|  | 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. | 
|  | ALSA	ALSA sound support is enabled. | 
|  | APIC	APIC support is enabled. | 
|  | APM	Advanced Power Management support is enabled. | 
|  | AX25	Appropriate AX.25 support is enabled. | 
|  | CD	Appropriate CD support 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-32	IA-32 aka i386 architecture 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. | 
|  | 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 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. | 
|  | PARIDE	The ParIDE subsystem is enabled. | 
|  | PARISC	The PA-RISC architecture is enabled. | 
|  | PCI	PCI bus 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. | 
|  | S390	S390 architecture is enabled. | 
|  | SCSI	Appropriate SCSI support is enabled. | 
|  | A lot of drivers has their options described inside of | 
|  | Documentation/scsi/. | 
|  | SELINUX SELinux support is enabled. | 
|  | SERIAL	Serial support 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. | 
|  | X86-64	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>. | 
|  |  | 
|  | 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. | 
|  |  | 
|  |  | 
|  | 53c7xx=		[HW,SCSI] Amiga SCSI controllers | 
|  | See header of drivers/scsi/53c7xx.c. | 
|  | See also Documentation/scsi/ncr53c7xx.txt. | 
|  |  | 
|  | acpi=		[HW,ACPI] 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/pm.txt, pci=noacpi | 
|  |  | 
|  | acpi_sleep=	[HW,ACPI] Sleep options | 
|  | Format: { s3_bios, s3_mode } | 
|  | See Documentation/power/video.txt | 
|  |  | 
|  | 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_os_name=	[HW,ACPI] Tell ACPI BIOS the name of the OS | 
|  | Format: To spoof as Windows 98: ="Microsoft Windows" | 
|  |  | 
|  | acpi_osi=	[HW,ACPI] empty param disables _OSI | 
|  |  | 
|  | 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_dbg_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 /proc/acpi/debug_layer. | 
|  |  | 
|  | acpi_dbg_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 /proc/acpi/debug_level. | 
|  |  | 
|  | acpi_fake_ecdt	[HW,ACPI] Workaround failure due to BIOS lacking ECDT | 
|  |  | 
|  | acpi_generic_hotkey [HW,ACPI] | 
|  | Allow consolidated generic hotkey driver to | 
|  | override platform specific driver. | 
|  | See also Documentation/acpi-hotkey.txt. | 
|  |  | 
|  | acpi_pm_good	[IA-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. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | ad1816=		[HW,OSS] | 
|  | Format: <io>,<irq>,<dma>,<dma2> | 
|  | See also Documentation/sound/oss/AD1816. | 
|  |  | 
|  | ad1848=		[HW,OSS] | 
|  | Format: <io>,<irq>,<dma>,<dma2>,<type> | 
|  |  | 
|  | adlib=		[HW,OSS] | 
|  | Format: <io> | 
|  |  | 
|  | 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] 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. | 
|  |  | 
|  | applicom=	[HW] | 
|  | Format: <mem>,<irq> | 
|  |  | 
|  | 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] | 
|  |  | 
|  | aztcd=		[HW,CD] Aztech CD268 CDROM driver | 
|  | Format: <io>,0x79 (?) | 
|  |  | 
|  | 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. | 
|  |  | 
|  | blkmtd_device=	[HW,MTD] | 
|  | blkmtd_erasesz= | 
|  | blkmtd_ro= | 
|  | blkmtd_bs= | 
|  | blkmtd_count= | 
|  |  | 
|  | 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=IA-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. | 
|  |  | 
|  | cdu31a=		[HW,CD] | 
|  | Format: <io>,<irq>[,PAS] | 
|  | See header of drivers/cdrom/cdu31a.c. | 
|  |  | 
|  | chandev=	[HW,NET] Generic channel device initialisation | 
|  |  | 
|  | 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. | 
|  |  | 
|  | clock=		[BUGS=IA-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 } | 
|  |  | 
|  | 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=		[IA-32,HPET] option to disable HPET and use PIT. | 
|  | Format: disable | 
|  |  | 
|  | cm206=		[HW,CD] | 
|  | Format: { auto | [<io>,][<irq>] } | 
|  |  | 
|  | 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,io,<addr>[,options] | 
|  | uart,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. | 
|  |  | 
|  | cpcihp_generic=	[HW,PCI] Generic port I/O CompactPCI driver | 
|  | Format: | 
|  | <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] | 
|  |  | 
|  | cpia_pp=	[HW,PPT] | 
|  | Format: { parport<nr> | auto | none } | 
|  |  | 
|  | crashkernel=nn[KMG]@ss[KMG] | 
|  | [KNL] Reserve a chunk of physical memory to | 
|  | hold a kernel to switch to with kexec on panic. | 
|  |  | 
|  | cs4232=		[HW,OSS] | 
|  | Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq> | 
|  |  | 
|  | cs89x0_dma=	[HW,NET] | 
|  | Format: <dma> | 
|  |  | 
|  | cs89x0_media=	[HW,NET] | 
|  | Format: { rj45 | aui | bnc } | 
|  |  | 
|  | cyclades=	[HW,SERIAL] Cyclades multi-serial port adapter. | 
|  |  | 
|  | 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=		[HW,NET] | 
|  | Format: <area>[,<node>] | 
|  | See also Documentation/networking/decnet.txt. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | dmascc=		[HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA | 
|  | support available. | 
|  | Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]] | 
|  |  | 
|  | dmasound=	[HW,OSS] Sound subsystem buffers | 
|  |  | 
|  | dscc4.setup=	[NET] | 
|  |  | 
|  | dtc3181e=	[HW,SCSI] | 
|  |  | 
|  | earlyprintk=	[IA-32,X86-64] | 
|  | 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] | 
|  |  | 
|  | ec_intr=	[HW,ACPI] ACPI Embedded Controller interrupt mode | 
|  | Format: <int> | 
|  | 0: polling mode | 
|  | non-0: interrupt mode (default) | 
|  |  | 
|  | eda=		[HW,PS2] | 
|  |  | 
|  | edb=		[HW,PS2] | 
|  |  | 
|  | edd=		[EDD] | 
|  | Format: {"of[f]" | "sk[ipmbr]"} | 
|  | See comment in arch/i386/boot/edd.S | 
|  |  | 
|  | eicon=		[HW,ISDN] | 
|  | Format: <id>,<membase>,<irq> | 
|  |  | 
|  | eisa_irq_edge=	[PARISC,HW] | 
|  | See header of drivers/parisc/eisa.c. | 
|  |  | 
|  | elanfreq=	[IA-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=	[IA-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>] | 
|  |  | 
|  | 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. | 
|  |  | 
|  | ftape=		[HW] Floppy Tape subsystem debugging options. | 
|  | See Documentation/ftape.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] | 
|  |  | 
|  | 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. | 
|  |  | 
|  | gscd=		[HW,CD] | 
|  | Format: <io> | 
|  |  | 
|  | 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.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. | 
|  |  | 
|  | hisax=		[HW,ISDN] | 
|  | See Documentation/isdn/README.HiSax. | 
|  |  | 
|  | hugepages=	[HW,IA-32,IA-64] Maximal number of HugeTLB pages. | 
|  |  | 
|  | noirqbalance	[IA-32,SMP,KNL] Disable kernel irq balancing | 
|  |  | 
|  | 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.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 or ide=reverse | 
|  | See Documentation/ide.txt. | 
|  |  | 
|  | ide?=		[HW] (E)IDE subsystem | 
|  | Format: ide?=noprobe or chipset specific parameters. | 
|  | See Documentation/ide.txt. | 
|  |  | 
|  | idebus=		[HW] (E)IDE subsystem - VLB/PCI bus speed | 
|  | See Documentation/ide.txt. | 
|  |  | 
|  | idle=		[HW] | 
|  | Format: idle=poll or idle=halt | 
|  |  | 
|  | 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> | 
|  |  | 
|  | combined_mode=	[HW] control which driver uses IDE ports in combined | 
|  | mode: legacy IDE driver, libata, or both | 
|  | (in the libata case, libata.atapi_enabled=1 may be | 
|  | useful as well).  Note that using the ide or libata | 
|  | options may affect your device naming (e.g. by | 
|  | changing hdc to sdb). | 
|  | Format: combined (default), ide, or libata | 
|  |  | 
|  | inttest=	[IA64] | 
|  |  | 
|  | 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/nfsroot.txt. | 
|  |  | 
|  | ip2=		[HW] Set IO/IRQ pairs for up to 4 IntelliPort boards | 
|  | See comment before ip2_setup() in drivers/char/ip2.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> | 
|  | 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. | 
|  |  | 
|  | isp16=		[HW,CD] | 
|  | Format: <io>,<irq>,<dma>,<setup> | 
|  |  | 
|  | iucv=		[HW,NET] | 
|  |  | 
|  | js=		[HW,JOY] Analog joystick | 
|  | See Documentation/input/joystick.txt. | 
|  |  | 
|  | keepinitrd	[HW,ARM] | 
|  |  | 
|  | kstack=N	[IA-32,X86-64] Print N words from the kernel stack | 
|  | in oops dumps. | 
|  |  | 
|  | l2cr=		[PPC] | 
|  |  | 
|  | lapic		[IA-32,APIC] Enable the local APIC even if BIOS | 
|  | disabled it. | 
|  |  | 
|  | lasi=		[HW,SCSI] PARISC LASI driver for the 53c700 chip | 
|  | Format: addr:<io>,irq:<irq> | 
|  |  | 
|  | llsc*=		[IA64] See function print_params() in | 
|  | arch/ia64/sn/kernel/llsc4.c. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | 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 | 
|  |  | 
|  | 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. | 
|  |  | 
|  | mca-pentium	[BUGS=IA-32] | 
|  |  | 
|  | mcatest=	[IA-64] | 
|  |  | 
|  | mcd=		[HW,CD] | 
|  | Format: <port>,<irq>,<mitsumi_bug_93_wait> | 
|  |  | 
|  | mcdx=		[HW,CD] | 
|  |  | 
|  | mce		[IA-32] Machine Check Exception | 
|  |  | 
|  | 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. | 
|  | [IA-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=IA-32] Disable usage of 4MB pages for kernel | 
|  | memory. | 
|  |  | 
|  | memmap=exactmap	[KNL,IA-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. | 
|  |  | 
|  | meye.*=		[HW] Set MotionEye Camera parameters | 
|  | See Documentation/video4linux/meye.txt. | 
|  |  | 
|  | mga=		[HW,DRM] | 
|  |  | 
|  | migration_cost= | 
|  | [KNL,SMP] debug: override scheduler migration costs | 
|  | Format: <level-1-usecs>,<level-2-usecs>,... | 
|  | This debugging option can be used to override the | 
|  | default scheduler migration cost matrix. The numbers | 
|  | are indexed by 'CPU domain distance'. | 
|  | E.g. migration_cost=1000,2000,3000 on an SMT NUMA | 
|  | box will set up an intra-core migration cost of | 
|  | 1 msec, an inter-core migration cost of 2 msecs, | 
|  | and an inter-node migration cost of 3 msecs. | 
|  |  | 
|  | WARNING: using the wrong values here can break | 
|  | scheduler performance, so it's only for scheduler | 
|  | development purposes, not production environments. | 
|  |  | 
|  | migration_debug= | 
|  | [KNL,SMP] migration cost auto-detect verbosity | 
|  | Format=<0|1|2> | 
|  | If a system's migration matrix reported at bootup | 
|  | seems erroneous then this option can be used to | 
|  | increase verbosity of the detection process. | 
|  | We default to 0 (no extra messages), 1 will print | 
|  | some more information, and 2 will be really | 
|  | verbose (probably only useful if you also have a | 
|  | serial console attached to the system). | 
|  |  | 
|  | migration_factor= | 
|  | [KNL,SMP] multiply/divide migration costs by a factor | 
|  | Format=<percent> | 
|  | This debug option can be used to proportionally | 
|  | increase or decrease the auto-detected migration | 
|  | costs for all entries of the migration matrix. | 
|  | E.g. migration_factor=150 will increase migration | 
|  | costs by 50%. (and thus the scheduler will be less | 
|  | eager migrating cache-hot tasks) | 
|  | migration_factor=80 will decrease migration costs | 
|  | by 20%. (thus the scheduler will be more eager to | 
|  | migrate tasks) | 
|  |  | 
|  | WARNING: using the wrong values here can break | 
|  | scheduler performance, so it's only for scheduler | 
|  | development purposes, not production environments. | 
|  |  | 
|  | 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/cmdline.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/nfsroot.txt. | 
|  |  | 
|  | nfsroot=	[NFS] nfs root filesystem for disk-less boxes. | 
|  | See Documentation/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. | 
|  |  | 
|  | nmi_watchdog=	[KNL,BUGS=IA-32] Debugging features for SMP kernels | 
|  |  | 
|  | no387		[BUGS=IA-32] Tells the kernel to use the 387 maths | 
|  | emulation library even if a 387 maths coprocessor | 
|  | is present. | 
|  |  | 
|  | noalign		[KNL,ARM] | 
|  |  | 
|  | noapic		[SMP,APIC] Tells the kernel to not make use of any | 
|  | IOAPICs that may be present in the system. | 
|  |  | 
|  | noasync		[HW,M68K] Disables async and sync negotiation for | 
|  | all devices. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | noexec		[IA-64] | 
|  |  | 
|  | noexec		[IA-32,X86-64] | 
|  | noexec=on: enable non-executable mappings (default) | 
|  | noexec=off: disable nn-executable mappings | 
|  |  | 
|  | nofxsr		[BUGS=IA-32] Disables x86 floating point extended | 
|  | register save and restore. The kernel will only save | 
|  | legacy floating-point registers on task switch. | 
|  |  | 
|  | nohlt		[BUGS=ARM] | 
|  |  | 
|  | no-hlt		[BUGS=IA-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. | 
|  |  | 
|  | noirqdebug	[IA-32] Disables the code which attempts to detect and | 
|  | disable unhandled interrupt sources. | 
|  |  | 
|  | noisapnp	[ISAPNP] Disables ISA PnP code. | 
|  |  | 
|  | noinitrd	[RAM] Tells the kernel not to load any configured | 
|  | initial RAM disk. | 
|  |  | 
|  | nointroute	[IA-64] | 
|  |  | 
|  | nolapic		[IA-32,APIC] Do not enable or use the local APIC. | 
|  |  | 
|  | noltlbs		[PPC] Do not use large page/tlb entries for kernel | 
|  | lowmem mapping on PPC40x. | 
|  |  | 
|  | nomca		[IA-64] Disable machine check abort handling | 
|  |  | 
|  | nomce		[IA-32] Machine Check Exception | 
|  |  | 
|  | 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=IA-32] Disables x86 SYSENTER/SYSEXIT support. | 
|  |  | 
|  | nosmp		[SMP] Tells an SMP kernel to act as a UP kernel. | 
|  |  | 
|  | nosync		[HW,M68K] Disables sync negotiation for all devices. | 
|  |  | 
|  | notsc		[BUGS=IA-32] Disable Time Stamp Counter | 
|  |  | 
|  | nousb		[USB] Disable the USB subsystem | 
|  |  | 
|  | nowb		[ARM] | 
|  |  | 
|  | nr_uarts=	[SERIAL] maximum number of UARTs to be registered. | 
|  |  | 
|  | opl3=		[HW,OSS] | 
|  | Format: <io> | 
|  |  | 
|  | opl3sa2=	[HW,OSS] Format: | 
|  | <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple] | 
|  |  | 
|  | oprofile.timer=	[HW] | 
|  | Use timer interrupt instead of performance counters | 
|  |  | 
|  | optcd=		[HW,CD] | 
|  | Format: <io> | 
|  |  | 
|  | 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		[IA-32] don't probe for the PCI bus | 
|  | bios		[IA-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		[IA-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		[IA-32] Force use of PCI Configuration | 
|  | Mechanism 1. | 
|  | conf2		[IA-32] Force use of PCI Configuration | 
|  | Mechanism 2. | 
|  | nommconf	[IA-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. | 
|  | nosort		[IA-32] Don't sort PCI devices according to | 
|  | order given by the PCI BIOS. This sorting is | 
|  | done to get a device order compatible with | 
|  | older kernels. | 
|  | biosirq		[IA-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		[IA-32] Assign address space to expansion ROMs. | 
|  | Use with caution as certain devices share | 
|  | address decoders between ROMs and other | 
|  | resources. | 
|  | irqmask=0xMMMM	[IA-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	[IA-32] Specify the physical address | 
|  | of the PIRQ table (normally generated | 
|  | by the BIOS) if it is outside the | 
|  | F0000h-100000h range. | 
|  | lastbus=N	[IA-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	[IA-32] Always assign all PCI bus | 
|  | numbers ourselves, overriding | 
|  | whatever the firmware may have done. | 
|  | usepirqmask	[IA-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		[IA-32] Do not use ACPI for IRQ routing | 
|  | or for PCI scanning. | 
|  | 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. | 
|  |  | 
|  | 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). | 
|  |  | 
|  | 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. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | quiet		[KNL] Disable most log messages | 
|  |  | 
|  | r128=		[HW,DRM] | 
|  |  | 
|  | raid=		[HW,RAID] | 
|  | See Documentation/md.txt. | 
|  |  | 
|  | ramdisk=	[RAM] Sizes of RAM disks in kilobytes [deprecated] | 
|  | See Documentation/ramdisk.txt. | 
|  |  | 
|  | ramdisk_blocksize=	[RAM] | 
|  | See Documentation/ramdisk.txt. | 
|  |  | 
|  | ramdisk_size=	[RAM] Sizes of RAM disks in kilobytes | 
|  | New name for the ramdisk parameter. | 
|  | See Documentation/ramdisk.txt. | 
|  |  | 
|  | rcu.blimit=	[KNL,BOOT] Set maximum number of finished | 
|  | RCU callbacks to process in one batch. | 
|  |  | 
|  | rcu.qhimark=	[KNL,BOOT] Set threshold of queued | 
|  | RCU callbacks over which batch limiting is disabled. | 
|  |  | 
|  | rcu.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=IA-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=	[IA-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 | 
|  |  | 
|  | 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 | 
|  |  | 
|  | 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. | 
|  |  | 
|  | sb=		[HW,OSS] | 
|  | Format: <io>,<irq>,<dma>,<dma2> | 
|  |  | 
|  | sbni=		[NET] Granch SBNI12 leased line adapter | 
|  |  | 
|  | sbpcd=		[HW,CD] Soundblaster CD adapter | 
|  | Format: <io>,<type> | 
|  | See a comment before function sbpcd_setup() in | 
|  | drivers/cdrom/sbpcd.c. | 
|  |  | 
|  | 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=	[SCSI] | 
|  |  | 
|  | 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=IA-32] | 
|  |  | 
|  | sg_def_reserved_size=	[SCSI] | 
|  |  | 
|  | shapers=	[NET] | 
|  | Maximal number of shapers. | 
|  |  | 
|  | sim710=		[SCSI,HW] | 
|  | See header of drivers/scsi/sim710.c. | 
|  |  | 
|  | simeth=		[IA-64] | 
|  | simscsi= | 
|  |  | 
|  | sjcd=		[HW,CD] | 
|  | Format: <io>,<irq>,<dma> | 
|  | See header of drivers/cdrom/sjcd.c. | 
|  |  | 
|  | slram=		[HW,MTD] | 
|  |  | 
|  | smart2=		[HW] | 
|  | Format: <io1>[,<io2>[,...,<io8>]] | 
|  |  | 
|  | 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] | 
|  |  | 
|  | sonycd535=	[HW,CD] | 
|  | Format: <io>[,<irq>] | 
|  |  | 
|  | 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. | 
|  |  | 
|  | st0x=		[HW,SCSI] | 
|  | See header of drivers/scsi/seagate.c. | 
|  |  | 
|  | 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>...]] | 
|  |  | 
|  | swiotlb=	[IA-64] Number of I/O TLB slabs | 
|  |  | 
|  | switches=	[HW,M68k] | 
|  |  | 
|  | sym53c416=	[HW,SCSI] | 
|  | See header of drivers/scsi/sym53c416.c. | 
|  |  | 
|  | 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 | 
|  |  | 
|  | time		Show timing data prefixed to each printk message line | 
|  |  | 
|  | clocksource=	[GENERIC_TIME] Override the default clocksource | 
|  | Override the default clocksource and use the clocksource | 
|  | with the name specified. | 
|  |  | 
|  | 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). | 
|  |  | 
|  | tmc8xx=		[HW,SCSI] | 
|  | See header of drivers/scsi/seagate.c. | 
|  |  | 
|  | 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> | 
|  |  | 
|  | tsdev.xres=	[TS] Horizontal screen resolution. | 
|  | tsdev.yres=	[TS] Vertical screen resolution. | 
|  |  | 
|  | 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> | 
|  |  | 
|  | usbhid.mousepoll= | 
|  | [USBHID] The interval which mice are to be polled at. | 
|  |  | 
|  | vdso=		[IA-32] | 
|  | vdso=1: enable VDSO (default) | 
|  | vdso=0: disable VDSO mapping | 
|  |  | 
|  | video=		[FB] Frame buffer configuration | 
|  | See Documentation/fb/modedb.txt. | 
|  |  | 
|  | vga=		[BOOT,IA-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/watchdog.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. |