Merge branch 'drm-fixes' of master.kernel.org:/pub/scm/linux/kernel/git/airlied/drm-2.6

[mirror_ubuntu-zesty-kernel.git] / Documentation / kernel-parameters.txt

February 2003             Kernel Parameters                     v2.5.59
                          ~~~~~~~~~~~~~~~~~

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

The text in square brackets at the beginning of the description state the
restrictions on the kernel for the said kernel parameter to be valid. The
restrictions referred to are that the relevant option is valid if:

        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.
        DEVFS   devfs 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.
        MTD     MTD support is enabled.
        NET     Appropriate network support is enabled.
        NUMA    NUMA support 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 suspension 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.

        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 }
                        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_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
                        over-ride platform specific driver.
                        See also Documentation/acpi-hotkey.txt.

        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.

        AM53C974=       [HW,SCSI]
                        Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
                        See also header of drivers/scsi/AM53C974.c.

        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]

        awe=            [HW,OSS] AWE32/SB32/AWE64 wave table synth
                        Format: <io>,<memsize>,<isapnp>
 
        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 timesource override. 
                        Forces specified timesource (if avaliable) to be used
                        when calculating gettimeofday(). If specicified timesource
                        is not avalible, it defaults to PIT. 
                        Format: { pit | tsc | cyclone | pmtmr }

        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]
                        Use the specified serial port.  The options are of
                        the form "bbbbpn", where "bbbb" is the baud rate,
                        "p" is parity ("n", "o", or "e"), and "n" is bits.
                        Default is "9600n8".

                        See also Documentation/serial-console.txt.

                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).

        decnet=         [HW,NET]
                        Format: <area>[,<node>]
                        See also Documentation/networking/decnet.txt.

        devfs=          [DEVFS]
                        See Documentation/filesystems/devfs/boot-options.

        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]

        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: {"as"|"cfq"|"deadline"|"noop"}
                        See Documentation/block/as-iosched.txt
                        and Documentation/block/deadline-iosched.txt for details.
        elfcorehdr=     [IA-32]
                        Specifies physical address of start of kernel core image
                        elf header.
                        See Documentation/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.

        es1370=         [HW,OSS]
                        Format: <lineout>[,<micbias>]
                        See also header of sound/oss/es1370.c.

        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>

        gt96100eth=     [NET] MIPS GT96100 Advanced Communication Controller

        gus=            [HW,OSS]
                        Format: <io>,<irq>,<dma>,<dma16>
 
        gvp11=          [HW,SCSI]

        hashdist=       [KNL,NUMA] Large hashes allocated during boot
                        are distributed across NUMA nodes.  Defaults on
                        for IA-64, off otherwise.

        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 controlled can only read data from
                             keyboard and can not control its state
                             (Don't attempt to blink the leds)
        i8042.noaux     [HW] Don't check for auxiliary (== mouse) 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>

        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.

        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.udpport=  [NFS]

        lockd.tcpport=  [NFS]

        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 is n, nk, nM.  n must be a power of two.  The
                        default is set in kernel config.

        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

        mad16=          [HW,OSS]
                        Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>

        maui=           [HW,OSS]
                        Format: <io>,<irq>
 
        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] 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]

        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.
 
        nfsaddrs=       [NFS]
                        See Documentation/nfsroot.txt.

        nfsroot=        [NFS] nfs root filesystem for disk-less boxes.
                        See Documentation/nfsroot.txt.

        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]
 
        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]

        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.

        nomce           [IA-32] Machine Check Exception

        noresidual      [PPC] Don't use residual data on PReP machines.

        noresume        [SWSUSP] Disables resume and restore 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]

        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]
 
        opl3=           [HW,OSS]
                        Format: <io>

        opl3sa=         [HW,OSS]
                        Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>

        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=0       [HW,PPT]        Specify parallel ports. 0 disables.
        parport=auto                    Use 'auto' to force the driver to use
        parport=0xBBB[,IRQ[,DMA]]       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 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.

        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.
                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 till 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.

        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
                        { schedule | <number> }
                        (param: schedule - profile schedule points}
                        (param: profile 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.

        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 (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 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.

        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.

        reserve=        [KNL,BUGS] Force the kernel to ignore some iomem area

        resume=         [SWSUSP] Specify the partition device for software suspension

        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.

        serialnumber    [BUGS=IA-32]

        sg_def_reserved_size=
                        [SCSI]
 
        sgalaxy=        [HW,OSS]
                        Format: <io>,<irq>,<dma>,<dma2>,<sgbase>

        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]
 
        sonicvibes=     [HW,OSS]
                        Format: <reverb>
 
        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>...]]

        stram_swap=     [HW,M68k]

        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

        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>

        usb-handoff     [HW] Enable early USB BIOS -> OS handoff

        usbhid.mousepoll=
                        [USBHID] The interval which mice are to be polled at.
 
        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]

        vmpoff=         [KNL,S390] 
 
        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>]]]



Changelog:

        The last known update (for 2.4.0) - the changelog was not kept before.
        2000-06-??      Mr. Unknown

        Update for 2.5.49, description for most of the options introduced,
        references to other documentation (C files, READMEs, ..), added S390,
        PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
        reformatting.
        2002-11-24      Petr Baudis <pasky@ucw.cz>
                        Randy Dunlap <randy.dunlap@verizon.net>

TODO:

        Add documentation for ALSA options.
        Add more DRM drivers.