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-rw-r--r--Documentation/kernel-parameters.txt342
1 files changed, 47 insertions, 295 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 2b2407d9a6d..2c85c0692b0 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -73,7 +73,6 @@ parameter is applicable:
MTD MTD (Memory Technology Device) support is enabled.
NET Appropriate network support is enabled.
NUMA NUMA support is enabled.
- GENERIC_TIME The generic timeofday code is enabled.
NFS Appropriate NFS support is enabled.
OSS OSS sound support is enabled.
PV_OPS A paravirtualized kernel is enabled.
@@ -89,10 +88,11 @@ parameter is applicable:
RAM RAM disk support is enabled.
S390 S390 architecture is enabled.
SCSI Appropriate SCSI support is enabled.
- A lot of drivers has their options described inside of
- Documentation/scsi/.
+ A lot of drivers have their options described inside
+ the Documentation/scsi/ sub-directory.
SECURITY Different security models are enabled.
SELINUX SELinux support is enabled.
+ APPARMOR AppArmor support is enabled.
SERIAL Serial support is enabled.
SH SuperH architecture is enabled.
SMP The kernel is an SMP kernel.
@@ -115,6 +115,7 @@ parameter is applicable:
More X86-64 boot options can be found in
Documentation/x86/x86_64/boot-options.txt .
X86 Either 32bit or 64bit x86 (same as X86-32+X86-64)
+ XEN Xen support is enabled
In addition, the following text indicates that the option:
@@ -280,36 +281,17 @@ and is between 256 and 4096 characters. It is defined in the file
no: ACPI OperationRegions are not marked as reserved,
no further checks are performed.
- ad1848= [HW,OSS]
- Format: <io>,<irq>,<dma>,<dma2>,<type>
-
add_efi_memmap [EFI; X86] Include EFI memory map in
kernel's map of available physical RAM.
- advansys= [HW,SCSI]
- See header of drivers/scsi/advansys.c.
-
- aedsp16= [HW,OSS] Audio Excel DSP 16
- Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
- See also header of sound/oss/aedsp16.c.
-
agp= [AGP]
{ off | try_unsupported }
off: disable AGP support
try_unsupported: try to drive unsupported chipsets
(may crash computer or cause data corruption)
- aha152x= [HW,SCSI]
- See Documentation/scsi/aha152x.txt.
-
- aha1542= [HW,SCSI]
- Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
-
- aic7xxx= [HW,SCSI]
- See Documentation/scsi/aic7xxx.txt.
-
- aic79xx= [HW,SCSI]
- See Documentation/scsi/aic79xx.txt.
+ ALSA [HW,ALSA]
+ See Documentation/sound/alsa/alsa-parameters.txt
alignment= [KNL,ARM]
Allow the default userspace alignment fault handler
@@ -371,8 +353,6 @@ and is between 256 and 4096 characters. It is defined in the file
atarimouse= [HW,MOUSE] Atari Mouse
- atascsi= [HW,SCSI] Atari SCSI
-
atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
EzKey and similar keyboards
@@ -422,10 +402,6 @@ and is between 256 and 4096 characters. It is defined in the file
bttv.pll= See Documentation/video4linux/bttv/Insmod-options
bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
- BusLogic= [HW,SCSI]
- See drivers/scsi/BusLogic.c, comment before function
- BusLogic_ParseDriverOptions().
-
c101= [NET] Moxa C101 synchronous serial card
cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
@@ -468,7 +444,7 @@ and is between 256 and 4096 characters. It is defined in the file
clocksource is not available, it defaults to PIT.
Format: { pit | tsc | cyclone | pmtmr }
- clocksource= [GENERIC_TIME] Override the default clocksource
+ clocksource= Override the default clocksource
Format: <string>
Override the default clocksource and use the clocksource
with the name specified.
@@ -655,8 +631,6 @@ and is between 256 and 4096 characters. It is defined in the file
Disable PIN 1 of APIC timer
Can be useful to work around chipset bugs.
- dmasound= [HW,OSS] Sound subsystem buffers
-
dma_debug=off If the kernel is compiled with DMA_API_DEBUG support,
this option disables the debugging code at boot.
@@ -676,8 +650,6 @@ and is between 256 and 4096 characters. It is defined in the file
dscc4.setup= [NET]
- dtc3181e= [HW,SCSI]
-
dynamic_printk Enables pr_debug()/dev_dbg() calls if
CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled.
These can also be switched on/off via
@@ -686,8 +658,11 @@ and is between 256 and 4096 characters. It is defined in the file
earlycon= [KNL] Output early console device and options.
uart[8250],io,<addr>[,options]
uart[8250],mmio,<addr>[,options]
+ uart[8250],mmio32,<addr>[,options]
Start an early, polled-mode console on the 8250/16550
UART at the specified I/O port or MMIO address.
+ MMIO inter-register address stride is either 8bit (mmio)
+ or 32bit (mmio32).
The options are the same as for ttyS, above.
earlyprintk= [X86,SH,BLACKFIN]
@@ -715,8 +690,6 @@ and is between 256 and 4096 characters. It is defined in the file
This is desgined to be used in conjunction with
the boot argument: earlyprintk=vga
- eata= [HW,SCSI]
-
edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
@@ -772,12 +745,6 @@ and is between 256 and 4096 characters. It is defined in the file
Format: <interval>,<probability>,<space>,<times>
See also /Documentation/fault-injection/.
- fd_mcs= [HW,SCSI]
- See header of drivers/scsi/fd_mcs.c.
-
- fdomain= [HW,SCSI]
- See header of drivers/scsi/fdomain.c.
-
floppy= [HW]
See Documentation/blockdev/floppy.txt.
@@ -837,14 +804,9 @@ and is between 256 and 4096 characters. It is defined in the file
When zero, profiling data is discarded and associated
debugfs files are removed at module unload time.
- gdth= [HW,SCSI]
- See header of drivers/scsi/gdth.c.
-
gpt [EFI] Forces disk with valid GPT signature but
invalid Protective MBR to be treated as GPT.
- gvp11= [HW,SCSI]
-
hashdist= [KNL,NUMA] Large hashes allocated during boot
are distributed across NUMA nodes. Defaults on
for 64bit NUMA, off otherwise.
@@ -917,9 +879,6 @@ and is between 256 and 4096 characters. It is defined in the file
controller
i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
controllers
- i8042.panicblink=
- [HW] Frequency with which keyboard LEDs should blink
- when kernel panics (default is 0.5 sec)
i8042.reset [HW] Reset the controller during init and cleanup
i8042.unlock [HW] Unlock (ignore) the keylock
@@ -936,9 +895,6 @@ and is between 256 and 4096 characters. It is defined in the file
i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
capability is set.
- ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
- See Documentation/mca.txt.
-
icn= [HW,ISDN]
Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
@@ -988,9 +944,6 @@ and is between 256 and 4096 characters. It is defined in the file
programs exec'd, files mmap'd for exec, and all files
opened for read by uid=0.
- in2000= [HW,SCSI]
- See header of drivers/scsi/in2000.c.
-
init= [KNL]
Format: <full_path>
Run specified binary instead of /sbin/init as init
@@ -1028,6 +981,12 @@ and is between 256 and 4096 characters. It is defined in the file
result in a hardware IOTLB flush operation as opposed
to batching them for performance.
+ intremap= [X86-64, Intel-IOMMU]
+ Format: { on (default) | off | nosid }
+ on enable Interrupt Remapping (default)
+ off disable Interrupt Remapping
+ nosid disable Source ID checking
+
inttest= [IA64]
iomem= Disable strict checking of access to MMIO memory
@@ -1068,9 +1027,6 @@ and is between 256 and 4096 characters. It is defined in the file
See comment before ip2_setup() in
drivers/char/ip2/ip2base.c.
- ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
- See header of drivers/scsi/ips.c.
-
irqfixup [HW]
When an interrupt is not handled search all handlers
for it. Intended to get systems with badly broken
@@ -1143,9 +1099,12 @@ and is between 256 and 4096 characters. It is defined in the file
kgdboc= [KGDB,HW] kgdb over consoles.
Requires a tty driver that supports console polling,
or a supported polling keyboard driver (non-usb).
- Serial only format: <serial_device>[,baud]
- keyboard only format: kbd
- keyboard and serial format: kbd,<serial_device>[,baud]
+ 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]
kgdbwait [KGDB] Stop kernel execution and enter the
kernel debugger at the earliest opportunity.
@@ -1343,9 +1302,6 @@ and is between 256 and 4096 characters. It is defined in the file
ltpc= [NET]
Format: <io>,<irq>,<dma>
- mac5380= [HW,SCSI] Format:
- <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
-
machvec= [IA64] Force the use of a particular machine-vector
(machvec) in a generic kernel.
Example: machvec=hpzx1_swiotlb
@@ -1367,13 +1323,6 @@ and is between 256 and 4096 characters. It is defined in the file
be mounted
Format: <1-256>
- max_luns= [SCSI] Maximum number of LUNs to probe.
- Should be between 1 and 2^32-1.
-
- max_report_luns=
- [SCSI] Maximum number of LUNs received.
- Should be between 1 and 16384.
-
mcatest= [IA-64]
mce [X86-32] Machine Check Exception
@@ -1523,9 +1472,6 @@ and is between 256 and 4096 characters. It is defined in the file
that the amount of memory usable for all allocations
is not too small.
- mpu401= [HW,OSS]
- Format: <io>,<irq>
-
MTD_Partition= [MTD]
Format: <name>,<region-number>,<size>,<offset>
@@ -1573,19 +1519,6 @@ and is between 256 and 4096 characters. It is defined in the file
n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
- NCR_D700= [HW,SCSI]
- See header of drivers/scsi/NCR_D700.c.
-
- ncr5380= [HW,SCSI]
-
- ncr53c400= [HW,SCSI]
-
- ncr53c400a= [HW,SCSI]
-
- ncr53c406a= [HW,SCSI]
-
- ncr53c8xx= [HW,SCSI]
-
netdev= [NET] Network devices parameters
Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
Note that mem_start is often overloaded to mean
@@ -1597,8 +1530,7 @@ and is between 256 and 4096 characters. It is defined in the file
[NETFILTER] Enable connection tracking flow accounting
0 to disable accounting
1 to enable accounting
- Default value depends on CONFIG_NF_CT_ACCT that is
- going to be removed in 2.6.29.
+ Default value is 0.
nfsaddrs= [NFS]
See Documentation/filesystems/nfs/nfsroot.txt.
@@ -1755,6 +1687,7 @@ and is between 256 and 4096 characters. It is defined in the file
nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
remapping.
+ [Deprecated - use intremap=off]
nointroute [IA-64]
@@ -1812,6 +1745,8 @@ and is between 256 and 4096 characters. It is defined in the file
nousb [USB] Disable the USB subsystem
+ nowatchdog [KNL] Disable the lockup detector.
+
nowb [ARM]
nox2apic [X86-64,APIC] Do not enable x2APIC mode.
@@ -1849,9 +1784,6 @@ and is between 256 and 4096 characters. It is defined in the file
For example, to override I2C bus2:
omap_mux=i2c2_scl.i2c2_scl=0x100,i2c2_sda.i2c2_sda=0x100
- opl3= [HW,OSS]
- Format: <io>
-
oprofile.timer= [HW]
Use timer interrupt instead of performance counters
@@ -1863,9 +1795,8 @@ and is between 256 and 4096 characters. It is defined in the file
perfmon on Intel CPUs instead of the
CPU specific event set.
- osst= [HW,SCSI] SCSI Tape Driver
- Format: <buffer_size>,<write_threshold>
- See also Documentation/scsi/st.txt.
+ OSS [HW,OSS]
+ See Documentation/sound/oss/oss-parameters.txt
panic= [KNL] Kernel behaviour on panic
Format: <timeout>
@@ -1899,12 +1830,6 @@ and is between 256 and 4096 characters. It is defined in the file
Currently this function knows 686a and 8231 chips.
Format: [spp|ps2|epp|ecp|ecpepp]
- pas2= [HW,OSS] Format:
- <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
-
- pas16= [HW,SCSI]
- See header of drivers/scsi/pas16.c.
-
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
@@ -1970,6 +1895,8 @@ and is between 256 and 4096 characters. It is defined in the file
norom [X86] Do not assign address space to
expansion ROMs that do not already have
BIOS assigned address ranges.
+ nobar [X86] Do not assign address space to the
+ BARs that weren't assigned by the BIOS.
irqmask=0xMMMM [X86] Set a bit mask of IRQs allowed to be
assigned automatically to PCI devices. You can
make the kernel exclude IRQs of your ISA cards
@@ -2171,10 +2098,6 @@ and is between 256 and 4096 characters. It is defined in the file
[HW,MOUSE] Controls Logitech smartscroll autorepeat.
0 = disabled, 1 = enabled (default).
- pss= [HW,OSS] Personal Sound System (ECHO ESC614)
- Format:
- <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
-
pt. [PARIDE]
See Documentation/blockdev/paride.txt.
@@ -2273,30 +2196,6 @@ and is between 256 and 4096 characters. It is defined in the file
sched_debug [KNL] Enables verbose scheduler debug messages.
- scsi_debug_*= [SCSI]
- See drivers/scsi/scsi_debug.c.
-
- scsi_default_dev_flags=
- [SCSI] SCSI default device flags
- Format: <integer>
-
- scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
- Format: <vendor>:<model>:<flags>
- (flags are integer value)
-
- 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,
- allowing boot to proceed. none ignores them, expecting
- user space to do the scan.
-
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
@@ -2312,6 +2211,13 @@ and is between 256 and 4096 characters. It is defined in the file
If enabled at boot time, /selinux/disable can be used
later to disable prior to initial policy load.
+ 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.
+
serialnumber [BUGS=X86-32]
shapers= [NET]
@@ -2323,9 +2229,6 @@ and is between 256 and 4096 characters. It is defined in the file
The parameter means the number of CPUs to show,
for example 1 means boot CPU only.
- sim710= [SCSI,HW]
- See header of drivers/scsi/sim710.c.
-
simeth= [IA-64]
simscsi=
@@ -2383,128 +2286,6 @@ and is between 256 and 4096 characters. It is defined in the file
1: Fast pin select (default)
2: ATC IRMode
- snd-ad1816a= [HW,ALSA]
-
- snd-ad1848= [HW,ALSA]
-
- snd-ali5451= [HW,ALSA]
-
- snd-als100= [HW,ALSA]
-
- snd-als4000= [HW,ALSA]
-
- snd-azt2320= [HW,ALSA]
-
- snd-cmi8330= [HW,ALSA]
-
- snd-cmipci= [HW,ALSA]
-
- snd-cs4231= [HW,ALSA]
-
- snd-cs4232= [HW,ALSA]
-
- snd-cs4236= [HW,ALSA]
-
- snd-cs4281= [HW,ALSA]
-
- snd-cs46xx= [HW,ALSA]
-
- snd-dt019x= [HW,ALSA]
-
- snd-dummy= [HW,ALSA]
-
- snd-emu10k1= [HW,ALSA]
-
- snd-ens1370= [HW,ALSA]
-
- snd-ens1371= [HW,ALSA]
-
- snd-es968= [HW,ALSA]
-
- snd-es1688= [HW,ALSA]
-
- snd-es18xx= [HW,ALSA]
-
- snd-es1938= [HW,ALSA]
-
- snd-es1968= [HW,ALSA]
-
- snd-fm801= [HW,ALSA]
-
- snd-gusclassic= [HW,ALSA]
-
- snd-gusextreme= [HW,ALSA]
-
- snd-gusmax= [HW,ALSA]
-
- snd-hdsp= [HW,ALSA]
-
- snd-ice1712= [HW,ALSA]
-
- snd-intel8x0= [HW,ALSA]
-
- snd-interwave= [HW,ALSA]
-
- snd-interwave-stb=
- [HW,ALSA]
-
- snd-korg1212= [HW,ALSA]
-
- snd-maestro3= [HW,ALSA]
-
- snd-mpu401= [HW,ALSA]
-
- snd-mtpav= [HW,ALSA]
-
- snd-nm256= [HW,ALSA]
-
- snd-opl3sa2= [HW,ALSA]
-
- snd-opti92x-ad1848=
- [HW,ALSA]
-
- snd-opti92x-cs4231=
- [HW,ALSA]
-
- snd-opti93x= [HW,ALSA]
-
- snd-pmac= [HW,ALSA]
-
- snd-rme32= [HW,ALSA]
-
- snd-rme96= [HW,ALSA]
-
- snd-rme9652= [HW,ALSA]
-
- snd-sb8= [HW,ALSA]
-
- snd-sb16= [HW,ALSA]
-
- snd-sbawe= [HW,ALSA]
-
- snd-serial= [HW,ALSA]
-
- snd-sgalaxy= [HW,ALSA]
-
- snd-sonicvibes= [HW,ALSA]
-
- snd-sun-amd7930=
- [HW,ALSA]
-
- snd-sun-cs4231= [HW,ALSA]
-
- snd-trident= [HW,ALSA]
-
- snd-usb-audio= [HW,ALSA,USB]
-
- snd-via82xx= [HW,ALSA]
-
- snd-virmidi= [HW,ALSA]
-
- snd-wavefront= [HW,ALSA]
-
- snd-ymfpci= [HW,ALSA]
-
softlockup_panic=
[KNL] Should the soft-lockup detector generate panics.
@@ -2519,12 +2300,6 @@ and is between 256 and 4096 characters. It is defined in the file
spia_pedr=
spia_peddr=
- sscape= [HW,OSS]
- Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
-
- st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
- See Documentation/scsi/st.txt.
-
stacktrace [FTRACE]
Enabled the stack tracer on boot up.
@@ -2582,18 +2357,12 @@ and is between 256 and 4096 characters. It is defined in the file
switches= [HW,M68k]
- sym53c416= [HW,SCSI]
- See header of drivers/scsi/sym53c416.c.
-
sysrq_always_enabled
[KNL]
Ignore sysrq setting - this boot parameter will
neutralize any effect of /proc/sys/kernel/sysrq.
Useful for debugging.
- t128= [HW,SCSI]
- See header of drivers/scsi/t128.c.
-
tdfx= [HW,DRM]
test_suspend= [SUSPEND]
@@ -2630,10 +2399,6 @@ and is between 256 and 4096 characters. It is defined in the file
<deci-seconds>: poll all this frequency
0: no polling (default)
- tmscsim= [HW,SCSI]
- See comment before function dc390_setup() in
- drivers/scsi/tmscsim.c.
-
topology= [S390]
Format: {off | on}
Specify if the kernel should make use of the cpu
@@ -2661,10 +2426,6 @@ and is between 256 and 4096 characters. It is defined in the file
to facilitate early boot debugging.
See also Documentation/trace/events.txt
- trix= [HW,OSS] MediaTrix AudioTrix Pro
- Format:
- <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
-
tsc= Disable clocksource-must-verify flag for TSC.
Format: <string>
[x86] reliable: mark tsc clocksource as reliable, this
@@ -2678,15 +2439,6 @@ and is between 256 and 4096 characters. It is defined in the file
<port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
See also Documentation/input/joystick-parport.txt
- u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
- See header of drivers/scsi/u14-34f.c.
-
- uart401= [HW,OSS]
- Format: <io>,<irq>
-
- uart6850= [HW,OSS]
- Format: <io>,<irq>
-
uhash_entries= [KNL,NET]
Set number of hash buckets for UDP/UDP-Lite connections
@@ -2852,15 +2604,6 @@ and is between 256 and 4096 characters. It is defined in the file
overridden by individual drivers. 0 will hide
cursors, 1 will display them.
- waveartist= [HW,OSS]
- Format: <io>,<irq>,<dma>,<dma2>
-
- wd33c93= [HW,SCSI]
- See header of drivers/scsi/wd33c93.c.
-
- wd7000= [HW,SCSI]
- See header of drivers/scsi/wd7000.c.
-
watchdog timers [HW,WDT] For information on watchdog timers,
see Documentation/watchdog/watchdog-parameters.txt
or other driver-specific files in the
@@ -2879,6 +2622,16 @@ and is between 256 and 4096 characters. It is defined in the file
xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
xd_geo= See header of drivers/block/xd.c.
+ 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)
+ ignore -- continue loading the Xen platform PCI driver even
+ if the version check failed
+
xirc2ps_cs= [NET,PCMCIA]
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
@@ -2887,5 +2640,4 @@ ______________________________________________________________________
TODO:
- Add documentation for ALSA options.
Add more DRM drivers.