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 The number of kernel parameters is not limited, but the length of the
114 complete command line (parameters including spaces etc.) is limited to
115 a fixed number of characters. This limit depends on the architecture
116 and is between 256 and 4096 characters. It is defined in the file
117 ./include/asm/setup.h as COMMAND_LINE_SIZE.
120 53c7xx= [HW,SCSI] Amiga SCSI controllers
121 See header of drivers/scsi/53c7xx.c.
122 See also Documentation/scsi/ncr53c7xx.txt.
124 acpi= [HW,ACPI] Advanced Configuration and Power Interface
125 Format: { force | off | ht | strict | noirq }
126 force -- enable ACPI if default was off
127 off -- disable ACPI if default was on
128 noirq -- do not use ACPI for IRQ routing
129 ht -- run only enough ACPI to enable Hyper Threading
130 strict -- Be less tolerant of platforms that are not
131 strictly ACPI specification compliant.
133 See also Documentation/pm.txt, pci=noacpi
135 acpi_sleep= [HW,ACPI] Sleep options
136 Format: { s3_bios, s3_mode }
137 See Documentation/power/video.txt
139 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
140 Format: { level | edge | high | low }
142 acpi_irq_balance [HW,ACPI]
143 ACPI will balance active IRQs
146 acpi_irq_nobalance [HW,ACPI]
147 ACPI will not move active IRQs (default)
150 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
152 Format: <irq>,<irq>...
154 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
155 Format: <irq>,<irq>...
157 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
158 Format: To spoof as Windows 98: ="Microsoft Windows"
160 acpi_osi= [HW,ACPI] empty param disables _OSI
162 acpi_serialize [HW,ACPI] force serialization of AML methods
164 acpi_skip_timer_override [HW,ACPI]
165 Recognize and ignore IRQ0/pin2 Interrupt Override.
166 For broken nForce2 BIOS resulting in XT-PIC timer.
167 acpi_use_timer_override [HW,ACPI}
168 Use timer override. For some broken Nvidia NF5 boards
169 that require a timer override, but don't have
172 acpi_dbg_layer= [HW,ACPI]
174 Each bit of the <int> indicates an ACPI debug layer,
175 1: enable, 0: disable. It is useful for boot time
176 debugging. After system has booted up, it can be set
177 via /proc/acpi/debug_layer.
179 acpi_dbg_level= [HW,ACPI]
181 Each bit of the <int> indicates an ACPI debug level,
182 1: enable, 0: disable. It is useful for boot time
183 debugging. After system has booted up, it can be set
184 via /proc/acpi/debug_level.
186 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
188 acpi_generic_hotkey [HW,ACPI]
189 Allow consolidated generic hotkey driver to
190 override platform specific driver.
191 See also Documentation/acpi-hotkey.txt.
193 acpi_pm_good [IA-32,X86-64]
194 Override the pmtimer bug detection: force the kernel
195 to assume that this machine's pmtimer latches its value
196 and always returns good values.
198 enable_timer_pin_1 [i386,x86-64]
199 Enable PIN 1 of APIC timer
200 Can be useful to work around chipset bugs
201 (in particular on some ATI chipsets).
202 The kernel tries to set a reasonable default.
204 disable_timer_pin_1 [i386,x86-64]
205 Disable PIN 1 of APIC timer
206 Can be useful to work around chipset bugs.
209 Format: <io>,<irq>,<dma>,<dma2>
210 See also Documentation/sound/oss/AD1816.
213 Format: <io>,<irq>,<dma>,<dma2>,<type>
219 See header of drivers/scsi/advansys.c.
221 advwdt= [HW,WDT] Advantech WDT
222 Format: <iostart>,<iostop>
224 aedsp16= [HW,OSS] Audio Excel DSP 16
225 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
226 See also header of sound/oss/aedsp16.c.
229 See Documentation/scsi/aha152x.txt.
232 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
235 See Documentation/scsi/aic7xxx.txt.
238 See Documentation/scsi/aic79xx.txt.
240 amijoy.map= [HW,JOY] Amiga joystick support
241 Map of devices attached to JOY0DAT and JOY1DAT
243 See also Documentation/kernel/input/joystick.txt
245 analog.map= [HW,JOY] Analog joystick and gamepad support
246 Specifies type or capabilities of an analog joystick
247 connected to one of 16 gameports
248 Format: <type1>,<type2>,..<type16>
251 Power management functions (SPARCstation-4/5 + deriv.)
253 Disable APC CPU standby support. SPARCstation-Fox does
254 not play well with APC CPU idle - disable it if you have
255 APC and your system crashes randomly.
257 apic= [APIC,i386] Change the output verbosity whilst booting
258 Format: { quiet (default) | verbose | debug }
259 Change the amount of debugging information output
260 when initialising the APIC and IO-APIC components.
262 apm= [APM] Advanced Power Management
263 See header of arch/i386/kernel/apm.c.
268 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
269 Format: <io>,<irq>,<nodeID>
273 atarimouse= [HW,MOUSE] Atari Mouse
275 atascsi= [HW,SCSI] Atari SCSI
277 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
278 EzKey and similar keyboards
280 atkbd.reset= [HW] Reset keyboard during initialization
282 atkbd.set= [HW] Select keyboard code set
283 Format: <int> (2 = AT (default), 3 = PS/2)
285 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
288 atkbd.softraw= [HW] Choose between synthetic and real raw mode
289 Format: <bool> (0 = real, 1 = synthetic (default))
291 atkbd.softrepeat= [HW]
292 Use software keyboard repeat
296 aztcd= [HW,CD] Aztech CD268 CDROM driver
297 Format: <io>,0x79 (?)
299 baycom_epp= [HW,AX25]
302 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
304 See header of drivers/net/hamradio/baycom_par.c.
306 baycom_ser_fdx= [HW,AX25]
307 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
308 Format: <io>,<irq>,<mode>[,<baud>]
309 See header of drivers/net/hamradio/baycom_ser_fdx.c.
311 baycom_ser_hdx= [HW,AX25]
312 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
313 Format: <io>,<irq>,<mode>
314 See header of drivers/net/hamradio/baycom_ser_hdx.c.
316 blkmtd_device= [HW,MTD]
322 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
323 bttv.radio= Most important insmod options are available as
325 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
326 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
329 See drivers/scsi/BusLogic.c, comment before function
330 BusLogic_ParseDriverOptions().
332 c101= [NET] Moxa C101 synchronous serial card
334 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
335 Sometimes CPU hardware bugs make them report the cache
336 size incorrectly. The kernel will attempt work arounds
337 to fix known problems, but for some CPUs it is not
338 possible to determine what the correct size should be.
339 This option provides an override for these situations.
342 Format: <io>,<irq>[,PAS]
343 See header of drivers/cdrom/cdu31a.c.
345 chandev= [HW,NET] Generic channel device initialisation
347 checkreqprot [SELINUX] Set initial checkreqprot flag value.
348 Format: { "0" | "1" }
349 See security/selinux/Kconfig help text.
350 0 -- check protection applied by kernel (includes
351 any implied execute protection).
352 1 -- check protection requested by application.
353 Default value is set via a kernel config option.
354 Value can be changed at runtime via
355 /selinux/checkreqprot.
357 clock= [BUGS=IA-32, HW] gettimeofday clocksource override.
359 Forces specified clocksource (if available) to be used
360 when calculating gettimeofday(). If specified
361 clocksource is not available, it defaults to PIT.
362 Format: { pit | tsc | cyclone | pmtmr }
366 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
367 over the 8254 in addition to over the IO-APIC. The
368 kernel tries to set a sensible default.
370 hpet= [IA-32,HPET] option to disable HPET and use PIT.
374 Format: { auto | [<io>,][<irq>] }
376 com20020= [HW,NET] ARCnet - COM20020 chipset
378 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
380 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
384 ARCnet - COM90xx chipset (memory-mapped buffers)
385 Format: <io>[,<irq>[,<memstart>]]
387 condev= [HW,S390] console device
390 console= [KNL] Output console device and options.
392 tty<n> Use the virtual console device <n>.
396 Use the specified serial port. The options are of
397 the form "bbbbpnf", where "bbbb" is the baud rate,
398 "p" is parity ("n", "o", or "e"), "n" is number of
399 bits, and "f" is flow control ("r" for RTS or
400 omit it). Default is "9600n8".
402 See Documentation/serial-console.txt for more
404 Documentation/networking/netconsole.txt for an
407 uart,io,<addr>[,options]
408 uart,mmio,<addr>[,options]
409 Start an early, polled-mode console on the 8250/16550
410 UART at the specified I/O port or MMIO address,
411 switching to the matching ttyS device later. The
412 options are the same as for ttyS, above.
414 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
416 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
419 Format: { parport<nr> | auto | none }
421 crashkernel=nn[KMG]@ss[KMG]
422 [KNL] Reserve a chunk of physical memory to
423 hold a kernel to switch to with kexec on panic.
426 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
431 cs89x0_media= [HW,NET]
432 Format: { rj45 | aui | bnc }
434 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
437 See header of drivers/s390/block/dasd_devmap.c.
439 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
440 (one device per port)
441 Format: <port#>,<type>
442 See also Documentation/input/joystick-parport.txt
444 debug [KNL] Enable kernel debugging (events log level).
447 [KNL] verbose self-tests
449 Print debugging info while doing the locking API
451 We default to 0 (no extra messages), setting it to
452 1 will print _a lot_ more information - normally
453 only useful to kernel developers.
456 Format: <area>[,<node>]
457 See also Documentation/networking/decnet.txt.
460 Set number of hash buckets for dentry cache.
463 IO parameters + enable/disable command.
465 digiepca= [HW,SERIAL]
466 See drivers/char/README.epca and
467 Documentation/digiepca.txt.
469 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
471 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
473 dmasound= [HW,OSS] Sound subsystem buffers
479 earlyprintk= [IA-32,X86-64]
481 earlyprintk=serial[,ttySn[,baudrate]]
483 Append ",keep" to not disable it when the real console
486 Only vga or serial at a time, not both.
488 Currently only ttyS0 and ttyS1 are supported.
490 Interaction with the standard serial driver is not
493 The VGA output is eventually overwritten by the real
498 ec_intr= [HW,ACPI] ACPI Embedded Controller interrupt mode
501 non-0: interrupt mode (default)
508 Format: {"of[f]" | "sk[ipmbr]"}
509 See comment in arch/i386/boot/edd.S
512 Format: <id>,<membase>,<irq>
514 eisa_irq_edge= [PARISC,HW]
515 See header of drivers/parisc/eisa.c.
518 See comment before function elanfreq_setup() in
519 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
522 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
523 See Documentation/block/as-iosched.txt and
524 Documentation/block/deadline-iosched.txt for details.
526 elfcorehdr= [IA-32, X86_64]
527 Specifies physical address of start of kernel core
528 image elf header. Generally kexec loader will
529 pass this option to capture kernel.
530 See Documentation/kdump/kdump.txt for details.
532 enforcing [SELINUX] Set initial enforcing status.
534 See security/selinux/Kconfig help text.
535 0 -- permissive (log only, no denials).
536 1 -- enforcing (deny and log).
538 Value can be changed at runtime via /selinux/enforce.
541 Format: <spdif>,[<nomix>,[<amplifier>]]
542 See also header of sound/oss/es1371.c.
544 ether= [HW,NET] Ethernet cards parameters
545 This option is obsoleted by the "netdev=" option, which
546 has equivalent usage. See its documentation for details.
548 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
552 See header of drivers/scsi/fd_mcs.c.
555 See header of drivers/scsi/fdomain.c.
558 See Documentation/floppy.txt.
561 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
562 support via parallel port (up to 5 devices per port)
563 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
564 See also Documentation/input/joystick-parport.txt
569 See header of drivers/scsi/gdth.c.
571 gpt [EFI] Forces disk with valid GPT signature but
572 invalid Protective MBR to be treated as GPT.
579 hashdist= [KNL,NUMA] Large hashes allocated during boot
580 are distributed across NUMA nodes. Defaults on
581 for IA-64, off otherwise.
582 Format: 0 | 1 (for off | on)
584 hcl= [IA-64] SGI's Hardware Graph compatibility layer
586 hd= [EIDE] (E)IDE hard drive subsystem geometry
587 Format: <cyl>,<head>,<sect>
589 hd?= [HW] (E)IDE subsystem
590 hd?lun= See Documentation/ide.txt.
592 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
593 size of <nn>. This works even on boxes that have no
594 highmem otherwise. This also works to reduce highmem
595 size on bigger boxes.
598 See Documentation/isdn/README.HiSax.
600 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
602 i8042.direct [HW] Put keyboard port into non-translated mode
603 i8042.dumbkbd [HW] Pretend that controller can only read data from
604 keyboard and cannot control its state
605 (Don't attempt to blink the leds)
606 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
607 i8042.nokbd [HW] Don't check/create keyboard port
608 i8042.nomux [HW] Don't check presence of an active multiplexing
610 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
613 [HW] Frequency with which keyboard LEDs should blink
614 when kernel panics (default is 0.5 sec)
615 i8042.reset [HW] Reset the controller during init and cleanup
616 i8042.unlock [HW] Unlock (ignore) the keylock
620 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
621 indicates that the driver is running on unsupported
623 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
624 does not match list of supported models.
626 [HW] Report power status in /proc/i8k
627 (disabled by default)
628 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
631 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
632 See Documentation/mca.txt.
635 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
637 ide= [HW] (E)IDE subsystem
638 Format: ide=nodma or ide=doubler or ide=reverse
639 See Documentation/ide.txt.
641 ide?= [HW] (E)IDE subsystem
642 Format: ide?=noprobe or chipset specific parameters.
643 See Documentation/ide.txt.
645 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
646 See Documentation/ide.txt.
649 Format: idle=poll or idle=halt
651 ignore_loglevel [KNL]
652 Ignore loglevel setting - this will print /all/
653 kernel messages to the console. Useful for debugging.
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.
720 <cpu number>,...,<cpu number>
722 <cpu number>-<cpu number> (must be a positive range in ascending order)
724 <cpu number>,...,<cpu number>-<cpu number>
725 This option can be used to specify one or more CPUs
726 to isolate from the general SMP balancing and scheduling
727 algorithms. The only way to move a process onto or off
728 an "isolated" CPU is via the CPU affinity syscalls.
729 <cpu number> begins at 0 and the maximum value is
730 "number of CPUs in system - 1".
732 This option is the preferred way to isolate CPUs. The
733 alternative -- manually setting the CPU mask of all
734 tasks in the system -- can cause problems and
735 suboptimal load balancer performance.
738 Format: <io>,<irq>,<dma>,<setup>
742 js= [HW,JOY] Analog joystick
743 See Documentation/input/joystick.txt.
747 kstack=N [IA-32,X86-64] Print N words from the kernel stack
752 lapic [IA-32,APIC] Enable the local APIC even if BIOS
755 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
756 Format: addr:<io>,irq:<irq>
758 llsc*= [IA64] See function print_params() in
759 arch/ia64/sn/kernel/llsc4.c.
761 load_ramdisk= [RAM] List of ramdisks to load from floppy
762 See Documentation/ramdisk.txt.
764 lockd.nlm_grace_period=P [NFS] Assign grace period.
767 lockd.nlm_tcpport=N [NFS] Assign TCP port.
770 lockd.nlm_timeout=T [NFS] Assign timeout value.
773 lockd.nlm_udpport=M [NFS] Assign UDP port.
776 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
779 loglevel= All Kernel Messages with a loglevel smaller than the
780 console loglevel will be printed to the console. It can
781 also be changed with klogd or other programs. The
782 loglevels are defined as follows:
784 0 (KERN_EMERG) system is unusable
785 1 (KERN_ALERT) action must be taken immediately
786 2 (KERN_CRIT) critical conditions
787 3 (KERN_ERR) error conditions
788 4 (KERN_WARNING) warning conditions
789 5 (KERN_NOTICE) normal but significant condition
790 6 (KERN_INFO) informational
791 7 (KERN_DEBUG) debug-level messages
793 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
794 Format: { n | nk | nM }
795 n must be a power of two. The default size
796 is set in the kernel config file.
798 lp=0 [LP] Specify parallel ports to use, e.g,
799 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
800 lp=reset first parallel port). 'lp=0' disables the
801 lp=auto printer driver. 'lp=reset' (which can be
802 specified in addition to the ports) causes
803 attached printers to be reset. Using
804 lp=port1,port2,... specifies the parallel ports
805 to associate lp devices with, starting with
806 lp0. A port specification may be 'none' to skip
807 that lp device, or a parport name such as
808 'parport0'. Specifying 'lp=auto' instead of a
809 port specification list means that device IDs
810 from each port should be examined, to see if
811 an IEEE 1284-compliant printer is attached; if
812 so, the driver will manage that printer.
813 See also header of drivers/char/lp.c.
816 Sets loops_per_jiffy to given constant, thus avoiding
817 time-consuming boot-time autodetection (up to 250 ms per
818 CPU). 0 enables autodetection (default). To determine
819 the correct value for your kernel, boot with normal
820 autodetection and see what value is printed. Note that
821 on SMP systems the preset will be applied to all CPUs,
822 which is likely to cause problems if your CPUs need
823 significantly divergent settings. An incorrect value
824 will cause delays in the kernel to be wrong, leading to
825 unpredictable I/O errors and other breakage. Although
826 unlikely, in the extreme case this might damage your
830 Format: <io>,<irq>,<dma>
832 mac5380= [HW,SCSI] Format:
833 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
835 mac53c9x= [HW,SCSI] Format:
836 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
838 machvec= [IA64] Force the use of a particular machine-vector
839 (machvec) in a generic kernel.
840 Example: machvec=hpzx1_swiotlb
842 max_loop= [LOOP] Maximum number of loopback devices that can
846 maxcpus= [SMP] Maximum number of processors that an SMP kernel
849 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
850 equal to this physical address is ignored.
852 max_luns= [SCSI] Maximum number of LUNs to probe.
853 Should be between 1 and 2^32-1.
856 [SCSI] Maximum number of LUNs received.
857 Should be between 1 and 16384.
859 mca-pentium [BUGS=IA-32]
864 Format: <port>,<irq>,<mitsumi_bug_93_wait>
868 mce [IA-32] Machine Check Exception
870 md= [HW] RAID subsystems devices and level
871 See Documentation/md.txt.
874 Format: <first>,<last>
875 Specifies range of consoles to be captured by the MDA.
877 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
878 Amount of memory to be used when the kernel is not able
879 to see the whole system memory or for test.
880 [IA-32] Use together with memmap= to avoid physical
881 address space collisions. Without memmap= PCI devices
882 could be placed at addresses belonging to unused RAM.
884 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
887 memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact
888 E820 memory map, as specified by the user.
889 Such memmap=exactmap lines can be constructed based on
890 BIOS output or other requirements. See the memmap=nn@ss
893 memmap=nn[KMG]@ss[KMG]
894 [KNL] Force usage of a specific region of memory
895 Region of memory to be used, from ss to ss+nn.
897 memmap=nn[KMG]#ss[KMG]
898 [KNL,ACPI] Mark specific memory as ACPI data.
899 Region of memory to be used, from ss to ss+nn.
901 memmap=nn[KMG]$ss[KMG]
902 [KNL,ACPI] Mark specific memory as reserved.
903 Region of memory to be used, from ss to ss+nn.
905 meye.*= [HW] Set MotionEye Camera parameters
906 See Documentation/video4linux/meye.txt.
911 [KNL,SMP] debug: override scheduler migration costs
912 Format: <level-1-usecs>,<level-2-usecs>,...
913 This debugging option can be used to override the
914 default scheduler migration cost matrix. The numbers
915 are indexed by 'CPU domain distance'.
916 E.g. migration_cost=1000,2000,3000 on an SMT NUMA
917 box will set up an intra-core migration cost of
918 1 msec, an inter-core migration cost of 2 msecs,
919 and an inter-node migration cost of 3 msecs.
921 WARNING: using the wrong values here can break
922 scheduler performance, so it's only for scheduler
923 development purposes, not production environments.
926 [KNL,SMP] migration cost auto-detect verbosity
928 If a system's migration matrix reported at bootup
929 seems erroneous then this option can be used to
930 increase verbosity of the detection process.
931 We default to 0 (no extra messages), 1 will print
932 some more information, and 2 will be really
933 verbose (probably only useful if you also have a
934 serial console attached to the system).
937 [KNL,SMP] multiply/divide migration costs by a factor
939 This debug option can be used to proportionally
940 increase or decrease the auto-detected migration
941 costs for all entries of the migration matrix.
942 E.g. migration_factor=150 will increase migration
943 costs by 50%. (and thus the scheduler will be less
944 eager migrating cache-hot tasks)
945 migration_factor=80 will decrease migration costs
946 by 20%. (thus the scheduler will be more eager to
949 WARNING: using the wrong values here can break
950 scheduler performance, so it's only for scheduler
951 development purposes, not production environments.
954 [MOUSE] Maximum time between finger touching and
955 leaving touchpad surface for touch to be considered
956 a tap and be reported as a left button click (for
957 touchpads working in absolute mode only).
959 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
960 reporting absolute coordinates, such as tablets
961 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
962 reporting absolute coordinates, such as tablets
968 Format: <name>,<region-number>,<size>,<offset>
970 MTD_Region= [MTD] Format:
971 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
974 See drivers/mtd/cmdline.c.
976 mtouchusb.raw_coordinates=
977 [HW] Make the MicroTouch USB driver use raw coordinates
978 ('y', default) or cooked coordinates ('n')
980 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
983 See header of drivers/scsi/NCR_D700.c.
989 ncr53c400a= [HW,SCSI]
991 ncr53c406a= [HW,SCSI]
995 netdev= [NET] Network devices parameters
996 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
997 Note that mem_start is often overloaded to mean
998 something different and driver-specific.
999 This usage is only documented in each driver source
1003 See Documentation/nfsroot.txt.
1005 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
1006 See Documentation/nfsroot.txt.
1008 nfs.callback_tcpport=
1009 [NFS] set the TCP port on which the NFSv4 callback
1010 channel should listen.
1012 nfs.idmap_cache_timeout=
1013 [NFS] set the maximum lifetime for idmapper cache
1016 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
1018 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
1019 emulation library even if a 387 maths coprocessor
1022 noaliencache [MM, NUMA] Disables the allcoation of alien caches in
1023 the slab allocator. Saves per-node memory, but will
1024 impact performance on real NUMA hardware.
1028 noapic [SMP,APIC] Tells the kernel to not make use of any
1029 IOAPICs that may be present in the system.
1031 noasync [HW,M68K] Disables async and sync negotiation for
1034 nobats [PPC] Do not use BATs for mapping kernel lowmem
1035 on "Classic" PPC cores.
1039 nodelayacct [KNL] Disable per-task delay accounting
1041 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1045 noexec [IA-32,X86-64]
1046 noexec=on: enable non-executable mappings (default)
1047 noexec=off: disable nn-executable mappings
1049 nofxsr [BUGS=IA-32] Disables x86 floating point extended
1050 register save and restore. The kernel will only save
1051 legacy floating-point registers on task switch.
1055 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
1056 instruction doesn't work correctly and not to
1059 nohalt [IA-64] Tells the kernel not to use the power saving
1060 function PAL_HALT_LIGHT when idle. This increases
1061 power-consumption. On the positive side, it reduces
1062 interrupt wake-up latency, which may improve performance
1063 in certain environments such as networked servers or
1066 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
1068 noirqdebug [IA-32] Disables the code which attempts to detect and
1069 disable unhandled interrupt sources.
1071 no_timer_check [IA-32,X86_64,APIC] Disables the code which tests for
1072 broken timer IRQ sources.
1074 noisapnp [ISAPNP] Disables ISA PnP code.
1076 noinitrd [RAM] Tells the kernel not to load any configured
1081 nolapic [IA-32,APIC] Do not enable or use the local APIC.
1083 noltlbs [PPC] Do not use large page/tlb entries for kernel
1084 lowmem mapping on PPC40x.
1086 nomca [IA-64] Disable machine check abort handling
1088 nomce [IA-32] Machine Check Exception
1090 noresidual [PPC] Don't use residual data on PReP machines.
1092 noresume [SWSUSP] Disables resume and restores original swap
1095 no-scroll [VGA] Disables scrollback.
1096 This is required for the Braillex ib80-piezo Braille
1097 reader made by F.H. Papenmeier (Germany).
1101 nosep [BUGS=IA-32] Disables x86 SYSENTER/SYSEXIT support.
1103 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
1105 nosync [HW,M68K] Disables sync negotiation for all devices.
1107 notsc [BUGS=IA-32] Disable Time Stamp Counter
1109 nousb [USB] Disable the USB subsystem
1113 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1118 opl3sa2= [HW,OSS] Format:
1119 <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
1121 oprofile.timer= [HW]
1122 Use timer interrupt instead of performance counters
1127 osst= [HW,SCSI] SCSI Tape Driver
1128 Format: <buffer_size>,<write_threshold>
1129 See also Documentation/scsi/st.txt.
1131 panic= [KNL] Kernel behaviour on panic
1134 parkbd.port= [HW] Parallel port number the keyboard adapter is
1135 connected to, default is 0.
1137 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1138 0 for XT, 1 for AT (default is AT).
1141 parport= [HW,PPT] Specify parallel ports. 0 disables.
1142 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1143 Use 'auto' to force the driver to use any
1144 IRQ/DMA settings detected (the default is to
1145 ignore detected IRQ/DMA settings because of
1146 possible conflicts). You can specify the base
1147 address, IRQ, and DMA settings; IRQ and DMA
1148 should be numbers, or 'auto' (for using detected
1149 settings on that particular port), or 'nofifo'
1150 (to avoid using a FIFO even if it is detected).
1151 Parallel ports are assigned in the order they
1152 are specified on the command line, starting
1155 parport_init_mode= [HW,PPT]
1156 Configure VIA parallel port to operate in
1157 a specific mode. This is necessary on Pegasos
1158 computer where firmware has no options for setting
1159 up parallel port mode and sets it to spp.
1160 Currently this function knows 686a and 8231 chips.
1161 Format: [spp|ps2|epp|ecp|ecpepp]
1163 pas2= [HW,OSS] Format:
1164 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1167 See header of drivers/scsi/pas16.c.
1170 Halt all CPUs after the first oops has been printed for
1171 the specified number of seconds. This is to be used if
1172 your oopses keep scrolling off the screen.
1177 See header of drivers/block/paride/pcd.c.
1178 See also Documentation/paride.txt.
1180 pci=option[,option...] [PCI] various PCI subsystem options:
1181 off [IA-32] don't probe for the PCI bus
1182 bios [IA-32] force use of PCI BIOS, don't access
1183 the hardware directly. Use this if your machine
1184 has a non-standard PCI host bridge.
1185 nobios [IA-32] disallow use of PCI BIOS, only direct
1186 hardware access methods are allowed. Use this
1187 if you experience crashes upon bootup and you
1188 suspect they are caused by the BIOS.
1189 conf1 [IA-32] Force use of PCI Configuration
1191 conf2 [IA-32] Force use of PCI Configuration
1193 nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
1195 nomsi [MSI] If the PCI_MSI kernel config parameter is
1196 enabled, this kernel boot option can be used to
1197 disable the use of MSI interrupts system-wide.
1198 nosort [IA-32] Don't sort PCI devices according to
1199 order given by the PCI BIOS. This sorting is
1200 done to get a device order compatible with
1202 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1203 routing table. These calls are known to be buggy
1204 on several machines and they hang the machine
1205 when used, but on other computers it's the only
1206 way to get the interrupt routing table. Try
1207 this option if the kernel is unable to allocate
1208 IRQs or discover secondary PCI buses on your
1210 rom [IA-32] Assign address space to expansion ROMs.
1211 Use with caution as certain devices share
1212 address decoders between ROMs and other
1214 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be
1215 assigned automatically to PCI devices. You can
1216 make the kernel exclude IRQs of your ISA cards
1218 pirqaddr=0xAAAAA [IA-32] Specify the physical address
1219 of the PIRQ table (normally generated
1220 by the BIOS) if it is outside the
1221 F0000h-100000h range.
1222 lastbus=N [IA-32] Scan all buses thru bus #N. Can be
1223 useful if the kernel is unable to find your
1224 secondary buses and you want to tell it
1225 explicitly which ones they are.
1226 assign-busses [IA-32] Always assign all PCI bus
1227 numbers ourselves, overriding
1228 whatever the firmware may have done.
1229 usepirqmask [IA-32] Honor the possible IRQ mask stored
1230 in the BIOS $PIR table. This is needed on
1231 some systems with broken BIOSes, notably
1232 some HP Pavilion N5400 and Omnibook XE3
1233 notebooks. This will have no effect if ACPI
1234 IRQ routing is enabled.
1235 noacpi [IA-32] Do not use ACPI for IRQ routing
1236 or for PCI scanning.
1237 routeirq Do IRQ routing for all PCI devices.
1238 This is normally done in pci_enable_device(),
1239 so this option is a temporary workaround
1240 for broken drivers that don't call it.
1241 firmware [ARM] Do not re-enumerate the bus but instead
1242 just use the configuration from the
1243 bootloader. This is currently used on
1244 IXP2000 systems where the bus has to be
1245 configured a certain way for adjunct CPUs.
1246 noearly [X86] Don't do any early type 1 scanning.
1247 This might help on some broken boards which
1248 machine check when some devices' config space
1249 is read. But various workarounds are disabled
1250 and some IOMMU drivers will not work.
1251 bfsort Sort PCI devices into breadth-first order.
1252 This sorting is done to get a device
1253 order compatible with older (<= 2.4) kernels.
1254 nobfsort Don't sort PCI devices into breadth-first order.
1256 pcmv= [HW,PCMCIA] BadgePAD 4
1259 See Documentation/paride.txt.
1261 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1264 See arch/parisc/kernel/pdc_chassis.c
1267 See Documentation/paride.txt.
1270 See Documentation/paride.txt.
1272 pirq= [SMP,APIC] Manual mp-table setup
1273 See Documentation/i386/IO-APIC.txt.
1275 plip= [PPT,NET] Parallel port network link
1276 Format: { parport<nr> | timid | 0 }
1277 See also Documentation/parport.txt.
1283 { on | off | curr | res | no-curr | no-res }
1286 [ISAPNP] Exclude IRQs for the autoconfiguration
1289 [ISAPNP] Exclude DMAs for the autoconfiguration
1291 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1292 Ranges are in pairs (I/O port base and size).
1295 [ISAPNP] Exclude memory regions for the
1297 Ranges are in pairs (memory base and size).
1299 profile= [KNL] Enable kernel profiling via /proc/profile
1300 Format: [schedule,]<number>
1301 Param: "schedule" - profile schedule points.
1302 Param: <number> - step/bucket size as a power of 2 for
1303 statistical time based profiling.
1304 Param: "sleep" - profile D-state sleeping (millisecs)
1306 processor.max_cstate= [HW,ACPI]
1307 Limit processor to maximum C-state
1308 max_cstate=9 overrides any DMI blacklist limit.
1310 processor.nocst [HW,ACPI]
1311 Ignore the _CST method to determine C-states,
1312 instead using the legacy FADT method
1314 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1316 See Documentation/ramdisk.txt.
1318 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1319 probe for; one of (bare|imps|exps|lifebook|any).
1320 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1322 psmouse.resetafter= [HW,MOUSE]
1323 Try to reset the device after so many bad packets
1326 [HW,MOUSE] Set desired mouse resolution, in dpi.
1327 psmouse.smartscroll=
1328 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
1329 0 = disabled, 1 = enabled (default).
1331 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1333 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1336 See Documentation/paride.txt.
1338 quiet [KNL] Disable most log messages
1343 See Documentation/md.txt.
1345 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1346 See Documentation/ramdisk.txt.
1348 ramdisk_blocksize= [RAM]
1349 See Documentation/ramdisk.txt.
1351 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1352 New name for the ramdisk parameter.
1353 See Documentation/ramdisk.txt.
1355 rcu.blimit= [KNL,BOOT] Set maximum number of finished
1356 RCU callbacks to process in one batch.
1358 rcu.qhimark= [KNL,BOOT] Set threshold of queued
1359 RCU callbacks over which batch limiting is disabled.
1361 rcu.qlowmark= [KNL,BOOT] Set threshold of queued
1362 RCU callbacks below which batch limiting is re-enabled.
1366 Run specified binary instead of /init from the ramdisk,
1367 used for early userspace startup. See initrd.
1369 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1370 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1371 See arch/*/kernel/reboot.c or arch/*/kernel/process.c
1373 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1377 Reserves a hole at the top of the kernel virtual
1380 reset_devices [KNL] Force drivers to reset the underlying device
1381 during initialization.
1384 Specify the partition device for software suspend
1386 resume_offset= [SWSUSP]
1387 Specify the offset from the beginning of the partition
1388 given by "resume=" at which the swap header is located,
1389 in <PAGE_SIZE> units (needed only for swap files).
1390 See Documentation/power/swsusp-and-swap-files.txt
1392 rhash_entries= [KNL,NET]
1393 Set number of hash buckets for route cache
1395 riscom8= [HW,SERIAL]
1396 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1398 ro [KNL] Mount root device read-only on boot
1400 root= [KNL] Root filesystem
1402 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1403 mount the root filesystem
1405 rootflags= [KNL] Set root filesystem mount option string
1407 rootfstype= [KNL] Set root filesystem type
1409 rw [KNL] Mount root device read-write on boot
1411 S [KNL] Run init in single mode
1414 See drivers/net/irda/sa1100_ir.c.
1417 Format: <io>,<irq>,<dma>,<dma2>
1419 sbni= [NET] Granch SBNI12 leased line adapter
1421 sbpcd= [HW,CD] Soundblaster CD adapter
1423 See a comment before function sbpcd_setup() in
1424 drivers/cdrom/sbpcd.c.
1426 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1427 Format: <io>[,<timeout>[,<isapnp>]]
1429 scsi_debug_*= [SCSI]
1430 See drivers/scsi/scsi_debug.c.
1432 scsi_default_dev_flags=
1433 [SCSI] SCSI default device flags
1436 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1437 Format: <vendor>:<model>:<flags>
1438 (flags are integer value)
1440 scsi_logging= [SCSI]
1442 scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are
1443 discovered. async scans them in kernel threads,
1444 allowing boot to proceed. none ignores them, expecting
1445 user space to do the scan.
1447 selinux [SELINUX] Disable or enable SELinux at boot time.
1448 Format: { "0" | "1" }
1449 See security/selinux/Kconfig help text.
1452 Default value is set via kernel config option.
1453 If enabled at boot time, /selinux/disable can be used
1454 later to disable prior to initial policy load.
1456 selinux_compat_net =
1457 [SELINUX] Set initial selinux_compat_net flag value.
1458 Format: { "0" | "1" }
1459 0 -- use new secmark-based packet controls
1460 1 -- use legacy packet controls
1461 Default value is 0 (preferred).
1462 Value can be changed at runtime via
1463 /selinux/compat_net.
1465 serialnumber [BUGS=IA-32]
1467 sg_def_reserved_size= [SCSI]
1470 Maximal number of shapers.
1473 See header of drivers/scsi/sim710.c.
1479 Format: <io>,<irq>,<dma>
1480 See header of drivers/cdrom/sjcd.c.
1485 Format: <io1>[,<io2>[,...,<io8>]]
1487 snd-ad1816a= [HW,ALSA]
1489 snd-ad1848= [HW,ALSA]
1491 snd-ali5451= [HW,ALSA]
1493 snd-als100= [HW,ALSA]
1495 snd-als4000= [HW,ALSA]
1497 snd-azt2320= [HW,ALSA]
1499 snd-cmi8330= [HW,ALSA]
1501 snd-cmipci= [HW,ALSA]
1503 snd-cs4231= [HW,ALSA]
1505 snd-cs4232= [HW,ALSA]
1507 snd-cs4236= [HW,ALSA]
1509 snd-cs4281= [HW,ALSA]
1511 snd-cs46xx= [HW,ALSA]
1513 snd-dt019x= [HW,ALSA]
1515 snd-dummy= [HW,ALSA]
1517 snd-emu10k1= [HW,ALSA]
1519 snd-ens1370= [HW,ALSA]
1521 snd-ens1371= [HW,ALSA]
1523 snd-es968= [HW,ALSA]
1525 snd-es1688= [HW,ALSA]
1527 snd-es18xx= [HW,ALSA]
1529 snd-es1938= [HW,ALSA]
1531 snd-es1968= [HW,ALSA]
1533 snd-fm801= [HW,ALSA]
1535 snd-gusclassic= [HW,ALSA]
1537 snd-gusextreme= [HW,ALSA]
1539 snd-gusmax= [HW,ALSA]
1543 snd-ice1712= [HW,ALSA]
1545 snd-intel8x0= [HW,ALSA]
1547 snd-interwave= [HW,ALSA]
1552 snd-korg1212= [HW,ALSA]
1554 snd-maestro3= [HW,ALSA]
1556 snd-mpu401= [HW,ALSA]
1558 snd-mtpav= [HW,ALSA]
1560 snd-nm256= [HW,ALSA]
1562 snd-opl3sa2= [HW,ALSA]
1570 snd-opti93x= [HW,ALSA]
1574 snd-rme32= [HW,ALSA]
1576 snd-rme96= [HW,ALSA]
1578 snd-rme9652= [HW,ALSA]
1584 snd-sbawe= [HW,ALSA]
1586 snd-serial= [HW,ALSA]
1588 snd-sgalaxy= [HW,ALSA]
1590 snd-sonicvibes= [HW,ALSA]
1595 snd-sun-cs4231= [HW,ALSA]
1597 snd-trident= [HW,ALSA]
1599 snd-usb-audio= [HW,ALSA,USB]
1601 snd-via82xx= [HW,ALSA]
1603 snd-virmidi= [HW,ALSA]
1605 snd-wavefront= [HW,ALSA]
1607 snd-ymfpci= [HW,ALSA]
1610 Format: <io>[,<irq>]
1612 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1613 See Documentation/sonypi.txt
1615 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1616 See Documentation/specialix.txt.
1618 spia_io_base= [HW,MTD]
1624 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1626 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1627 See Documentation/scsi/st.txt.
1630 See header of drivers/scsi/seagate.c.
1634 Set the STI (builtin display/keyboard on the HP-PARISC
1635 machines) console (graphic card) which should be used
1636 as the initial boot-console.
1637 See also comment in drivers/video/console/sticore.c.
1640 See comment in drivers/video/console/sticore.c.
1643 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1645 swiotlb= [IA-64] Number of I/O TLB slabs
1649 sym53c416= [HW,SCSI]
1650 See header of drivers/scsi/sym53c416.c.
1653 See header of drivers/scsi/t128.c.
1657 thash_entries= [KNL,NET]
1658 Set number of hash buckets for TCP connection
1660 time Show timing data prefixed to each printk message line
1662 clocksource= [GENERIC_TIME] Override the default clocksource
1663 Override the default clocksource and use the clocksource
1664 with the name specified.
1666 tipar.timeout= [HW,PPT]
1667 Set communications timeout in tenths of a second
1670 tipar.delay= [HW,PPT]
1671 Set inter-bit delay in microseconds (default 10).
1674 See header of drivers/scsi/seagate.c.
1677 See comment before function dc390_setup() in
1678 drivers/scsi/tmscsim.c.
1682 trix= [HW,OSS] MediaTrix AudioTrix Pro
1684 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1686 tsdev.xres= [TS] Horizontal screen resolution.
1687 tsdev.yres= [TS] Vertical screen resolution.
1689 turbografx.map[2|3]= [HW,JOY]
1690 TurboGraFX parallel port interface
1692 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1693 See also Documentation/input/joystick-parport.txt
1695 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1696 See header of drivers/scsi/u14-34f.c.
1705 [USBHID] The interval which mice are to be polled at.
1708 vdso=1: enable VDSO (default)
1709 vdso=0: disable VDSO mapping
1711 video= [FB] Frame buffer configuration
1712 See Documentation/fb/modedb.txt.
1714 vga= [BOOT,IA-32] Select a particular video mode
1715 See Documentation/i386/boot.txt and
1716 Documentation/svga.txt.
1717 Use vga=ask for menu.
1718 This is actually a boot loader parameter; the value is
1719 passed to the kernel using a special protocol.
1721 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
1722 size of <nn>. This can be used to increase the
1723 minimum size (128MB on x86). It can also be used to
1724 decrease the size and leave more room for directly
1727 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
1730 vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
1733 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
1736 waveartist= [HW,OSS]
1737 Format: <io>,<irq>,<dma>,<dma2>
1740 See header of drivers/scsi/wd33c93.c.
1743 See header of drivers/scsi/wd7000.c.
1746 See Documentation/watchdog/watchdog.txt.
1748 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1749 xd_geo= See header of drivers/block/xd.c.
1751 xirc2ps_cs= [NET,PCMCIA]
1753 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1755 norandmaps Don't use address space randomization
1756 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
1758 unwind_debug=N N > 0 will enable dwarf2 unwinder debugging
1759 This is useful to get more information why
1760 you got a "dwarf2 unwinder stuck"
1762 ______________________________________________________________________
1766 Add documentation for ALSA options.
1767 Add more DRM drivers.