summaryrefslogtreecommitdiffstats
path: root/Documentation/kernel-parameters.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/kernel-parameters.txt')
-rw-r--r--Documentation/kernel-parameters.txt116
1 files changed, 96 insertions, 20 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e58c91ca802..0bf8a882ee9 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -17,6 +17,12 @@ are specified on the kernel command line with the module name plus
usbcore.blinkenlights=1
+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
+
+
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
@@ -50,7 +56,6 @@ parameter is applicable:
ISAPNP ISA PnP code is enabled.
ISDN Appropriate ISDN support is enabled.
JOY Appropriate joystick support is enabled.
- KMEMTRACE kmemtrace is enabled.
LIBATA Libata driver is enabled
LP Printer support is enabled.
LOOP Loopback device support is enabled.
@@ -231,6 +236,35 @@ and is between 256 and 4096 characters. It is defined in the file
power state again in power transition.
1 : disable the power state check
+ acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
+ Format: { level | edge | high | low }
+
+ acpi_serialize [HW,ACPI] force serialization of AML methods
+
+ 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,
+ old_ordering, s4_nonvs }
+ 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).
+ s4_nonvs prevents the kernel from saving/restoring the
+ ACPI NVS memory during hibernation.
+
+ 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
+
acpi_enforce_resources= [ACPI]
{ strict | lax | no }
Check for resource conflicts between native drivers
@@ -250,6 +284,9 @@ and is between 256 and 4096 characters. It is defined in the file
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.
@@ -291,11 +328,6 @@ and is between 256 and 4096 characters. It is defined in the file
flushed before they will be reused, which
is a lot of faster
- amd_iommu_size= [HW,X86-64]
- Define the size of the aperture for the AMD IOMMU
- driver. Possible values are:
- '32M', '64M' (default), '128M', '256M', '512M', '1G'
-
amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
Format: <a>,<b>
@@ -313,7 +345,7 @@ and is between 256 and 4096 characters. It is defined in the file
not play well with APC CPU idle - disable it if you have
APC and your system crashes randomly.
- apic= [APIC,i386] Advanced Programmable Interrupt Controller
+ apic= [APIC,X86-32] Advanced Programmable Interrupt Controller
Change the output verbosity whilst booting
Format: { quiet (default) | verbose | debug }
Change the amount of debugging information output
@@ -608,6 +640,13 @@ and is between 256 and 4096 characters. It is defined in the file
DMA-API debugging code disables itself because the
architectural default is too low.
+ 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.
+
dscc4.setup= [NET]
dtc3181e= [HW,SCSI]
@@ -670,7 +709,7 @@ and is between 256 and 4096 characters. It is defined in the file
to discrete, to make X server driver able to add WB
entry later. This parameter enables that.
- enable_timer_pin_1 [i386,x86-64]
+ enable_timer_pin_1 [X86]
Enable PIN 1 of APIC timer
Can be useful to work around chipset bugs
(in particular on some ATI chipsets).
@@ -714,12 +753,25 @@ and is between 256 and 4096 characters. It is defined in the file
ia64_pal_cache_flush instead of SAL_CACHE_FLUSH.
ftrace=[tracer]
- [ftrace] will set and start the specified tracer
+ [FTRACE] will set and start the specified tracer
as early as possible in order to facilitate early
boot debugging.
ftrace_dump_on_oops
- [ftrace] will dump the trace buffers on oops.
+ [FTRACE] will dump the trace buffers on oops.
+
+ 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
+ tracing directory.
+
+ 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.
gamecon.map[2|3]=
[HW,JOY] Multisystem joystick and NES/SNES/PSX pad
@@ -743,7 +795,7 @@ and is between 256 and 4096 characters. It is defined in the file
hashdist= [KNL,NUMA] Large hashes allocated during boot
are distributed across NUMA nodes. Defaults on
- for IA-64, off otherwise.
+ for 64bit NUMA, off otherwise.
Format: 0 | 1 (for off | on)
hcl= [IA-64] SGI's Hardware Graph compatibility layer
@@ -873,6 +925,12 @@ and is between 256 and 4096 characters. It is defined in the file
Formt: { "sha1" | "md5" }
default: "sha1"
+ 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.
+
in2000= [HW,SCSI]
See header of drivers/scsi/in2000.c.
@@ -1013,15 +1071,6 @@ and is between 256 and 4096 characters. It is defined in the file
use the HighMem zone if it exists, and the Normal
zone if it does not.
- kmemtrace.enable= [KNL,KMEMTRACE] Format: { yes | no }
- Controls whether kmemtrace is enabled
- at boot-time.
-
- kmemtrace.subbufs=n [KNL,KMEMTRACE] Overrides the number of
- subbufs kmemtrace's relay channel has. Set this
- higher than default (KMEMTRACE_N_SUBBUFS in code) if
- you experience buffer overruns.
-
kgdboc= [HW] kgdb over consoles.
Requires a tty driver that supports console polling.
(only serial suported for now)
@@ -1031,6 +1080,10 @@ and is between 256 and 4096 characters. It is defined in the file
Configure the RouterBoard 532 series on-chip
Ethernet adapter MAC address.
+ kmemleak= [KNL] Boot-time kmemleak enable/disable
+ Valid arguments: on, off
+ Default: on
+
kstack=N [X86] Print N words from the kernel stack
in oops dumps.
@@ -1494,6 +1547,10 @@ 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.
+ 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.
+
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.
@@ -1530,6 +1587,9 @@ and is between 256 and 4096 characters. It is defined in the file
noinitrd [RAM] Tells the kernel not to load any configured
initial RAM disk.
+ nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
+ remapping.
+
nointroute [IA-64]
nojitter [IA64] Disables jitter checking for ITC timers.
@@ -1585,6 +1645,8 @@ and is between 256 and 4096 characters. It is defined in the file
nowb [ARM]
+ nox2apic [X86-64,APIC] Do not enable x2APIC mode.
+
nptcg= [IA64] Override max number of concurrent global TLB
purges which is reported from either PAL_VM_SUMMARY or
SAL PALO.
@@ -1613,6 +1675,14 @@ and is between 256 and 4096 characters. It is defined in the file
oprofile.timer= [HW]
Use timer interrupt instead of performance counters
+ 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.
+ Format: { archperfmon }
+ archperfmon: [X86] Force use of architectural
+ 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.
@@ -1835,6 +1905,12 @@ and is between 256 and 4096 characters. It is defined in the file
autoconfiguration.
Ranges are in pairs (memory base and size).
+ 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>....
+
print-fatal-signals=
[KNL] debug: print fatal signals
print-fatal-signals=1: print segfault info to