4 The following is a consolidated list of the kernel parameters as implemented
5 (mostly) by the __setup() macro and sorted into English Dictionary order
6 (defined as ignoring all punctuation and sorting digits before letters in a
7 case insensitive manner), and with descriptions where known.
9 Module parameters for loadable modules are specified only as the
10 parameter name with optional '=' and value as appropriate, such as:
12 modprobe usbcore blinkenlights=1
14 Module parameters for modules that are built into the kernel image
15 are specified on the kernel command line with the module name plus
16 '.' plus parameter name, with '=' and value if appropriate, such as:
18 usbcore.blinkenlights=1
20 This document may not be entirely up to date and comprehensive. The command
21 "modinfo -p ${modulename}" shows a current list of all parameters of a loadable
22 module. Loadable modules, after being loaded into the running kernel, also
23 reveal their parameters in /sys/module/${modulename}/parameters/. Some of these
24 parameters may be changed at runtime by the command
25 "echo -n ${value} > /sys/module/${modulename}/parameters/${parm}".
27 The parameters listed below are only valid if certain kernel build options were
28 enabled and if respective hardware is present. The text in square brackets at
29 the beginning of each description states the restrictions within which a
30 parameter is applicable:
32 ACPI ACPI support is enabled.
33 ALSA ALSA sound support is enabled.
34 APIC APIC support is enabled.
35 APM Advanced Power Management support is enabled.
36 AX25 Appropriate AX.25 support is enabled.
37 CD Appropriate CD support is enabled.
38 DRM Direct Rendering Management support is enabled.
39 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
40 EFI EFI Partitioning (GPT) is enabled
41 EIDE EIDE/ATAPI support is enabled.
42 FB The frame buffer device is enabled.
43 HW Appropriate hardware is enabled.
44 IA-32 IA-32 aka i386 architecture is enabled.
45 IA-64 IA-64 architecture is enabled.
46 IOSCHED More than one I/O scheduler is enabled.
47 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
48 ISAPNP ISA PnP code is enabled.
49 ISDN Appropriate ISDN support is enabled.
50 JOY Appropriate joystick support is enabled.
51 LP Printer support is enabled.
52 LOOP Loopback device support is enabled.
53 M68k M68k architecture is enabled.
54 These options have more detailed description inside of
55 Documentation/m68k/kernel-options.txt.
56 MCA MCA bus support is enabled.
57 MDA MDA console support is enabled.
58 MOUSE Appropriate mouse support is enabled.
59 MSI Message Signaled Interrupts (PCI).
60 MTD MTD support is enabled.
61 NET Appropriate network support is enabled.
62 NUMA NUMA support is enabled.
63 GENERIC_TIME The generic timeofday code is enabled.
64 NFS Appropriate NFS support is enabled.
65 OSS OSS sound support is enabled.
66 PARIDE The ParIDE subsystem is enabled.
67 PARISC The PA-RISC architecture is enabled.
68 PCI PCI bus support is enabled.
69 PCMCIA The PCMCIA subsystem is enabled.
70 PNP Plug & Play support is enabled.
71 PPC PowerPC architecture is enabled.
72 PPT Parallel port support is enabled.
73 PS2 Appropriate PS/2 support is enabled.
74 RAM RAM disk support is enabled.
75 S390 S390 architecture is enabled.
76 SCSI Appropriate SCSI support is enabled.
77 A lot of drivers has their options described inside of
79 SELINUX SELinux support is enabled.
80 SERIAL Serial support is enabled.
81 SMP The kernel is an SMP kernel.
82 SPARC Sparc architecture is enabled.
83 SWSUSP Software suspend is enabled.
84 TS Appropriate touchscreen support is enabled.
85 USB USB support is enabled.
86 USBHID USB Human Interface Device support is enabled.
87 V4L Video For Linux support is enabled.
88 VGA The VGA console has been enabled.
89 VT Virtual terminal support is enabled.
90 WDT Watchdog support is enabled.
91 XT IBM PC/XT MFM hard disk support is enabled.
92 X86-64 X86-64 architecture is enabled.
93 More X86-64 boot options can be found in
94 Documentation/x86_64/boot-options.txt .
96 In addition, the following text indicates that the option:
98 BUGS= Relates to possible processor bugs on the said processor.
99 KNL Is a kernel start-up parameter.
100 BOOT Is a boot loader parameter.
102 Parameters denoted with BOOT are actually interpreted by the boot
103 loader, and have no meaning to the kernel directly.
104 Do not modify the syntax of boot loader parameters without extreme
105 need or coordination with <Documentation/i386/boot.txt>.
107 Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
108 a trailing = on the name of any parameter states that that parameter will
109 be entered as an environment variable, whereas its absence indicates that
110 it will appear as a kernel argument readable via /proc/cmdline by programs
111 running once the system is up.
113 53c7xx= [HW,SCSI] Amiga SCSI controllers
114 See header of drivers/scsi/53c7xx.c.
115 See also Documentation/scsi/ncr53c7xx.txt.
117 acpi= [HW,ACPI] Advanced Configuration and Power Interface
118 Format: { force | off | ht | strict | noirq }
119 force -- enable ACPI if default was off
120 off -- disable ACPI if default was on
121 noirq -- do not use ACPI for IRQ routing
122 ht -- run only enough ACPI to enable Hyper Threading
123 strict -- Be less tolerant of platforms that are not
124 strictly ACPI specification compliant.
126 See also Documentation/pm.txt, pci=noacpi
128 acpi_sleep= [HW,ACPI] Sleep options
129 Format: { s3_bios, s3_mode }
130 See Documentation/power/video.txt
132 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
133 Format: { level | edge | high | low }
135 acpi_irq_balance [HW,ACPI]
136 ACPI will balance active IRQs
139 acpi_irq_nobalance [HW,ACPI]
140 ACPI will not move active IRQs (default)
143 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
145 Format: <irq>,<irq>...
147 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
148 Format: <irq>,<irq>...
150 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
151 Format: To spoof as Windows 98: ="Microsoft Windows"
153 acpi_osi= [HW,ACPI] empty param disables _OSI
155 acpi_serialize [HW,ACPI] force serialization of AML methods
157 acpi_skip_timer_override [HW,ACPI]
158 Recognize and ignore IRQ0/pin2 Interrupt Override.
159 For broken nForce2 BIOS resulting in XT-PIC timer.
161 acpi_dbg_layer= [HW,ACPI]
163 Each bit of the <int> indicates an ACPI debug layer,
164 1: enable, 0: disable. It is useful for boot time
165 debugging. After system has booted up, it can be set
166 via /proc/acpi/debug_layer.
168 acpi_dbg_level= [HW,ACPI]
170 Each bit of the <int> indicates an ACPI debug level,
171 1: enable, 0: disable. It is useful for boot time
172 debugging. After system has booted up, it can be set
173 via /proc/acpi/debug_level.
175 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
177 acpi_generic_hotkey [HW,ACPI]
178 Allow consolidated generic hotkey driver to
179 override platform specific driver.
180 See also Documentation/acpi-hotkey.txt.
182 acpi_pm_good [IA-32,X86-64]
183 Override the pmtimer bug detection: force the kernel
184 to assume that this machine's pmtimer latches its value
185 and always returns good values.
187 enable_timer_pin_1 [i386,x86-64]
188 Enable PIN 1 of APIC timer
189 Can be useful to work around chipset bugs
190 (in particular on some ATI chipsets).
191 The kernel tries to set a reasonable default.
193 disable_timer_pin_1 [i386,x86-64]
194 Disable PIN 1 of APIC timer
195 Can be useful to work around chipset bugs.
198 Format: <io>,<irq>,<dma>,<dma2>
199 See also Documentation/sound/oss/AD1816.
202 Format: <io>,<irq>,<dma>,<dma2>,<type>
208 See header of drivers/scsi/advansys.c.
210 advwdt= [HW,WDT] Advantech WDT
211 Format: <iostart>,<iostop>
213 aedsp16= [HW,OSS] Audio Excel DSP 16
214 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
215 See also header of sound/oss/aedsp16.c.
218 See Documentation/scsi/aha152x.txt.
221 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
224 See Documentation/scsi/aic7xxx.txt.
227 See Documentation/scsi/aic79xx.txt.
229 amijoy.map= [HW,JOY] Amiga joystick support
230 Map of devices attached to JOY0DAT and JOY1DAT
232 See also Documentation/kernel/input/joystick.txt
234 analog.map= [HW,JOY] Analog joystick and gamepad support
235 Specifies type or capabilities of an analog joystick
236 connected to one of 16 gameports
237 Format: <type1>,<type2>,..<type16>
240 Power management functions (SPARCstation-4/5 + deriv.)
242 Disable APC CPU standby support. SPARCstation-Fox does
243 not play well with APC CPU idle - disable it if you have
244 APC and your system crashes randomly.
246 apic= [APIC,i386] Change the output verbosity whilst booting
247 Format: { quiet (default) | verbose | debug }
248 Change the amount of debugging information output
249 when initialising the APIC and IO-APIC components.
251 apm= [APM] Advanced Power Management
252 See header of arch/i386/kernel/apm.c.
257 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
258 Format: <io>,<irq>,<nodeID>
262 atarimouse= [HW,MOUSE] Atari Mouse
264 atascsi= [HW,SCSI] Atari SCSI
266 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
267 EzKey and similar keyboards
269 atkbd.reset= [HW] Reset keyboard during initialization
271 atkbd.set= [HW] Select keyboard code set
272 Format: <int> (2 = AT (default), 3 = PS/2)
274 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
277 atkbd.softraw= [HW] Choose between synthetic and real raw mode
278 Format: <bool> (0 = real, 1 = synthetic (default))
280 atkbd.softrepeat= [HW]
281 Use software keyboard repeat
285 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
286 Format: <io>,<memsize>,<isapnp>
288 aztcd= [HW,CD] Aztech CD268 CDROM driver
289 Format: <io>,0x79 (?)
291 baycom_epp= [HW,AX25]
294 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
296 See header of drivers/net/hamradio/baycom_par.c.
298 baycom_ser_fdx= [HW,AX25]
299 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
300 Format: <io>,<irq>,<mode>[,<baud>]
301 See header of drivers/net/hamradio/baycom_ser_fdx.c.
303 baycom_ser_hdx= [HW,AX25]
304 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
305 Format: <io>,<irq>,<mode>
306 See header of drivers/net/hamradio/baycom_ser_hdx.c.
308 blkmtd_device= [HW,MTD]
314 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
315 bttv.radio= Most important insmod options are available as
317 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
318 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
321 See drivers/scsi/BusLogic.c, comment before function
322 BusLogic_ParseDriverOptions().
324 c101= [NET] Moxa C101 synchronous serial card
326 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
327 Sometimes CPU hardware bugs make them report the cache
328 size incorrectly. The kernel will attempt work arounds
329 to fix known problems, but for some CPUs it is not
330 possible to determine what the correct size should be.
331 This option provides an override for these situations.
334 Format: <io>,<irq>[,PAS]
335 See header of drivers/cdrom/cdu31a.c.
337 chandev= [HW,NET] Generic channel device initialisation
339 checkreqprot [SELINUX] Set initial checkreqprot flag value.
340 Format: { "0" | "1" }
341 See security/selinux/Kconfig help text.
342 0 -- check protection applied by kernel (includes
343 any implied execute protection).
344 1 -- check protection requested by application.
345 Default value is set via a kernel config option.
346 Value can be changed at runtime via
347 /selinux/checkreqprot.
349 clock= [BUGS=IA-32, HW] gettimeofday clocksource override.
351 Forces specified clocksource (if avaliable) to be used
352 when calculating gettimeofday(). If specified
353 clocksource is not avalible, it defaults to PIT.
354 Format: { pit | tsc | cyclone | pmtmr }
358 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
359 over the 8254 in addition to over the IO-APIC. The
360 kernel tries to set a sensible default.
362 hpet= [IA-32,HPET] option to disable HPET and use PIT.
366 Format: { auto | [<io>,][<irq>] }
368 com20020= [HW,NET] ARCnet - COM20020 chipset
370 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
372 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
376 ARCnet - COM90xx chipset (memory-mapped buffers)
377 Format: <io>[,<irq>[,<memstart>]]
379 condev= [HW,S390] console device
382 console= [KNL] Output console device and options.
384 tty<n> Use the virtual console device <n>.
388 Use the specified serial port. The options are of
389 the form "bbbbpnf", where "bbbb" is the baud rate,
390 "p" is parity ("n", "o", or "e"), "n" is number of
391 bits, and "f" is flow control ("r" for RTS or
392 omit it). Default is "9600n8".
394 See Documentation/serial-console.txt for more
396 Documentation/networking/netconsole.txt for an
399 uart,io,<addr>[,options]
400 uart,mmio,<addr>[,options]
401 Start an early, polled-mode console on the 8250/16550
402 UART at the specified I/O port or MMIO address,
403 switching to the matching ttyS device later. The
404 options are the same as for ttyS, above.
406 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
408 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
411 Format: { parport<nr> | auto | none }
413 crashkernel=nn[KMG]@ss[KMG]
414 [KNL] Reserve a chunk of physical memory to
415 hold a kernel to switch to with kexec on panic.
418 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
423 cs89x0_media= [HW,NET]
424 Format: { rj45 | aui | bnc }
426 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
429 See header of drivers/s390/block/dasd_devmap.c.
431 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
432 (one device per port)
433 Format: <port#>,<type>
434 See also Documentation/input/joystick-parport.txt
436 debug [KNL] Enable kernel debugging (events log level).
439 [KNL] verbose self-tests
441 Print debugging info while doing the locking API
443 We default to 0 (no extra messages), setting it to
444 1 will print _a lot_ more information - normally
445 only useful to kernel developers.
448 Format: <area>[,<node>]
449 See also Documentation/networking/decnet.txt.
452 Set number of hash buckets for dentry cache.
455 IO parameters + enable/disable command.
457 digiepca= [HW,SERIAL]
458 See drivers/char/README.epca and
459 Documentation/digiepca.txt.
461 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
463 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
465 dmasound= [HW,OSS] Sound subsystem buffers
471 earlyprintk= [IA-32,X86-64]
473 earlyprintk=serial[,ttySn[,baudrate]]
475 Append ",keep" to not disable it when the real console
478 Only vga or serial at a time, not both.
480 Currently only ttyS0 and ttyS1 are supported.
482 Interaction with the standard serial driver is not
485 The VGA output is eventually overwritten by the real
490 ec_intr= [HW,ACPI] ACPI Embedded Controller interrupt mode
493 non-0: interrupt mode (default)
500 Format: {"of[f]" | "sk[ipmbr]"}
501 See comment in arch/i386/boot/edd.S
504 Format: <id>,<membase>,<irq>
506 eisa_irq_edge= [PARISC,HW]
507 See header of drivers/parisc/eisa.c.
510 See comment before function elanfreq_setup() in
511 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
514 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
515 See Documentation/block/as-iosched.txt and
516 Documentation/block/deadline-iosched.txt for details.
518 elfcorehdr= [IA-32, X86_64]
519 Specifies physical address of start of kernel core
520 image elf header. Generally kexec loader will
521 pass this option to capture kernel.
522 See Documentation/kdump/kdump.txt for details.
524 enforcing [SELINUX] Set initial enforcing status.
526 See security/selinux/Kconfig help text.
527 0 -- permissive (log only, no denials).
528 1 -- enforcing (deny and log).
530 Value can be changed at runtime via /selinux/enforce.
533 Format: <lineout>[,<micbias>]
534 See also header of sound/oss/es1370.c.
537 Format: <spdif>,[<nomix>,[<amplifier>]]
538 See also header of sound/oss/es1371.c.
540 ether= [HW,NET] Ethernet cards parameters
541 This option is obsoleted by the "netdev=" option, which
542 has equivalent usage. See its documentation for details.
544 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
548 See header of drivers/scsi/fd_mcs.c.
551 See header of drivers/scsi/fdomain.c.
554 See Documentation/floppy.txt.
556 ftape= [HW] Floppy Tape subsystem debugging options.
557 See Documentation/ftape.txt.
560 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
561 support via parallel port (up to 5 devices per port)
562 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
563 See also Documentation/input/joystick-parport.txt
568 See header of drivers/scsi/gdth.c.
570 gpt [EFI] Forces disk with valid GPT signature but
571 invalid Protective MBR to be treated as GPT.
577 Format: <io>,<irq>,<dma>,<dma16>
581 hashdist= [KNL,NUMA] Large hashes allocated during boot
582 are distributed across NUMA nodes. Defaults on
583 for IA-64, off otherwise.
584 Format: 0 | 1 (for off | on)
586 hcl= [IA-64] SGI's Hardware Graph compatibility layer
588 hd= [EIDE] (E)IDE hard drive subsystem geometry
589 Format: <cyl>,<head>,<sect>
591 hd?= [HW] (E)IDE subsystem
592 hd?lun= See Documentation/ide.txt.
594 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
595 size of <nn>. This works even on boxes that have no
596 highmem otherwise. This also works to reduce highmem
597 size on bigger boxes.
600 See Documentation/isdn/README.HiSax.
602 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
604 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
606 i8042.direct [HW] Put keyboard port into non-translated mode
607 i8042.dumbkbd [HW] Pretend that controlled can only read data from
608 keyboard and can not control its state
609 (Don't attempt to blink the leds)
610 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
611 i8042.nokbd [HW] Don't check/create keyboard port
612 i8042.nomux [HW] Don't check presence of an active multiplexing
614 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
617 [HW] Frequency with which keyboard LEDs should blink
618 when kernel panics (default is 0.5 sec)
619 i8042.reset [HW] Reset the controller during init and cleanup
620 i8042.unlock [HW] Unlock (ignore) the keylock
624 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
625 indicates that the driver is running on unsupported
627 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
628 does not match list of supported models.
630 [HW] Report power status in /proc/i8k
631 (disabled by default)
632 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
635 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
636 See Documentation/mca.txt.
639 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
641 ide= [HW] (E)IDE subsystem
642 Format: ide=nodma or ide=doubler or ide=reverse
643 See Documentation/ide.txt.
645 ide?= [HW] (E)IDE subsystem
646 Format: ide?=noprobe or chipset specific parameters.
647 See Documentation/ide.txt.
649 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
650 See Documentation/ide.txt.
653 Format: idle=poll or idle=halt
656 Set number of hash buckets for inode cache.
659 See header of drivers/scsi/in2000.c.
663 Run specified binary instead of /sbin/init as init
666 initcall_debug [KNL] Trace initcalls as they are executed. Useful
667 for working out where the kernel is dying during
670 initrd= [BOOT] Specify the location of the initial ramdisk
672 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
675 combined_mode= [HW] control which driver uses IDE ports in combined
676 mode: legacy IDE driver, libata, or both
677 (in the libata case, libata.atapi_enabled=1 may be
678 useful as well). Note that using the ide or libata
679 options may affect your device naming (e.g. by
680 changing hdc to sdb).
681 Format: combined (default), ide, or libata
685 io7= [HW] IO7 for Marvel based alpha systems
686 See comment before marvel_specify_io7 in
687 arch/alpha/kernel/core_marvel.c.
690 See Documentation/nfsroot.txt.
692 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
693 See comment before ip2_setup() in drivers/char/ip2.c.
695 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
696 See header of drivers/scsi/ips.c.
698 ports= [IP_VS_FTP] IPVS ftp helper module
700 Up to 8 (IP_VS_APP_MAX_PORTS) ports
702 Format: <port>,<port>....
705 When an interrupt is not handled search all handlers
706 for it. Intended to get systems with badly broken
710 When an interrupt is not handled search all handlers
711 for it. Also check all handlers each timer
712 interrupt. Intended to get systems with badly broken
716 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
718 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
719 Format: <cpu number>,...,<cpu number>
720 This option can be used to specify one or more CPUs
721 to isolate from the general SMP balancing and scheduling
722 algorithms. The only way to move a process onto or off
723 an "isolated" CPU is via the CPU affinity syscalls.
724 <cpu number> begins at 0 and the maximum value is
725 "number of CPUs in system - 1".
727 This option is the preferred way to isolate CPUs. The
728 alternative -- manually setting the CPU mask of all
729 tasks in the system -- can cause problems and
730 suboptimal load balancer performance.
733 Format: <io>,<irq>,<dma>,<setup>
737 js= [HW,JOY] Analog joystick
738 See Documentation/input/joystick.txt.
742 kstack=N [IA-32,X86-64] Print N words from the kernel stack
747 lapic [IA-32,APIC] Enable the local APIC even if BIOS
750 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
751 Format: addr:<io>,irq:<irq>
753 llsc*= [IA64] See function print_params() in
754 arch/ia64/sn/kernel/llsc4.c.
756 load_ramdisk= [RAM] List of ramdisks to load from floppy
757 See Documentation/ramdisk.txt.
759 lockd.nlm_grace_period=P [NFS] Assign grace period.
762 lockd.nlm_tcpport=N [NFS] Assign TCP port.
765 lockd.nlm_timeout=T [NFS] Assign timeout value.
768 lockd.nlm_udpport=M [NFS] Assign UDP port.
771 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
774 loglevel= All Kernel Messages with a loglevel smaller than the
775 console loglevel will be printed to the console. It can
776 also be changed with klogd or other programs. The
777 loglevels are defined as follows:
779 0 (KERN_EMERG) system is unusable
780 1 (KERN_ALERT) action must be taken immediately
781 2 (KERN_CRIT) critical conditions
782 3 (KERN_ERR) error conditions
783 4 (KERN_WARNING) warning conditions
784 5 (KERN_NOTICE) normal but significant condition
785 6 (KERN_INFO) informational
786 7 (KERN_DEBUG) debug-level messages
788 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
789 Format: { n | nk | nM }
790 n must be a power of two. The default size
791 is set in the kernel config file.
793 lp=0 [LP] Specify parallel ports to use, e.g,
794 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
795 lp=reset first parallel port). 'lp=0' disables the
796 lp=auto printer driver. 'lp=reset' (which can be
797 specified in addition to the ports) causes
798 attached printers to be reset. Using
799 lp=port1,port2,... specifies the parallel ports
800 to associate lp devices with, starting with
801 lp0. A port specification may be 'none' to skip
802 that lp device, or a parport name such as
803 'parport0'. Specifying 'lp=auto' instead of a
804 port specification list means that device IDs
805 from each port should be examined, to see if
806 an IEEE 1284-compliant printer is attached; if
807 so, the driver will manage that printer.
808 See also header of drivers/char/lp.c.
811 Sets loops_per_jiffy to given constant, thus avoiding
812 time-consuming boot-time autodetection (up to 250 ms per
813 CPU). 0 enables autodetection (default). To determine
814 the correct value for your kernel, boot with normal
815 autodetection and see what value is printed. Note that
816 on SMP systems the preset will be applied to all CPUs,
817 which is likely to cause problems if your CPUs need
818 significantly divergent settings. An incorrect value
819 will cause delays in the kernel to be wrong, leading to
820 unpredictable I/O errors and other breakage. Although
821 unlikely, in the extreme case this might damage your
825 Format: <io>,<irq>,<dma>
827 mac5380= [HW,SCSI] Format:
828 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
830 mac53c9x= [HW,SCSI] Format:
831 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
833 machvec= [IA64] Force the use of a particular machine-vector
834 (machvec) in a generic kernel.
835 Example: machvec=hpzx1_swiotlb
837 mad16= [HW,OSS] Format:
838 <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
843 max_loop= [LOOP] Maximum number of loopback devices that can
847 maxcpus= [SMP] Maximum number of processors that an SMP kernel
850 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
851 equal to this physical address is ignored.
853 max_luns= [SCSI] Maximum number of LUNs to probe.
854 Should be between 1 and 2^32-1.
857 [SCSI] Maximum number of LUNs received.
858 Should be between 1 and 16384.
860 mca-pentium [BUGS=IA-32]
865 Format: <port>,<irq>,<mitsumi_bug_93_wait>
869 mce [IA-32] Machine Check Exception
871 md= [HW] RAID subsystems devices and level
872 See Documentation/md.txt.
875 Format: <first>,<last>
876 Specifies range of consoles to be captured by the MDA.
878 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
879 Amount of memory to be used when the kernel is not able
880 to see the whole system memory or for test.
881 [IA-32] Use together with memmap= to avoid physical
882 address space collisions. Without memmap= PCI devices
883 could be placed at addresses belonging to unused RAM.
885 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
888 memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact
889 E820 memory map, as specified by the user.
890 Such memmap=exactmap lines can be constructed based on
891 BIOS output or other requirements. See the memmap=nn@ss
894 memmap=nn[KMG]@ss[KMG]
895 [KNL] Force usage of a specific region of memory
896 Region of memory to be used, from ss to ss+nn.
898 memmap=nn[KMG]#ss[KMG]
899 [KNL,ACPI] Mark specific memory as ACPI data.
900 Region of memory to be used, from ss to ss+nn.
902 memmap=nn[KMG]$ss[KMG]
903 [KNL,ACPI] Mark specific memory as reserved.
904 Region of memory to be used, from ss to ss+nn.
906 meye.*= [HW] Set MotionEye Camera parameters
907 See Documentation/video4linux/meye.txt.
912 [KNL,SMP] debug: override scheduler migration costs
913 Format: <level-1-usecs>,<level-2-usecs>,...
914 This debugging option can be used to override the
915 default scheduler migration cost matrix. The numbers
916 are indexed by 'CPU domain distance'.
917 E.g. migration_cost=1000,2000,3000 on an SMT NUMA
918 box will set up an intra-core migration cost of
919 1 msec, an inter-core migration cost of 2 msecs,
920 and an inter-node migration cost of 3 msecs.
922 WARNING: using the wrong values here can break
923 scheduler performance, so it's only for scheduler
924 development purposes, not production environments.
927 [KNL,SMP] migration cost auto-detect verbosity
929 If a system's migration matrix reported at bootup
930 seems erroneous then this option can be used to
931 increase verbosity of the detection process.
932 We default to 0 (no extra messages), 1 will print
933 some more information, and 2 will be really
934 verbose (probably only useful if you also have a
935 serial console attached to the system).
938 [KNL,SMP] multiply/divide migration costs by a factor
940 This debug option can be used to proportionally
941 increase or decrease the auto-detected migration
942 costs for all entries of the migration matrix.
943 E.g. migration_factor=150 will increase migration
944 costs by 50%. (and thus the scheduler will be less
945 eager migrating cache-hot tasks)
946 migration_factor=80 will decrease migration costs
947 by 20%. (thus the scheduler will be more eager to
950 WARNING: using the wrong values here can break
951 scheduler performance, so it's only for scheduler
952 development purposes, not production environments.
955 [MOUSE] Maximum time between finger touching and
956 leaving touchpad surface for touch to be considered
957 a tap and be reported as a left button click (for
958 touchpads working in absolute mode only).
960 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
961 reporting absolute coordinates, such as tablets
962 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
963 reporting absolute coordinates, such as tablets
969 Format: <name>,<region-number>,<size>,<offset>
971 MTD_Region= [MTD] Format:
972 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
975 See drivers/mtd/cmdline.c.
977 mtouchusb.raw_coordinates=
978 [HW] Make the MicroTouch USB driver use raw coordinates
979 ('y', default) or cooked coordinates ('n')
981 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
984 See header of drivers/scsi/NCR_D700.c.
990 ncr53c400a= [HW,SCSI]
992 ncr53c406a= [HW,SCSI]
996 netdev= [NET] Network devices parameters
997 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
998 Note that mem_start is often overloaded to mean
999 something different and driver-specific.
1000 This usage is only documented in each driver source
1004 See Documentation/nfsroot.txt.
1006 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
1007 See Documentation/nfsroot.txt.
1009 nfs.callback_tcpport=
1010 [NFS] set the TCP port on which the NFSv4 callback
1011 channel should listen.
1013 nfs.idmap_cache_timeout=
1014 [NFS] set the maximum lifetime for idmapper cache
1017 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
1019 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
1020 emulation library even if a 387 maths coprocessor
1025 noapic [SMP,APIC] Tells the kernel to not make use of any
1026 IOAPICs that may be present in the system.
1028 noasync [HW,M68K] Disables async and sync negotiation for
1031 nobats [PPC] Do not use BATs for mapping kernel lowmem
1032 on "Classic" PPC cores.
1036 nodelayacct [KNL] Disable per-task delay accounting
1038 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1042 noexec [IA-32,X86-64]
1043 noexec=on: enable non-executable mappings (default)
1044 noexec=off: disable nn-executable mappings
1046 nofxsr [BUGS=IA-32] Disables x86 floating point extended
1047 register save and restore. The kernel will only save
1048 legacy floating-point registers on task switch.
1052 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
1053 instruction doesn't work correctly and not to
1056 nohalt [IA-64] Tells the kernel not to use the power saving
1057 function PAL_HALT_LIGHT when idle. This increases
1058 power-consumption. On the positive side, it reduces
1059 interrupt wake-up latency, which may improve performance
1060 in certain environments such as networked servers or
1063 noirqdebug [IA-32] Disables the code which attempts to detect and
1064 disable unhandled interrupt sources.
1066 noisapnp [ISAPNP] Disables ISA PnP code.
1068 noinitrd [RAM] Tells the kernel not to load any configured
1073 nolapic [IA-32,APIC] Do not enable or use the local APIC.
1075 noltlbs [PPC] Do not use large page/tlb entries for kernel
1076 lowmem mapping on PPC40x.
1078 nomca [IA-64] Disable machine check abort handling
1080 nomce [IA-32] Machine Check Exception
1082 noresidual [PPC] Don't use residual data on PReP machines.
1084 noresume [SWSUSP] Disables resume and restores original swap
1087 no-scroll [VGA] Disables scrollback.
1088 This is required for the Braillex ib80-piezo Braille
1089 reader made by F.H. Papenmeier (Germany).
1093 nosep [BUGS=IA-32] Disables x86 SYSENTER/SYSEXIT support.
1095 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
1097 nosync [HW,M68K] Disables sync negotiation for all devices.
1099 notsc [BUGS=IA-32] Disable Time Stamp Counter
1101 nousb [USB] Disable the USB subsystem
1105 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1111 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
1113 opl3sa2= [HW,OSS] Format:
1114 <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
1116 oprofile.timer= [HW]
1117 Use timer interrupt instead of performance counters
1122 osst= [HW,SCSI] SCSI Tape Driver
1123 Format: <buffer_size>,<write_threshold>
1124 See also Documentation/scsi/st.txt.
1126 panic= [KNL] Kernel behaviour on panic
1129 parkbd.port= [HW] Parallel port number the keyboard adapter is
1130 connected to, default is 0.
1132 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1133 0 for XT, 1 for AT (default is AT).
1136 parport= [HW,PPT] Specify parallel ports. 0 disables.
1137 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1138 Use 'auto' to force the driver to use any
1139 IRQ/DMA settings detected (the default is to
1140 ignore detected IRQ/DMA settings because of
1141 possible conflicts). You can specify the base
1142 address, IRQ, and DMA settings; IRQ and DMA
1143 should be numbers, or 'auto' (for using detected
1144 settings on that particular port), or 'nofifo'
1145 (to avoid using a FIFO even if it is detected).
1146 Parallel ports are assigned in the order they
1147 are specified on the command line, starting
1150 parport_init_mode= [HW,PPT]
1151 Configure VIA parallel port to operate in
1152 a specific mode. This is necessary on Pegasos
1153 computer where firmware has no options for setting
1154 up parallel port mode and sets it to spp.
1155 Currently this function knows 686a and 8231 chips.
1156 Format: [spp|ps2|epp|ecp|ecpepp]
1158 pas2= [HW,OSS] Format:
1159 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1162 See header of drivers/scsi/pas16.c.
1165 Halt all CPUs after the first oops has been printed for
1166 the specified number of seconds. This is to be used if
1167 your oopses keep scrolling off the screen.
1172 See header of drivers/block/paride/pcd.c.
1173 See also Documentation/paride.txt.
1175 pci=option[,option...] [PCI] various PCI subsystem options:
1176 off [IA-32] don't probe for the PCI bus
1177 bios [IA-32] force use of PCI BIOS, don't access
1178 the hardware directly. Use this if your machine
1179 has a non-standard PCI host bridge.
1180 nobios [IA-32] disallow use of PCI BIOS, only direct
1181 hardware access methods are allowed. Use this
1182 if you experience crashes upon bootup and you
1183 suspect they are caused by the BIOS.
1184 conf1 [IA-32] Force use of PCI Configuration
1186 conf2 [IA-32] Force use of PCI Configuration
1188 nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
1190 nomsi [MSI] If the PCI_MSI kernel config parameter is
1191 enabled, this kernel boot option can be used to
1192 disable the use of MSI interrupts system-wide.
1193 nosort [IA-32] Don't sort PCI devices according to
1194 order given by the PCI BIOS. This sorting is
1195 done to get a device order compatible with
1197 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1198 routing table. These calls are known to be buggy
1199 on several machines and they hang the machine
1200 when used, but on other computers it's the only
1201 way to get the interrupt routing table. Try
1202 this option if the kernel is unable to allocate
1203 IRQs or discover secondary PCI buses on your
1205 rom [IA-32] Assign address space to expansion ROMs.
1206 Use with caution as certain devices share
1207 address decoders between ROMs and other
1209 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be
1210 assigned automatically to PCI devices. You can
1211 make the kernel exclude IRQs of your ISA cards
1213 pirqaddr=0xAAAAA [IA-32] Specify the physical address
1214 of the PIRQ table (normally generated
1215 by the BIOS) if it is outside the
1216 F0000h-100000h range.
1217 lastbus=N [IA-32] Scan all buses thru bus #N. Can be
1218 useful if the kernel is unable to find your
1219 secondary buses and you want to tell it
1220 explicitly which ones they are.
1221 assign-busses [IA-32] Always assign all PCI bus
1222 numbers ourselves, overriding
1223 whatever the firmware may have done.
1224 usepirqmask [IA-32] Honor the possible IRQ mask stored
1225 in the BIOS $PIR table. This is needed on
1226 some systems with broken BIOSes, notably
1227 some HP Pavilion N5400 and Omnibook XE3
1228 notebooks. This will have no effect if ACPI
1229 IRQ routing is enabled.
1230 noacpi [IA-32] Do not use ACPI for IRQ routing
1231 or for PCI scanning.
1232 routeirq Do IRQ routing for all PCI devices.
1233 This is normally done in pci_enable_device(),
1234 so this option is a temporary workaround
1235 for broken drivers that don't call it.
1236 firmware [ARM] Do not re-enumerate the bus but instead
1237 just use the configuration from the
1238 bootloader. This is currently used on
1239 IXP2000 systems where the bus has to be
1240 configured a certain way for adjunct CPUs.
1241 noearly [X86] Don't do any early type 1 scanning.
1242 This might help on some broken boards which
1243 machine check when some devices' config space
1244 is read. But various workarounds are disabled
1245 and some IOMMU drivers will not work.
1246 pcmv= [HW,PCMCIA] BadgePAD 4
1249 See Documentation/paride.txt.
1251 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1254 See arch/parisc/kernel/pdc_chassis.c
1257 See Documentation/paride.txt.
1260 See Documentation/paride.txt.
1262 pirq= [SMP,APIC] Manual mp-table setup
1263 See Documentation/i386/IO-APIC.txt.
1265 plip= [PPT,NET] Parallel port network link
1266 Format: { parport<nr> | timid | 0 }
1267 See also Documentation/parport.txt.
1273 { on | off | curr | res | no-curr | no-res }
1276 [ISAPNP] Exclude IRQs for the autoconfiguration
1279 [ISAPNP] Exclude DMAs for the autoconfiguration
1281 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1282 Ranges are in pairs (I/O port base and size).
1285 [ISAPNP] Exclude memory regions for the
1287 Ranges are in pairs (memory base and size).
1289 profile= [KNL] Enable kernel profiling via /proc/profile
1290 Format: [schedule,]<number>
1291 Param: "schedule" - profile schedule points.
1292 Param: <number> - step/bucket size as a power of 2 for
1293 statistical time based profiling.
1295 processor.max_cstate= [HW,ACPI]
1296 Limit processor to maximum C-state
1297 max_cstate=9 overrides any DMI blacklist limit.
1299 processor.nocst [HW,ACPI]
1300 Ignore the _CST method to determine C-states,
1301 instead using the legacy FADT method
1303 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1305 See Documentation/ramdisk.txt.
1307 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1308 probe for; one of (bare|imps|exps|lifebook|any).
1309 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1311 psmouse.resetafter= [HW,MOUSE]
1312 Try to reset the device after so many bad packets
1315 [HW,MOUSE] Set desired mouse resolution, in dpi.
1316 psmouse.smartscroll=
1317 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
1318 0 = disabled, 1 = enabled (default).
1320 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1322 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1325 See Documentation/paride.txt.
1327 quiet= [KNL] Disable log messages
1332 See Documentation/md.txt.
1334 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1335 See Documentation/ramdisk.txt.
1337 ramdisk_blocksize= [RAM]
1338 See Documentation/ramdisk.txt.
1340 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1341 New name for the ramdisk parameter.
1342 See Documentation/ramdisk.txt.
1344 rcu.blimit= [KNL,BOOT] Set maximum number of finished
1345 RCU callbacks to process in one batch.
1347 rcu.qhimark= [KNL,BOOT] Set threshold of queued
1348 RCU callbacks over which batch limiting is disabled.
1350 rcu.qlowmark= [KNL,BOOT] Set threshold of queued
1351 RCU callbacks below which batch limiting is re-enabled.
1353 rcu.rsinterval= [KNL,BOOT,SMP] Set the number of additional
1354 RCU callbacks to queued before forcing reschedule
1359 Run specified binary instead of /init from the ramdisk,
1360 used for early userspace startup. See initrd.
1362 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1363 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1364 See arch/*/kernel/reboot.c.
1366 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1370 Reserves a hole at the top of the kernel virtual
1374 Specify the partition device for software suspend
1376 rhash_entries= [KNL,NET]
1377 Set number of hash buckets for route cache
1379 riscom8= [HW,SERIAL]
1380 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1382 ro [KNL] Mount root device read-only on boot
1384 root= [KNL] Root filesystem
1386 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1387 mount the root filesystem
1389 rootflags= [KNL] Set root filesystem mount option string
1391 rootfstype= [KNL] Set root filesystem type
1393 rw [KNL] Mount root device read-write on boot
1395 S [KNL] Run init in single mode
1398 See drivers/net/irda/sa1100_ir.c.
1401 Format: <io>,<irq>,<dma>,<dma2>
1403 sbni= [NET] Granch SBNI12 leased line adapter
1405 sbpcd= [HW,CD] Soundblaster CD adapter
1407 See a comment before function sbpcd_setup() in
1408 drivers/cdrom/sbpcd.c.
1410 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1411 Format: <io>[,<timeout>[,<isapnp>]]
1413 scsi_debug_*= [SCSI]
1414 See drivers/scsi/scsi_debug.c.
1416 scsi_default_dev_flags=
1417 [SCSI] SCSI default device flags
1420 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1421 Format: <vendor>:<model>:<flags>
1422 (flags are integer value)
1424 scsi_logging= [SCSI]
1426 selinux [SELINUX] Disable or enable SELinux at boot time.
1427 Format: { "0" | "1" }
1428 See security/selinux/Kconfig help text.
1431 Default value is set via kernel config option.
1432 If enabled at boot time, /selinux/disable can be used
1433 later to disable prior to initial policy load.
1435 selinux_compat_net =
1436 [SELINUX] Set initial selinux_compat_net flag value.
1437 Format: { "0" | "1" }
1438 0 -- use new secmark-based packet controls
1439 1 -- use legacy packet controls
1440 Default value is 0 (preferred).
1441 Value can be changed at runtime via
1442 /selinux/compat_net.
1444 serialnumber [BUGS=IA-32]
1446 sg_def_reserved_size= [SCSI]
1449 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1452 Maximal number of shapers.
1455 See header of drivers/scsi/sim710.c.
1461 Format: <io>,<irq>,<dma>
1462 See header of drivers/cdrom/sjcd.c.
1467 Format: <io1>[,<io2>[,...,<io8>]]
1469 snd-ad1816a= [HW,ALSA]
1471 snd-ad1848= [HW,ALSA]
1473 snd-ali5451= [HW,ALSA]
1475 snd-als100= [HW,ALSA]
1477 snd-als4000= [HW,ALSA]
1479 snd-azt2320= [HW,ALSA]
1481 snd-cmi8330= [HW,ALSA]
1483 snd-cmipci= [HW,ALSA]
1485 snd-cs4231= [HW,ALSA]
1487 snd-cs4232= [HW,ALSA]
1489 snd-cs4236= [HW,ALSA]
1491 snd-cs4281= [HW,ALSA]
1493 snd-cs46xx= [HW,ALSA]
1495 snd-dt019x= [HW,ALSA]
1497 snd-dummy= [HW,ALSA]
1499 snd-emu10k1= [HW,ALSA]
1501 snd-ens1370= [HW,ALSA]
1503 snd-ens1371= [HW,ALSA]
1505 snd-es968= [HW,ALSA]
1507 snd-es1688= [HW,ALSA]
1509 snd-es18xx= [HW,ALSA]
1511 snd-es1938= [HW,ALSA]
1513 snd-es1968= [HW,ALSA]
1515 snd-fm801= [HW,ALSA]
1517 snd-gusclassic= [HW,ALSA]
1519 snd-gusextreme= [HW,ALSA]
1521 snd-gusmax= [HW,ALSA]
1525 snd-ice1712= [HW,ALSA]
1527 snd-intel8x0= [HW,ALSA]
1529 snd-interwave= [HW,ALSA]
1534 snd-korg1212= [HW,ALSA]
1536 snd-maestro3= [HW,ALSA]
1538 snd-mpu401= [HW,ALSA]
1540 snd-mtpav= [HW,ALSA]
1542 snd-nm256= [HW,ALSA]
1544 snd-opl3sa2= [HW,ALSA]
1552 snd-opti93x= [HW,ALSA]
1556 snd-rme32= [HW,ALSA]
1558 snd-rme96= [HW,ALSA]
1560 snd-rme9652= [HW,ALSA]
1566 snd-sbawe= [HW,ALSA]
1568 snd-serial= [HW,ALSA]
1570 snd-sgalaxy= [HW,ALSA]
1572 snd-sonicvibes= [HW,ALSA]
1577 snd-sun-cs4231= [HW,ALSA]
1579 snd-trident= [HW,ALSA]
1581 snd-usb-audio= [HW,ALSA,USB]
1583 snd-via82xx= [HW,ALSA]
1585 snd-virmidi= [HW,ALSA]
1587 snd-wavefront= [HW,ALSA]
1589 snd-ymfpci= [HW,ALSA]
1591 sonicvibes= [HW,OSS]
1595 Format: <io>[,<irq>]
1597 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1598 See Documentation/sonypi.txt
1600 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1601 See Documentation/specialix.txt.
1603 spia_io_base= [HW,MTD]
1609 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1611 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1612 See Documentation/scsi/st.txt.
1615 See header of drivers/scsi/seagate.c.
1619 Set the STI (builtin display/keyboard on the HP-PARISC
1620 machines) console (graphic card) which should be used
1621 as the initial boot-console.
1622 See also comment in drivers/video/console/sticore.c.
1625 See comment in drivers/video/console/sticore.c.
1628 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1630 swiotlb= [IA-64] Number of I/O TLB slabs
1634 sym53c416= [HW,SCSI]
1635 See header of drivers/scsi/sym53c416.c.
1638 See header of drivers/scsi/t128.c.
1642 thash_entries= [KNL,NET]
1643 Set number of hash buckets for TCP connection
1645 time Show timing data prefixed to each printk message line
1647 clocksource= [GENERIC_TIME] Override the default clocksource
1648 Override the default clocksource and use the clocksource
1649 with the name specified.
1651 tipar.timeout= [HW,PPT]
1652 Set communications timeout in tenths of a second
1655 tipar.delay= [HW,PPT]
1656 Set inter-bit delay in microseconds (default 10).
1659 See header of drivers/scsi/seagate.c.
1662 See comment before function dc390_setup() in
1663 drivers/scsi/tmscsim.c.
1667 trix= [HW,OSS] MediaTrix AudioTrix Pro
1669 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1671 tsdev.xres= [TS] Horizontal screen resolution.
1672 tsdev.yres= [TS] Vertical screen resolution.
1674 turbografx.map[2|3]= [HW,JOY]
1675 TurboGraFX parallel port interface
1677 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1678 See also Documentation/input/joystick-parport.txt
1680 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1681 See header of drivers/scsi/u14-34f.c.
1690 [USBHID] The interval which mice are to be polled at.
1693 vdso=1: enable VDSO (default)
1694 vdso=0: disable VDSO mapping
1696 video= [FB] Frame buffer configuration
1697 See Documentation/fb/modedb.txt.
1699 vga= [BOOT,IA-32] Select a particular video mode
1700 See Documentation/i386/boot.txt and
1701 Documentation/svga.txt.
1702 Use vga=ask for menu.
1703 This is actually a boot loader parameter; the value is
1704 passed to the kernel using a special protocol.
1706 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
1707 size of <nn>. This can be used to increase the
1708 minimum size (128MB on x86). It can also be used to
1709 decrease the size and leave more room for directly
1712 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
1715 vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
1718 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
1721 waveartist= [HW,OSS]
1722 Format: <io>,<irq>,<dma>,<dma2>
1725 See header of drivers/scsi/wd33c93.c.
1728 See header of drivers/scsi/wd7000.c.
1731 See Documentation/watchdog/watchdog.txt.
1733 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1734 xd_geo= See header of drivers/block/xd.c.
1736 xirc2ps_cs= [NET,PCMCIA]
1738 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1740 norandmaps Don't use address space randomization
1741 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
1744 ______________________________________________________________________
1748 Add documentation for ALSA options.
1749 Add more DRM drivers.