore the states
in standard form of xsave area. By using this
parameter, xsave area per process might occupy more
memory on xsaves enabled systems.
2012-09-07 01:58:52 +04:00
eagerfpu= [X86]
2012-09-10 21:32:32 +04:00
on enable eager fpu restore
2012-09-07 01:58:52 +04:00
off disable eager fpu restore
2012-09-10 21:32:32 +04:00
auto selects the default scheme, which automatically
enables eagerfpu restore for xsaveopt.
2012-09-07 01:58:52 +04:00
2009-03-31 16:55:44 +04:00
nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or
wfi(ARM) instruction doesn't work correctly and not to
use it. This is also useful when using JTAG debugger.
2005-10-23 23:57:11 +04:00
file capabilities: add no_file_caps switch (v4)
Add a no_file_caps boot option when file capabilities are
compiled into the kernel (CONFIG_SECURITY_FILE_CAPABILITIES=y).
This allows distributions to ship a kernel with file capabilities
compiled in, without forcing users to use (and understand and
trust) them.
When no_file_caps is specified at boot, then when a process executes
a file, any file capabilities stored with that file will not be
used in the calculation of the process' new capability sets.
This means that booting with the no_file_caps boot option will
not be the same as booting a kernel with file capabilities
compiled out - in particular a task with CAP_SETPCAP will not
have any chance of passing capabilities to another task (which
isn't "really" possible anyway, and which may soon by killed
altogether by David Howells in any case), and it will instead
be able to put new capabilities in its pI. However since fI
will always be empty and pI is masked with fI, it gains the
task nothing.
We also support the extra prctl options, setting securebits and
dropping capabilities from the per-process bounding set.
The other remaining difference is that killpriv, task_setscheduler,
setioprio, and setnice will continue to be hooked. That will
be noticable in the case where a root task changed its uid
while keeping some caps, and another task owned by the new uid
tries to change settings for the more privileged task.
Changelog:
Nov 05 2008: (v4) trivial port on top of always-start-\
with-clear-caps patch
Sep 23 2008: nixed file_caps_enabled when file caps are
not compiled in as it isn't used.
Document no_file_caps in kernel-parameters.txt.
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-06 01:08:52 +03:00
no_file_caps Tells the kernel not to honor file capabilities. The
only way then for a file to be executed with privilege
is to be setuid root or executed by root.
2005-04-17 02:20:36 +04:00
nohalt [IA-64] Tells the kernel not to use the power saving
function PAL_HALT_LIGHT when idle. This increases
power-consumption. On the positive side, it reduces
interrupt wake-up latency, which may improve performance
in certain environments such as networked servers or
real-time systems.
2014-06-14 00:30:35 +04:00
nohibernate [HIBERNATION] Disable hibernation and resume.
2007-02-16 12:28:03 +03:00
nohz= [KNL] Boottime enable/disable dynamic ticks
Valid arguments: on, off
Default: on
2013-04-12 18:45:34 +04:00
nohz_full= [KNL,BOOT]
In kernels built with CONFIG_NO_HZ_FULL=y, set
2012-12-18 20:32:19 +04:00
the specified list of CPUs whose tick will be stopped
2013-03-27 05:18:34 +04:00
whenever possible. The boot CPU will be forced outside
the range to maintain the timekeeping.
2013-03-27 02:47:24 +04:00
The CPUs in this range must also be included in the
rcu_nocbs= set.
2012-12-18 20:32:19 +04:00
2009-04-02 07:31:16 +04:00
noiotrap [SH] Disables trapped I/O port accesses.
2007-07-31 11:37:59 +04:00
noirqdebug [X86-32] Disables the code which attempts to detect and
2005-04-17 02:20:36 +04:00
disable unhandled interrupt sources.
2009-04-14 12:33:43 +04:00
no_timer_check [X86,APIC] Disables the code which tests for
2006-12-07 04:14:09 +03:00
broken timer IRQ sources.
2005-04-17 02:20:36 +04:00
noisapnp [ISAPNP] Disables ISA PnP code.
noinitrd [RAM] Tells the kernel not to load any configured
initial RAM disk.
2009-04-17 12:42:15 +04:00
nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
remapping.
2010-07-20 22:06:49 +04:00
[Deprecated - use intremap=off]
2009-04-17 12:42:15 +04:00
2005-04-17 02:20:36 +04:00
nointroute [IA-64]
2011-08-13 23:34:52 +04:00
nojitter [IA-64] Disables jitter checking for ITC timers.
2007-07-20 22:22:30 +04:00
2010-08-16 19:51:20 +04:00
no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
2010-10-14 13:22:51 +04:00
no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page
fault handling.
2011-07-11 23:28:19 +04:00
no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting.
steal time is computed, but won't influence scheduler
behaviour
2007-07-31 11:37:59 +04:00
nolapic [X86-32,APIC] Do not enable or use the local APIC.
2005-04-17 02:20:36 +04:00
2007-07-31 11:37:59 +04:00
nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
2007-03-22 11:11:21 +03:00
2005-04-17 02:20:36 +04:00
noltlbs [PPC] Do not use large page/tlb entries for kernel
lowmem mapping on PPC40x.
2006-02-22 03:57:55 +03:00
nomca [IA-64] Disable machine check abort handling
2007-07-31 11:37:59 +04:00
nomce [X86-32] Machine Check Exception
2006-04-01 03:36:09 +04:00
2007-10-13 01:04:06 +04:00
nomfgpt [X86-32] Disable Multi-Function General Purpose
Timer usage (for AMD Geode machines).
2011-10-13 23:14:27 +04:00
nonmi_ipi [X86] Disable using NMI IPIs during panic/reboot to
shutdown the other cpus. Instead use the REBOOT_VECTOR
irq.
2012-02-01 06:33:14 +04:00
nomodule Disable module load
2010-01-18 19:05:40 +03:00
nopat [X86] Disable PAT (page attribute table extension of
pagetables) support.
2009-04-06 02:55:22 +04:00
norandmaps Don't use address space randomization. Equivalent to
echo 0 > /proc/sys/kernel/randomize_va_space
2010-08-11 20:34:09 +04:00
noreplace-paravirt [X86,IA-64,PV_OPS] Don't patch paravirt_ops
2007-05-02 21:27:16 +04:00
2007-07-31 11:37:59 +04:00
noreplace-smp [X86-32,SMP] Don't replace SMP instructions
2007-05-02 21:27:13 +04:00
with UP alternatives
2014-05-12 07:25:20 +04:00
nordrand [X86] Disable kernel use of the RDRAND and
RDSEED instructions even if they are supported
by the processor. RDRAND and RDSEED are still
available to user space applications.
2011-08-01 01:02:19 +04:00
2005-10-23 23:57:11 +04:00
noresume [SWSUSP] Disables resume and restores original swap
space.
2005-04-17 02:20:36 +04:00
no-scroll [VGA] Disables scrollback.
This is required for the Braillex ib80-piezo Braille
reader made by F.H. Papenmeier (Germany).
nosbagart [IA-64]
2007-07-31 11:37:59 +04:00
nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support.
2006-03-23 13:59:34 +03:00
2007-08-16 11:34:22 +04:00
nosmp [SMP] Tells an SMP kernel to act as a UP kernel,
and disable the IO APIC. legacy for "maxcpus=0".
2005-04-17 02:20:36 +04:00
2007-07-16 10:41:05 +04:00
nosoftlockup [KNL] Disable the soft-lockup detector.
2005-04-17 02:20:36 +04:00
nosync [HW,M68K] Disables sync negotiation for all devices.
2007-07-31 11:37:59 +04:00
notsc [BUGS=X86-32] Disable Time Stamp Counter
2005-04-17 02:20:36 +04:00
nousb [USB] Disable the USB subsystem
2011-01-03 02:02:42 +03:00
nowatchdog [KNL] Disable the lockup detector (NMI watchdog).
2010-05-08 01:11:44 +04:00
2005-04-17 02:20:36 +04:00
nowb [ARM]
2005-10-23 23:57:11 +04:00
2009-04-17 12:42:12 +04:00
nox2apic [X86-64,APIC] Do not enable x2APIC mode.
2012-11-13 23:32:38 +04:00
cpu0_hotplug [X86] Turn on CPU0 hotplug feature when
CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off.
Some features depend on CPU0. Known dependencies are:
1. Resume from suspend/hibernate depends on CPU0.
Suspend/hibernate will fail if CPU0 is offline and you
need to online CPU0 before suspend/hibernate.
2. PIC interrupts also depend on CPU0. CPU0 can't be
removed if a PIC interrupt is detected.
It's said poweroff/reboot may depend on CPU0 on some
machines although I haven't seen such issues so far
after CPU0 is offline on a few tested machines.
If the dependencies are under your control, you can
turn on cpu0_hotplug.
2011-08-13 23:34:52 +04:00
nptcg= [IA-64] Override max number of concurrent global TLB
2008-03-14 23:57:08 +03:00
purges which is reported from either PAL_VM_SUMMARY or
SAL PALO.
2010-02-10 12:20:37 +03:00
nr_cpus= [SMP] Maximum number of processors that an SMP kernel
could support. nr_cpus=n : n >= 1 limits the kernel to
supporting 'n' processors. Later in runtime you can not
use hotplug cpu feature to put more cpu back to online.
just like you compile the kernel NR_CPUS=n
2009-04-06 02:55:22 +04:00
nr_uarts= [SERIAL] maximum number of UARTs to be registered.
2012-11-22 15:16:36 +04:00
numa_balancing= [KNL,X86] Enable or disable automatic NUMA balancing.
Allowed values are enable and disable
2007-07-16 10:38:01 +04:00
numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
one of ['zone', 'node', 'default'] can be specified
This can be set from sysctl after boot.
See Documentation/sysctl/vm.txt for details.
2009-01-07 01:42:44 +03:00
ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
See Documentation/debugging-via-ohci1394.txt for more
info.
2008-04-29 11:59:53 +04:00
olpc_ec_timeout= [OLPC] ms delay when issuing EC commands
Rather than timing out after 20 ms if an EC
command is not properly ACKed, override the length
of the timeout. We have interrupts disabled while
waiting for the ACK, so if this is set too high
interrupts *may* be lost!
2009-12-12 03:16:32 +03:00
omap_mux= [OMAP] Override bootloader pin multiplexing.
Format: <mux_mode0.mode_name=value>...
For example, to override I2C bus2:
omap_mux=i2c2_scl.i2c2_scl=0x100,i2c2_sda.i2c2_sda=0x100
2005-04-17 02:20:36 +04:00
oprofile.timer= [HW]
Use timer interrupt instead of performance counters
2009-05-06 14:10:23 +04:00
oprofile.cpu_type= Force an oprofile cpu type
This might be useful if you have an older oprofile
userland or if you want common events.
2009-06-23 13:48:14 +04:00
Format: { arch_perfmon }
arch_perfmon: [X86] Force use of architectural
2009-05-06 14:10:23 +04:00
perfmon on Intel CPUs instead of the
CPU specific event set.
2011-10-11 21:39:16 +04:00
timer: [X86] Force use of architectural NMI
timer mode (see also oprofile.timer
for generic hr timer mode)
2011-11-25 23:03:05 +04:00
[s390] Force legacy basic mode sampling
(report cpu_type "timer")
2009-04-27 19:44:11 +04:00
2011-04-05 02:02:24 +04:00
oops=panic Always panic on oopses. Default is to just kill the
process, but there is a small probability of
deadlocking the machine.
2011-03-23 02:34:04 +03:00
This will also cause panics on machine check exceptions.
Useful together with panic=30 to trigger a reboot.
2010-06-08 04:10:38 +04:00
OSS [HW,OSS]
See Documentation/sound/oss/oss-parameters.txt
2011-04-05 02:02:24 +04:00
panic= [KNL] Kernel behaviour on panic: delay <timeout>
2011-07-27 03:08:52 +04:00
timeout > 0: seconds before rebooting
timeout = 0: wait forever
timeout < 0: reboot immediately
2005-04-17 02:20:36 +04:00
Format: <timeout>
2014-06-07 01:37:07 +04:00
crash_kexec_post_notifiers
Run kdump after running panic-notifiers and dumping
kmsg. This only for the users who doubt kdump always
succeeds in any situation.
Note that this also increases risks of kdump failure,
because some panic notifiers can make the crashed
kernel more unstable.
2005-04-17 02:20:36 +04:00
parkbd.port= [HW] Parallel port number the keyboard adapter is
connected to, default is 0.
Format: <parport#>
parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
0 for XT, 1 for AT (default is AT).
2005-10-23 23:57:11 +04:00
Format: <mode>
parport= [HW,PPT] Specify parallel ports. 0 disables.
Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
Use 'auto' to force the driver to use any
IRQ/DMA settings detected (the default is to
ignore detected IRQ/DMA settings because of
possible conflicts). You can specify the base
address, IRQ, and DMA settings; IRQ and DMA
should be numbers, or 'auto' (for using detected
settings on that particular port), or 'nofifo'
(to avoid using a FIFO even if it is detected).
Parallel ports are assigned in the order they
are specified on the command line, starting
with parport0.
parport_init_mode= [HW,PPT]
Configure VIA parallel port to operate in
a specific mode. This is necessary on Pegasos
computer where firmware has no options for setting
up parallel port mode and sets it to spp.
Currently this function knows 686a and 8231 chips.
2005-04-17 02:20:36 +04:00
Format: [spp|ps2|epp|ecp|ecpepp]
2006-03-23 14:00:57 +03:00
pause_on_oops=
Halt all CPUs after the first oops has been printed for
the specified number of seconds. This is to be used if
your oopses keep scrolling off the screen.
2005-04-17 02:20:36 +04:00
pcbit= [HW,ISDN]
pcd. [PARIDE]
See header of drivers/block/paride/pcd.c.
2008-11-14 00:33:24 +03:00
See also Documentation/blockdev/paride.txt.
2005-04-17 02:20:36 +04:00
2005-10-23 23:57:11 +04:00
pci=option[,option...] [PCI] various PCI subsystem options:
2009-01-14 20:04:36 +03:00
earlydump [X86] dump PCI config space before the kernel
changes anything
2008-08-22 11:53:39 +04:00
off [X86] don't probe for the PCI bus
2007-07-31 11:37:59 +04:00
bios [X86-32] force use of PCI BIOS, don't access
2005-10-23 23:57:11 +04:00
the hardware directly. Use this if your machine
has a non-standard PCI host bridge.
2007-07-31 11:37:59 +04:00
nobios [X86-32] disallow use of PCI BIOS, only direct
2005-10-23 23:57:11 +04:00
hardware access methods are allowed. Use this
if you experience crashes upon bootup and you
suspect they are caused by the BIOS.
2008-08-22 11:53:39 +04:00
conf1 [X86] Force use of PCI Configuration
2005-10-23 23:57:11 +04:00
Mechanism 1.
2008-08-22 11:53:39 +04:00
conf2 [X86] Force use of PCI Configuration
2005-10-23 23:57:11 +04:00
Mechanism 2.
2007-10-06 00:17:58 +04:00
noaer [PCIE] If the PCIEAER kernel config parameter is
enabled, this kernel boot option can be used to
disable the use of PCIE advanced error reporting.
2007-10-12 00:57:27 +04:00
nodomains [PCI] Disable support for multiple PCI
root domains (aka PCI segments, in ACPI-speak).
2009-04-14 12:33:43 +04:00
nommconf [X86] Disable use of MMCONFIG for PCI
2006-02-16 02:17:43 +03:00
Configuration
2009-06-07 18:15:16 +04:00
check_enable_amd_mmconf [X86] check for and enable
properly configured MMIO access to PCI
config space on AMD family 10h CPU
2006-03-06 08:33:34 +03:00
nomsi [MSI] If the PCI_MSI kernel config parameter is
enabled, this kernel boot option can be used to
disable the use of MSI interrupts system-wide.
2008-06-11 18:35:14 +04:00
noioapicquirk [APIC] Disable all boot interrupt quirks.
Safety option to keep boot IRQs enabled. This
should never be necessary.
2008-06-11 18:35:15 +04:00
ioapicreroute [APIC] Enable rerouting of boot IRQs to the
primary IO-APIC for bridges that cannot disable
boot IRQs. This fixes a source of spurious IRQs
when the system masks IRQs.
2008-07-15 15:48:55 +04:00
noioapicreroute [APIC] Disable workaround that uses the
boot IRQ equivalent of an IRQ that connects to
a chipset where boot IRQs cannot be disabled.
The opposite of ioapicreroute.
2007-07-31 11:37:59 +04:00
biosirq [X86-32] Use PCI BIOS calls to get the interrupt
2005-10-23 23:57:11 +04:00
routing table. These calls are known to be buggy
on several machines and they hang the machine
when used, but on other computers it's the only
way to get the interrupt routing table. Try
this option if the kernel is unable to allocate
IRQs or discover secondary PCI buses on your
motherboard.
2008-08-22 11:53:39 +04:00
rom [X86] Assign address space to expansion ROMs.
2005-10-23 23:57:11 +04:00
Use with caution as certain devices share
address decoders between ROMs and other
resources.
2008-08-22 11:53:39 +04:00
norom [X86] Do not assign address space to
2008-05-13 00:57:46 +04:00
expansion ROMs that do not already have
BIOS assigned address ranges.
2010-05-12 22:14:32 +04:00
nobar [X86] Do not assign address space to the
BARs that weren't assigned by the BIOS.
2008-08-22 11:53:39 +04:00
irqmask=0xMMMM [X86] Set a bit mask of IRQs allowed to be
2005-10-23 23:57:11 +04:00
assigned automatically to PCI devices. You can
make the kernel exclude IRQs of your ISA cards
this way.
2008-08-22 11:53:39 +04:00
pirqaddr=0xAAAAA [X86] Specify the physical address
2005-10-23 23:57:11 +04:00
of the PIRQ table (normally generated
by the BIOS) if it is outside the
F0000h-100000h range.
2008-08-22 11:53:39 +04:00
lastbus=N [X86] Scan all buses thru bus #N. Can be
2005-10-23 23:57:11 +04:00
useful if the kernel is unable to find your
secondary buses and you want to tell it
explicitly which ones they are.
2008-08-22 11:53:39 +04:00
assign-busses [X86] Always assign all PCI bus
2005-10-23 23:57:11 +04:00
numbers ourselves, overriding
whatever the firmware may have done.
2008-08-22 11:53:39 +04:00
usepirqmask [X86] Honor the possible IRQ mask stored
2005-10-23 23:57:11 +04:00
in the BIOS $PIR table. This is needed on
some systems with broken BIOSes, notably
some HP Pavilion N5400 and Omnibook XE3
notebooks. This will have no effect if ACPI
IRQ routing is enabled.
2008-08-22 11:53:39 +04:00
noacpi [X86] Do not use ACPI for IRQ routing
2005-10-23 23:57:11 +04:00
or for PCI scanning.
2010-02-23 20:24:41 +03:00
use_crs [X86] Use PCI host bridge window information
from ACPI. On BIOSes from 2008 or later, this
is enabled by default. If you need to use this,
please report a bug.
nocrs [X86] Ignore PCI host bridge windows from ACPI.
If you need to use this, please report a bug.
2005-10-23 23:57:11 +04:00
routeirq Do IRQ routing for all PCI devices.
This is normally done in pci_enable_device(),
so this option is a temporary workaround
for broken drivers that don't call it.
2008-03-27 11:31:18 +03:00
skip_isa_align [X86] do not align io start addr, so can
handle more pci cards
2005-10-23 23:57:11 +04:00
firmware [ARM] Do not re-enumerate the bus but instead
just use the configuration from the
bootloader. This is currently used on
IXP2000 systems where the bus has to be
configured a certain way for adjunct CPUs.
2006-09-26 12:52:41 +04:00
noearly [X86] Don't do any early type 1 scanning.
This might help on some broken boards which
machine check when some devices' config space
is read. But various workarounds are disabled
and some IOMMU drivers will not work.
PCI: optionally sort device lists breadth-first
Problem:
New Dell PowerEdge servers have 2 embedded ethernet ports, which are
labeled NIC1 and NIC2 on the chassis, in the BIOS setup screens, and
in the printed documentation. Assuming no other add-in ethernet ports
in the system, Linux 2.4 kernels name these eth0 and eth1
respectively. Many people have come to expect this naming. Linux 2.6
kernels name these eth1 and eth0 respectively (backwards from
expectations). I also have reports that various Sun and HP servers
have similar behavior.
Root cause:
Linux 2.4 kernels walk the pci_devices list, which happens to be
sorted in breadth-first order (or pcbios_find_device order on i386,
which most often is breadth-first also). 2.6 kernels have both the
pci_devices list and the pci_bus_type.klist_devices list, the latter
is what is walked at driver load time to match the pci_id tables; this
klist happens to be in depth-first order.
On systems where, for physical routing reasons, NIC1 appears on a
lower bus number than NIC2, but NIC2's bridge is discovered first in
the depth-first ordering, NIC2 will be discovered before NIC1. If the
list were sorted breadth-first, NIC1 would be discovered before NIC2.
A PowerEdge 1955 system has the following topology which easily
exhibits the difference between depth-first and breadth-first device
lists.
-[0000:00]-+-00.0 Intel Corporation 5000P Chipset Memory Controller Hub
+-02.0-[0000:03-08]--+-00.0-[0000:04-07]--+-00.0-[0000:05-06]----00.0-[0000:06]----00.0 Broadcom Corporation NetXtreme II BCM5708S Gigabit Ethernet (labeled NIC2, 2.4 kernel name eth1, 2.6 kernel name eth0)
+-1c.0-[0000:01-02]----00.0-[0000:02]----00.0 Broadcom Corporation NetXtreme II BCM5708S Gigabit Ethernet (labeled NIC1, 2.4 kernel name eth0, 2.6 kernel name eth1)
Other factors, such as device driver load order and the presence of
PCI slots at various points in the bus hierarchy further complicate
this problem; I'm not trying to solve those here, just restore the
device order, and thus basic behavior, that 2.4 kernels had.
Solution:
The solution can come in multiple steps.
Suggested fix #1: kernel
Patch below optionally sorts the two device lists into breadth-first
ordering to maintain compatibility with 2.4 kernels. It adds two new
command line options:
pci=bfsort
pci=nobfsort
to force the sort order, or not, as you wish. It also adds DMI checks
for the specific Dell systems which exhibit "backwards" ordering, to
make them "right".
Suggested fix #2: udev rules from userland
Many people also have the expectation that embedded NICs are always
discovered before add-in NICs (which this patch does not try to do).
Using the PCI IRQ Routing Table provided by system BIOS, it's easy to
determine which PCI devices are embedded, or if add-in, which PCI slot
they're in. I'm working on a tool that would allow udev to name
ethernet devices in ascending embedded, slot 1 .. slot N order,
subsort by PCI bus/dev/fn breadth-first. It'll be possible to use it
independent of udev as well for those distributions that don't use
udev in their installers.
Suggested fix #3: system board routing rules
One can constrain the system board layout to put NIC1 ahead of NIC2
regardless of breadth-first or depth-first discovery order. This adds
a significant level of complexity to board routing, and may not be
possible in all instances (witness the above systems from several
major manufacturers). I don't want to encourage this particular train
of thought too far, at the expense of not doing #1 or #2 above.
Feedback appreciated. Patch tested on a Dell PowerEdge 1955 blade
with 2.6.18.
You'll also note I took some liberty and temporarily break the klist
abstraction to simplify and speed up the sort algorithm. I think
that's both safe and appropriate in this instance.
Signed-off-by: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-30 00:23:23 +04:00
bfsort Sort PCI devices into breadth-first order.
This sorting is done to get a device
order compatible with older (<= 2.4) kernels.
nobfsort Don't sort PCI devices into breadth-first order.
2013-01-30 05:40:52 +04:00
pcie_bus_tune_off Disable PCIe MPS (Max Payload Size)
tuning and use the BIOS-configured MPS defaults.
pcie_bus_safe Set every device's MPS to the largest value
supported by all devices below the root complex.
pcie_bus_perf Set device MPS to the largest allowable MPS
based on its parent bus. Also set MRRS (Max
Read Request Size) to the largest supported
value (no larger than the MPS that the device
or bus can support) for best performance.
pcie_bus_peer2peer Set every device's MPS to 128B, which
every device is guaranteed to support. This
configuration allows peer-to-peer DMA between
any pair of devices, possibly at the cost of
reduced performance. This also guarantees
that hot-added devices will work.
2007-02-06 03:36:06 +03:00
cbiosize=nn[KMG] The fixed amount of bus space which is
reserved for the CardBus bridge's IO window.
The default value is 256 bytes.
cbmemsize=nn[KMG] The fixed amount of bus space which is
reserved for the CardBus bridge's memory
window. The default value is 64 megabytes.
2009-03-16 11:13:39 +03:00
resource_alignment=
Format:
[<order of align>@][<domain>:]<bus>:<slot>.<func>[; ...]
Specifies alignment and device to reassign
aligned memory resources.
If <order of align> is not specified,
PAGE_SIZE is used as alignment.
PCI-PCI bridge can be specified, if resource
windows need to be expanded.
2009-04-23 02:52:09 +04:00
ecrc= Enable/disable PCIe ECRC (transaction layer
end-to-end CRC checking).
bios: Use BIOS/firmware settings. This is the
the default.
off: Turn ECRC off
on: Turn ECRC on.
2013-01-23 16:29:06 +04:00
hpiosize=nn[KMG] The fixed amount of bus space which is
reserved for hotplug bridge's IO window.
Default size is 256 bytes.
hpmemsize=nn[KMG] The fixed amount of bus space which is
reserved for hotplug bridge's memory window.
Default size is 2 megabytes.
2012-02-24 07:23:30 +04:00
realloc= Enable/disable reallocating PCI bridge resources
if allocations done by BIOS are too small to
accommodate resources required by all child
devices.
off: Turn realloc off
on: Turn realloc on
realloc same as realloc=on
2012-03-01 03:06:33 +04:00
noari do not use PCIe ARI.
2012-05-01 01:21:02 +04:00
pcie_scan_all Scan all possible PCIe devices. Otherwise we
only look for one device below a PCIe downstream
port.
PCI: optionally sort device lists breadth-first
Problem:
New Dell PowerEdge servers have 2 embedded ethernet ports, which are
labeled NIC1 and NIC2 on the chassis, in the BIOS setup screens, and
in the printed documentation. Assuming no other add-in ethernet ports
in the system, Linux 2.4 kernels name these eth0 and eth1
respectively. Many people have come to expect this naming. Linux 2.6
kernels name these eth1 and eth0 respectively (backwards from
expectations). I also have reports that various Sun and HP servers
have similar behavior.
Root cause:
Linux 2.4 kernels walk the pci_devices list, which happens to be
sorted in breadth-first order (or pcbios_find_device order on i386,
which most often is breadth-first also). 2.6 kernels have both the
pci_devices list and the pci_bus_type.klist_devices list, the latter
is what is walked at driver load time to match the pci_id tables; this
klist happens to be in depth-first order.
On systems where, for physical routing reasons, NIC1 appears on a
lower bus number than NIC2, but NIC2's bridge is discovered first in
the depth-first ordering, NIC2 will be discovered before NIC1. If the
list were sorted breadth-first, NIC1 would be discovered before NIC2.
A PowerEdge 1955 system has the following topology which easily
exhibits the difference between depth-first and breadth-first device
lists.
-[0000:00]-+-00.0 Intel Corporation 5000P Chipset Memory Controller Hub
+-02.0-[0000:03-08]--+-00.0-[0000:04-07]--+-00.0-[0000:05-06]----00.0-[0000:06]----00.0 Broadcom Corporation NetXtreme II BCM5708S Gigabit Ethernet (labeled NIC2, 2.4 kernel name eth1, 2.6 kernel name eth0)
+-1c.0-[0000:01-02]----00.0-[0000:02]----00.0 Broadcom Corporation NetXtreme II BCM5708S Gigabit Ethernet (labeled NIC1, 2.4 kernel name eth0, 2.6 kernel name eth1)
Other factors, such as device driver load order and the presence of
PCI slots at various points in the bus hierarchy further complicate
this problem; I'm not trying to solve those here, just restore the
device order, and thus basic behavior, that 2.4 kernels had.
Solution:
The solution can come in multiple steps.
Suggested fix #1: kernel
Patch below optionally sorts the two device lists into breadth-first
ordering to maintain compatibility with 2.4 kernels. It adds two new
command line options:
pci=bfsort
pci=nobfsort
to force the sort order, or not, as you wish. It also adds DMI checks
for the specific Dell systems which exhibit "backwards" ordering, to
make them "right".
Suggested fix #2: udev rules from userland
Many people also have the expectation that embedded NICs are always
discovered before add-in NICs (which this patch does not try to do).
Using the PCI IRQ Routing Table provided by system BIOS, it's easy to
determine which PCI devices are embedded, or if add-in, which PCI slot
they're in. I'm working on a tool that would allow udev to name
ethernet devices in ascending embedded, slot 1 .. slot N order,
subsort by PCI bus/dev/fn breadth-first. It'll be possible to use it
independent of udev as well for those distributions that don't use
udev in their installers.
Suggested fix #3: system board routing rules
One can constrain the system board layout to put NIC1 ahead of NIC2
regardless of breadth-first or depth-first discovery order. This adds
a significant level of complexity to board routing, and may not be
possible in all instances (witness the above systems from several
major manufacturers). I don't want to encourage this particular train
of thought too far, at the expense of not doing #1 or #2 above.
Feedback appreciated. Patch tested on a Dell PowerEdge 1955 blade
with 2.6.18.
You'll also note I took some liberty and temporarily break the klist
abstraction to simplify and speed up the sort algorithm. I think
that's both safe and appropriate in this instance.
Signed-off-by: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-30 00:23:23 +04:00
2008-09-25 04:40:34 +04:00
pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
Management.
off Disable ASPM.
force Enable ASPM even on devices that claim not to support it.
WARNING: Forcing ASPM on may cause system lockups.
2012-02-02 20:09:22 +04:00
pcie_hp= [PCIE] PCI Express Hotplug driver options:
nomsi Do not use MSI for PCI Express Native Hotplug (this
makes all PCIe ports use INTx for hotplug services).
2010-08-21 03:51:44 +04:00
pcie_ports= [PCIE] PCIe ports handling:
PCI: PCIe: Ask BIOS for control of all native services at once
After commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable
ASPM if the platform won't provide _OSC control for PCIe) control of
the PCIe Capability Structure is unconditionally requested by
acpi_pci_root_add(), which in principle may cause problems to
happen in two ways. First, the BIOS may refuse to give control of
the PCIe Capability Structure if it is not asked for any of the
_OSC features depending on it at the same time. Second, the BIOS may
assume that control of the _OSC features depending on the PCIe
Capability Structure will be requested in the future and may behave
incorrectly if that doesn't happen. For this reason, control of
the PCIe Capability Structure should always be requested along with
control of any other _OSC features that may depend on it (ie. PCIe
native PME, PCIe native hot-plug, PCIe AER).
Rework the PCIe port driver so that (1) it checks which native PCIe
port services can be enabled, according to the BIOS, and (2) it
requests control of all these services simultaneously. In
particular, this causes pcie_portdrv_probe() to fail if the BIOS
refuses to grant control of the PCIe Capability Structure, which
means that no native PCIe port services can be enabled for the PCIe
Root Complex the given port belongs to. If that happens, ASPM is
disabled to avoid problems with mishandling it by the part of the
PCIe hierarchy for which control of the PCIe Capability Structure
has not been received.
Make it possible to override this behavior using 'pcie_ports=native'
(use the PCIe native services regardless of the BIOS response to the
control request), or 'pcie_ports=compat' (do not use the PCIe native
services at all).
Accordingly, rework the existing PCIe port service drivers so that
they don't request control of the services directly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-22 00:02:38 +04:00
auto Ask the BIOS whether or not to use native PCIe services
associated with PCIe ports (PME, hot-plug, AER). Use
them only if that is allowed by the BIOS.
native Use native PCIe services associated with PCIe ports
unconditionally.
2010-08-21 03:51:44 +04:00
compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
ports driver.
2010-02-18 01:39:08 +03:00
pcie_pme= [PCIE,PM] Native PCIe PME signaling options:
2010-02-18 01:40:07 +03:00
nomsi Do not use MSI for native PCIe PME signaling (this makes
PCI: PCIe: Ask BIOS for control of all native services at once
After commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable
ASPM if the platform won't provide _OSC control for PCIe) control of
the PCIe Capability Structure is unconditionally requested by
acpi_pci_root_add(), which in principle may cause problems to
happen in two ways. First, the BIOS may refuse to give control of
the PCIe Capability Structure if it is not asked for any of the
_OSC features depending on it at the same time. Second, the BIOS may
assume that control of the _OSC features depending on the PCIe
Capability Structure will be requested in the future and may behave
incorrectly if that doesn't happen. For this reason, control of
the PCIe Capability Structure should always be requested along with
control of any other _OSC features that may depend on it (ie. PCIe
native PME, PCIe native hot-plug, PCIe AER).
Rework the PCIe port driver so that (1) it checks which native PCIe
port services can be enabled, according to the BIOS, and (2) it
requests control of all these services simultaneously. In
particular, this causes pcie_portdrv_probe() to fail if the BIOS
refuses to grant control of the PCIe Capability Structure, which
means that no native PCIe port services can be enabled for the PCIe
Root Complex the given port belongs to. If that happens, ASPM is
disabled to avoid problems with mishandling it by the part of the
PCIe hierarchy for which control of the PCIe Capability Structure
has not been received.
Make it possible to override this behavior using 'pcie_ports=native'
(use the PCIe native services regardless of the BIOS response to the
control request), or 'pcie_ports=compat' (do not use the PCIe native
services at all).
Accordingly, rework the existing PCIe port service drivers so that
they don't request control of the services directly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-22 00:02:38 +04:00
all PCIe root ports use INTx for all services).
2010-02-18 01:39:08 +03:00
2005-04-17 02:20:36 +04:00
pcmv= [HW,PCMCIA] BadgePAD 4
2014-03-28 09:20:21 +04:00
pd_ignore_unused
[PM]
Keep all power-domains already enabled by bootloader on,
even if no driver has claimed them. This is useful
for debug and development, but should not be
needed on a platform with proper driver support.
2005-04-17 02:20:36 +04:00
pd. [PARIDE]
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/paride.txt.
2005-04-17 02:20:36 +04:00
pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
boot time.
Format: { 0 | 1 }
See arch/parisc/kernel/pdc_chassis.c
2009-08-14 10:00:50 +04:00
percpu_alloc= Select which percpu first chunk allocator to use.
2009-08-14 10:00:53 +04:00
Currently supported values are "embed" and "page".
Archs may support subset or none of the selections.
See comments in mm/percpu.c for details on each
allocator. This parameter is primarily for debugging
and performance comparison.
2009-06-22 06:56:24 +04:00
2005-04-17 02:20:36 +04:00
pf. [PARIDE]
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/paride.txt.
2005-04-17 02:20:36 +04:00
pg. [PARIDE]
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/paride.txt.
2005-04-17 02:20:36 +04:00
pirq= [SMP,APIC] Manual mp-table setup
2008-10-20 20:32:21 +04:00
See Documentation/x86/i386/IO-APIC.txt.
2005-04-17 02:20:36 +04:00
plip= [PPT,NET] Parallel port network link
Format: { parport<nr> | timid | 0 }
See also Documentation/parport.txt.
2011-08-13 23:34:52 +04:00
pmtmr= [X86] Manual setup of pmtmr I/O Port.
2008-07-12 07:33:30 +04:00
Override pmtimer IOPort with a hex value.
e.g. pmtmr=0x508
2011-08-11 22:14:05 +04:00
pnp.debug=1 [PNP]
Enable PNP debug messages (depends on the
CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
via /sys/module/pnp/parameters/debug. We always show
current resource usage; turning this on also shows
possible settings and some assignment information.
2008-08-20 02:53:41 +04:00
2005-04-17 02:20:36 +04:00
pnpacpi= [ACPI]
{ off }
pnpbios= [ISAPNP]
{ on | off | curr | res | no-curr | no-res }
pnp_reserve_irq=
[ISAPNP] Exclude IRQs for the autoconfiguration
pnp_reserve_dma=
[ISAPNP] Exclude DMAs for the autoconfiguration
pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
2005-10-23 23:57:11 +04:00
Ranges are in pairs (I/O port base and size).
2005-04-17 02:20:36 +04:00
pnp_reserve_mem=
2005-10-23 23:57:11 +04:00
[ISAPNP] Exclude memory regions for the
autoconfiguration.
2005-04-17 02:20:36 +04:00
Ranges are in pairs (memory base and size).
2009-04-18 05:30:28 +04:00
ports= [IP_VS_FTP] IPVS ftp helper module
Default is 21.
Up to 8 (IP_VS_APP_MAX_PORTS) ports
may be specified.
Format: <port>,<port>....
2007-07-16 10:40:10 +04:00
print-fatal-signals=
[KNL] debug: print fatal signals
2009-11-08 18:46:42 +03:00
If enabled, warn about various signal handling
related application anomalies: too many signals,
too many POSIX.1 timers, fatal signals causing a
coredump - etc.
If you hit the warning due to signal overflow,
you might want to try "ulimit -i unlimited".
2007-07-16 10:40:10 +04:00
default: off.
2012-03-06 02:59:10 +04:00
printk.always_kmsg_dump=
Trigger kmsg_dump for cases other than kernel oops or
panics
Format: <bool> (1/Y/y=enable, 0/N/n=disable)
default: disabled
2007-07-16 10:40:25 +04:00
printk.time= Show timing data prefixed to each printk message line
Format: <bool> (1/Y/y=enable, 0/N/n=disable)
2009-04-06 02:55:22 +04:00
processor.max_cstate= [HW,ACPI]
Limit processor to maximum C-state
max_cstate=9 overrides any DMI blacklist limit.
processor.nocst [HW,ACPI]
Ignore the _CST method to determine C-states,
instead using the legacy FADT method
2005-04-17 02:20:36 +04:00
profile= [KNL] Enable kernel profiling via /proc/profile
2005-10-23 23:57:11 +04:00
Format: [schedule,]<number>
Param: "schedule" - profile schedule points.
Param: <number> - step/bucket size as a power of 2 for
statistical time based profiling.
2007-10-24 20:23:50 +04:00
Param: "sleep" - profile D-state sleeping (millisecs).
Requires CONFIG_SCHEDSTATS
2007-10-20 05:08:22 +04:00
Param: "kvm" - profile VM exits.
2005-04-17 02:20:36 +04:00
prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
before loading.
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/ramdisk.txt.
2005-04-17 02:20:36 +04:00
2005-10-23 23:57:11 +04:00
psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
probe for; one of (bare|imps|exps|lifebook|any).
2005-04-17 02:20:36 +04:00
psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
per second.
2005-10-23 23:57:11 +04:00
psmouse.resetafter= [HW,MOUSE]
Try to reset the device after so many bad packets
2005-04-17 02:20:36 +04:00
(0 = never).
psmouse.resolution=
[HW,MOUSE] Set desired mouse resolution, in dpi.
psmouse.smartscroll=
2005-10-23 23:57:11 +04:00
[HW,MOUSE] Controls Logitech smartscroll autorepeat.
2005-04-17 02:20:36 +04:00
0 = disabled, 1 = enabled (default).
2011-07-22 00:57:55 +04:00
pstore.backend= Specify the name of the pstore backend to use
2005-04-17 02:20:36 +04:00
pt. [PARIDE]
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/paride.txt.
2005-04-17 02:20:36 +04:00
2007-08-15 14:25:38 +04:00
pty.legacy_count=
[KNL] Number of legacy pty's. Overwrites compiled-in
default number.
2006-09-29 13:01:02 +04:00
quiet [KNL] Disable most log messages
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
r128= [HW,DRM]
raid= [HW,RAID]
See Documentation/md.txt.
2005-10-23 23:57:11 +04:00
ramdisk_blocksize= [RAM]
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/ramdisk.txt.
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
2008-11-14 00:33:24 +03:00
See Documentation/blockdev/ramdisk.txt.
2005-04-17 02:20:36 +04:00
2013-10-09 07:23:47 +04:00
rcu_nocbs= [KNL]
2012-08-20 08:35:53 +04:00
In kernels built with CONFIG_RCU_NOCB_CPU=y, set
the specified list of CPUs to be no-callback CPUs.
Invocation of these CPUs' RCU callbacks will
rcu: Distinguish "rcuo" kthreads by RCU flavor
Currently, the per-no-CBs-CPU kthreads are named "rcuo" followed by
the CPU number, for example, "rcuo". This is problematic given that
there are either two or three RCU flavors, each of which gets a per-CPU
kthread with exactly the same name. This commit therefore introduces
a one-letter abbreviation for each RCU flavor, namely 'b' for RCU-bh,
'p' for RCU-preempt, and 's' for RCU-sched. This abbreviation is used
to distinguish the "rcuo" kthreads, for example, for CPU 0 we would have
"rcuob/0", "rcuop/0", and "rcuos/0".
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
2012-12-03 20:16:28 +04:00
be offloaded to "rcuox/N" kthreads created for
that purpose, where "x" is "b" for RCU-bh, "p"
for RCU-preempt, and "s" for RCU-sched, and "N"
is the CPU number. This reduces OS jitter on the
2012-08-20 08:35:53 +04:00
offloaded CPUs, which can be useful for HPC and
real-time workloads. It can also improve energy
efficiency for asymmetric multiprocessors.
2013-10-09 07:23:47 +04:00
rcu_nocb_poll [KNL]
2012-08-20 08:35:53 +04:00
Rather than requiring that offloaded CPUs
(specified by rcu_nocbs= above) explicitly
awaken the corresponding "rcuoN" kthreads,
make these kthreads poll for callbacks.
This improves the real-time response for the
offloaded CPUs by relieving them of the need to
wake up the corresponding kthread, but degrades
energy efficiency by requiring that the kthreads
periodically wake up to do the polling.
2013-10-09 07:23:47 +04:00
rcutree.blimit= [KNL]
2013-10-27 20:44:03 +04:00
Set maximum number of finished RCU callbacks to
process in one batch.
2006-03-08 08:55:33 +03:00
2013-10-09 07:23:47 +04:00
rcutree.rcu_fanout_leaf= [KNL]
2012-04-24 02:52:53 +04:00
Increase the number of CPUs assigned to each
leaf rcu_node structure. Useful for very large
systems.
2014-06-21 03:49:01 +04:00
rcutree.jiffies_till_sched_qs= [KNL]
Set required age in jiffies for a
given grace period before RCU starts
soliciting quiescent-state help from
rcu_note_context_switch().
2013-10-09 07:23:47 +04:00
rcutree.jiffies_till_first_fqs= [KNL]
2012-12-28 23:30:36 +04:00
Set delay from grace-period initialization to
first attempt to force quiescent states.
Units are jiffies, minimum value is zero,
and maximum value is HZ.
2013-10-09 07:23:47 +04:00
rcutree.jiffies_till_next_fqs= [KNL]
2012-12-28 23:30:36 +04:00
Set delay between subsequent attempts to force
quiescent states. Units are jiffies, minimum
value is one, and maximum value is HZ.
rcu: Parallelize and economize NOCB kthread wakeups
An 80-CPU system with a context-switch-heavy workload can require so
many NOCB kthread wakeups that the RCU grace-period kthreads spend several
tens of percent of a CPU just awakening things. This clearly will not
scale well: If you add enough CPUs, the RCU grace-period kthreads would
get behind, increasing grace-period latency.
To avoid this problem, this commit divides the NOCB kthreads into leaders
and followers, where the grace-period kthreads awaken the leaders each of
whom in turn awakens its followers. By default, the number of groups of
kthreads is the square root of the number of CPUs, but this default may
be overridden using the rcutree.rcu_nocb_leader_stride boot parameter.
This reduces the number of wakeups done per grace period by the RCU
grace-period kthread by the square root of the number of CPUs, but of
course by shifting those wakeups to the leaders. In addition, because
the leaders do grace periods on behalf of their respective followers,
the number of wakeups of the followers decreases by up to a factor of two.
Instead of being awakened once when new callbacks arrive and again
at the end of the grace period, the followers are awakened only at
the end of the grace period.
For a numerical example, in a 4096-CPU system, the grace-period kthread
would awaken 64 leaders, each of which would awaken its 63 followers
at the end of the grace period. This compares favorably with the 79
wakeups for the grace-period kthread on an 80-CPU system.
Reported-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-06-24 20:26:11 +04:00
rcutree.rcu_nocb_leader_stride= [KNL]
Set the number of NOCB kthread groups, which
defaults to the square root of the number of
CPUs. Larger numbers reduces the wakeup overhead
on the per-CPU grace-period kthreads, but increases
that same overhead on each group's leader.
2013-10-09 07:23:47 +04:00
rcutree.qhimark= [KNL]
2013-10-27 20:44:03 +04:00
Set threshold of queued RCU callbacks beyond which
batch limiting is disabled.
2006-03-08 08:55:33 +03:00
2013-10-09 07:23:47 +04:00
rcutree.qlowmark= [KNL]
2008-02-03 16:20:26 +03:00
Set threshold of queued RCU callbacks below which
batch limiting is re-enabled.
2006-03-08 08:55:33 +03:00
2013-10-09 07:23:47 +04:00
rcutree.rcu_idle_gp_delay= [KNL]
2012-12-28 23:30:36 +04:00
Set wakeup interval for idle CPUs that have
RCU callbacks (RCU_FAST_NO_HZ=y).
rcu: Control grace-period duration from sysfs
Although almost everyone is well-served by the defaults, some uses of RCU
benefit from shorter grace periods, while others benefit more from the
greater efficiency provided by longer grace periods. Situations requiring
a large number of grace periods to elapse (and wireshark startup has
been called out as an example of this) are helped by lower-latency
grace periods. Furthermore, in some embedded applications, people are
willing to accept a small degradation in update efficiency (due to there
being more of the shorter grace-period operations) in order to gain the
lower latency.
In contrast, those few systems with thousands of CPUs need longer grace
periods because the CPU overhead of a grace period rises roughly
linearly with the number of CPUs. Such systems normally do not make
much use of facilities that require large numbers of grace periods to
elapse, so this is a good tradeoff.
Therefore, this commit allows the durations to be controlled from sysfs.
There are two sysfs parameters, one named "jiffies_till_first_fqs" that
specifies the delay in jiffies from the end of grace-period initialization
until the first attempt to force quiescent states, and the other named
"jiffies_till_next_fqs" that specifies the delay (again in jiffies)
between subsequent attempts to force quiescent states. They both default
to three jiffies, which is compatible with the old hard-coded behavior.
At some future time, it may be possible to automatically increase the
grace-period length with the number of CPUs, but we do not yet have
sufficient data to do a good job. Preliminary data indicates that we
should add an addiitonal jiffy to each of the delays for every 200 CPUs
in the system, but more experimentation is needed. For now, the number
of systems with more than 1,000 CPUs is small enough that this can be
relegated to boot-time hand tuning.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-06-27 07:45:57 +04:00
2013-10-09 07:23:47 +04:00
rcutree.rcu_idle_lazy_gp_delay= [KNL]
2012-12-28 23:30:36 +04:00
Set wakeup interval for idle CPUs that have
only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
Lazy RCU callbacks are those which RCU can
prove do nothing more than free memory.
rcu: Control grace-period duration from sysfs
Although almost everyone is well-served by the defaults, some uses of RCU
benefit from shorter grace periods, while others benefit more from the
greater efficiency provided by longer grace periods. Situations requiring
a large number of grace periods to elapse (and wireshark startup has
been called out as an example of this) are helped by lower-latency
grace periods. Furthermore, in some embedded applications, people are
willing to accept a small degradation in update efficiency (due to there
being more of the shorter grace-period operations) in order to gain the
lower latency.
In contrast, those few systems with thousands of CPUs need longer grace
periods because the CPU overhead of a grace period rises roughly
linearly with the number of CPUs. Such systems normally do not make
much use of facilities that require large numbers of grace periods to
elapse, so this is a good tradeoff.
Therefore, this commit allows the durations to be controlled from sysfs.
There are two sysfs parameters, one named "jiffies_till_first_fqs" that
specifies the delay in jiffies from the end of grace-period initialization
until the first attempt to force quiescent states, and the other named
"jiffies_till_next_fqs" that specifies the delay (again in jiffies)
between subsequent attempts to force quiescent states. They both default
to three jiffies, which is compatible with the old hard-coded behavior.
At some future time, it may be possible to automatically increase the
grace-period length with the number of CPUs, but we do not yet have
sufficient data to do a good job. Preliminary data indicates that we
should add an addiitonal jiffy to each of the delays for every 200 CPUs
in the system, but more experimentation is needed. For now, the number
of systems with more than 1,000 CPUs is small enough that this can be
relegated to boot-time hand tuning.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-06-27 07:45:57 +04:00
2014-08-19 08:12:17 +04:00
rcutorture.cbflood_inter_holdoff= [KNL]
Set holdoff time (jiffies) between successive
callback-flood tests.
rcutorture.cbflood_intra_holdoff= [KNL]
Set holdoff time (jiffies) between successive
bursts of callbacks within a given callback-flood
test.
rcutorture.cbflood_n_burst= [KNL]
Set the number of bursts making up a given
callback-flood test. Set this to zero to
disable callback-flood testing.
rcutorture.cbflood_n_per_burst= [KNL]
Set the number of callbacks to be registered
in a given burst of a callback-flood test.
2013-10-09 07:23:47 +04:00
rcutorture.fqs_duration= [KNL]
2012-04-23 21:54:45 +04:00
Set duration of force_quiescent_state bursts.
2013-10-09 07:23:47 +04:00
rcutorture.fqs_holdoff= [KNL]
2012-04-23 21:54:45 +04:00
Set holdoff time within force_quiescent_state bursts.
2013-10-09 07:23:47 +04:00
rcutorture.fqs_stutter= [KNL]
2012-04-23 21:54:45 +04:00
Set wait time between force_quiescent_state bursts.
2013-10-09 07:23:47 +04:00
rcutorture.gp_exp= [KNL]
Use expedited update-side primitives.
rcutorture.gp_normal= [KNL]
Use normal (non-expedited) update-side primitives.
If both gp_exp and gp_normal are set, do both.
If neither gp_exp nor gp_normal are set, still
do both.
2012-04-23 21:54:45 +04:00
2013-10-09 07:23:47 +04:00
rcutorture.n_barrier_cbs= [KNL]
2012-04-23 21:54:45 +04:00
Set callbacks/threads for rcu_barrier() testing.
2013-10-09 07:23:47 +04:00
rcutorture.nfakewriters= [KNL]
2012-04-23 21:54:45 +04:00
Set number of concurrent RCU writers. These just
stress RCU, they don't participate in the actual
test, hence the "fake".
2013-10-09 07:23:47 +04:00
rcutorture.nreaders= [KNL]
2012-04-23 21:54:45 +04:00
Set number of RCU readers.
2013-10-09 07:23:47 +04:00
rcutorture.object_debug= [KNL]
Enable debug-object double-call_rcu() testing.
rcutorture.onoff_holdoff= [KNL]
2012-04-23 21:54:45 +04:00
Set time (s) after boot for CPU-hotplug testing.
2013-10-09 07:23:47 +04:00
rcutorture.onoff_interval= [KNL]
2012-04-23 21:54:45 +04:00
Set time (s) between CPU-hotplug operations, or
zero to disable CPU-hotplug testing.
2014-09-12 21:36:15 +04:00
rcutorture.torture_runnable= [BOOT]
2013-10-09 07:23:47 +04:00
Start rcutorture running at boot time.
rcutorture.shuffle_interval= [KNL]
2012-04-23 21:54:45 +04:00
Set task-shuffle interval (s). Shuffling tasks
allows some CPUs to go into dyntick-idle mode
during the rcutorture test.
2013-10-09 07:23:47 +04:00
rcutorture.shutdown_secs= [KNL]
2012-04-23 21:54:45 +04:00
Set time (s) after boot system shutdown. This
is useful for hands-off automated testing.
2013-10-09 07:23:47 +04:00
rcutorture.stall_cpu= [KNL]
2012-04-23 21:54:45 +04:00
Duration of CPU stall (s) to test RCU CPU stall
warnings, zero to disable.
2013-10-09 07:23:47 +04:00
rcutorture.stall_cpu_holdoff= [KNL]
2012-04-23 21:54:45 +04:00
Time to wait (s) after boot before inducing stall.
2013-10-09 07:23:47 +04:00
rcutorture.stat_interval= [KNL]
2012-04-23 21:54:45 +04:00
Time (s) between statistics printk()s.
2013-10-09 07:23:47 +04:00
rcutorture.stutter= [KNL]
2012-04-23 21:54:45 +04:00
Time (s) to stutter testing, for example, specifying
five seconds causes the test to run for five seconds,
wait for five seconds, and so on. This tests RCU's
ability to transition abruptly to and from idle.
2013-10-09 07:23:47 +04:00
rcutorture.test_boost= [KNL]
2012-04-23 21:54:45 +04:00
Test RCU priority boosting? 0=no, 1=maybe, 2=yes.
"Maybe" means test if the RCU implementation
under test support RCU priority boosting.
2013-10-09 07:23:47 +04:00
rcutorture.test_boost_duration= [KNL]
2012-04-23 21:54:45 +04:00
Duration (s) of each individual boost test.
2013-10-09 07:23:47 +04:00
rcutorture.test_boost_interval= [KNL]
2012-04-23 21:54:45 +04:00
Interval (s) between each boost test.
2013-10-09 07:23:47 +04:00
rcutorture.test_no_idle_hz= [KNL]
2012-04-23 21:54:45 +04:00
Test RCU's dyntick-idle handling. See also the
rcutorture.shuffle_interval parameter.
2013-10-09 07:23:47 +04:00
rcutorture.torture_type= [KNL]
2012-04-23 21:54:45 +04:00
Specify the RCU implementation to test.
2013-10-09 07:23:47 +04:00
rcutorture.verbose= [KNL]
2012-04-23 21:54:45 +04:00
Enable additional printk() statements.
2013-10-09 07:23:47 +04:00
rcupdate.rcu_expedited= [KNL]
Use expedited grace-period primitives, for
example, synchronize_rcu_expedited() instead
of synchronize_rcu(). This reduces latency,
but can increase CPU utilization, degrade
real-time latency, and degrade energy efficiency.
rcupdate.rcu_cpu_stall_suppress= [KNL]
Suppress RCU CPU stall warning messages.
rcupdate.rcu_cpu_stall_timeout= [KNL]
Set timeout for RCU CPU stall warning messages.
2014-07-02 05:16:30 +04:00
rcupdate.rcu_task_stall_timeout= [KNL]
Set timeout in jiffies for RCU task stall warning
messages. Disable with a value less than or equal
to zero.
2005-09-07 02:17:19 +04:00
rdinit= [KNL]
Format: <full_path>
Run specified binary instead of /init from the ramdisk,
used for early userspace startup. See initrd.
2013-07-09 03:01:42 +04:00
reboot= [KNL]
Format (x86 or x86_64):
[w[arm] | c[old] | h[ard] | s[oft] | g[pio]] \
[[,]s[mp]#### \
[[,]b[ios] | a[cpi] | k[bd] | t[riple] | e[fi] | p[ci]] \
[[,]f[orce]
Where reboot_mode is one of warm (soft) or cold (hard) or gpio,
reboot_type is one of bios, acpi, kbd, triple, efi, or pci,
reboot_force is either force or not specified,
reboot_cpu is s[mp]#### with #### being the processor
to be used for rebooting.
2005-04-17 02:20:36 +04:00
2008-07-04 21:00:09 +04:00
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
2009-02-04 12:12:08 +03:00
See Documentation/cgroups/cpusets.txt.
2008-07-04 21:00:09 +04:00
PM / sleep: Introduce command line argument for sleep state enumeration
On some systems the platform doesn't support neither
PM_SUSPEND_MEM nor PM_SUSPEND_STANDBY, so PM_SUSPEND_FREEZE is the
only available system sleep state. However, some user space frameworks
only use the "mem" and (sometimes) "standby" sleep state labels, so
the users of those systems need to modify user space in order to be
able to use system suspend at all and that is not always possible.
For this reason, add a new kernel command line argument,
relative_sleep_states, allowing the users of those systems to change
the way in which the kernel assigns labels to system sleep states.
Namely, for relative_sleep_states=1, the "mem", "standby" and "freeze"
labels will enumerate the available system sleem states from the
deepest to the shallowest, respectively, so that "mem" is always
present in /sys/power/state and the other state strings may or may
not be presend depending on what is supported by the platform.
Update system sleep states documentation to reflect this change.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-26 15:40:59 +04:00
relative_sleep_states=
[SUSPEND] Use sleep state labeling where the deepest
state available other than hibernation is always "mem".
Format: { "0" | "1" }
0 -- Traditional sleep state labels.
1 -- Relative sleep state labels.
2005-04-17 02:20:36 +04:00
reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
2007-07-31 11:37:59 +04:00
reservetop= [X86-32]
2006-09-26 10:32:25 +04:00
Format: nn[KMG]
Reserves a hole at the top of the kernel virtual
address space.
2010-08-26 03:38:20 +04:00
reservelow= [X86]
Format: nn[K]
Set the amount of memory to reserve for BIOS at
the bottom of the address space.
2006-09-27 12:50:44 +04:00
reset_devices [KNL] Force drivers to reset the underlying device
during initialization.
2005-10-23 23:57:11 +04:00
resume= [SWSUSP]
Specify the partition device for software suspend
2012-05-14 23:45:31 +04:00
Format:
{/dev/<dev> | PARTUUID=<uuid> | <int>:<int> | <hex>}
2005-04-17 02:20:36 +04:00
2006-12-07 07:34:13 +03:00
resume_offset= [SWSUSP]
Specify the offset from the beginning of the partition
given by "resume=" at which the swap header is located,
in <PAGE_SIZE> units (needed only for swap files).
See Documentation/power/swsusp-and-swap-files.txt
2011-10-11 01:38:41 +04:00
resumedelay= [HIBERNATION] Delay (in seconds) to pause before attempting to
read the resume files
2011-10-06 22:34:46 +04:00
resumewait [HIBERNATION] Wait (indefinitely) for resume device to show up.
Useful for devices that are detected asynchronously
(e.g. USB and MMC devices).
2010-09-10 01:06:23 +04:00
hibernate= [HIBERNATION]
noresume Don't check if there's a hibernation image
present during boot.
nocompress Don't compress/decompress hibernation images.
2014-06-14 00:30:35 +04:00
no Disable hibernation and resume.
2010-09-10 01:06:23 +04:00
2007-02-10 12:44:33 +03:00
retain_initrd [RAM] Keep initrd memory after extraction
2005-04-17 02:20:36 +04:00
rhash_entries= [KNL,NET]
Set number of hash buckets for route cache
ro [KNL] Mount root device read-only on boot
root= [KNL] Root filesystem
2011-08-04 03:21:08 +04:00
See name_to_dev_t comment in init/do_mounts.c.
2005-04-17 02:20:36 +04:00
rootdelay= [KNL] Delay (in seconds) to pause before attempting to
mount the root filesystem
rootflags= [KNL] Set root filesystem mount option string
rootfstype= [KNL] Set root filesystem type
2007-07-16 10:40:35 +04:00
rootwait [KNL] Wait (indefinitely) for root device to show up.
Useful for devices that are detected asynchronously
(e.g. USB and MMC devices).
2013-03-29 05:41:46 +04:00
rproc_mem=nn[KMG][@address]
[KNL,ARM,CMA] Remoteproc physical memory block.
Memory area to be used by remote processor image,
managed by CMA.
2005-04-17 02:20:36 +04:00
rw [KNL] Mount root device read-write on boot
S [KNL] Run init in single mode
2014-07-18 19:37:08 +04:00
s390_iommu= [HW,S390]
Set s390 IOTLB flushing mode
strict
With strict flushing every unmap operation will result in
an IOTLB flush. Default is lazy flushing before reuse,
which is faster.
2005-04-17 02:20:36 +04:00
sa1100ir [NET]
See drivers/net/irda/sa1100_ir.c.
sbni= [NET] Granch SBNI12 leased line adapter
2005-10-23 23:57:11 +04:00
2009-11-18 03:22:15 +03:00
sched_debug [KNL] Enables verbose scheduler debug messages.
2012-05-08 14:20:58 +04:00
skew_tick= [KNL] Offset the periodic timer tick per cpu to mitigate
xtime_lock contention on larger systems, and/or RCU lock
contention on all systems with CONFIG_MAXSMP set.
Format: { "0" | "1" }
0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
1 -- enable.
Note: increases power consumption, thus should only be
enabled if running jitter sensitive (HPC/RT) workloads.
2009-04-06 02:55:22 +04:00
security= [SECURITY] Choose a security module to enable at boot.
If this boot parameter is not specified, only the first
security module asking for security registration will be
loaded. An invalid security module name will be treated
as if no module has been chosen.
selinux= [SELINUX] Disable or enable SELinux at boot time.
2005-04-17 02:20:36 +04:00
Format: { "0" | "1" }
See security/selinux/Kconfig help text.
0 -- disable.
1 -- enable.
Default value is set via kernel config option.
If enabled at boot time, /selinux/disable can be used
later to disable prior to initial policy load.
2010-07-30 01:48:09 +04:00
apparmor= [APPARMOR] Disable or enable AppArmor at boot time
Format: { "0" | "1" }
See security/apparmor/Kconfig help text
0 -- disable.
1 -- enable.
Default value is set via kernel config option.
2007-07-31 11:37:59 +04:00
serialnumber [BUGS=X86-32]
2005-04-17 02:20:36 +04:00
shapers= [NET]
Maximal number of shapers.
2005-10-23 23:57:11 +04:00
2008-08-22 12:32:50 +04:00
show_msr= [x86] show boot-time MSR settings
Format: { <integer> }
Show boot-time (BIOS-initialized) MSR settings.
The parameter means the number of CPUs to show,
for example 1 means boot CPU only.
2005-04-17 02:20:36 +04:00
simeth= [IA-64]
simscsi=
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
slram= [HW,MTD]
2011-10-19 09:09:28 +04:00
slab_max_order= [MM, SLAB]
Determines the maximum allowed order for slabs.
A high setting may cause OOMs due to memory
fragmentation. Defaults to 1 for systems with
more than 32MB of RAM, 0 otherwise.
2007-07-16 10:38:14 +04:00
slub_debug[=options[,slabs]] [MM, SLUB]
Enabling slub_debug allows one to determine the
culprit if slab objects become corrupted. Enabling
slub_debug can create guard zones around objects and
may poison objects when not in use. Also tracks the
last alloc / free. For more information see
Documentation/vm/slub.txt.
2007-05-31 11:40:47 +04:00
slub_max_order= [MM, SLUB]
2007-07-16 10:38:14 +04:00
Determines the maximum allowed order for slabs.
A high setting may cause OOMs due to memory
fragmentation. For more information see
Documentation/vm/slub.txt.
2007-05-31 11:40:47 +04:00
slub_min_objects= [MM, SLUB]
2007-07-16 10:38:14 +04:00
The minimum number of objects per slab. SLUB will
increase the slab order up to slub_max_order to
generate a sufficiently large slab able to contain
the number of objects indicated. The higher the number
of objects the smaller the overhead of tracking slabs
and the less frequently locks need to be acquired.
2007-05-31 11:40:47 +04:00
For more information see Documentation/vm/slub.txt.
slub_min_order= [MM, SLUB]
2012-02-14 19:26:42 +04:00
Determines the minimum page order for slabs. Must be
2007-07-16 10:38:14 +04:00
lower than slub_max_order.
2007-05-31 11:40:47 +04:00
For more information see Documentation/vm/slub.txt.
slub_nomerge [MM, SLUB]
2007-07-16 10:38:14 +04:00
Disable merging of slabs with similar size. May be
2007-05-31 11:40:47 +04:00
necessary if there is some reason to distinguish
2007-07-16 10:38:14 +04:00
allocs to different slabs. Debug options disable
merging on their own.
2007-05-31 11:40:47 +04:00
For more information see Documentation/vm/slub.txt.
2005-04-17 02:20:36 +04:00
smart2= [HW]
Format: <io1>[,<io2>[,...,<io8>]]
2007-05-08 11:36:05 +04:00
smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
smsc-ircc2.ircc_sir= [HW] SIR base I/O port
smsc-ircc2.ircc_fir= [HW] FIR base I/O port
smsc-ircc2.ircc_irq= [HW] IRQ line
smsc-ircc2.ircc_dma= [HW] DMA channel
smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
0: Toshiba Satellite 1800 (GP data pin select)
1: Fast pin select (default)
2: ATC IRMode
2008-05-12 23:21:04 +04:00
softlockup_panic=
[KNL] Should the soft-lockup detector generate panics.
2011-04-05 02:02:24 +04:00
Format: <integer>
2008-05-12 23:21:04 +04:00
2014-06-24 00:22:05 +04:00
softlockup_all_cpu_backtrace=
[KNL] Should the soft-lockup detector generate
backtraces on all cpus.
Format: <integer>
2005-04-17 02:20:36 +04:00
sonypi.*= [HW] Sony Programmable I/O Control Device driver
2011-08-15 04:02:26 +04:00
See Documentation/laptops/sonypi.txt
2005-04-17 02:20:36 +04:00
spia_io_base= [HW,MTD]
spia_fio_base=
spia_pedr=
spia_peddr=
2008-12-17 07:06:40 +03:00
stacktrace [FTRACE]
Enabled the stack tracer on boot up.
2011-12-20 07:01:00 +04:00
stacktrace_filter=[function-list]
[FTRACE] Limit the functions that the stack tracer
will trace at boot up. function-list is a comma separated
list of functions. This list can be changed at run
time by the stack_trace_filter file in the debugfs
tracing directory. Note, this enables stack tracing
and the stacktrace above is not needed.
2005-04-17 02:20:36 +04:00
sti= [PARISC,HW]
Format: <num>
Set the STI (builtin display/keyboard on the HP-PARISC
machines) console (graphic card) which should be used
as the initial boot-console.
See also comment in drivers/video/console/sticore.c.
sti_font= [HW]
See comment in drivers/video/console/sticore.c.
stifb= [HW]
Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
2009-08-09 23:06:19 +04:00
sunrpc.min_resvport=
sunrpc.max_resvport=
[NFS,SUNRPC]
SunRPC servers often require that client requests
originate from a privileged port (i.e. a port in the
range 0 < portnr < 1024).
An administrator who wishes to reserve some of these
ports for other uses may adjust the range that the
kernel's sunrpc client considers to be privileged
using these two parameters to set the minimum and
maximum port values.
2007-03-06 12:42:23 +03:00
sunrpc.pool_mode=
[NFS]
Control how the NFS server code allocates CPUs to
service thread pools. Depending on how many NICs
you have and where their interrupts are bound, this
option will affect which CPUs will do NFS serving.
Note: this parameter cannot be changed while the
NFS server is running.
auto the server chooses an appropriate mode
automatically using heuristics
global a single global pool contains all CPUs
percpu one pool for each CPU
pernode one pool for each NUMA node (equivalent
to global on non-NUMA machines)
2009-08-09 23:06:19 +04:00
sunrpc.tcp_slot_table_entries=
sunrpc.udp_slot_table_entries=
[NFS,SUNRPC]
Sets the upper limit on the number of simultaneous
RPC calls that can be sent from the client to a
server. Increasing these values may allow you to
improve throughput, but will also increase the
amount of memory reserved for use by the client.
2013-08-23 03:35:46 +04:00
swapaccount=[0|1]
2010-11-24 23:57:08 +03:00
[KNL] Enable accounting of swap in memory resource
controller if no parameter or 1 is given or disable
it if 0 is given (See Documentation/cgroups/memory.txt)
2013-11-27 16:48:09 +04:00
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
Format: { <int> | force }
<int> -- Number of I/O TLB slabs
force -- force using of bounce buffers even if they
wouldn't be automatically used by the kernel
2005-10-23 23:57:11 +04:00
2005-04-17 02:20:36 +04:00
switches= [HW,M68k]
2010-09-08 18:54:17 +04:00
sysfs.deprecated=0|1 [KNL]
Enable/disable old style sysfs layout for old udev
on older distributions. When this option is enabled
very new udev will not work anymore. When this option
is disabled (or CONFIG_SYSFS_DEPRECATED not compiled)
in older udev will not work anymore.
Default depends on CONFIG_SYSFS_DEPRECATED_V2 set in
the kernel configuration.
2006-12-13 11:34:36 +03:00
sysrq_always_enabled
[KNL]
Ignore sysrq setting - this boot parameter will
neutralize any effect of /proc/sys/kernel/sysrq.
Useful for debugging.
2005-04-17 02:20:36 +04:00
tdfx= [HW,DRM]
2008-07-24 08:28:33 +04:00
test_suspend= [SUSPEND]
Specify "mem" (for Suspend-to-RAM) or "standby" (for
standby suspend) as the system sleep state to briefly
enter during system startup. The system is woken from
this state using a wakeup-capable RTC alarm.
2005-04-17 02:20:36 +04:00
thash_entries= [KNL,NET]
Set number of hash buckets for TCP connection
2007-08-12 08:12:54 +04:00
thermal.act= [HW,ACPI]
-1: disable all active trip points in all thermal zones
<degrees C>: override all lowest active trip points
2007-08-14 23:49:32 +04:00
thermal.crt= [HW,ACPI]
-1: disable all critical trip points in all thermal zones
2008-10-17 10:41:20 +04:00
<degrees C>: override all critical trip points
2007-08-14 23:49:32 +04:00
2007-08-12 08:12:44 +04:00
thermal.nocrt= [HW,ACPI]
Set to disable actions on ACPI thermal zone
critical and hot trip points.
2007-08-12 08:12:17 +04:00
thermal.off= [HW,ACPI]
1: disable ACPI thermal control
2007-08-12 08:12:35 +04:00
thermal.psv= [HW,ACPI]
-1: disable all passive trip points
2008-12-19 21:57:32 +03:00
<degrees C>: override all passive trip points to this
value
2007-08-12 08:12:35 +04:00
ACPI: thermal: expose "thermal.tzp=" to set global polling frequency
Thermal Zone Polling frequency (_TZP) is an optional ACPI object
recommending the rate that the OS should poll the associated thermal zone.
If _TZP is 0, no polling should be used.
If _TZP is non-zero, then the platform recommends that
the OS poll the thermal zone at the specified rate.
The minimum period is 30 seconds.
The maximum period is 5 minutes.
(note _TZP and thermal.tzp units are in deci-seconds,
so _TZP = 300 corresponds to 30 seconds)
If _TZP is not present, ACPI 3.0b recommends that the
thermal zone be polled at an "OS provided default frequency".
However, common industry practice is:
1. The BIOS never specifies any _TZP
2. High volume OS's from this century never poll any thermal zones
Ie. The OS depends on the platform's ability to
provoke thermal events when necessary, and
the "OS provided default frequency" is "never":-)
There is a proposal that ACPI 4.0 be updated to reflect
common industry practice -- ie. no _TZP, no polling.
The Linux kernel already follows this practice --
thermal zones are not polled unless _TZP is present and non-zero.
But thermal zone polling is useful as a workaround for systems
which have ACPI thermal control, but have an issue preventing
thermal events. Indeed, some Linux distributions still
set a non-zero thermal polling frequency for this reason.
But rather than ask the user to write a polling frequency
into all the /proc/acpi/thermal_zone/*/polling_frequency
files, here we simply document and expose the already
existing module parameter to do the same at system level,
to simplify debugging those broken platforms.
Note that thermal.tzp is a module-load time parameter only.
Signed-off-by: Len Brown <len.brown@intel.com>
2007-08-12 08:12:26 +04:00
thermal.tzp= [HW,ACPI]
Specify global default ACPI thermal zone polling rate
<deci-seconds>: poll all this frequency
0: no polling (default)
2011-02-24 02:52:23 +03:00
threadirqs [KNL]
Force threading of all interrupt handlers except those
2012-02-14 19:26:42 +04:00
marked explicitly IRQF_NO_THREAD.
2011-02-24 02:52:23 +03:00
2013-05-09 01:12:44 +04:00
tmem [KNL,XEN]
Enable the Transcendent memory driver if built-in.
tmem.cleancache=0|1 [KNL, XEN]
Default is on (1). Disable the usage of the cleancache
API to send anonymous pages to the hypervisor.
tmem.frontswap=0|1 [KNL, XEN]
Default is on (1). Disable the usage of the frontswap
2013-05-14 21:56:42 +04:00
API to send swap pages to the hypervisor. If disabled
the selfballooning and selfshrinking are force disabled.
2013-05-09 01:12:44 +04:00
tmem.selfballooning=0|1 [KNL, XEN]
Default is on (1). Disable the driving of swap pages
to the hypervisor.
tmem.selfshrinking=0|1 [KNL, XEN]
Default is on (1). Partial swapoff that immediately
transfers pages from Xen hypervisor back to the
kernel based on different criteria.
2008-12-25 15:39:23 +03:00
topology= [S390]
Format: {off | on}
Specify if the kernel should make use of the cpu
2011-04-05 02:04:46 +04:00
topology information if the hardware supports this.
The scheduler will make use of this information and
2008-12-25 15:39:23 +03:00
e.g. base its process migration decisions on it.
2010-10-25 18:10:43 +04:00
Default is on.
2008-12-25 15:39:23 +03:00
2005-04-17 02:20:36 +04:00
tp720= [HW,PS2]
2010-03-25 06:55:32 +03:00
tpm_suspend_pcr=[HW,TPM]
Format: integer pcr id
Specify that at suspend time, the tpm driver
should extend the specified pcr with zeros,
as a workaround for some chips which fail to
flush the last written pcr on TPM_SaveState.
This will guarantee that all the other pcrs
are saved.
2009-06-24 13:33:15 +04:00
trace_buf_size=nn[KMG]
[FTRACE] will set tracing buffer size.
2009-03-10 07:57:10 +03:00
2009-07-01 06:47:05 +04:00
trace_event=[event-list]
[FTRACE] Set and start specified trace events in order
to facilitate early boot debugging.
See also Documentation/trace/events.txt
2012-11-02 06:56:07 +04:00
trace_options=[option-list]
[FTRACE] Enable or disable tracer options at boot.
The option-list is a comma delimited list of options
that can be enabled or disabled just as if you were
to echo the option name into
/sys/kernel/debug/tracing/trace_options
For example, to enable stacktrace option (to dump the
stack trace of each event), add to the command line:
trace_options=stacktrace
See also Documentation/trace/ftrace.txt "trace options"
section.
2013-06-15 00:21:43 +04:00
traceoff_on_warning
[FTRACE] enable this option to disable tracing when a
warning is hit. This turns off "tracing_on". Tracing can
be enabled again by echoing '1' into the "tracing_on"
file located in /sys/kernel/debug/tracing/
This option is useful, as it disables the trace before
the WARNING dump is called, which prevents the trace to
be filled with content caused by the warning output.
This option can also be set at run time via the sysctl
option: kernel/traceoff_on_warning
2012-03-22 03:34:02 +04:00
transparent_hugepage=
[KNL]
Format: [always|madvise|never]
Can be used to control the default behavior of the system
with respect to transparent hugepages.
See Documentation/vm/transhuge.txt for more details.
2009-08-18 03:40:47 +04:00
tsc= Disable clocksource stability checks for TSC.
2008-10-25 04:22:01 +04:00
Format: <string>
[x86] reliable: mark tsc clocksource as reliable, this
2009-08-18 03:40:47 +04:00
disables clocksource verification at runtime, as well
as the stability checks done at bootup. Used to enable
high-resolution timer mode on older hardware, and in
virtualized environment.
2010-10-05 04:03:20 +04:00
[x86] noirqtime: Do not use TSC to do irq accounting.
Used to run time disable IRQ_TIME_ACCOUNTING on any
platforms where RDTSC is slow and this accounting
can add overhead.
2008-10-25 04:22:01 +04:00
2005-10-23 23:57:11 +04:00
turbografx.map[2|3]= [HW,JOY]
TurboGraFX parallel port interface
Format:
<port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
2005-04-17 02:20:36 +04:00
See also Documentation/input/joystick-parport.txt
2011-05-31 19:22:05 +04:00
udbg-immortal [PPC] When debugging early kernel crashes that
happen after console_init() and before a proper
console driver takes over, this boot options might
help "seeing" what's going on.
2009-10-07 04:37:59 +04:00
uhash_entries= [KNL,NET]
Set number of hash buckets for UDP/UDP-Lite connections
2006-12-06 00:29:55 +03:00
uhci-hcd.ignore_oc=
[USB] Ignore overcurrent events (default N).
Some badly-designed motherboards generate lots of
bogus events, for ports that aren't wired to
anything. Set this parameter to avoid log spamming.
Note that genuine overcurrent events won't be
reported either.
2008-07-20 02:32:54 +04:00
unknown_nmi_panic
2011-04-05 02:02:24 +04:00
[X86] Cause panic on unknown NMI.
2008-07-20 02:32:54 +04:00
2011-05-31 23:31:08 +04:00
usbcore.authorized_default=
[USB] Default USB device authorization:
(default -1 = authorized except for wireless USB,
0 = not authorized, 1 = authorized)
2007-02-20 23:00:53 +03:00
usbcore.autosuspend=
[USB] The autosuspend time delay (in seconds) used
for newly-detected USB devices (default 2). This
is the time required before an idle device will be
autosuspended. Devices for which the delay is set
2007-03-13 23:39:15 +03:00
to a negative value won't be autosuspended at all.
2007-02-20 23:00:53 +03:00
2008-10-10 18:24:45 +04:00
usbcore.usbfs_snoop=
[USB] Set to log all usbfs traffic (default 0 = off).
usbcore.blinkenlights=
[USB] Set to cycle leds on hubs (default 0 = off).
usbcore.old_scheme_first=
[USB] Start with the old device initialization
scheme (default 0 = off).
2011-11-18 01:41:35 +04:00
usbcore.usbfs_memory_mb=
[USB] Memory limit (in MB) for buffers allocated by
usbfs (default = 16, 0 = max = 2047).
2008-10-10 18:24:45 +04:00
usbcore.use_both_schemes=
[USB] Try the other device initialization scheme
if the first one fails (default 1 = enabled).
usbcore.initial_descriptor_timeout=
[USB] Specifies timeout for the initial 64-byte
USB_REQ_GET_DESCRIPTOR request in milliseconds
(default 5000 = 5.0 seconds).
2005-04-17 02:20:36 +04:00
usbhid.mousepoll=
[USBHID] The interval which mice are to be polled at.
2005-10-23 23:57:11 +04:00
2008-11-10 22:07:45 +03:00
usb-storage.delay_use=
[UMS] The delay in seconds before a new device is
scanned for Logical Units (default 5).
usb-storage.quirks=
[UMS] A list of quirks entries to supplement or
override the built-in unusual_devs list. List
entries are separated by commas. Each entry has
the form VID:PID:Flags where VID and PID are Vendor
and Product ID values (4-digit hex numbers) and
Flags is a set of characters, each corresponding
to a common usb-storage quirk flag as follows:
2008-12-15 18:40:06 +03:00
a = SANE_SENSE (collect more than 18 bytes
of sense data);
2009-12-08 00:39:16 +03:00
b = BAD_SENSE (don't collect more than 18
bytes of sense data);
2008-11-10 22:07:45 +03:00
c = FIX_CAPACITY (decrease the reported
device capacity by one sector);
2011-05-19 00:42:34 +04:00
d = NO_READ_DISC_INFO (don't use
READ_DISC_INFO command);
e = NO_READ_CAPACITY_16 (don't use
READ_CAPACITY_16 command);
2008-12-15 18:40:06 +03:00
h = CAPACITY_HEURISTICS (decrease the
reported device capacity by one
sector if the number is odd);
2008-11-10 22:07:45 +03:00
i = IGNORE_DEVICE (don't bind to this
device);
l = NOT_LOCKABLE (don't try to lock and
unlock ejectable media);
m = MAX_SECTORS_64 (don't transfer more
than 64 sectors = 32 KB at a time);
2011-06-07 19:35:52 +04:00
n = INITIAL_READ10 (force a retry of the
initial READ(10) command);
2008-12-15 18:40:06 +03:00
o = CAPACITY_OK (accept the capacity
reported by the device);
2012-07-08 07:05:28 +04:00
p = WRITE_CACHE (the device cache is ON
by default);
2008-11-10 22:07:45 +03:00
r = IGNORE_RESIDUE (the device reports
bogus residue values);
s = SINGLE_LUN (the device has only one
Logical Unit);
w = NO_WP_DETECT (don't test whether the
medium is write-protected).
Example: quirks=0419:aaf5:rl,0421:0433:rc
2011-08-13 23:34:50 +04:00
user_debug= [KNL,ARM]
Format: <int>
See arch/arm/Kconfig.debug help text.
1 - undefined instruction events
2 - system calls
4 - invalid data aborts
8 - SIGSEGV faults
16 - SIGBUS faults
Example: user_debug=31
2010-02-17 13:38:10 +03:00
userpte=
[X86] Flags controlling user PTE allocations.
nohigh = do not allocate PTE pages in
HIGHMEM regardless of setting
of CONFIG_HIGHPTE.
2009-04-14 12:33:43 +04:00
vdso= [X86,SH]
2014-03-14 03:01:26 +04:00
On X86_32, this is an alias for vdso32=. Otherwise:
vdso=1: enable VDSO (the default)
[PATCH] vdso: randomize the i386 vDSO by moving it into a vma
Move the i386 VDSO down into a vma and thus randomize it.
Besides the security implications, this feature also helps debuggers, which
can COW a vma-backed VDSO just like a normal DSO and can thus do
single-stepping and other debugging features.
It's good for hypervisors (Xen, VMWare) too, which typically live in the same
high-mapped address space as the VDSO, hence whenever the VDSO is used, they
get lots of guest pagefaults and have to fix such guest accesses up - which
slows things down instead of speeding things up (the primary purpose of the
VDSO).
There's a new CONFIG_COMPAT_VDSO (default=y) option, which provides support
for older glibcs that still rely on a prelinked high-mapped VDSO. Newer
distributions (using glibc 2.3.3 or later) can turn this option off. Turning
it off is also recommended for security reasons: attackers cannot use the
predictable high-mapped VDSO page as syscall trampoline anymore.
There is a new vdso=[0|1] boot option as well, and a runtime
/proc/sys/vm/vdso_enabled sysctl switch, that allows the VDSO to be turned
on/off.
(This version of the VDSO-randomization patch also has working ELF
coredumping, the previous patch crashed in the coredumping code.)
This code is a combined work of the exec-shield VDSO randomization
code and Gerd Hoffmann's hypervisor-centric VDSO patch. Rusty Russell
started this patch and i completed it.
[akpm@osdl.org: cleanups]
[akpm@osdl.org: compile fix]
[akpm@osdl.org: compile fix 2]
[akpm@osdl.org: compile fix 3]
[akpm@osdl.org: revernt MAXMEM change]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Cc: Gerd Hoffmann <kraxel@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 13:53:50 +04:00
vdso=0: disable VDSO mapping
2014-03-14 03:01:26 +04:00
vdso32= [X86] Control the 32-bit vDSO
vdso32=1: enable 32-bit VDSO
vdso32=0 or vdso32=2: disable 32-bit VDSO
See the help text for CONFIG_COMPAT_VDSO for more
details. If CONFIG_COMPAT_VDSO is set, the default is
vdso32=0; otherwise, the default is vdso32=1.
For compatibility with older kernels, vdso32=2 is an
alias for vdso32=0.
Try vdso32=0 if you encounter an error that says:
dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2008-01-30 15:30:43 +03:00
2007-07-17 16:22:55 +04:00
vector= [IA-64,SMP]
vector=percpu: enable percpu vector domain
2005-04-17 02:20:36 +04:00
video= [FB] Frame buffer configuration
See Documentation/fb/modedb.txt.
2013-06-20 11:08:55 +04:00
video.brightness_switch_enabled= [0,1]
If set to 1, on receiving an ACPI notify event
generated by hotkey, video driver will adjust brightness
level and then send out the event to user space through
the allocated input device; If set to 0, video driver
will only send out the event without touching backlight
brightness level.
2014-07-14 21:35:45 +04:00
default: 1
2013-06-20 11:08:55 +04:00
2012-05-09 21:30:16 +04:00
virtio_mmio.device=
[VMMIO] Memory mapped virtio (platform) device.
<size>@<baseaddr>:<irq>[:<id>]
where:
<size> := size (can use standard suffixes
like K, M and G)
<baseaddr> := physical base address
<irq> := interrupt number (as passed to
request_irq())
<id> := (optional) platform device id
example:
virtio_mmio.device=1K@0x100b0000:48:7
Can be used multiple times for multiple devices.
2007-07-31 11:37:59 +04:00
vga= [BOOT,X86-32] Select a particular video mode
2009-02-20 00:48:14 +03:00
See Documentation/x86/boot.txt and
2005-10-23 23:57:11 +04:00
Documentation/svga.txt.
2005-04-17 02:20:36 +04:00
Use vga=ask for menu.
This is actually a boot loader parameter; the value is
passed to the kernel using a special protocol.
2005-10-23 23:57:11 +04:00
vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
2005-04-17 02:20:36 +04:00
size of <nn>. This can be used to increase the
minimum size (128MB on x86). It can also be used to
decrease the size and leave more room for directly
mapped kernel RAM.
2006-06-29 17:08:25 +04:00
vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
Format: <command>
2005-04-17 02:20:36 +04:00
2006-06-29 17:08:25 +04:00
vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
Format: <command>
vmpoff= [KNL,S390] Perform z/VM CP command after power off.
Format: <command>
2005-10-23 23:57:11 +04:00
2011-08-10 19:15:32 +04:00
vsyscall= [X86-64]
Controls the behavior of vsyscalls (i.e. calls to
fixed addresses of 0xffffffffff600x00 from legacy
code). Most statically-linked binaries and older
versions of glibc use these calls. Because these
functions are at fixed addresses, they make nice
targets for exploits that can control RIP.
2011-11-08 04:33:41 +04:00
emulate [default] Vsyscalls turn into traps and are
emulated reasonably safely.
2011-08-10 19:15:32 +04:00
2011-11-08 04:33:41 +04:00
native Vsyscalls are native syscall instructions.
2011-08-10 19:15:32 +04:00
This is a little bit faster than trapping
and makes a few dynamic recompilers work
better than they would in emulation mode.
It also makes exploits much easier to write.
none Vsyscalls don't work at all. This makes
them quite hard to use for exploits but
might break your system.
2013-08-04 15:09:50 +04:00
vt.color= [VT] Default text color.
Format: 0xYX, X = foreground, Y = background.
Default: 0x07 = light gray on black.
2009-12-16 03:45:39 +03:00
vt.cur_default= [VT] Default cursor shape.
Format: 0xCCBBAA, where AA, BB, and CC are the same as
the parameters of the <Esc>[?A;B;Cc escape sequence;
see VGA-softcursor.txt. Default: 2 = underline.
2009-04-06 02:55:22 +04:00
vt.default_blu= [VT]
Format: <blue0>,<blue1>,<blue2>,...,<blue15>
Change the default blue palette of the console.
This is a 16-member array composed of values
ranging from 0-255.
vt.default_grn= [VT]
Format: <green0>,<green1>,<green2>,...,<green15>
Change the default green palette of the console.
This is a 16-member array composed of values
ranging from 0-255.
vt.default_red= [VT]
Format: <red0>,<red1>,<red2>,...,<red15>
Change the default red palette of the console.
This is a 16-member array composed of values
ranging from 0-255.
vt.default_utf8=
[VT]
Format=<0|1>
Set system-wide default UTF-8 mode for all tty's.
Default is 1, i.e. UTF-8 mode is enabled for all
newly opened terminals.
2009-11-13 23:14:11 +03:00
vt.global_cursor_default=
[VT]
Format=<-1|0|1>
Set system-wide default for whether a cursor
is shown on new VTs. Default is -1,
i.e. cursors will be created by default unless
overridden by individual drivers. 0 will hide
cursors, 1 will display them.
2013-08-04 15:09:50 +04:00
vt.italic= [VT] Default color for italic text; 0-15.
Default: 2 = green.
vt.underline= [VT] Default color for underlined text; 0-15.
Default: 3 = cyan.
2010-05-03 22:42:52 +04:00
watchdog timers [HW,WDT] For information on watchdog timers,
see Documentation/watchdog/watchdog-parameters.txt
or other driver-specific files in the
Documentation/watchdog/ directory.
2005-04-17 02:20:36 +04:00
2013-04-01 22:23:38 +04:00
workqueue.disable_numa
By default, all work items queued to unbound
workqueues are affine to the NUMA nodes they're
issued on, which results in better behavior in
general. If NUMA affinity needs to be disabled for
whatever reason, this option can be used. Note
that this also can be controlled per-workqueue for
workqueues visible under /sys/bus/workqueue/.
2013-04-08 15:15:40 +04:00
workqueue.power_efficient
Per-cpu workqueues are generally preferred because
they show better performance thanks to cache
locality; unfortunately, per-cpu workqueues tend to
be more power hungry than unbound workqueues.
Enabling this makes the per-cpu workqueues which
were observed to contribute significantly to power
consumption unbound, leading to measurably lower
power usage at the cost of small performance
overhead.
The default value of this parameter is determined by
the config option CONFIG_WQ_POWER_EFFICIENT_DEFAULT.
2009-04-06 02:55:22 +04:00
x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
default x2apic cluster mode on platforms
supporting x2apic.
2013-10-18 02:35:29 +04:00
x86_intel_mid_timer= [X86-32,APBT]
Choose timer option for x86 Intel MID platform.
2009-09-02 18:37:17 +04:00
Two valid options are apbt timer only and lapic timer
plus one apbt timer for broadcast timer.
2013-10-18 02:35:29 +04:00
x86_intel_mid_timer=apbt_only | lapic_and_apbt
2009-09-02 18:37:17 +04:00
2010-05-14 15:44:30 +04:00
xen_emul_unplug= [HW,X86,XEN]
Unplug Xen emulated devices
Format: [unplug0,][unplug1]
ide-disks -- unplug primary master IDE devices
aux-ide-disks -- unplug non-primary-master IDE devices
nics -- unplug network devices
all -- unplug all emulated devices (NICs and IDE disks)
2010-08-23 14:59:29 +04:00
unnecessary -- unplugging emulated devices is
unnecessary even if the host did not respond to
the unplug protocol
2010-08-23 14:59:28 +04:00
never -- do not unplug even if version check succeeds
2010-05-14 15:44:30 +04:00
2013-09-25 18:07:20 +04:00
xen_nopvspin [X86,XEN]
Disables the ticketlock slowpath using Xen PV
optimizations.
2014-07-11 19:51:35 +04:00
xen_nopv [X86]
Disables the PV optimizations forcing the HVM guest to
run as generic HVM guest with no PV drivers.
2005-04-17 02:20:36 +04:00
xirc2ps_cs= [NET,PCMCIA]
2005-10-23 23:57:11 +04:00
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
2005-04-17 02:20:36 +04:00
2005-10-23 23:57:11 +04:00
______________________________________________________________________
2005-04-17 02:20:36 +04:00
TODO:
Add more DRM drivers.