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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
Rafael J. Wysockid8f3de02008-06-12 23:24:06 +0200150 Format: { s3_bios, s3_mode, s3_beep, old_ordering }
Pavel Machek23b168d2008-02-05 19:27:12 +0100151 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.
Rafael J. Wysockid8f3de02008-06-12 23:24:06 +0200154 old_ordering causes the ACPI 1.0 ordering of the _PTS
155 control method, wrt putting devices into low power
156 states, to be enforced (the ACPI 2.0 ordering of _PTS is
157 used by default).
Randy Dunlapa9913042005-10-23 12:57:11 -0700158
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Randy Dunlapa9913042005-10-23 12:57:11 -0700160 Format: { level | edge | high | low }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161
Randy Dunlapa9913042005-10-23 12:57:11 -0700162 acpi_irq_balance [HW,ACPI]
163 ACPI will balance active IRQs
164 default in APIC mode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
Randy Dunlapa9913042005-10-23 12:57:11 -0700166 acpi_irq_nobalance [HW,ACPI]
167 ACPI will not move active IRQs (default)
168 default in PIC mode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169
Randy Dunlapa9913042005-10-23 12:57:11 -0700170 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
171 use by PCI
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 Format: <irq>,<irq>...
173
Randy Dunlapa9913042005-10-23 12:57:11 -0700174 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 Format: <irq>,<irq>...
176
Len Brown67effe82007-07-26 00:50:06 -0400177 acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
178
Len Browna1f9e652006-01-25 23:47:36 -0500179 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
180 Format: To spoof as Windows 98: ="Microsoft Windows"
181
Len Brownae00d812007-05-29 18:43:33 -0400182 acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
183 acpi_osi="string1" # add string1 -- only one string
184 acpi_osi="!string2" # remove built-in string2
185 acpi_osi= # disable all strings
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186
187 acpi_serialize [HW,ACPI] force serialization of AML methods
188
189 acpi_skip_timer_override [HW,ACPI]
190 Recognize and ignore IRQ0/pin2 Interrupt Override.
191 For broken nForce2 BIOS resulting in XT-PIC timer.
Andi Kleenfa18f472006-11-14 16:57:46 +0100192 acpi_use_timer_override [HW,ACPI}
193 Use timer override. For some broken Nvidia NF5 boards
194 that require a timer override, but don't have
195 HPET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196
Zhang Ruif9891062007-04-24 13:53:22 +0800197 acpi.debug_layer= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 Format: <int>
Randy Dunlapa9913042005-10-23 12:57:11 -0700199 Each bit of the <int> indicates an ACPI debug layer,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 1: enable, 0: disable. It is useful for boot time
201 debugging. After system has booted up, it can be set
Zhang Ruif9891062007-04-24 13:53:22 +0800202 via /sys/module/acpi/parameters/debug_layer.
203 CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
204 Available bits (add the numbers together) to enable debug output
205 for specific parts of the ACPI subsystem:
206 0x01 utilities 0x02 hardware 0x04 events 0x08 tables
207 0x10 namespace 0x20 parser 0x40 dispatcher
208 0x80 executer 0x100 resources 0x200 acpica debugger
209 0x400 os services 0x800 acpica disassembler.
210 The number can be in decimal or prefixed with 0x in hex.
211 Warning: Many of these options can produce a lot of
212 output and make your system unusable. Be very careful.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
Zhang Ruif9891062007-04-24 13:53:22 +0800214 acpi.debug_level= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 Format: <int>
Randy Dunlapa9913042005-10-23 12:57:11 -0700216 Each bit of the <int> indicates an ACPI debug level,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 1: enable, 0: disable. It is useful for boot time
218 debugging. After system has booted up, it can be set
Zhang Ruif9891062007-04-24 13:53:22 +0800219 via /sys/module/acpi/parameters/debug_level.
220 CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
221 Available bits (add the numbers together) to enable different
222 debug output levels of the ACPI subsystem:
223 0x01 error 0x02 warn 0x04 init 0x08 debug object
224 0x10 info 0x20 init names 0x40 parse 0x80 load
225 0x100 dispatch 0x200 execute 0x400 names 0x800 operation region
226 0x1000 bfield 0x2000 tables 0x4000 values 0x8000 objects
227 0x10000 resources 0x20000 user requests 0x40000 package.
228 The number can be in decimal or prefixed with 0x in hex.
229 Warning: Many of these options can produce a lot of
230 output and make your system unusable. Be very careful.
231
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700232 acpi_pm_good [X86-32,X86-64]
john stultz5d0cf412006-06-26 00:25:12 -0700233 Override the pmtimer bug detection: force the kernel
234 to assume that this machine's pmtimer latches its value
235 and always returns good values.
236
Chuck Ebbertc99c1082007-07-27 10:46:20 +1000237 agp= [AGP]
238 { off | try_unsupported }
239 off: disable AGP support
240 try_unsupported: try to drive unsupported chipsets
241 (may crash computer or cause data corruption)
242
Chuck Ebbert66759a02005-09-12 18:49:25 +0200243 enable_timer_pin_1 [i386,x86-64]
244 Enable PIN 1 of APIC timer
Randy Dunlapa9913042005-10-23 12:57:11 -0700245 Can be useful to work around chipset bugs
246 (in particular on some ATI chipsets).
Chuck Ebbert66759a02005-09-12 18:49:25 +0200247 The kernel tries to set a reasonable default.
248
249 disable_timer_pin_1 [i386,x86-64]
250 Disable PIN 1 of APIC timer
251 Can be useful to work around chipset bugs.
252
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 ad1848= [HW,OSS]
254 Format: <io>,<irq>,<dma>,<dma2>,<type>
255
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 advansys= [HW,SCSI]
257 See header of drivers/scsi/advansys.c.
258
259 advwdt= [HW,WDT] Advantech WDT
260 Format: <iostart>,<iostop>
261
262 aedsp16= [HW,OSS] Audio Excel DSP 16
263 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
264 See also header of sound/oss/aedsp16.c.
Randy Dunlapa9913042005-10-23 12:57:11 -0700265
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 aha152x= [HW,SCSI]
267 See Documentation/scsi/aha152x.txt.
268
269 aha1542= [HW,SCSI]
270 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
271
272 aic7xxx= [HW,SCSI]
273 See Documentation/scsi/aic7xxx.txt.
274
275 aic79xx= [HW,SCSI]
276 See Documentation/scsi/aic79xx.txt.
277
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 amijoy.map= [HW,JOY] Amiga joystick support
279 Map of devices attached to JOY0DAT and JOY1DAT
280 Format: <a>,<b>
281 See also Documentation/kernel/input/joystick.txt
282
283 analog.map= [HW,JOY] Analog joystick and gamepad support
284 Specifies type or capabilities of an analog joystick
285 connected to one of 16 gameports
286 Format: <type1>,<type2>,..<type16>
287
Randy Dunlapa9913042005-10-23 12:57:11 -0700288 apc= [HW,SPARC]
289 Power management functions (SPARCstation-4/5 + deriv.)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 Format: noidle
291 Disable APC CPU standby support. SPARCstation-Fox does
292 not play well with APC CPU idle - disable it if you have
293 APC and your system crashes randomly.
294
Randy Dunlapc8facbb2007-07-31 00:37:40 -0700295 apic= [APIC,i386] Advanced Programmable Interrupt Controller
296 Change the output verbosity whilst booting
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 Format: { quiet (default) | verbose | debug }
298 Change the amount of debugging information output
299 when initialising the APIC and IO-APIC components.
Randy Dunlapa9913042005-10-23 12:57:11 -0700300
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 apm= [APM] Advanced Power Management
302 See header of arch/i386/kernel/apm.c.
303
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
305 Format: <io>,<irq>,<nodeID>
306
307 ataflop= [HW,M68k]
308
309 atarimouse= [HW,MOUSE] Atari Mouse
310
311 atascsi= [HW,SCSI] Atari SCSI
312
313 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
314 EzKey and similar keyboards
315
316 atkbd.reset= [HW] Reset keyboard during initialization
317
Randy Dunlapa9913042005-10-23 12:57:11 -0700318 atkbd.set= [HW] Select keyboard code set
319 Format: <int> (2 = AT (default), 3 = PS/2)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320
321 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
322 keyboards
323
324 atkbd.softraw= [HW] Choose between synthetic and real raw mode
325 Format: <bool> (0 = real, 1 = synthetic (default))
Randy Dunlapa9913042005-10-23 12:57:11 -0700326
327 atkbd.softrepeat= [HW]
328 Use software keyboard repeat
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329
330 autotest [IA64]
331
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 baycom_epp= [HW,AX25]
333 Format: <io>,<mode>
Randy Dunlapa9913042005-10-23 12:57:11 -0700334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
336 Format: <io>,<mode>
337 See header of drivers/net/hamradio/baycom_par.c.
338
Randy Dunlapa9913042005-10-23 12:57:11 -0700339 baycom_ser_fdx= [HW,AX25]
340 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 Format: <io>,<irq>,<mode>[,<baud>]
342 See header of drivers/net/hamradio/baycom_ser_fdx.c.
343
Randy Dunlapa9913042005-10-23 12:57:11 -0700344 baycom_ser_hdx= [HW,AX25]
345 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 Format: <io>,<irq>,<mode>
347 See header of drivers/net/hamradio/baycom_ser_hdx.c.
348
Randy Dunlapbfe8df32007-10-16 01:23:46 -0700349 boot_delay= Milliseconds to delay each printk during boot.
350 Values larger than 10 seconds (10000) are changed to
351 no delay (0).
352 Format: integer
353
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
Randy Dunlapa9913042005-10-23 12:57:11 -0700355 bttv.radio= Most important insmod options are available as
356 kernel args too.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
358 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
359
360 BusLogic= [HW,SCSI]
361 See drivers/scsi/BusLogic.c, comment before function
362 BusLogic_ParseDriverOptions().
363
364 c101= [NET] Moxa C101 synchronous serial card
365
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700366 cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 Sometimes CPU hardware bugs make them report the cache
368 size incorrectly. The kernel will attempt work arounds
369 to fix known problems, but for some CPUs it is not
370 possible to determine what the correct size should be.
371 This option provides an override for these situations.
372
Ahmed S. Darwish076c54c2008-03-06 18:09:10 +0200373 security= [SECURITY] Choose a security module to enable at boot.
374 If this boot parameter is not specified, only the first
375 security module asking for security registration will be
376 loaded. An invalid security module name will be treated
377 as if no module has been chosen.
378
James Morris20510f22007-10-16 23:31:32 -0700379 capability.disable=
380 [SECURITY] Disable capabilities. This would normally
381 be used only if an alternative security model is to be
382 configured. Potentially dangerous and should only be
383 used if you are entirely sure of the consequences.
384
Sebastian Ott14ff56b2008-01-26 14:10:37 +0100385 ccw_timeout_log [S390]
386 See Documentation/s390/CommonIO for details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
Paul Menage8bab8dd2008-04-04 14:29:57 -0700388 cgroup_disable= [KNL] Disable a particular controller
389 Format: {name of the controller(s) to disable}
390 {Currently supported controllers - "memory"}
391
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 checkreqprot [SELINUX] Set initial checkreqprot flag value.
393 Format: { "0" | "1" }
394 See security/selinux/Kconfig help text.
Randy Dunlapa9913042005-10-23 12:57:11 -0700395 0 -- check protection applied by kernel (includes
396 any implied execute protection).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 1 -- check protection requested by application.
398 Default value is set via a kernel config option.
Randy Dunlapa9913042005-10-23 12:57:11 -0700399 Value can be changed at runtime via
400 /selinux/checkreqprot.
401
Sebastian Ott661ca0d2008-01-26 14:10:36 +0100402 cio_ignore= [S390]
403 See Documentation/s390/CommonIO for details.
404
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700405 clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
john stultz734efb42006-06-26 00:25:05 -0700406 [Deprecated]
Matt LaPlante3f6dee92006-10-03 22:45:33 +0200407 Forces specified clocksource (if available) to be used
john stultz734efb42006-06-26 00:25:05 -0700408 when calculating gettimeofday(). If specified
Matt LaPlante3f6dee92006-10-03 22:45:33 +0200409 clocksource is not available, it defaults to PIT.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 Format: { pit | tsc | cyclone | pmtmr }
411
Randy Dunlap3d6ac982007-05-23 13:58:16 -0700412 clocksource= [GENERIC_TIME] Override the default clocksource
413 Format: <string>
414 Override the default clocksource and use the clocksource
415 with the name specified.
416 Some clocksource names to choose from, depending on
417 the platform:
418 [all] jiffies (this is the base, fallback clocksource)
419 [ACPI] acpi_pm
420 [ARM] imx_timer1,OSTS,netx_timer,mpu_timer2,
421 pxa_timer,timer3,32k_counter,timer0_1
422 [AVR32] avr32
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700423 [X86-32] pit,hpet,tsc,vmi-timer;
Randy Dunlap3d6ac982007-05-23 13:58:16 -0700424 scx200_hrt on Geode; cyclone on IBM x440
425 [MIPS] MIPS
426 [PARISC] cr16
427 [S390] tod
428 [SH] SuperH
429 [SPARC64] tick
430 [X86-64] hpet,tsc
431
Andi Kleenac72e782008-01-30 13:33:21 +0100432 clearcpuid=BITNUM [X86]
433 Disable CPUID feature X for the kernel. See
434 include/asm-x86/cpufeature.h for the valid bit numbers.
435 Note the Linux specific bits are not necessarily
436 stable over kernel options, but the vendor specific
437 ones should be.
438 Also note that user programs calling CPUID directly
439 or using the feature without checking anything
440 will still see it. This just prevents it from
441 being used by the kernel or shown in /proc/cpuinfo.
442 Also note the kernel might malfunction if you disable
443 some critical bits.
444
Arjan van de Vena25bd942008-01-30 13:33:08 +0100445 code_bytes [IA32/X86_64] How many bytes of object code to print
446 in an oops report.
Chuck Ebbert86c41832007-02-13 13:26:25 +0100447 Range: 0 - 8192
448 Default: 64
449
Andi Kleenf9262c12006-03-08 17:57:25 -0800450 disable_8254_timer
451 enable_8254_timer
452 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
453 over the 8254 in addition to over the IO-APIC. The
454 kernel tries to set a sensible default.
455
Thomas Gleixnerb17530b2007-10-19 20:35:02 +0200456 hpet= [X86-32,HPET] option to control HPET usage
457 Format: { enable (default) | disable | force }
458 disable: disable HPET and use PIT instead
Carlos Corbachod79a5f82007-10-19 18:51:27 +0100459 force: allow force enabled of undocumented chips (ICH4,
460 VIA, nVidia)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 com20020= [HW,NET] ARCnet - COM20020 chipset
Randy Dunlapa9913042005-10-23 12:57:11 -0700463 Format:
464 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465
466 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
467 Format: <io>[,<irq>]
468
Randy Dunlapa9913042005-10-23 12:57:11 -0700469 com90xx= [HW,NET]
470 ARCnet - COM90xx chipset (memory-mapped buffers)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 Format: <io>[,<irq>[,<memstart>]]
472
473 condev= [HW,S390] console device
474 conmode=
Randy Dunlapa9913042005-10-23 12:57:11 -0700475
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 console= [KNL] Output console device and options.
477
478 tty<n> Use the virtual console device <n>.
479
480 ttyS<n>[,options]
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800481 ttyUSB0[,options]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 Use the specified serial port. The options are of
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800483 the form "bbbbpnf", where "bbbb" is the baud rate,
484 "p" is parity ("n", "o", or "e"), "n" is number of
485 bits, and "f" is flow control ("r" for RTS or
486 omit it). Default is "9600n8".
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
Randy Dunlapf1a1c2d2006-03-25 03:08:17 -0800488 See Documentation/serial-console.txt for more
489 information. See
490 Documentation/networking/netconsole.txt for an
491 alternative.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700493 uart[8250],io,<addr>[,options]
494 uart[8250],mmio,<addr>[,options]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 Start an early, polled-mode console on the 8250/16550
496 UART at the specified I/O port or MMIO address,
497 switching to the matching ttyS device later. The
498 options are the same as for ttyS, above.
499
Samuel Thibaultf7511d52008-04-30 00:54:51 -0700500 If the device connected to the port is not a TTY but a braille
501 device, prepend "brl," before the device type, for instance
502 console=brl,ttyS0
503 For now, only VisioBraille is supported.
504
Yinghai Lu18a8bd92007-07-15 23:37:59 -0700505 earlycon= [KNL] Output early console device and options.
506 uart[8250],io,<addr>[,options]
507 uart[8250],mmio,<addr>[,options]
508 Start an early, polled-mode console on the 8250/16550
509 UART at the specified I/O port or MMIO address.
510 The options are the same as for ttyS, above.
511
Andres Salomon8f4ce8c2007-10-18 03:04:50 -0700512 no_console_suspend
513 [HW] Never suspend the console
514 Disable suspending of consoles during suspend and
515 hibernate operations. Once disabled, debugging
516 messages can reach various consoles while the rest
517 of the system is being put to sleep (ie, while
518 debugging driver suspend/resume hooks). This may
519 not work reliably with all consoles, but is known
520 to work with serial and VGA consoles.
521
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Randy Dunlapa9913042005-10-23 12:57:11 -0700523 Format:
524 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525
Eric W. Biedermandc009d92005-06-25 14:57:52 -0700526 crashkernel=nn[KMG]@ss[KMG]
527 [KNL] Reserve a chunk of physical memory to
528 hold a kernel to switch to with kexec on panic.
529
Bernhard Wallefb391592007-10-18 23:41:02 -0700530 crashkernel=range1:size1[,range2:size2,...][@offset]
531 [KNL] Same as above, but depends on the memory
532 in the running system. The syntax of range is
533 start-[end] where start and end are both
534 a memory unit (amount[KMG]). See also
535 Documentation/kdump/kdump.txt for a example.
536
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 cs4232= [HW,OSS]
538 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
539
540 cs89x0_dma= [HW,NET]
541 Format: <dma>
542
543 cs89x0_media= [HW,NET]
544 Format: { rj45 | aui | bnc }
Randy Dunlapa9913042005-10-23 12:57:11 -0700545
Randy Dunlapa9913042005-10-23 12:57:11 -0700546 dasd= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 See header of drivers/s390/block/dasd_devmap.c.
548
549 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
550 (one device per port)
551 Format: <port#>,<type>
552 See also Documentation/input/joystick-parport.txt
553
554 debug [KNL] Enable kernel debugging (events log level).
555
Ingo Molnarcae2ed92006-07-03 00:24:48 -0700556 debug_locks_verbose=
557 [KNL] verbose self-tests
558 Format=<0|1>
559 Print debugging info while doing the locking API
560 self-tests.
561 We default to 0 (no extra messages), setting it to
562 1 will print _a lot_ more information - normally
563 only useful to kernel developers.
564
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700565 debug_objects [KNL] Enable object debugging
566
Robert P. J. Day2d27a962008-02-03 15:18:45 +0200567 decnet.addr= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 Format: <area>[,<node>]
569 See also Documentation/networking/decnet.txt.
570
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000571 vt.default_blu= [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700572 Format: <blue0>,<blue1>,<blue2>,...,<blue15>
573 Change the default blue palette of the console.
574 This is a 16-member array composed of values
575 ranging from 0-255.
576
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000577 vt.default_grn= [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700578 Format: <green0>,<green1>,<green2>,...,<green15>
579 Change the default green palette of the console.
580 This is a 16-member array composed of values
581 ranging from 0-255.
582
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000583 vt.default_red= [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700584 Format: <red0>,<red1>,<red2>,...,<red15>
585 Change the default red palette of the console.
586 This is a 16-member array composed of values
587 ranging from 0-255.
588
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000589 vt.default_utf8=
590 [VT]
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700591 Format=<0|1>
592 Set system-wide default UTF-8 mode for all tty's.
Samuel Thibaultecb77fa2008-01-03 16:17:54 +0000593 Default is 1, i.e. UTF-8 mode is enabled for all
594 newly opened terminals.
Antonino A. Daplas55ff9782007-05-08 00:38:53 -0700595
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 dhash_entries= [KNL]
597 Set number of hash buckets for dentry cache.
Randy Dunlapa9913042005-10-23 12:57:11 -0700598
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 digi= [HW,SERIAL]
600 IO parameters + enable/disable command.
601
602 digiepca= [HW,SERIAL]
603 See drivers/char/README.epca and
604 Documentation/digiepca.txt.
605
Yinghai Lu093af8d2008-01-30 13:33:32 +0100606 disable_mtrr_trim [X86, Intel and AMD only]
Jesse Barnes99fc8d42008-01-30 13:33:18 +0100607 By default the kernel will trim any uncacheable
608 memory out of your available memory pool based on
609 MTRR settings. This parameter disables that behavior,
610 possibly causing your machine to run very slowly.
611
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 dmasound= [HW,OSS] Sound subsystem buffers
613
614 dscc4.setup= [NET]
615
616 dtc3181e= [HW,SCSI]
617
Robin Getz0ae53642007-10-09 17:24:49 +0800618 earlyprintk= [X86-32,X86-64,SH,BLACKFIN]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 earlyprintk=vga
620 earlyprintk=serial[,ttySn[,baudrate]]
621
Randy Dunlapa9913042005-10-23 12:57:11 -0700622 Append ",keep" to not disable it when the real console
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 takes over.
624
625 Only vga or serial at a time, not both.
626
627 Currently only ttyS0 and ttyS1 are supported.
628
629 Interaction with the standard serial driver is not
630 very good.
631
632 The VGA output is eventually overwritten by the real
633 console.
634
635 eata= [HW,SCSI]
636
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 edd= [EDD]
Tim Gardner8c4dd602008-04-29 01:02:45 -0700638 Format: {"off" | "on" | "skip[mbr]"}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 eisa_irq_edge= [PARISC,HW]
641 See header of drivers/parisc/eisa.c.
642
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700643 elanfreq= [X86-32]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 See comment before function elanfreq_setup() in
645 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
646
647 elevator= [IOSCHED]
Randy Dunlap16ab3ad2006-01-14 13:21:20 -0800648 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
Randy Dunlapa9913042005-10-23 12:57:11 -0700649 See Documentation/block/as-iosched.txt and
650 Documentation/block/deadline-iosched.txt for details.
651
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700652 elfcorehdr= [X86-32, X86_64]
Randy Dunlapa9913042005-10-23 12:57:11 -0700653 Specifies physical address of start of kernel core
Vivek Goyalaac04b32006-01-09 20:51:47 -0800654 image elf header. Generally kexec loader will
655 pass this option to capture kernel.
656 See Documentation/kdump/kdump.txt for details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657
658 enforcing [SELINUX] Set initial enforcing status.
659 Format: {"0" | "1"}
660 See security/selinux/Kconfig help text.
661 0 -- permissive (log only, no denials).
662 1 -- enforcing (deny and log).
663 Default value is 0.
664 Value can be changed at runtime via /selinux/enforce.
665
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 es1371= [HW,OSS]
667 Format: <spdif>,[<nomix>,[<amplifier>]]
668 See also header of sound/oss/es1371.c.
Randy Dunlapa9913042005-10-23 12:57:11 -0700669
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670 ether= [HW,NET] Ethernet cards parameters
671 This option is obsoleted by the "netdev=" option, which
672 has equivalent usage. See its documentation for details.
673
674 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
675 Format: <io>[,<irq>]
676
Akinobu Mitade1ba092006-12-08 02:39:42 -0800677 failslab=
678 fail_page_alloc=
679 fail_make_request=[KNL]
680 General fault injection mechanism.
681 Format: <interval>,<probability>,<space>,<times>
682 See also /Documentation/fault-injection/.
683
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 fd_mcs= [HW,SCSI]
685 See header of drivers/scsi/fd_mcs.c.
686
687 fdomain= [HW,SCSI]
688 See header of drivers/scsi/fdomain.c.
689
690 floppy= [HW]
691 See Documentation/floppy.txt.
692
Alex Chiangf13ae302008-05-08 14:03:23 -0600693 force_pal_cache_flush
694 [IA-64] Avoid check_sal_cache_flush which may hang on
695 buggy SAL_CACHE_FLUSH implementations. Using this
696 parameter will force ia64_sal_cache_flush to call
697 ia64_pal_cache_flush instead of SAL_CACHE_FLUSH.
698
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 gamecon.map[2|3]=
700 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
701 support via parallel port (up to 5 devices per port)
702 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
703 See also Documentation/input/joystick-parport.txt
704
705 gamma= [HW,DRM]
706
Yinghai Luaaf23042008-01-30 13:33:09 +0100707 gart_fix_e820= [X86_64] disable the fix e820 for K8 GART
708 Format: off | on
709 default: on
710
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 gdth= [HW,SCSI]
712 See header of drivers/scsi/gdth.c.
713
714 gpt [EFI] Forces disk with valid GPT signature but
715 invalid Protective MBR to be treated as GPT.
716
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 gvp11= [HW,SCSI]
718
719 hashdist= [KNL,NUMA] Large hashes allocated during boot
720 are distributed across NUMA nodes. Defaults on
721 for IA-64, off otherwise.
Randy Dunlapa9913042005-10-23 12:57:11 -0700722 Format: 0 | 1 (for off | on)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723
724 hcl= [IA-64] SGI's Hardware Graph compatibility layer
725
726 hd= [EIDE] (E)IDE hard drive subsystem geometry
727 Format: <cyl>,<head>,<sect>
728
729 hd?= [HW] (E)IDE subsystem
Randy Dunlap1c10e932008-03-07 21:53:50 +0100730 hd?lun= See Documentation/ide/ide.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731
732 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
733 size of <nn>. This works even on boxes that have no
734 highmem otherwise. This also works to reduce highmem
735 size on bigger boxes.
736
Thomas Gleixner54cdfdb2007-02-16 01:28:11 -0800737 highres= [KNL] Enable/disable high resolution timer mode.
738 Valid parameters: "on", "off"
739 Default: "on"
740
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 hisax= [HW,ISDN]
742 See Documentation/isdn/README.HiSax.
743
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700744 hugepages= [HW,X86-32,IA-64] Maximal number of HugeTLB pages.
Jon Tollefson4ec161c2008-01-04 09:59:50 +1100745 hugepagesz= [HW,IA-64,PPC] The size of the HugeTLB pages.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 i8042.direct [HW] Put keyboard port into non-translated mode
Matt LaPlante84eb8d02006-10-03 22:53:09 +0200748 i8042.dumbkbd [HW] Pretend that controller can only read data from
749 keyboard and cannot control its state
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 (Don't attempt to blink the leds)
751 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
Dmitry Torokhov945ef0d2005-09-04 01:42:00 -0500752 i8042.nokbd [HW] Don't check/create keyboard port
Jiri Kosina75d08c72008-03-13 16:13:59 -0400753 i8042.noloop [HW] Disable the AUX Loopback command while probing
754 for the AUX port
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 i8042.nomux [HW] Don't check presence of an active multiplexing
756 controller
757 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
758 controllers
759 i8042.panicblink=
760 [HW] Frequency with which keyboard LEDs should blink
761 when kernel panics (default is 0.5 sec)
762 i8042.reset [HW] Reset the controller during init and cleanup
763 i8042.unlock [HW] Unlock (ignore) the keylock
764
765 i810= [HW,DRM]
766
Dmitry Torokhove70c9d52005-06-25 14:54:25 -0700767 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
768 indicates that the driver is running on unsupported
769 hardware.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
771 does not match list of supported models.
772 i8k.power_status
773 [HW] Report power status in /proc/i8k
774 (disabled by default)
775 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
776 capability is set.
777
778 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
779 See Documentation/mca.txt.
780
781 icn= [HW,ISDN]
782 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
783
784 ide= [HW] (E)IDE subsystem
Greg Kroah-Hartmana594eeb2008-04-18 00:46:20 +0200785 Format: ide=nodma or ide=doubler
Randy Dunlap1c10e932008-03-07 21:53:50 +0100786 See Documentation/ide/ide.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
Randy Dunlap1c10e932008-03-07 21:53:50 +0100789 See Documentation/ide/ide.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790
Andi Kleenf039b752007-05-02 19:27:12 +0200791 idle= [X86]
792 Format: idle=poll or idle=mwait
793 Poll forces a polling idle loop that can slightly improves the performance
794 of waking up a idle CPU, but will use a lot of power and make the system
795 run hot. Not recommended.
796 idle=mwait. On systems which support MONITOR/MWAIT but the kernel chose
797 to not use it because it doesn't save as much power as a normal idle
798 loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
799 as idle=poll.
Randy Dunlapa9913042005-10-23 12:57:11 -0700800
Denis Cheng594765a2008-02-06 02:57:49 +0100801 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
802 Claim all unknown PCI IDE storage controllers.
803
Ingo Molnar792908222006-12-06 20:40:51 -0800804 ignore_loglevel [KNL]
805 Ignore loglevel setting - this will print /all/
806 kernel messages to the console. Useful for debugging.
807
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 ihash_entries= [KNL]
809 Set number of hash buckets for inode cache.
810
811 in2000= [HW,SCSI]
812 See header of drivers/scsi/in2000.c.
813
814 init= [KNL]
815 Format: <full_path>
816 Run specified binary instead of /sbin/init as init
817 process.
818
819 initcall_debug [KNL] Trace initcalls as they are executed. Useful
820 for working out where the kernel is dying during
821 startup.
822
823 initrd= [BOOT] Specify the location of the initial ramdisk
824
825 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
826 Format: <irq>
827
828 inttest= [IA64]
829
Pavel Machekb552da82008-03-19 15:58:11 +0100830 iommu= [x86]
831 off
832 force
833 noforce
834 biomerge
835 panic
836 nopanic
837 merge
838 nomerge
839 forcesac
840 soft
841
842
Keshavamurthy, Anil Sba395922007-10-21 16:41:49 -0700843 intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option
844 off
845 Disable intel iommu driver.
846 igfx_off [Default Off]
847 By default, gfx is mapped as normal device. If a gfx
848 device has a dedicated DMAR unit, the DMAR unit is
849 bypassed by not enabling DMAR with this option. In
850 this case, gfx device will use physical address for
851 DMA.
Keshavamurthy, Anil S7d3b03c2007-10-21 16:41:53 -0700852 forcedac [x86_64]
853 With this option iommu will not optimize to look
854 for io virtual address below 32 bit forcing dual
855 address cycle on pci bus for cards supporting greater
856 than 32 bit addressing. The default is to look
857 for translation below 32 bit and if not available
858 then look in the higher range.
mark gross5e0d2a62008-03-04 15:22:08 -0800859 strict [Default Off]
860 With this option on every unmap_single operation will
861 result in a hardware IOTLB flush operation as opposed
862 to batching them for performance.
Keshavamurthy, Anil Sba395922007-10-21 16:41:49 -0700863
Rene Hermanb02aae92008-01-30 13:30:05 +0100864 io_delay= [X86-32,X86-64] I/O delay method
Ingo Molnar6e7c4022008-01-30 13:30:05 +0100865 0x80
866 Standard port 0x80 based delay
867 0xed
868 Alternate port 0xed based delay (needed on some systems)
Rene Hermanb02aae92008-01-30 13:30:05 +0100869 udelay
Ingo Molnar6e7c4022008-01-30 13:30:05 +0100870 Simple two microseconds delay
871 none
872 No delay
Rene Hermanb02aae92008-01-30 13:30:05 +0100873
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 io7= [HW] IO7 for Marvel based alpha systems
875 See comment before marvel_specify_io7 in
876 arch/alpha/kernel/core_marvel.c.
877
878 ip= [IP_PNP]
J. Bruce Fields6ded55d2008-04-07 15:59:03 -0400879 See Documentation/filesystems/nfsroot.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880
881 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
Randy Dunlapc8facbb2007-07-31 00:37:40 -0700882 See comment before ip2_setup() in
883 drivers/char/ip2/ip2base.c.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
885 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
886 See header of drivers/scsi/ips.c.
887
Simon Horman72c4a132006-09-13 19:57:18 -0700888 ports= [IP_VS_FTP] IPVS ftp helper module
889 Default is 21.
890 Up to 8 (IP_VS_APP_MAX_PORTS) ports
891 may be specified.
892 Format: <port>,<port>....
893
Alan Cox200803d2005-06-28 20:45:18 -0700894 irqfixup [HW]
895 When an interrupt is not handled search all handlers
896 for it. Intended to get systems with badly broken
897 firmware running.
898
899 irqpoll [HW]
900 When an interrupt is not handled search all handlers
901 for it. Also check all handlers each timer
902 interrupt. Intended to get systems with badly broken
903 firmware running.
904
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 isapnp= [ISAPNP]
Randy Dunlapa9913042005-10-23 12:57:11 -0700906 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907
908 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
Derek Fults22f2e282006-12-06 20:37:11 -0800909 Format:
910 <cpu number>,...,<cpu number>
911 or
912 <cpu number>-<cpu number> (must be a positive range in ascending order)
913 or a mixture
914 <cpu number>,...,<cpu number>-<cpu number>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 This option can be used to specify one or more CPUs
916 to isolate from the general SMP balancing and scheduling
917 algorithms. The only way to move a process onto or off
918 an "isolated" CPU is via the CPU affinity syscalls.
919 <cpu number> begins at 0 and the maximum value is
920 "number of CPUs in system - 1".
921
922 This option is the preferred way to isolate CPUs. The
Randy Dunlapa9913042005-10-23 12:57:11 -0700923 alternative -- manually setting the CPU mask of all
924 tasks in the system -- can cause problems and
925 suboptimal load balancer performance.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926
Randy Dunlapa9913042005-10-23 12:57:11 -0700927 iucv= [HW,NET]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928
929 js= [HW,JOY] Analog joystick
930 See Documentation/input/joystick.txt.
931
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700932 kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
Mel Gormaned7ed362007-07-17 04:03:14 -0700933 specifies the amount of memory usable by the kernel
934 for non-movable allocations. The requested amount is
935 spread evenly throughout all nodes in the system. The
936 remaining memory in each node is used for Movable
937 pages. In the event, a node is too small to have both
938 kernelcore and Movable pages, kernelcore pages will
939 take priority and other nodes will have a larger number
940 of kernelcore pages. The Movable zone is used for the
941 allocation of pages that may be reclaimed or moved
942 by the page migration subsystem. This means that
943 HugeTLB pages may not be allocated from this zone.
944 Note that allocations like PTEs-from-HighMem still
945 use the HighMem zone if it exists, and the Normal
946 zone if it does not.
947
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700948 movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
Mel Gorman7e63efe2007-07-17 04:03:15 -0700949 is similar to kernelcore except it specifies the
950 amount of memory used for migratable allocations.
951 If both kernelcore and movablecore is specified,
952 then kernelcore will be at *least* the specified
953 value but may be more. If movablecore on its own
954 is specified, the administrator must be careful
955 that the amount of memory usable for all allocations
956 is not too small.
957
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958 keepinitrd [HW,ARM]
959
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700960 kstack=N [X86-32,X86-64] Print N words from the kernel stack
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961 in oops dumps.
962
Jason Wessel6cdf6e02008-04-17 20:05:38 +0200963 kgdboc= [HW] kgdb over consoles.
964 Requires a tty driver that supports console polling.
965 (only serial suported for now)
966 Format: <serial_device>[,baud]
967
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 l2cr= [PPC]
969
Robert Brosea78bfbf2008-03-29 07:20:23 +1100970 l3cr= [PPC]
971
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700972 lapic [X86-32,APIC] Enable the local APIC even if BIOS
Randy Dunlapa9913042005-10-23 12:57:11 -0700973 disabled it.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974
Alan Coxcd4f0ef2007-07-31 00:37:59 -0700975 lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer in
Thomas Gleixnere585bef2007-03-23 16:08:01 +0100976 C2 power state.
977
FD Camifcb71f62008-01-06 19:08:56 +0100978 libata.dma= [LIBATA] DMA control
979 libata.dma=0 Disable all PATA and SATA DMA
980 libata.dma=1 PATA and SATA Disk DMA only
981 libata.dma=2 ATAPI (CDROM) DMA only
982 libata.dma=4 Compact Flash DMA only
983 Combinations also work, so libata.dma=3 enables DMA
984 for disks and CDROMs, but not CFs.
985
Dave Jones78e70c22007-09-27 11:50:13 -0400986 libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume
987 when set.
988 Format: <int>
989
Tejun Heo33267322008-02-13 09:15:09 +0900990 libata.force= [LIBATA] Force configurations. The format is comma
991 separated list of "[ID:]VAL" where ID is
992 PORT[:DEVICE]. PORT and DEVICE are decimal numbers
993 matching port, link or device. Basically, it matches
994 the ATA ID string printed on console by libata. If
995 the whole ID part is omitted, the last PORT and DEVICE
996 values are used. If ID hasn't been specified yet, the
997 configuration applies to all ports, links and devices.
998
999 If only DEVICE is omitted, the parameter applies to
1000 the port and all links and devices behind it. DEVICE
1001 number of 0 either selects the first device or the
1002 first fan-out link behind PMP device. It does not
1003 select the host link. DEVICE number of 15 selects the
1004 host link and device attached to it.
1005
1006 The VAL specifies the configuration to force. As long
1007 as there's no ambiguity shortcut notation is allowed.
1008 For example, both 1.5 and 1.5G would work for 1.5Gbps.
1009 The following configurations can be forced.
1010
1011 * Cable type: 40c, 80c, short40c, unk, ign or sata.
1012 Any ID with matching PORT is used.
1013
1014 * SATA link speed limit: 1.5Gbps or 3.0Gbps.
1015
1016 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
1017 udma[/][16,25,33,44,66,100,133] notation is also
1018 allowed.
1019
1020 * [no]ncq: Turn on or off NCQ.
1021
1022 If there are multiple matching configurations changing
1023 the same attribute, the last one is used.
1024
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025 load_ramdisk= [RAM] List of ramdisks to load from floppy
1026 See Documentation/ramdisk.txt.
1027
Randy Dunlapa6b25b62006-01-14 13:21:19 -08001028 lockd.nlm_grace_period=P [NFS] Assign grace period.
1029 Format: <integer>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030
Randy Dunlapa6b25b62006-01-14 13:21:19 -08001031 lockd.nlm_tcpport=N [NFS] Assign TCP port.
1032 Format: <integer>
1033
1034 lockd.nlm_timeout=T [NFS] Assign timeout value.
1035 Format: <integer>
1036
1037 lockd.nlm_udpport=M [NFS] Assign UDP port.
1038 Format: <integer>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039
1040 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
1041 Format: <irq>
1042
1043 loglevel= All Kernel Messages with a loglevel smaller than the
1044 console loglevel will be printed to the console. It can
1045 also be changed with klogd or other programs. The
1046 loglevels are defined as follows:
1047
1048 0 (KERN_EMERG) system is unusable
1049 1 (KERN_ALERT) action must be taken immediately
1050 2 (KERN_CRIT) critical conditions
1051 3 (KERN_ERR) error conditions
1052 4 (KERN_WARNING) warning conditions
1053 5 (KERN_NOTICE) normal but significant condition
1054 6 (KERN_INFO) informational
1055 7 (KERN_DEBUG) debug-level messages
1056
1057 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
Randy Dunlapa9913042005-10-23 12:57:11 -07001058 Format: { n | nk | nM }
1059 n must be a power of two. The default size
1060 is set in the kernel config file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061
Randy Dunlapaccaa242007-10-16 01:29:37 -07001062 logo.nologo [FB] Disables display of the built-in Linux logo.
1063 This may be used to provide more screen space for
1064 kernel log messages and is useful when debugging
1065 kernel boot problems.
1066
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 lp=0 [LP] Specify parallel ports to use, e.g,
1068 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
1069 lp=reset first parallel port). 'lp=0' disables the
1070 lp=auto printer driver. 'lp=reset' (which can be
1071 specified in addition to the ports) causes
1072 attached printers to be reset. Using
1073 lp=port1,port2,... specifies the parallel ports
1074 to associate lp devices with, starting with
1075 lp0. A port specification may be 'none' to skip
1076 that lp device, or a parport name such as
1077 'parport0'. Specifying 'lp=auto' instead of a
1078 port specification list means that device IDs
1079 from each port should be examined, to see if
1080 an IEEE 1284-compliant printer is attached; if
1081 so, the driver will manage that printer.
1082 See also header of drivers/char/lp.c.
1083
1084 lpj=n [KNL]
1085 Sets loops_per_jiffy to given constant, thus avoiding
1086 time-consuming boot-time autodetection (up to 250 ms per
1087 CPU). 0 enables autodetection (default). To determine
1088 the correct value for your kernel, boot with normal
1089 autodetection and see what value is printed. Note that
1090 on SMP systems the preset will be applied to all CPUs,
1091 which is likely to cause problems if your CPUs need
1092 significantly divergent settings. An incorrect value
1093 will cause delays in the kernel to be wrong, leading to
1094 unpredictable I/O errors and other breakage. Although
1095 unlikely, in the extreme case this might damage your
1096 hardware.
1097
1098 ltpc= [NET]
1099 Format: <io>,<irq>,<dma>
1100
Randy Dunlapa9913042005-10-23 12:57:11 -07001101 mac5380= [HW,SCSI] Format:
1102 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103
Randy Dunlapa9913042005-10-23 12:57:11 -07001104 machvec= [IA64] Force the use of a particular machine-vector
1105 (machvec) in a generic kernel.
1106 Example: machvec=hpzx1_swiotlb
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107
Randy Dunlapa9913042005-10-23 12:57:11 -07001108 max_loop= [LOOP] Maximum number of loopback devices that can
Linus Torvalds1da177e2005-04-16 15:20:36 -07001109 be mounted
1110 Format: <1-256>
1111
1112 maxcpus= [SMP] Maximum number of processors that an SMP kernel
Len Brown61ec7562007-08-16 03:34:22 -04001113 should make use of. maxcpus=n : n >= 0 limits the
1114 kernel to using 'n' processors. n=0 is a special case,
1115 it is equivalent to "nosmp", which also disables
1116 the IO APIC.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117
Bob Picco2b2c3752005-06-29 18:00:00 -07001118 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
1119 equal to this physical address is ignored.
1120
Randy Dunlapa9913042005-10-23 12:57:11 -07001121 max_luns= [SCSI] Maximum number of LUNs to probe.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122 Should be between 1 and 2^32-1.
1123
1124 max_report_luns=
Randy Dunlapa9913042005-10-23 12:57:11 -07001125 [SCSI] Maximum number of LUNs received.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 Should be between 1 and 16384.
1127
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128 mcatest= [IA-64]
1129
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001130 mce [X86-32] Machine Check Exception
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131
Andi Kleen909dd322007-10-17 18:04:38 +02001132 mce=option [X86-64] See Documentation/x86_64/boot-options.txt
1133
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 md= [HW] RAID subsystems devices and level
1135 See Documentation/md.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -07001136
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 mdacon= [MDA]
1138 Format: <first>,<last>
1139 Specifies range of consoles to be captured by the MDA.
Randy Dunlapa9913042005-10-23 12:57:11 -07001140
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
1142 Amount of memory to be used when the kernel is not able
1143 to see the whole system memory or for test.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001144 [X86-32] Use together with memmap= to avoid physical
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145 address space collisions. Without memmap= PCI devices
1146 could be placed at addresses belonging to unused RAM.
1147
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001148 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
Linus Torvalds1da177e2005-04-16 15:20:36 -07001149 memory.
1150
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001151 memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 E820 memory map, as specified by the user.
1153 Such memmap=exactmap lines can be constructed based on
1154 BIOS output or other requirements. See the memmap=nn@ss
1155 option description.
1156
1157 memmap=nn[KMG]@ss[KMG]
1158 [KNL] Force usage of a specific region of memory
1159 Region of memory to be used, from ss to ss+nn.
1160
1161 memmap=nn[KMG]#ss[KMG]
1162 [KNL,ACPI] Mark specific memory as ACPI data.
1163 Region of memory to be used, from ss to ss+nn.
1164
1165 memmap=nn[KMG]$ss[KMG]
1166 [KNL,ACPI] Mark specific memory as reserved.
1167 Region of memory to be used, from ss to ss+nn.
Pavel Machek13128482008-03-24 12:29:43 -07001168 Example: Exclude memory from 0x18690000-0x1869ffff
1169 memmap=64K$0x18690000
1170 or
1171 memmap=0x10000$0x18690000
Linus Torvalds1da177e2005-04-16 15:20:36 -07001172
Yinghai Luc64df702008-03-21 18:56:19 -07001173 memtest= [KNL,X86_64] Enable memtest
1174 Format: <integer>
1175 range: 0,4 : pattern number
1176 default : 0 <disable>
1177
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178 meye.*= [HW] Set MotionEye Camera parameters
1179 See Documentation/video4linux/meye.txt.
1180
Andres Salomon8f368812007-10-12 23:04:06 +02001181 mfgpt_irq= [IA-32] Specify the IRQ to use for the
1182 Multi-Function General Purpose Timers on AMD Geode
1183 platforms.
1184
Willy Tarreaue6c4dc62008-01-30 13:33:33 +01001185 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
1186 the BIOS has incorrectly applied a workaround. TinyBIOS
1187 version 0.98 is known to be affected, 0.99 fixes the
1188 problem by letting the user disable the workaround.
1189
Linus Torvalds1da177e2005-04-16 15:20:36 -07001190 mga= [HW,DRM]
1191
1192 mousedev.tap_time=
1193 [MOUSE] Maximum time between finger touching and
1194 leaving touchpad surface for touch to be considered
1195 a tap and be reported as a left button click (for
1196 touchpads working in absolute mode only).
1197 Format: <msecs>
1198 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
1199 reporting absolute coordinates, such as tablets
1200 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
1201 reporting absolute coordinates, such as tablets
1202
1203 mpu401= [HW,OSS]
1204 Format: <io>,<irq>
1205
1206 MTD_Partition= [MTD]
1207 Format: <name>,<region-number>,<size>,<offset>
1208
Randy Dunlapa9913042005-10-23 12:57:11 -07001209 MTD_Region= [MTD] Format:
1210 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001211
1212 mtdparts= [MTD]
Randy Dunlapc8facbb2007-07-31 00:37:40 -07001213 See drivers/mtd/cmdlinepart.c.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214
1215 mtouchusb.raw_coordinates=
Randy Dunlapa9913042005-10-23 12:57:11 -07001216 [HW] Make the MicroTouch USB driver use raw coordinates
1217 ('y', default) or cooked coordinates ('n')
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218
1219 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
1220
1221 NCR_D700= [HW,SCSI]
1222 See header of drivers/scsi/NCR_D700.c.
1223
1224 ncr5380= [HW,SCSI]
1225
1226 ncr53c400= [HW,SCSI]
1227
1228 ncr53c400a= [HW,SCSI]
1229
1230 ncr53c406a= [HW,SCSI]
1231
1232 ncr53c8xx= [HW,SCSI]
1233
1234 netdev= [NET] Network devices parameters
1235 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
1236 Note that mem_start is often overloaded to mean
1237 something different and driver-specific.
Randy Dunlapa9913042005-10-23 12:57:11 -07001238 This usage is only documented in each driver source
1239 file if at all.
1240
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 nfsaddrs= [NFS]
J. Bruce Fields6ded55d2008-04-07 15:59:03 -04001242 See Documentation/filesystems/nfsroot.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243
1244 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
J. Bruce Fields6ded55d2008-04-07 15:59:03 -04001245 See Documentation/filesystems/nfsroot.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001246
Trond Myklebusta72b4422006-01-03 09:55:41 +01001247 nfs.callback_tcpport=
1248 [NFS] set the TCP port on which the NFSv4 callback
1249 channel should listen.
1250
Trond Myklebust58df0952006-01-03 09:55:57 +01001251 nfs.idmap_cache_timeout=
1252 [NFS] set the maximum lifetime for idmapper cache
1253 entries.
1254
Trond Myklebustf43bf0b2007-10-09 12:01:04 -04001255 nfs.enable_ino64=
1256 [NFS] enable 64-bit inode numbers.
1257 If zero, the NFS client will fake up a 32-bit inode
1258 number for the readdir() and stat() syscalls instead
1259 of returning the full 64-bit number.
1260 The default is to return 64-bit inode numbers.
1261
Haavard Skinnemoene7ba1762007-10-10 14:58:29 +02001262 nmi_debug= [KNL,AVR32] Specify one or more actions to take
1263 when a NMI is triggered.
1264 Format: [state][,regs][,debounce][,die]
1265
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001266 nmi_watchdog= [KNL,BUGS=X86-32] Debugging features for SMP kernels
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001268 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
Linus Torvalds1da177e2005-04-16 15:20:36 -07001269 emulation library even if a 387 maths coprocessor
1270 is present.
1271
Christoph Lameterc1aee212007-05-31 00:40:47 -07001272 noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
1273 caches in the slab allocator. Saves per-node memory,
1274 but will impact performance.
Paul Menage3395ee02006-12-06 20:32:16 -08001275
Randy Dunlapa9913042005-10-23 12:57:11 -07001276 noalign [KNL,ARM]
1277
Linus Torvalds1da177e2005-04-16 15:20:36 -07001278 noapic [SMP,APIC] Tells the kernel to not make use of any
1279 IOAPICs that may be present in the system.
1280
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281 nobats [PPC] Do not use BATs for mapping kernel lowmem
1282 on "Classic" PPC cores.
1283
1284 nocache [ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001285
Shailabh Nagar163ecdf2006-07-30 03:03:11 -07001286 nodelayacct [KNL] Disable per-task delay accounting
1287
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1289
Huang, Ying8b2cb7a2008-01-30 13:32:11 +01001290 noefi [X86-32,X86-64] Disable EFI runtime services support.
1291
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292 noexec [IA-64]
1293
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001294 noexec [X86-32,X86-64]
Jiri Slabyf5a1b192008-04-12 10:28:25 +02001295 On X86-32 available only on PAE configured kernels.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 noexec=on: enable non-executable mappings (default)
Jiri Slabyf5a1b192008-04-12 10:28:25 +02001297 noexec=off: disable non-executable mappings
1298
1299 noexec32 [X86-64]
1300 This affects only 32-bit executables.
1301 noexec32=on: enable non-executable mappings (default)
1302 read doesn't imply executable mappings
1303 noexec32=off: disable non-executable mappings
1304 read implies executable mappings
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001306 nofxsr [BUGS=X86-32] Disables x86 floating point extended
Chuck Ebbert4f886512006-03-23 02:59:34 -08001307 register save and restore. The kernel will only save
1308 legacy floating-point registers on task switch.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001309
Andi Kleen191679f2008-01-30 13:33:21 +01001310 noclflush [BUGS=X86] Don't use the CLFLUSH instruction
1311
Linus Torvalds1da177e2005-04-16 15:20:36 -07001312 nohlt [BUGS=ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001313
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001314 no-hlt [BUGS=X86-32] Tells the kernel that the hlt
Linus Torvalds1da177e2005-04-16 15:20:36 -07001315 instruction doesn't work correctly and not to
1316 use it.
1317
1318 nohalt [IA-64] Tells the kernel not to use the power saving
1319 function PAL_HALT_LIGHT when idle. This increases
1320 power-consumption. On the positive side, it reduces
1321 interrupt wake-up latency, which may improve performance
1322 in certain environments such as networked servers or
1323 real-time systems.
1324
Thomas Gleixner79bf2bb2007-02-16 01:28:03 -08001325 nohz= [KNL] Boottime enable/disable dynamic ticks
1326 Valid arguments: on, off
1327 Default: on
1328
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001329 noirqbalance [X86-32,SMP,KNL] Disable kernel irq balancing
Zachary Amsden8542b202006-12-07 02:14:09 +01001330
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001331 noirqdebug [X86-32] Disables the code which attempts to detect and
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332 disable unhandled interrupt sources.
1333
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001334 no_timer_check [X86-32,X86_64,APIC] Disables the code which tests for
Zachary Amsden8542b202006-12-07 02:14:09 +01001335 broken timer IRQ sources.
1336
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337 noisapnp [ISAPNP] Disables ISA PnP code.
1338
1339 noinitrd [RAM] Tells the kernel not to load any configured
1340 initial RAM disk.
1341
1342 nointroute [IA-64]
1343
Tony Luck0aa366f2007-07-20 11:22:30 -07001344 nojitter [IA64] Disables jitter checking for ITC timers.
1345
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001346 nolapic [X86-32,APIC] Do not enable or use the local APIC.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001348 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
Thomas Gleixnerad62ca22007-03-22 00:11:21 -08001349
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350 noltlbs [PPC] Do not use large page/tlb entries for kernel
1351 lowmem mapping on PPC40x.
1352
Horms312f1f02006-02-22 09:57:55 +09001353 nomca [IA-64] Disable machine check abort handling
1354
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001355 nomce [X86-32] Machine Check Exception
Hormsabe37e52006-04-01 01:36:09 +02001356
Andres Salomon83d73842007-10-12 23:04:06 +02001357 nomfgpt [X86-32] Disable Multi-Function General Purpose
1358 Timer usage (for AMD Geode machines).
1359
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001360 noreplace-paravirt [X86-32,PV_OPS] Don't patch paravirt_ops
Jeremy Fitzhardinge959b4fd2007-05-02 19:27:16 +02001361
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001362 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
Jeremy Fitzhardingeb7fb4af2007-05-02 19:27:13 +02001363 with UP alternatives
1364
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365 noresidual [PPC] Don't use residual data on PReP machines.
1366
Randy Dunlapa9913042005-10-23 12:57:11 -07001367 noresume [SWSUSP] Disables resume and restores original swap
1368 space.
1369
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370 no-scroll [VGA] Disables scrollback.
1371 This is required for the Braillex ib80-piezo Braille
1372 reader made by F.H. Papenmeier (Germany).
1373
1374 nosbagart [IA-64]
1375
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001376 nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support.
Chuck Ebbert4f886512006-03-23 02:59:34 -08001377
Len Brown61ec7562007-08-16 03:34:22 -04001378 nosmp [SMP] Tells an SMP kernel to act as a UP kernel,
1379 and disable the IO APIC. legacy for "maxcpus=0".
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380
Dave Jones97842212007-07-15 23:41:05 -07001381 nosoftlockup [KNL] Disable the soft-lockup detector.
1382
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383 nosync [HW,M68K] Disables sync negotiation for all devices.
1384
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001385 notsc [BUGS=X86-32] Disable Time Stamp Counter
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386
1387 nousb [USB] Disable the USB subsystem
1388
1389 nowb [ARM]
Randy Dunlapa9913042005-10-23 12:57:11 -07001390
Fenghua Yua6c75b862008-03-14 13:57:08 -07001391 nptcg= [IA64] Override max number of concurrent global TLB
1392 purges which is reported from either PAL_VM_SUMMARY or
1393 SAL PALO.
1394
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07001395 numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
1396 one of ['zone', 'node', 'default'] can be specified
1397 This can be set from sysctl after boot.
1398 See Documentation/sysctl/vm.txt for details.
1399
Dave Jonesa61c2d72006-01-07 23:18:19 +00001400 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1401
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07001402 olpc_ec_timeout= [OLPC] ms delay when issuing EC commands
1403 Rather than timing out after 20 ms if an EC
1404 command is not properly ACKed, override the length
1405 of the timeout. We have interrupts disabled while
1406 waiting for the ACK, so if this is set too high
1407 interrupts *may* be lost!
1408
Linus Torvalds1da177e2005-04-16 15:20:36 -07001409 opl3= [HW,OSS]
1410 Format: <io>
1411
Linus Torvalds1da177e2005-04-16 15:20:36 -07001412 oprofile.timer= [HW]
1413 Use timer interrupt instead of performance counters
1414
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415 osst= [HW,SCSI] SCSI Tape Driver
1416 Format: <buffer_size>,<write_threshold>
1417 See also Documentation/scsi/st.txt.
1418
1419 panic= [KNL] Kernel behaviour on panic
1420 Format: <timeout>
1421
1422 parkbd.port= [HW] Parallel port number the keyboard adapter is
1423 connected to, default is 0.
1424 Format: <parport#>
1425 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1426 0 for XT, 1 for AT (default is AT).
Randy Dunlapa9913042005-10-23 12:57:11 -07001427 Format: <mode>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001428
Randy Dunlapa9913042005-10-23 12:57:11 -07001429 parport= [HW,PPT] Specify parallel ports. 0 disables.
1430 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1431 Use 'auto' to force the driver to use any
1432 IRQ/DMA settings detected (the default is to
1433 ignore detected IRQ/DMA settings because of
1434 possible conflicts). You can specify the base
1435 address, IRQ, and DMA settings; IRQ and DMA
1436 should be numbers, or 'auto' (for using detected
1437 settings on that particular port), or 'nofifo'
1438 (to avoid using a FIFO even if it is detected).
1439 Parallel ports are assigned in the order they
1440 are specified on the command line, starting
1441 with parport0.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001442
Randy Dunlapa9913042005-10-23 12:57:11 -07001443 parport_init_mode= [HW,PPT]
1444 Configure VIA parallel port to operate in
1445 a specific mode. This is necessary on Pegasos
1446 computer where firmware has no options for setting
1447 up parallel port mode and sets it to spp.
1448 Currently this function knows 686a and 8231 chips.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001449 Format: [spp|ps2|epp|ecp|ecpepp]
1450
Randy Dunlapa9913042005-10-23 12:57:11 -07001451 pas2= [HW,OSS] Format:
1452 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1453
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 pas16= [HW,SCSI]
1455 See header of drivers/scsi/pas16.c.
1456
Andrew Mortondd287792006-03-23 03:00:57 -08001457 pause_on_oops=
1458 Halt all CPUs after the first oops has been printed for
1459 the specified number of seconds. This is to be used if
1460 your oopses keep scrolling off the screen.
1461
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462 pcbit= [HW,ISDN]
1463
1464 pcd. [PARIDE]
1465 See header of drivers/block/paride/pcd.c.
1466 See also Documentation/paride.txt.
1467
Randy Dunlapa9913042005-10-23 12:57:11 -07001468 pci=option[,option...] [PCI] various PCI subsystem options:
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001469 off [X86-32] don't probe for the PCI bus
1470 bios [X86-32] force use of PCI BIOS, don't access
Randy Dunlapa9913042005-10-23 12:57:11 -07001471 the hardware directly. Use this if your machine
1472 has a non-standard PCI host bridge.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001473 nobios [X86-32] disallow use of PCI BIOS, only direct
Randy Dunlapa9913042005-10-23 12:57:11 -07001474 hardware access methods are allowed. Use this
1475 if you experience crashes upon bootup and you
1476 suspect they are caused by the BIOS.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001477 conf1 [X86-32] Force use of PCI Configuration
Randy Dunlapa9913042005-10-23 12:57:11 -07001478 Mechanism 1.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001479 conf2 [X86-32] Force use of PCI Configuration
Randy Dunlapa9913042005-10-23 12:57:11 -07001480 Mechanism 2.
Randy Dunlap7f785762007-10-05 13:17:58 -07001481 noaer [PCIE] If the PCIEAER kernel config parameter is
1482 enabled, this kernel boot option can be used to
1483 disable the use of PCIE advanced error reporting.
Jeff Garzik32a2eea2007-10-11 16:57:27 -04001484 nodomains [PCI] Disable support for multiple PCI
1485 root domains (aka PCI segments, in ACPI-speak).
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001486 nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI
Bjorn Helgaas61be6d62006-02-15 15:17:43 -08001487 Configuration
Matthew Wilcox309e57d2006-03-05 22:33:34 -07001488 nomsi [MSI] If the PCI_MSI kernel config parameter is
1489 enabled, this kernel boot option can be used to
1490 disable the use of MSI interrupts system-wide.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001491 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
Randy Dunlapa9913042005-10-23 12:57:11 -07001492 routing table. These calls are known to be buggy
1493 on several machines and they hang the machine
1494 when used, but on other computers it's the only
1495 way to get the interrupt routing table. Try
1496 this option if the kernel is unable to allocate
1497 IRQs or discover secondary PCI buses on your
1498 motherboard.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001499 rom [X86-32] Assign address space to expansion ROMs.
Randy Dunlapa9913042005-10-23 12:57:11 -07001500 Use with caution as certain devices share
1501 address decoders between ROMs and other
1502 resources.
Gary Hadebb71ad82008-05-12 13:57:46 -07001503 norom [X86-32,X86_64] Do not assign address space to
1504 expansion ROMs that do not already have
1505 BIOS assigned address ranges.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001506 irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be
Randy Dunlapa9913042005-10-23 12:57:11 -07001507 assigned automatically to PCI devices. You can
1508 make the kernel exclude IRQs of your ISA cards
1509 this way.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001510 pirqaddr=0xAAAAA [X86-32] Specify the physical address
Randy Dunlapa9913042005-10-23 12:57:11 -07001511 of the PIRQ table (normally generated
1512 by the BIOS) if it is outside the
1513 F0000h-100000h range.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001514 lastbus=N [X86-32] Scan all buses thru bus #N. Can be
Randy Dunlapa9913042005-10-23 12:57:11 -07001515 useful if the kernel is unable to find your
1516 secondary buses and you want to tell it
1517 explicitly which ones they are.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001518 assign-busses [X86-32] Always assign all PCI bus
Randy Dunlapa9913042005-10-23 12:57:11 -07001519 numbers ourselves, overriding
1520 whatever the firmware may have done.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001521 usepirqmask [X86-32] Honor the possible IRQ mask stored
Randy Dunlapa9913042005-10-23 12:57:11 -07001522 in the BIOS $PIR table. This is needed on
1523 some systems with broken BIOSes, notably
1524 some HP Pavilion N5400 and Omnibook XE3
1525 notebooks. This will have no effect if ACPI
1526 IRQ routing is enabled.
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001527 noacpi [X86-32] Do not use ACPI for IRQ routing
Randy Dunlapa9913042005-10-23 12:57:11 -07001528 or for PCI scanning.
Gary Hade62f420f2007-10-03 15:56:51 -07001529 use_crs [X86-32] Use _CRS for PCI resource
1530 allocation.
Randy Dunlapa9913042005-10-23 12:57:11 -07001531 routeirq Do IRQ routing for all PCI devices.
1532 This is normally done in pci_enable_device(),
1533 so this option is a temporary workaround
1534 for broken drivers that don't call it.
Yinghai Lu13a6ddb2008-03-27 01:31:18 -07001535 skip_isa_align [X86] do not align io start addr, so can
1536 handle more pci cards
Randy Dunlapa9913042005-10-23 12:57:11 -07001537 firmware [ARM] Do not re-enumerate the bus but instead
1538 just use the configuration from the
1539 bootloader. This is currently used on
1540 IXP2000 systems where the bus has to be
1541 configured a certain way for adjunct CPUs.
Andi Kleen0637a702006-09-26 10:52:41 +02001542 noearly [X86] Don't do any early type 1 scanning.
1543 This might help on some broken boards which
1544 machine check when some devices' config space
1545 is read. But various workarounds are disabled
1546 and some IOMMU drivers will not work.
Matt Domsch6b4b78f2006-09-29 15:23:23 -05001547 bfsort Sort PCI devices into breadth-first order.
1548 This sorting is done to get a device
1549 order compatible with older (<= 2.4) kernels.
1550 nobfsort Don't sort PCI devices into breadth-first order.
Atsushi Nemoto4516a612007-02-05 16:36:06 -08001551 cbiosize=nn[KMG] The fixed amount of bus space which is
1552 reserved for the CardBus bridge's IO window.
1553 The default value is 256 bytes.
1554 cbmemsize=nn[KMG] The fixed amount of bus space which is
1555 reserved for the CardBus bridge's memory
1556 window. The default value is 64 megabytes.
Matt Domsch6b4b78f2006-09-29 15:23:23 -05001557
Linus Torvalds1da177e2005-04-16 15:20:36 -07001558 pcmv= [HW,PCMCIA] BadgePAD 4
1559
1560 pd. [PARIDE]
1561 See Documentation/paride.txt.
1562
1563 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1564 boot time.
1565 Format: { 0 | 1 }
1566 See arch/parisc/kernel/pdc_chassis.c
1567
1568 pf. [PARIDE]
1569 See Documentation/paride.txt.
1570
1571 pg. [PARIDE]
1572 See Documentation/paride.txt.
1573
1574 pirq= [SMP,APIC] Manual mp-table setup
1575 See Documentation/i386/IO-APIC.txt.
1576
1577 plip= [PPT,NET] Parallel port network link
1578 Format: { parport<nr> | timid | 0 }
1579 See also Documentation/parport.txt.
1580
1581 pnpacpi= [ACPI]
1582 { off }
1583
1584 pnpbios= [ISAPNP]
1585 { on | off | curr | res | no-curr | no-res }
1586
1587 pnp_reserve_irq=
1588 [ISAPNP] Exclude IRQs for the autoconfiguration
1589
1590 pnp_reserve_dma=
1591 [ISAPNP] Exclude DMAs for the autoconfiguration
1592
1593 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
Randy Dunlapa9913042005-10-23 12:57:11 -07001594 Ranges are in pairs (I/O port base and size).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001595
1596 pnp_reserve_mem=
Randy Dunlapa9913042005-10-23 12:57:11 -07001597 [ISAPNP] Exclude memory regions for the
1598 autoconfiguration.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599 Ranges are in pairs (memory base and size).
1600
Ingo Molnar45807a12007-07-15 23:40:10 -07001601 print-fatal-signals=
1602 [KNL] debug: print fatal signals
1603 print-fatal-signals=1: print segfault info to
1604 the kernel console.
1605 default: off.
1606
Randy Dunlape84845c2007-07-15 23:40:25 -07001607 printk.time= Show timing data prefixed to each printk message line
1608 Format: <bool> (1/Y/y=enable, 0/N/n=disable)
1609
Linus Torvalds1da177e2005-04-16 15:20:36 -07001610 profile= [KNL] Enable kernel profiling via /proc/profile
Randy Dunlapa9913042005-10-23 12:57:11 -07001611 Format: [schedule,]<number>
1612 Param: "schedule" - profile schedule points.
1613 Param: <number> - step/bucket size as a power of 2 for
1614 statistical time based profiling.
Mel Gormanb3da2a72007-10-24 18:23:50 +02001615 Param: "sleep" - profile D-state sleeping (millisecs).
1616 Requires CONFIG_SCHEDSTATS
Dave Jonesc0fe2e62007-10-20 03:08:22 +02001617 Param: "kvm" - profile VM exits.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001618
Randy Dunlapa9913042005-10-23 12:57:11 -07001619 processor.max_cstate= [HW,ACPI]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 Limit processor to maximum C-state
1621 max_cstate=9 overrides any DMI blacklist limit.
1622
Len Brown41c0d862005-12-28 12:43:51 -05001623 processor.nocst [HW,ACPI]
1624 Ignore the _CST method to determine C-states,
1625 instead using the legacy FADT method
1626
Linus Torvalds1da177e2005-04-16 15:20:36 -07001627 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1628 before loading.
1629 See Documentation/ramdisk.txt.
1630
Randy Dunlapa9913042005-10-23 12:57:11 -07001631 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1632 probe for; one of (bare|imps|exps|lifebook|any).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1634 per second.
Randy Dunlapa9913042005-10-23 12:57:11 -07001635 psmouse.resetafter= [HW,MOUSE]
1636 Try to reset the device after so many bad packets
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637 (0 = never).
1638 psmouse.resolution=
1639 [HW,MOUSE] Set desired mouse resolution, in dpi.
1640 psmouse.smartscroll=
Randy Dunlapa9913042005-10-23 12:57:11 -07001641 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642 0 = disabled, 1 = enabled (default).
1643
1644 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
Randy Dunlapa9913042005-10-23 12:57:11 -07001645 Format:
1646 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647
1648 pt. [PARIDE]
1649 See Documentation/paride.txt.
1650
Kay Sieversdc8c8582007-08-15 12:25:38 +02001651 pty.legacy_count=
1652 [KNL] Number of legacy pty's. Overwrites compiled-in
1653 default number.
1654
Randy Dunlap7d2c5022006-09-29 02:01:02 -07001655 quiet [KNL] Disable most log messages
Randy Dunlapa9913042005-10-23 12:57:11 -07001656
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 r128= [HW,DRM]
1658
1659 raid= [HW,RAID]
1660 See Documentation/md.txt.
1661
Randy Dunlapa9913042005-10-23 12:57:11 -07001662 ramdisk_blocksize= [RAM]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001663 See Documentation/ramdisk.txt.
Randy Dunlapa9913042005-10-23 12:57:11 -07001664
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 See Documentation/ramdisk.txt.
1667
Robert P. J. Day24aaef82008-02-03 15:20:26 +02001668 rcupdate.blimit= [KNL,BOOT]
1669 Set maximum number of finished RCU callbacks to process
1670 in one batch.
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001671
Robert P. J. Day24aaef82008-02-03 15:20:26 +02001672 rcupdate.qhimark= [KNL,BOOT]
1673 Set threshold of queued
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001674 RCU callbacks over which batch limiting is disabled.
1675
Robert P. J. Day24aaef82008-02-03 15:20:26 +02001676 rcupdate.qlowmark= [KNL,BOOT]
1677 Set threshold of queued RCU callbacks below which
1678 batch limiting is re-enabled.
Dipankar Sarma21a1ea92006-03-07 21:55:33 -08001679
Olof Johanssonffdfc402005-09-06 15:17:19 -07001680 rdinit= [KNL]
1681 Format: <full_path>
1682 Run specified binary instead of /init from the ramdisk,
1683 used for early userspace startup. See initrd.
1684
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001685 reboot= [BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
Linus Torvalds1da177e2005-04-16 15:20:36 -07001686 Format: <reboot_mode>[,<reboot_mode2>[,...]]
Mauro Carvalho Chehabe53dd082007-09-15 07:38:47 -03001687 See arch/*/kernel/reboot.c or arch/*/kernel/process.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688
1689 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1690
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001691 reservetop= [X86-32]
Zachary Amsden461a9af2006-09-25 23:32:25 -07001692 Format: nn[KMG]
1693 Reserves a hole at the top of the kernel virtual
1694 address space.
1695
Vivek Goyal7e962872006-09-27 01:50:44 -07001696 reset_devices [KNL] Force drivers to reset the underlying device
1697 during initialization.
1698
Randy Dunlapa9913042005-10-23 12:57:11 -07001699 resume= [SWSUSP]
1700 Specify the partition device for software suspend
Linus Torvalds1da177e2005-04-16 15:20:36 -07001701
Rafael J. Wysockiecbd0da2006-12-06 20:34:13 -08001702 resume_offset= [SWSUSP]
1703 Specify the offset from the beginning of the partition
1704 given by "resume=" at which the swap header is located,
1705 in <PAGE_SIZE> units (needed only for swap files).
1706 See Documentation/power/swsusp-and-swap-files.txt
1707
Michael Neuling0a7b35cb2007-02-10 01:44:33 -08001708 retain_initrd [RAM] Keep initrd memory after extraction
1709
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710 rhash_entries= [KNL,NET]
1711 Set number of hash buckets for route cache
1712
1713 riscom8= [HW,SERIAL]
1714 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1715
1716 ro [KNL] Mount root device read-only on boot
1717
1718 root= [KNL] Root filesystem
1719
1720 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1721 mount the root filesystem
1722
1723 rootflags= [KNL] Set root filesystem mount option string
1724
1725 rootfstype= [KNL] Set root filesystem type
1726
Pierre Ossmancc1ed752007-07-15 23:40:35 -07001727 rootwait [KNL] Wait (indefinitely) for root device to show up.
1728 Useful for devices that are detected asynchronously
1729 (e.g. USB and MMC devices).
1730
James Morris20510f22007-10-16 23:31:32 -07001731 root_plug.vendor_id=
1732 [ROOTPLUG] Override the default vendor ID
1733
1734 root_plug.product_id=
1735 [ROOTPLUG] Override the default product ID
1736
1737 root_plug.debug=
1738 [ROOTPLUG] Enable debugging output
1739
Linus Torvalds1da177e2005-04-16 15:20:36 -07001740 rw [KNL] Mount root device read-write on boot
1741
1742 S [KNL] Run init in single mode
1743
1744 sa1100ir [NET]
1745 See drivers/net/irda/sa1100_ir.c.
1746
Linus Torvalds1da177e2005-04-16 15:20:36 -07001747 sbni= [NET] Granch SBNI12 leased line adapter
Randy Dunlapa9913042005-10-23 12:57:11 -07001748
Linus Torvalds1da177e2005-04-16 15:20:36 -07001749 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1750 Format: <io>[,<timeout>[,<isapnp>]]
1751
1752 scsi_debug_*= [SCSI]
1753 See drivers/scsi/scsi_debug.c.
1754
1755 scsi_default_dev_flags=
1756 [SCSI] SCSI default device flags
1757 Format: <integer>
1758
1759 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1760 Format: <vendor>:<model>:<flags>
1761 (flags are integer value)
1762
Randy Dunlap6af66322007-11-14 16:52:25 -08001763 scsi_logging_level= [SCSI] a bit mask of logging levels
1764 See drivers/scsi/scsi_logging.h for bits. Also
1765 settable via sysctl at dev.scsi.logging_level
1766 (/proc/sys/dev/scsi/logging_level).
1767 There is also a nice 'scsi_logging_level' script in the
1768 S390-tools package, available for download at
1769 http://www-128.ibm.com/developerworks/linux/linux390/s390-tools-1.5.4.html
Linus Torvalds1da177e2005-04-16 15:20:36 -07001770
Matthew Wilcox3e082a92006-09-28 15:19:20 -06001771 scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are
1772 discovered. async scans them in kernel threads,
1773 allowing boot to proceed. none ignores them, expecting
1774 user space to do the scan.
1775
Linus Torvalds1da177e2005-04-16 15:20:36 -07001776 selinux [SELINUX] Disable or enable SELinux at boot time.
1777 Format: { "0" | "1" }
1778 See security/selinux/Kconfig help text.
1779 0 -- disable.
1780 1 -- enable.
1781 Default value is set via kernel config option.
1782 If enabled at boot time, /selinux/disable can be used
1783 later to disable prior to initial policy load.
1784
James Morris4e5ab4c2006-06-09 00:33:33 -07001785 selinux_compat_net =
1786 [SELINUX] Set initial selinux_compat_net flag value.
Mauro Carvalho Chehabe53dd082007-09-15 07:38:47 -03001787 Format: { "0" | "1" }
1788 0 -- use new secmark-based packet controls
1789 1 -- use legacy packet controls
1790 Default value is 0 (preferred).
1791 Value can be changed at runtime via
1792 /selinux/compat_net.
James Morris4e5ab4c2006-06-09 00:33:33 -07001793
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001794 serialnumber [BUGS=X86-32]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001795
Linus Torvalds1da177e2005-04-16 15:20:36 -07001796 shapers= [NET]
1797 Maximal number of shapers.
Randy Dunlapa9913042005-10-23 12:57:11 -07001798
Linus Torvalds1da177e2005-04-16 15:20:36 -07001799 sim710= [SCSI,HW]
1800 See header of drivers/scsi/sim710.c.
1801
1802 simeth= [IA-64]
1803 simscsi=
Randy Dunlapa9913042005-10-23 12:57:11 -07001804
Linus Torvalds1da177e2005-04-16 15:20:36 -07001805 slram= [HW,MTD]
1806
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001807 slub_debug[=options[,slabs]] [MM, SLUB]
1808 Enabling slub_debug allows one to determine the
1809 culprit if slab objects become corrupted. Enabling
1810 slub_debug can create guard zones around objects and
1811 may poison objects when not in use. Also tracks the
1812 last alloc / free. For more information see
1813 Documentation/vm/slub.txt.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001814
1815 slub_max_order= [MM, SLUB]
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001816 Determines the maximum allowed order for slabs.
1817 A high setting may cause OOMs due to memory
1818 fragmentation. For more information see
1819 Documentation/vm/slub.txt.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001820
1821 slub_min_objects= [MM, SLUB]
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001822 The minimum number of objects per slab. SLUB will
1823 increase the slab order up to slub_max_order to
1824 generate a sufficiently large slab able to contain
1825 the number of objects indicated. The higher the number
1826 of objects the smaller the overhead of tracking slabs
1827 and the less frequently locks need to be acquired.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001828 For more information see Documentation/vm/slub.txt.
1829
1830 slub_min_order= [MM, SLUB]
1831 Determines the mininum page order for slabs. Must be
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001832 lower than slub_max_order.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001833 For more information see Documentation/vm/slub.txt.
1834
1835 slub_nomerge [MM, SLUB]
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001836 Disable merging of slabs with similar size. May be
Christoph Lameterc1aee212007-05-31 00:40:47 -07001837 necessary if there is some reason to distinguish
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001838 allocs to different slabs. Debug options disable
1839 merging on their own.
Christoph Lameterc1aee212007-05-31 00:40:47 -07001840 For more information see Documentation/vm/slub.txt.
1841
Linus Torvalds1da177e2005-04-16 15:20:36 -07001842 smart2= [HW]
1843 Format: <io1>[,<io2>[,...,<io8>]]
1844
Alan Coxcd4f0ef2007-07-31 00:37:59 -07001845 smp-alt-once [X86-32,SMP] On a hotplug CPU system, only
Jeremy Fitzhardingeb7fb4af2007-05-02 19:27:13 +02001846 attempt to substitute SMP alternatives once at boot.
1847
Bjorn Helgaasd0d4f692007-05-08 00:36:05 -07001848 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
1849 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
1850 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
1851 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
1852 smsc-ircc2.ircc_irq= [HW] IRQ line
1853 smsc-ircc2.ircc_dma= [HW] DMA channel
1854 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
1855 0: Toshiba Satellite 1800 (GP data pin select)
1856 1: Fast pin select (default)
1857 2: ATC IRMode
1858
Linus Torvalds1da177e2005-04-16 15:20:36 -07001859 snd-ad1816a= [HW,ALSA]
1860
1861 snd-ad1848= [HW,ALSA]
1862
1863 snd-ali5451= [HW,ALSA]
1864
1865 snd-als100= [HW,ALSA]
1866
1867 snd-als4000= [HW,ALSA]
1868
1869 snd-azt2320= [HW,ALSA]
1870
1871 snd-cmi8330= [HW,ALSA]
1872
1873 snd-cmipci= [HW,ALSA]
1874
1875 snd-cs4231= [HW,ALSA]
1876
1877 snd-cs4232= [HW,ALSA]
1878
1879 snd-cs4236= [HW,ALSA]
1880
1881 snd-cs4281= [HW,ALSA]
1882
1883 snd-cs46xx= [HW,ALSA]
1884
1885 snd-dt019x= [HW,ALSA]
1886
1887 snd-dummy= [HW,ALSA]
1888
1889 snd-emu10k1= [HW,ALSA]
1890
1891 snd-ens1370= [HW,ALSA]
1892
1893 snd-ens1371= [HW,ALSA]
1894
1895 snd-es968= [HW,ALSA]
1896
1897 snd-es1688= [HW,ALSA]
1898
1899 snd-es18xx= [HW,ALSA]
1900
1901 snd-es1938= [HW,ALSA]
1902
1903 snd-es1968= [HW,ALSA]
1904
1905 snd-fm801= [HW,ALSA]
1906
1907 snd-gusclassic= [HW,ALSA]
1908
1909 snd-gusextreme= [HW,ALSA]
1910
1911 snd-gusmax= [HW,ALSA]
1912
1913 snd-hdsp= [HW,ALSA]
1914
1915 snd-ice1712= [HW,ALSA]
1916
1917 snd-intel8x0= [HW,ALSA]
1918
1919 snd-interwave= [HW,ALSA]
1920
1921 snd-interwave-stb=
1922 [HW,ALSA]
1923
1924 snd-korg1212= [HW,ALSA]
1925
1926 snd-maestro3= [HW,ALSA]
1927
1928 snd-mpu401= [HW,ALSA]
1929
1930 snd-mtpav= [HW,ALSA]
1931
1932 snd-nm256= [HW,ALSA]
1933
1934 snd-opl3sa2= [HW,ALSA]
1935
1936 snd-opti92x-ad1848=
1937 [HW,ALSA]
1938
1939 snd-opti92x-cs4231=
1940 [HW,ALSA]
1941
1942 snd-opti93x= [HW,ALSA]
1943
1944 snd-pmac= [HW,ALSA]
1945
1946 snd-rme32= [HW,ALSA]
1947
1948 snd-rme96= [HW,ALSA]
1949
1950 snd-rme9652= [HW,ALSA]
1951
1952 snd-sb8= [HW,ALSA]
1953
1954 snd-sb16= [HW,ALSA]
1955
1956 snd-sbawe= [HW,ALSA]
1957
1958 snd-serial= [HW,ALSA]
1959
1960 snd-sgalaxy= [HW,ALSA]
1961
1962 snd-sonicvibes= [HW,ALSA]
1963
1964 snd-sun-amd7930=
1965 [HW,ALSA]
1966
1967 snd-sun-cs4231= [HW,ALSA]
1968
1969 snd-trident= [HW,ALSA]
1970
1971 snd-usb-audio= [HW,ALSA,USB]
1972
1973 snd-via82xx= [HW,ALSA]
1974
1975 snd-virmidi= [HW,ALSA]
1976
1977 snd-wavefront= [HW,ALSA]
1978
1979 snd-ymfpci= [HW,ALSA]
Randy Dunlapa9913042005-10-23 12:57:11 -07001980
Linus Torvalds1da177e2005-04-16 15:20:36 -07001981 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1982 See Documentation/sonypi.txt
1983
1984 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1985 See Documentation/specialix.txt.
1986
1987 spia_io_base= [HW,MTD]
1988 spia_fio_base=
1989 spia_pedr=
1990 spia_peddr=
1991
1992 sscape= [HW,OSS]
1993 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
Randy Dunlapa9913042005-10-23 12:57:11 -07001994
Linus Torvalds1da177e2005-04-16 15:20:36 -07001995 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1996 See Documentation/scsi/st.txt.
1997
Linus Torvalds1da177e2005-04-16 15:20:36 -07001998 sti= [PARISC,HW]
1999 Format: <num>
2000 Set the STI (builtin display/keyboard on the HP-PARISC
2001 machines) console (graphic card) which should be used
2002 as the initial boot-console.
2003 See also comment in drivers/video/console/sticore.c.
2004
2005 sti_font= [HW]
2006 See comment in drivers/video/console/sticore.c.
2007
2008 stifb= [HW]
2009 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
2010
Greg Banks42a7fc42007-03-06 01:42:23 -08002011 sunrpc.pool_mode=
2012 [NFS]
2013 Control how the NFS server code allocates CPUs to
2014 service thread pools. Depending on how many NICs
2015 you have and where their interrupts are bound, this
2016 option will affect which CPUs will do NFS serving.
2017 Note: this parameter cannot be changed while the
2018 NFS server is running.
2019
2020 auto the server chooses an appropriate mode
2021 automatically using heuristics
2022 global a single global pool contains all CPUs
2023 percpu one pool for each CPU
2024 pernode one pool for each NUMA node (equivalent
2025 to global on non-NUMA machines)
2026
Linus Torvalds1da177e2005-04-16 15:20:36 -07002027 swiotlb= [IA-64] Number of I/O TLB slabs
Randy Dunlapa9913042005-10-23 12:57:11 -07002028
Linus Torvalds1da177e2005-04-16 15:20:36 -07002029 switches= [HW,M68k]
2030
2031 sym53c416= [HW,SCSI]
2032 See header of drivers/scsi/sym53c416.c.
2033
Ingo Molnar5d6f6472006-12-13 00:34:36 -08002034 sysrq_always_enabled
2035 [KNL]
2036 Ignore sysrq setting - this boot parameter will
2037 neutralize any effect of /proc/sys/kernel/sysrq.
2038 Useful for debugging.
2039
Linus Torvalds1da177e2005-04-16 15:20:36 -07002040 t128= [HW,SCSI]
2041 See header of drivers/scsi/t128.c.
2042
2043 tdfx= [HW,DRM]
2044
2045 thash_entries= [KNL,NET]
2046 Set number of hash buckets for TCP connection
2047
Len Brownf8707ec2007-08-12 00:12:54 -04002048 thermal.act= [HW,ACPI]
2049 -1: disable all active trip points in all thermal zones
2050 <degrees C>: override all lowest active trip points
2051
Len Brownc52a7412007-08-14 15:49:32 -04002052 thermal.crt= [HW,ACPI]
2053 -1: disable all critical trip points in all thermal zones
2054 <degrees C>: lower all critical trip points
2055
Len Brownf5487142007-08-12 00:12:44 -04002056 thermal.nocrt= [HW,ACPI]
2057 Set to disable actions on ACPI thermal zone
2058 critical and hot trip points.
2059
Len Brown72b33ef2007-08-12 00:12:17 -04002060 thermal.off= [HW,ACPI]
2061 1: disable ACPI thermal control
2062
Len Browna70cdc52007-08-12 00:12:35 -04002063 thermal.psv= [HW,ACPI]
2064 -1: disable all passive trip points
2065 <degrees C>: override all passive trip points to this value
2066
Len Brown730ff342007-08-12 00:12:26 -04002067 thermal.tzp= [HW,ACPI]
2068 Specify global default ACPI thermal zone polling rate
2069 <deci-seconds>: poll all this frequency
2070 0: no polling (default)
2071
Linus Torvalds1da177e2005-04-16 15:20:36 -07002072 tipar.timeout= [HW,PPT]
2073 Set communications timeout in tenths of a second
2074 (default 15).
2075
2076 tipar.delay= [HW,PPT]
2077 Set inter-bit delay in microseconds (default 10).
2078
Linus Torvalds1da177e2005-04-16 15:20:36 -07002079 tmscsim= [HW,SCSI]
2080 See comment before function dc390_setup() in
2081 drivers/scsi/tmscsim.c.
2082
2083 tp720= [HW,PS2]
2084
2085 trix= [HW,OSS] MediaTrix AudioTrix Pro
Randy Dunlapa9913042005-10-23 12:57:11 -07002086 Format:
2087 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
2088
Randy Dunlapa9913042005-10-23 12:57:11 -07002089 turbografx.map[2|3]= [HW,JOY]
2090 TurboGraFX parallel port interface
2091 Format:
2092 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
Linus Torvalds1da177e2005-04-16 15:20:36 -07002093 See also Documentation/input/joystick-parport.txt
2094
2095 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
2096 See header of drivers/scsi/u14-34f.c.
2097
2098 uart401= [HW,OSS]
2099 Format: <io>,<irq>
2100
2101 uart6850= [HW,OSS]
2102 Format: <io>,<irq>
2103
Alan Stern5f8364b2006-12-05 16:29:55 -05002104 uhci-hcd.ignore_oc=
2105 [USB] Ignore overcurrent events (default N).
2106 Some badly-designed motherboards generate lots of
2107 bogus events, for ports that aren't wired to
2108 anything. Set this parameter to avoid log spamming.
2109 Note that genuine overcurrent events won't be
2110 reported either.
2111
Alan Sternb5e795f2007-02-20 15:00:53 -05002112 usbcore.autosuspend=
2113 [USB] The autosuspend time delay (in seconds) used
2114 for newly-detected USB devices (default 2). This
2115 is the time required before an idle device will be
2116 autosuspended. Devices for which the delay is set
Alan Sterneaafbc32007-03-13 16:39:15 -04002117 to a negative value won't be autosuspended at all.
Alan Sternb5e795f2007-02-20 15:00:53 -05002118
Linus Torvalds1da177e2005-04-16 15:20:36 -07002119 usbhid.mousepoll=
2120 [USBHID] The interval which mice are to be polled at.
Randy Dunlapa9913042005-10-23 12:57:11 -07002121
Alan Coxcd4f0ef2007-07-31 00:37:59 -07002122 vdso= [X86-32,SH,x86-64]
Jeremy Fitzhardinge1dbf527c2007-05-02 19:27:12 +02002123 vdso=2: enable compat VDSO (default with COMPAT_VDSO)
Ingo Molnare6e54942006-06-27 02:53:50 -07002124 vdso=1: enable VDSO (default)
2125 vdso=0: disable VDSO mapping
2126
Roland McGrathaf65d642008-01-30 13:30:43 +01002127 vdso32= [X86-32,X86-64]
2128 vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
2129 vdso32=1: enable 32-bit VDSO (default)
2130 vdso32=0: disable 32-bit VDSO mapping
2131
Yasuaki Ishimatsud080d392007-07-17 21:22:55 +09002132 vector= [IA-64,SMP]
2133 vector=percpu: enable percpu vector domain
2134
Linus Torvalds1da177e2005-04-16 15:20:36 -07002135 video= [FB] Frame buffer configuration
2136 See Documentation/fb/modedb.txt.
2137
Alan Coxcd4f0ef2007-07-31 00:37:59 -07002138 vga= [BOOT,X86-32] Select a particular video mode
Randy Dunlapa9913042005-10-23 12:57:11 -07002139 See Documentation/i386/boot.txt and
2140 Documentation/svga.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002141 Use vga=ask for menu.
2142 This is actually a boot loader parameter; the value is
2143 passed to the kernel using a special protocol.
2144
Randy Dunlapa9913042005-10-23 12:57:11 -07002145 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146 size of <nn>. This can be used to increase the
2147 minimum size (128MB on x86). It can also be used to
2148 decrease the size and leave more room for directly
2149 mapped kernel RAM.
2150
Peter Oberparleiter585c3042006-06-29 15:08:25 +02002151 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
2152 Format: <command>
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153
Peter Oberparleiter585c3042006-06-29 15:08:25 +02002154 vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
2155 Format: <command>
2156
2157 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
2158 Format: <command>
Randy Dunlapa9913042005-10-23 12:57:11 -07002159
Linus Torvalds1da177e2005-04-16 15:20:36 -07002160 waveartist= [HW,OSS]
2161 Format: <io>,<irq>,<dma>,<dma2>
Randy Dunlapa9913042005-10-23 12:57:11 -07002162
Linus Torvalds1da177e2005-04-16 15:20:36 -07002163 wd33c93= [HW,SCSI]
2164 See header of drivers/scsi/wd33c93.c.
2165
2166 wd7000= [HW,SCSI]
2167 See header of drivers/scsi/wd7000.c.
2168
2169 wdt= [WDT] Watchdog
Gabriel C8dfe9c22007-08-10 13:01:00 -07002170 See Documentation/watchdog/wdt.txt.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002171
2172 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
2173 xd_geo= See header of drivers/block/xd.c.
2174
2175 xirc2ps_cs= [NET,PCMCIA]
Randy Dunlapa9913042005-10-23 12:57:11 -07002176 Format:
2177 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
Linus Torvalds1da177e2005-04-16 15:20:36 -07002178
Andi Kleena62eaf12006-02-16 23:41:58 +01002179 norandmaps Don't use address space randomization
2180 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
2181
Randy Dunlapa9913042005-10-23 12:57:11 -07002182______________________________________________________________________
Linus Torvalds1da177e2005-04-16 15:20:36 -07002183
2184TODO:
2185
2186 Add documentation for ALSA options.
2187 Add more DRM drivers.