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.txt92
1 files changed, 69 insertions, 23 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 6172e4360f60..e87bdbfbcc75 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
@@ -134,7 +140,7 @@ and is between 256 and 4096 characters. It is defined in the file
./include/asm/setup.h as COMMAND_LINE_SIZE.
- acpi= [HW,ACPI,X86-64,i386]
+ acpi= [HW,ACPI,X86]
Advanced Configuration and Power Interface
Format: { force | off | ht | strict | noirq | rsdt }
force -- enable ACPI if default was off
@@ -218,7 +224,7 @@ and is between 256 and 4096 characters. It is defined in the file
acpi_osi="!string2" # remove built-in string2
acpi_osi= # disable all strings
- acpi_pm_good [X86-32,X86-64]
+ acpi_pm_good [X86]
Override the pmtimer bug detection: force the kernel
to assume that this machine's pmtimer latches its value
and always returns good values.
@@ -231,6 +237,35 @@ 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 +285,9 @@ 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.
@@ -313,7 +351,7 @@ 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
@@ -459,7 +497,7 @@ and is between 256 and 4096 characters. It is defined in the file
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
+ code_bytes [X86] How many bytes of object code to print
in an oops report.
Range: 0 - 8192
Default: 64
@@ -592,7 +630,7 @@ and is between 256 and 4096 characters. It is defined in the file
MTRR settings. This parameter disables that behavior,
possibly causing your machine to run very slowly.
- disable_timer_pin_1 [i386,x86-64]
+ disable_timer_pin_1 [X86]
Disable PIN 1 of APIC timer
Can be useful to work around chipset bugs.
@@ -624,7 +662,7 @@ and is between 256 and 4096 characters. It is defined in the file
UART at the specified I/O port or MMIO address.
The options are the same as for ttyS, above.
- earlyprintk= [X86-32,X86-64,SH,BLACKFIN]
+ earlyprintk= [X86,SH,BLACKFIN]
earlyprintk=vga
earlyprintk=serial[,ttySn[,baudrate]]
earlyprintk=dbgp
@@ -659,7 +697,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/block/as-iosched.txt and
Documentation/block/deadline-iosched.txt for details.
- elfcorehdr= [IA64,PPC,SH,X86-32,X86_64]
+ elfcorehdr= [IA64,PPC,SH,X86]
Specifies physical address of start of kernel core
image elf header. Generally kexec loader will
pass this option to capture kernel.
@@ -670,7 +708,7 @@ 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).
@@ -743,7 +781,7 @@ 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
@@ -938,7 +976,7 @@ and is between 256 and 4096 characters. It is defined in the file
See comment before marvel_specify_io7 in
arch/alpha/kernel/core_marvel.c.
- io_delay= [X86-32,X86-64] I/O delay method
+ io_delay= [X86] I/O delay method
0x80
Standard port 0x80 based delay
0xed
@@ -1000,7 +1038,7 @@ and is between 256 and 4096 characters. It is defined in the file
keepinitrd [HW,ARM]
- kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
+ kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
specifies the amount of memory usable by the kernel
for non-movable allocations. The requested amount is
spread evenly throughout all nodes in the system. The
@@ -1034,7 +1072,7 @@ and is between 256 and 4096 characters. It is defined in the file
Configure the RouterBoard 532 series on-chip
Ethernet adapter MAC address.
- kstack=N [X86-32,X86-64] Print N words from the kernel stack
+ kstack=N [X86] Print N words from the kernel stack
in oops dumps.
l2cr= [PPC]
@@ -1044,7 +1082,7 @@ and is between 256 and 4096 characters. It is defined in the file
lapic [X86-32,APIC] Enable the local APIC even if BIOS
disabled it.
- lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer
+ lapic_timer_c2_ok [X86,APIC] trust the local apic timer
in C2 power state.
libata.dma= [LIBATA] DMA control
@@ -1229,7 +1267,7 @@ and is between 256 and 4096 characters. It is defined in the file
[KNL,SH] Allow user to override the default size for
per-device physically contiguous DMA buffers.
- memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact
+ memmap=exactmap [KNL,X86] Enable setting of an exact
E820 memory map, as specified by the user.
Such memmap=exactmap lines can be constructed based on
BIOS output or other requirements. See the memmap=nn@ss
@@ -1320,7 +1358,7 @@ and is between 256 and 4096 characters. It is defined in the file
mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
reporting absolute coordinates, such as tablets
- movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
+ movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
is similar to kernelcore except it specifies the
amount of memory used for migratable allocations.
If both kernelcore and movablecore is specified,
@@ -1422,7 +1460,7 @@ and is between 256 and 4096 characters. It is defined in the file
when a NMI is triggered.
Format: [state][,regs][,debounce][,die]
- nmi_watchdog= [KNL,BUGS=X86-32,X86-64] Debugging features for SMP kernels
+ nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
Format: [panic,][num]
Valid num: 0,1,2
0 - turn nmi_watchdog off
@@ -1475,11 +1513,11 @@ and is between 256 and 4096 characters. It is defined in the file
nodsp [SH] Disable hardware DSP at boot time.
- noefi [X86-32,X86-64] Disable EFI runtime services support.
+ noefi [X86] Disable EFI runtime services support.
noexec [IA-64]
- noexec [X86-32,X86-64]
+ noexec [X86]
On X86-32 available only on PAE configured kernels.
noexec=on: enable non-executable mappings (default)
noexec=off: disable non-executable mappings
@@ -1525,7 +1563,7 @@ and is between 256 and 4096 characters. It is defined in the file
noirqdebug [X86-32] Disables the code which attempts to detect and
disable unhandled interrupt sources.
- no_timer_check [X86-32,X86_64,APIC] Disables the code which tests for
+ no_timer_check [X86,APIC] Disables the code which tests for
broken timer IRQ sources.
noisapnp [ISAPNP] Disables ISA PnP code.
@@ -1588,6 +1626,8 @@ 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.
@@ -1689,7 +1729,7 @@ and is between 256 and 4096 characters. It is defined in the file
disable the use of PCIE advanced error reporting.
nodomains [PCI] Disable support for multiple PCI
root domains (aka PCI segments, in ACPI-speak).
- nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI
+ nommconf [X86] Disable use of MMCONFIG for PCI
Configuration
nomsi [MSI] If the PCI_MSI kernel config parameter is
enabled, this kernel boot option can be used to
@@ -1838,6 +1878,12 @@ 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
@@ -2380,7 +2426,7 @@ and is between 256 and 4096 characters. It is defined in the file
reported either.
unknown_nmi_panic
- [X86-32,X86-64]
+ [X86]
Set unknown_nmi_panic=1 early on boot.
usbcore.autosuspend=
@@ -2447,12 +2493,12 @@ 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
- vdso= [X86-32,SH,x86-64]
+ vdso= [X86,SH]
vdso=2: enable compat VDSO (default with COMPAT_VDSO)
vdso=1: enable VDSO (default)
vdso=0: disable VDSO mapping
- vdso32= [X86-32,X86-64]
+ vdso32= [X86]
vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
vdso32=1: enable 32-bit VDSO (default)
vdso32=0: disable 32-bit VDSO mapping
OpenPOWER on IntegriCloud