4 The following is a consolidated list of the kernel parameters as implemented
5 (mostly) by the __setup() macro and sorted into English Dictionary order
6 (defined as ignoring all punctuation and sorting digits before letters in a
7 case insensitive manner), and with descriptions where known.
9 Module parameters for loadable modules are specified only as the
10 parameter name with optional '=' and value as appropriate, such as:
12 modprobe usbcore blinkenlights=1
14 Module parameters for modules that are built into the kernel image
15 are specified on the kernel command line with the module name plus
16 '.' plus parameter name, with '=' and value if appropriate, such as:
18 usbcore.blinkenlights=1
20 This document may not be entirely up to date and comprehensive. The command
21 "modinfo -p ${modulename}" shows a current list of all parameters of a loadable
22 module. Loadable modules, after being loaded into the running kernel, also
23 reveal their parameters in /sys/module/${modulename}/parameters/. Some of these
24 parameters may be changed at runtime by the command
25 "echo -n ${value} > /sys/module/${modulename}/parameters/${parm}".
27 The parameters listed below are only valid if certain kernel build options were
28 enabled and if respective hardware is present. The text in square brackets at
29 the beginning of each description states the restrictions within which a
30 parameter is applicable:
32 ACPI ACPI support is enabled.
33 ALSA ALSA sound support is enabled.
34 APIC APIC support is enabled.
35 APM Advanced Power Management support is enabled.
36 AX25 Appropriate AX.25 support is enabled.
37 CD Appropriate CD support is enabled.
38 DRM Direct Rendering Management support is enabled.
39 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
40 EFI EFI Partitioning (GPT) is enabled
41 EIDE EIDE/ATAPI support is enabled.
42 FB The frame buffer device is enabled.
43 HW Appropriate hardware is enabled.
44 IA-32 IA-32 aka i386 architecture is enabled.
45 IA-64 IA-64 architecture is enabled.
46 IOSCHED More than one I/O scheduler is enabled.
47 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
48 ISAPNP ISA PnP code is enabled.
49 ISDN Appropriate ISDN support is enabled.
50 JOY Appropriate joystick support is enabled.
51 LP Printer support is enabled.
52 LOOP Loopback device support is enabled.
53 M68k M68k architecture is enabled.
54 These options have more detailed description inside of
55 Documentation/m68k/kernel-options.txt.
56 MCA MCA bus support is enabled.
57 MDA MDA console support is enabled.
58 MOUSE Appropriate mouse support is enabled.
59 MSI Message Signaled Interrupts (PCI).
60 MTD MTD support is enabled.
61 NET Appropriate network support is enabled.
62 NUMA NUMA support is enabled.
63 GENERIC_TIME The generic timeofday code is enabled.
64 NFS Appropriate NFS support is enabled.
65 OSS OSS sound support is enabled.
66 PARIDE The ParIDE subsystem is enabled.
67 PARISC The PA-RISC architecture is enabled.
68 PCI PCI bus support is enabled.
69 PCMCIA The PCMCIA subsystem is enabled.
70 PNP Plug & Play support is enabled.
71 PPC PowerPC architecture is enabled.
72 PPT Parallel port support is enabled.
73 PS2 Appropriate PS/2 support is enabled.
74 RAM RAM disk support is enabled.
75 S390 S390 architecture is enabled.
76 SCSI Appropriate SCSI support is enabled.
77 A lot of drivers has their options described inside of
79 SELINUX SELinux support is enabled.
80 SERIAL Serial support is enabled.
81 SMP The kernel is an SMP kernel.
82 SPARC Sparc architecture is enabled.
83 SWSUSP Software suspend is enabled.
84 TS Appropriate touchscreen support is enabled.
85 USB USB support is enabled.
86 USBHID USB Human Interface Device support is enabled.
87 V4L Video For Linux support is enabled.
88 VGA The VGA console has been enabled.
89 VT Virtual terminal support is enabled.
90 WDT Watchdog support is enabled.
91 XT IBM PC/XT MFM hard disk support is enabled.
92 X86-64 X86-64 architecture is enabled.
93 More X86-64 boot options can be found in
94 Documentation/x86_64/boot-options.txt .
96 In addition, the following text indicates that the option:
98 BUGS= Relates to possible processor bugs on the said processor.
99 KNL Is a kernel start-up parameter.
100 BOOT Is a boot loader parameter.
102 Parameters denoted with BOOT are actually interpreted by the boot
103 loader, and have no meaning to the kernel directly.
104 Do not modify the syntax of boot loader parameters without extreme
105 need or coordination with <Documentation/i386/boot.txt>.
107 Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
108 a trailing = on the name of any parameter states that that parameter will
109 be entered as an environment variable, whereas its absence indicates that
110 it will appear as a kernel argument readable via /proc/cmdline by programs
111 running once the system is up.
113 53c7xx= [HW,SCSI] Amiga SCSI controllers
114 See header of drivers/scsi/53c7xx.c.
115 See also Documentation/scsi/ncr53c7xx.txt.
117 acpi= [HW,ACPI] Advanced Configuration and Power Interface
118 Format: { force | off | ht | strict | noirq }
119 force -- enable ACPI if default was off
120 off -- disable ACPI if default was on
121 noirq -- do not use ACPI for IRQ routing
122 ht -- run only enough ACPI to enable Hyper Threading
123 strict -- Be less tolerant of platforms that are not
124 strictly ACPI specification compliant.
126 See also Documentation/pm.txt, pci=noacpi
128 acpi_sleep= [HW,ACPI] Sleep options
129 Format: { s3_bios, s3_mode }
130 See Documentation/power/video.txt
132 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
133 Format: { level | edge | high | low }
135 acpi_irq_balance [HW,ACPI]
136 ACPI will balance active IRQs
139 acpi_irq_nobalance [HW,ACPI]
140 ACPI will not move active IRQs (default)
143 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
145 Format: <irq>,<irq>...
147 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
148 Format: <irq>,<irq>...
150 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
151 Format: To spoof as Windows 98: ="Microsoft Windows"
153 acpi_osi= [HW,ACPI] empty param disables _OSI
155 acpi_serialize [HW,ACPI] force serialization of AML methods
157 acpi_skip_timer_override [HW,ACPI]
158 Recognize and ignore IRQ0/pin2 Interrupt Override.
159 For broken nForce2 BIOS resulting in XT-PIC timer.
161 acpi_dbg_layer= [HW,ACPI]
163 Each bit of the <int> indicates an ACPI debug layer,
164 1: enable, 0: disable. It is useful for boot time
165 debugging. After system has booted up, it can be set
166 via /proc/acpi/debug_layer.
168 acpi_dbg_level= [HW,ACPI]
170 Each bit of the <int> indicates an ACPI debug level,
171 1: enable, 0: disable. It is useful for boot time
172 debugging. After system has booted up, it can be set
173 via /proc/acpi/debug_level.
175 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
177 acpi_generic_hotkey [HW,ACPI]
178 Allow consolidated generic hotkey driver to
179 override platform specific driver.
180 See also Documentation/acpi-hotkey.txt.
182 acpi_pm_good [IA-32,X86-64]
183 Override the pmtimer bug detection: force the kernel
184 to assume that this machine's pmtimer latches its value
185 and always returns good values.
187 enable_timer_pin_1 [i386,x86-64]
188 Enable PIN 1 of APIC timer
189 Can be useful to work around chipset bugs
190 (in particular on some ATI chipsets).
191 The kernel tries to set a reasonable default.
193 disable_timer_pin_1 [i386,x86-64]
194 Disable PIN 1 of APIC timer
195 Can be useful to work around chipset bugs.
198 Format: <io>,<irq>,<dma>,<dma2>
199 See also Documentation/sound/oss/AD1816.
202 Format: <io>,<irq>,<dma>,<dma2>,<type>
208 See header of drivers/scsi/advansys.c.
210 advwdt= [HW,WDT] Advantech WDT
211 Format: <iostart>,<iostop>
213 aedsp16= [HW,OSS] Audio Excel DSP 16
214 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
215 See also header of sound/oss/aedsp16.c.
218 See Documentation/scsi/aha152x.txt.
221 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
224 See Documentation/scsi/aic7xxx.txt.
227 See Documentation/scsi/aic79xx.txt.
229 amijoy.map= [HW,JOY] Amiga joystick support
230 Map of devices attached to JOY0DAT and JOY1DAT
232 See also Documentation/kernel/input/joystick.txt
234 analog.map= [HW,JOY] Analog joystick and gamepad support
235 Specifies type or capabilities of an analog joystick
236 connected to one of 16 gameports
237 Format: <type1>,<type2>,..<type16>
240 Power management functions (SPARCstation-4/5 + deriv.)
242 Disable APC CPU standby support. SPARCstation-Fox does
243 not play well with APC CPU idle - disable it if you have
244 APC and your system crashes randomly.
246 apic= [APIC,i386] Change the output verbosity whilst booting
247 Format: { quiet (default) | verbose | debug }
248 Change the amount of debugging information output
249 when initialising the APIC and IO-APIC components.
251 apm= [APM] Advanced Power Management
252 See header of arch/i386/kernel/apm.c.
257 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
258 Format: <io>,<irq>,<nodeID>
262 atarimouse= [HW,MOUSE] Atari Mouse
264 atascsi= [HW,SCSI] Atari SCSI
266 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
267 EzKey and similar keyboards
269 atkbd.reset= [HW] Reset keyboard during initialization
271 atkbd.set= [HW] Select keyboard code set
272 Format: <int> (2 = AT (default), 3 = PS/2)
274 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
277 atkbd.softraw= [HW] Choose between synthetic and real raw mode
278 Format: <bool> (0 = real, 1 = synthetic (default))
280 atkbd.softrepeat= [HW]
281 Use software keyboard repeat
285 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
286 Format: <io>,<memsize>,<isapnp>
288 aztcd= [HW,CD] Aztech CD268 CDROM driver
289 Format: <io>,0x79 (?)
291 baycom_epp= [HW,AX25]
294 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
296 See header of drivers/net/hamradio/baycom_par.c.
298 baycom_ser_fdx= [HW,AX25]
299 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
300 Format: <io>,<irq>,<mode>[,<baud>]
301 See header of drivers/net/hamradio/baycom_ser_fdx.c.
303 baycom_ser_hdx= [HW,AX25]
304 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
305 Format: <io>,<irq>,<mode>
306 See header of drivers/net/hamradio/baycom_ser_hdx.c.
308 blkmtd_device= [HW,MTD]
314 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
315 bttv.radio= Most important insmod options are available as
317 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
318 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
321 See drivers/scsi/BusLogic.c, comment before function
322 BusLogic_ParseDriverOptions().
324 c101= [NET] Moxa C101 synchronous serial card
326 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
327 Sometimes CPU hardware bugs make them report the cache
328 size incorrectly. The kernel will attempt work arounds
329 to fix known problems, but for some CPUs it is not
330 possible to determine what the correct size should be.
331 This option provides an override for these situations.
334 Format: <io>,<irq>[,PAS]
335 See header of drivers/cdrom/cdu31a.c.
337 chandev= [HW,NET] Generic channel device initialisation
339 checkreqprot [SELINUX] Set initial checkreqprot flag value.
340 Format: { "0" | "1" }
341 See security/selinux/Kconfig help text.
342 0 -- check protection applied by kernel (includes
343 any implied execute protection).
344 1 -- check protection requested by application.
345 Default value is set via a kernel config option.
346 Value can be changed at runtime via
347 /selinux/checkreqprot.
349 clock= [BUGS=IA-32, HW] gettimeofday clocksource override.
351 Forces specified clocksource (if avaliable) to be used
352 when calculating gettimeofday(). If specified
353 clocksource is not avalible, it defaults to PIT.
354 Format: { pit | tsc | cyclone | pmtmr }
358 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
359 over the 8254 in addition to over the IO-APIC. The
360 kernel tries to set a sensible default.
362 hpet= [IA-32,HPET] option to disable HPET and use PIT.
366 Format: { auto | [<io>,][<irq>] }
368 com20020= [HW,NET] ARCnet - COM20020 chipset
370 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
372 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
376 ARCnet - COM90xx chipset (memory-mapped buffers)
377 Format: <io>[,<irq>[,<memstart>]]
379 condev= [HW,S390] console device
382 console= [KNL] Output console device and options.
384 tty<n> Use the virtual console device <n>.
388 Use the specified serial port. The options are of
389 the form "bbbbpnf", where "bbbb" is the baud rate,
390 "p" is parity ("n", "o", or "e"), "n" is number of
391 bits, and "f" is flow control ("r" for RTS or
392 omit it). Default is "9600n8".
394 See Documentation/serial-console.txt for more
396 Documentation/networking/netconsole.txt for an
399 uart,io,<addr>[,options]
400 uart,mmio,<addr>[,options]
401 Start an early, polled-mode console on the 8250/16550
402 UART at the specified I/O port or MMIO address,
403 switching to the matching ttyS device later. The
404 options are the same as for ttyS, above.
406 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
408 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
411 Format: { parport<nr> | auto | none }
413 crashkernel=nn[KMG]@ss[KMG]
414 [KNL] Reserve a chunk of physical memory to
415 hold a kernel to switch to with kexec on panic.
418 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
423 cs89x0_media= [HW,NET]
424 Format: { rj45 | aui | bnc }
426 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
429 See header of drivers/s390/block/dasd_devmap.c.
431 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
432 (one device per port)
433 Format: <port#>,<type>
434 See also Documentation/input/joystick-parport.txt
436 debug [KNL] Enable kernel debugging (events log level).
439 [KNL] verbose self-tests
441 Print debugging info while doing the locking API
443 We default to 0 (no extra messages), setting it to
444 1 will print _a lot_ more information - normally
445 only useful to kernel developers.
448 Format: <area>[,<node>]
449 See also Documentation/networking/decnet.txt.
451 delayacct [KNL] Enable per-task delay accounting
454 Set number of hash buckets for dentry cache.
457 IO parameters + enable/disable command.
459 digiepca= [HW,SERIAL]
460 See drivers/char/README.epca and
461 Documentation/digiepca.txt.
463 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
465 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
467 dmasound= [HW,OSS] Sound subsystem buffers
473 earlyprintk= [IA-32,X86-64]
475 earlyprintk=serial[,ttySn[,baudrate]]
477 Append ",keep" to not disable it when the real console
480 Only vga or serial at a time, not both.
482 Currently only ttyS0 and ttyS1 are supported.
484 Interaction with the standard serial driver is not
487 The VGA output is eventually overwritten by the real
492 ec_intr= [HW,ACPI] ACPI Embedded Controller interrupt mode
495 non-0: interrupt mode (default)
502 Format: {"of[f]" | "sk[ipmbr]"}
503 See comment in arch/i386/boot/edd.S
506 Format: <id>,<membase>,<irq>
508 eisa_irq_edge= [PARISC,HW]
509 See header of drivers/parisc/eisa.c.
512 See comment before function elanfreq_setup() in
513 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
516 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
517 See Documentation/block/as-iosched.txt and
518 Documentation/block/deadline-iosched.txt for details.
520 elfcorehdr= [IA-32, X86_64]
521 Specifies physical address of start of kernel core
522 image elf header. Generally kexec loader will
523 pass this option to capture kernel.
524 See Documentation/kdump/kdump.txt for details.
526 enforcing [SELINUX] Set initial enforcing status.
528 See security/selinux/Kconfig help text.
529 0 -- permissive (log only, no denials).
530 1 -- enforcing (deny and log).
532 Value can be changed at runtime via /selinux/enforce.
535 Format: <lineout>[,<micbias>]
536 See also header of sound/oss/es1370.c.
539 Format: <spdif>,[<nomix>,[<amplifier>]]
540 See also header of sound/oss/es1371.c.
542 ether= [HW,NET] Ethernet cards parameters
543 This option is obsoleted by the "netdev=" option, which
544 has equivalent usage. See its documentation for details.
546 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
550 See header of drivers/scsi/fd_mcs.c.
553 See header of drivers/scsi/fdomain.c.
556 See Documentation/floppy.txt.
558 ftape= [HW] Floppy Tape subsystem debugging options.
559 See Documentation/ftape.txt.
562 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
563 support via parallel port (up to 5 devices per port)
564 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
565 See also Documentation/input/joystick-parport.txt
570 See header of drivers/scsi/gdth.c.
572 gpt [EFI] Forces disk with valid GPT signature but
573 invalid Protective MBR to be treated as GPT.
578 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
581 Format: <io>,<irq>,<dma>,<dma16>
585 hashdist= [KNL,NUMA] Large hashes allocated during boot
586 are distributed across NUMA nodes. Defaults on
587 for IA-64, off otherwise.
588 Format: 0 | 1 (for off | on)
590 hcl= [IA-64] SGI's Hardware Graph compatibility layer
592 hd= [EIDE] (E)IDE hard drive subsystem geometry
593 Format: <cyl>,<head>,<sect>
595 hd?= [HW] (E)IDE subsystem
596 hd?lun= See Documentation/ide.txt.
598 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
599 size of <nn>. This works even on boxes that have no
600 highmem otherwise. This also works to reduce highmem
601 size on bigger boxes.
604 See Documentation/isdn/README.HiSax.
606 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
608 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
610 i8042.direct [HW] Put keyboard port into non-translated mode
611 i8042.dumbkbd [HW] Pretend that controlled can only read data from
612 keyboard and can not control its state
613 (Don't attempt to blink the leds)
614 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
615 i8042.nokbd [HW] Don't check/create keyboard port
616 i8042.nomux [HW] Don't check presence of an active multiplexing
618 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
621 [HW] Frequency with which keyboard LEDs should blink
622 when kernel panics (default is 0.5 sec)
623 i8042.reset [HW] Reset the controller during init and cleanup
624 i8042.unlock [HW] Unlock (ignore) the keylock
628 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
629 indicates that the driver is running on unsupported
631 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
632 does not match list of supported models.
634 [HW] Report power status in /proc/i8k
635 (disabled by default)
636 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
639 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
640 See Documentation/mca.txt.
643 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
645 ide= [HW] (E)IDE subsystem
646 Format: ide=nodma or ide=doubler or ide=reverse
647 See Documentation/ide.txt.
649 ide?= [HW] (E)IDE subsystem
650 Format: ide?=noprobe or chipset specific parameters.
651 See Documentation/ide.txt.
653 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
654 See Documentation/ide.txt.
657 Format: idle=poll or idle=halt
660 Set number of hash buckets for inode cache.
663 See header of drivers/scsi/in2000.c.
667 Run specified binary instead of /sbin/init as init
670 initcall_debug [KNL] Trace initcalls as they are executed. Useful
671 for working out where the kernel is dying during
674 initrd= [BOOT] Specify the location of the initial ramdisk
676 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
679 combined_mode= [HW] control which driver uses IDE ports in combined
680 mode: legacy IDE driver, libata, or both
681 (in the libata case, libata.atapi_enabled=1 may be
682 useful as well). Note that using the ide or libata
683 options may affect your device naming (e.g. by
684 changing hdc to sdb).
685 Format: combined (default), ide, or libata
689 io7= [HW] IO7 for Marvel based alpha systems
690 See comment before marvel_specify_io7 in
691 arch/alpha/kernel/core_marvel.c.
694 See Documentation/nfsroot.txt.
696 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
697 See comment before ip2_setup() in drivers/char/ip2.c.
699 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
700 See header of drivers/scsi/ips.c.
703 When an interrupt is not handled search all handlers
704 for it. Intended to get systems with badly broken
708 When an interrupt is not handled search all handlers
709 for it. Also check all handlers each timer
710 interrupt. Intended to get systems with badly broken
714 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
716 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
717 Format: <cpu number>,...,<cpu number>
718 This option can be used to specify one or more CPUs
719 to isolate from the general SMP balancing and scheduling
720 algorithms. The only way to move a process onto or off
721 an "isolated" CPU is via the CPU affinity syscalls.
722 <cpu number> begins at 0 and the maximum value is
723 "number of CPUs in system - 1".
725 This option is the preferred way to isolate CPUs. The
726 alternative -- manually setting the CPU mask of all
727 tasks in the system -- can cause problems and
728 suboptimal load balancer performance.
731 Format: <io>,<irq>,<dma>,<setup>
735 js= [HW,JOY] Analog joystick
736 See Documentation/input/joystick.txt.
740 kstack=N [IA-32,X86-64] Print N words from the kernel stack
745 lapic [IA-32,APIC] Enable the local APIC even if BIOS
748 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
749 Format: addr:<io>,irq:<irq>
751 llsc*= [IA64] See function print_params() in
752 arch/ia64/sn/kernel/llsc4.c.
754 load_ramdisk= [RAM] List of ramdisks to load from floppy
755 See Documentation/ramdisk.txt.
757 lockd.nlm_grace_period=P [NFS] Assign grace period.
760 lockd.nlm_tcpport=N [NFS] Assign TCP port.
763 lockd.nlm_timeout=T [NFS] Assign timeout value.
766 lockd.nlm_udpport=M [NFS] Assign UDP port.
769 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
772 loglevel= All Kernel Messages with a loglevel smaller than the
773 console loglevel will be printed to the console. It can
774 also be changed with klogd or other programs. The
775 loglevels are defined as follows:
777 0 (KERN_EMERG) system is unusable
778 1 (KERN_ALERT) action must be taken immediately
779 2 (KERN_CRIT) critical conditions
780 3 (KERN_ERR) error conditions
781 4 (KERN_WARNING) warning conditions
782 5 (KERN_NOTICE) normal but significant condition
783 6 (KERN_INFO) informational
784 7 (KERN_DEBUG) debug-level messages
786 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
787 Format: { n | nk | nM }
788 n must be a power of two. The default size
789 is set in the kernel config file.
791 lp=0 [LP] Specify parallel ports to use, e.g,
792 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
793 lp=reset first parallel port). 'lp=0' disables the
794 lp=auto printer driver. 'lp=reset' (which can be
795 specified in addition to the ports) causes
796 attached printers to be reset. Using
797 lp=port1,port2,... specifies the parallel ports
798 to associate lp devices with, starting with
799 lp0. A port specification may be 'none' to skip
800 that lp device, or a parport name such as
801 'parport0'. Specifying 'lp=auto' instead of a
802 port specification list means that device IDs
803 from each port should be examined, to see if
804 an IEEE 1284-compliant printer is attached; if
805 so, the driver will manage that printer.
806 See also header of drivers/char/lp.c.
809 Sets loops_per_jiffy to given constant, thus avoiding
810 time-consuming boot-time autodetection (up to 250 ms per
811 CPU). 0 enables autodetection (default). To determine
812 the correct value for your kernel, boot with normal
813 autodetection and see what value is printed. Note that
814 on SMP systems the preset will be applied to all CPUs,
815 which is likely to cause problems if your CPUs need
816 significantly divergent settings. An incorrect value
817 will cause delays in the kernel to be wrong, leading to
818 unpredictable I/O errors and other breakage. Although
819 unlikely, in the extreme case this might damage your
823 Format: <io>,<irq>,<dma>
825 mac5380= [HW,SCSI] Format:
826 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
828 mac53c9x= [HW,SCSI] Format:
829 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
831 machvec= [IA64] Force the use of a particular machine-vector
832 (machvec) in a generic kernel.
833 Example: machvec=hpzx1_swiotlb
835 mad16= [HW,OSS] Format:
836 <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
841 max_loop= [LOOP] Maximum number of loopback devices that can
845 maxcpus= [SMP] Maximum number of processors that an SMP kernel
848 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
849 equal to this physical address is ignored.
851 max_luns= [SCSI] Maximum number of LUNs to probe.
852 Should be between 1 and 2^32-1.
855 [SCSI] Maximum number of LUNs received.
856 Should be between 1 and 16384.
858 mca-pentium [BUGS=IA-32]
863 Format: <port>,<irq>,<mitsumi_bug_93_wait>
867 mce [IA-32] Machine Check Exception
869 md= [HW] RAID subsystems devices and level
870 See Documentation/md.txt.
873 Format: <first>,<last>
874 Specifies range of consoles to be captured by the MDA.
876 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
877 Amount of memory to be used when the kernel is not able
878 to see the whole system memory or for test.
879 [IA-32] Use together with memmap= to avoid physical
880 address space collisions. Without memmap= PCI devices
881 could be placed at addresses belonging to unused RAM.
883 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
886 memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact
887 E820 memory map, as specified by the user.
888 Such memmap=exactmap lines can be constructed based on
889 BIOS output or other requirements. See the memmap=nn@ss
892 memmap=nn[KMG]@ss[KMG]
893 [KNL] Force usage of a specific region of memory
894 Region of memory to be used, from ss to ss+nn.
896 memmap=nn[KMG]#ss[KMG]
897 [KNL,ACPI] Mark specific memory as ACPI data.
898 Region of memory to be used, from ss to ss+nn.
900 memmap=nn[KMG]$ss[KMG]
901 [KNL,ACPI] Mark specific memory as reserved.
902 Region of memory to be used, from ss to ss+nn.
904 meye.*= [HW] Set MotionEye Camera parameters
905 See Documentation/video4linux/meye.txt.
910 [KNL,SMP] debug: override scheduler migration costs
911 Format: <level-1-usecs>,<level-2-usecs>,...
912 This debugging option can be used to override the
913 default scheduler migration cost matrix. The numbers
914 are indexed by 'CPU domain distance'.
915 E.g. migration_cost=1000,2000,3000 on an SMT NUMA
916 box will set up an intra-core migration cost of
917 1 msec, an inter-core migration cost of 2 msecs,
918 and an inter-node migration cost of 3 msecs.
920 WARNING: using the wrong values here can break
921 scheduler performance, so it's only for scheduler
922 development purposes, not production environments.
925 [KNL,SMP] migration cost auto-detect verbosity
927 If a system's migration matrix reported at bootup
928 seems erroneous then this option can be used to
929 increase verbosity of the detection process.
930 We default to 0 (no extra messages), 1 will print
931 some more information, and 2 will be really
932 verbose (probably only useful if you also have a
933 serial console attached to the system).
936 [KNL,SMP] multiply/divide migration costs by a factor
938 This debug option can be used to proportionally
939 increase or decrease the auto-detected migration
940 costs for all entries of the migration matrix.
941 E.g. migration_factor=150 will increase migration
942 costs by 50%. (and thus the scheduler will be less
943 eager migrating cache-hot tasks)
944 migration_factor=80 will decrease migration costs
945 by 20%. (thus the scheduler will be more eager to
948 WARNING: using the wrong values here can break
949 scheduler performance, so it's only for scheduler
950 development purposes, not production environments.
953 [MOUSE] Maximum time between finger touching and
954 leaving touchpad surface for touch to be considered
955 a tap and be reported as a left button click (for
956 touchpads working in absolute mode only).
958 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
959 reporting absolute coordinates, such as tablets
960 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
961 reporting absolute coordinates, such as tablets
967 Format: <name>,<region-number>,<size>,<offset>
969 MTD_Region= [MTD] Format:
970 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
973 See drivers/mtd/cmdline.c.
975 mtouchusb.raw_coordinates=
976 [HW] Make the MicroTouch USB driver use raw coordinates
977 ('y', default) or cooked coordinates ('n')
979 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
982 See header of drivers/scsi/NCR_D700.c.
988 ncr53c400a= [HW,SCSI]
990 ncr53c406a= [HW,SCSI]
994 netdev= [NET] Network devices parameters
995 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
996 Note that mem_start is often overloaded to mean
997 something different and driver-specific.
998 This usage is only documented in each driver source
1002 See Documentation/nfsroot.txt.
1004 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
1005 See Documentation/nfsroot.txt.
1007 nfs.callback_tcpport=
1008 [NFS] set the TCP port on which the NFSv4 callback
1009 channel should listen.
1011 nfs.idmap_cache_timeout=
1012 [NFS] set the maximum lifetime for idmapper cache
1015 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
1017 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
1018 emulation library even if a 387 maths coprocessor
1023 noapic [SMP,APIC] Tells the kernel to not make use of any
1024 IOAPICs that may be present in the system.
1026 noasync [HW,M68K] Disables async and sync negotiation for
1029 nobats [PPC] Do not use BATs for mapping kernel lowmem
1030 on "Classic" PPC cores.
1034 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1038 noexec [IA-32,X86-64]
1039 noexec=on: enable non-executable mappings (default)
1040 noexec=off: disable nn-executable mappings
1042 nofxsr [BUGS=IA-32] Disables x86 floating point extended
1043 register save and restore. The kernel will only save
1044 legacy floating-point registers on task switch.
1048 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
1049 instruction doesn't work correctly and not to
1052 nohalt [IA-64] Tells the kernel not to use the power saving
1053 function PAL_HALT_LIGHT when idle. This increases
1054 power-consumption. On the positive side, it reduces
1055 interrupt wake-up latency, which may improve performance
1056 in certain environments such as networked servers or
1059 noirqdebug [IA-32] Disables the code which attempts to detect and
1060 disable unhandled interrupt sources.
1062 noisapnp [ISAPNP] Disables ISA PnP code.
1064 noinitrd [RAM] Tells the kernel not to load any configured
1069 nolapic [IA-32,APIC] Do not enable or use the local APIC.
1071 noltlbs [PPC] Do not use large page/tlb entries for kernel
1072 lowmem mapping on PPC40x.
1074 nomca [IA-64] Disable machine check abort handling
1076 nomce [IA-32] Machine Check Exception
1078 noresidual [PPC] Don't use residual data on PReP machines.
1080 noresume [SWSUSP] Disables resume and restores original swap
1083 no-scroll [VGA] Disables scrollback.
1084 This is required for the Braillex ib80-piezo Braille
1085 reader made by F.H. Papenmeier (Germany).
1089 nosep [BUGS=IA-32] Disables x86 SYSENTER/SYSEXIT support.
1091 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
1093 nosync [HW,M68K] Disables sync negotiation for all devices.
1095 notsc [BUGS=IA-32] Disable Time Stamp Counter
1097 nousb [USB] Disable the USB subsystem
1101 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1107 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
1109 opl3sa2= [HW,OSS] Format:
1110 <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
1112 oprofile.timer= [HW]
1113 Use timer interrupt instead of performance counters
1118 osst= [HW,SCSI] SCSI Tape Driver
1119 Format: <buffer_size>,<write_threshold>
1120 See also Documentation/scsi/st.txt.
1122 panic= [KNL] Kernel behaviour on panic
1125 parkbd.port= [HW] Parallel port number the keyboard adapter is
1126 connected to, default is 0.
1128 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1129 0 for XT, 1 for AT (default is AT).
1132 parport= [HW,PPT] Specify parallel ports. 0 disables.
1133 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1134 Use 'auto' to force the driver to use any
1135 IRQ/DMA settings detected (the default is to
1136 ignore detected IRQ/DMA settings because of
1137 possible conflicts). You can specify the base
1138 address, IRQ, and DMA settings; IRQ and DMA
1139 should be numbers, or 'auto' (for using detected
1140 settings on that particular port), or 'nofifo'
1141 (to avoid using a FIFO even if it is detected).
1142 Parallel ports are assigned in the order they
1143 are specified on the command line, starting
1146 parport_init_mode= [HW,PPT]
1147 Configure VIA parallel port to operate in
1148 a specific mode. This is necessary on Pegasos
1149 computer where firmware has no options for setting
1150 up parallel port mode and sets it to spp.
1151 Currently this function knows 686a and 8231 chips.
1152 Format: [spp|ps2|epp|ecp|ecpepp]
1154 pas2= [HW,OSS] Format:
1155 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1158 See header of drivers/scsi/pas16.c.
1161 Halt all CPUs after the first oops has been printed for
1162 the specified number of seconds. This is to be used if
1163 your oopses keep scrolling off the screen.
1168 See header of drivers/block/paride/pcd.c.
1169 See also Documentation/paride.txt.
1171 pci=option[,option...] [PCI] various PCI subsystem options:
1172 off [IA-32] don't probe for the PCI bus
1173 bios [IA-32] force use of PCI BIOS, don't access
1174 the hardware directly. Use this if your machine
1175 has a non-standard PCI host bridge.
1176 nobios [IA-32] disallow use of PCI BIOS, only direct
1177 hardware access methods are allowed. Use this
1178 if you experience crashes upon bootup and you
1179 suspect they are caused by the BIOS.
1180 conf1 [IA-32] Force use of PCI Configuration
1182 conf2 [IA-32] Force use of PCI Configuration
1184 nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
1186 nomsi [MSI] If the PCI_MSI kernel config parameter is
1187 enabled, this kernel boot option can be used to
1188 disable the use of MSI interrupts system-wide.
1189 nosort [IA-32] Don't sort PCI devices according to
1190 order given by the PCI BIOS. This sorting is
1191 done to get a device order compatible with
1193 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1194 routing table. These calls are known to be buggy
1195 on several machines and they hang the machine
1196 when used, but on other computers it's the only
1197 way to get the interrupt routing table. Try
1198 this option if the kernel is unable to allocate
1199 IRQs or discover secondary PCI buses on your
1201 rom [IA-32] Assign address space to expansion ROMs.
1202 Use with caution as certain devices share
1203 address decoders between ROMs and other
1205 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be
1206 assigned automatically to PCI devices. You can
1207 make the kernel exclude IRQs of your ISA cards
1209 pirqaddr=0xAAAAA [IA-32] Specify the physical address
1210 of the PIRQ table (normally generated
1211 by the BIOS) if it is outside the
1212 F0000h-100000h range.
1213 lastbus=N [IA-32] Scan all buses thru bus #N. Can be
1214 useful if the kernel is unable to find your
1215 secondary buses and you want to tell it
1216 explicitly which ones they are.
1217 assign-busses [IA-32] Always assign all PCI bus
1218 numbers ourselves, overriding
1219 whatever the firmware may have done.
1220 usepirqmask [IA-32] Honor the possible IRQ mask stored
1221 in the BIOS $PIR table. This is needed on
1222 some systems with broken BIOSes, notably
1223 some HP Pavilion N5400 and Omnibook XE3
1224 notebooks. This will have no effect if ACPI
1225 IRQ routing is enabled.
1226 noacpi [IA-32] Do not use ACPI for IRQ routing
1227 or for PCI scanning.
1228 routeirq Do IRQ routing for all PCI devices.
1229 This is normally done in pci_enable_device(),
1230 so this option is a temporary workaround
1231 for broken drivers that don't call it.
1232 firmware [ARM] Do not re-enumerate the bus but instead
1233 just use the configuration from the
1234 bootloader. This is currently used on
1235 IXP2000 systems where the bus has to be
1236 configured a certain way for adjunct CPUs.
1238 pcmv= [HW,PCMCIA] BadgePAD 4
1241 See Documentation/paride.txt.
1243 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1246 See arch/parisc/kernel/pdc_chassis.c
1249 See Documentation/paride.txt.
1252 See Documentation/paride.txt.
1254 pirq= [SMP,APIC] Manual mp-table setup
1255 See Documentation/i386/IO-APIC.txt.
1257 plip= [PPT,NET] Parallel port network link
1258 Format: { parport<nr> | timid | 0 }
1259 See also Documentation/parport.txt.
1265 { on | off | curr | res | no-curr | no-res }
1268 [ISAPNP] Exclude IRQs for the autoconfiguration
1271 [ISAPNP] Exclude DMAs for the autoconfiguration
1273 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1274 Ranges are in pairs (I/O port base and size).
1277 [ISAPNP] Exclude memory regions for the
1279 Ranges are in pairs (memory base and size).
1281 profile= [KNL] Enable kernel profiling via /proc/profile
1282 Format: [schedule,]<number>
1283 Param: "schedule" - profile schedule points.
1284 Param: <number> - step/bucket size as a power of 2 for
1285 statistical time based profiling.
1287 processor.max_cstate= [HW,ACPI]
1288 Limit processor to maximum C-state
1289 max_cstate=9 overrides any DMI blacklist limit.
1291 processor.nocst [HW,ACPI]
1292 Ignore the _CST method to determine C-states,
1293 instead using the legacy FADT method
1295 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1297 See Documentation/ramdisk.txt.
1299 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1300 probe for; one of (bare|imps|exps|lifebook|any).
1301 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1303 psmouse.resetafter= [HW,MOUSE]
1304 Try to reset the device after so many bad packets
1307 [HW,MOUSE] Set desired mouse resolution, in dpi.
1308 psmouse.smartscroll=
1309 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
1310 0 = disabled, 1 = enabled (default).
1312 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1314 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1317 See Documentation/paride.txt.
1319 quiet= [KNL] Disable log messages
1324 See Documentation/md.txt.
1326 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1327 See Documentation/ramdisk.txt.
1329 ramdisk_blocksize= [RAM]
1330 See Documentation/ramdisk.txt.
1332 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1333 New name for the ramdisk parameter.
1334 See Documentation/ramdisk.txt.
1336 rcu.blimit= [KNL,BOOT] Set maximum number of finished
1337 RCU callbacks to process in one batch.
1339 rcu.qhimark= [KNL,BOOT] Set threshold of queued
1340 RCU callbacks over which batch limiting is disabled.
1342 rcu.qlowmark= [KNL,BOOT] Set threshold of queued
1343 RCU callbacks below which batch limiting is re-enabled.
1345 rcu.rsinterval= [KNL,BOOT,SMP] Set the number of additional
1346 RCU callbacks to queued before forcing reschedule
1351 Run specified binary instead of /init from the ramdisk,
1352 used for early userspace startup. See initrd.
1354 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1355 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1356 See arch/*/kernel/reboot.c.
1358 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1361 Specify the partition device for software suspend
1363 rhash_entries= [KNL,NET]
1364 Set number of hash buckets for route cache
1366 riscom8= [HW,SERIAL]
1367 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1369 ro [KNL] Mount root device read-only on boot
1371 root= [KNL] Root filesystem
1373 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1374 mount the root filesystem
1376 rootflags= [KNL] Set root filesystem mount option string
1378 rootfstype= [KNL] Set root filesystem type
1380 rw [KNL] Mount root device read-write on boot
1382 S [KNL] Run init in single mode
1385 See drivers/net/irda/sa1100_ir.c.
1388 Format: <io>,<irq>,<dma>,<dma2>
1390 sbni= [NET] Granch SBNI12 leased line adapter
1392 sbpcd= [HW,CD] Soundblaster CD adapter
1394 See a comment before function sbpcd_setup() in
1395 drivers/cdrom/sbpcd.c.
1397 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1398 Format: <io>[,<timeout>[,<isapnp>]]
1400 scsi_debug_*= [SCSI]
1401 See drivers/scsi/scsi_debug.c.
1403 scsi_default_dev_flags=
1404 [SCSI] SCSI default device flags
1407 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1408 Format: <vendor>:<model>:<flags>
1409 (flags are integer value)
1411 scsi_logging= [SCSI]
1413 selinux [SELINUX] Disable or enable SELinux at boot time.
1414 Format: { "0" | "1" }
1415 See security/selinux/Kconfig help text.
1418 Default value is set via kernel config option.
1419 If enabled at boot time, /selinux/disable can be used
1420 later to disable prior to initial policy load.
1422 selinux_compat_net =
1423 [SELINUX] Set initial selinux_compat_net flag value.
1424 Format: { "0" | "1" }
1425 0 -- use new secmark-based packet controls
1426 1 -- use legacy packet controls
1427 Default value is 0 (preferred).
1428 Value can be changed at runtime via
1429 /selinux/compat_net.
1431 serialnumber [BUGS=IA-32]
1433 sg_def_reserved_size= [SCSI]
1436 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1439 Maximal number of shapers.
1442 See header of drivers/scsi/sim710.c.
1448 Format: <io>,<irq>,<dma>
1449 See header of drivers/cdrom/sjcd.c.
1454 Format: <io1>[,<io2>[,...,<io8>]]
1456 snd-ad1816a= [HW,ALSA]
1458 snd-ad1848= [HW,ALSA]
1460 snd-ali5451= [HW,ALSA]
1462 snd-als100= [HW,ALSA]
1464 snd-als4000= [HW,ALSA]
1466 snd-azt2320= [HW,ALSA]
1468 snd-cmi8330= [HW,ALSA]
1470 snd-cmipci= [HW,ALSA]
1472 snd-cs4231= [HW,ALSA]
1474 snd-cs4232= [HW,ALSA]
1476 snd-cs4236= [HW,ALSA]
1478 snd-cs4281= [HW,ALSA]
1480 snd-cs46xx= [HW,ALSA]
1482 snd-dt019x= [HW,ALSA]
1484 snd-dummy= [HW,ALSA]
1486 snd-emu10k1= [HW,ALSA]
1488 snd-ens1370= [HW,ALSA]
1490 snd-ens1371= [HW,ALSA]
1492 snd-es968= [HW,ALSA]
1494 snd-es1688= [HW,ALSA]
1496 snd-es18xx= [HW,ALSA]
1498 snd-es1938= [HW,ALSA]
1500 snd-es1968= [HW,ALSA]
1502 snd-fm801= [HW,ALSA]
1504 snd-gusclassic= [HW,ALSA]
1506 snd-gusextreme= [HW,ALSA]
1508 snd-gusmax= [HW,ALSA]
1512 snd-ice1712= [HW,ALSA]
1514 snd-intel8x0= [HW,ALSA]
1516 snd-interwave= [HW,ALSA]
1521 snd-korg1212= [HW,ALSA]
1523 snd-maestro3= [HW,ALSA]
1525 snd-mpu401= [HW,ALSA]
1527 snd-mtpav= [HW,ALSA]
1529 snd-nm256= [HW,ALSA]
1531 snd-opl3sa2= [HW,ALSA]
1539 snd-opti93x= [HW,ALSA]
1543 snd-rme32= [HW,ALSA]
1545 snd-rme96= [HW,ALSA]
1547 snd-rme9652= [HW,ALSA]
1553 snd-sbawe= [HW,ALSA]
1555 snd-serial= [HW,ALSA]
1557 snd-sgalaxy= [HW,ALSA]
1559 snd-sonicvibes= [HW,ALSA]
1564 snd-sun-cs4231= [HW,ALSA]
1566 snd-trident= [HW,ALSA]
1568 snd-usb-audio= [HW,ALSA,USB]
1570 snd-via82xx= [HW,ALSA]
1572 snd-virmidi= [HW,ALSA]
1574 snd-wavefront= [HW,ALSA]
1576 snd-ymfpci= [HW,ALSA]
1578 sonicvibes= [HW,OSS]
1582 Format: <io>[,<irq>]
1584 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1585 See Documentation/sonypi.txt
1587 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1588 See Documentation/specialix.txt.
1590 spia_io_base= [HW,MTD]
1596 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1598 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1599 See Documentation/scsi/st.txt.
1602 See header of drivers/scsi/seagate.c.
1606 Set the STI (builtin display/keyboard on the HP-PARISC
1607 machines) console (graphic card) which should be used
1608 as the initial boot-console.
1609 See also comment in drivers/video/console/sticore.c.
1612 See comment in drivers/video/console/sticore.c.
1615 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1617 swiotlb= [IA-64] Number of I/O TLB slabs
1621 sym53c416= [HW,SCSI]
1622 See header of drivers/scsi/sym53c416.c.
1625 See header of drivers/scsi/t128.c.
1629 thash_entries= [KNL,NET]
1630 Set number of hash buckets for TCP connection
1632 time Show timing data prefixed to each printk message line
1634 clocksource= [GENERIC_TIME] Override the default clocksource
1635 Override the default clocksource and use the clocksource
1636 with the name specified.
1638 tipar.timeout= [HW,PPT]
1639 Set communications timeout in tenths of a second
1642 tipar.delay= [HW,PPT]
1643 Set inter-bit delay in microseconds (default 10).
1646 See header of drivers/scsi/seagate.c.
1649 See comment before function dc390_setup() in
1650 drivers/scsi/tmscsim.c.
1654 trix= [HW,OSS] MediaTrix AudioTrix Pro
1656 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1658 tsdev.xres= [TS] Horizontal screen resolution.
1659 tsdev.yres= [TS] Vertical screen resolution.
1661 turbografx.map[2|3]= [HW,JOY]
1662 TurboGraFX parallel port interface
1664 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1665 See also Documentation/input/joystick-parport.txt
1667 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1668 See header of drivers/scsi/u14-34f.c.
1677 [USBHID] The interval which mice are to be polled at.
1680 vdso=1: enable VDSO (default)
1681 vdso=0: disable VDSO mapping
1683 video= [FB] Frame buffer configuration
1684 See Documentation/fb/modedb.txt.
1686 vga= [BOOT,IA-32] Select a particular video mode
1687 See Documentation/i386/boot.txt and
1688 Documentation/svga.txt.
1689 Use vga=ask for menu.
1690 This is actually a boot loader parameter; the value is
1691 passed to the kernel using a special protocol.
1693 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
1694 size of <nn>. This can be used to increase the
1695 minimum size (128MB on x86). It can also be used to
1696 decrease the size and leave more room for directly
1699 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
1702 vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
1705 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
1708 waveartist= [HW,OSS]
1709 Format: <io>,<irq>,<dma>,<dma2>
1712 See header of drivers/scsi/wd33c93.c.
1715 See header of drivers/scsi/wd7000.c.
1718 See Documentation/watchdog/watchdog.txt.
1720 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1721 xd_geo= See header of drivers/block/xd.c.
1723 xirc2ps_cs= [NET,PCMCIA]
1725 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1727 norandmaps Don't use address space randomization
1728 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
1731 ______________________________________________________________________
1735 Add documentation for ALSA options.
1736 Add more DRM drivers.