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-rw-r--r--Documentation/kernel-parameters.txt147
1 files changed, 118 insertions, 29 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 736d45602886..2b2407d9a6d0 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -54,9 +54,11 @@ parameter is applicable:
IMA Integrity measurement architecture is enabled.
IOSCHED More than one I/O scheduler is enabled.
IP_PNP IP DHCP, BOOTP, or RARP is enabled.
+ IPV6 IPv6 support is enabled.
ISAPNP ISA PnP code is enabled.
ISDN Appropriate ISDN support is enabled.
JOY Appropriate joystick support is enabled.
+ KGDB Kernel debugger support is enabled.
KVM Kernel Virtual Machine support is enabled.
LIBATA Libata driver is enabled
LP Printer support is enabled.
@@ -98,6 +100,7 @@ parameter is applicable:
SWSUSP Software suspend (hibernation) is enabled.
SUSPEND System suspend states are enabled.
FTRACE Function tracing enabled.
+ TPM TPM drivers are enabled.
TS Appropriate touchscreen support is enabled.
UMS USB Mass Storage support is enabled.
USB USB support is enabled.
@@ -142,14 +145,14 @@ and is between 256 and 4096 characters. It is defined in the file
acpi= [HW,ACPI,X86]
Advanced Configuration and Power Interface
- Format: { force | off | ht | strict | noirq | rsdt }
+ Format: { force | off | strict | noirq | rsdt }
force -- enable ACPI if default was off
off -- disable ACPI if default was on
noirq -- do not use ACPI for IRQ routing
- ht -- run only enough ACPI to enable Hyper Threading
strict -- Be less tolerant of platforms that are not
strictly ACPI specification compliant.
rsdt -- prefer RSDT over (default) XSDT
+ copy_dsdt -- copy DSDT to memory
See also Documentation/power/pm.txt, pci=noacpi
@@ -251,8 +254,8 @@ and is between 256 and 4096 characters. It is defined in the file
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.
+ nonvs prevents the kernel from saving/restoring the
+ ACPI NVS memory during suspend/hibernation and resume.
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).
@@ -286,9 +289,6 @@ and is between 256 and 4096 characters. It is defined in the file
advansys= [HW,SCSI]
See header of drivers/scsi/advansys.c.
- advwdt= [HW,WDT] Advantech WDT
- Format: <iostart>,<iostop>
-
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.
@@ -311,18 +311,20 @@ and is between 256 and 4096 characters. It is defined in the file
aic79xx= [HW,SCSI]
See Documentation/scsi/aic79xx.txt.
+ 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.
+
amd_iommu= [HW,X86-84]
Pass parameters to the AMD IOMMU driver in the system.
Possible values are:
- isolate - enable device isolation (each device, as far
- as possible, will get its own protection
- domain) [default]
- share - put every device behind one IOMMU into the
- same protection domain
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
+ off - do not initialize any AMD IOMMU found in
+ the system
amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
@@ -347,6 +349,9 @@ and is between 256 and 4096 characters. It is defined in the file
Change the amount of debugging information output
when initialising the APIC and IO-APIC components.
+ autoconf= [IPV6]
+ See Documentation/networking/ipv6.txt.
+
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
@@ -629,6 +634,12 @@ and is between 256 and 4096 characters. It is defined in the file
See drivers/char/README.epca and
Documentation/serial/digiepca.txt.
+ disable= [IPV6]
+ See Documentation/networking/ipv6.txt.
+
+ disable_ipv6= [IPV6]
+ See Documentation/networking/ipv6.txt.
+
disable_mtrr_cleanup [X86]
The kernel tries to adjust MTRR layout from continuous
to discrete, to make X server driver able to add WB
@@ -698,6 +709,12 @@ and is between 256 and 4096 characters. It is defined in the file
The VGA output is eventually overwritten by the real
console.
+ ekgdboc= [X86,KGDB] Allow early kernel console debugging
+ ekgdboc=kbd
+
+ This is desgined to be used in conjunction with
+ the boot argument: earlyprintk=vga
+
eata= [HW,SCSI]
edd= [EDD]
@@ -740,13 +757,14 @@ and is between 256 and 4096 characters. It is defined in the file
Default value is 0.
Value can be changed at runtime via /selinux/enforce.
+ erst_disable [ACPI]
+ Disable Error Record Serialization Table (ERST)
+ support.
+
ether= [HW,NET] Ethernet cards parameters
This option is obsoleted by the "netdev=" option, which
has equivalent usage. See its documentation for details.
- eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
- Format: <io>[,<irq>]
-
failslab=
fail_page_alloc=
fail_make_request=[KNL]
@@ -774,8 +792,12 @@ and is between 256 and 4096 characters. It is defined in the file
as early as possible in order to facilitate early
boot debugging.
- ftrace_dump_on_oops
+ ftrace_dump_on_oops[=orig_cpu]
[FTRACE] will dump the trace buffers on oops.
+ 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.
ftrace_filter=[function-list]
[FTRACE] Limit the functions traced by the function
@@ -833,6 +855,11 @@ and is between 256 and 4096 characters. It is defined in the file
hd= [EIDE] (E)IDE hard drive subsystem geometry
Format: <cyl>,<head>,<sect>
+ hest_disable [ACPI]
+ Disable Hardware Error Source Table (HEST) support;
+ corresponding firmware-first mode error processing
+ logic will be disabled.
+
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
@@ -1102,10 +1129,26 @@ 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.
- kgdboc= [HW] kgdb over consoles.
- Requires a tty driver that supports console polling.
- (only serial supported for now)
- Format: <serial_device>[,baud]
+ 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.
+
+ 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]
+
+ kgdbwait [KGDB] Stop kernel execution and enter the
+ kernel debugger at the earliest opportunity.
kmac= [MIPS] korina ethernet MAC address.
Configure the RouterBoard 532 series on-chip
@@ -1184,7 +1227,7 @@ and is between 256 and 4096 characters. It is defined in the file
libata.force= [LIBATA] Force configurations. The format is comma
separated list of "[ID:]VAL" where ID is
- PORT[:DEVICE]. PORT and DEVICE are decimal numbers
+ PORT[.DEVICE]. PORT and DEVICE are decimal numbers
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
@@ -1217,10 +1260,12 @@ and is between 256 and 4096 characters. It is defined in the file
* nohrst, nosrst, norst: suppress hard, soft
and both resets.
+ * dump_id: dump IDENTIFY data.
+
If there are multiple matching configurations changing
the same attribute, the last one is used.
- lmb=debug [KNL] Enable lmb debug messages.
+ memblock=debug [KNL] Enable memblock debug messages.
load_ramdisk= [RAM] List of ramdisks to load from floppy
See Documentation/blockdev/ramdisk.txt.
@@ -1729,6 +1774,9 @@ and is between 256 and 4096 characters. It is defined in the file
nomfgpt [X86-32] Disable Multi-Function General Purpose
Timer usage (for AMD Geode machines).
+ nopat [X86] Disable PAT (page attribute table extension of
+ pagetables) support.
+
norandmaps Don't use address space randomization. Equivalent to
echo 0 > /proc/sys/kernel/randomize_va_space
@@ -1772,6 +1820,12 @@ and is between 256 and 4096 characters. It is defined in the file
purges which is reported from either PAL_VM_SUMMARY or
SAL PALO.
+ 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
+
nr_uarts= [SERIAL] maximum number of UARTs to be registered.
numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
@@ -1939,8 +1993,12 @@ and is between 256 and 4096 characters. It is defined in the file
IRQ routing is enabled.
noacpi [X86] Do not use ACPI for IRQ routing
or for PCI scanning.
- use_crs [X86] Use _CRS for PCI resource
- allocation.
+ 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.
routeirq Do IRQ routing for all PCI devices.
This is normally done in pci_enable_device(),
so this option is a temporary workaround
@@ -1989,6 +2047,16 @@ and is between 256 and 4096 characters. It is defined in the file
force Enable ASPM even on devices that claim not to support it.
WARNING: Forcing ASPM on may cause system lockups.
+ pcie_pme= [PCIE,PM] Native PCIe PME signaling options:
+ Format: {auto|force}[,nomsi]
+ auto Use native PCIe PME signaling if the BIOS allows the
+ kernel to control PCIe config registers of root ports.
+ force Use native PCIe PME signaling even if the BIOS refuses
+ to allow the kernel to control the relevant PCIe config
+ registers.
+ nomsi Do not use MSI for native PCIe PME signaling (this makes
+ all PCIe root ports use INTx for everything).
+
pcmv= [HW,PCMCIA] BadgePAD 4
pd. [PARIDE]
@@ -2205,9 +2273,6 @@ and is between 256 and 4096 characters. It is defined in the file
sched_debug [KNL] Enables verbose scheduler debug messages.
- sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
- Format: <io>[,<timeout>[,<isapnp>]]
-
scsi_debug_*= [SCSI]
See drivers/scsi/scsi_debug.c.
@@ -2579,6 +2644,15 @@ and is between 256 and 4096 characters. It is defined in the file
tp720= [HW,PS2]
+ 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.
+
trace_buf_size=nn[KMG]
[FTRACE] will set tracing buffer size.
@@ -2694,6 +2768,13 @@ and is between 256 and 4096 characters. It is defined in the file
medium is write-protected).
Example: quirks=0419:aaf5:rl,0421:0433:rc
+ userpte=
+ [X86] Flags controlling user PTE allocations.
+
+ nohigh = do not allocate PTE pages in
+ HIGHMEM regardless of setting
+ of CONFIG_HIGHPTE.
+
vdso= [X86,SH]
vdso=2: enable compat VDSO (default with COMPAT_VDSO)
vdso=1: enable VDSO (default)
@@ -2780,13 +2861,21 @@ and is between 256 and 4096 characters. It is defined in the file
wd7000= [HW,SCSI]
See header of drivers/scsi/wd7000.c.
- wdt= [WDT] Watchdog
- See Documentation/watchdog/wdt.txt.
+ 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.
x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
default x2apic cluster mode on platforms
supporting x2apic.
+ x86_mrst_timer= [X86-32,APBT]
+ Choose timer option for x86 Moorestown MID platform.
+ Two valid options are apbt timer only and lapic timer
+ plus one apbt timer for broadcast timer.
+ x86_mrst_timer=apbt_only | lapic_and_apbt
+
xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
xd_geo= See header of drivers/block/xd.c.