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Linus Torvalds1da177e2005-04-16 15:20:36 -07001February 2003 Kernel Parameters v2.5.59
2 ~~~~~~~~~~~~~~~~~
3
4The 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
7case insensitive manner), and with descriptions where known.
8
9Module parameters for loadable modules are specified only as the
10parameter name with optional '=' and value as appropriate, such as:
11
12 modprobe usbcore blinkenlights=1
13
14Module parameters for modules that are built into the kernel image
15are specified on the kernel command line with the module name plus
16'.' plus parameter name, with '=' and value if appropriate, such as:
17
18 usbcore.blinkenlights=1
19
20The text in square brackets at the beginning of the description state the
21restrictions on the kernel for the said kernel parameter to be valid. The
22restrictions referred to are that the relevant option is valid if:
23
24 ACPI ACPI support is enabled.
25 ALSA ALSA sound support is enabled.
26 APIC APIC support is enabled.
27 APM Advanced Power Management support is enabled.
28 AX25 Appropriate AX.25 support is enabled.
29 CD Appropriate CD support is enabled.
30 DEVFS devfs support is enabled.
31 DRM Direct Rendering Management support is enabled.
32 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
33 EFI EFI Partitioning (GPT) is enabled
34 EIDE EIDE/ATAPI support is enabled.
35 FB The frame buffer device is enabled.
36 HW Appropriate hardware is enabled.
37 IA-32 IA-32 aka i386 architecture is enabled.
38 IA-64 IA-64 architecture is enabled.
39 IOSCHED More than one I/O scheduler is enabled.
40 IP_PNP IP DCHP, BOOTP, or RARP is enabled.
41 ISAPNP ISA PnP code is enabled.
42 ISDN Appropriate ISDN support is enabled.
43 JOY Appropriate joystick support is enabled.
44 LP Printer support is enabled.
45 LOOP Loopback device support is enabled.
46 M68k M68k architecture is enabled.
47 These options have more detailed description inside of
48 Documentation/m68k/kernel-options.txt.
49 MCA MCA bus support is enabled.
50 MDA MDA console support is enabled.
51 MOUSE Appropriate mouse support is enabled.
52 MTD MTD support is enabled.
53 NET Appropriate network support is enabled.
54 NUMA NUMA support is enabled.
55 NFS Appropriate NFS support is enabled.
56 OSS OSS sound support is enabled.
57 PARIDE The ParIDE subsystem is enabled.
58 PARISC The PA-RISC architecture is enabled.
59 PCI PCI bus support is enabled.
60 PCMCIA The PCMCIA subsystem is enabled.
61 PNP Plug & Play support is enabled.
62 PPC PowerPC architecture is enabled.
63 PPT Parallel port support is enabled.
64 PS2 Appropriate PS/2 support is enabled.
65 RAM RAM disk support is enabled.
66 S390 S390 architecture is enabled.
67 SCSI Appropriate SCSI support is enabled.
68 A lot of drivers has their options described inside of
69 Documentation/scsi/.
70 SELINUX SELinux support is enabled.
71 SERIAL Serial support is enabled.
72 SMP The kernel is an SMP kernel.
73 SPARC Sparc architecture is enabled.
74 SWSUSP Software suspension is enabled.
75 TS Appropriate touchscreen support is enabled.
76 USB USB support is enabled.
77 USBHID USB Human Interface Device support is enabled.
78 V4L Video For Linux support is enabled.
79 VGA The VGA console has been enabled.
80 VT Virtual terminal support is enabled.
81 WDT Watchdog support is enabled.
82 XT IBM PC/XT MFM hard disk support is enabled.
83 X86-64 X86-64 architecture is enabled.
84 More X86-64 boot options can be found in
85 Documentation/x86_64/boot-options.txt .
86
87In addition, the following text indicates that the option:
88
89 BUGS= Relates to possible processor bugs on the said processor.
90 KNL Is a kernel start-up parameter.
91 BOOT Is a boot loader parameter.
92
93Parameters denoted with BOOT are actually interpreted by the boot
94loader, and have no meaning to the kernel directly.
95Do not modify the syntax of boot loader parameters without extreme
96need or coordination with <Documentation/i386/boot.txt>.
97
98Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
99a trailing = on the name of any parameter states that that parameter will
100be entered as an environment variable, whereas its absence indicates that
101it will appear as a kernel argument readable via /proc/cmdline by programs
102running once the system is up.
103
104 53c7xx= [HW,SCSI] Amiga SCSI controllers
105 See header of drivers/scsi/53c7xx.c.
106 See also Documentation/scsi/ncr53c7xx.txt.
107
108 acpi= [HW,ACPI] Advanced Configuration and Power Interface
109 Format: { force | off | ht | strict }
110 force -- enable ACPI if default was off
111 off -- disable ACPI if default was on
112 noirq -- do not use ACPI for IRQ routing
113 ht -- run only enough ACPI to enable Hyper Threading
114 strict -- Be less tolerant of platforms that are not
115 strictly ACPI specification compliant.
116
117 See also Documentation/pm.txt, pci=noacpi
118
119 acpi_sleep= [HW,ACPI] Sleep options
120 Format: { s3_bios, s3_mode }
121 See Documentation/power/video.txt
122
123 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
124 Format: { level | edge | high | low }
125
126 acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs
127 default in APIC mode
128
129 acpi_irq_nobalance [HW,ACPI] ACPI will not move active IRQs (default)
130 default in PIC mode
131
132 acpi_irq_pci= [HW,ACPI] If irq_balance, Clear listed IRQs for use by PCI
133 Format: <irq>,<irq>...
134
135 acpi_irq_isa= [HW,ACPI] If irq_balance, Mark listed IRQs used by ISA
136 Format: <irq>,<irq>...
137
138 acpi_osi= [HW,ACPI] empty param disables _OSI
139
140 acpi_serialize [HW,ACPI] force serialization of AML methods
141
142 acpi_skip_timer_override [HW,ACPI]
143 Recognize and ignore IRQ0/pin2 Interrupt Override.
144 For broken nForce2 BIOS resulting in XT-PIC timer.
145
146 acpi_dbg_layer= [HW,ACPI]
147 Format: <int>
148 Each bit of the <int> indicates an acpi debug layer,
149 1: enable, 0: disable. It is useful for boot time
150 debugging. After system has booted up, it can be set
151 via /proc/acpi/debug_layer.
152
153 acpi_dbg_level= [HW,ACPI]
154 Format: <int>
155 Each bit of the <int> indicates an acpi debug level,
156 1: enable, 0: disable. It is useful for boot time
157 debugging. After system has booted up, it can be set
158 via /proc/acpi/debug_level.
159
160 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
161
162 ad1816= [HW,OSS]
163 Format: <io>,<irq>,<dma>,<dma2>
164 See also Documentation/sound/oss/AD1816.
165
166 ad1848= [HW,OSS]
167 Format: <io>,<irq>,<dma>,<dma2>,<type>
168
169 adlib= [HW,OSS]
170 Format: <io>
171
172 advansys= [HW,SCSI]
173 See header of drivers/scsi/advansys.c.
174
175 advwdt= [HW,WDT] Advantech WDT
176 Format: <iostart>,<iostop>
177
178 aedsp16= [HW,OSS] Audio Excel DSP 16
179 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
180 See also header of sound/oss/aedsp16.c.
181
182 aha152x= [HW,SCSI]
183 See Documentation/scsi/aha152x.txt.
184
185 aha1542= [HW,SCSI]
186 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
187
188 aic7xxx= [HW,SCSI]
189 See Documentation/scsi/aic7xxx.txt.
190
191 aic79xx= [HW,SCSI]
192 See Documentation/scsi/aic79xx.txt.
193
194 AM53C974= [HW,SCSI]
195 Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
196 See also header of drivers/scsi/AM53C974.c.
197
198 amijoy.map= [HW,JOY] Amiga joystick support
199 Map of devices attached to JOY0DAT and JOY1DAT
200 Format: <a>,<b>
201 See also Documentation/kernel/input/joystick.txt
202
203 analog.map= [HW,JOY] Analog joystick and gamepad support
204 Specifies type or capabilities of an analog joystick
205 connected to one of 16 gameports
206 Format: <type1>,<type2>,..<type16>
207
208 apc= [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.)
209 Format: noidle
210 Disable APC CPU standby support. SPARCstation-Fox does
211 not play well with APC CPU idle - disable it if you have
212 APC and your system crashes randomly.
213
214 apic= [APIC,i386] Change the output verbosity whilst booting
215 Format: { quiet (default) | verbose | debug }
216 Change the amount of debugging information output
217 when initialising the APIC and IO-APIC components.
218
219 apm= [APM] Advanced Power Management
220 See header of arch/i386/kernel/apm.c.
221
222 applicom= [HW]
223 Format: <mem>,<irq>
224
225 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
226 Format: <io>,<irq>,<nodeID>
227
228 ataflop= [HW,M68k]
229
230 atarimouse= [HW,MOUSE] Atari Mouse
231
232 atascsi= [HW,SCSI] Atari SCSI
233
234 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
235 EzKey and similar keyboards
236
237 atkbd.reset= [HW] Reset keyboard during initialization
238
239 atkbd.set= [HW] Select keyboard code set
240 Format: <int> (2 = AT (default) 3 = PS/2)
241
242 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
243 keyboards
244
245 atkbd.softraw= [HW] Choose between synthetic and real raw mode
246 Format: <bool> (0 = real, 1 = synthetic (default))
247
248 atkbd.softrepeat=
249 [HW] Use software keyboard repeat
250
251 autotest [IA64]
252
253 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
254 Format: <io>,<memsize>,<isapnp>
255
256 aztcd= [HW,CD] Aztech CD268 CDROM driver
257 Format: <io>,0x79 (?)
258
259 baycom_epp= [HW,AX25]
260 Format: <io>,<mode>
261
262 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
263 Format: <io>,<mode>
264 See header of drivers/net/hamradio/baycom_par.c.
265
266 baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode)
267 Format: <io>,<irq>,<mode>[,<baud>]
268 See header of drivers/net/hamradio/baycom_ser_fdx.c.
269
270 baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode)
271 Format: <io>,<irq>,<mode>
272 See header of drivers/net/hamradio/baycom_ser_hdx.c.
273
274 blkmtd_device= [HW,MTD]
275 blkmtd_erasesz=
276 blkmtd_ro=
277 blkmtd_bs=
278 blkmtd_count=
279
280 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
281 bttv.radio= Most important insmod options are available as kernel args too.
282 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
283 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
284
285 BusLogic= [HW,SCSI]
286 See drivers/scsi/BusLogic.c, comment before function
287 BusLogic_ParseDriverOptions().
288
289 c101= [NET] Moxa C101 synchronous serial card
290
291 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
292 Sometimes CPU hardware bugs make them report the cache
293 size incorrectly. The kernel will attempt work arounds
294 to fix known problems, but for some CPUs it is not
295 possible to determine what the correct size should be.
296 This option provides an override for these situations.
297
298 cdu31a= [HW,CD]
299 Format: <io>,<irq>[,PAS]
300 See header of drivers/cdrom/cdu31a.c.
301
302 chandev= [HW,NET] Generic channel device initialisation
303
304 checkreqprot [SELINUX] Set initial checkreqprot flag value.
305 Format: { "0" | "1" }
306 See security/selinux/Kconfig help text.
307 0 -- check protection applied by kernel (includes any implied execute protection).
308 1 -- check protection requested by application.
309 Default value is set via a kernel config option.
310 Value can be changed at runtime via /selinux/checkreqprot.
311
312 clock= [BUGS=IA-32, HW] gettimeofday timesource override.
313 Forces specified timesource (if avaliable) to be used
314 when calculating gettimeofday(). If specicified timesource
315 is not avalible, it defaults to PIT.
316 Format: { pit | tsc | cyclone | pmtmr }
317
318 hpet= [IA-32,HPET] option to disable HPET and use PIT.
319 Format: disable
320
321 cm206= [HW,CD]
322 Format: { auto | [<io>,][<irq>] }
323
324 com20020= [HW,NET] ARCnet - COM20020 chipset
325 Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
326
327 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
328 Format: <io>[,<irq>]
329
330 com90xx= [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers)
331 Format: <io>[,<irq>[,<memstart>]]
332
333 condev= [HW,S390] console device
334 conmode=
335
336 console= [KNL] Output console device and options.
337
338 tty<n> Use the virtual console device <n>.
339
340 ttyS<n>[,options]
341 Use the specified serial port. The options are of
342 the form "bbbbpn", where "bbbb" is the baud rate,
343 "p" is parity ("n", "o", or "e"), and "n" is bits.
344 Default is "9600n8".
345
346 See also Documentation/serial-console.txt.
347
348 uart,io,<addr>[,options]
349 uart,mmio,<addr>[,options]
350 Start an early, polled-mode console on the 8250/16550
351 UART at the specified I/O port or MMIO address,
352 switching to the matching ttyS device later. The
353 options are the same as for ttyS, above.
354
355 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
356 Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
357
358 cpia_pp= [HW,PPT]
359 Format: { parport<nr> | auto | none }
360
361 cs4232= [HW,OSS]
362 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
363
364 cs89x0_dma= [HW,NET]
365 Format: <dma>
366
367 cs89x0_media= [HW,NET]
368 Format: { rj45 | aui | bnc }
369
370 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
371
372 dasd= [HW,NET]
373 See header of drivers/s390/block/dasd_devmap.c.
374
375 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
376 (one device per port)
377 Format: <port#>,<type>
378 See also Documentation/input/joystick-parport.txt
379
380 debug [KNL] Enable kernel debugging (events log level).
381
382 decnet= [HW,NET]
383 Format: <area>[,<node>]
384 See also Documentation/networking/decnet.txt.
385
386 devfs= [DEVFS]
387 See Documentation/filesystems/devfs/boot-options.
388
389 dhash_entries= [KNL]
390 Set number of hash buckets for dentry cache.
391
392 digi= [HW,SERIAL]
393 IO parameters + enable/disable command.
394
395 digiepca= [HW,SERIAL]
396 See drivers/char/README.epca and
397 Documentation/digiepca.txt.
398
399 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
400 support available.
401 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
402
403 dmasound= [HW,OSS] Sound subsystem buffers
404
405 dscc4.setup= [NET]
406
407 dtc3181e= [HW,SCSI]
408
409 earlyprintk= [IA-32, X86-64]
410 earlyprintk=vga
411 earlyprintk=serial[,ttySn[,baudrate]]
412
413 Append ,keep to not disable it when the real console
414 takes over.
415
416 Only vga or serial at a time, not both.
417
418 Currently only ttyS0 and ttyS1 are supported.
419
420 Interaction with the standard serial driver is not
421 very good.
422
423 The VGA output is eventually overwritten by the real
424 console.
425
426 eata= [HW,SCSI]
427
428 eda= [HW,PS2]
429
430 edb= [HW,PS2]
431
432 edd= [EDD]
433 Format: {"of[f]" | "sk[ipmbr]"}
434 See comment in arch/i386/boot/edd.S
435
436 eicon= [HW,ISDN]
437 Format: <id>,<membase>,<irq>
438
439 eisa_irq_edge= [PARISC,HW]
440 See header of drivers/parisc/eisa.c.
441
442 elanfreq= [IA-32]
443 See comment before function elanfreq_setup() in
444 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
445
446 elevator= [IOSCHED]
447 Format: {"as"|"cfq"|"deadline"|"noop"}
448 See Documentation/block/as-iosched.txt
449 and Documentation/block/deadline-iosched.txt for details.
450
451 enforcing [SELINUX] Set initial enforcing status.
452 Format: {"0" | "1"}
453 See security/selinux/Kconfig help text.
454 0 -- permissive (log only, no denials).
455 1 -- enforcing (deny and log).
456 Default value is 0.
457 Value can be changed at runtime via /selinux/enforce.
458
459 es1370= [HW,OSS]
460 Format: <lineout>[,<micbias>]
461 See also header of sound/oss/es1370.c.
462
463 es1371= [HW,OSS]
464 Format: <spdif>,[<nomix>,[<amplifier>]]
465 See also header of sound/oss/es1371.c.
466
467 ether= [HW,NET] Ethernet cards parameters
468 This option is obsoleted by the "netdev=" option, which
469 has equivalent usage. See its documentation for details.
470
471 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
472 Format: <io>[,<irq>]
473
474 fd_mcs= [HW,SCSI]
475 See header of drivers/scsi/fd_mcs.c.
476
477 fdomain= [HW,SCSI]
478 See header of drivers/scsi/fdomain.c.
479
480 floppy= [HW]
481 See Documentation/floppy.txt.
482
483 ftape= [HW] Floppy Tape subsystem debugging options.
484 See Documentation/ftape.txt.
485
486 gamecon.map[2|3]=
487 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
488 support via parallel port (up to 5 devices per port)
489 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
490 See also Documentation/input/joystick-parport.txt
491
492 gamma= [HW,DRM]
493
494 gdth= [HW,SCSI]
495 See header of drivers/scsi/gdth.c.
496
497 gpt [EFI] Forces disk with valid GPT signature but
498 invalid Protective MBR to be treated as GPT.
499
500 gscd= [HW,CD]
501 Format: <io>
502
503 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
504
505 gus= [HW,OSS]
506 Format: <io>,<irq>,<dma>,<dma16>
507
508 gvp11= [HW,SCSI]
509
510 hashdist= [KNL,NUMA] Large hashes allocated during boot
511 are distributed across NUMA nodes. Defaults on
512 for IA-64, off otherwise.
513
514 hcl= [IA-64] SGI's Hardware Graph compatibility layer
515
516 hd= [EIDE] (E)IDE hard drive subsystem geometry
517 Format: <cyl>,<head>,<sect>
518
519 hd?= [HW] (E)IDE subsystem
520 hd?lun= See Documentation/ide.txt.
521
522 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
523 size of <nn>. This works even on boxes that have no
524 highmem otherwise. This also works to reduce highmem
525 size on bigger boxes.
526
527 hisax= [HW,ISDN]
528 See Documentation/isdn/README.HiSax.
529
530 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
531
532 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
533
534 i8042.direct [HW] Put keyboard port into non-translated mode
535 i8042.dumbkbd [HW] Pretend that controlled can only read data from
536 keyboard and can not control its state
537 (Don't attempt to blink the leds)
538 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
539 i8042.nomux [HW] Don't check presence of an active multiplexing
540 controller
541 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
542 controllers
543 i8042.panicblink=
544 [HW] Frequency with which keyboard LEDs should blink
545 when kernel panics (default is 0.5 sec)
546 i8042.reset [HW] Reset the controller during init and cleanup
547 i8042.unlock [HW] Unlock (ignore) the keylock
548
549 i810= [HW,DRM]
550
551 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
552 does not match list of supported models.
553 i8k.power_status
554 [HW] Report power status in /proc/i8k
555 (disabled by default)
556 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
557 capability is set.
558
559 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
560 See Documentation/mca.txt.
561
562 icn= [HW,ISDN]
563 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
564
565 ide= [HW] (E)IDE subsystem
566 Format: ide=nodma or ide=doubler or ide=reverse
567 See Documentation/ide.txt.
568
569 ide?= [HW] (E)IDE subsystem
570 Format: ide?=noprobe or chipset specific parameters.
571 See Documentation/ide.txt.
572
573 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
574 See Documentation/ide.txt.
575
576 idle= [HW]
577 Format: idle=poll or idle=halt
578
579 ihash_entries= [KNL]
580 Set number of hash buckets for inode cache.
581
582 in2000= [HW,SCSI]
583 See header of drivers/scsi/in2000.c.
584
585 init= [KNL]
586 Format: <full_path>
587 Run specified binary instead of /sbin/init as init
588 process.
589
590 initcall_debug [KNL] Trace initcalls as they are executed. Useful
591 for working out where the kernel is dying during
592 startup.
593
594 initrd= [BOOT] Specify the location of the initial ramdisk
595
596 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
597 Format: <irq>
598
599 inttest= [IA64]
600
601 io7= [HW] IO7 for Marvel based alpha systems
602 See comment before marvel_specify_io7 in
603 arch/alpha/kernel/core_marvel.c.
604
605 ip= [IP_PNP]
606 See Documentation/nfsroot.txt.
607
608 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
609 See comment before ip2_setup() in drivers/char/ip2.c.
610
611 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
612 See header of drivers/scsi/ips.c.
613
614 isapnp= [ISAPNP]
615 Format: <RDP>, <reset>, <pci_scan>, <verbosity>
616
617 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
618 Format: <cpu number>,...,<cpu number>
619 This option can be used to specify one or more CPUs
620 to isolate from the general SMP balancing and scheduling
621 algorithms. The only way to move a process onto or off
622 an "isolated" CPU is via the CPU affinity syscalls.
623 <cpu number> begins at 0 and the maximum value is
624 "number of CPUs in system - 1".
625
626 This option is the preferred way to isolate CPUs. The
627 alternative - manually setting the CPU mask of all tasks
628 in the system can cause problems and suboptimal load
629 balancer performance.
630
631 isp16= [HW,CD]
632 Format: <io>,<irq>,<dma>,<setup>
633
634 iucv= [HW,NET]
635
636 js= [HW,JOY] Analog joystick
637 See Documentation/input/joystick.txt.
638
639 keepinitrd [HW,ARM]
640
641 kstack=N [IA-32, X86-64] Print N words from the kernel stack
642 in oops dumps.
643
644 l2cr= [PPC]
645
646 lapic [IA-32,APIC] Enable the local APIC even if BIOS disabled it.
647
648 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
649 Format: addr:<io>,irq:<irq>
650
651 llsc*= [IA64]
652 See function print_params() in arch/ia64/sn/kernel/llsc4.c.
653
654 load_ramdisk= [RAM] List of ramdisks to load from floppy
655 See Documentation/ramdisk.txt.
656
657 lockd.udpport= [NFS]
658
659 lockd.tcpport= [NFS]
660
661 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
662 Format: <irq>
663
664 loglevel= All Kernel Messages with a loglevel smaller than the
665 console loglevel will be printed to the console. It can
666 also be changed with klogd or other programs. The
667 loglevels are defined as follows:
668
669 0 (KERN_EMERG) system is unusable
670 1 (KERN_ALERT) action must be taken immediately
671 2 (KERN_CRIT) critical conditions
672 3 (KERN_ERR) error conditions
673 4 (KERN_WARNING) warning conditions
674 5 (KERN_NOTICE) normal but significant condition
675 6 (KERN_INFO) informational
676 7 (KERN_DEBUG) debug-level messages
677
678 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
679 Format is n, nk, nM. n must be a power of two. The
680 default is set in kernel config.
681
682 lp=0 [LP] Specify parallel ports to use, e.g,
683 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
684 lp=reset first parallel port). 'lp=0' disables the
685 lp=auto printer driver. 'lp=reset' (which can be
686 specified in addition to the ports) causes
687 attached printers to be reset. Using
688 lp=port1,port2,... specifies the parallel ports
689 to associate lp devices with, starting with
690 lp0. A port specification may be 'none' to skip
691 that lp device, or a parport name such as
692 'parport0'. Specifying 'lp=auto' instead of a
693 port specification list means that device IDs
694 from each port should be examined, to see if
695 an IEEE 1284-compliant printer is attached; if
696 so, the driver will manage that printer.
697 See also header of drivers/char/lp.c.
698
699 lpj=n [KNL]
700 Sets loops_per_jiffy to given constant, thus avoiding
701 time-consuming boot-time autodetection (up to 250 ms per
702 CPU). 0 enables autodetection (default). To determine
703 the correct value for your kernel, boot with normal
704 autodetection and see what value is printed. Note that
705 on SMP systems the preset will be applied to all CPUs,
706 which is likely to cause problems if your CPUs need
707 significantly divergent settings. An incorrect value
708 will cause delays in the kernel to be wrong, leading to
709 unpredictable I/O errors and other breakage. Although
710 unlikely, in the extreme case this might damage your
711 hardware.
712
713 ltpc= [NET]
714 Format: <io>,<irq>,<dma>
715
716 mac5380= [HW,SCSI]
717 Format: <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
718
719 mac53c9x= [HW,SCSI]
720 Format: <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
721
722 machvec= [IA64]
723 Force the use of a particular machine-vector (machvec) in a generic
724 kernel. Example: machvec=hpzx1_swiotlb
725
726 mad16= [HW,OSS]
727 Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
728
729 maui= [HW,OSS]
730 Format: <io>,<irq>
731
732 max_loop= [LOOP] Maximum number of loopback devices that can
733 be mounted
734 Format: <1-256>
735
736 maxcpus= [SMP] Maximum number of processors that an SMP kernel
737 should make use of
738
739 max_luns= [SCSI] Maximum number of LUNs to probe
740 Should be between 1 and 2^32-1.
741
742 max_report_luns=
743 [SCSI] Maximum number of LUNs received
744 Should be between 1 and 16384.
745
746 mca-pentium [BUGS=IA-32]
747
748 mcatest= [IA-64]
749
750 mcd= [HW,CD]
751 Format: <port>,<irq>,<mitsumi_bug_93_wait>
752
753 mcdx= [HW,CD]
754
755 mce [IA-32] Machine Check Exception
756
757 md= [HW] RAID subsystems devices and level
758 See Documentation/md.txt.
759
760 mdacon= [MDA]
761 Format: <first>,<last>
762 Specifies range of consoles to be captured by the MDA.
763
764 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
765 Amount of memory to be used when the kernel is not able
766 to see the whole system memory or for test.
767 [IA-32] Use together with memmap= to avoid physical
768 address space collisions. Without memmap= PCI devices
769 could be placed at addresses belonging to unused RAM.
770
771 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
772 memory.
773
774 memmap=exactmap [KNL,IA-32] Enable setting of an exact
775 E820 memory map, as specified by the user.
776 Such memmap=exactmap lines can be constructed based on
777 BIOS output or other requirements. See the memmap=nn@ss
778 option description.
779
780 memmap=nn[KMG]@ss[KMG]
781 [KNL] Force usage of a specific region of memory
782 Region of memory to be used, from ss to ss+nn.
783
784 memmap=nn[KMG]#ss[KMG]
785 [KNL,ACPI] Mark specific memory as ACPI data.
786 Region of memory to be used, from ss to ss+nn.
787
788 memmap=nn[KMG]$ss[KMG]
789 [KNL,ACPI] Mark specific memory as reserved.
790 Region of memory to be used, from ss to ss+nn.
791
792 meye.*= [HW] Set MotionEye Camera parameters
793 See Documentation/video4linux/meye.txt.
794
795 mga= [HW,DRM]
796
797 mousedev.tap_time=
798 [MOUSE] Maximum time between finger touching and
799 leaving touchpad surface for touch to be considered
800 a tap and be reported as a left button click (for
801 touchpads working in absolute mode only).
802 Format: <msecs>
803 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
804 reporting absolute coordinates, such as tablets
805 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
806 reporting absolute coordinates, such as tablets
807
808 mpu401= [HW,OSS]
809 Format: <io>,<irq>
810
811 MTD_Partition= [MTD]
812 Format: <name>,<region-number>,<size>,<offset>
813
814 MTD_Region= [MTD]
815 Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
816
817 mtdparts= [MTD]
818 See drivers/mtd/cmdline.c.
819
820 mtouchusb.raw_coordinates=
821 [HW] Make the MicroTouch USB driver use raw coordinates ('y', default)
822 or cooked coordinates ('n')
823
824 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
825
826 NCR_D700= [HW,SCSI]
827 See header of drivers/scsi/NCR_D700.c.
828
829 ncr5380= [HW,SCSI]
830
831 ncr53c400= [HW,SCSI]
832
833 ncr53c400a= [HW,SCSI]
834
835 ncr53c406a= [HW,SCSI]
836
837 ncr53c8xx= [HW,SCSI]
838
839 netdev= [NET] Network devices parameters
840 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
841 Note that mem_start is often overloaded to mean
842 something different and driver-specific.
843
844 nfsaddrs= [NFS]
845 See Documentation/nfsroot.txt.
846
847 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
848 See Documentation/nfsroot.txt.
849
850 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
851
852 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
853 emulation library even if a 387 maths coprocessor
854 is present.
855
856 noalign [KNL,ARM]
857
858 noapic [SMP,APIC] Tells the kernel to not make use of any
859 IOAPICs that may be present in the system.
860
861 noasync [HW,M68K] Disables async and sync negotiation for
862 all devices.
863
864 nobats [PPC] Do not use BATs for mapping kernel lowmem
865 on "Classic" PPC cores.
866
867 nocache [ARM]
868
869 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
870
871 noexec [IA-64]
872
873 noexec [IA-32, X86-64]
874 noexec=on: enable non-executable mappings (default)
875 noexec=off: disable nn-executable mappings
876
877 nofxsr [BUGS=IA-32]
878
879 nohlt [BUGS=ARM]
880
881 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
882 instruction doesn't work correctly and not to
883 use it.
884
885 nohalt [IA-64] Tells the kernel not to use the power saving
886 function PAL_HALT_LIGHT when idle. This increases
887 power-consumption. On the positive side, it reduces
888 interrupt wake-up latency, which may improve performance
889 in certain environments such as networked servers or
890 real-time systems.
891
892 noirqdebug [IA-32] Disables the code which attempts to detect and
893 disable unhandled interrupt sources.
894
895 noisapnp [ISAPNP] Disables ISA PnP code.
896
897 noinitrd [RAM] Tells the kernel not to load any configured
898 initial RAM disk.
899
900 nointroute [IA-64]
901
902 nolapic [IA-32,APIC] Do not enable or use the local APIC.
903
904 noltlbs [PPC] Do not use large page/tlb entries for kernel
905 lowmem mapping on PPC40x.
906
907 nomce [IA-32] Machine Check Exception
908
909 noresidual [PPC] Don't use residual data on PReP machines.
910
911 noresume [SWSUSP] Disables resume and restore original swap space.
912
913 no-scroll [VGA] Disables scrollback.
914 This is required for the Braillex ib80-piezo Braille
915 reader made by F.H. Papenmeier (Germany).
916
917 nosbagart [IA-64]
918
919 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
920
921 nosync [HW,M68K] Disables sync negotiation for all devices.
922
923 notsc [BUGS=IA-32] Disable Time Stamp Counter
924
925 nousb [USB] Disable the USB subsystem
926
927 nowb [ARM]
928
929 opl3= [HW,OSS]
930 Format: <io>
931
932 opl3sa= [HW,OSS]
933 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
934
935 opl3sa2= [HW,OSS]
936 Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
937
938 oprofile.timer= [HW]
939 Use timer interrupt instead of performance counters
940
941 optcd= [HW,CD]
942 Format: <io>
943
944 osst= [HW,SCSI] SCSI Tape Driver
945 Format: <buffer_size>,<write_threshold>
946 See also Documentation/scsi/st.txt.
947
948 panic= [KNL] Kernel behaviour on panic
949 Format: <timeout>
950
951 parkbd.port= [HW] Parallel port number the keyboard adapter is
952 connected to, default is 0.
953 Format: <parport#>
954 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
955 0 for XT, 1 for AT (default is AT).
956 Format: <mode>
957
958 parport=0 [HW,PPT] Specify parallel ports. 0 disables.
959 parport=auto Use 'auto' to force the driver to use
960 parport=0xBBB[,IRQ[,DMA]] any IRQ/DMA settings detected (the
961 default is to ignore detected IRQ/DMA
962 settings because of possible
963 conflicts). You can specify the base
964 address, IRQ, and DMA settings; IRQ and
965 DMA should be numbers, or 'auto' (for
966 using detected settings on that
967 particular port), or 'nofifo' (to avoid
968 using a FIFO even if it is detected).
969 Parallel ports are assigned in the
970 order they are specified on the command
971 line, starting with parport0.
972
973 parport_init_mode=
974 [HW,PPT] Configure VIA parallel port to
975 operate in specific mode. This is
976 necessary on Pegasos computer where
977 firmware has no options for setting up
978 parallel port mode and sets it to
979 spp. Currently this function knows
980 686a and 8231 chips.
981 Format: [spp|ps2|epp|ecp|ecpepp]
982
983 pas2= [HW,OSS]
984 Format: <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
985
986 pas16= [HW,SCSI]
987 See header of drivers/scsi/pas16.c.
988
989 pcbit= [HW,ISDN]
990
991 pcd. [PARIDE]
992 See header of drivers/block/paride/pcd.c.
993 See also Documentation/paride.txt.
994
995 pci=option[,option...] [PCI] various PCI subsystem options:
996 off [IA-32] don't probe for the PCI bus
997 bios [IA-32] force use of PCI BIOS, don't access
998 the hardware directly. Use this if your machine
999 has a non-standard PCI host bridge.
1000 nobios [IA-32] disallow use of PCI BIOS, only direct
1001 hardware access methods are allowed. Use this
1002 if you experience crashes upon bootup and you
1003 suspect they are caused by the BIOS.
1004 conf1 [IA-32] Force use of PCI Configuration Mechanism 1.
1005 conf2 [IA-32] Force use of PCI Configuration Mechanism 2.
1006 nosort [IA-32] Don't sort PCI devices according to
1007 order given by the PCI BIOS. This sorting is done
1008 to get a device order compatible with older kernels.
1009 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1010 routing table. These calls are known to be buggy
1011 on several machines and they hang the machine when used,
1012 but on other computers it's the only way to get the
1013 interrupt routing table. Try this option if the kernel
1014 is unable to allocate IRQs or discover secondary PCI
1015 buses on your motherboard.
1016 rom [IA-32] Assign address space to expansion ROMs.
1017 Use with caution as certain devices share address
1018 decoders between ROMs and other resources.
1019 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be assigned
1020 automatically to PCI devices. You can make the kernel
1021 exclude IRQs of your ISA cards this way.
1022 lastbus=N [IA-32] Scan all buses till bus #N. Can be useful
1023 if the kernel is unable to find your secondary buses
1024 and you want to tell it explicitly which ones they are.
1025 assign-busses [IA-32] Always assign all PCI bus
1026 numbers ourselves, overriding
1027 whatever the firmware may have
1028 done.
1029 usepirqmask [IA-32] Honor the possible IRQ mask
1030 stored in the BIOS $PIR table. This is
1031 needed on some systems with broken
1032 BIOSes, notably some HP Pavilion N5400
1033 and Omnibook XE3 notebooks. This will
1034 have no effect if ACPI IRQ routing is
1035 enabled.
1036 noacpi [IA-32] Do not use ACPI for IRQ routing
1037 or for PCI scanning.
1038 routeirq Do IRQ routing for all PCI devices.
1039 This is normally done in pci_enable_device(),
1040 so this option is a temporary workaround
1041 for broken drivers that don't call it.
1042
1043 firmware [ARM] Do not re-enumerate the bus but
1044 instead just use the configuration
1045 from the bootloader. This is currently
1046 used on IXP2000 systems where the
1047 bus has to be configured a certain way
1048 for adjunct CPUs.
1049
1050 pcmv= [HW,PCMCIA] BadgePAD 4
1051
1052 pd. [PARIDE]
1053 See Documentation/paride.txt.
1054
1055 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1056 boot time.
1057 Format: { 0 | 1 }
1058 See arch/parisc/kernel/pdc_chassis.c
1059
1060 pf. [PARIDE]
1061 See Documentation/paride.txt.
1062
1063 pg. [PARIDE]
1064 See Documentation/paride.txt.
1065
1066 pirq= [SMP,APIC] Manual mp-table setup
1067 See Documentation/i386/IO-APIC.txt.
1068
1069 plip= [PPT,NET] Parallel port network link
1070 Format: { parport<nr> | timid | 0 }
1071 See also Documentation/parport.txt.
1072
1073 pnpacpi= [ACPI]
1074 { off }
1075
1076 pnpbios= [ISAPNP]
1077 { on | off | curr | res | no-curr | no-res }
1078
1079 pnp_reserve_irq=
1080 [ISAPNP] Exclude IRQs for the autoconfiguration
1081
1082 pnp_reserve_dma=
1083 [ISAPNP] Exclude DMAs for the autoconfiguration
1084
1085 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1086 Ranges are in pairs (I/O port base and size).
1087
1088 pnp_reserve_mem=
1089 [ISAPNP] Exclude memory regions for the autoconfiguration
1090 Ranges are in pairs (memory base and size).
1091
1092 profile= [KNL] Enable kernel profiling via /proc/profile
1093 { schedule | <number> }
1094 (param: schedule - profile schedule points}
1095 (param: profile step/bucket size as a power of 2 for
1096 statistical time based profiling)
1097
1098 processor.max_cstate= [HW, ACPI]
1099 Limit processor to maximum C-state
1100 max_cstate=9 overrides any DMI blacklist limit.
1101
1102 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1103 before loading.
1104 See Documentation/ramdisk.txt.
1105
1106 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1107 probe for (bare|imps|exps).
1108 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1109 per second.
1110 psmouse.resetafter=
1111 [HW,MOUSE] Try to reset the device after so many bad packets
1112 (0 = never).
1113 psmouse.resolution=
1114 [HW,MOUSE] Set desired mouse resolution, in dpi.
1115 psmouse.smartscroll=
1116 [HW,MOUSE] Controls Logitech smartscroll autorepeat,
1117 0 = disabled, 1 = enabled (default).
1118
1119 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1120 Format: <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1121
1122 pt. [PARIDE]
1123 See Documentation/paride.txt.
1124
1125 quiet= [KNL] Disable log messages
1126
1127 r128= [HW,DRM]
1128
1129 raid= [HW,RAID]
1130 See Documentation/md.txt.
1131
1132 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1133 See Documentation/ramdisk.txt.
1134
1135 ramdisk_blocksize=
1136 [RAM]
1137 See Documentation/ramdisk.txt.
1138
1139 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1140 New name for the ramdisk parameter.
1141 See Documentation/ramdisk.txt.
1142
1143 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1144 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1145 See arch/*/kernel/reboot.c.
1146
1147 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1148
1149 resume= [SWSUSP] Specify the partition device for software suspension
1150
1151 rhash_entries= [KNL,NET]
1152 Set number of hash buckets for route cache
1153
1154 riscom8= [HW,SERIAL]
1155 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1156
1157 ro [KNL] Mount root device read-only on boot
1158
1159 root= [KNL] Root filesystem
1160
1161 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1162 mount the root filesystem
1163
1164 rootflags= [KNL] Set root filesystem mount option string
1165
1166 rootfstype= [KNL] Set root filesystem type
1167
1168 rw [KNL] Mount root device read-write on boot
1169
1170 S [KNL] Run init in single mode
1171
1172 sa1100ir [NET]
1173 See drivers/net/irda/sa1100_ir.c.
1174
1175 sb= [HW,OSS]
1176 Format: <io>,<irq>,<dma>,<dma2>
1177
1178 sbni= [NET] Granch SBNI12 leased line adapter
1179
1180 sbpcd= [HW,CD] Soundblaster CD adapter
1181 Format: <io>,<type>
1182 See a comment before function sbpcd_setup() in
1183 drivers/cdrom/sbpcd.c.
1184
1185 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1186 Format: <io>[,<timeout>[,<isapnp>]]
1187
1188 scsi_debug_*= [SCSI]
1189 See drivers/scsi/scsi_debug.c.
1190
1191 scsi_default_dev_flags=
1192 [SCSI] SCSI default device flags
1193 Format: <integer>
1194
1195 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1196 Format: <vendor>:<model>:<flags>
1197 (flags are integer value)
1198
1199 scsi_logging= [SCSI]
1200
1201 selinux [SELINUX] Disable or enable SELinux at boot time.
1202 Format: { "0" | "1" }
1203 See security/selinux/Kconfig help text.
1204 0 -- disable.
1205 1 -- enable.
1206 Default value is set via kernel config option.
1207 If enabled at boot time, /selinux/disable can be used
1208 later to disable prior to initial policy load.
1209
1210 serialnumber [BUGS=IA-32]
1211
1212 sg_def_reserved_size=
1213 [SCSI]
1214
1215 sgalaxy= [HW,OSS]
1216 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1217
1218 shapers= [NET]
1219 Maximal number of shapers.
1220
1221 sim710= [SCSI,HW]
1222 See header of drivers/scsi/sim710.c.
1223
1224 simeth= [IA-64]
1225 simscsi=
1226
1227 sjcd= [HW,CD]
1228 Format: <io>,<irq>,<dma>
1229 See header of drivers/cdrom/sjcd.c.
1230
1231 slram= [HW,MTD]
1232
1233 smart2= [HW]
1234 Format: <io1>[,<io2>[,...,<io8>]]
1235
1236 snd-ad1816a= [HW,ALSA]
1237
1238 snd-ad1848= [HW,ALSA]
1239
1240 snd-ali5451= [HW,ALSA]
1241
1242 snd-als100= [HW,ALSA]
1243
1244 snd-als4000= [HW,ALSA]
1245
1246 snd-azt2320= [HW,ALSA]
1247
1248 snd-cmi8330= [HW,ALSA]
1249
1250 snd-cmipci= [HW,ALSA]
1251
1252 snd-cs4231= [HW,ALSA]
1253
1254 snd-cs4232= [HW,ALSA]
1255
1256 snd-cs4236= [HW,ALSA]
1257
1258 snd-cs4281= [HW,ALSA]
1259
1260 snd-cs46xx= [HW,ALSA]
1261
1262 snd-dt019x= [HW,ALSA]
1263
1264 snd-dummy= [HW,ALSA]
1265
1266 snd-emu10k1= [HW,ALSA]
1267
1268 snd-ens1370= [HW,ALSA]
1269
1270 snd-ens1371= [HW,ALSA]
1271
1272 snd-es968= [HW,ALSA]
1273
1274 snd-es1688= [HW,ALSA]
1275
1276 snd-es18xx= [HW,ALSA]
1277
1278 snd-es1938= [HW,ALSA]
1279
1280 snd-es1968= [HW,ALSA]
1281
1282 snd-fm801= [HW,ALSA]
1283
1284 snd-gusclassic= [HW,ALSA]
1285
1286 snd-gusextreme= [HW,ALSA]
1287
1288 snd-gusmax= [HW,ALSA]
1289
1290 snd-hdsp= [HW,ALSA]
1291
1292 snd-ice1712= [HW,ALSA]
1293
1294 snd-intel8x0= [HW,ALSA]
1295
1296 snd-interwave= [HW,ALSA]
1297
1298 snd-interwave-stb=
1299 [HW,ALSA]
1300
1301 snd-korg1212= [HW,ALSA]
1302
1303 snd-maestro3= [HW,ALSA]
1304
1305 snd-mpu401= [HW,ALSA]
1306
1307 snd-mtpav= [HW,ALSA]
1308
1309 snd-nm256= [HW,ALSA]
1310
1311 snd-opl3sa2= [HW,ALSA]
1312
1313 snd-opti92x-ad1848=
1314 [HW,ALSA]
1315
1316 snd-opti92x-cs4231=
1317 [HW,ALSA]
1318
1319 snd-opti93x= [HW,ALSA]
1320
1321 snd-pmac= [HW,ALSA]
1322
1323 snd-rme32= [HW,ALSA]
1324
1325 snd-rme96= [HW,ALSA]
1326
1327 snd-rme9652= [HW,ALSA]
1328
1329 snd-sb8= [HW,ALSA]
1330
1331 snd-sb16= [HW,ALSA]
1332
1333 snd-sbawe= [HW,ALSA]
1334
1335 snd-serial= [HW,ALSA]
1336
1337 snd-sgalaxy= [HW,ALSA]
1338
1339 snd-sonicvibes= [HW,ALSA]
1340
1341 snd-sun-amd7930=
1342 [HW,ALSA]
1343
1344 snd-sun-cs4231= [HW,ALSA]
1345
1346 snd-trident= [HW,ALSA]
1347
1348 snd-usb-audio= [HW,ALSA,USB]
1349
1350 snd-via82xx= [HW,ALSA]
1351
1352 snd-virmidi= [HW,ALSA]
1353
1354 snd-wavefront= [HW,ALSA]
1355
1356 snd-ymfpci= [HW,ALSA]
1357
1358 sonicvibes= [HW,OSS]
1359 Format: <reverb>
1360
1361 sonycd535= [HW,CD]
1362 Format: <io>[,<irq>]
1363
1364 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1365 See Documentation/sonypi.txt
1366
1367 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1368 See Documentation/specialix.txt.
1369
1370 spia_io_base= [HW,MTD]
1371 spia_fio_base=
1372 spia_pedr=
1373 spia_peddr=
1374
1375 sscape= [HW,OSS]
1376 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1377
1378 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1379 See Documentation/scsi/st.txt.
1380
1381 st0x= [HW,SCSI]
1382 See header of drivers/scsi/seagate.c.
1383
1384 sti= [PARISC,HW]
1385 Format: <num>
1386 Set the STI (builtin display/keyboard on the HP-PARISC
1387 machines) console (graphic card) which should be used
1388 as the initial boot-console.
1389 See also comment in drivers/video/console/sticore.c.
1390
1391 sti_font= [HW]
1392 See comment in drivers/video/console/sticore.c.
1393
1394 stifb= [HW]
1395 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1396
1397 stram_swap= [HW,M68k]
1398
1399 swiotlb= [IA-64] Number of I/O TLB slabs
1400
1401 switches= [HW,M68k]
1402
1403 sym53c416= [HW,SCSI]
1404 See header of drivers/scsi/sym53c416.c.
1405
1406 t128= [HW,SCSI]
1407 See header of drivers/scsi/t128.c.
1408
1409 tdfx= [HW,DRM]
1410
1411 thash_entries= [KNL,NET]
1412 Set number of hash buckets for TCP connection
1413
1414 time Show timing data prefixed to each printk message line
1415
1416 tipar.timeout= [HW,PPT]
1417 Set communications timeout in tenths of a second
1418 (default 15).
1419
1420 tipar.delay= [HW,PPT]
1421 Set inter-bit delay in microseconds (default 10).
1422
1423 tmc8xx= [HW,SCSI]
1424 See header of drivers/scsi/seagate.c.
1425
1426 tmscsim= [HW,SCSI]
1427 See comment before function dc390_setup() in
1428 drivers/scsi/tmscsim.c.
1429
1430 tp720= [HW,PS2]
1431
1432 trix= [HW,OSS] MediaTrix AudioTrix Pro
1433 Format: <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1434
1435 tsdev.xres= [TS] Horizontal screen resolution.
1436 tsdev.yres= [TS] Vertical screen resolution.
1437
1438 turbografx.map[2|3]=
1439 [HW,JOY] TurboGraFX parallel port interface
1440 Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1441 See also Documentation/input/joystick-parport.txt
1442
1443 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1444 See header of drivers/scsi/u14-34f.c.
1445
1446 uart401= [HW,OSS]
1447 Format: <io>,<irq>
1448
1449 uart6850= [HW,OSS]
1450 Format: <io>,<irq>
1451
1452 usb-handoff [HW] Enable early USB BIOS -> OS handoff
1453
1454 usbhid.mousepoll=
1455 [USBHID] The interval which mice are to be polled at.
1456
1457 video= [FB] Frame buffer configuration
1458 See Documentation/fb/modedb.txt.
1459
1460 vga= [BOOT,IA-32] Select a particular video mode
1461 See Documentation/i386/boot.txt and Documentation/svga.txt.
1462 Use vga=ask for menu.
1463 This is actually a boot loader parameter; the value is
1464 passed to the kernel using a special protocol.
1465
1466 vmalloc=nn[KMG] [KNL,BOOT] forces the vmalloc area to have an exact
1467 size of <nn>. This can be used to increase the
1468 minimum size (128MB on x86). It can also be used to
1469 decrease the size and leave more room for directly
1470 mapped kernel RAM.
1471
1472 vmhalt= [KNL,S390]
1473
1474 vmpoff= [KNL,S390]
1475
1476 waveartist= [HW,OSS]
1477 Format: <io>,<irq>,<dma>,<dma2>
1478
1479 wd33c93= [HW,SCSI]
1480 See header of drivers/scsi/wd33c93.c.
1481
1482 wd7000= [HW,SCSI]
1483 See header of drivers/scsi/wd7000.c.
1484
1485 wdt= [WDT] Watchdog
1486 See Documentation/watchdog/watchdog.txt.
1487
1488 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1489 xd_geo= See header of drivers/block/xd.c.
1490
1491 xirc2ps_cs= [NET,PCMCIA]
1492 Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1493
1494
1495
1496Changelog:
1497
1498 The last known update (for 2.4.0) - the changelog was not kept before.
1499 2000-06-?? Mr. Unknown
1500
1501 Update for 2.5.49, description for most of the options introduced,
1502 references to other documentation (C files, READMEs, ..), added S390,
1503 PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
1504 reformatting.
1505 2002-11-24 Petr Baudis <pasky@ucw.cz>
1506 Randy Dunlap <randy.dunlap@verizon.net>
1507
1508TODO:
1509
1510 Add documentation for ALSA options.
1511 Add more DRM drivers.