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 DEVFS devfs support is enabled.
39 DRM Direct Rendering Management support is enabled.
40 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
41 EFI EFI Partitioning (GPT) is enabled
42 EIDE EIDE/ATAPI support is enabled.
43 FB The frame buffer device is enabled.
44 HW Appropriate hardware is enabled.
45 IA-32 IA-32 aka i386 architecture is enabled.
46 IA-64 IA-64 architecture is enabled.
47 IOSCHED More than one I/O scheduler is enabled.
48 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
49 ISAPNP ISA PnP code is enabled.
50 ISDN Appropriate ISDN support is enabled.
51 JOY Appropriate joystick support is enabled.
52 LP Printer support is enabled.
53 LOOP Loopback device support is enabled.
54 M68k M68k architecture is enabled.
55 These options have more detailed description inside of
56 Documentation/m68k/kernel-options.txt.
57 MCA MCA bus support is enabled.
58 MDA MDA console support is enabled.
59 MOUSE Appropriate mouse support is enabled.
60 MSI Message Signaled Interrupts (PCI).
61 MTD MTD support is enabled.
62 NET Appropriate network support is enabled.
63 NUMA NUMA support is enabled.
64 GENERIC_TIME The generic timeofday code is enabled.
65 NFS Appropriate NFS support is enabled.
66 OSS OSS sound support is enabled.
67 PARIDE The ParIDE subsystem is enabled.
68 PARISC The PA-RISC architecture is enabled.
69 PCI PCI bus support is enabled.
70 PCMCIA The PCMCIA subsystem is enabled.
71 PNP Plug & Play support is enabled.
72 PPC PowerPC architecture is enabled.
73 PPT Parallel port support is enabled.
74 PS2 Appropriate PS/2 support is enabled.
75 RAM RAM disk support is enabled.
76 S390 S390 architecture is enabled.
77 SCSI Appropriate SCSI support is enabled.
78 A lot of drivers has their options described inside of
80 SELINUX SELinux support is enabled.
81 SERIAL Serial support is enabled.
82 SMP The kernel is an SMP kernel.
83 SPARC Sparc architecture is enabled.
84 SWSUSP Software suspend is enabled.
85 TS Appropriate touchscreen support is enabled.
86 USB USB support is enabled.
87 USBHID USB Human Interface Device support is enabled.
88 V4L Video For Linux support is enabled.
89 VGA The VGA console has been enabled.
90 VT Virtual terminal support is enabled.
91 WDT Watchdog support is enabled.
92 XT IBM PC/XT MFM hard disk support is enabled.
93 X86-64 X86-64 architecture is enabled.
94 More X86-64 boot options can be found in
95 Documentation/x86_64/boot-options.txt .
97 In addition, the following text indicates that the option:
99 BUGS= Relates to possible processor bugs on the said processor.
100 KNL Is a kernel start-up parameter.
101 BOOT Is a boot loader parameter.
103 Parameters denoted with BOOT are actually interpreted by the boot
104 loader, and have no meaning to the kernel directly.
105 Do not modify the syntax of boot loader parameters without extreme
106 need or coordination with <Documentation/i386/boot.txt>.
108 Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
109 a trailing = on the name of any parameter states that that parameter will
110 be entered as an environment variable, whereas its absence indicates that
111 it will appear as a kernel argument readable via /proc/cmdline by programs
112 running once the system is up.
114 53c7xx= [HW,SCSI] Amiga SCSI controllers
115 See header of drivers/scsi/53c7xx.c.
116 See also Documentation/scsi/ncr53c7xx.txt.
118 acpi= [HW,ACPI] Advanced Configuration and Power Interface
119 Format: { force | off | ht | strict | noirq }
120 force -- enable ACPI if default was off
121 off -- disable ACPI if default was on
122 noirq -- do not use ACPI for IRQ routing
123 ht -- run only enough ACPI to enable Hyper Threading
124 strict -- Be less tolerant of platforms that are not
125 strictly ACPI specification compliant.
127 See also Documentation/pm.txt, pci=noacpi
129 acpi_sleep= [HW,ACPI] Sleep options
130 Format: { s3_bios, s3_mode }
131 See Documentation/power/video.txt
133 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
134 Format: { level | edge | high | low }
136 acpi_irq_balance [HW,ACPI]
137 ACPI will balance active IRQs
140 acpi_irq_nobalance [HW,ACPI]
141 ACPI will not move active IRQs (default)
144 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
146 Format: <irq>,<irq>...
148 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
149 Format: <irq>,<irq>...
151 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
152 Format: To spoof as Windows 98: ="Microsoft Windows"
154 acpi_osi= [HW,ACPI] empty param disables _OSI
156 acpi_serialize [HW,ACPI] force serialization of AML methods
158 acpi_skip_timer_override [HW,ACPI]
159 Recognize and ignore IRQ0/pin2 Interrupt Override.
160 For broken nForce2 BIOS resulting in XT-PIC timer.
162 acpi_dbg_layer= [HW,ACPI]
164 Each bit of the <int> indicates an ACPI debug layer,
165 1: enable, 0: disable. It is useful for boot time
166 debugging. After system has booted up, it can be set
167 via /proc/acpi/debug_layer.
169 acpi_dbg_level= [HW,ACPI]
171 Each bit of the <int> indicates an ACPI debug level,
172 1: enable, 0: disable. It is useful for boot time
173 debugging. After system has booted up, it can be set
174 via /proc/acpi/debug_level.
176 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
178 acpi_generic_hotkey [HW,ACPI]
179 Allow consolidated generic hotkey driver to
180 override platform specific driver.
181 See also Documentation/acpi-hotkey.txt.
183 acpi_pm_good [IA-32,X86-64]
184 Override the pmtimer bug detection: force the kernel
185 to assume that this machine's pmtimer latches its value
186 and always returns good values.
188 enable_timer_pin_1 [i386,x86-64]
189 Enable PIN 1 of APIC timer
190 Can be useful to work around chipset bugs
191 (in particular on some ATI chipsets).
192 The kernel tries to set a reasonable default.
194 disable_timer_pin_1 [i386,x86-64]
195 Disable PIN 1 of APIC timer
196 Can be useful to work around chipset bugs.
199 Format: <io>,<irq>,<dma>,<dma2>
200 See also Documentation/sound/oss/AD1816.
203 Format: <io>,<irq>,<dma>,<dma2>,<type>
209 See header of drivers/scsi/advansys.c.
211 advwdt= [HW,WDT] Advantech WDT
212 Format: <iostart>,<iostop>
214 aedsp16= [HW,OSS] Audio Excel DSP 16
215 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
216 See also header of sound/oss/aedsp16.c.
219 See Documentation/scsi/aha152x.txt.
222 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
225 See Documentation/scsi/aic7xxx.txt.
228 See Documentation/scsi/aic79xx.txt.
230 amijoy.map= [HW,JOY] Amiga joystick support
231 Map of devices attached to JOY0DAT and JOY1DAT
233 See also Documentation/kernel/input/joystick.txt
235 analog.map= [HW,JOY] Analog joystick and gamepad support
236 Specifies type or capabilities of an analog joystick
237 connected to one of 16 gameports
238 Format: <type1>,<type2>,..<type16>
241 Power management functions (SPARCstation-4/5 + deriv.)
243 Disable APC CPU standby support. SPARCstation-Fox does
244 not play well with APC CPU idle - disable it if you have
245 APC and your system crashes randomly.
247 apic= [APIC,i386] Change the output verbosity whilst booting
248 Format: { quiet (default) | verbose | debug }
249 Change the amount of debugging information output
250 when initialising the APIC and IO-APIC components.
252 apm= [APM] Advanced Power Management
253 See header of arch/i386/kernel/apm.c.
258 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
259 Format: <io>,<irq>,<nodeID>
263 atarimouse= [HW,MOUSE] Atari Mouse
265 atascsi= [HW,SCSI] Atari SCSI
267 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
268 EzKey and similar keyboards
270 atkbd.reset= [HW] Reset keyboard during initialization
272 atkbd.set= [HW] Select keyboard code set
273 Format: <int> (2 = AT (default), 3 = PS/2)
275 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
278 atkbd.softraw= [HW] Choose between synthetic and real raw mode
279 Format: <bool> (0 = real, 1 = synthetic (default))
281 atkbd.softrepeat= [HW]
282 Use software keyboard repeat
286 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
287 Format: <io>,<memsize>,<isapnp>
289 aztcd= [HW,CD] Aztech CD268 CDROM driver
290 Format: <io>,0x79 (?)
292 baycom_epp= [HW,AX25]
295 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
297 See header of drivers/net/hamradio/baycom_par.c.
299 baycom_ser_fdx= [HW,AX25]
300 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
301 Format: <io>,<irq>,<mode>[,<baud>]
302 See header of drivers/net/hamradio/baycom_ser_fdx.c.
304 baycom_ser_hdx= [HW,AX25]
305 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
306 Format: <io>,<irq>,<mode>
307 See header of drivers/net/hamradio/baycom_ser_hdx.c.
309 blkmtd_device= [HW,MTD]
315 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
316 bttv.radio= Most important insmod options are available as
318 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
319 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
322 See drivers/scsi/BusLogic.c, comment before function
323 BusLogic_ParseDriverOptions().
325 c101= [NET] Moxa C101 synchronous serial card
327 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
328 Sometimes CPU hardware bugs make them report the cache
329 size incorrectly. The kernel will attempt work arounds
330 to fix known problems, but for some CPUs it is not
331 possible to determine what the correct size should be.
332 This option provides an override for these situations.
335 Format: <io>,<irq>[,PAS]
336 See header of drivers/cdrom/cdu31a.c.
338 chandev= [HW,NET] Generic channel device initialisation
340 checkreqprot [SELINUX] Set initial checkreqprot flag value.
341 Format: { "0" | "1" }
342 See security/selinux/Kconfig help text.
343 0 -- check protection applied by kernel (includes
344 any implied execute protection).
345 1 -- check protection requested by application.
346 Default value is set via a kernel config option.
347 Value can be changed at runtime via
348 /selinux/checkreqprot.
350 clock= [BUGS=IA-32, HW] gettimeofday clocksource override.
352 Forces specified clocksource (if avaliable) to be used
353 when calculating gettimeofday(). If specified
354 clocksource is not avalible, it defaults to PIT.
355 Format: { pit | tsc | cyclone | pmtmr }
359 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
360 over the 8254 in addition to over the IO-APIC. The
361 kernel tries to set a sensible default.
363 hpet= [IA-32,HPET] option to disable HPET and use PIT.
367 Format: { auto | [<io>,][<irq>] }
369 com20020= [HW,NET] ARCnet - COM20020 chipset
371 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
373 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
377 ARCnet - COM90xx chipset (memory-mapped buffers)
378 Format: <io>[,<irq>[,<memstart>]]
380 condev= [HW,S390] console device
383 console= [KNL] Output console device and options.
385 tty<n> Use the virtual console device <n>.
389 Use the specified serial port. The options are of
390 the form "bbbbpnf", where "bbbb" is the baud rate,
391 "p" is parity ("n", "o", or "e"), "n" is number of
392 bits, and "f" is flow control ("r" for RTS or
393 omit it). Default is "9600n8".
395 See Documentation/serial-console.txt for more
397 Documentation/networking/netconsole.txt for an
400 uart,io,<addr>[,options]
401 uart,mmio,<addr>[,options]
402 Start an early, polled-mode console on the 8250/16550
403 UART at the specified I/O port or MMIO address,
404 switching to the matching ttyS device later. The
405 options are the same as for ttyS, above.
407 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
409 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
412 Format: { parport<nr> | auto | none }
414 crashkernel=nn[KMG]@ss[KMG]
415 [KNL] Reserve a chunk of physical memory to
416 hold a kernel to switch to with kexec on panic.
419 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
424 cs89x0_media= [HW,NET]
425 Format: { rj45 | aui | bnc }
427 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
430 See header of drivers/s390/block/dasd_devmap.c.
432 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
433 (one device per port)
434 Format: <port#>,<type>
435 See also Documentation/input/joystick-parport.txt
437 debug [KNL] Enable kernel debugging (events log level).
440 Format: <area>[,<node>]
441 See also Documentation/networking/decnet.txt.
444 See Documentation/filesystems/devfs/boot-options.
447 Set number of hash buckets for dentry cache.
450 IO parameters + enable/disable command.
452 digiepca= [HW,SERIAL]
453 See drivers/char/README.epca and
454 Documentation/digiepca.txt.
456 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
458 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
460 dmasound= [HW,OSS] Sound subsystem buffers
466 earlyprintk= [IA-32,X86-64]
468 earlyprintk=serial[,ttySn[,baudrate]]
470 Append ",keep" to not disable it when the real console
473 Only vga or serial at a time, not both.
475 Currently only ttyS0 and ttyS1 are supported.
477 Interaction with the standard serial driver is not
480 The VGA output is eventually overwritten by the real
485 ec_intr= [HW,ACPI] ACPI Embedded Controller interrupt mode
488 non-0: interrupt mode (default)
495 Format: {"of[f]" | "sk[ipmbr]"}
496 See comment in arch/i386/boot/edd.S
499 Format: <id>,<membase>,<irq>
501 eisa_irq_edge= [PARISC,HW]
502 See header of drivers/parisc/eisa.c.
505 See comment before function elanfreq_setup() in
506 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
509 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
510 See Documentation/block/as-iosched.txt and
511 Documentation/block/deadline-iosched.txt for details.
513 elfcorehdr= [IA-32, X86_64]
514 Specifies physical address of start of kernel core
515 image elf header. Generally kexec loader will
516 pass this option to capture kernel.
517 See Documentation/kdump/kdump.txt for details.
519 enforcing [SELINUX] Set initial enforcing status.
521 See security/selinux/Kconfig help text.
522 0 -- permissive (log only, no denials).
523 1 -- enforcing (deny and log).
525 Value can be changed at runtime via /selinux/enforce.
528 Format: <lineout>[,<micbias>]
529 See also header of sound/oss/es1370.c.
532 Format: <spdif>,[<nomix>,[<amplifier>]]
533 See also header of sound/oss/es1371.c.
535 ether= [HW,NET] Ethernet cards parameters
536 This option is obsoleted by the "netdev=" option, which
537 has equivalent usage. See its documentation for details.
539 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
543 See header of drivers/scsi/fd_mcs.c.
546 See header of drivers/scsi/fdomain.c.
549 See Documentation/floppy.txt.
551 ftape= [HW] Floppy Tape subsystem debugging options.
552 See Documentation/ftape.txt.
555 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
556 support via parallel port (up to 5 devices per port)
557 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
558 See also Documentation/input/joystick-parport.txt
563 See header of drivers/scsi/gdth.c.
565 gpt [EFI] Forces disk with valid GPT signature but
566 invalid Protective MBR to be treated as GPT.
571 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
574 Format: <io>,<irq>,<dma>,<dma16>
578 hashdist= [KNL,NUMA] Large hashes allocated during boot
579 are distributed across NUMA nodes. Defaults on
580 for IA-64, off otherwise.
581 Format: 0 | 1 (for off | on)
583 hcl= [IA-64] SGI's Hardware Graph compatibility layer
585 hd= [EIDE] (E)IDE hard drive subsystem geometry
586 Format: <cyl>,<head>,<sect>
588 hd?= [HW] (E)IDE subsystem
589 hd?lun= See Documentation/ide.txt.
591 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
592 size of <nn>. This works even on boxes that have no
593 highmem otherwise. This also works to reduce highmem
594 size on bigger boxes.
597 See Documentation/isdn/README.HiSax.
599 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
601 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
603 i8042.direct [HW] Put keyboard port into non-translated mode
604 i8042.dumbkbd [HW] Pretend that controlled can only read data from
605 keyboard and can not control its state
606 (Don't attempt to blink the leds)
607 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
608 i8042.nokbd [HW] Don't check/create keyboard port
609 i8042.nomux [HW] Don't check presence of an active multiplexing
611 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
614 [HW] Frequency with which keyboard LEDs should blink
615 when kernel panics (default is 0.5 sec)
616 i8042.reset [HW] Reset the controller during init and cleanup
617 i8042.unlock [HW] Unlock (ignore) the keylock
621 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
622 indicates that the driver is running on unsupported
624 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
625 does not match list of supported models.
627 [HW] Report power status in /proc/i8k
628 (disabled by default)
629 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
632 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
633 See Documentation/mca.txt.
636 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
638 ide= [HW] (E)IDE subsystem
639 Format: ide=nodma or ide=doubler or ide=reverse
640 See Documentation/ide.txt.
642 ide?= [HW] (E)IDE subsystem
643 Format: ide?=noprobe or chipset specific parameters.
644 See Documentation/ide.txt.
646 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
647 See Documentation/ide.txt.
650 Format: idle=poll or idle=halt
653 Set number of hash buckets for inode cache.
656 See header of drivers/scsi/in2000.c.
660 Run specified binary instead of /sbin/init as init
663 initcall_debug [KNL] Trace initcalls as they are executed. Useful
664 for working out where the kernel is dying during
667 initrd= [BOOT] Specify the location of the initial ramdisk
669 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
672 combined_mode= [HW] control which driver uses IDE ports in combined
673 mode: legacy IDE driver, libata, or both
674 (in the libata case, libata.atapi_enabled=1 may be
675 useful as well). Note that using the ide or libata
676 options may affect your device naming (e.g. by
677 changing hdc to sdb).
678 Format: combined (default), ide, or libata
682 io7= [HW] IO7 for Marvel based alpha systems
683 See comment before marvel_specify_io7 in
684 arch/alpha/kernel/core_marvel.c.
687 See Documentation/nfsroot.txt.
689 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
690 See comment before ip2_setup() in drivers/char/ip2.c.
692 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
693 See header of drivers/scsi/ips.c.
696 When an interrupt is not handled search all handlers
697 for it. Intended to get systems with badly broken
701 When an interrupt is not handled search all handlers
702 for it. Also check all handlers each timer
703 interrupt. Intended to get systems with badly broken
707 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
709 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
710 Format: <cpu number>,...,<cpu number>
711 This option can be used to specify one or more CPUs
712 to isolate from the general SMP balancing and scheduling
713 algorithms. The only way to move a process onto or off
714 an "isolated" CPU is via the CPU affinity syscalls.
715 <cpu number> begins at 0 and the maximum value is
716 "number of CPUs in system - 1".
718 This option is the preferred way to isolate CPUs. The
719 alternative -- manually setting the CPU mask of all
720 tasks in the system -- can cause problems and
721 suboptimal load balancer performance.
724 Format: <io>,<irq>,<dma>,<setup>
728 js= [HW,JOY] Analog joystick
729 See Documentation/input/joystick.txt.
733 kstack=N [IA-32,X86-64] Print N words from the kernel stack
738 lapic [IA-32,APIC] Enable the local APIC even if BIOS
741 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
742 Format: addr:<io>,irq:<irq>
744 llsc*= [IA64] See function print_params() in
745 arch/ia64/sn/kernel/llsc4.c.
747 load_ramdisk= [RAM] List of ramdisks to load from floppy
748 See Documentation/ramdisk.txt.
750 lockd.nlm_grace_period=P [NFS] Assign grace period.
753 lockd.nlm_tcpport=N [NFS] Assign TCP port.
756 lockd.nlm_timeout=T [NFS] Assign timeout value.
759 lockd.nlm_udpport=M [NFS] Assign UDP port.
762 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
765 loglevel= All Kernel Messages with a loglevel smaller than the
766 console loglevel will be printed to the console. It can
767 also be changed with klogd or other programs. The
768 loglevels are defined as follows:
770 0 (KERN_EMERG) system is unusable
771 1 (KERN_ALERT) action must be taken immediately
772 2 (KERN_CRIT) critical conditions
773 3 (KERN_ERR) error conditions
774 4 (KERN_WARNING) warning conditions
775 5 (KERN_NOTICE) normal but significant condition
776 6 (KERN_INFO) informational
777 7 (KERN_DEBUG) debug-level messages
779 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
780 Format: { n | nk | nM }
781 n must be a power of two. The default size
782 is set in the kernel config file.
784 lp=0 [LP] Specify parallel ports to use, e.g,
785 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
786 lp=reset first parallel port). 'lp=0' disables the
787 lp=auto printer driver. 'lp=reset' (which can be
788 specified in addition to the ports) causes
789 attached printers to be reset. Using
790 lp=port1,port2,... specifies the parallel ports
791 to associate lp devices with, starting with
792 lp0. A port specification may be 'none' to skip
793 that lp device, or a parport name such as
794 'parport0'. Specifying 'lp=auto' instead of a
795 port specification list means that device IDs
796 from each port should be examined, to see if
797 an IEEE 1284-compliant printer is attached; if
798 so, the driver will manage that printer.
799 See also header of drivers/char/lp.c.
802 Sets loops_per_jiffy to given constant, thus avoiding
803 time-consuming boot-time autodetection (up to 250 ms per
804 CPU). 0 enables autodetection (default). To determine
805 the correct value for your kernel, boot with normal
806 autodetection and see what value is printed. Note that
807 on SMP systems the preset will be applied to all CPUs,
808 which is likely to cause problems if your CPUs need
809 significantly divergent settings. An incorrect value
810 will cause delays in the kernel to be wrong, leading to
811 unpredictable I/O errors and other breakage. Although
812 unlikely, in the extreme case this might damage your
816 Format: <io>,<irq>,<dma>
818 mac5380= [HW,SCSI] Format:
819 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
821 mac53c9x= [HW,SCSI] Format:
822 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
824 machvec= [IA64] Force the use of a particular machine-vector
825 (machvec) in a generic kernel.
826 Example: machvec=hpzx1_swiotlb
828 mad16= [HW,OSS] Format:
829 <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
834 max_loop= [LOOP] Maximum number of loopback devices that can
838 maxcpus= [SMP] Maximum number of processors that an SMP kernel
841 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
842 equal to this physical address is ignored.
844 max_luns= [SCSI] Maximum number of LUNs to probe.
845 Should be between 1 and 2^32-1.
848 [SCSI] Maximum number of LUNs received.
849 Should be between 1 and 16384.
851 mca-pentium [BUGS=IA-32]
856 Format: <port>,<irq>,<mitsumi_bug_93_wait>
860 mce [IA-32] Machine Check Exception
862 md= [HW] RAID subsystems devices and level
863 See Documentation/md.txt.
866 Format: <first>,<last>
867 Specifies range of consoles to be captured by the MDA.
869 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
870 Amount of memory to be used when the kernel is not able
871 to see the whole system memory or for test.
872 [IA-32] Use together with memmap= to avoid physical
873 address space collisions. Without memmap= PCI devices
874 could be placed at addresses belonging to unused RAM.
876 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
879 memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact
880 E820 memory map, as specified by the user.
881 Such memmap=exactmap lines can be constructed based on
882 BIOS output or other requirements. See the memmap=nn@ss
885 memmap=nn[KMG]@ss[KMG]
886 [KNL] Force usage of a specific region of memory
887 Region of memory to be used, from ss to ss+nn.
889 memmap=nn[KMG]#ss[KMG]
890 [KNL,ACPI] Mark specific memory as ACPI data.
891 Region of memory to be used, from ss to ss+nn.
893 memmap=nn[KMG]$ss[KMG]
894 [KNL,ACPI] Mark specific memory as reserved.
895 Region of memory to be used, from ss to ss+nn.
897 meye.*= [HW] Set MotionEye Camera parameters
898 See Documentation/video4linux/meye.txt.
903 [KNL,SMP] debug: override scheduler migration costs
904 Format: <level-1-usecs>,<level-2-usecs>,...
905 This debugging option can be used to override the
906 default scheduler migration cost matrix. The numbers
907 are indexed by 'CPU domain distance'.
908 E.g. migration_cost=1000,2000,3000 on an SMT NUMA
909 box will set up an intra-core migration cost of
910 1 msec, an inter-core migration cost of 2 msecs,
911 and an inter-node migration cost of 3 msecs.
913 WARNING: using the wrong values here can break
914 scheduler performance, so it's only for scheduler
915 development purposes, not production environments.
918 [KNL,SMP] migration cost auto-detect verbosity
920 If a system's migration matrix reported at bootup
921 seems erroneous then this option can be used to
922 increase verbosity of the detection process.
923 We default to 0 (no extra messages), 1 will print
924 some more information, and 2 will be really
925 verbose (probably only useful if you also have a
926 serial console attached to the system).
929 [KNL,SMP] multiply/divide migration costs by a factor
931 This debug option can be used to proportionally
932 increase or decrease the auto-detected migration
933 costs for all entries of the migration matrix.
934 E.g. migration_factor=150 will increase migration
935 costs by 50%. (and thus the scheduler will be less
936 eager migrating cache-hot tasks)
937 migration_factor=80 will decrease migration costs
938 by 20%. (thus the scheduler will be more eager to
941 WARNING: using the wrong values here can break
942 scheduler performance, so it's only for scheduler
943 development purposes, not production environments.
946 [MOUSE] Maximum time between finger touching and
947 leaving touchpad surface for touch to be considered
948 a tap and be reported as a left button click (for
949 touchpads working in absolute mode only).
951 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
952 reporting absolute coordinates, such as tablets
953 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
954 reporting absolute coordinates, such as tablets
960 Format: <name>,<region-number>,<size>,<offset>
962 MTD_Region= [MTD] Format:
963 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
966 See drivers/mtd/cmdline.c.
968 mtouchusb.raw_coordinates=
969 [HW] Make the MicroTouch USB driver use raw coordinates
970 ('y', default) or cooked coordinates ('n')
972 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
975 See header of drivers/scsi/NCR_D700.c.
981 ncr53c400a= [HW,SCSI]
983 ncr53c406a= [HW,SCSI]
987 netdev= [NET] Network devices parameters
988 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
989 Note that mem_start is often overloaded to mean
990 something different and driver-specific.
991 This usage is only documented in each driver source
995 See Documentation/nfsroot.txt.
997 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
998 See Documentation/nfsroot.txt.
1000 nfs.callback_tcpport=
1001 [NFS] set the TCP port on which the NFSv4 callback
1002 channel should listen.
1004 nfs.idmap_cache_timeout=
1005 [NFS] set the maximum lifetime for idmapper cache
1008 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
1010 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
1011 emulation library even if a 387 maths coprocessor
1016 noapic [SMP,APIC] Tells the kernel to not make use of any
1017 IOAPICs that may be present in the system.
1019 noasync [HW,M68K] Disables async and sync negotiation for
1022 nobats [PPC] Do not use BATs for mapping kernel lowmem
1023 on "Classic" PPC cores.
1027 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1031 noexec [IA-32,X86-64]
1032 noexec=on: enable non-executable mappings (default)
1033 noexec=off: disable nn-executable mappings
1035 nofxsr [BUGS=IA-32] Disables x86 floating point extended
1036 register save and restore. The kernel will only save
1037 legacy floating-point registers on task switch.
1041 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
1042 instruction doesn't work correctly and not to
1045 nohalt [IA-64] Tells the kernel not to use the power saving
1046 function PAL_HALT_LIGHT when idle. This increases
1047 power-consumption. On the positive side, it reduces
1048 interrupt wake-up latency, which may improve performance
1049 in certain environments such as networked servers or
1052 noirqdebug [IA-32] Disables the code which attempts to detect and
1053 disable unhandled interrupt sources.
1055 noisapnp [ISAPNP] Disables ISA PnP code.
1057 noinitrd [RAM] Tells the kernel not to load any configured
1062 nolapic [IA-32,APIC] Do not enable or use the local APIC.
1064 noltlbs [PPC] Do not use large page/tlb entries for kernel
1065 lowmem mapping on PPC40x.
1067 nomca [IA-64] Disable machine check abort handling
1069 nomce [IA-32] Machine Check Exception
1071 noresidual [PPC] Don't use residual data on PReP machines.
1073 noresume [SWSUSP] Disables resume and restores original swap
1076 no-scroll [VGA] Disables scrollback.
1077 This is required for the Braillex ib80-piezo Braille
1078 reader made by F.H. Papenmeier (Germany).
1082 nosep [BUGS=IA-32] Disables x86 SYSENTER/SYSEXIT support.
1084 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
1086 nosync [HW,M68K] Disables sync negotiation for all devices.
1088 notsc [BUGS=IA-32] Disable Time Stamp Counter
1090 nousb [USB] Disable the USB subsystem
1094 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1100 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
1102 opl3sa2= [HW,OSS] Format:
1103 <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
1105 oprofile.timer= [HW]
1106 Use timer interrupt instead of performance counters
1111 osst= [HW,SCSI] SCSI Tape Driver
1112 Format: <buffer_size>,<write_threshold>
1113 See also Documentation/scsi/st.txt.
1115 panic= [KNL] Kernel behaviour on panic
1118 parkbd.port= [HW] Parallel port number the keyboard adapter is
1119 connected to, default is 0.
1121 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1122 0 for XT, 1 for AT (default is AT).
1125 parport= [HW,PPT] Specify parallel ports. 0 disables.
1126 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1127 Use 'auto' to force the driver to use any
1128 IRQ/DMA settings detected (the default is to
1129 ignore detected IRQ/DMA settings because of
1130 possible conflicts). You can specify the base
1131 address, IRQ, and DMA settings; IRQ and DMA
1132 should be numbers, or 'auto' (for using detected
1133 settings on that particular port), or 'nofifo'
1134 (to avoid using a FIFO even if it is detected).
1135 Parallel ports are assigned in the order they
1136 are specified on the command line, starting
1139 parport_init_mode= [HW,PPT]
1140 Configure VIA parallel port to operate in
1141 a specific mode. This is necessary on Pegasos
1142 computer where firmware has no options for setting
1143 up parallel port mode and sets it to spp.
1144 Currently this function knows 686a and 8231 chips.
1145 Format: [spp|ps2|epp|ecp|ecpepp]
1147 pas2= [HW,OSS] Format:
1148 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1151 See header of drivers/scsi/pas16.c.
1154 Halt all CPUs after the first oops has been printed for
1155 the specified number of seconds. This is to be used if
1156 your oopses keep scrolling off the screen.
1161 See header of drivers/block/paride/pcd.c.
1162 See also Documentation/paride.txt.
1164 pci=option[,option...] [PCI] various PCI subsystem options:
1165 off [IA-32] don't probe for the PCI bus
1166 bios [IA-32] force use of PCI BIOS, don't access
1167 the hardware directly. Use this if your machine
1168 has a non-standard PCI host bridge.
1169 nobios [IA-32] disallow use of PCI BIOS, only direct
1170 hardware access methods are allowed. Use this
1171 if you experience crashes upon bootup and you
1172 suspect they are caused by the BIOS.
1173 conf1 [IA-32] Force use of PCI Configuration
1175 conf2 [IA-32] Force use of PCI Configuration
1177 nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
1179 nomsi [MSI] If the PCI_MSI kernel config parameter is
1180 enabled, this kernel boot option can be used to
1181 disable the use of MSI interrupts system-wide.
1182 nosort [IA-32] Don't sort PCI devices according to
1183 order given by the PCI BIOS. This sorting is
1184 done to get a device order compatible with
1186 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1187 routing table. These calls are known to be buggy
1188 on several machines and they hang the machine
1189 when used, but on other computers it's the only
1190 way to get the interrupt routing table. Try
1191 this option if the kernel is unable to allocate
1192 IRQs or discover secondary PCI buses on your
1194 rom [IA-32] Assign address space to expansion ROMs.
1195 Use with caution as certain devices share
1196 address decoders between ROMs and other
1198 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be
1199 assigned automatically to PCI devices. You can
1200 make the kernel exclude IRQs of your ISA cards
1202 pirqaddr=0xAAAAA [IA-32] Specify the physical address
1203 of the PIRQ table (normally generated
1204 by the BIOS) if it is outside the
1205 F0000h-100000h range.
1206 lastbus=N [IA-32] Scan all buses thru bus #N. Can be
1207 useful if the kernel is unable to find your
1208 secondary buses and you want to tell it
1209 explicitly which ones they are.
1210 assign-busses [IA-32] Always assign all PCI bus
1211 numbers ourselves, overriding
1212 whatever the firmware may have done.
1213 usepirqmask [IA-32] Honor the possible IRQ mask stored
1214 in the BIOS $PIR table. This is needed on
1215 some systems with broken BIOSes, notably
1216 some HP Pavilion N5400 and Omnibook XE3
1217 notebooks. This will have no effect if ACPI
1218 IRQ routing is enabled.
1219 noacpi [IA-32] Do not use ACPI for IRQ routing
1220 or for PCI scanning.
1221 routeirq Do IRQ routing for all PCI devices.
1222 This is normally done in pci_enable_device(),
1223 so this option is a temporary workaround
1224 for broken drivers that don't call it.
1225 firmware [ARM] Do not re-enumerate the bus but instead
1226 just use the configuration from the
1227 bootloader. This is currently used on
1228 IXP2000 systems where the bus has to be
1229 configured a certain way for adjunct CPUs.
1231 pcmv= [HW,PCMCIA] BadgePAD 4
1234 See Documentation/paride.txt.
1236 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1239 See arch/parisc/kernel/pdc_chassis.c
1242 See Documentation/paride.txt.
1245 See Documentation/paride.txt.
1247 pirq= [SMP,APIC] Manual mp-table setup
1248 See Documentation/i386/IO-APIC.txt.
1250 plip= [PPT,NET] Parallel port network link
1251 Format: { parport<nr> | timid | 0 }
1252 See also Documentation/parport.txt.
1258 { on | off | curr | res | no-curr | no-res }
1261 [ISAPNP] Exclude IRQs for the autoconfiguration
1264 [ISAPNP] Exclude DMAs for the autoconfiguration
1266 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1267 Ranges are in pairs (I/O port base and size).
1270 [ISAPNP] Exclude memory regions for the
1272 Ranges are in pairs (memory base and size).
1274 profile= [KNL] Enable kernel profiling via /proc/profile
1275 Format: [schedule,]<number>
1276 Param: "schedule" - profile schedule points.
1277 Param: <number> - step/bucket size as a power of 2 for
1278 statistical time based profiling.
1280 processor.max_cstate= [HW,ACPI]
1281 Limit processor to maximum C-state
1282 max_cstate=9 overrides any DMI blacklist limit.
1284 processor.nocst [HW,ACPI]
1285 Ignore the _CST method to determine C-states,
1286 instead using the legacy FADT method
1288 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1290 See Documentation/ramdisk.txt.
1292 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1293 probe for; one of (bare|imps|exps|lifebook|any).
1294 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1296 psmouse.resetafter= [HW,MOUSE]
1297 Try to reset the device after so many bad packets
1300 [HW,MOUSE] Set desired mouse resolution, in dpi.
1301 psmouse.smartscroll=
1302 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
1303 0 = disabled, 1 = enabled (default).
1305 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1307 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1310 See Documentation/paride.txt.
1312 quiet= [KNL] Disable log messages
1317 See Documentation/md.txt.
1319 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1320 See Documentation/ramdisk.txt.
1322 ramdisk_blocksize= [RAM]
1323 See Documentation/ramdisk.txt.
1325 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1326 New name for the ramdisk parameter.
1327 See Documentation/ramdisk.txt.
1329 rcu.blimit= [KNL,BOOT] Set maximum number of finished
1330 RCU callbacks to process in one batch.
1332 rcu.qhimark= [KNL,BOOT] Set threshold of queued
1333 RCU callbacks over which batch limiting is disabled.
1335 rcu.qlowmark= [KNL,BOOT] Set threshold of queued
1336 RCU callbacks below which batch limiting is re-enabled.
1338 rcu.rsinterval= [KNL,BOOT,SMP] Set the number of additional
1339 RCU callbacks to queued before forcing reschedule
1344 Run specified binary instead of /init from the ramdisk,
1345 used for early userspace startup. See initrd.
1347 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1348 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1349 See arch/*/kernel/reboot.c.
1351 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1354 Specify the partition device for software suspend
1356 rhash_entries= [KNL,NET]
1357 Set number of hash buckets for route cache
1359 riscom8= [HW,SERIAL]
1360 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1362 ro [KNL] Mount root device read-only on boot
1364 root= [KNL] Root filesystem
1366 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1367 mount the root filesystem
1369 rootflags= [KNL] Set root filesystem mount option string
1371 rootfstype= [KNL] Set root filesystem type
1373 rw [KNL] Mount root device read-write on boot
1375 S [KNL] Run init in single mode
1378 See drivers/net/irda/sa1100_ir.c.
1381 Format: <io>,<irq>,<dma>,<dma2>
1383 sbni= [NET] Granch SBNI12 leased line adapter
1385 sbpcd= [HW,CD] Soundblaster CD adapter
1387 See a comment before function sbpcd_setup() in
1388 drivers/cdrom/sbpcd.c.
1390 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1391 Format: <io>[,<timeout>[,<isapnp>]]
1393 scsi_debug_*= [SCSI]
1394 See drivers/scsi/scsi_debug.c.
1396 scsi_default_dev_flags=
1397 [SCSI] SCSI default device flags
1400 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1401 Format: <vendor>:<model>:<flags>
1402 (flags are integer value)
1404 scsi_logging= [SCSI]
1406 selinux [SELINUX] Disable or enable SELinux at boot time.
1407 Format: { "0" | "1" }
1408 See security/selinux/Kconfig help text.
1411 Default value is set via kernel config option.
1412 If enabled at boot time, /selinux/disable can be used
1413 later to disable prior to initial policy load.
1415 selinux_compat_net =
1416 [SELINUX] Set initial selinux_compat_net flag value.
1417 Format: { "0" | "1" }
1418 0 -- use new secmark-based packet controls
1419 1 -- use legacy packet controls
1420 Default value is 0 (preferred).
1421 Value can be changed at runtime via
1422 /selinux/compat_net.
1424 serialnumber [BUGS=IA-32]
1426 sg_def_reserved_size= [SCSI]
1429 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1432 Maximal number of shapers.
1435 See header of drivers/scsi/sim710.c.
1441 Format: <io>,<irq>,<dma>
1442 See header of drivers/cdrom/sjcd.c.
1447 Format: <io1>[,<io2>[,...,<io8>]]
1449 snd-ad1816a= [HW,ALSA]
1451 snd-ad1848= [HW,ALSA]
1453 snd-ali5451= [HW,ALSA]
1455 snd-als100= [HW,ALSA]
1457 snd-als4000= [HW,ALSA]
1459 snd-azt2320= [HW,ALSA]
1461 snd-cmi8330= [HW,ALSA]
1463 snd-cmipci= [HW,ALSA]
1465 snd-cs4231= [HW,ALSA]
1467 snd-cs4232= [HW,ALSA]
1469 snd-cs4236= [HW,ALSA]
1471 snd-cs4281= [HW,ALSA]
1473 snd-cs46xx= [HW,ALSA]
1475 snd-dt019x= [HW,ALSA]
1477 snd-dummy= [HW,ALSA]
1479 snd-emu10k1= [HW,ALSA]
1481 snd-ens1370= [HW,ALSA]
1483 snd-ens1371= [HW,ALSA]
1485 snd-es968= [HW,ALSA]
1487 snd-es1688= [HW,ALSA]
1489 snd-es18xx= [HW,ALSA]
1491 snd-es1938= [HW,ALSA]
1493 snd-es1968= [HW,ALSA]
1495 snd-fm801= [HW,ALSA]
1497 snd-gusclassic= [HW,ALSA]
1499 snd-gusextreme= [HW,ALSA]
1501 snd-gusmax= [HW,ALSA]
1505 snd-ice1712= [HW,ALSA]
1507 snd-intel8x0= [HW,ALSA]
1509 snd-interwave= [HW,ALSA]
1514 snd-korg1212= [HW,ALSA]
1516 snd-maestro3= [HW,ALSA]
1518 snd-mpu401= [HW,ALSA]
1520 snd-mtpav= [HW,ALSA]
1522 snd-nm256= [HW,ALSA]
1524 snd-opl3sa2= [HW,ALSA]
1532 snd-opti93x= [HW,ALSA]
1536 snd-rme32= [HW,ALSA]
1538 snd-rme96= [HW,ALSA]
1540 snd-rme9652= [HW,ALSA]
1546 snd-sbawe= [HW,ALSA]
1548 snd-serial= [HW,ALSA]
1550 snd-sgalaxy= [HW,ALSA]
1552 snd-sonicvibes= [HW,ALSA]
1557 snd-sun-cs4231= [HW,ALSA]
1559 snd-trident= [HW,ALSA]
1561 snd-usb-audio= [HW,ALSA,USB]
1563 snd-via82xx= [HW,ALSA]
1565 snd-virmidi= [HW,ALSA]
1567 snd-wavefront= [HW,ALSA]
1569 snd-ymfpci= [HW,ALSA]
1571 sonicvibes= [HW,OSS]
1575 Format: <io>[,<irq>]
1577 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1578 See Documentation/sonypi.txt
1580 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1581 See Documentation/specialix.txt.
1583 spia_io_base= [HW,MTD]
1589 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1591 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1592 See Documentation/scsi/st.txt.
1595 See header of drivers/scsi/seagate.c.
1599 Set the STI (builtin display/keyboard on the HP-PARISC
1600 machines) console (graphic card) which should be used
1601 as the initial boot-console.
1602 See also comment in drivers/video/console/sticore.c.
1605 See comment in drivers/video/console/sticore.c.
1608 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1610 swiotlb= [IA-64] Number of I/O TLB slabs
1614 sym53c416= [HW,SCSI]
1615 See header of drivers/scsi/sym53c416.c.
1618 See header of drivers/scsi/t128.c.
1622 thash_entries= [KNL,NET]
1623 Set number of hash buckets for TCP connection
1625 time Show timing data prefixed to each printk message line
1627 clocksource= [GENERIC_TIME] Override the default clocksource
1628 Override the default clocksource and use the clocksource
1629 with the name specified.
1631 tipar.timeout= [HW,PPT]
1632 Set communications timeout in tenths of a second
1635 tipar.delay= [HW,PPT]
1636 Set inter-bit delay in microseconds (default 10).
1639 See header of drivers/scsi/seagate.c.
1642 See comment before function dc390_setup() in
1643 drivers/scsi/tmscsim.c.
1647 trix= [HW,OSS] MediaTrix AudioTrix Pro
1649 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1651 tsdev.xres= [TS] Horizontal screen resolution.
1652 tsdev.yres= [TS] Vertical screen resolution.
1654 turbografx.map[2|3]= [HW,JOY]
1655 TurboGraFX parallel port interface
1657 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1658 See also Documentation/input/joystick-parport.txt
1660 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1661 See header of drivers/scsi/u14-34f.c.
1670 [USBHID] The interval which mice are to be polled at.
1672 video= [FB] Frame buffer configuration
1673 See Documentation/fb/modedb.txt.
1675 vga= [BOOT,IA-32] Select a particular video mode
1676 See Documentation/i386/boot.txt and
1677 Documentation/svga.txt.
1678 Use vga=ask for menu.
1679 This is actually a boot loader parameter; the value is
1680 passed to the kernel using a special protocol.
1682 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
1683 size of <nn>. This can be used to increase the
1684 minimum size (128MB on x86). It can also be used to
1685 decrease the size and leave more room for directly
1692 waveartist= [HW,OSS]
1693 Format: <io>,<irq>,<dma>,<dma2>
1696 See header of drivers/scsi/wd33c93.c.
1699 See header of drivers/scsi/wd7000.c.
1702 See Documentation/watchdog/watchdog.txt.
1704 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1705 xd_geo= See header of drivers/block/xd.c.
1707 xirc2ps_cs= [NET,PCMCIA]
1709 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1711 norandmaps Don't use address space randomization
1712 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
1715 ______________________________________________________________________
1719 Add documentation for ALSA options.
1720 Add more DRM drivers.