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 text in square brackets at the beginning of the description states the
28 restrictions on the kernel for the said kernel parameter to be valid. The
29 restrictions referred to are that the relevant option is valid if:
31 ACPI ACPI support is enabled.
32 ALSA ALSA sound support is enabled.
33 APIC APIC support is enabled.
34 APM Advanced Power Management support is enabled.
35 AX25 Appropriate AX.25 support is enabled.
36 CD Appropriate CD support is enabled.
37 DEVFS devfs 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 NFS Appropriate NFS support is enabled.
64 OSS OSS sound support is enabled.
65 PARIDE The ParIDE subsystem is enabled.
66 PARISC The PA-RISC architecture is enabled.
67 PCI PCI bus support is enabled.
68 PCMCIA The PCMCIA subsystem is enabled.
69 PNP Plug & Play support is enabled.
70 PPC PowerPC architecture is enabled.
71 PPT Parallel port support is enabled.
72 PS2 Appropriate PS/2 support is enabled.
73 RAM RAM disk support is enabled.
74 S390 S390 architecture is enabled.
75 SCSI Appropriate SCSI support is enabled.
76 A lot of drivers has their options described inside of
78 SELINUX SELinux support is enabled.
79 SERIAL Serial support is enabled.
80 SMP The kernel is an SMP kernel.
81 SPARC Sparc architecture is enabled.
82 SWSUSP Software suspend is enabled.
83 TS Appropriate touchscreen support is enabled.
84 USB USB support is enabled.
85 USBHID USB Human Interface Device support is enabled.
86 V4L Video For Linux support is enabled.
87 VGA The VGA console has been enabled.
88 VT Virtual terminal support is enabled.
89 WDT Watchdog support is enabled.
90 XT IBM PC/XT MFM hard disk support is enabled.
91 X86-64 X86-64 architecture is enabled.
92 More X86-64 boot options can be found in
93 Documentation/x86_64/boot-options.txt .
95 In addition, the following text indicates that the option:
97 BUGS= Relates to possible processor bugs on the said processor.
98 KNL Is a kernel start-up parameter.
99 BOOT Is a boot loader parameter.
101 Parameters denoted with BOOT are actually interpreted by the boot
102 loader, and have no meaning to the kernel directly.
103 Do not modify the syntax of boot loader parameters without extreme
104 need or coordination with <Documentation/i386/boot.txt>.
106 Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
107 a trailing = on the name of any parameter states that that parameter will
108 be entered as an environment variable, whereas its absence indicates that
109 it will appear as a kernel argument readable via /proc/cmdline by programs
110 running once the system is up.
112 53c7xx= [HW,SCSI] Amiga SCSI controllers
113 See header of drivers/scsi/53c7xx.c.
114 See also Documentation/scsi/ncr53c7xx.txt.
116 acpi= [HW,ACPI] Advanced Configuration and Power Interface
117 Format: { force | off | ht | strict | noirq }
118 force -- enable ACPI if default was off
119 off -- disable ACPI if default was on
120 noirq -- do not use ACPI for IRQ routing
121 ht -- run only enough ACPI to enable Hyper Threading
122 strict -- Be less tolerant of platforms that are not
123 strictly ACPI specification compliant.
125 See also Documentation/pm.txt, pci=noacpi
127 acpi_sleep= [HW,ACPI] Sleep options
128 Format: { s3_bios, s3_mode }
129 See Documentation/power/video.txt
131 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
132 Format: { level | edge | high | low }
134 acpi_irq_balance [HW,ACPI]
135 ACPI will balance active IRQs
138 acpi_irq_nobalance [HW,ACPI]
139 ACPI will not move active IRQs (default)
142 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
144 Format: <irq>,<irq>...
146 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
147 Format: <irq>,<irq>...
149 acpi_osi= [HW,ACPI] empty param disables _OSI
151 acpi_serialize [HW,ACPI] force serialization of AML methods
153 acpi_skip_timer_override [HW,ACPI]
154 Recognize and ignore IRQ0/pin2 Interrupt Override.
155 For broken nForce2 BIOS resulting in XT-PIC timer.
157 acpi_dbg_layer= [HW,ACPI]
159 Each bit of the <int> indicates an ACPI debug layer,
160 1: enable, 0: disable. It is useful for boot time
161 debugging. After system has booted up, it can be set
162 via /proc/acpi/debug_layer.
164 acpi_dbg_level= [HW,ACPI]
166 Each bit of the <int> indicates an ACPI debug level,
167 1: enable, 0: disable. It is useful for boot time
168 debugging. After system has booted up, it can be set
169 via /proc/acpi/debug_level.
171 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
173 acpi_generic_hotkey [HW,ACPI]
174 Allow consolidated generic hotkey driver to
175 override platform specific driver.
176 See also Documentation/acpi-hotkey.txt.
178 enable_timer_pin_1 [i386,x86-64]
179 Enable PIN 1 of APIC timer
180 Can be useful to work around chipset bugs
181 (in particular on some ATI chipsets).
182 The kernel tries to set a reasonable default.
184 disable_timer_pin_1 [i386,x86-64]
185 Disable PIN 1 of APIC timer
186 Can be useful to work around chipset bugs.
189 Format: <io>,<irq>,<dma>,<dma2>
190 See also Documentation/sound/oss/AD1816.
193 Format: <io>,<irq>,<dma>,<dma2>,<type>
199 See header of drivers/scsi/advansys.c.
201 advwdt= [HW,WDT] Advantech WDT
202 Format: <iostart>,<iostop>
204 aedsp16= [HW,OSS] Audio Excel DSP 16
205 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
206 See also header of sound/oss/aedsp16.c.
209 See Documentation/scsi/aha152x.txt.
212 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
215 See Documentation/scsi/aic7xxx.txt.
218 See Documentation/scsi/aic79xx.txt.
220 amijoy.map= [HW,JOY] Amiga joystick support
221 Map of devices attached to JOY0DAT and JOY1DAT
223 See also Documentation/kernel/input/joystick.txt
225 analog.map= [HW,JOY] Analog joystick and gamepad support
226 Specifies type or capabilities of an analog joystick
227 connected to one of 16 gameports
228 Format: <type1>,<type2>,..<type16>
231 Power management functions (SPARCstation-4/5 + deriv.)
233 Disable APC CPU standby support. SPARCstation-Fox does
234 not play well with APC CPU idle - disable it if you have
235 APC and your system crashes randomly.
237 apic= [APIC,i386] Change the output verbosity whilst booting
238 Format: { quiet (default) | verbose | debug }
239 Change the amount of debugging information output
240 when initialising the APIC and IO-APIC components.
242 apm= [APM] Advanced Power Management
243 See header of arch/i386/kernel/apm.c.
248 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
249 Format: <io>,<irq>,<nodeID>
253 atarimouse= [HW,MOUSE] Atari Mouse
255 atascsi= [HW,SCSI] Atari SCSI
257 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
258 EzKey and similar keyboards
260 atkbd.reset= [HW] Reset keyboard during initialization
262 atkbd.set= [HW] Select keyboard code set
263 Format: <int> (2 = AT (default), 3 = PS/2)
265 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
268 atkbd.softraw= [HW] Choose between synthetic and real raw mode
269 Format: <bool> (0 = real, 1 = synthetic (default))
271 atkbd.softrepeat= [HW]
272 Use software keyboard repeat
276 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
277 Format: <io>,<memsize>,<isapnp>
279 aztcd= [HW,CD] Aztech CD268 CDROM driver
280 Format: <io>,0x79 (?)
282 baycom_epp= [HW,AX25]
285 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
287 See header of drivers/net/hamradio/baycom_par.c.
289 baycom_ser_fdx= [HW,AX25]
290 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
291 Format: <io>,<irq>,<mode>[,<baud>]
292 See header of drivers/net/hamradio/baycom_ser_fdx.c.
294 baycom_ser_hdx= [HW,AX25]
295 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
296 Format: <io>,<irq>,<mode>
297 See header of drivers/net/hamradio/baycom_ser_hdx.c.
299 blkmtd_device= [HW,MTD]
305 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
306 bttv.radio= Most important insmod options are available as
308 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
309 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
312 See drivers/scsi/BusLogic.c, comment before function
313 BusLogic_ParseDriverOptions().
315 c101= [NET] Moxa C101 synchronous serial card
317 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
318 Sometimes CPU hardware bugs make them report the cache
319 size incorrectly. The kernel will attempt work arounds
320 to fix known problems, but for some CPUs it is not
321 possible to determine what the correct size should be.
322 This option provides an override for these situations.
325 Format: <io>,<irq>[,PAS]
326 See header of drivers/cdrom/cdu31a.c.
328 chandev= [HW,NET] Generic channel device initialisation
330 checkreqprot [SELINUX] Set initial checkreqprot flag value.
331 Format: { "0" | "1" }
332 See security/selinux/Kconfig help text.
333 0 -- check protection applied by kernel (includes
334 any implied execute protection).
335 1 -- check protection requested by application.
336 Default value is set via a kernel config option.
337 Value can be changed at runtime via
338 /selinux/checkreqprot.
340 clock= [BUGS=IA-32,HW] gettimeofday timesource override.
341 Forces specified timesource (if avaliable) to be used
342 when calculating gettimeofday(). If specicified
343 timesource is not avalible, it defaults to PIT.
344 Format: { pit | tsc | cyclone | pmtmr }
348 [IA32/X86_64] Disable/Enable interrupt 0 timer routing
349 over the 8254 in addition to over the IO-APIC. The
350 kernel tries to set a sensible default.
352 hpet= [IA-32,HPET] option to disable HPET and use PIT.
356 Format: { auto | [<io>,][<irq>] }
358 com20020= [HW,NET] ARCnet - COM20020 chipset
360 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
362 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
366 ARCnet - COM90xx chipset (memory-mapped buffers)
367 Format: <io>[,<irq>[,<memstart>]]
369 condev= [HW,S390] console device
372 console= [KNL] Output console device and options.
374 tty<n> Use the virtual console device <n>.
378 Use the specified serial port. The options are of
379 the form "bbbbpnf", where "bbbb" is the baud rate,
380 "p" is parity ("n", "o", or "e"), "n" is number of
381 bits, and "f" is flow control ("r" for RTS or
382 omit it). Default is "9600n8".
384 See Documentation/serial-console.txt for more
386 Documentation/networking/netconsole.txt for an
389 uart,io,<addr>[,options]
390 uart,mmio,<addr>[,options]
391 Start an early, polled-mode console on the 8250/16550
392 UART at the specified I/O port or MMIO address,
393 switching to the matching ttyS device later. The
394 options are the same as for ttyS, above.
396 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
398 <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
401 Format: { parport<nr> | auto | none }
403 crashkernel=nn[KMG]@ss[KMG]
404 [KNL] Reserve a chunk of physical memory to
405 hold a kernel to switch to with kexec on panic.
408 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
413 cs89x0_media= [HW,NET]
414 Format: { rj45 | aui | bnc }
416 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
419 See header of drivers/s390/block/dasd_devmap.c.
421 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
422 (one device per port)
423 Format: <port#>,<type>
424 See also Documentation/input/joystick-parport.txt
426 debug [KNL] Enable kernel debugging (events log level).
429 Format: <area>[,<node>]
430 See also Documentation/networking/decnet.txt.
433 See Documentation/filesystems/devfs/boot-options.
436 Set number of hash buckets for dentry cache.
439 IO parameters + enable/disable command.
441 digiepca= [HW,SERIAL]
442 See drivers/char/README.epca and
443 Documentation/digiepca.txt.
445 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
447 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
449 dmasound= [HW,OSS] Sound subsystem buffers
455 earlyprintk= [IA-32,X86-64]
457 earlyprintk=serial[,ttySn[,baudrate]]
459 Append ",keep" to not disable it when the real console
462 Only vga or serial at a time, not both.
464 Currently only ttyS0 and ttyS1 are supported.
466 Interaction with the standard serial driver is not
469 The VGA output is eventually overwritten by the real
474 ec_intr= [HW,ACPI] ACPI Embedded Controller interrupt mode
477 non-0: interrupt mode (default)
484 Format: {"of[f]" | "sk[ipmbr]"}
485 See comment in arch/i386/boot/edd.S
488 Format: <id>,<membase>,<irq>
490 eisa_irq_edge= [PARISC,HW]
491 See header of drivers/parisc/eisa.c.
494 See comment before function elanfreq_setup() in
495 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
498 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
499 See Documentation/block/as-iosched.txt and
500 Documentation/block/deadline-iosched.txt for details.
502 elfcorehdr= [IA-32, X86_64]
503 Specifies physical address of start of kernel core
504 image elf header. Generally kexec loader will
505 pass this option to capture kernel.
506 See Documentation/kdump/kdump.txt for details.
508 enforcing [SELINUX] Set initial enforcing status.
510 See security/selinux/Kconfig help text.
511 0 -- permissive (log only, no denials).
512 1 -- enforcing (deny and log).
514 Value can be changed at runtime via /selinux/enforce.
517 Format: <lineout>[,<micbias>]
518 See also header of sound/oss/es1370.c.
521 Format: <spdif>,[<nomix>,[<amplifier>]]
522 See also header of sound/oss/es1371.c.
524 ether= [HW,NET] Ethernet cards parameters
525 This option is obsoleted by the "netdev=" option, which
526 has equivalent usage. See its documentation for details.
528 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
532 See header of drivers/scsi/fd_mcs.c.
535 See header of drivers/scsi/fdomain.c.
538 See Documentation/floppy.txt.
540 ftape= [HW] Floppy Tape subsystem debugging options.
541 See Documentation/ftape.txt.
544 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
545 support via parallel port (up to 5 devices per port)
546 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
547 See also Documentation/input/joystick-parport.txt
552 See header of drivers/scsi/gdth.c.
554 gpt [EFI] Forces disk with valid GPT signature but
555 invalid Protective MBR to be treated as GPT.
560 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
563 Format: <io>,<irq>,<dma>,<dma16>
567 hashdist= [KNL,NUMA] Large hashes allocated during boot
568 are distributed across NUMA nodes. Defaults on
569 for IA-64, off otherwise.
570 Format: 0 | 1 (for off | on)
572 hcl= [IA-64] SGI's Hardware Graph compatibility layer
574 hd= [EIDE] (E)IDE hard drive subsystem geometry
575 Format: <cyl>,<head>,<sect>
577 hd?= [HW] (E)IDE subsystem
578 hd?lun= See Documentation/ide.txt.
580 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
581 size of <nn>. This works even on boxes that have no
582 highmem otherwise. This also works to reduce highmem
583 size on bigger boxes.
586 See Documentation/isdn/README.HiSax.
588 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
590 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
592 i8042.direct [HW] Put keyboard port into non-translated mode
593 i8042.dumbkbd [HW] Pretend that controlled can only read data from
594 keyboard and can not control its state
595 (Don't attempt to blink the leds)
596 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
597 i8042.nokbd [HW] Don't check/create keyboard port
598 i8042.nomux [HW] Don't check presence of an active multiplexing
600 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
603 [HW] Frequency with which keyboard LEDs should blink
604 when kernel panics (default is 0.5 sec)
605 i8042.reset [HW] Reset the controller during init and cleanup
606 i8042.unlock [HW] Unlock (ignore) the keylock
610 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
611 indicates that the driver is running on unsupported
613 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
614 does not match list of supported models.
616 [HW] Report power status in /proc/i8k
617 (disabled by default)
618 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
621 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
622 See Documentation/mca.txt.
625 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
627 ide= [HW] (E)IDE subsystem
628 Format: ide=nodma or ide=doubler or ide=reverse
629 See Documentation/ide.txt.
631 ide?= [HW] (E)IDE subsystem
632 Format: ide?=noprobe or chipset specific parameters.
633 See Documentation/ide.txt.
635 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
636 See Documentation/ide.txt.
639 Format: idle=poll or idle=halt
642 Set number of hash buckets for inode cache.
645 See header of drivers/scsi/in2000.c.
649 Run specified binary instead of /sbin/init as init
652 initcall_debug [KNL] Trace initcalls as they are executed. Useful
653 for working out where the kernel is dying during
656 initrd= [BOOT] Specify the location of the initial ramdisk
658 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
661 combined_mode= [HW] control which driver uses IDE ports in combined
662 mode: legacy IDE driver, libata, or both
663 (in the libata case, libata.atapi_enabled=1 may be
664 useful as well). Note that using the ide or libata
665 options may affect your device naming (e.g. by
666 changing hdc to sdb).
667 Format: combined (default), ide, or libata
671 io7= [HW] IO7 for Marvel based alpha systems
672 See comment before marvel_specify_io7 in
673 arch/alpha/kernel/core_marvel.c.
676 See Documentation/nfsroot.txt.
678 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
679 See comment before ip2_setup() in drivers/char/ip2.c.
681 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
682 See header of drivers/scsi/ips.c.
685 When an interrupt is not handled search all handlers
686 for it. Intended to get systems with badly broken
690 When an interrupt is not handled search all handlers
691 for it. Also check all handlers each timer
692 interrupt. Intended to get systems with badly broken
696 Format: <RDP>,<reset>,<pci_scan>,<verbosity>
698 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
699 Format: <cpu number>,...,<cpu number>
700 This option can be used to specify one or more CPUs
701 to isolate from the general SMP balancing and scheduling
702 algorithms. The only way to move a process onto or off
703 an "isolated" CPU is via the CPU affinity syscalls.
704 <cpu number> begins at 0 and the maximum value is
705 "number of CPUs in system - 1".
707 This option is the preferred way to isolate CPUs. The
708 alternative -- manually setting the CPU mask of all
709 tasks in the system -- can cause problems and
710 suboptimal load balancer performance.
713 Format: <io>,<irq>,<dma>,<setup>
717 js= [HW,JOY] Analog joystick
718 See Documentation/input/joystick.txt.
722 kstack=N [IA-32,X86-64] Print N words from the kernel stack
727 lapic [IA-32,APIC] Enable the local APIC even if BIOS
730 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
731 Format: addr:<io>,irq:<irq>
733 llsc*= [IA64] See function print_params() in
734 arch/ia64/sn/kernel/llsc4.c.
736 load_ramdisk= [RAM] List of ramdisks to load from floppy
737 See Documentation/ramdisk.txt.
739 lockd.nlm_grace_period=P [NFS] Assign grace period.
742 lockd.nlm_tcpport=N [NFS] Assign TCP port.
745 lockd.nlm_timeout=T [NFS] Assign timeout value.
748 lockd.nlm_udpport=M [NFS] Assign UDP port.
751 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
754 loglevel= All Kernel Messages with a loglevel smaller than the
755 console loglevel will be printed to the console. It can
756 also be changed with klogd or other programs. The
757 loglevels are defined as follows:
759 0 (KERN_EMERG) system is unusable
760 1 (KERN_ALERT) action must be taken immediately
761 2 (KERN_CRIT) critical conditions
762 3 (KERN_ERR) error conditions
763 4 (KERN_WARNING) warning conditions
764 5 (KERN_NOTICE) normal but significant condition
765 6 (KERN_INFO) informational
766 7 (KERN_DEBUG) debug-level messages
768 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
769 Format: { n | nk | nM }
770 n must be a power of two. The default size
771 is set in the kernel config file.
773 lp=0 [LP] Specify parallel ports to use, e.g,
774 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
775 lp=reset first parallel port). 'lp=0' disables the
776 lp=auto printer driver. 'lp=reset' (which can be
777 specified in addition to the ports) causes
778 attached printers to be reset. Using
779 lp=port1,port2,... specifies the parallel ports
780 to associate lp devices with, starting with
781 lp0. A port specification may be 'none' to skip
782 that lp device, or a parport name such as
783 'parport0'. Specifying 'lp=auto' instead of a
784 port specification list means that device IDs
785 from each port should be examined, to see if
786 an IEEE 1284-compliant printer is attached; if
787 so, the driver will manage that printer.
788 See also header of drivers/char/lp.c.
791 Sets loops_per_jiffy to given constant, thus avoiding
792 time-consuming boot-time autodetection (up to 250 ms per
793 CPU). 0 enables autodetection (default). To determine
794 the correct value for your kernel, boot with normal
795 autodetection and see what value is printed. Note that
796 on SMP systems the preset will be applied to all CPUs,
797 which is likely to cause problems if your CPUs need
798 significantly divergent settings. An incorrect value
799 will cause delays in the kernel to be wrong, leading to
800 unpredictable I/O errors and other breakage. Although
801 unlikely, in the extreme case this might damage your
805 Format: <io>,<irq>,<dma>
807 mac5380= [HW,SCSI] Format:
808 <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
810 mac53c9x= [HW,SCSI] Format:
811 <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
813 machvec= [IA64] Force the use of a particular machine-vector
814 (machvec) in a generic kernel.
815 Example: machvec=hpzx1_swiotlb
817 mad16= [HW,OSS] Format:
818 <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
823 max_loop= [LOOP] Maximum number of loopback devices that can
827 maxcpus= [SMP] Maximum number of processors that an SMP kernel
830 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
831 equal to this physical address is ignored.
833 max_luns= [SCSI] Maximum number of LUNs to probe.
834 Should be between 1 and 2^32-1.
837 [SCSI] Maximum number of LUNs received.
838 Should be between 1 and 16384.
840 mca-pentium [BUGS=IA-32]
845 Format: <port>,<irq>,<mitsumi_bug_93_wait>
849 mce [IA-32] Machine Check Exception
851 md= [HW] RAID subsystems devices and level
852 See Documentation/md.txt.
855 Format: <first>,<last>
856 Specifies range of consoles to be captured by the MDA.
858 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
859 Amount of memory to be used when the kernel is not able
860 to see the whole system memory or for test.
861 [IA-32] Use together with memmap= to avoid physical
862 address space collisions. Without memmap= PCI devices
863 could be placed at addresses belonging to unused RAM.
865 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
868 memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact
869 E820 memory map, as specified by the user.
870 Such memmap=exactmap lines can be constructed based on
871 BIOS output or other requirements. See the memmap=nn@ss
874 memmap=nn[KMG]@ss[KMG]
875 [KNL] Force usage of a specific region of memory
876 Region of memory to be used, from ss to ss+nn.
878 memmap=nn[KMG]#ss[KMG]
879 [KNL,ACPI] Mark specific memory as ACPI data.
880 Region of memory to be used, from ss to ss+nn.
882 memmap=nn[KMG]$ss[KMG]
883 [KNL,ACPI] Mark specific memory as reserved.
884 Region of memory to be used, from ss to ss+nn.
886 meye.*= [HW] Set MotionEye Camera parameters
887 See Documentation/video4linux/meye.txt.
892 [KNL,SMP] debug: override scheduler migration costs
893 Format: <level-1-usecs>,<level-2-usecs>,...
894 This debugging option can be used to override the
895 default scheduler migration cost matrix. The numbers
896 are indexed by 'CPU domain distance'.
897 E.g. migration_cost=1000,2000,3000 on an SMT NUMA
898 box will set up an intra-core migration cost of
899 1 msec, an inter-core migration cost of 2 msecs,
900 and an inter-node migration cost of 3 msecs.
902 WARNING: using the wrong values here can break
903 scheduler performance, so it's only for scheduler
904 development purposes, not production environments.
907 [KNL,SMP] migration cost auto-detect verbosity
909 If a system's migration matrix reported at bootup
910 seems erroneous then this option can be used to
911 increase verbosity of the detection process.
912 We default to 0 (no extra messages), 1 will print
913 some more information, and 2 will be really
914 verbose (probably only useful if you also have a
915 serial console attached to the system).
918 [KNL,SMP] multiply/divide migration costs by a factor
920 This debug option can be used to proportionally
921 increase or decrease the auto-detected migration
922 costs for all entries of the migration matrix.
923 E.g. migration_factor=150 will increase migration
924 costs by 50%. (and thus the scheduler will be less
925 eager migrating cache-hot tasks)
926 migration_factor=80 will decrease migration costs
927 by 20%. (thus the scheduler will be more eager to
930 WARNING: using the wrong values here can break
931 scheduler performance, so it's only for scheduler
932 development purposes, not production environments.
935 [MOUSE] Maximum time between finger touching and
936 leaving touchpad surface for touch to be considered
937 a tap and be reported as a left button click (for
938 touchpads working in absolute mode only).
940 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
941 reporting absolute coordinates, such as tablets
942 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
943 reporting absolute coordinates, such as tablets
949 Format: <name>,<region-number>,<size>,<offset>
951 MTD_Region= [MTD] Format:
952 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
955 See drivers/mtd/cmdline.c.
957 mtouchusb.raw_coordinates=
958 [HW] Make the MicroTouch USB driver use raw coordinates
959 ('y', default) or cooked coordinates ('n')
961 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
964 See header of drivers/scsi/NCR_D700.c.
970 ncr53c400a= [HW,SCSI]
972 ncr53c406a= [HW,SCSI]
976 netdev= [NET] Network devices parameters
977 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
978 Note that mem_start is often overloaded to mean
979 something different and driver-specific.
980 This usage is only documented in each driver source
984 See Documentation/nfsroot.txt.
986 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
987 See Documentation/nfsroot.txt.
989 nfs.callback_tcpport=
990 [NFS] set the TCP port on which the NFSv4 callback
991 channel should listen.
993 nfs.idmap_cache_timeout=
994 [NFS] set the maximum lifetime for idmapper cache
997 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
999 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
1000 emulation library even if a 387 maths coprocessor
1005 noapic [SMP,APIC] Tells the kernel to not make use of any
1006 IOAPICs that may be present in the system.
1008 noasync [HW,M68K] Disables async and sync negotiation for
1011 nobats [PPC] Do not use BATs for mapping kernel lowmem
1012 on "Classic" PPC cores.
1016 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1020 noexec [IA-32,X86-64]
1021 noexec=on: enable non-executable mappings (default)
1022 noexec=off: disable nn-executable mappings
1024 nofxsr [BUGS=IA-32] Disables x86 floating point extended
1025 register save and restore. The kernel will only save
1026 legacy floating-point registers on task switch.
1030 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
1031 instruction doesn't work correctly and not to
1034 nohalt [IA-64] Tells the kernel not to use the power saving
1035 function PAL_HALT_LIGHT when idle. This increases
1036 power-consumption. On the positive side, it reduces
1037 interrupt wake-up latency, which may improve performance
1038 in certain environments such as networked servers or
1041 noirqdebug [IA-32] Disables the code which attempts to detect and
1042 disable unhandled interrupt sources.
1044 noisapnp [ISAPNP] Disables ISA PnP code.
1046 noinitrd [RAM] Tells the kernel not to load any configured
1051 nolapic [IA-32,APIC] Do not enable or use the local APIC.
1053 noltlbs [PPC] Do not use large page/tlb entries for kernel
1054 lowmem mapping on PPC40x.
1056 nomca [IA-64] Disable machine check abort handling
1058 nomce [IA-32] Machine Check Exception
1060 noresidual [PPC] Don't use residual data on PReP machines.
1062 noresume [SWSUSP] Disables resume and restores original swap
1065 no-scroll [VGA] Disables scrollback.
1066 This is required for the Braillex ib80-piezo Braille
1067 reader made by F.H. Papenmeier (Germany).
1071 nosep [BUGS=IA-32] Disables x86 SYSENTER/SYSEXIT support.
1073 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
1075 nosync [HW,M68K] Disables sync negotiation for all devices.
1077 notsc [BUGS=IA-32] Disable Time Stamp Counter
1079 nousb [USB] Disable the USB subsystem
1083 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1089 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
1091 opl3sa2= [HW,OSS] Format:
1092 <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
1094 oprofile.timer= [HW]
1095 Use timer interrupt instead of performance counters
1100 osst= [HW,SCSI] SCSI Tape Driver
1101 Format: <buffer_size>,<write_threshold>
1102 See also Documentation/scsi/st.txt.
1104 panic= [KNL] Kernel behaviour on panic
1107 parkbd.port= [HW] Parallel port number the keyboard adapter is
1108 connected to, default is 0.
1110 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
1111 0 for XT, 1 for AT (default is AT).
1114 parport= [HW,PPT] Specify parallel ports. 0 disables.
1115 Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] }
1116 Use 'auto' to force the driver to use any
1117 IRQ/DMA settings detected (the default is to
1118 ignore detected IRQ/DMA settings because of
1119 possible conflicts). You can specify the base
1120 address, IRQ, and DMA settings; IRQ and DMA
1121 should be numbers, or 'auto' (for using detected
1122 settings on that particular port), or 'nofifo'
1123 (to avoid using a FIFO even if it is detected).
1124 Parallel ports are assigned in the order they
1125 are specified on the command line, starting
1128 parport_init_mode= [HW,PPT]
1129 Configure VIA parallel port to operate in
1130 a specific mode. This is necessary on Pegasos
1131 computer where firmware has no options for setting
1132 up parallel port mode and sets it to spp.
1133 Currently this function knows 686a and 8231 chips.
1134 Format: [spp|ps2|epp|ecp|ecpepp]
1136 pas2= [HW,OSS] Format:
1137 <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1140 See header of drivers/scsi/pas16.c.
1143 Halt all CPUs after the first oops has been printed for
1144 the specified number of seconds. This is to be used if
1145 your oopses keep scrolling off the screen.
1150 See header of drivers/block/paride/pcd.c.
1151 See also Documentation/paride.txt.
1153 pci=option[,option...] [PCI] various PCI subsystem options:
1154 off [IA-32] don't probe for the PCI bus
1155 bios [IA-32] force use of PCI BIOS, don't access
1156 the hardware directly. Use this if your machine
1157 has a non-standard PCI host bridge.
1158 nobios [IA-32] disallow use of PCI BIOS, only direct
1159 hardware access methods are allowed. Use this
1160 if you experience crashes upon bootup and you
1161 suspect they are caused by the BIOS.
1162 conf1 [IA-32] Force use of PCI Configuration
1164 conf2 [IA-32] Force use of PCI Configuration
1166 nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
1168 nomsi [MSI] If the PCI_MSI kernel config parameter is
1169 enabled, this kernel boot option can be used to
1170 disable the use of MSI interrupts system-wide.
1171 nosort [IA-32] Don't sort PCI devices according to
1172 order given by the PCI BIOS. This sorting is
1173 done to get a device order compatible with
1175 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1176 routing table. These calls are known to be buggy
1177 on several machines and they hang the machine
1178 when used, but on other computers it's the only
1179 way to get the interrupt routing table. Try
1180 this option if the kernel is unable to allocate
1181 IRQs or discover secondary PCI buses on your
1183 rom [IA-32] Assign address space to expansion ROMs.
1184 Use with caution as certain devices share
1185 address decoders between ROMs and other
1187 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be
1188 assigned automatically to PCI devices. You can
1189 make the kernel exclude IRQs of your ISA cards
1191 pirqaddr=0xAAAAA [IA-32] Specify the physical address
1192 of the PIRQ table (normally generated
1193 by the BIOS) if it is outside the
1194 F0000h-100000h range.
1195 lastbus=N [IA-32] Scan all buses thru bus #N. Can be
1196 useful if the kernel is unable to find your
1197 secondary buses and you want to tell it
1198 explicitly which ones they are.
1199 assign-busses [IA-32] Always assign all PCI bus
1200 numbers ourselves, overriding
1201 whatever the firmware may have done.
1202 usepirqmask [IA-32] Honor the possible IRQ mask stored
1203 in the BIOS $PIR table. This is needed on
1204 some systems with broken BIOSes, notably
1205 some HP Pavilion N5400 and Omnibook XE3
1206 notebooks. This will have no effect if ACPI
1207 IRQ routing is enabled.
1208 noacpi [IA-32] Do not use ACPI for IRQ routing
1209 or for PCI scanning.
1210 routeirq Do IRQ routing for all PCI devices.
1211 This is normally done in pci_enable_device(),
1212 so this option is a temporary workaround
1213 for broken drivers that don't call it.
1214 firmware [ARM] Do not re-enumerate the bus but instead
1215 just use the configuration from the
1216 bootloader. This is currently used on
1217 IXP2000 systems where the bus has to be
1218 configured a certain way for adjunct CPUs.
1220 pcmv= [HW,PCMCIA] BadgePAD 4
1223 See Documentation/paride.txt.
1225 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1228 See arch/parisc/kernel/pdc_chassis.c
1231 See Documentation/paride.txt.
1234 See Documentation/paride.txt.
1236 pirq= [SMP,APIC] Manual mp-table setup
1237 See Documentation/i386/IO-APIC.txt.
1239 plip= [PPT,NET] Parallel port network link
1240 Format: { parport<nr> | timid | 0 }
1241 See also Documentation/parport.txt.
1247 { on | off | curr | res | no-curr | no-res }
1250 [ISAPNP] Exclude IRQs for the autoconfiguration
1253 [ISAPNP] Exclude DMAs for the autoconfiguration
1255 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1256 Ranges are in pairs (I/O port base and size).
1259 [ISAPNP] Exclude memory regions for the
1261 Ranges are in pairs (memory base and size).
1263 profile= [KNL] Enable kernel profiling via /proc/profile
1264 Format: [schedule,]<number>
1265 Param: "schedule" - profile schedule points.
1266 Param: <number> - step/bucket size as a power of 2 for
1267 statistical time based profiling.
1269 processor.max_cstate= [HW,ACPI]
1270 Limit processor to maximum C-state
1271 max_cstate=9 overrides any DMI blacklist limit.
1273 processor.nocst [HW,ACPI]
1274 Ignore the _CST method to determine C-states,
1275 instead using the legacy FADT method
1277 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1279 See Documentation/ramdisk.txt.
1281 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1282 probe for; one of (bare|imps|exps|lifebook|any).
1283 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1285 psmouse.resetafter= [HW,MOUSE]
1286 Try to reset the device after so many bad packets
1289 [HW,MOUSE] Set desired mouse resolution, in dpi.
1290 psmouse.smartscroll=
1291 [HW,MOUSE] Controls Logitech smartscroll autorepeat.
1292 0 = disabled, 1 = enabled (default).
1294 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1296 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1299 See Documentation/paride.txt.
1301 quiet= [KNL] Disable log messages
1306 See Documentation/md.txt.
1308 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1309 See Documentation/ramdisk.txt.
1311 ramdisk_blocksize= [RAM]
1312 See Documentation/ramdisk.txt.
1314 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1315 New name for the ramdisk parameter.
1316 See Documentation/ramdisk.txt.
1318 rcu.blimit= [KNL,BOOT] Set maximum number of finished
1319 RCU callbacks to process in one batch.
1321 rcu.qhimark= [KNL,BOOT] Set threshold of queued
1322 RCU callbacks over which batch limiting is disabled.
1324 rcu.qlowmark= [KNL,BOOT] Set threshold of queued
1325 RCU callbacks below which batch limiting is re-enabled.
1327 rcu.rsinterval= [KNL,BOOT,SMP] Set the number of additional
1328 RCU callbacks to queued before forcing reschedule
1333 Run specified binary instead of /init from the ramdisk,
1334 used for early userspace startup. See initrd.
1336 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1337 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1338 See arch/*/kernel/reboot.c.
1340 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1343 Specify the partition device for software suspend
1345 rhash_entries= [KNL,NET]
1346 Set number of hash buckets for route cache
1348 riscom8= [HW,SERIAL]
1349 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1351 ro [KNL] Mount root device read-only on boot
1353 root= [KNL] Root filesystem
1355 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1356 mount the root filesystem
1358 rootflags= [KNL] Set root filesystem mount option string
1360 rootfstype= [KNL] Set root filesystem type
1362 rw [KNL] Mount root device read-write on boot
1364 S [KNL] Run init in single mode
1367 See drivers/net/irda/sa1100_ir.c.
1370 Format: <io>,<irq>,<dma>,<dma2>
1372 sbni= [NET] Granch SBNI12 leased line adapter
1374 sbpcd= [HW,CD] Soundblaster CD adapter
1376 See a comment before function sbpcd_setup() in
1377 drivers/cdrom/sbpcd.c.
1379 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1380 Format: <io>[,<timeout>[,<isapnp>]]
1382 scsi_debug_*= [SCSI]
1383 See drivers/scsi/scsi_debug.c.
1385 scsi_default_dev_flags=
1386 [SCSI] SCSI default device flags
1389 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1390 Format: <vendor>:<model>:<flags>
1391 (flags are integer value)
1393 scsi_logging= [SCSI]
1395 selinux [SELINUX] Disable or enable SELinux at boot time.
1396 Format: { "0" | "1" }
1397 See security/selinux/Kconfig help text.
1400 Default value is set via kernel config option.
1401 If enabled at boot time, /selinux/disable can be used
1402 later to disable prior to initial policy load.
1404 serialnumber [BUGS=IA-32]
1406 sg_def_reserved_size= [SCSI]
1409 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1412 Maximal number of shapers.
1415 See header of drivers/scsi/sim710.c.
1421 Format: <io>,<irq>,<dma>
1422 See header of drivers/cdrom/sjcd.c.
1427 Format: <io1>[,<io2>[,...,<io8>]]
1429 snd-ad1816a= [HW,ALSA]
1431 snd-ad1848= [HW,ALSA]
1433 snd-ali5451= [HW,ALSA]
1435 snd-als100= [HW,ALSA]
1437 snd-als4000= [HW,ALSA]
1439 snd-azt2320= [HW,ALSA]
1441 snd-cmi8330= [HW,ALSA]
1443 snd-cmipci= [HW,ALSA]
1445 snd-cs4231= [HW,ALSA]
1447 snd-cs4232= [HW,ALSA]
1449 snd-cs4236= [HW,ALSA]
1451 snd-cs4281= [HW,ALSA]
1453 snd-cs46xx= [HW,ALSA]
1455 snd-dt019x= [HW,ALSA]
1457 snd-dummy= [HW,ALSA]
1459 snd-emu10k1= [HW,ALSA]
1461 snd-ens1370= [HW,ALSA]
1463 snd-ens1371= [HW,ALSA]
1465 snd-es968= [HW,ALSA]
1467 snd-es1688= [HW,ALSA]
1469 snd-es18xx= [HW,ALSA]
1471 snd-es1938= [HW,ALSA]
1473 snd-es1968= [HW,ALSA]
1475 snd-fm801= [HW,ALSA]
1477 snd-gusclassic= [HW,ALSA]
1479 snd-gusextreme= [HW,ALSA]
1481 snd-gusmax= [HW,ALSA]
1485 snd-ice1712= [HW,ALSA]
1487 snd-intel8x0= [HW,ALSA]
1489 snd-interwave= [HW,ALSA]
1494 snd-korg1212= [HW,ALSA]
1496 snd-maestro3= [HW,ALSA]
1498 snd-mpu401= [HW,ALSA]
1500 snd-mtpav= [HW,ALSA]
1502 snd-nm256= [HW,ALSA]
1504 snd-opl3sa2= [HW,ALSA]
1512 snd-opti93x= [HW,ALSA]
1516 snd-rme32= [HW,ALSA]
1518 snd-rme96= [HW,ALSA]
1520 snd-rme9652= [HW,ALSA]
1526 snd-sbawe= [HW,ALSA]
1528 snd-serial= [HW,ALSA]
1530 snd-sgalaxy= [HW,ALSA]
1532 snd-sonicvibes= [HW,ALSA]
1537 snd-sun-cs4231= [HW,ALSA]
1539 snd-trident= [HW,ALSA]
1541 snd-usb-audio= [HW,ALSA,USB]
1543 snd-via82xx= [HW,ALSA]
1545 snd-virmidi= [HW,ALSA]
1547 snd-wavefront= [HW,ALSA]
1549 snd-ymfpci= [HW,ALSA]
1551 sonicvibes= [HW,OSS]
1555 Format: <io>[,<irq>]
1557 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1558 See Documentation/sonypi.txt
1560 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1561 See Documentation/specialix.txt.
1563 spia_io_base= [HW,MTD]
1569 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1571 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1572 See Documentation/scsi/st.txt.
1575 See header of drivers/scsi/seagate.c.
1579 Set the STI (builtin display/keyboard on the HP-PARISC
1580 machines) console (graphic card) which should be used
1581 as the initial boot-console.
1582 See also comment in drivers/video/console/sticore.c.
1585 See comment in drivers/video/console/sticore.c.
1588 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1590 swiotlb= [IA-64] Number of I/O TLB slabs
1594 sym53c416= [HW,SCSI]
1595 See header of drivers/scsi/sym53c416.c.
1598 See header of drivers/scsi/t128.c.
1602 thash_entries= [KNL,NET]
1603 Set number of hash buckets for TCP connection
1605 time Show timing data prefixed to each printk message line
1607 tipar.timeout= [HW,PPT]
1608 Set communications timeout in tenths of a second
1611 tipar.delay= [HW,PPT]
1612 Set inter-bit delay in microseconds (default 10).
1615 See header of drivers/scsi/seagate.c.
1618 See comment before function dc390_setup() in
1619 drivers/scsi/tmscsim.c.
1623 trix= [HW,OSS] MediaTrix AudioTrix Pro
1625 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1627 tsdev.xres= [TS] Horizontal screen resolution.
1628 tsdev.yres= [TS] Vertical screen resolution.
1630 turbografx.map[2|3]= [HW,JOY]
1631 TurboGraFX parallel port interface
1633 <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1634 See also Documentation/input/joystick-parport.txt
1636 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1637 See header of drivers/scsi/u14-34f.c.
1646 [USBHID] The interval which mice are to be polled at.
1648 video= [FB] Frame buffer configuration
1649 See Documentation/fb/modedb.txt.
1651 vga= [BOOT,IA-32] Select a particular video mode
1652 See Documentation/i386/boot.txt and
1653 Documentation/svga.txt.
1654 Use vga=ask for menu.
1655 This is actually a boot loader parameter; the value is
1656 passed to the kernel using a special protocol.
1658 vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
1659 size of <nn>. This can be used to increase the
1660 minimum size (128MB on x86). It can also be used to
1661 decrease the size and leave more room for directly
1668 waveartist= [HW,OSS]
1669 Format: <io>,<irq>,<dma>,<dma2>
1672 See header of drivers/scsi/wd33c93.c.
1675 See header of drivers/scsi/wd7000.c.
1678 See Documentation/watchdog/watchdog.txt.
1680 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1681 xd_geo= See header of drivers/block/xd.c.
1683 xirc2ps_cs= [NET,PCMCIA]
1685 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1687 norandmaps Don't use address space randomization
1688 Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
1691 ______________________________________________________________________
1695 Add documentation for ALSA options.
1696 Add more DRM drivers.