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-rw-r--r--Documentation/kernel-parameters.txt191
1 files changed, 166 insertions, 25 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e07c432c731..2443f5bb436 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -87,7 +87,8 @@ parameter is applicable:
SH SuperH architecture is enabled.
SMP The kernel is an SMP kernel.
SPARC Sparc architecture is enabled.
- SWSUSP Software suspend is enabled.
+ SWSUSP Software suspend (hibernation) is enabled.
+ SUSPEND System suspend states are enabled.
TS Appropriate touchscreen support is enabled.
USB USB support is enabled.
USBHID USB Human Interface Device support is enabled.
@@ -147,10 +148,16 @@ and is between 256 and 4096 characters. It is defined in the file
default: 0
acpi_sleep= [HW,ACPI] Sleep options
- Format: { s3_bios, s3_mode, s3_beep }
+ Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, old_ordering }
See Documentation/power/video.txt for 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, wrt putting devices into low power
+ states, to be enforced (the ACPI 2.0 ordering of _PTS is
+ used by default).
acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Format: { level | edge | high | low }
@@ -271,6 +278,22 @@ and is between 256 and 4096 characters. It is defined in the file
aic79xx= [HW,SCSI]
See Documentation/scsi/aic79xx.txt.
+ 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)
+ 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
+
+ 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>
@@ -295,7 +318,7 @@ and is between 256 and 4096 characters. It is defined in the file
when initialising the APIC and IO-APIC components.
apm= [APM] Advanced Power Management
- See header of arch/i386/kernel/apm.c.
+ See header of arch/x86/kernel/apm_32.c.
arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
Format: <io>,<irq>,<nodeID>
@@ -347,6 +370,8 @@ and is between 256 and 4096 characters. It is defined in the file
no delay (0).
Format: integer
+ bootmem_debug [KNL] Enable bootmem allocator debug messages.
+
bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
bttv.radio= Most important insmod options are available as
kernel args too.
@@ -443,12 +468,6 @@ and is between 256 and 4096 characters. It is defined in the file
Range: 0 - 8192
Default: 64
- disable_8254_timer
- enable_8254_timer
- [IA32/X86_64] Disable/Enable interrupt 0 timer routing
- over the 8254 in addition to over the IO-APIC. The
- kernel tries to set a sensible default.
-
hpet= [X86-32,HPET] option to control HPET usage
Format: { enable (default) | disable | force }
disable: disable HPET and use PIT instead
@@ -560,6 +579,8 @@ and is between 256 and 4096 characters. It is defined in the file
debug_objects [KNL] Enable object debugging
+ debugpat [X86] Enable PAT debugging
+
decnet.addr= [HW,NET]
Format: <area>[,<node>]
See also Documentation/networking/decnet.txt.
@@ -599,6 +620,29 @@ and is between 256 and 4096 characters. It is defined in the file
See drivers/char/README.epca and
Documentation/digiepca.txt.
+ disable_mtrr_cleanup [X86]
+ 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/disables that.
+
+ mtrr_chunk_size=nn[KMG] [X86]
+ used for mtrr cleanup. It is largest continous chunk
+ 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.
+
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
@@ -614,11 +658,12 @@ and is between 256 and 4096 characters. It is defined in the file
earlyprintk= [X86-32,X86-64,SH,BLACKFIN]
earlyprintk=vga
earlyprintk=serial[,ttySn[,baudrate]]
+ earlyprintk=dbgp
Append ",keep" to not disable it when the real console
takes over.
- Only vga or serial at a time, not both.
+ Only vga or serial or usb debug port at a time.
Currently only ttyS0 and ttyS1 are supported.
@@ -638,7 +683,7 @@ and is between 256 and 4096 characters. It is defined in the file
elanfreq= [X86-32]
See comment before function elanfreq_setup() in
- arch/i386/kernel/cpu/cpufreq/elanfreq.c.
+ arch/x86/kernel/cpu/cpufreq/elanfreq.c.
elevator= [IOSCHED]
Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
@@ -722,9 +767,6 @@ 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>
- hd?= [HW] (E)IDE subsystem
- hd?lun= See Documentation/ide/ide.txt.
-
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
@@ -737,8 +779,22 @@ and is between 256 and 4096 characters. It is defined in the file
hisax= [HW,ISDN]
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.
+ 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.
+ 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)
+ Note that 1GB pages can only be allocated at boot time
+ using hugepages= and not freed afterwards.
+ 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.
i8042.direct [HW] Put keyboard port into non-translated mode
i8042.dumbkbd [HW] Pretend that controller can only read data from
@@ -785,7 +841,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/ide/ide.txt.
idle= [X86]
- Format: idle=poll or idle=mwait
+ Format: idle=poll or idle=mwait, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly improves the performance
of waking up a idle CPU, but will use a lot of power and make the system
run hot. Not recommended.
@@ -793,6 +849,9 @@ and is between 256 and 4096 characters. It is defined in the file
to not use it because it doesn't save as much power as a normal idle
loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
as idle=poll.
+ idle=halt. Halt is forced to be used for CPU idle.
+ In such case C2/C3 won't be used again.
+ idle=nomwait. Disable mwait for CPU C-states
ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
Claim all unknown PCI IDE storage controllers.
@@ -961,6 +1020,10 @@ and is between 256 and 4096 characters. It is defined in the file
(only serial suported for now)
Format: <serial_device>[,baud]
+ kmac= [MIPS] korina ethernet MAC address.
+ Configure the RouterBoard 532 series on-chip
+ Ethernet adapter MAC address.
+
l2cr= [PPC]
l3cr= [PPC]
@@ -1015,6 +1078,9 @@ and is between 256 and 4096 characters. It is defined in the file
* [no]ncq: Turn on or off NCQ.
+ * nohrst, nosrst, norst: suppress hard, soft
+ and both resets.
+
If there are multiple matching configurations changing
the same attribute, the last one is used.
@@ -1166,7 +1232,30 @@ and is between 256 and 4096 characters. It is defined in the file
or
memmap=0x10000$0x18690000
- memtest= [KNL,X86_64] Enable memtest
+ 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.
+
+ memtest= [KNL,X86] Enable memtest
Format: <integer>
range: 0,4 : pattern number
default : 0 <disable>
@@ -1185,6 +1274,14 @@ and is between 256 and 4096 characters. It is defined in the file
mga= [HW,DRM]
+ 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.
+
mousedev.tap_time=
[MOUSE] Maximum time between finger touching and
leaving touchpad surface for touch to be considered
@@ -1208,6 +1305,11 @@ and is between 256 and 4096 characters. It is defined in the file
mtdparts= [MTD]
See drivers/mtd/cmdlinepart.c.
+ mtdset= [ARM]
+ ARM/S3C2412 JIVE boot control
+
+ See arch/arm/mach-s3c2412/mach-jive.c
+
mtouchusb.raw_coordinates=
[HW] Make the MicroTouch USB driver use raw coordinates
('y', default) or cooked coordinates ('n')
@@ -1234,6 +1336,13 @@ and is between 256 and 4096 characters. It is defined in the file
This usage is only documented in each driver source
file if at all.
+ nf_conntrack.acct=
+ [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.
+
nfsaddrs= [NFS]
See Documentation/filesystems/nfsroot.txt.
@@ -1343,6 +1452,12 @@ and is between 256 and 4096 characters. It is defined in the file
nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
+ nox2apic [X86-64,APIC] Do not enable x2APIC mode.
+
+ x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
+ default x2apic cluster mode on platforms
+ supporting x2apic.
+
noltlbs [PPC] Do not use large page/tlb entries for kernel
lowmem mapping on PPC40x.
@@ -1496,6 +1611,9 @@ and is between 256 and 4096 characters. It is defined in the file
Use with caution as certain devices share
address decoders between ROMs and other
resources.
+ norom [X86-32,X86_64] Do not assign address space to
+ expansion ROMs that do not already have
+ BIOS assigned address ranges.
irqmask=0xMMMM [X86-32] 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
@@ -1571,6 +1689,10 @@ and is between 256 and 4096 characters. It is defined in the file
Format: { parport<nr> | timid | 0 }
See also Documentation/parport.txt.
+ pmtmr= [X86] Manual setup of pmtmr I/O Port.
+ Override pmtimer IOPort with a hex value.
+ e.g. pmtmr=0x508
+
pnpacpi= [ACPI]
{ off }
@@ -1679,6 +1801,10 @@ and is between 256 and 4096 characters. It is defined in the file
Format: <reboot_mode>[,<reboot_mode2>[,...]]
See arch/*/kernel/reboot.c or arch/*/kernel/process.c
+ relax_domain_level=
+ [KNL, SMP] Set scheduler's default relax_domain_level.
+ See Documentation/cpusets.txt.
+
reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
reservetop= [X86-32]
@@ -1789,6 +1915,12 @@ and is between 256 and 4096 characters. It is defined in the file
shapers= [NET]
Maximal number of shapers.
+ 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.
+
sim710= [SCSI,HW]
See header of drivers/scsi/sim710.c.
@@ -1971,6 +2103,9 @@ and is between 256 and 4096 characters. It is defined in the file
snd-ymfpci= [HW,ALSA]
+ softlockup_panic=
+ [KNL] Should the soft-lockup detector generate panics.
+
sonypi.*= [HW] Sony Programmable I/O Control Device driver
See Documentation/sonypi.txt
@@ -2035,6 +2170,12 @@ and is between 256 and 4096 characters. It is defined in the file
tdfx= [HW,DRM]
+ 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.
+
thash_entries= [KNL,NET]
Set number of hash buckets for TCP connection
@@ -2062,13 +2203,6 @@ and is between 256 and 4096 characters. It is defined in the file
<deci-seconds>: poll all this frequency
0: no polling (default)
- tipar.timeout= [HW,PPT]
- Set communications timeout in tenths of a second
- (default 15).
-
- tipar.delay= [HW,PPT]
- Set inter-bit delay in microseconds (default 10).
-
tmscsim= [HW,SCSI]
See comment before function dc390_setup() in
drivers/scsi/tmscsim.c.
@@ -2102,6 +2236,10 @@ and is between 256 and 4096 characters. It is defined in the file
Note that genuine overcurrent events won't be
reported either.
+ unknown_nmi_panic
+ [X86-32,X86-64]
+ Set unknown_nmi_panic=1 early on boot.
+
usbcore.autosuspend=
[USB] The autosuspend time delay (in seconds) used
for newly-detected USB devices (default 2). This
@@ -2112,6 +2250,9 @@ and is between 256 and 4096 characters. It is defined in the file
usbhid.mousepoll=
[USBHID] The interval which mice are to be polled at.
+ add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in
+ kernel's map of available physical RAM.
+
vdso= [X86-32,SH,x86-64]
vdso=2: enable compat VDSO (default with COMPAT_VDSO)
vdso=1: enable VDSO (default)