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-rw-r--r--Documentation/kernel-parameters.txt124
1 files changed, 102 insertions, 22 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 33121d6c827..8fd5aa40585 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -34,6 +34,7 @@ parameter is applicable:
ALSA ALSA sound support is enabled.
APIC APIC support is enabled.
APM Advanced Power Management support is enabled.
+ AVR32 AVR32 architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
BLACKFIN Blackfin architecture is enabled.
DRM Direct Rendering Management support is enabled.
@@ -167,6 +168,11 @@ and is between 256 and 4096 characters. It is defined in the file
acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
Format: <irq>,<irq>...
+ acpi_new_pts_ordering [HW,ACPI]
+ Enforce the ACPI 2.0 ordering of the _PTS control
+ method wrt putting devices into low power states
+ default: pre ACPI 2.0 ordering of _PTS
+
acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
@@ -369,7 +375,8 @@ and is between 256 and 4096 characters. It is defined in the file
configured. Potentially dangerous and should only be
used if you are entirely sure of the consequences.
- chandev= [HW,NET] Generic channel device initialisation
+ ccw_timeout_log [S390]
+ See Documentation/s390/CommonIO for details.
checkreqprot [SELINUX] Set initial checkreqprot flag value.
Format: { "0" | "1" }
@@ -381,6 +388,12 @@ and is between 256 and 4096 characters. It is defined in the file
Value can be changed at runtime via
/selinux/checkreqprot.
+ cio_ignore= [S390]
+ See Documentation/s390/CommonIO for details.
+
+ cio_msg= [S390]
+ See Documentation/s390/CommonIO for details.
+
clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
[Deprecated]
Forces specified clocksource (if available) to be used
@@ -408,8 +421,21 @@ and is between 256 and 4096 characters. It is defined in the file
[SPARC64] tick
[X86-64] hpet,tsc
- code_bytes [IA32] How many bytes of object code to print in an
- oops report.
+ clearcpuid=BITNUM [X86]
+ Disable CPUID feature X for the kernel. See
+ include/asm-x86/cpufeature.h for the valid bit numbers.
+ Note the Linux specific bits are not necessarily
+ 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.
+
+ code_bytes [IA32/X86_64] How many bytes of object code to print
+ in an oops report.
Range: 0 - 8192
Default: 64
@@ -523,33 +549,34 @@ and is between 256 and 4096 characters. It is defined in the file
1 will print _a lot_ more information - normally
only useful to kernel developers.
- decnet= [HW,NET]
+ decnet.addr= [HW,NET]
Format: <area>[,<node>]
See also Documentation/networking/decnet.txt.
- default_blu= [VT]
+ 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.
- default_grn= [VT]
+ 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.
- default_red= [VT]
+ 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.
- default_utf8= [VT]
+ vt.default_utf8=
+ [VT]
Format=<0|1>
Set system-wide default UTF-8 mode for all tty's.
- Default is 0 and by setting to 1, it enables UTF-8
- mode for all newly opened or allocated terminals.
+ Default is 1, i.e. UTF-8 mode is enabled for all
+ newly opened terminals.
dhash_entries= [KNL]
Set number of hash buckets for dentry cache.
@@ -561,6 +588,12 @@ and is between 256 and 4096 characters. It is defined in the file
See drivers/char/README.epca and
Documentation/digiepca.txt.
+ disable_mtrr_trim [X86, Intel and AMD only]
+ 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.
+
dmasound= [HW,OSS] Sound subsystem buffers
dscc4.setup= [NET]
@@ -651,6 +684,10 @@ and is between 256 and 4096 characters. It is defined in the file
gamma= [HW,DRM]
+ gart_fix_e820= [X86_64] disable the fix e820 for K8 GART
+ Format: off | on
+ default: on
+
gdth= [HW,SCSI]
See header of drivers/scsi/gdth.c.
@@ -685,6 +722,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/isdn/README.HiSax.
hugepages= [HW,X86-32,IA-64] Maximal number of HugeTLB pages.
+ hugepagesz= [HW,IA-64,PPC] The size of the HugeTLB pages.
i8042.direct [HW] Put keyboard port into non-translated mode
i8042.dumbkbd [HW] Pretend that controller can only read data from
@@ -742,6 +780,9 @@ and is between 256 and 4096 characters. It is defined in the file
loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
as idle=poll.
+ ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
+ Claim all unknown PCI IDE storage controllers.
+
ignore_loglevel [KNL]
Ignore loglevel setting - this will print /all/
kernel messages to the console. Useful for debugging.
@@ -785,6 +826,16 @@ and is between 256 and 4096 characters. It is defined in the file
for translation below 32 bit and if not available
then look in the higher range.
+ io_delay= [X86-32,X86-64] I/O delay method
+ 0x80
+ Standard port 0x80 based delay
+ 0xed
+ Alternate port 0xed based delay (needed on some systems)
+ udelay
+ Simple two microseconds delay
+ none
+ No delay
+
io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in
arch/alpha/kernel/core_marvel.c.
@@ -882,6 +933,14 @@ and is between 256 and 4096 characters. It is defined in the file
lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer in
C2 power state.
+ 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
+ libata.dma=4 Compact Flash DMA only
+ Combinations also work, so libata.dma=3 enables DMA
+ for disks and CDROMs, but not CFs.
+
libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume
when set.
Format: <int>
@@ -1042,6 +1101,11 @@ and is between 256 and 4096 characters. It is defined in the file
Multi-Function General Purpose Timers on AMD Geode
platforms.
+ 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.
+
mga= [HW,DRM]
mousedev.tap_time=
@@ -1114,6 +1178,10 @@ and is between 256 and 4096 characters. It is defined in the file
of returning the full 64-bit number.
The default is to return 64-bit inode numbers.
+ nmi_debug= [KNL,AVR32] Specify one or more actions to take
+ when a NMI is triggered.
+ Format: [state][,regs][,debounce][,die]
+
nmi_watchdog= [KNL,BUGS=X86-32] Debugging features for SMP kernels
no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
@@ -1138,6 +1206,8 @@ and is between 256 and 4096 characters. It is defined in the file
nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
+ noefi [X86-32,X86-64] Disable EFI runtime services support.
+
noexec [IA-64]
noexec [X86-32,X86-64]
@@ -1148,6 +1218,8 @@ and is between 256 and 4096 characters. It is defined in the file
register save and restore. The kernel will only save
legacy floating-point registers on task switch.
+ noclflush [BUGS=X86] Don't use the CLFLUSH instruction
+
nohlt [BUGS=ARM]
no-hlt [BUGS=X86-32] Tells the kernel that the hlt
@@ -1492,14 +1564,17 @@ and is between 256 and 4096 characters. It is defined in the file
ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
See Documentation/ramdisk.txt.
- rcu.blimit= [KNL,BOOT] Set maximum number of finished
- RCU callbacks to process in one batch.
+ rcupdate.blimit= [KNL,BOOT]
+ Set maximum number of finished RCU callbacks to process
+ in one batch.
- rcu.qhimark= [KNL,BOOT] Set threshold of queued
+ rcupdate.qhimark= [KNL,BOOT]
+ Set threshold of queued
RCU callbacks over which batch limiting is disabled.
- rcu.qlowmark= [KNL,BOOT] Set threshold of queued
- RCU callbacks below which batch limiting is re-enabled.
+ rcupdate.qlowmark= [KNL,BOOT]
+ Set threshold of queued RCU callbacks below which
+ batch limiting is re-enabled.
rdinit= [KNL]
Format: <full_path>
@@ -1584,7 +1659,13 @@ and is between 256 and 4096 characters. It is defined in the file
Format: <vendor>:<model>:<flags>
(flags are integer value)
- scsi_logging= [SCSI]
+ scsi_logging_level= [SCSI] a bit mask of logging levels
+ See drivers/scsi/scsi_logging.h for bits. Also
+ settable via sysctl at dev.scsi.logging_level
+ (/proc/sys/dev/scsi/logging_level).
+ There is also a nice 'scsi_logging_level' script in the
+ S390-tools package, available for download at
+ http://www-128.ibm.com/developerworks/linux/linux390/s390-tools-1.5.4.html
scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are
discovered. async scans them in kernel threads,
@@ -1813,9 +1894,6 @@ and is between 256 and 4096 characters. It is defined in the file
st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
See Documentation/scsi/st.txt.
- st0x= [HW,SCSI]
- See header of drivers/scsi/seagate.c.
-
sti= [PARISC,HW]
Format: <num>
Set the STI (builtin display/keyboard on the HP-PARISC
@@ -1900,9 +1978,6 @@ and is between 256 and 4096 characters. It is defined in the file
tipar.delay= [HW,PPT]
Set inter-bit delay in microseconds (default 10).
- tmc8xx= [HW,SCSI]
- See header of drivers/scsi/seagate.c.
-
tmscsim= [HW,SCSI]
See comment before function dc390_setup() in
drivers/scsi/tmscsim.c.
@@ -1951,6 +2026,11 @@ and is between 256 and 4096 characters. It is defined in the file
vdso=1: enable VDSO (default)
vdso=0: disable VDSO mapping
+ vdso32= [X86-32,X86-64]
+ vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
+ vdso32=1: enable 32-bit VDSO (default)
+ vdso32=0: disable 32-bit VDSO mapping
+
vector= [IA-64,SMP]
vector=percpu: enable percpu vector domain