| Kernel Parameters |
| ~~~~~~~~~~~~~~~~~ |
| |
| The following is a consolidated list of the kernel parameters as implemented |
| (mostly) by the __setup() macro and sorted into English Dictionary order |
| (defined as ignoring all punctuation and sorting digits before letters in a |
| case insensitive manner), and with descriptions where known. |
| |
| Module parameters for loadable modules are specified only as the |
| parameter name with optional '=' and value as appropriate, such as: |
| |
| modprobe usbcore blinkenlights=1 |
| |
| Module parameters for modules that are built into the kernel image |
| are specified on the kernel command line with the module name plus |
| '.' plus parameter name, with '=' and value if appropriate, such as: |
| |
| usbcore.blinkenlights=1 |
| |
| This document may not be entirely up to date and comprehensive. The command |
| "modinfo -p ${modulename}" shows a current list of all parameters of a loadable |
| module. Loadable modules, after being loaded into the running kernel, also |
| reveal their parameters in /sys/module/${modulename}/parameters/. Some of these |
| parameters may be changed at runtime by the command |
| "echo -n ${value} > /sys/module/${modulename}/parameters/${parm}". |
| |
| The parameters listed below are only valid if certain kernel build options were |
| enabled and if respective hardware is present. The text in square brackets at |
| the beginning of each description states the restrictions within which a |
| parameter is applicable: |
| |
| ACPI ACPI support is enabled. |
| AGP AGP (Accelerated Graphics Port) is enabled. |
| ALSA ALSA sound support is enabled. |
| APIC APIC support is enabled. |
| APM Advanced Power Management support is enabled. |
| AVR32 AVR32 architecture is enabled. |
| AX25 Appropriate AX.25 support is enabled. |
| BLACKFIN Blackfin architecture is enabled. |
| DRM Direct Rendering Management support is enabled. |
| EDD BIOS Enhanced Disk Drive Services (EDD) is enabled |
| EFI EFI Partitioning (GPT) is enabled |
| EIDE EIDE/ATAPI support is enabled. |
| FB The frame buffer device is enabled. |
| HW Appropriate hardware is enabled. |
| IA-64 IA-64 architecture is enabled. |
| IOSCHED More than one I/O scheduler is enabled. |
| IP_PNP IP DHCP, BOOTP, or RARP is enabled. |
| ISAPNP ISA PnP code is enabled. |
| ISDN Appropriate ISDN support is enabled. |
| JOY Appropriate joystick support is enabled. |
| LIBATA Libata driver is enabled |
| LP Printer support is enabled. |
| LOOP Loopback device support is enabled. |
| M68k M68k architecture is enabled. |
| These options have more detailed description inside of |
| Documentation/m68k/kernel-options.txt. |
| MCA MCA bus support is enabled. |
| MDA MDA console support is enabled. |
| MOUSE Appropriate mouse support is enabled. |
| MSI Message Signaled Interrupts (PCI). |
| 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. |
| PARIDE The ParIDE (parallel port IDE) subsystem is enabled. |
| PARISC The PA-RISC architecture is enabled. |
| PCI PCI bus support is enabled. |
| PCIE PCI Express support is enabled. |
| PCMCIA The PCMCIA subsystem is enabled. |
| PNP Plug & Play support is enabled. |
| PPC PowerPC architecture is enabled. |
| PPT Parallel port support is enabled. |
| PS2 Appropriate PS/2 support is enabled. |
| RAM RAM disk support is enabled. |
| ROOTPLUG The example Root Plug LSM 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/. |
| SECURITY Different security models are enabled. |
| SELINUX SELinux support is enabled. |
| SERIAL Serial support is enabled. |
| SH SuperH architecture is enabled. |
| SMP The kernel is an SMP kernel. |
| SPARC Sparc architecture is enabled. |
| SWSUSP Software suspend is enabled. |
| TS Appropriate touchscreen support is enabled. |
| USB USB support is enabled. |
| USBHID USB Human Interface Device support is enabled. |
| V4L Video For Linux support is enabled. |
| VGA The VGA console has been enabled. |
| VT Virtual terminal support is enabled. |
| WDT Watchdog support is enabled. |
| XT IBM PC/XT MFM hard disk support is enabled. |
| X86-32 X86-32, aka i386 architecture is enabled. |
| X86-64 X86-64 architecture is enabled. |
| More X86-64 boot options can be found in |
| Documentation/x86_64/boot-options.txt . |
| |
| In addition, the following text indicates that the option: |
| |
| BUGS= Relates to possible processor bugs on the said processor. |
| KNL Is a kernel start-up parameter. |
| BOOT Is a boot loader parameter. |
| |
| Parameters denoted with BOOT are actually interpreted by the boot |
| loader, and have no meaning to the kernel directly. |
| Do not modify the syntax of boot loader parameters without extreme |
| need or coordination with <Documentation/i386/boot.txt>. |
| |
| There are also arch-specific kernel-parameters not documented here. |
| See for example <Documentation/x86_64/boot-options.txt>. |
| |
| Note that ALL kernel parameters listed below are CASE SENSITIVE, and that |
| a trailing = on the name of any parameter states that that parameter will |
| be entered as an environment variable, whereas its absence indicates that |
| it will appear as a kernel argument readable via /proc/cmdline by programs |
| running once the system is up. |
| |
| The number of kernel parameters is not limited, but the length of the |
| complete command line (parameters including spaces etc.) is limited to |
| a fixed number of characters. This limit depends on the architecture |
| 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] |
| Advanced Configuration and Power Interface |
| Format: { force | off | ht | strict | noirq } |
| 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. |
| |
| See also Documentation/power/pm.txt, pci=noacpi |
| |
| acpi_apic_instance= [ACPI, IOAPIC] |
| Format: <int> |
| 2: use 2nd APIC table, if available |
| 1,0: use 1st APIC table |
| default: 0 |
| |
| acpi_sleep= [HW,ACPI] Sleep options |
| Format: { s3_bios, s3_mode, s3_beep } |
| 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. |
| |
| acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode |
| Format: { level | edge | high | low } |
| |
| acpi_irq_balance [HW,ACPI] |
| ACPI will balance active IRQs |
| default in APIC mode |
| |
| acpi_irq_nobalance [HW,ACPI] |
| ACPI will not move active IRQs (default) |
| default in PIC mode |
| |
| acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for |
| use by PCI |
| Format: <irq>,<irq>... |
| |
| acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA |
| Format: <irq>,<irq>... |
| |
| acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT |
| |
| acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS |
| Format: To spoof as Windows 98: ="Microsoft Windows" |
| |
| acpi_osi= [HW,ACPI] Modify list of supported OS interface strings |
| acpi_osi="string1" # add string1 -- only one string |
| acpi_osi="!string2" # remove built-in string2 |
| acpi_osi= # disable all strings |
| |
| 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_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.debug_layer= [HW,ACPI] |
| Format: <int> |
| Each bit of the <int> indicates an ACPI debug layer, |
| 1: enable, 0: disable. It is useful for boot time |
| debugging. After system has booted up, it can be set |
| via /sys/module/acpi/parameters/debug_layer. |
| CONFIG_ACPI_DEBUG must be enabled for this to produce any output. |
| Available bits (add the numbers together) to enable debug output |
| for specific parts of the ACPI subsystem: |
| 0x01 utilities 0x02 hardware 0x04 events 0x08 tables |
| 0x10 namespace 0x20 parser 0x40 dispatcher |
| 0x80 executer 0x100 resources 0x200 acpica debugger |
| 0x400 os services 0x800 acpica disassembler. |
| The number can be in decimal or prefixed with 0x in hex. |
| Warning: Many of these options can produce a lot of |
| output and make your system unusable. Be very careful. |
| |
| acpi.debug_level= [HW,ACPI] |
| Format: <int> |
| Each bit of the <int> indicates an ACPI debug level, |
| 1: enable, 0: disable. It is useful for boot time |
| debugging. After system has booted up, it can be set |
| via /sys/module/acpi/parameters/debug_level. |
| CONFIG_ACPI_DEBUG must be enabled for this to produce any output. |
| Available bits (add the numbers together) to enable different |
| debug output levels of the ACPI subsystem: |
| 0x01 error 0x02 warn 0x04 init 0x08 debug object |
| 0x10 info 0x20 init names 0x40 parse 0x80 load |
| 0x100 dispatch 0x200 execute 0x400 names 0x800 operation region |
| 0x1000 bfield 0x2000 tables 0x4000 values 0x8000 objects |
| 0x10000 resources 0x20000 user requests 0x40000 package. |
| The number can be in decimal or prefixed with 0x in hex. |
| Warning: Many of these options can produce a lot of |
| output and make your system unusable. Be very careful. |
| |
| acpi_pm_good [X86-32,X86-64] |
| Override the pmtimer bug detection: force the kernel |
| to assume that this machine's pmtimer latches its value |
| and always returns good values. |
| |
| agp= [AGP] |
| { off | try_unsupported } |
| off: disable AGP support |
| try_unsupported: try to drive unsupported chipsets |
| (may crash computer or cause data corruption) |
| |
| enable_timer_pin_1 [i386,x86-64] |
| Enable PIN 1 of APIC timer |
| Can be useful to work around chipset bugs |
| (in particular on some ATI chipsets). |
| The kernel tries to set a reasonable default. |
| |
| disable_timer_pin_1 [i386,x86-64] |
| Disable PIN 1 of APIC timer |
| Can be useful to work around chipset bugs. |
| |
| ad1848= [HW,OSS] |
| Format: <io>,<irq>,<dma>,<dma2>,<type> |
| |
| 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. |
| |
| 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. |
| |
| amijoy.map= [HW,JOY] Amiga joystick support |
| Map of devices attached to JOY0DAT and JOY1DAT |
| Format: <a>,<b> |
| See also Documentation/kernel/input/joystick.txt |
| |
| analog.map= [HW,JOY] Analog joystick and gamepad support |
| Specifies type or capabilities of an analog joystick |
| connected to one of 16 gameports |
| Format: <type1>,<type2>,..<type16> |
| |
| apc= [HW,SPARC] |
| Power management functions (SPARCstation-4/5 + deriv.) |
| Format: noidle |
| Disable APC CPU standby support. SPARCstation-Fox does |
| 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 |
| Change the output verbosity whilst booting |
| Format: { quiet (default) | verbose | debug } |
| Change the amount of debugging information output |
| when initialising the APIC and IO-APIC components. |
| |
| apm= [APM] Advanced Power Management |
| See header of arch/i386/kernel/apm.c. |
| |
| arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards |
| Format: <io>,<irq>,<nodeID> |
| |
| ataflop= [HW,M68k] |
| |
| 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 |
| |
| atkbd.reset= [HW] Reset keyboard during initialization |
| |
| atkbd.set= [HW] Select keyboard code set |
| Format: <int> (2 = AT (default), 3 = PS/2) |
| |
| atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar |
| keyboards |
| |
| atkbd.softraw= [HW] Choose between synthetic and real raw mode |
| Format: <bool> (0 = real, 1 = synthetic (default)) |
| |
| atkbd.softrepeat= [HW] |
| Use software keyboard repeat |
| |
| autotest [IA64] |
| |
| baycom_epp= [HW,AX25] |
| Format: <io>,<mode> |
| |
| baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem |
| Format: <io>,<mode> |
| See header of drivers/net/hamradio/baycom_par.c. |
| |
| baycom_ser_fdx= [HW,AX25] |
| BayCom Serial Port AX.25 Modem (Full Duplex Mode) |
| Format: <io>,<irq>,<mode>[,<baud>] |
| See header of drivers/net/hamradio/baycom_ser_fdx.c. |
| |
| baycom_ser_hdx= [HW,AX25] |
| BayCom Serial Port AX.25 Modem (Half Duplex Mode) |
| Format: <io>,<irq>,<mode> |
| See header of drivers/net/hamradio/baycom_ser_hdx.c. |
| |
| boot_delay= Milliseconds to delay each printk during boot. |
| Values larger than 10 seconds (10000) are changed to |
| no delay (0). |
| Format: integer |
| |
| bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards) |
| bttv.radio= Most important insmod options are available as |
| kernel args too. |
| 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. |
| Sometimes CPU hardware bugs make them report the cache |
| size incorrectly. The kernel will attempt work arounds |
| to fix known problems, but for some CPUs it is not |
| possible to determine what the correct size should be. |
| This option provides an override for these situations. |
| |
| 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 |
| loaded. An invalid security module name will be treated |
| as if no module has been chosen. |
| |
| capability.disable= |
| [SECURITY] Disable capabilities. This would normally |
| be used only if an alternative security model is to be |
| configured. Potentially dangerous and should only be |
| used if you are entirely sure of the consequences. |
| |
| ccw_timeout_log [S390] |
| See Documentation/s390/CommonIO for details. |
| |
| cgroup_disable= [KNL] Disable a particular controller |
| Format: {name of the controller(s) to disable} |
| {Currently supported controllers - "memory"} |
| |
| checkreqprot [SELINUX] Set initial checkreqprot flag value. |
| Format: { "0" | "1" } |
| See security/selinux/Kconfig help text. |
| 0 -- check protection applied by kernel (includes |
| any implied execute protection). |
| 1 -- check protection requested by application. |
| Default value is set via a kernel config option. |
| Value can be changed at runtime via |
| /selinux/checkreqprot. |
| |
| cio_ignore= [S390] |
| See Documentation/s390/CommonIO for details. |
| |
| cio_msg= [S390] |
| See Documentation/s390/CommonIO for details. |
| |
| clock= [BUGS=X86-32, HW] gettimeofday clocksource override. |
| [Deprecated] |
| Forces specified clocksource (if available) to be used |
| when calculating gettimeofday(). If specified |
| clocksource is not available, it defaults to PIT. |
| Format: { pit | tsc | cyclone | pmtmr } |
| |
| clocksource= [GENERIC_TIME] Override the default clocksource |
| Format: <string> |
| Override the default clocksource and use the clocksource |
| with the name specified. |
| Some clocksource names to choose from, depending on |
| the platform: |
| [all] jiffies (this is the base, fallback clocksource) |
| [ACPI] acpi_pm |
| [ARM] imx_timer1,OSTS,netx_timer,mpu_timer2, |
| pxa_timer,timer3,32k_counter,timer0_1 |
| [AVR32] avr32 |
| [X86-32] pit,hpet,tsc,vmi-timer; |
| scx200_hrt on Geode; cyclone on IBM x440 |
| [MIPS] MIPS |
| [PARISC] cr16 |
| [S390] tod |
| [SH] SuperH |
| [SPARC64] tick |
| [X86-64] hpet,tsc |
| |
| clearcpuid=BITNUM [X86] |
| Disable CPUID feature X for the kernel. See |
| include/asm-x86/cpufeature.h for the valid bit numbers. |
| Note the Linux specific bits are not necessarily |
| stable over kernel options, but the vendor specific |
| ones should be. |
| Also note that user programs calling CPUID directly |
| or using the feature without checking anything |
| will still see it. This just prevents it from |
| being used by the kernel or shown in /proc/cpuinfo. |
| 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 |
| in an oops report. |
| 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 |
| force: allow force enabled of undocumented chips (ICH4, |
| VIA, nVidia) |
| |
| com20020= [HW,NET] ARCnet - COM20020 chipset |
| Format: |
| <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]] |
| |
| com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers) |
| Format: <io>[,<irq>] |
| |
| com90xx= [HW,NET] |
| ARCnet - COM90xx chipset (memory-mapped buffers) |
| Format: <io>[,<irq>[,<memstart>]] |
| |
| condev= [HW,S390] console device |
| conmode= |
| |
| console= [KNL] Output console device and options. |
| |
| tty<n> Use the virtual console device <n>. |
| |
| ttyS<n>[,options] |
| ttyUSB0[,options] |
| Use the specified serial port. The options are of |
| the form "bbbbpnf", where "bbbb" is the baud rate, |
| "p" is parity ("n", "o", or "e"), "n" is number of |
| bits, and "f" is flow control ("r" for RTS or |
| omit it). Default is "9600n8". |
| |
| See Documentation/serial-console.txt for more |
| information. See |
| Documentation/networking/netconsole.txt for an |
| alternative. |
| |
| uart[8250],io,<addr>[,options] |
| uart[8250],mmio,<addr>[,options] |
| Start an early, polled-mode console on the 8250/16550 |
| UART at the specified I/O port or MMIO address, |
| switching to the matching ttyS device later. The |
| options are the same as for ttyS, above. |
| |
| earlycon= [KNL] Output early console device and options. |
| uart[8250],io,<addr>[,options] |
| uart[8250],mmio,<addr>[,options] |
| Start an early, polled-mode console on the 8250/16550 |
| UART at the specified I/O port or MMIO address. |
| The options are the same as for ttyS, above. |
| |
| no_console_suspend |
| [HW] Never suspend the console |
| Disable suspending of consoles during suspend and |
| hibernate operations. Once disabled, debugging |
| messages can reach various consoles while the rest |
| of the system is being put to sleep (ie, while |
| debugging driver suspend/resume hooks). This may |
| not work reliably with all consoles, but is known |
| to work with serial and VGA consoles. |
| |
| cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver |
| Format: |
| <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] |
| |
| crashkernel=nn[KMG]@ss[KMG] |
| [KNL] Reserve a chunk of physical memory to |
| hold a kernel to switch to with kexec on panic. |
| |
| crashkernel=range1:size1[,range2:size2,...][@offset] |
| [KNL] Same as above, but depends on the memory |
| in the running system. The syntax of range is |
| start-[end] where start and end are both |
| a memory unit (amount[KMG]). See also |
| Documentation/kdump/kdump.txt for a example. |
| |
| cs4232= [HW,OSS] |
| Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq> |
| |
| cs89x0_dma= [HW,NET] |
| Format: <dma> |
| |
| cs89x0_media= [HW,NET] |
| Format: { rj45 | aui | bnc } |
| |
| dasd= [HW,NET] |
| See header of drivers/s390/block/dasd_devmap.c. |
| |
| db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port |
| (one device per port) |
| Format: <port#>,<type> |
| See also Documentation/input/joystick-parport.txt |
| |
| debug [KNL] Enable kernel debugging (events log level). |
| |
| debug_locks_verbose= |
| [KNL] verbose self-tests |
| Format=<0|1> |
| Print debugging info while doing the locking API |
| self-tests. |
| We default to 0 (no extra messages), setting it to |
| 1 will print _a lot_ more information - normally |
| only useful to kernel developers. |
| |
| decnet.addr= [HW,NET] |
| Format: <area>[,<node>] |
| See also Documentation/networking/decnet.txt. |
| |
| vt.default_blu= [VT] |
| Format: <blue0>,<blue1>,<blue2>,...,<blue15> |
| Change the default blue palette of the console. |
| This is a 16-member array composed of values |
| ranging from 0-255. |
| |
| vt.default_grn= [VT] |
| Format: <green0>,<green1>,<green2>,...,<green15> |
| Change the default green palette of the console. |
| This is a 16-member array composed of values |
| ranging from 0-255. |
| |
| vt.default_red= [VT] |
| Format: <red0>,<red1>,<red2>,...,<red15> |
| Change the default red palette of the console. |
| This is a 16-member array composed of values |
| ranging from 0-255. |
| |
| vt.default_utf8= |
| [VT] |
| Format=<0|1> |
| Set system-wide default UTF-8 mode for all tty's. |
| Default is 1, i.e. UTF-8 mode is enabled for all |
| newly opened terminals. |
| |
| dhash_entries= [KNL] |
| Set number of hash buckets for dentry cache. |
| |
| digi= [HW,SERIAL] |
| IO parameters + enable/disable command. |
| |
| digiepca= [HW,SERIAL] |
| See drivers/char/README.epca and |
| Documentation/digiepca.txt. |
| |
| 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 |
| MTRR settings. This parameter disables that behavior, |
| possibly causing your machine to run very slowly. |
| |
| dmasound= [HW,OSS] Sound subsystem buffers |
| |
| dscc4.setup= [NET] |
| |
| dtc3181e= [HW,SCSI] |
| |
| earlyprintk= [X86-32,X86-64,SH,BLACKFIN] |
| earlyprintk=vga |
| earlyprintk=serial[,ttySn[,baudrate]] |
| |
| Append ",keep" to not disable it when the real console |
| takes over. |
| |
| Only vga or serial at a time, not both. |
| |
| Currently only ttyS0 and ttyS1 are supported. |
| |
| Interaction with the standard serial driver is not |
| very good. |
| |
| The VGA output is eventually overwritten by the real |
| console. |
| |
| eata= [HW,SCSI] |
| |
| edd= [EDD] |
| Format: {"off" | "on" | "skip[mbr]"} |
| |
| eisa_irq_edge= [PARISC,HW] |
| See header of drivers/parisc/eisa.c. |
| |
| elanfreq= [X86-32] |
| See comment before function elanfreq_setup() in |
| arch/i386/kernel/cpu/cpufreq/elanfreq.c. |
| |
| elevator= [IOSCHED] |
| Format: {"anticipatory" | "cfq" | "deadline" | "noop"} |
| See Documentation/block/as-iosched.txt and |
| Documentation/block/deadline-iosched.txt for details. |
| |
| elfcorehdr= [X86-32, X86_64] |
| Specifies physical address of start of kernel core |
| image elf header. Generally kexec loader will |
| pass this option to capture kernel. |
| See Documentation/kdump/kdump.txt for details. |
| |
| enforcing [SELINUX] Set initial enforcing status. |
| Format: {"0" | "1"} |
| See security/selinux/Kconfig help text. |
| 0 -- permissive (log only, no denials). |
| 1 -- enforcing (deny and log). |
| Default value is 0. |
| Value can be changed at runtime via /selinux/enforce. |
| |
| es1371= [HW,OSS] |
| Format: <spdif>,[<nomix>,[<amplifier>]] |
| See also header of sound/oss/es1371.c. |
| |
| 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] |
| General fault injection mechanism. |
| 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/floppy.txt. |
| |
| gamecon.map[2|3]= |
| [HW,JOY] Multisystem joystick and NES/SNES/PSX pad |
| support via parallel port (up to 5 devices per port) |
| Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5> |
| See also Documentation/input/joystick-parport.txt |
| |
| gamma= [HW,DRM] |
| |
| gart_fix_e820= [X86_64] disable the fix e820 for K8 GART |
| Format: off | on |
| default: on |
| |
| 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 IA-64, off otherwise. |
| Format: 0 | 1 (for off | on) |
| |
| hcl= [IA-64] SGI's Hardware Graph compatibility layer |
| |
| 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 |
| size on bigger boxes. |
| |
| highres= [KNL] Enable/disable high resolution timer mode. |
| Valid parameters: "on", "off" |
| Default: "on" |
| |
| 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. |
| |
| i8042.direct [HW] Put keyboard port into non-translated mode |
| i8042.dumbkbd [HW] Pretend that controller can only read data from |
| keyboard and cannot control its state |
| (Don't attempt to blink the leds) |
| i8042.noaux [HW] Don't check for auxiliary (== mouse) port |
| i8042.nokbd [HW] Don't check/create keyboard port |
| i8042.noloop [HW] Disable the AUX Loopback command while probing |
| for the AUX port |
| i8042.nomux [HW] Don't check presence of an active multiplexing |
| 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 |
| |
| i810= [HW,DRM] |
| |
| i8k.ignore_dmi [HW] Continue probing hardware even if DMI data |
| indicates that the driver is running on unsupported |
| hardware. |
| i8k.force [HW] Activate i8k driver even if SMM BIOS signature |
| does not match list of supported models. |
| i8k.power_status |
| [HW] Report power status in /proc/i8k |
| (disabled by default) |
| 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>]]] |
| |
| ide= [HW] (E)IDE subsystem |
| Format: ide=nodma or ide=doubler |
| See Documentation/ide/ide.txt. |
| |
| idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed |
| See Documentation/ide/ide.txt. |
| |
| idle= [X86] |
| Format: idle=poll or idle=mwait |
| 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. |
| idle=mwait. On systems which support MONITOR/MWAIT but the kernel chose |
| 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. |
| |
| ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem |
| Claim all unknown PCI IDE storage controllers. |
| |
| ignore_loglevel [KNL] |
| Ignore loglevel setting - this will print /all/ |
| kernel messages to the console. Useful for debugging. |
| |
| ihash_entries= [KNL] |
| Set number of hash buckets for inode cache. |
| |
| in2000= [HW,SCSI] |
| See header of drivers/scsi/in2000.c. |
| |
| init= [KNL] |
| Format: <full_path> |
| Run specified binary instead of /sbin/init as init |
| process. |
| |
| initcall_debug [KNL] Trace initcalls as they are executed. Useful |
| for working out where the kernel is dying during |
| startup. |
| |
| initrd= [BOOT] Specify the location of the initial ramdisk |
| |
| inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver |
| Format: <irq> |
| |
| inttest= [IA64] |
| |
| iommu= [x86] |
| off |
| force |
| noforce |
| biomerge |
| panic |
| nopanic |
| merge |
| nomerge |
| forcesac |
| soft |
| |
| |
| intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option |
| off |
| Disable intel iommu driver. |
| igfx_off [Default Off] |
| By default, gfx is mapped as normal device. If a gfx |
| device has a dedicated DMAR unit, the DMAR unit is |
| bypassed by not enabling DMAR with this option. In |
| this case, gfx device will use physical address for |
| DMA. |
| forcedac [x86_64] |
| With this option iommu will not optimize to look |
| for io virtual address below 32 bit forcing dual |
| address cycle on pci bus for cards supporting greater |
| than 32 bit addressing. The default is to look |
| for translation below 32 bit and if not available |
| then look in the higher range. |
| strict [Default Off] |
| With this option on every unmap_single operation will |
| result in a hardware IOTLB flush operation as opposed |
| to batching them for performance. |
| |
| io_delay= [X86-32,X86-64] I/O delay method |
| 0x80 |
| Standard port 0x80 based delay |
| 0xed |
| Alternate port 0xed based delay (needed on some systems) |
| udelay |
| Simple two microseconds delay |
| none |
| No delay |
| |
| io7= [HW] IO7 for Marvel based alpha systems |
| See comment before marvel_specify_io7 in |
| arch/alpha/kernel/core_marvel.c. |
| |
| ip= [IP_PNP] |
| See Documentation/filesystems/nfsroot.txt. |
| |
| ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards |
| 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. |
| |
| 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>.... |
| |
| irqfixup [HW] |
| When an interrupt is not handled search all handlers |
| for it. Intended to get systems with badly broken |
| firmware running. |
| |
| irqpoll [HW] |
| When an interrupt is not handled search all handlers |
| for it. Also check all handlers each timer |
| interrupt. Intended to get systems with badly broken |
| firmware running. |
| |
| isapnp= [ISAPNP] |
| Format: <RDP>,<reset>,<pci_scan>,<verbosity> |
| |
| isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler. |
| Format: |
| <cpu number>,...,<cpu number> |
| or |
| <cpu number>-<cpu number> (must be a positive range in ascending order) |
| or a mixture |
| <cpu number>,...,<cpu number>-<cpu number> |
| This option can be used to specify one or more CPUs |
| to isolate from the general SMP balancing and scheduling |
| algorithms. The only way to move a process onto or off |
| an "isolated" CPU is via the CPU affinity syscalls. |
| <cpu number> begins at 0 and the maximum value is |
| "number of CPUs in system - 1". |
| |
| This option is the preferred way to isolate CPUs. The |
| alternative -- manually setting the CPU mask of all |
| tasks in the system -- can cause problems and |
| suboptimal load balancer performance. |
| |
| iucv= [HW,NET] |
| |
| js= [HW,JOY] Analog joystick |
| See Documentation/input/joystick.txt. |
| |
| kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] 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 |
| remaining memory in each node is used for Movable |
| pages. In the event, a node is too small to have both |
| kernelcore and Movable pages, kernelcore pages will |
| take priority and other nodes will have a larger number |
| of kernelcore pages. The Movable zone is used for the |
| allocation of pages that may be reclaimed or moved |
| by the page migration subsystem. This means that |
| HugeTLB pages may not be allocated from this zone. |
| Note that allocations like PTEs-from-HighMem still |
| use the HighMem zone if it exists, and the Normal |
| zone if it does not. |
| |
| movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter |
| is similar to kernelcore except it specifies the |
| amount of memory used for migratable allocations. |
| If both kernelcore and movablecore is specified, |
| then kernelcore will be at *least* the specified |
| value but may be more. If movablecore on its own |
| is specified, the administrator must be careful |
| that the amount of memory usable for all allocations |
| is not too small. |
| |
| keepinitrd [HW,ARM] |
| |
| kstack=N [X86-32,X86-64] Print N words from the kernel stack |
| in oops dumps. |
| |
| kgdboc= [HW] kgdb over consoles. |
| Requires a tty driver that supports console polling. |
| (only serial suported for now) |
| Format: <serial_device>[,baud] |
| |
| l2cr= [PPC] |
| |
| l3cr= [PPC] |
| |
| 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 in |
| C2 power state. |
| |
| libata.dma= [LIBATA] DMA control |
| libata.dma=0 Disable all PATA and SATA DMA |
| libata.dma=1 PATA and SATA Disk DMA only |
| libata.dma=2 ATAPI (CDROM) DMA only |
| libata.dma=4 Compact Flash DMA only |
| Combinations also work, so libata.dma=3 enables DMA |
| for disks and CDROMs, but not CFs. |
| |
| libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume |
| when set. |
| Format: <int> |
| |
| 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 |
| 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 |
| values are used. If ID hasn't been specified yet, the |
| configuration applies to all ports, links and devices. |
| |
| If only DEVICE is omitted, the parameter applies to |
| the port and all links and devices behind it. DEVICE |
| number of 0 either selects the first device or the |
| first fan-out link behind PMP device. It does not |
| select the host link. DEVICE number of 15 selects the |
| host link and device attached to it. |
| |
| The VAL specifies the configuration to force. As long |
| as there's no ambiguity shortcut notation is allowed. |
| For example, both 1.5 and 1.5G would work for 1.5Gbps. |
| The following configurations can be forced. |
| |
| * Cable type: 40c, 80c, short40c, unk, ign or sata. |
| Any ID with matching PORT is used. |
| |
| * SATA link speed limit: 1.5Gbps or 3.0Gbps. |
| |
| * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7]. |
| udma[/][16,25,33,44,66,100,133] notation is also |
| allowed. |
| |
| * [no]ncq: Turn on or off NCQ. |
| |
| If there are multiple matching configurations changing |
| the same attribute, the last one is used. |
| |
| load_ramdisk= [RAM] List of ramdisks to load from floppy |
| See Documentation/ramdisk.txt. |
| |
| lockd.nlm_grace_period=P [NFS] Assign grace period. |
| Format: <integer> |
| |
| lockd.nlm_tcpport=N [NFS] Assign TCP port. |
| Format: <integer> |
| |
| lockd.nlm_timeout=T [NFS] Assign timeout value. |
| Format: <integer> |
| |
| lockd.nlm_udpport=M [NFS] Assign UDP port. |
| Format: <integer> |
| |
| logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver |
| Format: <irq> |
| |
| loglevel= All Kernel Messages with a loglevel smaller than the |
| console loglevel will be printed to the console. It can |
| also be changed with klogd or other programs. The |
| loglevels are defined as follows: |
| |
| 0 (KERN_EMERG) system is unusable |
| 1 (KERN_ALERT) action must be taken immediately |
| 2 (KERN_CRIT) critical conditions |
| 3 (KERN_ERR) error conditions |
| 4 (KERN_WARNING) warning conditions |
| 5 (KERN_NOTICE) normal but significant condition |
| 6 (KERN_INFO) informational |
| 7 (KERN_DEBUG) debug-level messages |
| |
| log_buf_len=n Sets the size of the printk ring buffer, in bytes. |
| Format: { n | nk | nM } |
| n must be a power of two. The default size |
| is set in the kernel config file. |
| |
| logo.nologo [FB] Disables display of the built-in Linux logo. |
| This may be used to provide more screen space for |
| kernel log messages and is useful when debugging |
| kernel boot problems. |
| |
| lp=0 [LP] Specify parallel ports to use, e.g, |
| lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses |
| lp=reset first parallel port). 'lp=0' disables the |
| lp=auto printer driver. 'lp=reset' (which can be |
| specified in addition to the ports) causes |
| attached printers to be reset. Using |
| lp=port1,port2,... specifies the parallel ports |
| to associate lp devices with, starting with |
| lp0. A port specification may be 'none' to skip |
| that lp device, or a parport name such as |
| 'parport0'. Specifying 'lp=auto' instead of a |
| port specification list means that device IDs |
| from each port should be examined, to see if |
| an IEEE 1284-compliant printer is attached; if |
| so, the driver will manage that printer. |
| See also header of drivers/char/lp.c. |
| |
| lpj=n [KNL] |
| Sets loops_per_jiffy to given constant, thus avoiding |
| time-consuming boot-time autodetection (up to 250 ms per |
| CPU). 0 enables autodetection (default). To determine |
| the correct value for your kernel, boot with normal |
| autodetection and see what value is printed. Note that |
| on SMP systems the preset will be applied to all CPUs, |
| which is likely to cause problems if your CPUs need |
| significantly divergent settings. An incorrect value |
| will cause delays in the kernel to be wrong, leading to |
| unpredictable I/O errors and other breakage. Although |
| unlikely, in the extreme case this might damage your |
| hardware. |
| |
| ltpc= [NET] |
| Format: <io>,<irq>,<dma> |
| |
| mac5380= [HW,SCSI] Format: |
| <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags> |
| |
| mac53c9x= [HW,SCSI] Format: |
| <num_esps>,<disconnect>,<nosync>,<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 |
| |
| max_loop= [LOOP] Maximum number of loopback devices that can |
| be mounted |
| Format: <1-256> |
| |
| maxcpus= [SMP] Maximum number of processors that an SMP kernel |
| should make use of. maxcpus=n : n >= 0 limits the |
| kernel to using 'n' processors. n=0 is a special case, |
| it is equivalent to "nosmp", which also disables |
| the IO APIC. |
| |
| max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or |
| equal to this physical address is ignored. |
| |
| 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 |
| |
| mce=option [X86-64] See Documentation/x86_64/boot-options.txt |
| |
| md= [HW] RAID subsystems devices and level |
| See Documentation/md.txt. |
| |
| mdacon= [MDA] |
| Format: <first>,<last> |
| Specifies range of consoles to be captured by the MDA. |
| |
| mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory |
| Amount of memory to be used when the kernel is not able |
| to see the whole system memory or for test. |
| [X86-32] Use together with memmap= to avoid physical |
| address space collisions. Without memmap= PCI devices |
| could be placed at addresses belonging to unused RAM. |
| |
| mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel |
| memory. |
| |
| memmap=exactmap [KNL,X86-32,X86_64] 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 |
| option description. |
| |
| memmap=nn[KMG]@ss[KMG] |
| [KNL] Force usage of a specific region of memory |
| Region of memory to be used, from ss to ss+nn. |
| |
| memmap=nn[KMG]#ss[KMG] |
| [KNL,ACPI] Mark specific memory as ACPI data. |
| Region of memory to be used, from ss to ss+nn. |
| |
| memmap=nn[KMG]$ss[KMG] |
| [KNL,ACPI] Mark specific memory as reserved. |
| Region of memory to be used, from ss to ss+nn. |
| Example: Exclude memory from 0x18690000-0x1869ffff |
| memmap=64K$0x18690000 |
| or |
| memmap=0x10000$0x18690000 |
| |
| memtest= [KNL,X86_64] Enable memtest |
| Format: <integer> |
| range: 0,4 : pattern number |
| default : 0 <disable> |
| |
| meye.*= [HW] Set MotionEye Camera parameters |
| See Documentation/video4linux/meye.txt. |
| |
| mfgpt_irq= [IA-32] Specify the IRQ to use for the |
| Multi-Function General Purpose Timers on AMD Geode |
| platforms. |
| |
| mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when |
| the BIOS has incorrectly applied a workaround. TinyBIOS |
| version 0.98 is known to be affected, 0.99 fixes the |
| problem by letting the user disable the workaround. |
| |
| mga= [HW,DRM] |
| |
| mousedev.tap_time= |
| [MOUSE] Maximum time between finger touching and |
| leaving touchpad surface for touch to be considered |
| a tap and be reported as a left button click (for |
| touchpads working in absolute mode only). |
| Format: <msecs> |
| mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices |
| reporting absolute coordinates, such as tablets |
| mousedev.yres= [MOUSE] Vertical screen resolution, used for devices |
| reporting absolute coordinates, such as tablets |
| |
| mpu401= [HW,OSS] |
| Format: <io>,<irq> |
| |
| MTD_Partition= [MTD] |
| Format: <name>,<region-number>,<size>,<offset> |
| |
| MTD_Region= [MTD] Format: |
| <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>] |
| |
| mtdparts= [MTD] |
| See drivers/mtd/cmdlinepart.c. |
| |
| mtouchusb.raw_coordinates= |
| [HW] Make the MicroTouch USB driver use raw coordinates |
| ('y', default) or cooked coordinates ('n') |
| |
| 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 |
| something different and driver-specific. |
| This usage is only documented in each driver source |
| file if at all. |
| |
| nfsaddrs= [NFS] |
| See Documentation/filesystems/nfsroot.txt. |
| |
| nfsroot= [NFS] nfs root filesystem for disk-less boxes. |
| See Documentation/filesystems/nfsroot.txt. |
| |
| nfs.callback_tcpport= |
| [NFS] set the TCP port on which the NFSv4 callback |
| channel should listen. |
| |
| nfs.idmap_cache_timeout= |
| [NFS] set the maximum lifetime for idmapper cache |
| entries. |
| |
| nfs.enable_ino64= |
| [NFS] enable 64-bit inode numbers. |
| If zero, the NFS client will fake up a 32-bit inode |
| number for the readdir() and stat() syscalls instead |
| of returning the full 64-bit number. |
| The default is to return 64-bit inode numbers. |
| |
| nmi_debug= [KNL,AVR32] Specify one or more actions to take |
| when a NMI is triggered. |
| Format: [state][,regs][,debounce][,die] |
| |
| nmi_watchdog= [KNL,BUGS=X86-32] Debugging features for SMP kernels |
| |
| no387 [BUGS=X86-32] Tells the kernel to use the 387 maths |
| emulation library even if a 387 maths coprocessor |
| is present. |
| |
| noaliencache [MM, NUMA, SLAB] Disables the allocation of alien |
| caches in the slab allocator. Saves per-node memory, |
| but will impact performance. |
| |
| noalign [KNL,ARM] |
| |
| noapic [SMP,APIC] Tells the kernel to not make use of any |
| IOAPICs that may be present in the system. |
| |
| nobats [PPC] Do not use BATs for mapping kernel lowmem |
| on "Classic" PPC cores. |
| |
| nocache [ARM] |
| |
| nodelayacct [KNL] Disable per-task delay accounting |
| |
| nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects. |
| |
| noefi [X86-32,X86-64] Disable EFI runtime services support. |
| |
| noexec [IA-64] |
| |
| noexec [X86-32,X86-64] |
| On X86-32 available only on PAE configured kernels. |
| noexec=on: enable non-executable mappings (default) |
| noexec=off: disable non-executable mappings |
| |
| noexec32 [X86-64] |
| This affects only 32-bit executables. |
| noexec32=on: enable non-executable mappings (default) |
| read doesn't imply executable mappings |
| noexec32=off: disable non-executable mappings |
| read implies executable mappings |
| |
| nofxsr [BUGS=X86-32] Disables x86 floating point extended |
| register save and restore. The kernel will only save |
| legacy floating-point registers on task switch. |
| |
| noclflush [BUGS=X86] Don't use the CLFLUSH instruction |
| |
| nohlt [BUGS=ARM] |
| |
| no-hlt [BUGS=X86-32] Tells the kernel that the hlt |
| instruction doesn't work correctly and not to |
| use it. |
| |
| nohalt [IA-64] Tells the kernel not to use the power saving |
| function PAL_HALT_LIGHT when idle. This increases |
| power-consumption. On the positive side, it reduces |
| interrupt wake-up latency, which may improve performance |
| in certain environments such as networked servers or |
| real-time systems. |
| |
| nohz= [KNL] Boottime enable/disable dynamic ticks |
| Valid arguments: on, off |
| Default: on |
| |
| noirqbalance [X86-32,SMP,KNL] Disable kernel irq balancing |
| |
| 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 |
| broken timer IRQ sources. |
| |
| noisapnp [ISAPNP] Disables ISA PnP code. |
| |
| noinitrd [RAM] Tells the kernel not to load any configured |
| initial RAM disk. |
| |
| nointroute [IA-64] |
| |
| nojitter [IA64] Disables jitter checking for ITC timers. |
| |
| nolapic [X86-32,APIC] Do not enable or use the local APIC. |
| |
| nolapic_timer [X86-32,APIC] Do not use the local APIC timer. |
| |
| noltlbs [PPC] Do not use large page/tlb entries for kernel |
| lowmem mapping on PPC40x. |
| |
| nomca [IA-64] Disable machine check abort handling |
| |
| nomce [X86-32] Machine Check Exception |
| |
| nomfgpt [X86-32] Disable Multi-Function General Purpose |
| Timer usage (for AMD Geode machines). |
| |
| noreplace-paravirt [X86-32,PV_OPS] Don't patch paravirt_ops |
| |
| noreplace-smp [X86-32,SMP] Don't replace SMP instructions |
| with UP alternatives |
| |
| noresidual [PPC] Don't use residual data on PReP machines. |
| |
| noresume [SWSUSP] Disables resume and restores original swap |
| space. |
| |
| no-scroll [VGA] Disables scrollback. |
| This is required for the Braillex ib80-piezo Braille |
| reader made by F.H. Papenmeier (Germany). |
| |
| nosbagart [IA-64] |
| |
| nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support. |
| |
| nosmp [SMP] Tells an SMP kernel to act as a UP kernel, |
| and disable the IO APIC. legacy for "maxcpus=0". |
| |
| nosoftlockup [KNL] Disable the soft-lockup detector. |
| |
| nosync [HW,M68K] Disables sync negotiation for all devices. |
| |
| notsc [BUGS=X86-32] Disable Time Stamp Counter |
| |
| nousb [USB] Disable the USB subsystem |
| |
| nowb [ARM] |
| |
| nptcg= [IA64] Override max number of concurrent global TLB |
| purges which is reported from either PAL_VM_SUMMARY or |
| SAL PALO. |
| |
| numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA. |
| one of ['zone', 'node', 'default'] can be specified |
| This can be set from sysctl after boot. |
| See Documentation/sysctl/vm.txt for details. |
| |
| nr_uarts= [SERIAL] maximum number of UARTs to be registered. |
| |
| olpc_ec_timeout= [OLPC] ms delay when issuing EC commands |
| Rather than timing out after 20 ms if an EC |
| command is not properly ACKed, override the length |
| of the timeout. We have interrupts disabled while |
| waiting for the ACK, so if this is set too high |
| interrupts *may* be lost! |
| |
| opl3= [HW,OSS] |
| Format: <io> |
| |
| oprofile.timer= [HW] |
| Use timer interrupt instead of performance counters |
| |
| osst= [HW,SCSI] SCSI Tape Driver |
| Format: <buffer_size>,<write_threshold> |
| See also Documentation/scsi/st.txt. |
| |
| panic= [KNL] Kernel behaviour on panic |
| Format: <timeout> |
| |
| parkbd.port= [HW] Parallel port number the keyboard adapter is |
| connected to, default is 0. |
| Format: <parport#> |
| parkbd.mode= [HW] Parallel port keyboard adapter mode of operation, |
| 0 for XT, 1 for AT (default is AT). |
| Format: <mode> |
| |
| parport= [HW,PPT] Specify parallel ports. 0 disables. |
| Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] } |
| Use 'auto' to force the driver to use any |
| IRQ/DMA settings detected (the default is to |
| ignore detected IRQ/DMA settings because of |
| possible conflicts). You can specify the base |
| address, IRQ, and DMA settings; IRQ and DMA |
| should be numbers, or 'auto' (for using detected |
| settings on that particular port), or 'nofifo' |
| (to avoid using a FIFO even if it is detected). |
| Parallel ports are assigned in the order they |
| are specified on the command line, starting |
| with parport0. |
| |
| parport_init_mode= [HW,PPT] |
| Configure VIA parallel port to operate in |
| a specific mode. This is necessary on Pegasos |
| computer where firmware has no options for setting |
| up parallel port mode and sets it to spp. |
| 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 |
| your oopses keep scrolling off the screen. |
| |
| pcbit= [HW,ISDN] |
| |
| pcd. [PARIDE] |
| See header of drivers/block/paride/pcd.c. |
| See also Documentation/paride.txt. |
| |
| pci=option[,option...] [PCI] various PCI subsystem options: |
| off [X86-32] don't probe for the PCI bus |
| bios [X86-32] force use of PCI BIOS, don't access |
| the hardware directly. Use this if your machine |
| has a non-standard PCI host bridge. |
| nobios [X86-32] disallow use of PCI BIOS, only direct |
| hardware access methods are allowed. Use this |
| if you experience crashes upon bootup and you |
| suspect they are caused by the BIOS. |
| conf1 [X86-32] Force use of PCI Configuration |
| Mechanism 1. |
| conf2 [X86-32] Force use of PCI Configuration |
| Mechanism 2. |
| noaer [PCIE] If the PCIEAER kernel config parameter is |
| enabled, this kernel boot option can be used to |
| 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 |
| Configuration |
| nomsi [MSI] If the PCI_MSI kernel config parameter is |
| enabled, this kernel boot option can be used to |
| disable the use of MSI interrupts system-wide. |
| biosirq [X86-32] Use PCI BIOS calls to get the interrupt |
| routing table. These calls are known to be buggy |
| on several machines and they hang the machine |
| when used, but on other computers it's the only |
| way to get the interrupt routing table. Try |
| this option if the kernel is unable to allocate |
| IRQs or discover secondary PCI buses on your |
| motherboard. |
| rom [X86-32] Assign address space to expansion ROMs. |
| Use with caution as certain devices share |
| address decoders between ROMs and other |
| resources. |
| 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 |
| this way. |
| pirqaddr=0xAAAAA [X86-32] Specify the physical address |
| of the PIRQ table (normally generated |
| by the BIOS) if it is outside the |
| F0000h-100000h range. |
| lastbus=N [X86-32] Scan all buses thru bus #N. Can be |
| useful if the kernel is unable to find your |
| secondary buses and you want to tell it |
| explicitly which ones they are. |
| assign-busses [X86-32] Always assign all PCI bus |
| numbers ourselves, overriding |
| whatever the firmware may have done. |
| usepirqmask [X86-32] Honor the possible IRQ mask stored |
| in the BIOS $PIR table. This is needed on |
| some systems with broken BIOSes, notably |
| some HP Pavilion N5400 and Omnibook XE3 |
| notebooks. This will have no effect if ACPI |
| IRQ routing is enabled. |
| noacpi [X86-32] Do not use ACPI for IRQ routing |
| or for PCI scanning. |
| use_crs [X86-32] Use _CRS for PCI resource |
| allocation. |
| routeirq Do IRQ routing for all PCI devices. |
| This is normally done in pci_enable_device(), |
| so this option is a temporary workaround |
| for broken drivers that don't call it. |
| firmware [ARM] Do not re-enumerate the bus but instead |
| just use the configuration from the |
| bootloader. This is currently used on |
| IXP2000 systems where the bus has to be |
| configured a certain way for adjunct CPUs. |
| noearly [X86] Don't do any early type 1 scanning. |
| This might help on some broken boards which |
| machine check when some devices' config space |
| is read. But various workarounds are disabled |
| and some IOMMU drivers will not work. |
| bfsort Sort PCI devices into breadth-first order. |
| This sorting is done to get a device |
| order compatible with older (<= 2.4) kernels. |
| nobfsort Don't sort PCI devices into breadth-first order. |
| cbiosize=nn[KMG] The fixed amount of bus space which is |
| reserved for the CardBus bridge's IO window. |
| The default value is 256 bytes. |
| cbmemsize=nn[KMG] The fixed amount of bus space which is |
| reserved for the CardBus bridge's memory |
| window. The default value is 64 megabytes. |
| |
| pcmv= [HW,PCMCIA] BadgePAD 4 |
| |
| pd. [PARIDE] |
| See Documentation/paride.txt. |
| |
| pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at |
| boot time. |
| Format: { 0 | 1 } |
| See arch/parisc/kernel/pdc_chassis.c |
| |
| pf. [PARIDE] |
| See Documentation/paride.txt. |
| |
| pg. [PARIDE] |
| See Documentation/paride.txt. |
| |
| pirq= [SMP,APIC] Manual mp-table setup |
| See Documentation/i386/IO-APIC.txt. |
| |
| plip= [PPT,NET] Parallel port network link |
| Format: { parport<nr> | timid | 0 } |
| See also Documentation/parport.txt. |
| |
| pnpacpi= [ACPI] |
| { off } |
| |
| pnpbios= [ISAPNP] |
| { on | off | curr | res | no-curr | no-res } |
| |
| pnp_reserve_irq= |
| [ISAPNP] Exclude IRQs for the autoconfiguration |
| |
| pnp_reserve_dma= |
| [ISAPNP] Exclude DMAs for the autoconfiguration |
| |
| pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration |
| Ranges are in pairs (I/O port base and size). |
| |
| pnp_reserve_mem= |
| [ISAPNP] Exclude memory regions for the |
| autoconfiguration. |
| Ranges are in pairs (memory base and size). |
| |
| print-fatal-signals= |
| [KNL] debug: print fatal signals |
| print-fatal-signals=1: print segfault info to |
| the kernel console. |
| default: off. |
| |
| printk.time= Show timing data prefixed to each printk message line |
| Format: <bool> (1/Y/y=enable, 0/N/n=disable) |
| |
| profile= [KNL] Enable kernel profiling via /proc/profile |
| Format: [schedule,]<number> |
| Param: "schedule" - profile schedule points. |
| Param: <number> - step/bucket size as a power of 2 for |
| statistical time based profiling. |
| Param: "sleep" - profile D-state sleeping (millisecs). |
| Requires CONFIG_SCHEDSTATS |
| Param: "kvm" - profile VM exits. |
| |
| processor.max_cstate= [HW,ACPI] |
| Limit processor to maximum C-state |
| max_cstate=9 overrides any DMI blacklist limit. |
| |
| processor.nocst [HW,ACPI] |
| Ignore the _CST method to determine C-states, |
| instead using the legacy FADT method |
| |
| prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk |
| before loading. |
| See Documentation/ramdisk.txt. |
| |
| psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to |
| probe for; one of (bare|imps|exps|lifebook|any). |
| psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports |
| per second. |
| psmouse.resetafter= [HW,MOUSE] |
| Try to reset the device after so many bad packets |
| (0 = never). |
| psmouse.resolution= |
| [HW,MOUSE] Set desired mouse resolution, in dpi. |
| psmouse.smartscroll= |
| [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/paride.txt. |
| |
| pty.legacy_count= |
| [KNL] Number of legacy pty's. Overwrites compiled-in |
| default number. |
| |
| quiet [KNL] Disable most log messages |
| |
| r128= [HW,DRM] |
| |
| raid= [HW,RAID] |
| See Documentation/md.txt. |
| |
| ramdisk_blocksize= [RAM] |
| See Documentation/ramdisk.txt. |
| |
| ramdisk_size= [RAM] Sizes of RAM disks in kilobytes |
| See Documentation/ramdisk.txt. |
| |
| rcupdate.blimit= [KNL,BOOT] |
| Set maximum number of finished RCU callbacks to process |
| in one batch. |
| |
| rcupdate.qhimark= [KNL,BOOT] |
| Set threshold of queued |
| RCU callbacks over which batch limiting is disabled. |
| |
| rcupdate.qlowmark= [KNL,BOOT] |
| Set threshold of queued RCU callbacks below which |
| batch limiting is re-enabled. |
| |
| rdinit= [KNL] |
| Format: <full_path> |
| Run specified binary instead of /init from the ramdisk, |
| used for early userspace startup. See initrd. |
| |
| reboot= [BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode |
| Format: <reboot_mode>[,<reboot_mode2>[,...]] |
| See arch/*/kernel/reboot.c or arch/*/kernel/process.c |
| |
| reserve= [KNL,BUGS] Force the kernel to ignore some iomem area |
| |
| reservetop= [X86-32] |
| Format: nn[KMG] |
| Reserves a hole at the top of the kernel virtual |
| address space. |
| |
| reset_devices [KNL] Force drivers to reset the underlying device |
| during initialization. |
| |
| resume= [SWSUSP] |
| Specify the partition device for software suspend |
| |
| resume_offset= [SWSUSP] |
| Specify the offset from the beginning of the partition |
| given by "resume=" at which the swap header is located, |
| in <PAGE_SIZE> units (needed only for swap files). |
| See Documentation/power/swsusp-and-swap-files.txt |
| |
| retain_initrd [RAM] Keep initrd memory after extraction |
| |
| rhash_entries= [KNL,NET] |
| Set number of hash buckets for route cache |
| |
| riscom8= [HW,SERIAL] |
| Format: <io_board1>[,<io_board2>[,...<io_boardN>]] |
| |
| ro [KNL] Mount root device read-only on boot |
| |
| root= [KNL] Root filesystem |
| |
| rootdelay= [KNL] Delay (in seconds) to pause before attempting to |
| mount the root filesystem |
| |
| rootflags= [KNL] Set root filesystem mount option string |
| |
| rootfstype= [KNL] Set root filesystem type |
| |
| rootwait [KNL] Wait (indefinitely) for root device to show up. |
| Useful for devices that are detected asynchronously |
| (e.g. USB and MMC devices). |
| |
| root_plug.vendor_id= |
| [ROOTPLUG] Override the default vendor ID |
| |
| root_plug.product_id= |
| [ROOTPLUG] Override the default product ID |
| |
| root_plug.debug= |
| [ROOTPLUG] Enable debugging output |
| |
| rw [KNL] Mount root device read-write on boot |
| |
| S [KNL] Run init in single mode |
| |
| sa1100ir [NET] |
| See drivers/net/irda/sa1100_ir.c. |
| |
| sbni= [NET] Granch SBNI12 leased line adapter |
| |
| sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver |
| Format: <io>[,<timeout>[,<isapnp>]] |
| |
| 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. |
| |
| selinux [SELINUX] Disable or enable SELinux at boot time. |
| Format: { "0" | "1" } |
| See security/selinux/Kconfig help text. |
| 0 -- disable. |
| 1 -- enable. |
| Default value is set via kernel config option. |
| If enabled at boot time, /selinux/disable can be used |
| later to disable prior to initial policy load. |
| |
| selinux_compat_net = |
| [SELINUX] Set initial selinux_compat_net flag value. |
| Format: { "0" | "1" } |
| 0 -- use new secmark-based packet controls |
| 1 -- use legacy packet controls |
| Default value is 0 (preferred). |
| Value can be changed at runtime via |
| /selinux/compat_net. |
| |
| serialnumber [BUGS=X86-32] |
| |
| shapers= [NET] |
| Maximal number of shapers. |
| |
| sim710= [SCSI,HW] |
| See header of drivers/scsi/sim710.c. |
| |
| simeth= [IA-64] |
| simscsi= |
| |
| slram= [HW,MTD] |
| |
| slub_debug[=options[,slabs]] [MM, SLUB] |
| Enabling slub_debug allows one to determine the |
| culprit if slab objects become corrupted. Enabling |
| slub_debug can create guard zones around objects and |
| may poison objects when not in use. Also tracks the |
| last alloc / free. For more information see |
| Documentation/vm/slub.txt. |
| |
| slub_max_order= [MM, SLUB] |
| Determines the maximum allowed order for slabs. |
| A high setting may cause OOMs due to memory |
| fragmentation. For more information see |
| Documentation/vm/slub.txt. |
| |
| slub_min_objects= [MM, SLUB] |
| The minimum number of objects per slab. SLUB will |
| increase the slab order up to slub_max_order to |
| generate a sufficiently large slab able to contain |
| the number of objects indicated. The higher the number |
| of objects the smaller the overhead of tracking slabs |
| and the less frequently locks need to be acquired. |
| For more information see Documentation/vm/slub.txt. |
| |
| slub_min_order= [MM, SLUB] |
| Determines the mininum page order for slabs. Must be |
| lower than slub_max_order. |
| For more information see Documentation/vm/slub.txt. |
| |
| slub_nomerge [MM, SLUB] |
| Disable merging of slabs with similar size. May be |
| necessary if there is some reason to distinguish |
| allocs to different slabs. Debug options disable |
| merging on their own. |
| For more information see Documentation/vm/slub.txt. |
| |
| smart2= [HW] |
| Format: <io1>[,<io2>[,...,<io8>]] |
| |
| smp-alt-once [X86-32,SMP] On a hotplug CPU system, only |
| attempt to substitute SMP alternatives once at boot. |
| |
| smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices |
| smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port |
| smsc-ircc2.ircc_sir= [HW] SIR base I/O port |
| smsc-ircc2.ircc_fir= [HW] FIR base I/O port |
| smsc-ircc2.ircc_irq= [HW] IRQ line |
| smsc-ircc2.ircc_dma= [HW] DMA channel |
| smsc-ircc2.ircc_transceiver= [HW] Transceiver type: |
| 0: Toshiba Satellite 1800 (GP data pin select) |
| 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] |
| |
| sonypi.*= [HW] Sony Programmable I/O Control Device driver |
| See Documentation/sonypi.txt |
| |
| specialix= [HW,SERIAL] Specialix multi-serial port adapter |
| See Documentation/specialix.txt. |
| |
| spia_io_base= [HW,MTD] |
| spia_fio_base= |
| 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. |
| |
| sti= [PARISC,HW] |
| Format: <num> |
| Set the STI (builtin display/keyboard on the HP-PARISC |
| machines) console (graphic card) which should be used |
| as the initial boot-console. |
| See also comment in drivers/video/console/sticore.c. |
| |
| sti_font= [HW] |
| See comment in drivers/video/console/sticore.c. |
| |
| stifb= [HW] |
| Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]] |
| |
| sunrpc.pool_mode= |
| [NFS] |
| Control how the NFS server code allocates CPUs to |
| service thread pools. Depending on how many NICs |
| you have and where their interrupts are bound, this |
| option will affect which CPUs will do NFS serving. |
| Note: this parameter cannot be changed while the |
| NFS server is running. |
| |
| auto the server chooses an appropriate mode |
| automatically using heuristics |
| global a single global pool contains all CPUs |
| percpu one pool for each CPU |
| pernode one pool for each NUMA node (equivalent |
| to global on non-NUMA machines) |
| |
| swiotlb= [IA-64] Number of I/O TLB slabs |
| |
| 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] |
| |
| thash_entries= [KNL,NET] |
| Set number of hash buckets for TCP connection |
| |
| thermal.act= [HW,ACPI] |
| -1: disable all active trip points in all thermal zones |
| <degrees C>: override all lowest active trip points |
| |
| thermal.crt= [HW,ACPI] |
| -1: disable all critical trip points in all thermal zones |
| <degrees C>: lower all critical trip points |
| |
| thermal.nocrt= [HW,ACPI] |
| Set to disable actions on ACPI thermal zone |
| critical and hot trip points. |
| |
| thermal.off= [HW,ACPI] |
| 1: disable ACPI thermal control |
| |
| thermal.psv= [HW,ACPI] |
| -1: disable all passive trip points |
| <degrees C>: override all passive trip points to this value |
| |
| thermal.tzp= [HW,ACPI] |
| Specify global default ACPI thermal zone polling rate |
| <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. |
| |
| tp720= [HW,PS2] |
| |
| trix= [HW,OSS] MediaTrix AudioTrix Pro |
| Format: |
| <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq> |
| |
| turbografx.map[2|3]= [HW,JOY] |
| TurboGraFX parallel port interface |
| Format: |
| <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> |
| |
| uhci-hcd.ignore_oc= |
| [USB] Ignore overcurrent events (default N). |
| Some badly-designed motherboards generate lots of |
| bogus events, for ports that aren't wired to |
| anything. Set this parameter to avoid log spamming. |
| Note that genuine overcurrent events won't be |
| reported either. |
| |
| usbcore.autosuspend= |
| [USB] The autosuspend time delay (in seconds) used |
| for newly-detected USB devices (default 2). This |
| is the time required before an idle device will be |
| autosuspended. Devices for which the delay is set |
| to a negative value won't be autosuspended at all. |
| |
| usbhid.mousepoll= |
| [USBHID] The interval which mice are to be polled at. |
| |
| vdso= [X86-32,SH,x86-64] |
| 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=2: enable compat VDSO (default with COMPAT_VDSO) |
| vdso32=1: enable 32-bit VDSO (default) |
| vdso32=0: disable 32-bit VDSO mapping |
| |
| vector= [IA-64,SMP] |
| vector=percpu: enable percpu vector domain |
| |
| video= [FB] Frame buffer configuration |
| See Documentation/fb/modedb.txt. |
| |
| vga= [BOOT,X86-32] Select a particular video mode |
| See Documentation/i386/boot.txt and |
| Documentation/svga.txt. |
| Use vga=ask for menu. |
| This is actually a boot loader parameter; the value is |
| passed to the kernel using a special protocol. |
| |
| vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact |
| size of <nn>. This can be used to increase the |
| minimum size (128MB on x86). It can also be used to |
| decrease the size and leave more room for directly |
| mapped kernel RAM. |
| |
| vmhalt= [KNL,S390] Perform z/VM CP command after system halt. |
| Format: <command> |
| |
| vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic. |
| Format: <command> |
| |
| vmpoff= [KNL,S390] Perform z/VM CP command after power off. |
| Format: <command> |
| |
| 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. |
| |
| wdt= [WDT] Watchdog |
| See Documentation/watchdog/wdt.txt. |
| |
| xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks. |
| xd_geo= See header of drivers/block/xd.c. |
| |
| xirc2ps_cs= [NET,PCMCIA] |
| Format: |
| <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]] |
| |
| norandmaps Don't use address space randomization |
| Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space |
| |
| ______________________________________________________________________ |
| |
| TODO: |
| |
| Add documentation for ALSA options. |
| Add more DRM drivers. |