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Mauro Carvalho Chehabe53dd082007-09-15 07:38:47 -03001 Kernel Parameters
2 ~~~~~~~~~~~~~~~~~
Linus Torvalds1da177e2005-04-16 15:20:36 -07003
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
Stefan Richtera901ebb2006-04-01 01:43:18 +020020This document may not be entirely up to date and comprehensive. The command
21"modinfo -p ${modulename}" shows a current list of all parameters of a loadable
22module. Loadable modules, after being loaded into the running kernel, also
23reveal their parameters in /sys/module/${modulename}/parameters/. Some of these
24parameters may be changed at runtime by the command
25"echo -n ${value} > /sys/module/${modulename}/parameters/${parm}".
26
Stefan Richter6585fa82006-04-01 01:44:30 +020027The parameters listed below are only valid if certain kernel build options were
28enabled and if respective hardware is present. The text in square brackets at
29the beginning of each description states the restrictions within which a
30parameter is applicable:
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32 ACPI ACPI support is enabled.
Chuck Ebbertc99c1082007-07-27 10:46:20 +100033 AGP AGP (Accelerated Graphics Port) is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 ALSA ALSA sound support is enabled.
35 APIC APIC support is enabled.
36 APM Advanced Power Management support is enabled.
Haavard Skinnemoene7ba1762007-10-10 14:58:29 +020037 AVR32 AVR32 architecture is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 AX25 Appropriate AX.25 support is enabled.
Robin Getz0ae53642007-10-09 17:24:49 +080039 BLACKFIN Blackfin architecture is enabled.
Randy Dunlapa9913042005-10-23 12:57:11 -070040 DRM Direct Rendering Management support is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
42 EFI EFI Partitioning (GPT) is enabled
43 EIDE EIDE/ATAPI support is enabled.
44 FB The frame buffer device is enabled.
45 HW Appropriate hardware is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070046 IA-64 IA-64 architecture is enabled.
47 IOSCHED More than one I/O scheduler is enabled.
Adrian Bunk41e2e8b2005-07-12 13:58:33 -070048 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 ISAPNP ISA PnP code is enabled.
50 ISDN Appropriate ISDN support is enabled.
51 JOY Appropriate joystick support is enabled.
Kristen Carlson Accardi11ef6972006-09-28 11:29:01 -070052 LIBATA Libata driver is enabled
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 LP Printer support is enabled.
54 LOOP Loopback device support is enabled.
55 M68k M68k architecture is enabled.
56 These options have more detailed description inside of
57 Documentation/m68k/kernel-options.txt.
58 MCA MCA bus support is enabled.
59 MDA MDA console support is enabled.
60 MOUSE Appropriate mouse support is enabled.
Matthew Wilcox309e57d2006-03-05 22:33:34 -070061 MSI Message Signaled Interrupts (PCI).
Randy Dunlapc8facbb2007-07-31 00:37:40 -070062 MTD MTD (Memory Technology Device) support is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 NET Appropriate network support is enabled.
64 NUMA NUMA support is enabled.
john stultz734efb42006-06-26 00:25:05 -070065 GENERIC_TIME The generic timeofday code is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 NFS Appropriate NFS support is enabled.
67 OSS OSS sound support is enabled.
Randy Dunlapc8facbb2007-07-31 00:37:40 -070068 PV_OPS A paravirtualized kernel is enabled.
69 PARIDE The ParIDE (parallel port IDE) subsystem is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 PARISC The PA-RISC architecture is enabled.
71 PCI PCI bus support is enabled.
Randy Dunlap7f785762007-10-05 13:17:58 -070072 PCIE PCI Express support is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 PCMCIA The PCMCIA subsystem is enabled.
74 PNP Plug & Play support is enabled.
75 PPC PowerPC architecture is enabled.
76 PPT Parallel port support is enabled.
77 PS2 Appropriate PS/2 support is enabled.
78 RAM RAM disk support is enabled.
James Morris20510f22007-10-16 23:31:32 -070079 ROOTPLUG The example Root Plug LSM is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 S390 S390 architecture is enabled.
81 SCSI Appropriate SCSI support is enabled.
82 A lot of drivers has their options described inside of
83 Documentation/scsi/.
James Morris20510f22007-10-16 23:31:32 -070084 SECURITY Different security models are enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 SELINUX SELinux support is enabled.
86 SERIAL Serial support is enabled.
Paul Mundte523d932007-02-28 18:30:01 +090087 SH SuperH architecture is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 SMP The kernel is an SMP kernel.
89 SPARC Sparc architecture is enabled.
Randy Dunlapa9913042005-10-23 12:57:11 -070090 SWSUSP Software suspend is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 TS Appropriate touchscreen support is enabled.
92 USB USB support is enabled.
93 USBHID USB Human Interface Device support is enabled.
94 V4L Video For Linux support is enabled.
95 VGA The VGA console has been enabled.
96 VT Virtual terminal support is enabled.
97 WDT Watchdog support is enabled.
98 XT IBM PC/XT MFM hard disk support is enabled.
Alan Coxcd4f0ef2007-07-31 00:37:59 -070099 X86-32 X86-32, aka i386 architecture is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 X86-64 X86-64 architecture is enabled.
101 More X86-64 boot options can be found in
102 Documentation/x86_64/boot-options.txt .
103
104In addition, the following text indicates that the option:
105
106 BUGS= Relates to possible processor bugs on the said processor.
107 KNL Is a kernel start-up parameter.
108 BOOT Is a boot loader parameter.
109
110Parameters denoted with BOOT are actually interpreted by the boot
111loader, and have no meaning to the kernel directly.
112Do not modify the syntax of boot loader parameters without extreme
113need or coordination with <Documentation/i386/boot.txt>.
114
Karsten Weiss55588702007-02-13 13:26:21 +0100115There are also arch-specific kernel-parameters not documented here.
116See for example <Documentation/x86_64/boot-options.txt>.
117
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
119a trailing = on the name of any parameter states that that parameter will
120be entered as an environment variable, whereas its absence indicates that
121it will appear as a kernel argument readable via /proc/cmdline by programs
122running once the system is up.
123
jens m. noedler9c4751f2006-09-29 02:00:27 -0700124The number of kernel parameters is not limited, but the length of the
125complete command line (parameters including spaces etc.) is limited to
126a fixed number of characters. This limit depends on the architecture
127and is between 256 and 4096 characters. It is defined in the file
128./include/asm/setup.h as COMMAND_LINE_SIZE.
129
130
Bernhard Walle03d926f2007-03-06 02:29:44 -0800131 acpi= [HW,ACPI,X86-64,i386]
132 Advanced Configuration and Power Interface
Randy Dunlapa9913042005-10-23 12:57:11 -0700133 Format: { force | off | ht | strict | noirq }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 force -- enable ACPI if default was off
135 off -- disable ACPI if default was on
136 noirq -- do not use ACPI for IRQ routing
137 ht -- run only enough ACPI to enable Hyper Threading
Randy Dunlapa9913042005-10-23 12:57:11 -0700138 strict -- Be less tolerant of platforms that are not
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 strictly ACPI specification compliant.
140
Randy Dunlap53471122008-03-12 18:10:51 -0400141 See also Documentation/power/pm.txt, pci=noacpi
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
Len Browna1fdcc02007-03-11 03:26:14 -0400143 acpi_apic_instance= [ACPI, IOAPIC]
144 Format: <int>
145 2: use 2nd APIC table, if available
146 1,0: use 1st APIC table
Len Brown4e381a42007-03-30 14:16:10 -0400147 default: 0
Len Browna1fdcc02007-03-11 03:26:14 -0400148
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 acpi_sleep= [HW,ACPI] Sleep options
Pavel Machek23b168d2008-02-05 19:27:12 +0100150 Format: { s3_bios, s3_mode, s3_beep }
151 See Documentation/power/video.txt for s3_bios and s3_mode.
152 s3_beep is for debugging; it makes the PC's speaker beep
153 as soon as the kernel's real-mode entry point is called.
Randy Dunlapa9913042005-10-23 12:57:11 -0700154
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Randy Dunlapa9913042005-10-23 12:57:11 -0700156 Format: { level | edge | high | low }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157
Randy Dunlapa9913042005-10-23 12:57:11 -0700158 acpi_irq_balance [HW,ACPI]
159 ACPI will balance active IRQs
160 default in APIC mode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161
Randy Dunlapa9913042005-10-23 12:57:11 -0700162 acpi_irq_nobalance [HW,ACPI]
163 ACPI will not move active IRQs (default)
164 default in PIC mode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
Randy Dunlapa9913042005-10-23 12:57:11 -0700166 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
167 use by PCI
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 Format: <irq>,<irq>...
169
Randy Dunlapa9913042005-10-23 12:57:11 -0700170 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 Format: <irq>,<irq>...
172
Len Brown67effe82007-07-26 00:50:06 -0400173 acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
174
Len Browna1f9e652006-01-25 23:47:36 -0500175 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
176 Format: To spoof as Windows 98: ="Microsoft Windows"
177
Len Brownae00d812007-05-29 18:43:33 -0400178 acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
179 acpi_osi="string1" # add string1 -- only one string
180 acpi_osi="!string2" # remove built-in string2
181 acpi_osi= # disable all strings
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
183 acpi_serialize [HW,ACPI] force serialization of AML methods
184
185 acpi_skip_timer_override [HW,ACPI]
186 Recognize and ignore IRQ0/pin2 Interrupt Override.
187 For broken nForce2 BIOS resulting in XT-PIC timer.
Andi Kleenfa18f472006-11-14 16:57:46 +0100188 acpi_use_timer_override [HW,ACPI}
189 Use timer override. For some broken Nvidia NF5 boards
190 that require a timer override, but don't have
191 HPET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192
Zhang Ruif9891062007-04-24 13:53:22 +0800193 acpi.debug_layer= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 Format: <int>
Randy Dunlapa9913042005-10-23 12:57:11 -0700195 Each bit of the <int> indicates an ACPI debug layer,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 1: enable, 0: disable. It is useful for boot time
197 debugging. After system has booted up, it can be set
Zhang Ruif9891062007-04-24 13:53:22 +0800198 via /sys/module/acpi/parameters/debug_layer.
199 CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
200 Available bits (add the numbers together) to enable debug output
201 for specific parts of the ACPI subsystem:
202 0x01 utilities 0x02 hardware 0x04 events 0x08 tables
203 0x10 namespace 0x20 parser 0x40 dispatcher
204 0x80 executer 0x100 resources 0x200 acpica debugger
205 0x400 os services 0x800 acpica disassembler.
206 The number can be in decimal or prefixed with 0x in hex.
207 Warning: Many of these options can produce a lot of
208 output and make your system unusable. Be very careful.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
Zhang Ruif9891062007-04-24 13:53:22 +0800210 acpi.debug_level= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 Format: <int>
Randy Dunlapa9913042005-10-23 12:57:11 -0700212 Each bit of the <int> indicates an ACPI debug level,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 1: enable, 0: disable. It is useful for boot time
214 debugging. After system has booted up, it can be set
Zhang Ruif9891062007-04-24 13:53:22 +0800215 via /sys/module/acpi/parameters/debug_level.
216 CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
217 Available bits (add the numbers together) to enable different
218 debug output levels of the ACPI subsystem:
219 0x01 error 0x02 warn 0x04 init 0x08 debug object
220 0x10 info 0x20 init names 0x40 parse 0x80 load
221 0x100 dispatch 0x200 execute 0x400 names 0x800 operation region
222 0x1000 bfield 0x2000 tables 0x4000 values 0x8000 objects
223 0x10000 resources 0x20000 user requests 0x40000 package.
224 The number can be in decimal or prefixed with 0x in hex.
225 Warning: Many of these options can produce a lot of
226 output and make your system unusable. Be very careful.
227
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700228 acpi_pm_good [X86-32,X86-64]
john stultz5d0cf412006-06-26 00:25:12 -0700229 Override the pmtimer bug detection: force the kernel
230 to assume that this machine's pmtimer latches its value
231 and always returns good values.
232
Chuck Ebbertc99c1082007-07-27 10:46:20 +1000233 agp= [AGP]
234 { off | try_unsupported }
235 off: disable AGP support
236 try_unsupported: try to drive unsupported chipsets
237 (may crash computer or cause data corruption)
238
Chuck Ebbert66759a02005-09-12 18:49:25 +0200239 enable_timer_pin_1 [i386,x86-64]
240 Enable PIN 1 of APIC timer
Randy Dunlapa9913042005-10-23 12:57:11 -0700241 Can be useful to work around chipset bugs
242 (in particular on some ATI chipsets).
Chuck Ebbert66759a02005-09-12 18:49:25 +0200243 The kernel tries to set a reasonable default.
244
245 disable_timer_pin_1 [i386,x86-64]
246 Disable PIN 1 of APIC timer
247 Can be useful to work around chipset bugs.
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 ad1848= [HW,OSS]
250 Format: <io>,<irq>,<dma>,<dma2>,<type>
251
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 advansys= [HW,SCSI]
253 See header of drivers/scsi/advansys.c.
254
255 advwdt= [HW,WDT] Advantech WDT
256 Format: <iostart>,<iostop>
257
258 aedsp16= [HW,OSS] Audio Excel DSP 16
259 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
260 See also header of sound/oss/aedsp16.c.
Randy Dunlapa9913042005-10-23 12:57:11 -0700261
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 aha152x= [HW,SCSI]
263 See Documentation/scsi/aha152x.txt.
264
265 aha1542= [HW,SCSI]
266 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
267
268 aic7xxx= [HW,SCSI]
269 See Documentation/scsi/aic7xxx.txt.
270
271 aic79xx= [HW,SCSI]
272 See Documentation/scsi/aic79xx.txt.
273
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 amijoy.map= [HW,JOY] Amiga joystick support
275 Map of devices attached to JOY0DAT and JOY1DAT
276 Format: <a>,<b>
277 See also Documentation/kernel/input/joystick.txt
278
279 analog.map= [HW,JOY] Analog joystick and gamepad support
280 Specifies type or capabilities of an analog joystick
281 connected to one of 16 gameports
282 Format: <type1>,<type2>,..<type16>
283
Randy Dunlapa9913042005-10-23 12:57:11 -0700284 apc= [HW,SPARC]
285 Power management functions (SPARCstation-4/5 + deriv.)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 Format: noidle
287 Disable APC CPU standby support. SPARCstation-Fox does
288 not play well with APC CPU idle - disable it if you have
289 APC and your system crashes randomly.
290
Randy Dunlapc8facbb2007-07-31 00:37:40 -0700291 apic= [APIC,i386] Advanced Programmable Interrupt Controller
292 Change the output verbosity whilst booting
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 Format: { quiet (default) | verbose | debug }
294 Change the amount of debugging information output
295 when initialising the APIC and IO-APIC components.
Randy Dunlapa9913042005-10-23 12:57:11 -0700296
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 apm= [APM] Advanced Power Management
298 See header of arch/i386/kernel/apm.c.
299
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
301 Format: <io>,<irq>,<nodeID>
302
303 ataflop= [HW,M68k]
304
305 atarimouse= [HW,MOUSE] Atari Mouse
306
307 atascsi= [HW,SCSI] Atari SCSI
308
309 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
310 EzKey and similar keyboards
311
312 atkbd.reset= [HW] Reset keyboard during initialization
313
Randy Dunlapa9913042005-10-23 12:57:11 -0700314 atkbd.set= [HW] Select keyboard code set
315 Format: <int> (2 = AT (default), 3 = PS/2)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316
317 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
318 keyboards
319
320 atkbd.softraw= [HW] Choose between synthetic and real raw mode
321 Format: <bool> (0 = real, 1 = synthetic (default))
Randy Dunlapa9913042005-10-23 12:57:11 -0700322
323 atkbd.softrepeat= [HW]
324 Use software keyboard repeat
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
326 autotest [IA64]
327
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 baycom_epp= [HW,AX25]
329 Format: <io>,<mode>
Randy Dunlapa9913042005-10-23 12:57:11 -0700330
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
332 Format: <io>,<mode>
333 See header of drivers/net/hamradio/baycom_par.c.
334
Randy Dunlapa9913042005-10-23 12:57:11 -0700335 baycom_ser_fdx= [HW,AX25]
336 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 Format: <io>,<irq>,<mode>[,<baud>]
338 See header of drivers/net/hamradio/baycom_ser_fdx.c.
339
Randy Dunlapa9913042005-10-23 12:57:11 -0700340 baycom_ser_hdx= [HW,AX25]
341 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 Format: <io>,<irq>,<mode>
343 See header of drivers/net/hamradio/baycom_ser_hdx.c.
344
Randy Dunlapbfe8df32007-10-16 01:23:46 -0700345 boot_delay= Milliseconds to delay each printk during boot.
346 Values larger than 10 seconds (10000) are changed to
347 no delay (0).
348 Format: integer
349
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
Randy Dunlapa9913042005-10-23 12:57:11 -0700351 bttv.radio= Most important insmod options are available as
352 kernel args too.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
354 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
355
356 BusLogic= [HW,SCSI]
357 See drivers/scsi/BusLogic.c, comment before function
358 BusLogic_ParseDriverOptions().
359
360 c101= [NET] Moxa C101 synchronous serial card
361
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700362 cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 Sometimes CPU hardware bugs make them report the cache
364 size incorrectly. The kernel will attempt work arounds
365 to fix known problems, but for some CPUs it is not
366 possible to determine what the correct size should be.
367 This option provides an override for these situations.
368
Ahmed S. Darwish076c54c2008-03-06 18:09:10 +0200369 security= [SECURITY] Choose a security module to enable at boot.
370 If this boot parameter is not specified, only the first
371 security module asking for security registration will be
372 loaded. An invalid security module name will be treated
373 as if no module has been chosen.
374
James Morris20510f22007-10-16 23:31:32 -0700375 capability.disable=
376 [SECURITY] Disable capabilities. This would normally
377 be used only if an alternative security model is to be
378 configured. Potentially dangerous and should only be
379 used if you are entirely sure of the consequences.
380
Sebastian Ott14ff56b2008-01-26 14:10:37 +0100381 ccw_timeout_log [S390]
382 See Documentation/s390/CommonIO for details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
Paul Menage8bab8dd2008-04-04 14:29:57 -0700384 cgroup_disable= [KNL] Disable a particular controller
385 Format: {name of the controller(s) to disable}
386 {Currently supported controllers - "memory"}
387
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 checkreqprot [SELINUX] Set initial checkreqprot flag value.
389 Format: { "0" | "1" }
390 See security/selinux/Kconfig help text.
Randy Dunlapa9913042005-10-23 12:57:11 -0700391 0 -- check protection applied by kernel (includes
392 any implied execute protection).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 1 -- check protection requested by application.
394 Default value is set via a kernel config option.
Randy Dunlapa9913042005-10-23 12:57:11 -0700395 Value can be changed at runtime via
396 /selinux/checkreqprot.
397
Sebastian Ott661ca0d2008-01-26 14:10:36 +0100398 cio_ignore= [S390]
399 See Documentation/s390/CommonIO for details.
400
401 cio_msg= [S390]
402 See Documentation/s390/CommonIO for details.
403
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700404 clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
john stultz734efb42006-06-26 00:25:05 -0700405 [Deprecated]
Matt LaPlante3f6dee92006-10-03 22:45:33 +0200406 Forces specified clocksource (if available) to be used
john stultz734efb42006-06-26 00:25:05 -0700407 when calculating gettimeofday(). If specified
Matt LaPlante3f6dee92006-10-03 22:45:33 +0200408 clocksource is not available, it defaults to PIT.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 Format: { pit | tsc | cyclone | pmtmr }
410
Randy Dunlap3d6ac982007-05-23 13:58:16 -0700411 clocksource= [GENERIC_TIME] Override the default clocksource
412 Format: <string>
413 Override the default clocksource and use the clocksource
414 with the name specified.
415 Some clocksource names to choose from, depending on
416 the platform:
417 [all] jiffies (this is the base, fallback clocksource)
418 [ACPI] acpi_pm
419 [ARM] imx_timer1,OSTS,netx_timer,mpu_timer2,
420 pxa_timer,timer3,32k_counter,timer0_1
421 [AVR32] avr32
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700422 [X86-32] pit,hpet,tsc,vmi-timer;
Randy Dunlap3d6ac982007-05-23 13:58:16 -0700423 scx200_hrt on Geode; cyclone on IBM x440
424 [MIPS] MIPS
425 [PARISC] cr16
426 [S390] tod
427 [SH] SuperH
428 [SPARC64] tick
429 [X86-64] hpet,tsc
430
Andi Kleenac72e782008-01-30 13:33:21 +0100431 clearcpuid=BITNUM [X86]
432 Disable CPUID feature X for the kernel. See
433 include/asm-x86/cpufeature.h for the valid bit numbers.
434 Note the Linux specific bits are not necessarily
435 stable over kernel options, but the vendor specific
436 ones should be.
437 Also note that user programs calling CPUID directly
438 or using the feature without checking anything
439 will still see it. This just prevents it from
440 being used by the kernel or shown in /proc/cpuinfo.
441 Also note the kernel might malfunction if you disable
442 some critical bits.
443
Arjan van de Vena25bd942008-01-30 13:33:08 +0100444 code_bytes [IA32/X86_64] How many bytes of object code to print
445 in an oops report.
Chuck Ebbert86c41832007-02-13 13:26:25 +0100446 Range: 0 - 8192
447 Default: 64
448
Andi Kleenf9262c12006-03-08 17:57:25 -0800449 disable_8254_timer
450 enable_8254_timer
451 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
452 over the 8254 in addition to over the IO-APIC. The
453 kernel tries to set a sensible default.
454
Thomas Gleixnerb17530b2007-10-19 20:35:02 +0200455 hpet= [X86-32,HPET] option to control HPET usage
456 Format: { enable (default) | disable | force }
457 disable: disable HPET and use PIT instead
Carlos Corbachod79a5f82007-10-19 18:51:27 +0100458 force: allow force enabled of undocumented chips (ICH4,
459 VIA, nVidia)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 com20020= [HW,NET] ARCnet - COM20020 chipset
Randy Dunlapa9913042005-10-23 12:57:11 -0700462 Format:
463 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464
465 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
466 Format: <io>[,<irq>]
467
Randy Dunlapa9913042005-10-23 12:57:11 -0700468 com90xx= [HW,NET]
469 ARCnet - COM90xx chipset (memory-mapped buffers)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 Format: <io>[,<irq>[,<memstart>]]
471
472 condev= [HW,S390] console device
473 conmode=
Randy Dunlapa9913042005-10-23 12:57:11 -0700474
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 console= [KNL] Output console device and options.
476
477 tty<n> Use the virtual console device <n>.
478
479 ttyS<n>[,options]
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800480 ttyUSB0[,options]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 Use the specified serial port. The options are of
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800482 the form "bbbbpnf", where "bbbb" is the baud rate,
483 "p" is parity ("n", "o", or "e"), "n" is number of
484 bits, and "f" is flow control ("r" for RTS or
485 omit it). Default is "9600n8".
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800487 See Documentation/serial-console.txt for more
488 information. See
489 Documentation/networking/netconsole.txt for an
490 alternative.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700492 uart[8250],io,<addr>[,options]
493 uart[8250],mmio,<addr>[,options]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 Start an early, polled-mode console on the 8250/16550
495 UART at the specified I/O port or MMIO address,
496 switching to the matching ttyS device later. The
497 options are the same as for ttyS, above.
498
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700499 earlycon= [KNL] Output early console device and options.
500 uart[8250],io,<addr>[,options]
501 uart[8250],mmio,<addr>[,options]
502 Start an early, polled-mode console on the 8250/16550
503 UART at the specified I/O port or MMIO address.
504 The options are the same as for ttyS, above.
505
Andres Salomon8f4ce8c2007-10-18 03:04:50 -0700506 no_console_suspend
507 [HW] Never suspend the console
508 Disable suspending of consoles during suspend and
509 hibernate operations. Once disabled, debugging
510 messages can reach various consoles while the rest
511 of the system is being put to sleep (ie, while
512 debugging driver suspend/resume hooks). This may
513 not work reliably with all consoles, but is known
514 to work with serial and VGA consoles.
515
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Randy Dunlapa9913042005-10-23 12:57:11 -0700517 Format:
518 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519
Eric W. Biedermandc009d92005-06-25 14:57:52 -0700520 crashkernel=nn[KMG]@ss[KMG]
521 [KNL] Reserve a chunk of physical memory to
522 hold a kernel to switch to with kexec on panic.
523
Bernhard Wallefb391592007-10-18 23:41:02 -0700524 crashkernel=range1:size1[,range2:size2,...][@offset]
525 [KNL] Same as above, but depends on the memory
526 in the running system. The syntax of range is
527 start-[end] where start and end are both
528 a memory unit (amount[KMG]). See also
529 Documentation/kdump/kdump.txt for a example.
530
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 cs4232= [HW,OSS]
532 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
533
534 cs89x0_dma= [HW,NET]
535 Format: <dma>
536
537 cs89x0_media= [HW,NET]
538 Format: { rj45 | aui | bnc }
Randy Dunlapa9913042005-10-23 12:57:11 -0700539
Randy Dunlapa9913042005-10-23 12:57:11 -0700540 dasd= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 See header of drivers/s390/block/dasd_devmap.c.
542
543 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
544 (one device per port)
545 Format: <port#>,<type>
546 See also Documentation/input/joystick-parport.txt
547
548 debug [KNL] Enable kernel debugging (events log level).
549
Ingo Molnarcae2ed92006-07-03 00:24:48 -0700550 debug_locks_verbose=
551 [KNL] verbose self-tests
552 Format=<0|1>
553 Print debugging info while doing the locking API
554 self-tests.
555 We default to 0 (no extra messages), setting it to
556 1 will print _a lot_ more information - normally
557 only useful to kernel developers.
558
Robert P. J. Day2d27a962008-02-03 15:18:45 +0200559 decnet.addr= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 Format: <area>[,<node>]
561 See also Documentation/networking/decnet.txt.
562
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000563 vt.default_blu= [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700564 Format: <blue0>,<blue1>,<blue2>,...,<blue15>
565 Change the default blue palette of the console.
566 This is a 16-member array composed of values
567 ranging from 0-255.
568
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000569 vt.default_grn= [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700570 Format: <green0>,<green1>,<green2>,...,<green15>
571 Change the default green palette of the console.
572 This is a 16-member array composed of values
573 ranging from 0-255.
574
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000575 vt.default_red= [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700576 Format: <red0>,<red1>,<red2>,...,<red15>
577 Change the default red palette of the console.
578 This is a 16-member array composed of values
579 ranging from 0-255.
580
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000581 vt.default_utf8=
582 [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700583 Format=<0|1>
584 Set system-wide default UTF-8 mode for all tty's.
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000585 Default is 1, i.e. UTF-8 mode is enabled for all
586 newly opened terminals.
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700587
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 dhash_entries= [KNL]
589 Set number of hash buckets for dentry cache.
Randy Dunlapa9913042005-10-23 12:57:11 -0700590
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 digi= [HW,SERIAL]
592 IO parameters + enable/disable command.
593
594 digiepca= [HW,SERIAL]
595 See drivers/char/README.epca and
596 Documentation/digiepca.txt.
597
Yinghai Lu093af8d2008-01-30 13:33:32 +0100598 disable_mtrr_trim [X86, Intel and AMD only]
Jesse Barnes99fc8d42008-01-30 13:33:18 +0100599 By default the kernel will trim any uncacheable
600 memory out of your available memory pool based on
601 MTRR settings. This parameter disables that behavior,
602 possibly causing your machine to run very slowly.
603
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 dmasound= [HW,OSS] Sound subsystem buffers
605
606 dscc4.setup= [NET]
607
608 dtc3181e= [HW,SCSI]
609
Robin Getz0ae53642007-10-09 17:24:49 +0800610 earlyprintk= [X86-32,X86-64,SH,BLACKFIN]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 earlyprintk=vga
612 earlyprintk=serial[,ttySn[,baudrate]]
613
Randy Dunlapa9913042005-10-23 12:57:11 -0700614 Append ",keep" to not disable it when the real console
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 takes over.
616
617 Only vga or serial at a time, not both.
618
619 Currently only ttyS0 and ttyS1 are supported.
620
621 Interaction with the standard serial driver is not
622 very good.
623
624 The VGA output is eventually overwritten by the real
625 console.
626
627 eata= [HW,SCSI]
628
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 edd= [EDD]
630 Format: {"of[f]" | "sk[ipmbr]"}
631 See comment in arch/i386/boot/edd.S
632
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 eisa_irq_edge= [PARISC,HW]
634 See header of drivers/parisc/eisa.c.
635
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700636 elanfreq= [X86-32]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 See comment before function elanfreq_setup() in
638 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
639
640 elevator= [IOSCHED]
Randy Dunlap16ab3ad2006-01-14 13:21:20 -0800641 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
Randy Dunlapa9913042005-10-23 12:57:11 -0700642 See Documentation/block/as-iosched.txt and
643 Documentation/block/deadline-iosched.txt for details.
644
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700645 elfcorehdr= [X86-32, X86_64]
Randy Dunlapa9913042005-10-23 12:57:11 -0700646 Specifies physical address of start of kernel core
Vivek Goyalaac04b32006-01-09 20:51:47 -0800647 image elf header. Generally kexec loader will
648 pass this option to capture kernel.
649 See Documentation/kdump/kdump.txt for details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
651 enforcing [SELINUX] Set initial enforcing status.
652 Format: {"0" | "1"}
653 See security/selinux/Kconfig help text.
654 0 -- permissive (log only, no denials).
655 1 -- enforcing (deny and log).
656 Default value is 0.
657 Value can be changed at runtime via /selinux/enforce.
658
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 es1371= [HW,OSS]
660 Format: <spdif>,[<nomix>,[<amplifier>]]
661 See also header of sound/oss/es1371.c.
Randy Dunlapa9913042005-10-23 12:57:11 -0700662
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 ether= [HW,NET] Ethernet cards parameters
664 This option is obsoleted by the "netdev=" option, which
665 has equivalent usage. See its documentation for details.
666
667 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
668 Format: <io>[,<irq>]
669
Akinobu Mitade1ba092006-12-08 02:39:42 -0800670 failslab=
671 fail_page_alloc=
672 fail_make_request=[KNL]
673 General fault injection mechanism.
674 Format: <interval>,<probability>,<space>,<times>
675 See also /Documentation/fault-injection/.
676
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 fd_mcs= [HW,SCSI]
678 See header of drivers/scsi/fd_mcs.c.
679
680 fdomain= [HW,SCSI]
681 See header of drivers/scsi/fdomain.c.
682
683 floppy= [HW]
684 See Documentation/floppy.txt.
685
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 gamecon.map[2|3]=
687 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
688 support via parallel port (up to 5 devices per port)
689 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
690 See also Documentation/input/joystick-parport.txt
691
692 gamma= [HW,DRM]
693
Yinghai Luaaf23042008-01-30 13:33:09 +0100694 gart_fix_e820= [X86_64] disable the fix e820 for K8 GART
695 Format: off | on
696 default: on
697
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 gdth= [HW,SCSI]
699 See header of drivers/scsi/gdth.c.
700
701 gpt [EFI] Forces disk with valid GPT signature but
702 invalid Protective MBR to be treated as GPT.
703
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 gvp11= [HW,SCSI]
705
706 hashdist= [KNL,NUMA] Large hashes allocated during boot
707 are distributed across NUMA nodes. Defaults on
708 for IA-64, off otherwise.
Randy Dunlapa9913042005-10-23 12:57:11 -0700709 Format: 0 | 1 (for off | on)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710
711 hcl= [IA-64] SGI's Hardware Graph compatibility layer
712
713 hd= [EIDE] (E)IDE hard drive subsystem geometry
714 Format: <cyl>,<head>,<sect>
715
716 hd?= [HW] (E)IDE subsystem
Randy Dunlap1c10e932008-03-07 21:53:50 +0100717 hd?lun= See Documentation/ide/ide.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718
719 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
720 size of <nn>. This works even on boxes that have no
721 highmem otherwise. This also works to reduce highmem
722 size on bigger boxes.
723
Thomas Gleixner54cdfdb2007-02-16 01:28:11 -0800724 highres= [KNL] Enable/disable high resolution timer mode.
725 Valid parameters: "on", "off"
726 Default: "on"
727
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 hisax= [HW,ISDN]
729 See Documentation/isdn/README.HiSax.
730
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700731 hugepages= [HW,X86-32,IA-64] Maximal number of HugeTLB pages.
Jon Tollefson4ec161c2008-01-04 09:59:50 +1100732 hugepagesz= [HW,IA-64,PPC] The size of the HugeTLB pages.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 i8042.direct [HW] Put keyboard port into non-translated mode
Matt LaPlante84eb8d02006-10-03 22:53:09 +0200735 i8042.dumbkbd [HW] Pretend that controller can only read data from
736 keyboard and cannot control its state
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 (Don't attempt to blink the leds)
738 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
Dmitry Torokhov945ef0d2005-09-04 01:42:00 -0500739 i8042.nokbd [HW] Don't check/create keyboard port
Jiri Kosina75d08c72008-03-13 16:13:59 -0400740 i8042.noloop [HW] Disable the AUX Loopback command while probing
741 for the AUX port
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 i8042.nomux [HW] Don't check presence of an active multiplexing
743 controller
744 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
745 controllers
746 i8042.panicblink=
747 [HW] Frequency with which keyboard LEDs should blink
748 when kernel panics (default is 0.5 sec)
749 i8042.reset [HW] Reset the controller during init and cleanup
750 i8042.unlock [HW] Unlock (ignore) the keylock
751
752 i810= [HW,DRM]
753
Dmitry Torokhove70c9d52005-06-25 14:54:25 -0700754 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
755 indicates that the driver is running on unsupported
756 hardware.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
758 does not match list of supported models.
759 i8k.power_status
760 [HW] Report power status in /proc/i8k
761 (disabled by default)
762 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
763 capability is set.
764
765 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
766 See Documentation/mca.txt.
767
768 icn= [HW,ISDN]
769 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
770
771 ide= [HW] (E)IDE subsystem
Greg Kroah-Hartmana594eeb2008-04-18 00:46:20 +0200772 Format: ide=nodma or ide=doubler
Randy Dunlap1c10e932008-03-07 21:53:50 +0100773 See Documentation/ide/ide.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
Randy Dunlap1c10e932008-03-07 21:53:50 +0100776 See Documentation/ide/ide.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777
Andi Kleenf039b752007-05-02 19:27:12 +0200778 idle= [X86]
779 Format: idle=poll or idle=mwait
780 Poll forces a polling idle loop that can slightly improves the performance
781 of waking up a idle CPU, but will use a lot of power and make the system
782 run hot. Not recommended.
783 idle=mwait. On systems which support MONITOR/MWAIT but the kernel chose
784 to not use it because it doesn't save as much power as a normal idle
785 loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
786 as idle=poll.
Randy Dunlapa9913042005-10-23 12:57:11 -0700787
Denis Cheng594765a2008-02-06 02:57:49 +0100788 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
789 Claim all unknown PCI IDE storage controllers.
790
Ingo Molnar792908222006-12-06 20:40:51 -0800791 ignore_loglevel [KNL]
792 Ignore loglevel setting - this will print /all/
793 kernel messages to the console. Useful for debugging.
794
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 ihash_entries= [KNL]
796 Set number of hash buckets for inode cache.
797
798 in2000= [HW,SCSI]
799 See header of drivers/scsi/in2000.c.
800
801 init= [KNL]
802 Format: <full_path>
803 Run specified binary instead of /sbin/init as init
804 process.
805
806 initcall_debug [KNL] Trace initcalls as they are executed. Useful
807 for working out where the kernel is dying during
808 startup.
809
810 initrd= [BOOT] Specify the location of the initial ramdisk
811
812 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
813 Format: <irq>
814
815 inttest= [IA64]
816
Pavel Machekb552da82008-03-19 15:58:11 +0100817 iommu= [x86]
818 off
819 force
820 noforce
821 biomerge
822 panic
823 nopanic
824 merge
825 nomerge
826 forcesac
827 soft
828
829
Keshavamurthy, Anil Sba395922007-10-21 16:41:49 -0700830 intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option
831 off
832 Disable intel iommu driver.
833 igfx_off [Default Off]
834 By default, gfx is mapped as normal device. If a gfx
835 device has a dedicated DMAR unit, the DMAR unit is
836 bypassed by not enabling DMAR with this option. In
837 this case, gfx device will use physical address for
838 DMA.
Keshavamurthy, Anil S7d3b03c2007-10-21 16:41:53 -0700839 forcedac [x86_64]
840 With this option iommu will not optimize to look
841 for io virtual address below 32 bit forcing dual
842 address cycle on pci bus for cards supporting greater
843 than 32 bit addressing. The default is to look
844 for translation below 32 bit and if not available
845 then look in the higher range.
mark gross5e0d2a62008-03-04 15:22:08 -0800846 strict [Default Off]
847 With this option on every unmap_single operation will
848 result in a hardware IOTLB flush operation as opposed
849 to batching them for performance.
Keshavamurthy, Anil Sba395922007-10-21 16:41:49 -0700850
Rene Hermanb02aae92008-01-30 13:30:05 +0100851 io_delay= [X86-32,X86-64] I/O delay method
Ingo Molnar6e7c4022008-01-30 13:30:05 +0100852 0x80
853 Standard port 0x80 based delay
854 0xed
855 Alternate port 0xed based delay (needed on some systems)
Rene Hermanb02aae92008-01-30 13:30:05 +0100856 udelay
Ingo Molnar6e7c4022008-01-30 13:30:05 +0100857 Simple two microseconds delay
858 none
859 No delay
Rene Hermanb02aae92008-01-30 13:30:05 +0100860
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 io7= [HW] IO7 for Marvel based alpha systems
862 See comment before marvel_specify_io7 in
863 arch/alpha/kernel/core_marvel.c.
864
865 ip= [IP_PNP]
J. Bruce Fields6ded55d2008-04-07 15:59:03 -0400866 See Documentation/filesystems/nfsroot.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
868 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
Randy Dunlapc8facbb2007-07-31 00:37:40 -0700869 See comment before ip2_setup() in
870 drivers/char/ip2/ip2base.c.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871
872 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
873 See header of drivers/scsi/ips.c.
874
Simon Horman72c4a132006-09-13 19:57:18 -0700875 ports= [IP_VS_FTP] IPVS ftp helper module
876 Default is 21.
877 Up to 8 (IP_VS_APP_MAX_PORTS) ports
878 may be specified.
879 Format: <port>,<port>....
880
Alan Cox200803d2005-06-28 20:45:18 -0700881 irqfixup [HW]
882 When an interrupt is not handled search all handlers
883 for it. Intended to get systems with badly broken
884 firmware running.
885
886 irqpoll [HW]
887 When an interrupt is not handled search all handlers
888 for it. Also check all handlers each timer
889 interrupt. Intended to get systems with badly broken
890 firmware running.
891
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 isapnp= [ISAPNP]
Randy Dunlapa9913042005-10-23 12:57:11 -0700893 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894
895 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
Derek Fults22f2e282006-12-06 20:37:11 -0800896 Format:
897 <cpu number>,...,<cpu number>
898 or
899 <cpu number>-<cpu number> (must be a positive range in ascending order)
900 or a mixture
901 <cpu number>,...,<cpu number>-<cpu number>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902 This option can be used to specify one or more CPUs
903 to isolate from the general SMP balancing and scheduling
904 algorithms. The only way to move a process onto or off
905 an "isolated" CPU is via the CPU affinity syscalls.
906 <cpu number> begins at 0 and the maximum value is
907 "number of CPUs in system - 1".
908
909 This option is the preferred way to isolate CPUs. The
Randy Dunlapa9913042005-10-23 12:57:11 -0700910 alternative -- manually setting the CPU mask of all
911 tasks in the system -- can cause problems and
912 suboptimal load balancer performance.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913
Randy Dunlapa9913042005-10-23 12:57:11 -0700914 iucv= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915
916 js= [HW,JOY] Analog joystick
917 See Documentation/input/joystick.txt.
918
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700919 kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
Mel Gormaned7ed362007-07-17 04:03:14 -0700920 specifies the amount of memory usable by the kernel
921 for non-movable allocations. The requested amount is
922 spread evenly throughout all nodes in the system. The
923 remaining memory in each node is used for Movable
924 pages. In the event, a node is too small to have both
925 kernelcore and Movable pages, kernelcore pages will
926 take priority and other nodes will have a larger number
927 of kernelcore pages. The Movable zone is used for the
928 allocation of pages that may be reclaimed or moved
929 by the page migration subsystem. This means that
930 HugeTLB pages may not be allocated from this zone.
931 Note that allocations like PTEs-from-HighMem still
932 use the HighMem zone if it exists, and the Normal
933 zone if it does not.
934
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700935 movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
Mel Gorman7e63efe2007-07-17 04:03:15 -0700936 is similar to kernelcore except it specifies the
937 amount of memory used for migratable allocations.
938 If both kernelcore and movablecore is specified,
939 then kernelcore will be at *least* the specified
940 value but may be more. If movablecore on its own
941 is specified, the administrator must be careful
942 that the amount of memory usable for all allocations
943 is not too small.
944
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 keepinitrd [HW,ARM]
946
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700947 kstack=N [X86-32,X86-64] Print N words from the kernel stack
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948 in oops dumps.
949
Jason Wessel6cdf6e02008-04-17 20:05:38 +0200950 kgdboc= [HW] kgdb over consoles.
951 Requires a tty driver that supports console polling.
952 (only serial suported for now)
953 Format: <serial_device>[,baud]
954
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 l2cr= [PPC]
956
Robert Brosea78bfbf2008-03-29 07:20:23 +1100957 l3cr= [PPC]
958
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700959 lapic [X86-32,APIC] Enable the local APIC even if BIOS
Randy Dunlapa9913042005-10-23 12:57:11 -0700960 disabled it.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700962 lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer in
Thomas Gleixnere585bef2007-03-23 16:08:01 +0100963 C2 power state.
964
FD Camifcb71f62008-01-06 19:08:56 +0100965 libata.dma= [LIBATA] DMA control
966 libata.dma=0 Disable all PATA and SATA DMA
967 libata.dma=1 PATA and SATA Disk DMA only
968 libata.dma=2 ATAPI (CDROM) DMA only
969 libata.dma=4 Compact Flash DMA only
970 Combinations also work, so libata.dma=3 enables DMA
971 for disks and CDROMs, but not CFs.
972
Dave Jones78e70c22007-09-27 11:50:13 -0400973 libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume
974 when set.
975 Format: <int>
976
Tejun Heo33267322008-02-13 09:15:09 +0900977 libata.force= [LIBATA] Force configurations. The format is comma
978 separated list of "[ID:]VAL" where ID is
979 PORT[:DEVICE]. PORT and DEVICE are decimal numbers
980 matching port, link or device. Basically, it matches
981 the ATA ID string printed on console by libata. If
982 the whole ID part is omitted, the last PORT and DEVICE
983 values are used. If ID hasn't been specified yet, the
984 configuration applies to all ports, links and devices.
985
986 If only DEVICE is omitted, the parameter applies to
987 the port and all links and devices behind it. DEVICE
988 number of 0 either selects the first device or the
989 first fan-out link behind PMP device. It does not
990 select the host link. DEVICE number of 15 selects the
991 host link and device attached to it.
992
993 The VAL specifies the configuration to force. As long
994 as there's no ambiguity shortcut notation is allowed.
995 For example, both 1.5 and 1.5G would work for 1.5Gbps.
996 The following configurations can be forced.
997
998 * Cable type: 40c, 80c, short40c, unk, ign or sata.
999 Any ID with matching PORT is used.
1000
1001 * SATA link speed limit: 1.5Gbps or 3.0Gbps.
1002
1003 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
1004 udma[/][16,25,33,44,66,100,133] notation is also
1005 allowed.
1006
1007 * [no]ncq: Turn on or off NCQ.
1008
1009 If there are multiple matching configurations changing
1010 the same attribute, the last one is used.
1011
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012 load_ramdisk= [RAM] List of ramdisks to load from floppy
1013 See Documentation/ramdisk.txt.
1014
Randy Dunlapa6b25b62006-01-14 13:21:19 -08001015 lockd.nlm_grace_period=P [NFS] Assign grace period.
1016 Format: <integer>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017
Randy Dunlapa6b25b62006-01-14 13:21:19 -08001018 lockd.nlm_tcpport=N [NFS] Assign TCP port.
1019 Format: <integer>
1020
1021 lockd.nlm_timeout=T [NFS] Assign timeout value.
1022 Format: <integer>
1023
1024 lockd.nlm_udpport=M [NFS] Assign UDP port.
1025 Format: <integer>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001026
1027 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
1028 Format: <irq>
1029
1030 loglevel= All Kernel Messages with a loglevel smaller than the
1031 console loglevel will be printed to the console. It can
1032 also be changed with klogd or other programs. The
1033 loglevels are defined as follows:
1034
1035 0 (KERN_EMERG) system is unusable
1036 1 (KERN_ALERT) action must be taken immediately
1037 2 (KERN_CRIT) critical conditions
1038 3 (KERN_ERR) error conditions
1039 4 (KERN_WARNING) warning conditions
1040 5 (KERN_NOTICE) normal but significant condition
1041 6 (KERN_INFO) informational
1042 7 (KERN_DEBUG) debug-level messages
1043
1044 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
Randy Dunlapa9913042005-10-23 12:57:11 -07001045 Format: { n | nk | nM }
1046 n must be a power of two. The default size
1047 is set in the kernel config file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001048
Randy Dunlapaccaa242007-10-16 01:29:37 -07001049 logo.nologo [FB] Disables display of the built-in Linux logo.
1050 This may be used to provide more screen space for
1051 kernel log messages and is useful when debugging
1052 kernel boot problems.
1053
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054 lp=0 [LP] Specify parallel ports to use, e.g,
1055 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
1056 lp=reset first parallel port). 'lp=0' disables the
1057 lp=auto printer driver. 'lp=reset' (which can be
1058 specified in addition to the ports) causes
1059 attached printers to be reset. Using
1060 lp=port1,port2,... specifies the parallel ports
1061 to associate lp devices with, starting with
1062 lp0. A port specification may be 'none' to skip
1063 that lp device, or a parport name such as
1064 'parport0'. Specifying 'lp=auto' instead of a
1065 port specification list means that device IDs
1066 from each port should be examined, to see if
1067 an IEEE 1284-compliant printer is attached; if
1068 so, the driver will manage that printer.
1069 See also header of drivers/char/lp.c.
1070
1071 lpj=n [KNL]
1072 Sets loops_per_jiffy to given constant, thus avoiding
1073 time-consuming boot-time autodetection (up to 250 ms per
1074 CPU). 0 enables autodetection (default). To determine
1075 the correct value for your kernel, boot with normal
1076 autodetection and see what value is printed. Note that
1077 on SMP systems the preset will be applied to all CPUs,
1078 which is likely to cause problems if your CPUs need
1079 significantly divergent settings. An incorrect value
1080 will cause delays in the kernel to be wrong, leading to
1081 unpredictable I/O errors and other breakage. Although
1082 unlikely, in the extreme case this might damage your
1083 hardware.
1084
1085 ltpc= [NET]
1086 Format: <io>,<irq>,<dma>
1087
Randy Dunlapa9913042005-10-23 12:57:11 -07001088 mac5380= [HW,SCSI] Format:
1089 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090
Randy Dunlapa9913042005-10-23 12:57:11 -07001091 mac53c9x= [HW,SCSI] Format:
1092 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093
Randy Dunlapa9913042005-10-23 12:57:11 -07001094 machvec= [IA64] Force the use of a particular machine-vector
1095 (machvec) in a generic kernel.
1096 Example: machvec=hpzx1_swiotlb
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097
Randy Dunlapa9913042005-10-23 12:57:11 -07001098 max_loop= [LOOP] Maximum number of loopback devices that can
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099 be mounted
1100 Format: <1-256>
1101
1102 maxcpus= [SMP] Maximum number of processors that an SMP kernel
Len Brown61ec7562007-08-16 03:34:22 -04001103 should make use of. maxcpus=n : n >= 0 limits the
1104 kernel to using 'n' processors. n=0 is a special case,
1105 it is equivalent to "nosmp", which also disables
1106 the IO APIC.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107
Bob Picco2b2c3752005-06-29 18:00:00 -07001108 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
1109 equal to this physical address is ignored.
1110
Randy Dunlapa9913042005-10-23 12:57:11 -07001111 max_luns= [SCSI] Maximum number of LUNs to probe.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112 Should be between 1 and 2^32-1.
1113
1114 max_report_luns=
Randy Dunlapa9913042005-10-23 12:57:11 -07001115 [SCSI] Maximum number of LUNs received.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 Should be between 1 and 16384.
1117
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118 mcatest= [IA-64]
1119
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001120 mce [X86-32] Machine Check Exception
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121
Andi Kleen909dd322007-10-17 18:04:38 +02001122 mce=option [X86-64] See Documentation/x86_64/boot-options.txt
1123
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 md= [HW] RAID subsystems devices and level
1125 See Documentation/md.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -07001126
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127 mdacon= [MDA]
1128 Format: <first>,<last>
1129 Specifies range of consoles to be captured by the MDA.
Randy Dunlapa9913042005-10-23 12:57:11 -07001130
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
1132 Amount of memory to be used when the kernel is not able
1133 to see the whole system memory or for test.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001134 [X86-32] Use together with memmap= to avoid physical
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 address space collisions. Without memmap= PCI devices
1136 could be placed at addresses belonging to unused RAM.
1137
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001138 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139 memory.
1140
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001141 memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142 E820 memory map, as specified by the user.
1143 Such memmap=exactmap lines can be constructed based on
1144 BIOS output or other requirements. See the memmap=nn@ss
1145 option description.
1146
1147 memmap=nn[KMG]@ss[KMG]
1148 [KNL] Force usage of a specific region of memory
1149 Region of memory to be used, from ss to ss+nn.
1150
1151 memmap=nn[KMG]#ss[KMG]
1152 [KNL,ACPI] Mark specific memory as ACPI data.
1153 Region of memory to be used, from ss to ss+nn.
1154
1155 memmap=nn[KMG]$ss[KMG]
1156 [KNL,ACPI] Mark specific memory as reserved.
1157 Region of memory to be used, from ss to ss+nn.
Pavel Machek13128482008-03-24 12:29:43 -07001158 Example: Exclude memory from 0x18690000-0x1869ffff
1159 memmap=64K$0x18690000
1160 or
1161 memmap=0x10000$0x18690000
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162
Yinghai Luc64df702008-03-21 18:56:19 -07001163 memtest= [KNL,X86_64] Enable memtest
1164 Format: <integer>
1165 range: 0,4 : pattern number
1166 default : 0 <disable>
1167
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168 meye.*= [HW] Set MotionEye Camera parameters
1169 See Documentation/video4linux/meye.txt.
1170
Andres Salomon8f368812007-10-12 23:04:06 +02001171 mfgpt_irq= [IA-32] Specify the IRQ to use for the
1172 Multi-Function General Purpose Timers on AMD Geode
1173 platforms.
1174
Willy Tarreaue6c4dc62008-01-30 13:33:33 +01001175 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
1176 the BIOS has incorrectly applied a workaround. TinyBIOS
1177 version 0.98 is known to be affected, 0.99 fixes the
1178 problem by letting the user disable the workaround.
1179
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 mga= [HW,DRM]
1181
1182 mousedev.tap_time=
1183 [MOUSE] Maximum time between finger touching and
1184 leaving touchpad surface for touch to be considered
1185 a tap and be reported as a left button click (for
1186 touchpads working in absolute mode only).
1187 Format: <msecs>
1188 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
1189 reporting absolute coordinates, such as tablets
1190 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
1191 reporting absolute coordinates, such as tablets
1192
1193 mpu401= [HW,OSS]
1194 Format: <io>,<irq>
1195
1196 MTD_Partition= [MTD]
1197 Format: <name>,<region-number>,<size>,<offset>
1198
Randy Dunlapa9913042005-10-23 12:57:11 -07001199 MTD_Region= [MTD] Format:
1200 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001201
1202 mtdparts= [MTD]
Randy Dunlapc8facbb2007-07-31 00:37:40 -07001203 See drivers/mtd/cmdlinepart.c.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204
1205 mtouchusb.raw_coordinates=
Randy Dunlapa9913042005-10-23 12:57:11 -07001206 [HW] Make the MicroTouch USB driver use raw coordinates
1207 ('y', default) or cooked coordinates ('n')
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208
1209 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
1210
1211 NCR_D700= [HW,SCSI]
1212 See header of drivers/scsi/NCR_D700.c.
1213
1214 ncr5380= [HW,SCSI]
1215
1216 ncr53c400= [HW,SCSI]
1217
1218 ncr53c400a= [HW,SCSI]
1219
1220 ncr53c406a= [HW,SCSI]
1221
1222 ncr53c8xx= [HW,SCSI]
1223
1224 netdev= [NET] Network devices parameters
1225 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
1226 Note that mem_start is often overloaded to mean
1227 something different and driver-specific.
Randy Dunlapa9913042005-10-23 12:57:11 -07001228 This usage is only documented in each driver source
1229 file if at all.
1230
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231 nfsaddrs= [NFS]
J. Bruce Fields6ded55d2008-04-07 15:59:03 -04001232 See Documentation/filesystems/nfsroot.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233
1234 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
J. Bruce Fields6ded55d2008-04-07 15:59:03 -04001235 See Documentation/filesystems/nfsroot.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236
Trond Myklebusta72b4422006-01-03 09:55:41 +01001237 nfs.callback_tcpport=
1238 [NFS] set the TCP port on which the NFSv4 callback
1239 channel should listen.
1240
Trond Myklebust58df0952006-01-03 09:55:57 +01001241 nfs.idmap_cache_timeout=
1242 [NFS] set the maximum lifetime for idmapper cache
1243 entries.
1244
Trond Myklebustf43bf0b2007-10-09 12:01:04 -04001245 nfs.enable_ino64=
1246 [NFS] enable 64-bit inode numbers.
1247 If zero, the NFS client will fake up a 32-bit inode
1248 number for the readdir() and stat() syscalls instead
1249 of returning the full 64-bit number.
1250 The default is to return 64-bit inode numbers.
1251
Haavard Skinnemoene7ba1762007-10-10 14:58:29 +02001252 nmi_debug= [KNL,AVR32] Specify one or more actions to take
1253 when a NMI is triggered.
1254 Format: [state][,regs][,debounce][,die]
1255
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001256 nmi_watchdog= [KNL,BUGS=X86-32] Debugging features for SMP kernels
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001258 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 emulation library even if a 387 maths coprocessor
1260 is present.
1261
Christoph Lameterc1aee212007-05-31 00:40:47 -07001262 noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
1263 caches in the slab allocator. Saves per-node memory,
1264 but will impact performance.
Paul Menage3395ee02006-12-06 20:32:16 -08001265
Randy Dunlapa9913042005-10-23 12:57:11 -07001266 noalign [KNL,ARM]
1267
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268 noapic [SMP,APIC] Tells the kernel to not make use of any
1269 IOAPICs that may be present in the system.
1270
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271 nobats [PPC] Do not use BATs for mapping kernel lowmem
1272 on "Classic" PPC cores.
1273
1274 nocache [ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001275
Shailabh Nagar163ecdf2006-07-30 03:03:11 -07001276 nodelayacct [KNL] Disable per-task delay accounting
1277
Linus Torvalds1da177e2005-04-16 15:20:36 -07001278 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1279
Huang, Ying8b2cb7a2008-01-30 13:32:11 +01001280 noefi [X86-32,X86-64] Disable EFI runtime services support.
1281
Linus Torvalds1da177e2005-04-16 15:20:36 -07001282 noexec [IA-64]
1283
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001284 noexec [X86-32,X86-64]
Jiri Slabyf5a1b192008-04-12 10:28:25 +02001285 On X86-32 available only on PAE configured kernels.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 noexec=on: enable non-executable mappings (default)
Jiri Slabyf5a1b192008-04-12 10:28:25 +02001287 noexec=off: disable non-executable mappings
1288
1289 noexec32 [X86-64]
1290 This affects only 32-bit executables.
1291 noexec32=on: enable non-executable mappings (default)
1292 read doesn't imply executable mappings
1293 noexec32=off: disable non-executable mappings
1294 read implies executable mappings
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001296 nofxsr [BUGS=X86-32] Disables x86 floating point extended
Chuck Ebbert4f886512006-03-23 02:59:34 -08001297 register save and restore. The kernel will only save
1298 legacy floating-point registers on task switch.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299
Andi Kleen191679f2008-01-30 13:33:21 +01001300 noclflush [BUGS=X86] Don't use the CLFLUSH instruction
1301
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302 nohlt [BUGS=ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001303
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001304 no-hlt [BUGS=X86-32] Tells the kernel that the hlt
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305 instruction doesn't work correctly and not to
1306 use it.
1307
1308 nohalt [IA-64] Tells the kernel not to use the power saving
1309 function PAL_HALT_LIGHT when idle. This increases
1310 power-consumption. On the positive side, it reduces
1311 interrupt wake-up latency, which may improve performance
1312 in certain environments such as networked servers or
1313 real-time systems.
1314
Thomas Gleixner79bf2bb2007-02-16 01:28:03 -08001315 nohz= [KNL] Boottime enable/disable dynamic ticks
1316 Valid arguments: on, off
1317 Default: on
1318
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001319 noirqbalance [X86-32,SMP,KNL] Disable kernel irq balancing
Zachary Amsden8542b202006-12-07 02:14:09 +01001320
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001321 noirqdebug [X86-32] Disables the code which attempts to detect and
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 disable unhandled interrupt sources.
1323
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001324 no_timer_check [X86-32,X86_64,APIC] Disables the code which tests for
Zachary Amsden8542b202006-12-07 02:14:09 +01001325 broken timer IRQ sources.
1326
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327 noisapnp [ISAPNP] Disables ISA PnP code.
1328
1329 noinitrd [RAM] Tells the kernel not to load any configured
1330 initial RAM disk.
1331
1332 nointroute [IA-64]
1333
Tony Luck0aa366f2007-07-20 11:22:30 -07001334 nojitter [IA64] Disables jitter checking for ITC timers.
1335
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001336 nolapic [X86-32,APIC] Do not enable or use the local APIC.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001338 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
Thomas Gleixnerad62ca22007-03-22 00:11:21 -08001339
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 noltlbs [PPC] Do not use large page/tlb entries for kernel
1341 lowmem mapping on PPC40x.
1342
Horms312f1f02006-02-22 09:57:55 +09001343 nomca [IA-64] Disable machine check abort handling
1344
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001345 nomce [X86-32] Machine Check Exception
Hormsabe37e52006-04-01 01:36:09 +02001346
Andres Salomon83d73842007-10-12 23:04:06 +02001347 nomfgpt [X86-32] Disable Multi-Function General Purpose
1348 Timer usage (for AMD Geode machines).
1349
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001350 noreplace-paravirt [X86-32,PV_OPS] Don't patch paravirt_ops
Jeremy Fitzhardinge959b4fd2007-05-02 19:27:16 +02001351
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001352 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
Jeremy Fitzhardingeb7fb4af2007-05-02 19:27:13 +02001353 with UP alternatives
1354
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355 noresidual [PPC] Don't use residual data on PReP machines.
1356
Randy Dunlapa9913042005-10-23 12:57:11 -07001357 noresume [SWSUSP] Disables resume and restores original swap
1358 space.
1359
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 no-scroll [VGA] Disables scrollback.
1361 This is required for the Braillex ib80-piezo Braille
1362 reader made by F.H. Papenmeier (Germany).
1363
1364 nosbagart [IA-64]
1365
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001366 nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support.
Chuck Ebbert4f886512006-03-23 02:59:34 -08001367
Len Brown61ec7562007-08-16 03:34:22 -04001368 nosmp [SMP] Tells an SMP kernel to act as a UP kernel,
1369 and disable the IO APIC. legacy for "maxcpus=0".
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370
Dave Jones97842212007-07-15 23:41:05 -07001371 nosoftlockup [KNL] Disable the soft-lockup detector.
1372
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373 nosync [HW,M68K] Disables sync negotiation for all devices.
1374
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001375 notsc [BUGS=X86-32] Disable Time Stamp Counter
Linus Torvalds1da177e2005-04-16 15:20:36 -07001376
1377 nousb [USB] Disable the USB subsystem
1378
1379 nowb [ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001380
Fenghua Yua6c75b862008-03-14 13:57:08 -07001381 nptcg= [IA64] Override max number of concurrent global TLB
1382 purges which is reported from either PAL_VM_SUMMARY or
1383 SAL PALO.
1384
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07001385 numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
1386 one of ['zone', 'node', 'default'] can be specified
1387 This can be set from sysctl after boot.
1388 See Documentation/sysctl/vm.txt for details.
1389
Dave Jonesa61c2d72006-01-07 23:18:19 +00001390 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1391
Linus Torvalds1da177e2005-04-16 15:20:36 -07001392 opl3= [HW,OSS]
1393 Format: <io>
1394
Linus Torvalds1da177e2005-04-16 15:20:36 -07001395 oprofile.timer= [HW]
1396 Use timer interrupt instead of performance counters
1397
Linus Torvalds1da177e2005-04-16 15:20:36 -07001398 osst= [HW,SCSI] SCSI Tape Driver
1399 Format: <buffer_size>,<write_threshold>
1400 See also Documentation/scsi/st.txt.
1401
1402 panic= [KNL] Kernel behaviour on panic
1403 Format: <timeout>
1404
1405 parkbd.port= [HW] Parallel port number the keyboard adapter is
1406 connected to, default is 0.
1407 Format: <parport#>
1408 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1409 0 for XT, 1 for AT (default is AT).
Randy Dunlapa9913042005-10-23 12:57:11 -07001410 Format: <mode>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411
Randy Dunlapa9913042005-10-23 12:57:11 -07001412 parport= [HW,PPT] Specify parallel ports. 0 disables.
1413 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1414 Use 'auto' to force the driver to use any
1415 IRQ/DMA settings detected (the default is to
1416 ignore detected IRQ/DMA settings because of
1417 possible conflicts). You can specify the base
1418 address, IRQ, and DMA settings; IRQ and DMA
1419 should be numbers, or 'auto' (for using detected
1420 settings on that particular port), or 'nofifo'
1421 (to avoid using a FIFO even if it is detected).
1422 Parallel ports are assigned in the order they
1423 are specified on the command line, starting
1424 with parport0.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425
Randy Dunlapa9913042005-10-23 12:57:11 -07001426 parport_init_mode= [HW,PPT]
1427 Configure VIA parallel port to operate in
1428 a specific mode. This is necessary on Pegasos
1429 computer where firmware has no options for setting
1430 up parallel port mode and sets it to spp.
1431 Currently this function knows 686a and 8231 chips.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432 Format: [spp|ps2|epp|ecp|ecpepp]
1433
Randy Dunlapa9913042005-10-23 12:57:11 -07001434 pas2= [HW,OSS] Format:
1435 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1436
Linus Torvalds1da177e2005-04-16 15:20:36 -07001437 pas16= [HW,SCSI]
1438 See header of drivers/scsi/pas16.c.
1439
Andrew Mortondd287792006-03-23 03:00:57 -08001440 pause_on_oops=
1441 Halt all CPUs after the first oops has been printed for
1442 the specified number of seconds. This is to be used if
1443 your oopses keep scrolling off the screen.
1444
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445 pcbit= [HW,ISDN]
1446
1447 pcd. [PARIDE]
1448 See header of drivers/block/paride/pcd.c.
1449 See also Documentation/paride.txt.
1450
Randy Dunlapa9913042005-10-23 12:57:11 -07001451 pci=option[,option...] [PCI] various PCI subsystem options:
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001452 off [X86-32] don't probe for the PCI bus
1453 bios [X86-32] force use of PCI BIOS, don't access
Randy Dunlapa9913042005-10-23 12:57:11 -07001454 the hardware directly. Use this if your machine
1455 has a non-standard PCI host bridge.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001456 nobios [X86-32] disallow use of PCI BIOS, only direct
Randy Dunlapa9913042005-10-23 12:57:11 -07001457 hardware access methods are allowed. Use this
1458 if you experience crashes upon bootup and you
1459 suspect they are caused by the BIOS.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001460 conf1 [X86-32] Force use of PCI Configuration
Randy Dunlapa9913042005-10-23 12:57:11 -07001461 Mechanism 1.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001462 conf2 [X86-32] Force use of PCI Configuration
Randy Dunlapa9913042005-10-23 12:57:11 -07001463 Mechanism 2.
Randy Dunlap7f785762007-10-05 13:17:58 -07001464 noaer [PCIE] If the PCIEAER kernel config parameter is
1465 enabled, this kernel boot option can be used to
1466 disable the use of PCIE advanced error reporting.
Jeff Garzik32a2eea2007-10-11 16:57:27 -04001467 nodomains [PCI] Disable support for multiple PCI
1468 root domains (aka PCI segments, in ACPI-speak).
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001469 nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI
Bjorn Helgaas61be6d62006-02-15 15:17:43 -08001470 Configuration
Matthew Wilcox309e57d2006-03-05 22:33:34 -07001471 nomsi [MSI] If the PCI_MSI kernel config parameter is
1472 enabled, this kernel boot option can be used to
1473 disable the use of MSI interrupts system-wide.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001474 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
Randy Dunlapa9913042005-10-23 12:57:11 -07001475 routing table. These calls are known to be buggy
1476 on several machines and they hang the machine
1477 when used, but on other computers it's the only
1478 way to get the interrupt routing table. Try
1479 this option if the kernel is unable to allocate
1480 IRQs or discover secondary PCI buses on your
1481 motherboard.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001482 rom [X86-32] Assign address space to expansion ROMs.
Randy Dunlapa9913042005-10-23 12:57:11 -07001483 Use with caution as certain devices share
1484 address decoders between ROMs and other
1485 resources.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001486 irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be
Randy Dunlapa9913042005-10-23 12:57:11 -07001487 assigned automatically to PCI devices. You can
1488 make the kernel exclude IRQs of your ISA cards
1489 this way.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001490 pirqaddr=0xAAAAA [X86-32] Specify the physical address
Randy Dunlapa9913042005-10-23 12:57:11 -07001491 of the PIRQ table (normally generated
1492 by the BIOS) if it is outside the
1493 F0000h-100000h range.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001494 lastbus=N [X86-32] Scan all buses thru bus #N. Can be
Randy Dunlapa9913042005-10-23 12:57:11 -07001495 useful if the kernel is unable to find your
1496 secondary buses and you want to tell it
1497 explicitly which ones they are.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001498 assign-busses [X86-32] Always assign all PCI bus
Randy Dunlapa9913042005-10-23 12:57:11 -07001499 numbers ourselves, overriding
1500 whatever the firmware may have done.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001501 usepirqmask [X86-32] Honor the possible IRQ mask stored
Randy Dunlapa9913042005-10-23 12:57:11 -07001502 in the BIOS $PIR table. This is needed on
1503 some systems with broken BIOSes, notably
1504 some HP Pavilion N5400 and Omnibook XE3
1505 notebooks. This will have no effect if ACPI
1506 IRQ routing is enabled.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001507 noacpi [X86-32] Do not use ACPI for IRQ routing
Randy Dunlapa9913042005-10-23 12:57:11 -07001508 or for PCI scanning.
Gary Hade62f420f2007-10-03 15:56:51 -07001509 use_crs [X86-32] Use _CRS for PCI resource
1510 allocation.
Randy Dunlapa9913042005-10-23 12:57:11 -07001511 routeirq Do IRQ routing for all PCI devices.
1512 This is normally done in pci_enable_device(),
1513 so this option is a temporary workaround
1514 for broken drivers that don't call it.
1515 firmware [ARM] Do not re-enumerate the bus but instead
1516 just use the configuration from the
1517 bootloader. This is currently used on
1518 IXP2000 systems where the bus has to be
1519 configured a certain way for adjunct CPUs.
Andi Kleen0637a702006-09-26 10:52:41 +02001520 noearly [X86] Don't do any early type 1 scanning.
1521 This might help on some broken boards which
1522 machine check when some devices' config space
1523 is read. But various workarounds are disabled
1524 and some IOMMU drivers will not work.
Matt Domsch6b4b78f2006-09-29 15:23:23 -05001525 bfsort Sort PCI devices into breadth-first order.
1526 This sorting is done to get a device
1527 order compatible with older (<= 2.4) kernels.
1528 nobfsort Don't sort PCI devices into breadth-first order.
Atsushi Nemoto4516a612007-02-05 16:36:06 -08001529 cbiosize=nn[KMG] The fixed amount of bus space which is
1530 reserved for the CardBus bridge's IO window.
1531 The default value is 256 bytes.
1532 cbmemsize=nn[KMG] The fixed amount of bus space which is
1533 reserved for the CardBus bridge's memory
1534 window. The default value is 64 megabytes.
Matt Domsch6b4b78f2006-09-29 15:23:23 -05001535
Linus Torvalds1da177e2005-04-16 15:20:36 -07001536 pcmv= [HW,PCMCIA] BadgePAD 4
1537
1538 pd. [PARIDE]
1539 See Documentation/paride.txt.
1540
1541 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1542 boot time.
1543 Format: { 0 | 1 }
1544 See arch/parisc/kernel/pdc_chassis.c
1545
1546 pf. [PARIDE]
1547 See Documentation/paride.txt.
1548
1549 pg. [PARIDE]
1550 See Documentation/paride.txt.
1551
1552 pirq= [SMP,APIC] Manual mp-table setup
1553 See Documentation/i386/IO-APIC.txt.
1554
1555 plip= [PPT,NET] Parallel port network link
1556 Format: { parport<nr> | timid | 0 }
1557 See also Documentation/parport.txt.
1558
1559 pnpacpi= [ACPI]
1560 { off }
1561
1562 pnpbios= [ISAPNP]
1563 { on | off | curr | res | no-curr | no-res }
1564
1565 pnp_reserve_irq=
1566 [ISAPNP] Exclude IRQs for the autoconfiguration
1567
1568 pnp_reserve_dma=
1569 [ISAPNP] Exclude DMAs for the autoconfiguration
1570
1571 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
Randy Dunlapa9913042005-10-23 12:57:11 -07001572 Ranges are in pairs (I/O port base and size).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573
1574 pnp_reserve_mem=
Randy Dunlapa9913042005-10-23 12:57:11 -07001575 [ISAPNP] Exclude memory regions for the
1576 autoconfiguration.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001577 Ranges are in pairs (memory base and size).
1578
Ingo Molnar45807a12007-07-15 23:40:10 -07001579 print-fatal-signals=
1580 [KNL] debug: print fatal signals
1581 print-fatal-signals=1: print segfault info to
1582 the kernel console.
1583 default: off.
1584
Randy Dunlape84845c2007-07-15 23:40:25 -07001585 printk.time= Show timing data prefixed to each printk message line
1586 Format: <bool> (1/Y/y=enable, 0/N/n=disable)
1587
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588 profile= [KNL] Enable kernel profiling via /proc/profile
Randy Dunlapa9913042005-10-23 12:57:11 -07001589 Format: [schedule,]<number>
1590 Param: "schedule" - profile schedule points.
1591 Param: <number> - step/bucket size as a power of 2 for
1592 statistical time based profiling.
Mel Gormanb3da2a72007-10-24 18:23:50 +02001593 Param: "sleep" - profile D-state sleeping (millisecs).
1594 Requires CONFIG_SCHEDSTATS
Dave Jonesc0fe2e62007-10-20 03:08:22 +02001595 Param: "kvm" - profile VM exits.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001596
Randy Dunlapa9913042005-10-23 12:57:11 -07001597 processor.max_cstate= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001598 Limit processor to maximum C-state
1599 max_cstate=9 overrides any DMI blacklist limit.
1600
Len Brown41c0d862005-12-28 12:43:51 -05001601 processor.nocst [HW,ACPI]
1602 Ignore the _CST method to determine C-states,
1603 instead using the legacy FADT method
1604
Linus Torvalds1da177e2005-04-16 15:20:36 -07001605 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1606 before loading.
1607 See Documentation/ramdisk.txt.
1608
Randy Dunlapa9913042005-10-23 12:57:11 -07001609 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1610 probe for; one of (bare|imps|exps|lifebook|any).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001611 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1612 per second.
Randy Dunlapa9913042005-10-23 12:57:11 -07001613 psmouse.resetafter= [HW,MOUSE]
1614 Try to reset the device after so many bad packets
Linus Torvalds1da177e2005-04-16 15:20:36 -07001615 (0 = never).
1616 psmouse.resolution=
1617 [HW,MOUSE] Set desired mouse resolution, in dpi.
1618 psmouse.smartscroll=
Randy Dunlapa9913042005-10-23 12:57:11 -07001619 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 0 = disabled, 1 = enabled (default).
1621
1622 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
Randy Dunlapa9913042005-10-23 12:57:11 -07001623 Format:
1624 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625
1626 pt. [PARIDE]
1627 See Documentation/paride.txt.
1628
Kay Sieversdc8c8582007-08-15 12:25:38 +02001629 pty.legacy_count=
1630 [KNL] Number of legacy pty's. Overwrites compiled-in
1631 default number.
1632
Randy Dunlap7d2c5022006-09-29 02:01:02 -07001633 quiet [KNL] Disable most log messages
Randy Dunlapa9913042005-10-23 12:57:11 -07001634
Linus Torvalds1da177e2005-04-16 15:20:36 -07001635 r128= [HW,DRM]
1636
1637 raid= [HW,RAID]
1638 See Documentation/md.txt.
1639
Randy Dunlapa9913042005-10-23 12:57:11 -07001640 ramdisk_blocksize= [RAM]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641 See Documentation/ramdisk.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -07001642
Linus Torvalds1da177e2005-04-16 15:20:36 -07001643 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
Linus Torvalds1da177e2005-04-16 15:20:36 -07001644 See Documentation/ramdisk.txt.
1645
Robert P. J. Day24aaef82008-02-03 15:20:26 +02001646 rcupdate.blimit= [KNL,BOOT]
1647 Set maximum number of finished RCU callbacks to process
1648 in one batch.
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001649
Robert P. J. Day24aaef82008-02-03 15:20:26 +02001650 rcupdate.qhimark= [KNL,BOOT]
1651 Set threshold of queued
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001652 RCU callbacks over which batch limiting is disabled.
1653
Robert P. J. Day24aaef82008-02-03 15:20:26 +02001654 rcupdate.qlowmark= [KNL,BOOT]
1655 Set threshold of queued RCU callbacks below which
1656 batch limiting is re-enabled.
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001657
Olof Johanssonffdfc402005-09-06 15:17:19 -07001658 rdinit= [KNL]
1659 Format: <full_path>
1660 Run specified binary instead of /init from the ramdisk,
1661 used for early userspace startup. See initrd.
1662
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001663 reboot= [BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 Format: <reboot_mode>[,<reboot_mode2>[,...]]
Mauro Carvalho Chehabe53dd082007-09-15 07:38:47 -03001665 See arch/*/kernel/reboot.c or arch/*/kernel/process.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666
1667 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1668
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001669 reservetop= [X86-32]
Zachary Amsden461a9af2006-09-25 23:32:25 -07001670 Format: nn[KMG]
1671 Reserves a hole at the top of the kernel virtual
1672 address space.
1673
Vivek Goyal7e962872006-09-27 01:50:44 -07001674 reset_devices [KNL] Force drivers to reset the underlying device
1675 during initialization.
1676
Randy Dunlapa9913042005-10-23 12:57:11 -07001677 resume= [SWSUSP]
1678 Specify the partition device for software suspend
Linus Torvalds1da177e2005-04-16 15:20:36 -07001679
Rafael J. Wysockiecbd0da2006-12-06 20:34:13 -08001680 resume_offset= [SWSUSP]
1681 Specify the offset from the beginning of the partition
1682 given by "resume=" at which the swap header is located,
1683 in <PAGE_SIZE> units (needed only for swap files).
1684 See Documentation/power/swsusp-and-swap-files.txt
1685
Michael Neuling0a7b35cb2007-02-10 01:44:33 -08001686 retain_initrd [RAM] Keep initrd memory after extraction
1687
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688 rhash_entries= [KNL,NET]
1689 Set number of hash buckets for route cache
1690
1691 riscom8= [HW,SERIAL]
1692 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1693
1694 ro [KNL] Mount root device read-only on boot
1695
1696 root= [KNL] Root filesystem
1697
1698 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1699 mount the root filesystem
1700
1701 rootflags= [KNL] Set root filesystem mount option string
1702
1703 rootfstype= [KNL] Set root filesystem type
1704
Pierre Ossmancc1ed752007-07-15 23:40:35 -07001705 rootwait [KNL] Wait (indefinitely) for root device to show up.
1706 Useful for devices that are detected asynchronously
1707 (e.g. USB and MMC devices).
1708
James Morris20510f22007-10-16 23:31:32 -07001709 root_plug.vendor_id=
1710 [ROOTPLUG] Override the default vendor ID
1711
1712 root_plug.product_id=
1713 [ROOTPLUG] Override the default product ID
1714
1715 root_plug.debug=
1716 [ROOTPLUG] Enable debugging output
1717
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718 rw [KNL] Mount root device read-write on boot
1719
1720 S [KNL] Run init in single mode
1721
1722 sa1100ir [NET]
1723 See drivers/net/irda/sa1100_ir.c.
1724
Linus Torvalds1da177e2005-04-16 15:20:36 -07001725 sbni= [NET] Granch SBNI12 leased line adapter
Randy Dunlapa9913042005-10-23 12:57:11 -07001726
Linus Torvalds1da177e2005-04-16 15:20:36 -07001727 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1728 Format: <io>[,<timeout>[,<isapnp>]]
1729
1730 scsi_debug_*= [SCSI]
1731 See drivers/scsi/scsi_debug.c.
1732
1733 scsi_default_dev_flags=
1734 [SCSI] SCSI default device flags
1735 Format: <integer>
1736
1737 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1738 Format: <vendor>:<model>:<flags>
1739 (flags are integer value)
1740
Randy Dunlap6af66322007-11-14 16:52:25 -08001741 scsi_logging_level= [SCSI] a bit mask of logging levels
1742 See drivers/scsi/scsi_logging.h for bits. Also
1743 settable via sysctl at dev.scsi.logging_level
1744 (/proc/sys/dev/scsi/logging_level).
1745 There is also a nice 'scsi_logging_level' script in the
1746 S390-tools package, available for download at
1747 http://www-128.ibm.com/developerworks/linux/linux390/s390-tools-1.5.4.html
Linus Torvalds1da177e2005-04-16 15:20:36 -07001748
Matthew Wilcox3e082a92006-09-28 15:19:20 -06001749 scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are
1750 discovered. async scans them in kernel threads,
1751 allowing boot to proceed. none ignores them, expecting
1752 user space to do the scan.
1753
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 selinux [SELINUX] Disable or enable SELinux at boot time.
1755 Format: { "0" | "1" }
1756 See security/selinux/Kconfig help text.
1757 0 -- disable.
1758 1 -- enable.
1759 Default value is set via kernel config option.
1760 If enabled at boot time, /selinux/disable can be used
1761 later to disable prior to initial policy load.
1762
James Morris4e5ab4c2006-06-09 00:33:33 -07001763 selinux_compat_net =
1764 [SELINUX] Set initial selinux_compat_net flag value.
Mauro Carvalho Chehabe53dd082007-09-15 07:38:47 -03001765 Format: { "0" | "1" }
1766 0 -- use new secmark-based packet controls
1767 1 -- use legacy packet controls
1768 Default value is 0 (preferred).
1769 Value can be changed at runtime via
1770 /selinux/compat_net.
James Morris4e5ab4c2006-06-09 00:33:33 -07001771
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001772 serialnumber [BUGS=X86-32]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001773
Linus Torvalds1da177e2005-04-16 15:20:36 -07001774 shapers= [NET]
1775 Maximal number of shapers.
Randy Dunlapa9913042005-10-23 12:57:11 -07001776
Linus Torvalds1da177e2005-04-16 15:20:36 -07001777 sim710= [SCSI,HW]
1778 See header of drivers/scsi/sim710.c.
1779
1780 simeth= [IA-64]
1781 simscsi=
Randy Dunlapa9913042005-10-23 12:57:11 -07001782
Linus Torvalds1da177e2005-04-16 15:20:36 -07001783 slram= [HW,MTD]
1784
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001785 slub_debug[=options[,slabs]] [MM, SLUB]
1786 Enabling slub_debug allows one to determine the
1787 culprit if slab objects become corrupted. Enabling
1788 slub_debug can create guard zones around objects and
1789 may poison objects when not in use. Also tracks the
1790 last alloc / free. For more information see
1791 Documentation/vm/slub.txt.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001792
1793 slub_max_order= [MM, SLUB]
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001794 Determines the maximum allowed order for slabs.
1795 A high setting may cause OOMs due to memory
1796 fragmentation. For more information see
1797 Documentation/vm/slub.txt.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001798
1799 slub_min_objects= [MM, SLUB]
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001800 The minimum number of objects per slab. SLUB will
1801 increase the slab order up to slub_max_order to
1802 generate a sufficiently large slab able to contain
1803 the number of objects indicated. The higher the number
1804 of objects the smaller the overhead of tracking slabs
1805 and the less frequently locks need to be acquired.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001806 For more information see Documentation/vm/slub.txt.
1807
1808 slub_min_order= [MM, SLUB]
1809 Determines the mininum page order for slabs. Must be
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001810 lower than slub_max_order.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001811 For more information see Documentation/vm/slub.txt.
1812
1813 slub_nomerge [MM, SLUB]
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001814 Disable merging of slabs with similar size. May be
Christoph Lameterc1aee212007-05-31 00:40:47 -07001815 necessary if there is some reason to distinguish
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001816 allocs to different slabs. Debug options disable
1817 merging on their own.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001818 For more information see Documentation/vm/slub.txt.
1819
Linus Torvalds1da177e2005-04-16 15:20:36 -07001820 smart2= [HW]
1821 Format: <io1>[,<io2>[,...,<io8>]]
1822
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001823 smp-alt-once [X86-32,SMP] On a hotplug CPU system, only
Jeremy Fitzhardingeb7fb4af2007-05-02 19:27:13 +02001824 attempt to substitute SMP alternatives once at boot.
1825
Bjorn Helgaasd0d4f692007-05-08 00:36:05 -07001826 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
1827 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
1828 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
1829 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
1830 smsc-ircc2.ircc_irq= [HW] IRQ line
1831 smsc-ircc2.ircc_dma= [HW] DMA channel
1832 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
1833 0: Toshiba Satellite 1800 (GP data pin select)
1834 1: Fast pin select (default)
1835 2: ATC IRMode
1836
Linus Torvalds1da177e2005-04-16 15:20:36 -07001837 snd-ad1816a= [HW,ALSA]
1838
1839 snd-ad1848= [HW,ALSA]
1840
1841 snd-ali5451= [HW,ALSA]
1842
1843 snd-als100= [HW,ALSA]
1844
1845 snd-als4000= [HW,ALSA]
1846
1847 snd-azt2320= [HW,ALSA]
1848
1849 snd-cmi8330= [HW,ALSA]
1850
1851 snd-cmipci= [HW,ALSA]
1852
1853 snd-cs4231= [HW,ALSA]
1854
1855 snd-cs4232= [HW,ALSA]
1856
1857 snd-cs4236= [HW,ALSA]
1858
1859 snd-cs4281= [HW,ALSA]
1860
1861 snd-cs46xx= [HW,ALSA]
1862
1863 snd-dt019x= [HW,ALSA]
1864
1865 snd-dummy= [HW,ALSA]
1866
1867 snd-emu10k1= [HW,ALSA]
1868
1869 snd-ens1370= [HW,ALSA]
1870
1871 snd-ens1371= [HW,ALSA]
1872
1873 snd-es968= [HW,ALSA]
1874
1875 snd-es1688= [HW,ALSA]
1876
1877 snd-es18xx= [HW,ALSA]
1878
1879 snd-es1938= [HW,ALSA]
1880
1881 snd-es1968= [HW,ALSA]
1882
1883 snd-fm801= [HW,ALSA]
1884
1885 snd-gusclassic= [HW,ALSA]
1886
1887 snd-gusextreme= [HW,ALSA]
1888
1889 snd-gusmax= [HW,ALSA]
1890
1891 snd-hdsp= [HW,ALSA]
1892
1893 snd-ice1712= [HW,ALSA]
1894
1895 snd-intel8x0= [HW,ALSA]
1896
1897 snd-interwave= [HW,ALSA]
1898
1899 snd-interwave-stb=
1900 [HW,ALSA]
1901
1902 snd-korg1212= [HW,ALSA]
1903
1904 snd-maestro3= [HW,ALSA]
1905
1906 snd-mpu401= [HW,ALSA]
1907
1908 snd-mtpav= [HW,ALSA]
1909
1910 snd-nm256= [HW,ALSA]
1911
1912 snd-opl3sa2= [HW,ALSA]
1913
1914 snd-opti92x-ad1848=
1915 [HW,ALSA]
1916
1917 snd-opti92x-cs4231=
1918 [HW,ALSA]
1919
1920 snd-opti93x= [HW,ALSA]
1921
1922 snd-pmac= [HW,ALSA]
1923
1924 snd-rme32= [HW,ALSA]
1925
1926 snd-rme96= [HW,ALSA]
1927
1928 snd-rme9652= [HW,ALSA]
1929
1930 snd-sb8= [HW,ALSA]
1931
1932 snd-sb16= [HW,ALSA]
1933
1934 snd-sbawe= [HW,ALSA]
1935
1936 snd-serial= [HW,ALSA]
1937
1938 snd-sgalaxy= [HW,ALSA]
1939
1940 snd-sonicvibes= [HW,ALSA]
1941
1942 snd-sun-amd7930=
1943 [HW,ALSA]
1944
1945 snd-sun-cs4231= [HW,ALSA]
1946
1947 snd-trident= [HW,ALSA]
1948
1949 snd-usb-audio= [HW,ALSA,USB]
1950
1951 snd-via82xx= [HW,ALSA]
1952
1953 snd-virmidi= [HW,ALSA]
1954
1955 snd-wavefront= [HW,ALSA]
1956
1957 snd-ymfpci= [HW,ALSA]
Randy Dunlapa9913042005-10-23 12:57:11 -07001958
Linus Torvalds1da177e2005-04-16 15:20:36 -07001959 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1960 See Documentation/sonypi.txt
1961
1962 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1963 See Documentation/specialix.txt.
1964
1965 spia_io_base= [HW,MTD]
1966 spia_fio_base=
1967 spia_pedr=
1968 spia_peddr=
1969
1970 sscape= [HW,OSS]
1971 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
Randy Dunlapa9913042005-10-23 12:57:11 -07001972
Linus Torvalds1da177e2005-04-16 15:20:36 -07001973 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1974 See Documentation/scsi/st.txt.
1975
Linus Torvalds1da177e2005-04-16 15:20:36 -07001976 sti= [PARISC,HW]
1977 Format: <num>
1978 Set the STI (builtin display/keyboard on the HP-PARISC
1979 machines) console (graphic card) which should be used
1980 as the initial boot-console.
1981 See also comment in drivers/video/console/sticore.c.
1982
1983 sti_font= [HW]
1984 See comment in drivers/video/console/sticore.c.
1985
1986 stifb= [HW]
1987 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1988
Greg Banks42a7fc42007-03-06 01:42:23 -08001989 sunrpc.pool_mode=
1990 [NFS]
1991 Control how the NFS server code allocates CPUs to
1992 service thread pools. Depending on how many NICs
1993 you have and where their interrupts are bound, this
1994 option will affect which CPUs will do NFS serving.
1995 Note: this parameter cannot be changed while the
1996 NFS server is running.
1997
1998 auto the server chooses an appropriate mode
1999 automatically using heuristics
2000 global a single global pool contains all CPUs
2001 percpu one pool for each CPU
2002 pernode one pool for each NUMA node (equivalent
2003 to global on non-NUMA machines)
2004
Linus Torvalds1da177e2005-04-16 15:20:36 -07002005 swiotlb= [IA-64] Number of I/O TLB slabs
Randy Dunlapa9913042005-10-23 12:57:11 -07002006
Linus Torvalds1da177e2005-04-16 15:20:36 -07002007 switches= [HW,M68k]
2008
2009 sym53c416= [HW,SCSI]
2010 See header of drivers/scsi/sym53c416.c.
2011
Ingo Molnar5d6f6472006-12-13 00:34:36 -08002012 sysrq_always_enabled
2013 [KNL]
2014 Ignore sysrq setting - this boot parameter will
2015 neutralize any effect of /proc/sys/kernel/sysrq.
2016 Useful for debugging.
2017
Linus Torvalds1da177e2005-04-16 15:20:36 -07002018 t128= [HW,SCSI]
2019 See header of drivers/scsi/t128.c.
2020
2021 tdfx= [HW,DRM]
2022
2023 thash_entries= [KNL,NET]
2024 Set number of hash buckets for TCP connection
2025
Len Brownf8707ec2007-08-12 00:12:54 -04002026 thermal.act= [HW,ACPI]
2027 -1: disable all active trip points in all thermal zones
2028 <degrees C>: override all lowest active trip points
2029
Len Brownc52a7412007-08-14 15:49:32 -04002030 thermal.crt= [HW,ACPI]
2031 -1: disable all critical trip points in all thermal zones
2032 <degrees C>: lower all critical trip points
2033
Len Brownf5487142007-08-12 00:12:44 -04002034 thermal.nocrt= [HW,ACPI]
2035 Set to disable actions on ACPI thermal zone
2036 critical and hot trip points.
2037
Len Brown72b33ef2007-08-12 00:12:17 -04002038 thermal.off= [HW,ACPI]
2039 1: disable ACPI thermal control
2040
Len Browna70cdc52007-08-12 00:12:35 -04002041 thermal.psv= [HW,ACPI]
2042 -1: disable all passive trip points
2043 <degrees C>: override all passive trip points to this value
2044
Len Brown730ff342007-08-12 00:12:26 -04002045 thermal.tzp= [HW,ACPI]
2046 Specify global default ACPI thermal zone polling rate
2047 <deci-seconds>: poll all this frequency
2048 0: no polling (default)
2049
Linus Torvalds1da177e2005-04-16 15:20:36 -07002050 tipar.timeout= [HW,PPT]
2051 Set communications timeout in tenths of a second
2052 (default 15).
2053
2054 tipar.delay= [HW,PPT]
2055 Set inter-bit delay in microseconds (default 10).
2056
Linus Torvalds1da177e2005-04-16 15:20:36 -07002057 tmscsim= [HW,SCSI]
2058 See comment before function dc390_setup() in
2059 drivers/scsi/tmscsim.c.
2060
2061 tp720= [HW,PS2]
2062
2063 trix= [HW,OSS] MediaTrix AudioTrix Pro
Randy Dunlapa9913042005-10-23 12:57:11 -07002064 Format:
2065 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
2066
Randy Dunlapa9913042005-10-23 12:57:11 -07002067 turbografx.map[2|3]= [HW,JOY]
2068 TurboGraFX parallel port interface
2069 Format:
2070 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
Linus Torvalds1da177e2005-04-16 15:20:36 -07002071 See also Documentation/input/joystick-parport.txt
2072
2073 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
2074 See header of drivers/scsi/u14-34f.c.
2075
2076 uart401= [HW,OSS]
2077 Format: <io>,<irq>
2078
2079 uart6850= [HW,OSS]
2080 Format: <io>,<irq>
2081
Alan Stern5f8364b2006-12-05 16:29:55 -05002082 uhci-hcd.ignore_oc=
2083 [USB] Ignore overcurrent events (default N).
2084 Some badly-designed motherboards generate lots of
2085 bogus events, for ports that aren't wired to
2086 anything. Set this parameter to avoid log spamming.
2087 Note that genuine overcurrent events won't be
2088 reported either.
2089
Alan Sternb5e795f2007-02-20 15:00:53 -05002090 usbcore.autosuspend=
2091 [USB] The autosuspend time delay (in seconds) used
2092 for newly-detected USB devices (default 2). This
2093 is the time required before an idle device will be
2094 autosuspended. Devices for which the delay is set
Alan Sterneaafbc32007-03-13 16:39:15 -04002095 to a negative value won't be autosuspended at all.
Alan Sternb5e795f2007-02-20 15:00:53 -05002096
Linus Torvalds1da177e2005-04-16 15:20:36 -07002097 usbhid.mousepoll=
2098 [USBHID] The interval which mice are to be polled at.
Randy Dunlapa9913042005-10-23 12:57:11 -07002099
Alan Coxcd4f0ef2007-07-31 00:37:59 -07002100 vdso= [X86-32,SH,x86-64]
Jeremy Fitzhardinge1dbf527c2007-05-02 19:27:12 +02002101 vdso=2: enable compat VDSO (default with COMPAT_VDSO)
Ingo Molnare6e54942006-06-27 02:53:50 -07002102 vdso=1: enable VDSO (default)
2103 vdso=0: disable VDSO mapping
2104
Roland McGrathaf65d642008-01-30 13:30:43 +01002105 vdso32= [X86-32,X86-64]
2106 vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
2107 vdso32=1: enable 32-bit VDSO (default)
2108 vdso32=0: disable 32-bit VDSO mapping
2109
Yasuaki Ishimatsud080d392007-07-17 21:22:55 +09002110 vector= [IA-64,SMP]
2111 vector=percpu: enable percpu vector domain
2112
Linus Torvalds1da177e2005-04-16 15:20:36 -07002113 video= [FB] Frame buffer configuration
2114 See Documentation/fb/modedb.txt.
2115
Alan Coxcd4f0ef2007-07-31 00:37:59 -07002116 vga= [BOOT,X86-32] Select a particular video mode
Randy Dunlapa9913042005-10-23 12:57:11 -07002117 See Documentation/i386/boot.txt and
2118 Documentation/svga.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002119 Use vga=ask for menu.
2120 This is actually a boot loader parameter; the value is
2121 passed to the kernel using a special protocol.
2122
Randy Dunlapa9913042005-10-23 12:57:11 -07002123 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
Linus Torvalds1da177e2005-04-16 15:20:36 -07002124 size of <nn>. This can be used to increase the
2125 minimum size (128MB on x86). It can also be used to
2126 decrease the size and leave more room for directly
2127 mapped kernel RAM.
2128
Peter Oberparleiter585c3042006-06-29 15:08:25 +02002129 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
2130 Format: <command>
Linus Torvalds1da177e2005-04-16 15:20:36 -07002131
Peter Oberparleiter585c3042006-06-29 15:08:25 +02002132 vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
2133 Format: <command>
2134
2135 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
2136 Format: <command>
Randy Dunlapa9913042005-10-23 12:57:11 -07002137
Linus Torvalds1da177e2005-04-16 15:20:36 -07002138 waveartist= [HW,OSS]
2139 Format: <io>,<irq>,<dma>,<dma2>
Randy Dunlapa9913042005-10-23 12:57:11 -07002140
Linus Torvalds1da177e2005-04-16 15:20:36 -07002141 wd33c93= [HW,SCSI]
2142 See header of drivers/scsi/wd33c93.c.
2143
2144 wd7000= [HW,SCSI]
2145 See header of drivers/scsi/wd7000.c.
2146
2147 wdt= [WDT] Watchdog
Gabriel C8dfe9c22007-08-10 13:01:00 -07002148 See Documentation/watchdog/wdt.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002149
2150 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
2151 xd_geo= See header of drivers/block/xd.c.
2152
2153 xirc2ps_cs= [NET,PCMCIA]
Randy Dunlapa9913042005-10-23 12:57:11 -07002154 Format:
2155 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
Linus Torvalds1da177e2005-04-16 15:20:36 -07002156
Andi Kleena62eaf12006-02-16 23:41:58 +01002157 norandmaps Don't use address space randomization
2158 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
2159
Randy Dunlapa9913042005-10-23 12:57:11 -07002160______________________________________________________________________
Linus Torvalds1da177e2005-04-16 15:20:36 -07002161
2162TODO:
2163
2164 Add documentation for ALSA options.
2165 Add more DRM drivers.