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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
Randy Dunlapa9913042005-10-23 12:57:11 -070020The text in square brackets at the beginning of the description states the
Linus Torvalds1da177e2005-04-16 15:20:36 -070021restrictions 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.
Randy Dunlapa9913042005-10-23 12:57:11 -070030 DEVFS devfs support is enabled.
31 DRM Direct Rendering Management support is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 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.
Adrian Bunk41e2e8b2005-07-12 13:58:33 -070040 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 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.
Matthew Wilcox309e57d2006-03-05 22:33:34 -070052 MSI Message Signaled Interrupts (PCI).
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 MTD MTD support is enabled.
54 NET Appropriate network support is enabled.
55 NUMA NUMA support is enabled.
56 NFS Appropriate NFS support is enabled.
57 OSS OSS sound support is enabled.
58 PARIDE The ParIDE subsystem is enabled.
59 PARISC The PA-RISC architecture is enabled.
60 PCI PCI bus support is enabled.
61 PCMCIA The PCMCIA subsystem is enabled.
62 PNP Plug & Play support is enabled.
63 PPC PowerPC architecture is enabled.
64 PPT Parallel port support is enabled.
65 PS2 Appropriate PS/2 support is enabled.
66 RAM RAM disk support is enabled.
67 S390 S390 architecture is enabled.
68 SCSI Appropriate SCSI support is enabled.
69 A lot of drivers has their options described inside of
70 Documentation/scsi/.
71 SELINUX SELinux support is enabled.
72 SERIAL Serial support is enabled.
73 SMP The kernel is an SMP kernel.
74 SPARC Sparc architecture is enabled.
Randy Dunlapa9913042005-10-23 12:57:11 -070075 SWSUSP Software suspend is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 TS Appropriate touchscreen support is enabled.
77 USB USB support is enabled.
78 USBHID USB Human Interface Device support is enabled.
79 V4L Video For Linux support is enabled.
80 VGA The VGA console has been enabled.
81 VT Virtual terminal support is enabled.
82 WDT Watchdog support is enabled.
83 XT IBM PC/XT MFM hard disk support is enabled.
84 X86-64 X86-64 architecture is enabled.
85 More X86-64 boot options can be found in
86 Documentation/x86_64/boot-options.txt .
87
88In addition, the following text indicates that the option:
89
90 BUGS= Relates to possible processor bugs on the said processor.
91 KNL Is a kernel start-up parameter.
92 BOOT Is a boot loader parameter.
93
94Parameters denoted with BOOT are actually interpreted by the boot
95loader, and have no meaning to the kernel directly.
96Do not modify the syntax of boot loader parameters without extreme
97need or coordination with <Documentation/i386/boot.txt>.
98
99Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
100a trailing = on the name of any parameter states that that parameter will
101be entered as an environment variable, whereas its absence indicates that
102it will appear as a kernel argument readable via /proc/cmdline by programs
103running once the system is up.
104
105 53c7xx= [HW,SCSI] Amiga SCSI controllers
106 See header of drivers/scsi/53c7xx.c.
107 See also Documentation/scsi/ncr53c7xx.txt.
108
Randy Dunlapa9913042005-10-23 12:57:11 -0700109 acpi= [HW,ACPI] Advanced Configuration and Power Interface
110 Format: { force | off | ht | strict | noirq }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 force -- enable ACPI if default was off
112 off -- disable ACPI if default was on
113 noirq -- do not use ACPI for IRQ routing
114 ht -- run only enough ACPI to enable Hyper Threading
Randy Dunlapa9913042005-10-23 12:57:11 -0700115 strict -- Be less tolerant of platforms that are not
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 strictly ACPI specification compliant.
117
118 See also Documentation/pm.txt, pci=noacpi
119
120 acpi_sleep= [HW,ACPI] Sleep options
121 Format: { s3_bios, s3_mode }
122 See Documentation/power/video.txt
Randy Dunlapa9913042005-10-23 12:57:11 -0700123
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Randy Dunlapa9913042005-10-23 12:57:11 -0700125 Format: { level | edge | high | low }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126
Randy Dunlapa9913042005-10-23 12:57:11 -0700127 acpi_irq_balance [HW,ACPI]
128 ACPI will balance active IRQs
129 default in APIC mode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130
Randy Dunlapa9913042005-10-23 12:57:11 -0700131 acpi_irq_nobalance [HW,ACPI]
132 ACPI will not move active IRQs (default)
133 default in PIC mode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
Randy Dunlapa9913042005-10-23 12:57:11 -0700135 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
136 use by PCI
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 Format: <irq>,<irq>...
138
Randy Dunlapa9913042005-10-23 12:57:11 -0700139 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 Format: <irq>,<irq>...
141
142 acpi_osi= [HW,ACPI] empty param disables _OSI
143
144 acpi_serialize [HW,ACPI] force serialization of AML methods
145
146 acpi_skip_timer_override [HW,ACPI]
147 Recognize and ignore IRQ0/pin2 Interrupt Override.
148 For broken nForce2 BIOS resulting in XT-PIC timer.
149
150 acpi_dbg_layer= [HW,ACPI]
151 Format: <int>
Randy Dunlapa9913042005-10-23 12:57:11 -0700152 Each bit of the <int> indicates an ACPI debug layer,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 1: enable, 0: disable. It is useful for boot time
154 debugging. After system has booted up, it can be set
155 via /proc/acpi/debug_layer.
156
157 acpi_dbg_level= [HW,ACPI]
158 Format: <int>
Randy Dunlapa9913042005-10-23 12:57:11 -0700159 Each bit of the <int> indicates an ACPI debug level,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 1: enable, 0: disable. It is useful for boot time
161 debugging. After system has booted up, it can be set
162 via /proc/acpi/debug_level.
163
164 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
165
Luming Yu30e332f2005-08-12 00:31:00 -0400166 acpi_generic_hotkey [HW,ACPI]
167 Allow consolidated generic hotkey driver to
Randy Dunlapa9913042005-10-23 12:57:11 -0700168 override platform specific driver.
Luming Yu30e332f2005-08-12 00:31:00 -0400169 See also Documentation/acpi-hotkey.txt.
170
Chuck Ebbert66759a02005-09-12 18:49:25 +0200171 enable_timer_pin_1 [i386,x86-64]
172 Enable PIN 1 of APIC timer
Randy Dunlapa9913042005-10-23 12:57:11 -0700173 Can be useful to work around chipset bugs
174 (in particular on some ATI chipsets).
Chuck Ebbert66759a02005-09-12 18:49:25 +0200175 The kernel tries to set a reasonable default.
176
177 disable_timer_pin_1 [i386,x86-64]
178 Disable PIN 1 of APIC timer
179 Can be useful to work around chipset bugs.
180
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 ad1816= [HW,OSS]
182 Format: <io>,<irq>,<dma>,<dma2>
183 See also Documentation/sound/oss/AD1816.
184
185 ad1848= [HW,OSS]
186 Format: <io>,<irq>,<dma>,<dma2>,<type>
187
188 adlib= [HW,OSS]
189 Format: <io>
Randy Dunlapa9913042005-10-23 12:57:11 -0700190
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 advansys= [HW,SCSI]
192 See header of drivers/scsi/advansys.c.
193
194 advwdt= [HW,WDT] Advantech WDT
195 Format: <iostart>,<iostop>
196
197 aedsp16= [HW,OSS] Audio Excel DSP 16
198 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
199 See also header of sound/oss/aedsp16.c.
Randy Dunlapa9913042005-10-23 12:57:11 -0700200
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 aha152x= [HW,SCSI]
202 See Documentation/scsi/aha152x.txt.
203
204 aha1542= [HW,SCSI]
205 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
206
207 aic7xxx= [HW,SCSI]
208 See Documentation/scsi/aic7xxx.txt.
209
210 aic79xx= [HW,SCSI]
211 See Documentation/scsi/aic79xx.txt.
212
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 amijoy.map= [HW,JOY] Amiga joystick support
214 Map of devices attached to JOY0DAT and JOY1DAT
215 Format: <a>,<b>
216 See also Documentation/kernel/input/joystick.txt
217
218 analog.map= [HW,JOY] Analog joystick and gamepad support
219 Specifies type or capabilities of an analog joystick
220 connected to one of 16 gameports
221 Format: <type1>,<type2>,..<type16>
222
Randy Dunlapa9913042005-10-23 12:57:11 -0700223 apc= [HW,SPARC]
224 Power management functions (SPARCstation-4/5 + deriv.)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 Format: noidle
226 Disable APC CPU standby support. SPARCstation-Fox does
227 not play well with APC CPU idle - disable it if you have
228 APC and your system crashes randomly.
229
Randy Dunlapa9913042005-10-23 12:57:11 -0700230 apic= [APIC,i386] Change the output verbosity whilst booting
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 Format: { quiet (default) | verbose | debug }
232 Change the amount of debugging information output
233 when initialising the APIC and IO-APIC components.
Randy Dunlapa9913042005-10-23 12:57:11 -0700234
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 apm= [APM] Advanced Power Management
236 See header of arch/i386/kernel/apm.c.
237
238 applicom= [HW]
239 Format: <mem>,<irq>
Randy Dunlapa9913042005-10-23 12:57:11 -0700240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
242 Format: <io>,<irq>,<nodeID>
243
244 ataflop= [HW,M68k]
245
246 atarimouse= [HW,MOUSE] Atari Mouse
247
248 atascsi= [HW,SCSI] Atari SCSI
249
250 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
251 EzKey and similar keyboards
252
253 atkbd.reset= [HW] Reset keyboard during initialization
254
Randy Dunlapa9913042005-10-23 12:57:11 -0700255 atkbd.set= [HW] Select keyboard code set
256 Format: <int> (2 = AT (default), 3 = PS/2)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
258 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
259 keyboards
260
261 atkbd.softraw= [HW] Choose between synthetic and real raw mode
262 Format: <bool> (0 = real, 1 = synthetic (default))
Randy Dunlapa9913042005-10-23 12:57:11 -0700263
264 atkbd.softrepeat= [HW]
265 Use software keyboard repeat
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
267 autotest [IA64]
268
269 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
270 Format: <io>,<memsize>,<isapnp>
Randy Dunlapa9913042005-10-23 12:57:11 -0700271
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 aztcd= [HW,CD] Aztech CD268 CDROM driver
273 Format: <io>,0x79 (?)
274
275 baycom_epp= [HW,AX25]
276 Format: <io>,<mode>
Randy Dunlapa9913042005-10-23 12:57:11 -0700277
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
279 Format: <io>,<mode>
280 See header of drivers/net/hamradio/baycom_par.c.
281
Randy Dunlapa9913042005-10-23 12:57:11 -0700282 baycom_ser_fdx= [HW,AX25]
283 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 Format: <io>,<irq>,<mode>[,<baud>]
285 See header of drivers/net/hamradio/baycom_ser_fdx.c.
286
Randy Dunlapa9913042005-10-23 12:57:11 -0700287 baycom_ser_hdx= [HW,AX25]
288 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 Format: <io>,<irq>,<mode>
290 See header of drivers/net/hamradio/baycom_ser_hdx.c.
291
292 blkmtd_device= [HW,MTD]
293 blkmtd_erasesz=
294 blkmtd_ro=
295 blkmtd_bs=
296 blkmtd_count=
297
298 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
Randy Dunlapa9913042005-10-23 12:57:11 -0700299 bttv.radio= Most important insmod options are available as
300 kernel args too.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
302 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
303
304 BusLogic= [HW,SCSI]
305 See drivers/scsi/BusLogic.c, comment before function
306 BusLogic_ParseDriverOptions().
307
308 c101= [NET] Moxa C101 synchronous serial card
309
310 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
311 Sometimes CPU hardware bugs make them report the cache
312 size incorrectly. The kernel will attempt work arounds
313 to fix known problems, but for some CPUs it is not
314 possible to determine what the correct size should be.
315 This option provides an override for these situations.
316
317 cdu31a= [HW,CD]
318 Format: <io>,<irq>[,PAS]
319 See header of drivers/cdrom/cdu31a.c.
320
321 chandev= [HW,NET] Generic channel device initialisation
322
323 checkreqprot [SELINUX] Set initial checkreqprot flag value.
324 Format: { "0" | "1" }
325 See security/selinux/Kconfig help text.
Randy Dunlapa9913042005-10-23 12:57:11 -0700326 0 -- check protection applied by kernel (includes
327 any implied execute protection).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 1 -- check protection requested by application.
329 Default value is set via a kernel config option.
Randy Dunlapa9913042005-10-23 12:57:11 -0700330 Value can be changed at runtime via
331 /selinux/checkreqprot.
332
333 clock= [BUGS=IA-32,HW] gettimeofday timesource override.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 Forces specified timesource (if avaliable) to be used
Randy Dunlapa9913042005-10-23 12:57:11 -0700335 when calculating gettimeofday(). If specicified
336 timesource is not avalible, it defaults to PIT.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 Format: { pit | tsc | cyclone | pmtmr }
338
Andi Kleenf9262c12006-03-08 17:57:25 -0800339 disable_8254_timer
340 enable_8254_timer
341 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
342 over the 8254 in addition to over the IO-APIC. The
343 kernel tries to set a sensible default.
344
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 hpet= [IA-32,HPET] option to disable HPET and use PIT.
346 Format: disable
347
348 cm206= [HW,CD]
349 Format: { auto | [<io>,][<irq>] }
350
351 com20020= [HW,NET] ARCnet - COM20020 chipset
Randy Dunlapa9913042005-10-23 12:57:11 -0700352 Format:
353 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
355 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
356 Format: <io>[,<irq>]
357
Randy Dunlapa9913042005-10-23 12:57:11 -0700358 com90xx= [HW,NET]
359 ARCnet - COM90xx chipset (memory-mapped buffers)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 Format: <io>[,<irq>[,<memstart>]]
361
362 condev= [HW,S390] console device
363 conmode=
Randy Dunlapa9913042005-10-23 12:57:11 -0700364
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 console= [KNL] Output console device and options.
366
367 tty<n> Use the virtual console device <n>.
368
369 ttyS<n>[,options]
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800370 ttyUSB0[,options]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 Use the specified serial port. The options are of
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800372 the form "bbbbpnf", where "bbbb" is the baud rate,
373 "p" is parity ("n", "o", or "e"), "n" is number of
374 bits, and "f" is flow control ("r" for RTS or
375 omit it). Default is "9600n8".
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800377 See Documentation/serial-console.txt for more
378 information. See
379 Documentation/networking/netconsole.txt for an
380 alternative.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381
382 uart,io,<addr>[,options]
383 uart,mmio,<addr>[,options]
384 Start an early, polled-mode console on the 8250/16550
385 UART at the specified I/O port or MMIO address,
386 switching to the matching ttyS device later. The
387 options are the same as for ttyS, above.
388
389 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Randy Dunlapa9913042005-10-23 12:57:11 -0700390 Format:
391 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
393 cpia_pp= [HW,PPT]
394 Format: { parport<nr> | auto | none }
395
Eric W. Biedermandc009d92005-06-25 14:57:52 -0700396 crashkernel=nn[KMG]@ss[KMG]
397 [KNL] Reserve a chunk of physical memory to
398 hold a kernel to switch to with kexec on panic.
399
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 cs4232= [HW,OSS]
401 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
402
403 cs89x0_dma= [HW,NET]
404 Format: <dma>
405
406 cs89x0_media= [HW,NET]
407 Format: { rj45 | aui | bnc }
Randy Dunlapa9913042005-10-23 12:57:11 -0700408
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
Randy Dunlapa9913042005-10-23 12:57:11 -0700410
411 dasd= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 See header of drivers/s390/block/dasd_devmap.c.
413
414 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
415 (one device per port)
416 Format: <port#>,<type>
417 See also Documentation/input/joystick-parport.txt
418
419 debug [KNL] Enable kernel debugging (events log level).
420
421 decnet= [HW,NET]
422 Format: <area>[,<node>]
423 See also Documentation/networking/decnet.txt.
424
425 devfs= [DEVFS]
426 See Documentation/filesystems/devfs/boot-options.
427
428 dhash_entries= [KNL]
429 Set number of hash buckets for dentry cache.
Randy Dunlapa9913042005-10-23 12:57:11 -0700430
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 digi= [HW,SERIAL]
432 IO parameters + enable/disable command.
433
434 digiepca= [HW,SERIAL]
435 See drivers/char/README.epca and
436 Documentation/digiepca.txt.
437
438 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
439 support available.
440 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
441
442 dmasound= [HW,OSS] Sound subsystem buffers
443
444 dscc4.setup= [NET]
445
446 dtc3181e= [HW,SCSI]
447
Randy Dunlapa9913042005-10-23 12:57:11 -0700448 earlyprintk= [IA-32,X86-64]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 earlyprintk=vga
450 earlyprintk=serial[,ttySn[,baudrate]]
451
Randy Dunlapa9913042005-10-23 12:57:11 -0700452 Append ",keep" to not disable it when the real console
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 takes over.
454
455 Only vga or serial at a time, not both.
456
457 Currently only ttyS0 and ttyS1 are supported.
458
459 Interaction with the standard serial driver is not
460 very good.
461
462 The VGA output is eventually overwritten by the real
463 console.
464
465 eata= [HW,SCSI]
466
Len Brown53f11d42005-12-05 16:46:36 -0500467 ec_intr= [HW,ACPI] ACPI Embedded Controller interrupt mode
468 Format: <int>
469 0: polling mode
470 non-0: interrupt mode (default)
471
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 eda= [HW,PS2]
473
474 edb= [HW,PS2]
475
476 edd= [EDD]
477 Format: {"of[f]" | "sk[ipmbr]"}
478 See comment in arch/i386/boot/edd.S
479
Randy Dunlapa9913042005-10-23 12:57:11 -0700480 eicon= [HW,ISDN]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 Format: <id>,<membase>,<irq>
482
483 eisa_irq_edge= [PARISC,HW]
484 See header of drivers/parisc/eisa.c.
485
486 elanfreq= [IA-32]
487 See comment before function elanfreq_setup() in
488 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
489
490 elevator= [IOSCHED]
Randy Dunlap16ab3ad2006-01-14 13:21:20 -0800491 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
Randy Dunlapa9913042005-10-23 12:57:11 -0700492 See Documentation/block/as-iosched.txt and
493 Documentation/block/deadline-iosched.txt for details.
494
Vivek Goyalaac04b32006-01-09 20:51:47 -0800495 elfcorehdr= [IA-32, X86_64]
Randy Dunlapa9913042005-10-23 12:57:11 -0700496 Specifies physical address of start of kernel core
Vivek Goyalaac04b32006-01-09 20:51:47 -0800497 image elf header. Generally kexec loader will
498 pass this option to capture kernel.
499 See Documentation/kdump/kdump.txt for details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500
501 enforcing [SELINUX] Set initial enforcing status.
502 Format: {"0" | "1"}
503 See security/selinux/Kconfig help text.
504 0 -- permissive (log only, no denials).
505 1 -- enforcing (deny and log).
506 Default value is 0.
507 Value can be changed at runtime via /selinux/enforce.
508
509 es1370= [HW,OSS]
510 Format: <lineout>[,<micbias>]
511 See also header of sound/oss/es1370.c.
512
513 es1371= [HW,OSS]
514 Format: <spdif>,[<nomix>,[<amplifier>]]
515 See also header of sound/oss/es1371.c.
Randy Dunlapa9913042005-10-23 12:57:11 -0700516
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 ether= [HW,NET] Ethernet cards parameters
518 This option is obsoleted by the "netdev=" option, which
519 has equivalent usage. See its documentation for details.
520
521 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
522 Format: <io>[,<irq>]
523
524 fd_mcs= [HW,SCSI]
525 See header of drivers/scsi/fd_mcs.c.
526
527 fdomain= [HW,SCSI]
528 See header of drivers/scsi/fdomain.c.
529
530 floppy= [HW]
531 See Documentation/floppy.txt.
532
533 ftape= [HW] Floppy Tape subsystem debugging options.
534 See Documentation/ftape.txt.
535
536 gamecon.map[2|3]=
537 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
538 support via parallel port (up to 5 devices per port)
539 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
540 See also Documentation/input/joystick-parport.txt
541
542 gamma= [HW,DRM]
543
544 gdth= [HW,SCSI]
545 See header of drivers/scsi/gdth.c.
546
547 gpt [EFI] Forces disk with valid GPT signature but
548 invalid Protective MBR to be treated as GPT.
549
550 gscd= [HW,CD]
551 Format: <io>
552
553 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
554
555 gus= [HW,OSS]
556 Format: <io>,<irq>,<dma>,<dma16>
Randy Dunlapa9913042005-10-23 12:57:11 -0700557
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 gvp11= [HW,SCSI]
559
560 hashdist= [KNL,NUMA] Large hashes allocated during boot
561 are distributed across NUMA nodes. Defaults on
562 for IA-64, off otherwise.
Randy Dunlapa9913042005-10-23 12:57:11 -0700563 Format: 0 | 1 (for off | on)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564
565 hcl= [IA-64] SGI's Hardware Graph compatibility layer
566
567 hd= [EIDE] (E)IDE hard drive subsystem geometry
568 Format: <cyl>,<head>,<sect>
569
570 hd?= [HW] (E)IDE subsystem
571 hd?lun= See Documentation/ide.txt.
572
573 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
574 size of <nn>. This works even on boxes that have no
575 highmem otherwise. This also works to reduce highmem
576 size on bigger boxes.
577
578 hisax= [HW,ISDN]
579 See Documentation/isdn/README.HiSax.
580
581 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
582
583 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
584
585 i8042.direct [HW] Put keyboard port into non-translated mode
586 i8042.dumbkbd [HW] Pretend that controlled can only read data from
587 keyboard and can not control its state
588 (Don't attempt to blink the leds)
589 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
Dmitry Torokhov945ef0d2005-09-04 01:42:00 -0500590 i8042.nokbd [HW] Don't check/create keyboard port
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 i8042.nomux [HW] Don't check presence of an active multiplexing
592 controller
593 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
594 controllers
595 i8042.panicblink=
596 [HW] Frequency with which keyboard LEDs should blink
597 when kernel panics (default is 0.5 sec)
598 i8042.reset [HW] Reset the controller during init and cleanup
599 i8042.unlock [HW] Unlock (ignore) the keylock
600
601 i810= [HW,DRM]
602
Dmitry Torokhove70c9d52005-06-25 14:54:25 -0700603 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
604 indicates that the driver is running on unsupported
605 hardware.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
607 does not match list of supported models.
608 i8k.power_status
609 [HW] Report power status in /proc/i8k
610 (disabled by default)
611 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
612 capability is set.
613
614 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
615 See Documentation/mca.txt.
616
617 icn= [HW,ISDN]
618 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
619
620 ide= [HW] (E)IDE subsystem
621 Format: ide=nodma or ide=doubler or ide=reverse
622 See Documentation/ide.txt.
623
624 ide?= [HW] (E)IDE subsystem
625 Format: ide?=noprobe or chipset specific parameters.
626 See Documentation/ide.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -0700627
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
629 See Documentation/ide.txt.
630
631 idle= [HW]
632 Format: idle=poll or idle=halt
Randy Dunlapa9913042005-10-23 12:57:11 -0700633
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 ihash_entries= [KNL]
635 Set number of hash buckets for inode cache.
636
637 in2000= [HW,SCSI]
638 See header of drivers/scsi/in2000.c.
639
640 init= [KNL]
641 Format: <full_path>
642 Run specified binary instead of /sbin/init as init
643 process.
644
645 initcall_debug [KNL] Trace initcalls as they are executed. Useful
646 for working out where the kernel is dying during
647 startup.
648
649 initrd= [BOOT] Specify the location of the initial ramdisk
650
651 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
652 Format: <irq>
653
Jesse Barnes2bd0fa32005-12-13 03:05:03 -0500654 combined_mode= [HW] control which driver uses IDE ports in combined
655 mode: legacy IDE driver, libata, or both
656 (in the libata case, libata.atapi_enabled=1 may be
657 useful as well). Note that using the ide or libata
658 options may affect your device naming (e.g. by
659 changing hdc to sdb).
660 Format: combined (default), ide, or libata
661
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 inttest= [IA64]
663
664 io7= [HW] IO7 for Marvel based alpha systems
665 See comment before marvel_specify_io7 in
666 arch/alpha/kernel/core_marvel.c.
667
668 ip= [IP_PNP]
669 See Documentation/nfsroot.txt.
670
671 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
672 See comment before ip2_setup() in drivers/char/ip2.c.
673
674 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
675 See header of drivers/scsi/ips.c.
676
Alan Cox200803d2005-06-28 20:45:18 -0700677 irqfixup [HW]
678 When an interrupt is not handled search all handlers
679 for it. Intended to get systems with badly broken
680 firmware running.
681
682 irqpoll [HW]
683 When an interrupt is not handled search all handlers
684 for it. Also check all handlers each timer
685 interrupt. Intended to get systems with badly broken
686 firmware running.
687
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 isapnp= [ISAPNP]
Randy Dunlapa9913042005-10-23 12:57:11 -0700689 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690
691 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
692 Format: <cpu number>,...,<cpu number>
693 This option can be used to specify one or more CPUs
694 to isolate from the general SMP balancing and scheduling
695 algorithms. The only way to move a process onto or off
696 an "isolated" CPU is via the CPU affinity syscalls.
697 <cpu number> begins at 0 and the maximum value is
698 "number of CPUs in system - 1".
699
700 This option is the preferred way to isolate CPUs. The
Randy Dunlapa9913042005-10-23 12:57:11 -0700701 alternative -- manually setting the CPU mask of all
702 tasks in the system -- can cause problems and
703 suboptimal load balancer performance.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704
705 isp16= [HW,CD]
706 Format: <io>,<irq>,<dma>,<setup>
707
Randy Dunlapa9913042005-10-23 12:57:11 -0700708 iucv= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709
710 js= [HW,JOY] Analog joystick
711 See Documentation/input/joystick.txt.
712
713 keepinitrd [HW,ARM]
714
Randy Dunlapa9913042005-10-23 12:57:11 -0700715 kstack=N [IA-32,X86-64] Print N words from the kernel stack
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 in oops dumps.
717
718 l2cr= [PPC]
719
Randy Dunlapa9913042005-10-23 12:57:11 -0700720 lapic [IA-32,APIC] Enable the local APIC even if BIOS
721 disabled it.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
723 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
724 Format: addr:<io>,irq:<irq>
725
Randy Dunlapa9913042005-10-23 12:57:11 -0700726 llsc*= [IA64] See function print_params() in
727 arch/ia64/sn/kernel/llsc4.c.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728
729 load_ramdisk= [RAM] List of ramdisks to load from floppy
730 See Documentation/ramdisk.txt.
731
Randy Dunlapa6b25b62006-01-14 13:21:19 -0800732 lockd.nlm_grace_period=P [NFS] Assign grace period.
733 Format: <integer>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734
Randy Dunlapa6b25b62006-01-14 13:21:19 -0800735 lockd.nlm_tcpport=N [NFS] Assign TCP port.
736 Format: <integer>
737
738 lockd.nlm_timeout=T [NFS] Assign timeout value.
739 Format: <integer>
740
741 lockd.nlm_udpport=M [NFS] Assign UDP port.
742 Format: <integer>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743
744 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
745 Format: <irq>
746
747 loglevel= All Kernel Messages with a loglevel smaller than the
748 console loglevel will be printed to the console. It can
749 also be changed with klogd or other programs. The
750 loglevels are defined as follows:
751
752 0 (KERN_EMERG) system is unusable
753 1 (KERN_ALERT) action must be taken immediately
754 2 (KERN_CRIT) critical conditions
755 3 (KERN_ERR) error conditions
756 4 (KERN_WARNING) warning conditions
757 5 (KERN_NOTICE) normal but significant condition
758 6 (KERN_INFO) informational
759 7 (KERN_DEBUG) debug-level messages
760
761 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
Randy Dunlapa9913042005-10-23 12:57:11 -0700762 Format: { n | nk | nM }
763 n must be a power of two. The default size
764 is set in the kernel config file.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765
766 lp=0 [LP] Specify parallel ports to use, e.g,
767 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
768 lp=reset first parallel port). 'lp=0' disables the
769 lp=auto printer driver. 'lp=reset' (which can be
770 specified in addition to the ports) causes
771 attached printers to be reset. Using
772 lp=port1,port2,... specifies the parallel ports
773 to associate lp devices with, starting with
774 lp0. A port specification may be 'none' to skip
775 that lp device, or a parport name such as
776 'parport0'. Specifying 'lp=auto' instead of a
777 port specification list means that device IDs
778 from each port should be examined, to see if
779 an IEEE 1284-compliant printer is attached; if
780 so, the driver will manage that printer.
781 See also header of drivers/char/lp.c.
782
783 lpj=n [KNL]
784 Sets loops_per_jiffy to given constant, thus avoiding
785 time-consuming boot-time autodetection (up to 250 ms per
786 CPU). 0 enables autodetection (default). To determine
787 the correct value for your kernel, boot with normal
788 autodetection and see what value is printed. Note that
789 on SMP systems the preset will be applied to all CPUs,
790 which is likely to cause problems if your CPUs need
791 significantly divergent settings. An incorrect value
792 will cause delays in the kernel to be wrong, leading to
793 unpredictable I/O errors and other breakage. Although
794 unlikely, in the extreme case this might damage your
795 hardware.
796
797 ltpc= [NET]
798 Format: <io>,<irq>,<dma>
799
Randy Dunlapa9913042005-10-23 12:57:11 -0700800 mac5380= [HW,SCSI] Format:
801 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802
Randy Dunlapa9913042005-10-23 12:57:11 -0700803 mac53c9x= [HW,SCSI] Format:
804 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805
Randy Dunlapa9913042005-10-23 12:57:11 -0700806 machvec= [IA64] Force the use of a particular machine-vector
807 (machvec) in a generic kernel.
808 Example: machvec=hpzx1_swiotlb
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809
Randy Dunlapa9913042005-10-23 12:57:11 -0700810 mad16= [HW,OSS] Format:
811 <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812
813 maui= [HW,OSS]
814 Format: <io>,<irq>
Randy Dunlapa9913042005-10-23 12:57:11 -0700815
816 max_loop= [LOOP] Maximum number of loopback devices that can
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 be mounted
818 Format: <1-256>
819
820 maxcpus= [SMP] Maximum number of processors that an SMP kernel
821 should make use of
822
Bob Picco2b2c3752005-06-29 18:00:00 -0700823 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
824 equal to this physical address is ignored.
825
Randy Dunlapa9913042005-10-23 12:57:11 -0700826 max_luns= [SCSI] Maximum number of LUNs to probe.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 Should be between 1 and 2^32-1.
828
829 max_report_luns=
Randy Dunlapa9913042005-10-23 12:57:11 -0700830 [SCSI] Maximum number of LUNs received.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 Should be between 1 and 16384.
832
833 mca-pentium [BUGS=IA-32]
834
835 mcatest= [IA-64]
836
837 mcd= [HW,CD]
838 Format: <port>,<irq>,<mitsumi_bug_93_wait>
839
840 mcdx= [HW,CD]
841
842 mce [IA-32] Machine Check Exception
843
844 md= [HW] RAID subsystems devices and level
845 See Documentation/md.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -0700846
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 mdacon= [MDA]
848 Format: <first>,<last>
849 Specifies range of consoles to be captured by the MDA.
Randy Dunlapa9913042005-10-23 12:57:11 -0700850
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
852 Amount of memory to be used when the kernel is not able
853 to see the whole system memory or for test.
854 [IA-32] Use together with memmap= to avoid physical
855 address space collisions. Without memmap= PCI devices
856 could be placed at addresses belonging to unused RAM.
857
858 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
859 memory.
860
akpm@osdl.org69cda7b2006-01-09 20:51:46 -0800861 memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 E820 memory map, as specified by the user.
863 Such memmap=exactmap lines can be constructed based on
864 BIOS output or other requirements. See the memmap=nn@ss
865 option description.
866
867 memmap=nn[KMG]@ss[KMG]
868 [KNL] Force usage of a specific region of memory
869 Region of memory to be used, from ss to ss+nn.
870
871 memmap=nn[KMG]#ss[KMG]
872 [KNL,ACPI] Mark specific memory as ACPI data.
873 Region of memory to be used, from ss to ss+nn.
874
875 memmap=nn[KMG]$ss[KMG]
876 [KNL,ACPI] Mark specific memory as reserved.
877 Region of memory to be used, from ss to ss+nn.
878
879 meye.*= [HW] Set MotionEye Camera parameters
880 See Documentation/video4linux/meye.txt.
881
882 mga= [HW,DRM]
883
akpm@osdl.org198e2f12006-01-12 01:05:30 -0800884 migration_cost=
885 [KNL,SMP] debug: override scheduler migration costs
886 Format: <level-1-usecs>,<level-2-usecs>,...
887 This debugging option can be used to override the
888 default scheduler migration cost matrix. The numbers
889 are indexed by 'CPU domain distance'.
890 E.g. migration_cost=1000,2000,3000 on an SMT NUMA
891 box will set up an intra-core migration cost of
892 1 msec, an inter-core migration cost of 2 msecs,
893 and an inter-node migration cost of 3 msecs.
894
895 WARNING: using the wrong values here can break
896 scheduler performance, so it's only for scheduler
897 development purposes, not production environments.
898
899 migration_debug=
900 [KNL,SMP] migration cost auto-detect verbosity
901 Format=<0|1|2>
902 If a system's migration matrix reported at bootup
903 seems erroneous then this option can be used to
904 increase verbosity of the detection process.
905 We default to 0 (no extra messages), 1 will print
906 some more information, and 2 will be really
907 verbose (probably only useful if you also have a
908 serial console attached to the system).
909
910 migration_factor=
911 [KNL,SMP] multiply/divide migration costs by a factor
912 Format=<percent>
913 This debug option can be used to proportionally
914 increase or decrease the auto-detected migration
915 costs for all entries of the migration matrix.
916 E.g. migration_factor=150 will increase migration
917 costs by 50%. (and thus the scheduler will be less
918 eager migrating cache-hot tasks)
919 migration_factor=80 will decrease migration costs
920 by 20%. (thus the scheduler will be more eager to
921 migrate tasks)
922
923 WARNING: using the wrong values here can break
924 scheduler performance, so it's only for scheduler
925 development purposes, not production environments.
926
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 mousedev.tap_time=
928 [MOUSE] Maximum time between finger touching and
929 leaving touchpad surface for touch to be considered
930 a tap and be reported as a left button click (for
931 touchpads working in absolute mode only).
932 Format: <msecs>
933 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
934 reporting absolute coordinates, such as tablets
935 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
936 reporting absolute coordinates, such as tablets
937
938 mpu401= [HW,OSS]
939 Format: <io>,<irq>
940
941 MTD_Partition= [MTD]
942 Format: <name>,<region-number>,<size>,<offset>
943
Randy Dunlapa9913042005-10-23 12:57:11 -0700944 MTD_Region= [MTD] Format:
945 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946
947 mtdparts= [MTD]
948 See drivers/mtd/cmdline.c.
949
950 mtouchusb.raw_coordinates=
Randy Dunlapa9913042005-10-23 12:57:11 -0700951 [HW] Make the MicroTouch USB driver use raw coordinates
952 ('y', default) or cooked coordinates ('n')
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953
954 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
955
956 NCR_D700= [HW,SCSI]
957 See header of drivers/scsi/NCR_D700.c.
958
959 ncr5380= [HW,SCSI]
960
961 ncr53c400= [HW,SCSI]
962
963 ncr53c400a= [HW,SCSI]
964
965 ncr53c406a= [HW,SCSI]
966
967 ncr53c8xx= [HW,SCSI]
968
969 netdev= [NET] Network devices parameters
970 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
971 Note that mem_start is often overloaded to mean
972 something different and driver-specific.
Randy Dunlapa9913042005-10-23 12:57:11 -0700973 This usage is only documented in each driver source
974 file if at all.
975
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 nfsaddrs= [NFS]
977 See Documentation/nfsroot.txt.
978
979 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
980 See Documentation/nfsroot.txt.
981
Trond Myklebusta72b4422006-01-03 09:55:41 +0100982 nfs.callback_tcpport=
983 [NFS] set the TCP port on which the NFSv4 callback
984 channel should listen.
985
Trond Myklebust58df0952006-01-03 09:55:57 +0100986 nfs.idmap_cache_timeout=
987 [NFS] set the maximum lifetime for idmapper cache
988 entries.
989
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
991
992 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
993 emulation library even if a 387 maths coprocessor
994 is present.
995
Randy Dunlapa9913042005-10-23 12:57:11 -0700996 noalign [KNL,ARM]
997
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998 noapic [SMP,APIC] Tells the kernel to not make use of any
999 IOAPICs that may be present in the system.
1000
1001 noasync [HW,M68K] Disables async and sync negotiation for
1002 all devices.
1003
1004 nobats [PPC] Do not use BATs for mapping kernel lowmem
1005 on "Classic" PPC cores.
1006
1007 nocache [ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001008
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1010
1011 noexec [IA-64]
1012
Randy Dunlapa9913042005-10-23 12:57:11 -07001013 noexec [IA-32,X86-64]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014 noexec=on: enable non-executable mappings (default)
1015 noexec=off: disable nn-executable mappings
1016
Chuck Ebbert4f886512006-03-23 02:59:34 -08001017 nofxsr [BUGS=IA-32] Disables x86 floating point extended
1018 register save and restore. The kernel will only save
1019 legacy floating-point registers on task switch.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020
1021 nohlt [BUGS=ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001022
Linus Torvalds1da177e2005-04-16 15:20:36 -07001023 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
1024 instruction doesn't work correctly and not to
1025 use it.
1026
1027 nohalt [IA-64] Tells the kernel not to use the power saving
1028 function PAL_HALT_LIGHT when idle. This increases
1029 power-consumption. On the positive side, it reduces
1030 interrupt wake-up latency, which may improve performance
1031 in certain environments such as networked servers or
1032 real-time systems.
1033
1034 noirqdebug [IA-32] Disables the code which attempts to detect and
1035 disable unhandled interrupt sources.
1036
1037 noisapnp [ISAPNP] Disables ISA PnP code.
1038
1039 noinitrd [RAM] Tells the kernel not to load any configured
1040 initial RAM disk.
1041
1042 nointroute [IA-64]
1043
1044 nolapic [IA-32,APIC] Do not enable or use the local APIC.
1045
1046 noltlbs [PPC] Do not use large page/tlb entries for kernel
1047 lowmem mapping on PPC40x.
1048
1049 nomce [IA-32] Machine Check Exception
1050
Horms312f1f02006-02-22 09:57:55 +09001051 nomca [IA-64] Disable machine check abort handling
1052
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053 noresidual [PPC] Don't use residual data on PReP machines.
1054
Randy Dunlapa9913042005-10-23 12:57:11 -07001055 noresume [SWSUSP] Disables resume and restores original swap
1056 space.
1057
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058 no-scroll [VGA] Disables scrollback.
1059 This is required for the Braillex ib80-piezo Braille
1060 reader made by F.H. Papenmeier (Germany).
1061
1062 nosbagart [IA-64]
1063
Chuck Ebbert4f886512006-03-23 02:59:34 -08001064 nosep [BUGS=IA-32] Disables x86 SYSENTER/SYSEXIT support.
1065
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
1067
1068 nosync [HW,M68K] Disables sync negotiation for all devices.
1069
1070 notsc [BUGS=IA-32] Disable Time Stamp Counter
1071
1072 nousb [USB] Disable the USB subsystem
1073
1074 nowb [ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001075
Dave Jonesa61c2d72006-01-07 23:18:19 +00001076 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1077
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 opl3= [HW,OSS]
1079 Format: <io>
1080
1081 opl3sa= [HW,OSS]
1082 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
1083
Randy Dunlapa9913042005-10-23 12:57:11 -07001084 opl3sa2= [HW,OSS] Format:
1085 <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
1086
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 oprofile.timer= [HW]
1088 Use timer interrupt instead of performance counters
1089
1090 optcd= [HW,CD]
1091 Format: <io>
1092
1093 osst= [HW,SCSI] SCSI Tape Driver
1094 Format: <buffer_size>,<write_threshold>
1095 See also Documentation/scsi/st.txt.
1096
1097 panic= [KNL] Kernel behaviour on panic
1098 Format: <timeout>
1099
1100 parkbd.port= [HW] Parallel port number the keyboard adapter is
1101 connected to, default is 0.
1102 Format: <parport#>
1103 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1104 0 for XT, 1 for AT (default is AT).
Randy Dunlapa9913042005-10-23 12:57:11 -07001105 Format: <mode>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106
Randy Dunlapa9913042005-10-23 12:57:11 -07001107 parport= [HW,PPT] Specify parallel ports. 0 disables.
1108 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1109 Use 'auto' to force the driver to use any
1110 IRQ/DMA settings detected (the default is to
1111 ignore detected IRQ/DMA settings because of
1112 possible conflicts). You can specify the base
1113 address, IRQ, and DMA settings; IRQ and DMA
1114 should be numbers, or 'auto' (for using detected
1115 settings on that particular port), or 'nofifo'
1116 (to avoid using a FIFO even if it is detected).
1117 Parallel ports are assigned in the order they
1118 are specified on the command line, starting
1119 with parport0.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001120
Randy Dunlapa9913042005-10-23 12:57:11 -07001121 parport_init_mode= [HW,PPT]
1122 Configure VIA parallel port to operate in
1123 a specific mode. This is necessary on Pegasos
1124 computer where firmware has no options for setting
1125 up parallel port mode and sets it to spp.
1126 Currently this function knows 686a and 8231 chips.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127 Format: [spp|ps2|epp|ecp|ecpepp]
1128
Randy Dunlapa9913042005-10-23 12:57:11 -07001129 pas2= [HW,OSS] Format:
1130 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1131
Linus Torvalds1da177e2005-04-16 15:20:36 -07001132 pas16= [HW,SCSI]
1133 See header of drivers/scsi/pas16.c.
1134
Andrew Mortondd287792006-03-23 03:00:57 -08001135 pause_on_oops=
1136 Halt all CPUs after the first oops has been printed for
1137 the specified number of seconds. This is to be used if
1138 your oopses keep scrolling off the screen.
1139
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140 pcbit= [HW,ISDN]
1141
1142 pcd. [PARIDE]
1143 See header of drivers/block/paride/pcd.c.
1144 See also Documentation/paride.txt.
1145
Randy Dunlapa9913042005-10-23 12:57:11 -07001146 pci=option[,option...] [PCI] various PCI subsystem options:
1147 off [IA-32] don't probe for the PCI bus
1148 bios [IA-32] force use of PCI BIOS, don't access
1149 the hardware directly. Use this if your machine
1150 has a non-standard PCI host bridge.
1151 nobios [IA-32] disallow use of PCI BIOS, only direct
1152 hardware access methods are allowed. Use this
1153 if you experience crashes upon bootup and you
1154 suspect they are caused by the BIOS.
1155 conf1 [IA-32] Force use of PCI Configuration
1156 Mechanism 1.
1157 conf2 [IA-32] Force use of PCI Configuration
1158 Mechanism 2.
Bjorn Helgaas61be6d62006-02-15 15:17:43 -08001159 nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
1160 Configuration
Matthew Wilcox309e57d2006-03-05 22:33:34 -07001161 nomsi [MSI] If the PCI_MSI kernel config parameter is
1162 enabled, this kernel boot option can be used to
1163 disable the use of MSI interrupts system-wide.
Randy Dunlapa9913042005-10-23 12:57:11 -07001164 nosort [IA-32] Don't sort PCI devices according to
1165 order given by the PCI BIOS. This sorting is
1166 done to get a device order compatible with
1167 older kernels.
1168 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1169 routing table. These calls are known to be buggy
1170 on several machines and they hang the machine
1171 when used, but on other computers it's the only
1172 way to get the interrupt routing table. Try
1173 this option if the kernel is unable to allocate
1174 IRQs or discover secondary PCI buses on your
1175 motherboard.
1176 rom [IA-32] Assign address space to expansion ROMs.
1177 Use with caution as certain devices share
1178 address decoders between ROMs and other
1179 resources.
1180 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be
1181 assigned automatically to PCI devices. You can
1182 make the kernel exclude IRQs of your ISA cards
1183 this way.
jayalk@intworks.biz120bb422005-03-21 20:20:42 -08001184 pirqaddr=0xAAAAA [IA-32] Specify the physical address
Randy Dunlapa9913042005-10-23 12:57:11 -07001185 of the PIRQ table (normally generated
1186 by the BIOS) if it is outside the
1187 F0000h-100000h range.
1188 lastbus=N [IA-32] Scan all buses thru bus #N. Can be
1189 useful if the kernel is unable to find your
1190 secondary buses and you want to tell it
1191 explicitly which ones they are.
1192 assign-busses [IA-32] Always assign all PCI bus
1193 numbers ourselves, overriding
1194 whatever the firmware may have done.
1195 usepirqmask [IA-32] Honor the possible IRQ mask stored
1196 in the BIOS $PIR table. This is needed on
1197 some systems with broken BIOSes, notably
1198 some HP Pavilion N5400 and Omnibook XE3
1199 notebooks. This will have no effect if ACPI
1200 IRQ routing is enabled.
1201 noacpi [IA-32] Do not use ACPI for IRQ routing
1202 or for PCI scanning.
1203 routeirq Do IRQ routing for all PCI devices.
1204 This is normally done in pci_enable_device(),
1205 so this option is a temporary workaround
1206 for broken drivers that don't call it.
1207 firmware [ARM] Do not re-enumerate the bus but instead
1208 just use the configuration from the
1209 bootloader. This is currently used on
1210 IXP2000 systems where the bus has to be
1211 configured a certain way for adjunct CPUs.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001212
1213 pcmv= [HW,PCMCIA] BadgePAD 4
1214
1215 pd. [PARIDE]
1216 See Documentation/paride.txt.
1217
1218 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1219 boot time.
1220 Format: { 0 | 1 }
1221 See arch/parisc/kernel/pdc_chassis.c
1222
1223 pf. [PARIDE]
1224 See Documentation/paride.txt.
1225
1226 pg. [PARIDE]
1227 See Documentation/paride.txt.
1228
1229 pirq= [SMP,APIC] Manual mp-table setup
1230 See Documentation/i386/IO-APIC.txt.
1231
1232 plip= [PPT,NET] Parallel port network link
1233 Format: { parport<nr> | timid | 0 }
1234 See also Documentation/parport.txt.
1235
1236 pnpacpi= [ACPI]
1237 { off }
1238
1239 pnpbios= [ISAPNP]
1240 { on | off | curr | res | no-curr | no-res }
1241
1242 pnp_reserve_irq=
1243 [ISAPNP] Exclude IRQs for the autoconfiguration
1244
1245 pnp_reserve_dma=
1246 [ISAPNP] Exclude DMAs for the autoconfiguration
1247
1248 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
Randy Dunlapa9913042005-10-23 12:57:11 -07001249 Ranges are in pairs (I/O port base and size).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250
1251 pnp_reserve_mem=
Randy Dunlapa9913042005-10-23 12:57:11 -07001252 [ISAPNP] Exclude memory regions for the
1253 autoconfiguration.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254 Ranges are in pairs (memory base and size).
1255
1256 profile= [KNL] Enable kernel profiling via /proc/profile
Randy Dunlapa9913042005-10-23 12:57:11 -07001257 Format: [schedule,]<number>
1258 Param: "schedule" - profile schedule points.
1259 Param: <number> - step/bucket size as a power of 2 for
1260 statistical time based profiling.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001261
Randy Dunlapa9913042005-10-23 12:57:11 -07001262 processor.max_cstate= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263 Limit processor to maximum C-state
1264 max_cstate=9 overrides any DMI blacklist limit.
1265
Len Brown41c0d862005-12-28 12:43:51 -05001266 processor.nocst [HW,ACPI]
1267 Ignore the _CST method to determine C-states,
1268 instead using the legacy FADT method
1269
Linus Torvalds1da177e2005-04-16 15:20:36 -07001270 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1271 before loading.
1272 See Documentation/ramdisk.txt.
1273
Randy Dunlapa9913042005-10-23 12:57:11 -07001274 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1275 probe for; one of (bare|imps|exps|lifebook|any).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1277 per second.
Randy Dunlapa9913042005-10-23 12:57:11 -07001278 psmouse.resetafter= [HW,MOUSE]
1279 Try to reset the device after so many bad packets
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280 (0 = never).
1281 psmouse.resolution=
1282 [HW,MOUSE] Set desired mouse resolution, in dpi.
1283 psmouse.smartscroll=
Randy Dunlapa9913042005-10-23 12:57:11 -07001284 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285 0 = disabled, 1 = enabled (default).
1286
1287 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
Randy Dunlapa9913042005-10-23 12:57:11 -07001288 Format:
1289 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290
1291 pt. [PARIDE]
1292 See Documentation/paride.txt.
1293
1294 quiet= [KNL] Disable log messages
Randy Dunlapa9913042005-10-23 12:57:11 -07001295
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 r128= [HW,DRM]
1297
1298 raid= [HW,RAID]
1299 See Documentation/md.txt.
1300
1301 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1302 See Documentation/ramdisk.txt.
1303
Randy Dunlapa9913042005-10-23 12:57:11 -07001304 ramdisk_blocksize= [RAM]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305 See Documentation/ramdisk.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -07001306
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1308 New name for the ramdisk parameter.
1309 See Documentation/ramdisk.txt.
1310
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001311 rcu.blimit= [KNL,BOOT] Set maximum number of finished
1312 RCU callbacks to process in one batch.
1313
1314 rcu.qhimark= [KNL,BOOT] Set threshold of queued
1315 RCU callbacks over which batch limiting is disabled.
1316
1317 rcu.qlowmark= [KNL,BOOT] Set threshold of queued
1318 RCU callbacks below which batch limiting is re-enabled.
1319
1320 rcu.rsinterval= [KNL,BOOT,SMP] Set the number of additional
1321 RCU callbacks to queued before forcing reschedule
1322 on all cpus.
1323
Olof Johanssonffdfc402005-09-06 15:17:19 -07001324 rdinit= [KNL]
1325 Format: <full_path>
1326 Run specified binary instead of /init from the ramdisk,
1327 used for early userspace startup. See initrd.
1328
Linus Torvalds1da177e2005-04-16 15:20:36 -07001329 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1330 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1331 See arch/*/kernel/reboot.c.
1332
1333 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1334
Randy Dunlapa9913042005-10-23 12:57:11 -07001335 resume= [SWSUSP]
1336 Specify the partition device for software suspend
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337
1338 rhash_entries= [KNL,NET]
1339 Set number of hash buckets for route cache
1340
1341 riscom8= [HW,SERIAL]
1342 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1343
1344 ro [KNL] Mount root device read-only on boot
1345
1346 root= [KNL] Root filesystem
1347
1348 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1349 mount the root filesystem
1350
1351 rootflags= [KNL] Set root filesystem mount option string
1352
1353 rootfstype= [KNL] Set root filesystem type
1354
1355 rw [KNL] Mount root device read-write on boot
1356
1357 S [KNL] Run init in single mode
1358
1359 sa1100ir [NET]
1360 See drivers/net/irda/sa1100_ir.c.
1361
1362 sb= [HW,OSS]
1363 Format: <io>,<irq>,<dma>,<dma2>
1364
1365 sbni= [NET] Granch SBNI12 leased line adapter
Randy Dunlapa9913042005-10-23 12:57:11 -07001366
Linus Torvalds1da177e2005-04-16 15:20:36 -07001367 sbpcd= [HW,CD] Soundblaster CD adapter
1368 Format: <io>,<type>
1369 See a comment before function sbpcd_setup() in
1370 drivers/cdrom/sbpcd.c.
1371
1372 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1373 Format: <io>[,<timeout>[,<isapnp>]]
1374
1375 scsi_debug_*= [SCSI]
1376 See drivers/scsi/scsi_debug.c.
1377
1378 scsi_default_dev_flags=
1379 [SCSI] SCSI default device flags
1380 Format: <integer>
1381
1382 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1383 Format: <vendor>:<model>:<flags>
1384 (flags are integer value)
1385
1386 scsi_logging= [SCSI]
1387
1388 selinux [SELINUX] Disable or enable SELinux at boot time.
1389 Format: { "0" | "1" }
1390 See security/selinux/Kconfig help text.
1391 0 -- disable.
1392 1 -- enable.
1393 Default value is set via kernel config option.
1394 If enabled at boot time, /selinux/disable can be used
1395 later to disable prior to initial policy load.
1396
1397 serialnumber [BUGS=IA-32]
1398
Randy Dunlapa9913042005-10-23 12:57:11 -07001399 sg_def_reserved_size= [SCSI]
1400
Linus Torvalds1da177e2005-04-16 15:20:36 -07001401 sgalaxy= [HW,OSS]
1402 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1403
1404 shapers= [NET]
1405 Maximal number of shapers.
Randy Dunlapa9913042005-10-23 12:57:11 -07001406
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407 sim710= [SCSI,HW]
1408 See header of drivers/scsi/sim710.c.
1409
1410 simeth= [IA-64]
1411 simscsi=
Randy Dunlapa9913042005-10-23 12:57:11 -07001412
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 sjcd= [HW,CD]
1414 Format: <io>,<irq>,<dma>
1415 See header of drivers/cdrom/sjcd.c.
1416
1417 slram= [HW,MTD]
1418
1419 smart2= [HW]
1420 Format: <io1>[,<io2>[,...,<io8>]]
1421
1422 snd-ad1816a= [HW,ALSA]
1423
1424 snd-ad1848= [HW,ALSA]
1425
1426 snd-ali5451= [HW,ALSA]
1427
1428 snd-als100= [HW,ALSA]
1429
1430 snd-als4000= [HW,ALSA]
1431
1432 snd-azt2320= [HW,ALSA]
1433
1434 snd-cmi8330= [HW,ALSA]
1435
1436 snd-cmipci= [HW,ALSA]
1437
1438 snd-cs4231= [HW,ALSA]
1439
1440 snd-cs4232= [HW,ALSA]
1441
1442 snd-cs4236= [HW,ALSA]
1443
1444 snd-cs4281= [HW,ALSA]
1445
1446 snd-cs46xx= [HW,ALSA]
1447
1448 snd-dt019x= [HW,ALSA]
1449
1450 snd-dummy= [HW,ALSA]
1451
1452 snd-emu10k1= [HW,ALSA]
1453
1454 snd-ens1370= [HW,ALSA]
1455
1456 snd-ens1371= [HW,ALSA]
1457
1458 snd-es968= [HW,ALSA]
1459
1460 snd-es1688= [HW,ALSA]
1461
1462 snd-es18xx= [HW,ALSA]
1463
1464 snd-es1938= [HW,ALSA]
1465
1466 snd-es1968= [HW,ALSA]
1467
1468 snd-fm801= [HW,ALSA]
1469
1470 snd-gusclassic= [HW,ALSA]
1471
1472 snd-gusextreme= [HW,ALSA]
1473
1474 snd-gusmax= [HW,ALSA]
1475
1476 snd-hdsp= [HW,ALSA]
1477
1478 snd-ice1712= [HW,ALSA]
1479
1480 snd-intel8x0= [HW,ALSA]
1481
1482 snd-interwave= [HW,ALSA]
1483
1484 snd-interwave-stb=
1485 [HW,ALSA]
1486
1487 snd-korg1212= [HW,ALSA]
1488
1489 snd-maestro3= [HW,ALSA]
1490
1491 snd-mpu401= [HW,ALSA]
1492
1493 snd-mtpav= [HW,ALSA]
1494
1495 snd-nm256= [HW,ALSA]
1496
1497 snd-opl3sa2= [HW,ALSA]
1498
1499 snd-opti92x-ad1848=
1500 [HW,ALSA]
1501
1502 snd-opti92x-cs4231=
1503 [HW,ALSA]
1504
1505 snd-opti93x= [HW,ALSA]
1506
1507 snd-pmac= [HW,ALSA]
1508
1509 snd-rme32= [HW,ALSA]
1510
1511 snd-rme96= [HW,ALSA]
1512
1513 snd-rme9652= [HW,ALSA]
1514
1515 snd-sb8= [HW,ALSA]
1516
1517 snd-sb16= [HW,ALSA]
1518
1519 snd-sbawe= [HW,ALSA]
1520
1521 snd-serial= [HW,ALSA]
1522
1523 snd-sgalaxy= [HW,ALSA]
1524
1525 snd-sonicvibes= [HW,ALSA]
1526
1527 snd-sun-amd7930=
1528 [HW,ALSA]
1529
1530 snd-sun-cs4231= [HW,ALSA]
1531
1532 snd-trident= [HW,ALSA]
1533
1534 snd-usb-audio= [HW,ALSA,USB]
1535
1536 snd-via82xx= [HW,ALSA]
1537
1538 snd-virmidi= [HW,ALSA]
1539
1540 snd-wavefront= [HW,ALSA]
1541
1542 snd-ymfpci= [HW,ALSA]
Randy Dunlapa9913042005-10-23 12:57:11 -07001543
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544 sonicvibes= [HW,OSS]
1545 Format: <reverb>
Randy Dunlapa9913042005-10-23 12:57:11 -07001546
Linus Torvalds1da177e2005-04-16 15:20:36 -07001547 sonycd535= [HW,CD]
1548 Format: <io>[,<irq>]
1549
1550 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1551 See Documentation/sonypi.txt
1552
1553 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1554 See Documentation/specialix.txt.
1555
1556 spia_io_base= [HW,MTD]
1557 spia_fio_base=
1558 spia_pedr=
1559 spia_peddr=
1560
1561 sscape= [HW,OSS]
1562 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
Randy Dunlapa9913042005-10-23 12:57:11 -07001563
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1565 See Documentation/scsi/st.txt.
1566
1567 st0x= [HW,SCSI]
1568 See header of drivers/scsi/seagate.c.
1569
1570 sti= [PARISC,HW]
1571 Format: <num>
1572 Set the STI (builtin display/keyboard on the HP-PARISC
1573 machines) console (graphic card) which should be used
1574 as the initial boot-console.
1575 See also comment in drivers/video/console/sticore.c.
1576
1577 sti_font= [HW]
1578 See comment in drivers/video/console/sticore.c.
1579
1580 stifb= [HW]
1581 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1582
Linus Torvalds1da177e2005-04-16 15:20:36 -07001583 swiotlb= [IA-64] Number of I/O TLB slabs
Randy Dunlapa9913042005-10-23 12:57:11 -07001584
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585 switches= [HW,M68k]
1586
1587 sym53c416= [HW,SCSI]
1588 See header of drivers/scsi/sym53c416.c.
1589
1590 t128= [HW,SCSI]
1591 See header of drivers/scsi/t128.c.
1592
1593 tdfx= [HW,DRM]
1594
1595 thash_entries= [KNL,NET]
1596 Set number of hash buckets for TCP connection
1597
1598 time Show timing data prefixed to each printk message line
1599
1600 tipar.timeout= [HW,PPT]
1601 Set communications timeout in tenths of a second
1602 (default 15).
1603
1604 tipar.delay= [HW,PPT]
1605 Set inter-bit delay in microseconds (default 10).
1606
1607 tmc8xx= [HW,SCSI]
1608 See header of drivers/scsi/seagate.c.
1609
1610 tmscsim= [HW,SCSI]
1611 See comment before function dc390_setup() in
1612 drivers/scsi/tmscsim.c.
1613
1614 tp720= [HW,PS2]
1615
1616 trix= [HW,OSS] MediaTrix AudioTrix Pro
Randy Dunlapa9913042005-10-23 12:57:11 -07001617 Format:
1618 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1619
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 tsdev.xres= [TS] Horizontal screen resolution.
1621 tsdev.yres= [TS] Vertical screen resolution.
1622
Randy Dunlapa9913042005-10-23 12:57:11 -07001623 turbografx.map[2|3]= [HW,JOY]
1624 TurboGraFX parallel port interface
1625 Format:
1626 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001627 See also Documentation/input/joystick-parport.txt
1628
1629 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1630 See header of drivers/scsi/u14-34f.c.
1631
1632 uart401= [HW,OSS]
1633 Format: <io>,<irq>
1634
1635 uart6850= [HW,OSS]
1636 Format: <io>,<irq>
1637
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 usbhid.mousepoll=
1639 [USBHID] The interval which mice are to be polled at.
Randy Dunlapa9913042005-10-23 12:57:11 -07001640
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641 video= [FB] Frame buffer configuration
1642 See Documentation/fb/modedb.txt.
1643
1644 vga= [BOOT,IA-32] Select a particular video mode
Randy Dunlapa9913042005-10-23 12:57:11 -07001645 See Documentation/i386/boot.txt and
1646 Documentation/svga.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647 Use vga=ask for menu.
1648 This is actually a boot loader parameter; the value is
1649 passed to the kernel using a special protocol.
1650
Randy Dunlapa9913042005-10-23 12:57:11 -07001651 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
Linus Torvalds1da177e2005-04-16 15:20:36 -07001652 size of <nn>. This can be used to increase the
1653 minimum size (128MB on x86). It can also be used to
1654 decrease the size and leave more room for directly
1655 mapped kernel RAM.
1656
1657 vmhalt= [KNL,S390]
1658
Randy Dunlapa9913042005-10-23 12:57:11 -07001659 vmpoff= [KNL,S390]
1660
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661 waveartist= [HW,OSS]
1662 Format: <io>,<irq>,<dma>,<dma2>
Randy Dunlapa9913042005-10-23 12:57:11 -07001663
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 wd33c93= [HW,SCSI]
1665 See header of drivers/scsi/wd33c93.c.
1666
1667 wd7000= [HW,SCSI]
1668 See header of drivers/scsi/wd7000.c.
1669
1670 wdt= [WDT] Watchdog
1671 See Documentation/watchdog/watchdog.txt.
1672
1673 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1674 xd_geo= See header of drivers/block/xd.c.
1675
1676 xirc2ps_cs= [NET,PCMCIA]
Randy Dunlapa9913042005-10-23 12:57:11 -07001677 Format:
1678 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001679
Andi Kleena62eaf12006-02-16 23:41:58 +01001680 norandmaps Don't use address space randomization
1681 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
1682
Linus Torvalds1da177e2005-04-16 15:20:36 -07001683
Randy Dunlapa9913042005-10-23 12:57:11 -07001684______________________________________________________________________
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685Changelog:
1686
Randy Dunlapa9913042005-10-23 12:57:11 -070016872000-06-?? Mr. Unknown
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688 The last known update (for 2.4.0) - the changelog was not kept before.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689
Randy Dunlapa9913042005-10-23 12:57:11 -070016902002-11-24 Petr Baudis <pasky@ucw.cz>
1691 Randy Dunlap <randy.dunlap@verizon.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001692 Update for 2.5.49, description for most of the options introduced,
1693 references to other documentation (C files, READMEs, ..), added S390,
1694 PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
1695 reformatting.
Randy Dunlapa9913042005-10-23 12:57:11 -07001696
16972005-10-19 Randy Dunlap <rdunlap@xenotime.net>
1698 Lots of typos, whitespace, some reformatting.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001699
1700TODO:
1701
1702 Add documentation for ALSA options.
1703 Add more DRM drivers.