kernel-parameters.txt 42 KB

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  1. February 2003 Kernel Parameters v2.5.59
  2. ~~~~~~~~~~~~~~~~~
  3. The following is a consolidated list of the kernel parameters as implemented
  4. (mostly) by the __setup() macro and sorted into English Dictionary order
  5. (defined as ignoring all punctuation and sorting digits before letters in a
  6. case insensitive manner), and with descriptions where known.
  7. Module parameters for loadable modules are specified only as the
  8. parameter name with optional '=' and value as appropriate, such as:
  9. modprobe usbcore blinkenlights=1
  10. Module parameters for modules that are built into the kernel image
  11. are specified on the kernel command line with the module name plus
  12. '.' plus parameter name, with '=' and value if appropriate, such as:
  13. usbcore.blinkenlights=1
  14. The text in square brackets at the beginning of the description state the
  15. restrictions on the kernel for the said kernel parameter to be valid. The
  16. restrictions referred to are that the relevant option is valid if:
  17. ACPI ACPI support is enabled.
  18. ALSA ALSA sound support is enabled.
  19. APIC APIC support is enabled.
  20. APM Advanced Power Management support is enabled.
  21. AX25 Appropriate AX.25 support is enabled.
  22. CD Appropriate CD support is enabled.
  23. DEVFS devfs support is enabled.
  24. DRM Direct Rendering Management support is enabled.
  25. EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
  26. EFI EFI Partitioning (GPT) is enabled
  27. EIDE EIDE/ATAPI support is enabled.
  28. FB The frame buffer device is enabled.
  29. HW Appropriate hardware is enabled.
  30. IA-32 IA-32 aka i386 architecture is enabled.
  31. IA-64 IA-64 architecture is enabled.
  32. IOSCHED More than one I/O scheduler is enabled.
  33. IP_PNP IP DCHP, BOOTP, or RARP is enabled.
  34. ISAPNP ISA PnP code is enabled.
  35. ISDN Appropriate ISDN support is enabled.
  36. JOY Appropriate joystick support is enabled.
  37. LP Printer support is enabled.
  38. LOOP Loopback device support is enabled.
  39. M68k M68k architecture is enabled.
  40. These options have more detailed description inside of
  41. Documentation/m68k/kernel-options.txt.
  42. MCA MCA bus support is enabled.
  43. MDA MDA console support is enabled.
  44. MOUSE Appropriate mouse support is enabled.
  45. MTD MTD support is enabled.
  46. NET Appropriate network support is enabled.
  47. NUMA NUMA support is enabled.
  48. NFS Appropriate NFS support is enabled.
  49. OSS OSS sound support is enabled.
  50. PARIDE The ParIDE subsystem is enabled.
  51. PARISC The PA-RISC architecture is enabled.
  52. PCI PCI bus support is enabled.
  53. PCMCIA The PCMCIA subsystem is enabled.
  54. PNP Plug & Play support is enabled.
  55. PPC PowerPC architecture is enabled.
  56. PPT Parallel port support is enabled.
  57. PS2 Appropriate PS/2 support is enabled.
  58. RAM RAM disk support is enabled.
  59. S390 S390 architecture is enabled.
  60. SCSI Appropriate SCSI support is enabled.
  61. A lot of drivers has their options described inside of
  62. Documentation/scsi/.
  63. SELINUX SELinux support is enabled.
  64. SERIAL Serial support is enabled.
  65. SMP The kernel is an SMP kernel.
  66. SPARC Sparc architecture is enabled.
  67. SWSUSP Software suspension is enabled.
  68. TS Appropriate touchscreen support is enabled.
  69. USB USB support is enabled.
  70. USBHID USB Human Interface Device support is enabled.
  71. V4L Video For Linux support is enabled.
  72. VGA The VGA console has been enabled.
  73. VT Virtual terminal support is enabled.
  74. WDT Watchdog support is enabled.
  75. XT IBM PC/XT MFM hard disk support is enabled.
  76. X86-64 X86-64 architecture is enabled.
  77. More X86-64 boot options can be found in
  78. Documentation/x86_64/boot-options.txt .
  79. In addition, the following text indicates that the option:
  80. BUGS= Relates to possible processor bugs on the said processor.
  81. KNL Is a kernel start-up parameter.
  82. BOOT Is a boot loader parameter.
  83. Parameters denoted with BOOT are actually interpreted by the boot
  84. loader, and have no meaning to the kernel directly.
  85. Do not modify the syntax of boot loader parameters without extreme
  86. need or coordination with <Documentation/i386/boot.txt>.
  87. Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
  88. a trailing = on the name of any parameter states that that parameter will
  89. be entered as an environment variable, whereas its absence indicates that
  90. it will appear as a kernel argument readable via /proc/cmdline by programs
  91. running once the system is up.
  92. 53c7xx= [HW,SCSI] Amiga SCSI controllers
  93. See header of drivers/scsi/53c7xx.c.
  94. See also Documentation/scsi/ncr53c7xx.txt.
  95. acpi= [HW,ACPI] Advanced Configuration and Power Interface
  96. Format: { force | off | ht | strict }
  97. force -- enable ACPI if default was off
  98. off -- disable ACPI if default was on
  99. noirq -- do not use ACPI for IRQ routing
  100. ht -- run only enough ACPI to enable Hyper Threading
  101. strict -- Be less tolerant of platforms that are not
  102. strictly ACPI specification compliant.
  103. See also Documentation/pm.txt, pci=noacpi
  104. acpi_sleep= [HW,ACPI] Sleep options
  105. Format: { s3_bios, s3_mode }
  106. See Documentation/power/video.txt
  107. acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
  108. Format: { level | edge | high | low }
  109. acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs
  110. default in APIC mode
  111. acpi_irq_nobalance [HW,ACPI] ACPI will not move active IRQs (default)
  112. default in PIC mode
  113. acpi_irq_pci= [HW,ACPI] If irq_balance, Clear listed IRQs for use by PCI
  114. Format: <irq>,<irq>...
  115. acpi_irq_isa= [HW,ACPI] If irq_balance, Mark listed IRQs used by ISA
  116. Format: <irq>,<irq>...
  117. acpi_osi= [HW,ACPI] empty param disables _OSI
  118. acpi_serialize [HW,ACPI] force serialization of AML methods
  119. acpi_skip_timer_override [HW,ACPI]
  120. Recognize and ignore IRQ0/pin2 Interrupt Override.
  121. For broken nForce2 BIOS resulting in XT-PIC timer.
  122. acpi_dbg_layer= [HW,ACPI]
  123. Format: <int>
  124. Each bit of the <int> indicates an acpi debug layer,
  125. 1: enable, 0: disable. It is useful for boot time
  126. debugging. After system has booted up, it can be set
  127. via /proc/acpi/debug_layer.
  128. acpi_dbg_level= [HW,ACPI]
  129. Format: <int>
  130. Each bit of the <int> indicates an acpi debug level,
  131. 1: enable, 0: disable. It is useful for boot time
  132. debugging. After system has booted up, it can be set
  133. via /proc/acpi/debug_level.
  134. acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
  135. ad1816= [HW,OSS]
  136. Format: <io>,<irq>,<dma>,<dma2>
  137. See also Documentation/sound/oss/AD1816.
  138. ad1848= [HW,OSS]
  139. Format: <io>,<irq>,<dma>,<dma2>,<type>
  140. adlib= [HW,OSS]
  141. Format: <io>
  142. advansys= [HW,SCSI]
  143. See header of drivers/scsi/advansys.c.
  144. advwdt= [HW,WDT] Advantech WDT
  145. Format: <iostart>,<iostop>
  146. aedsp16= [HW,OSS] Audio Excel DSP 16
  147. Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
  148. See also header of sound/oss/aedsp16.c.
  149. aha152x= [HW,SCSI]
  150. See Documentation/scsi/aha152x.txt.
  151. aha1542= [HW,SCSI]
  152. Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
  153. aic7xxx= [HW,SCSI]
  154. See Documentation/scsi/aic7xxx.txt.
  155. aic79xx= [HW,SCSI]
  156. See Documentation/scsi/aic79xx.txt.
  157. AM53C974= [HW,SCSI]
  158. Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
  159. See also header of drivers/scsi/AM53C974.c.
  160. amijoy.map= [HW,JOY] Amiga joystick support
  161. Map of devices attached to JOY0DAT and JOY1DAT
  162. Format: <a>,<b>
  163. See also Documentation/kernel/input/joystick.txt
  164. analog.map= [HW,JOY] Analog joystick and gamepad support
  165. Specifies type or capabilities of an analog joystick
  166. connected to one of 16 gameports
  167. Format: <type1>,<type2>,..<type16>
  168. apc= [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.)
  169. Format: noidle
  170. Disable APC CPU standby support. SPARCstation-Fox does
  171. not play well with APC CPU idle - disable it if you have
  172. APC and your system crashes randomly.
  173. apic= [APIC,i386] Change the output verbosity whilst booting
  174. Format: { quiet (default) | verbose | debug }
  175. Change the amount of debugging information output
  176. when initialising the APIC and IO-APIC components.
  177. apm= [APM] Advanced Power Management
  178. See header of arch/i386/kernel/apm.c.
  179. applicom= [HW]
  180. Format: <mem>,<irq>
  181. arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
  182. Format: <io>,<irq>,<nodeID>
  183. ataflop= [HW,M68k]
  184. atarimouse= [HW,MOUSE] Atari Mouse
  185. atascsi= [HW,SCSI] Atari SCSI
  186. atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
  187. EzKey and similar keyboards
  188. atkbd.reset= [HW] Reset keyboard during initialization
  189. atkbd.set= [HW] Select keyboard code set
  190. Format: <int> (2 = AT (default) 3 = PS/2)
  191. atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
  192. keyboards
  193. atkbd.softraw= [HW] Choose between synthetic and real raw mode
  194. Format: <bool> (0 = real, 1 = synthetic (default))
  195. atkbd.softrepeat=
  196. [HW] Use software keyboard repeat
  197. autotest [IA64]
  198. awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
  199. Format: <io>,<memsize>,<isapnp>
  200. aztcd= [HW,CD] Aztech CD268 CDROM driver
  201. Format: <io>,0x79 (?)
  202. baycom_epp= [HW,AX25]
  203. Format: <io>,<mode>
  204. baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
  205. Format: <io>,<mode>
  206. See header of drivers/net/hamradio/baycom_par.c.
  207. baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode)
  208. Format: <io>,<irq>,<mode>[,<baud>]
  209. See header of drivers/net/hamradio/baycom_ser_fdx.c.
  210. baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode)
  211. Format: <io>,<irq>,<mode>
  212. See header of drivers/net/hamradio/baycom_ser_hdx.c.
  213. blkmtd_device= [HW,MTD]
  214. blkmtd_erasesz=
  215. blkmtd_ro=
  216. blkmtd_bs=
  217. blkmtd_count=
  218. bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
  219. bttv.radio= Most important insmod options are available as kernel args too.
  220. bttv.pll= See Documentation/video4linux/bttv/Insmod-options
  221. bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
  222. BusLogic= [HW,SCSI]
  223. See drivers/scsi/BusLogic.c, comment before function
  224. BusLogic_ParseDriverOptions().
  225. c101= [NET] Moxa C101 synchronous serial card
  226. cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
  227. Sometimes CPU hardware bugs make them report the cache
  228. size incorrectly. The kernel will attempt work arounds
  229. to fix known problems, but for some CPUs it is not
  230. possible to determine what the correct size should be.
  231. This option provides an override for these situations.
  232. cdu31a= [HW,CD]
  233. Format: <io>,<irq>[,PAS]
  234. See header of drivers/cdrom/cdu31a.c.
  235. chandev= [HW,NET] Generic channel device initialisation
  236. checkreqprot [SELINUX] Set initial checkreqprot flag value.
  237. Format: { "0" | "1" }
  238. See security/selinux/Kconfig help text.
  239. 0 -- check protection applied by kernel (includes any implied execute protection).
  240. 1 -- check protection requested by application.
  241. Default value is set via a kernel config option.
  242. Value can be changed at runtime via /selinux/checkreqprot.
  243. clock= [BUGS=IA-32, HW] gettimeofday timesource override.
  244. Forces specified timesource (if avaliable) to be used
  245. when calculating gettimeofday(). If specicified timesource
  246. is not avalible, it defaults to PIT.
  247. Format: { pit | tsc | cyclone | pmtmr }
  248. hpet= [IA-32,HPET] option to disable HPET and use PIT.
  249. Format: disable
  250. cm206= [HW,CD]
  251. Format: { auto | [<io>,][<irq>] }
  252. com20020= [HW,NET] ARCnet - COM20020 chipset
  253. Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
  254. com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
  255. Format: <io>[,<irq>]
  256. com90xx= [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers)
  257. Format: <io>[,<irq>[,<memstart>]]
  258. condev= [HW,S390] console device
  259. conmode=
  260. console= [KNL] Output console device and options.
  261. tty<n> Use the virtual console device <n>.
  262. ttyS<n>[,options]
  263. Use the specified serial port. The options are of
  264. the form "bbbbpn", where "bbbb" is the baud rate,
  265. "p" is parity ("n", "o", or "e"), and "n" is bits.
  266. Default is "9600n8".
  267. See also Documentation/serial-console.txt.
  268. uart,io,<addr>[,options]
  269. uart,mmio,<addr>[,options]
  270. Start an early, polled-mode console on the 8250/16550
  271. UART at the specified I/O port or MMIO address,
  272. switching to the matching ttyS device later. The
  273. options are the same as for ttyS, above.
  274. cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
  275. Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
  276. cpia_pp= [HW,PPT]
  277. Format: { parport<nr> | auto | none }
  278. cs4232= [HW,OSS]
  279. Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
  280. cs89x0_dma= [HW,NET]
  281. Format: <dma>
  282. cs89x0_media= [HW,NET]
  283. Format: { rj45 | aui | bnc }
  284. cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
  285. dasd= [HW,NET]
  286. See header of drivers/s390/block/dasd_devmap.c.
  287. db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
  288. (one device per port)
  289. Format: <port#>,<type>
  290. See also Documentation/input/joystick-parport.txt
  291. debug [KNL] Enable kernel debugging (events log level).
  292. decnet= [HW,NET]
  293. Format: <area>[,<node>]
  294. See also Documentation/networking/decnet.txt.
  295. devfs= [DEVFS]
  296. See Documentation/filesystems/devfs/boot-options.
  297. dhash_entries= [KNL]
  298. Set number of hash buckets for dentry cache.
  299. digi= [HW,SERIAL]
  300. IO parameters + enable/disable command.
  301. digiepca= [HW,SERIAL]
  302. See drivers/char/README.epca and
  303. Documentation/digiepca.txt.
  304. dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
  305. support available.
  306. Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
  307. dmasound= [HW,OSS] Sound subsystem buffers
  308. dscc4.setup= [NET]
  309. dtc3181e= [HW,SCSI]
  310. earlyprintk= [IA-32, X86-64]
  311. earlyprintk=vga
  312. earlyprintk=serial[,ttySn[,baudrate]]
  313. Append ,keep to not disable it when the real console
  314. takes over.
  315. Only vga or serial at a time, not both.
  316. Currently only ttyS0 and ttyS1 are supported.
  317. Interaction with the standard serial driver is not
  318. very good.
  319. The VGA output is eventually overwritten by the real
  320. console.
  321. eata= [HW,SCSI]
  322. eda= [HW,PS2]
  323. edb= [HW,PS2]
  324. edd= [EDD]
  325. Format: {"of[f]" | "sk[ipmbr]"}
  326. See comment in arch/i386/boot/edd.S
  327. eicon= [HW,ISDN]
  328. Format: <id>,<membase>,<irq>
  329. eisa_irq_edge= [PARISC,HW]
  330. See header of drivers/parisc/eisa.c.
  331. elanfreq= [IA-32]
  332. See comment before function elanfreq_setup() in
  333. arch/i386/kernel/cpu/cpufreq/elanfreq.c.
  334. elevator= [IOSCHED]
  335. Format: {"as"|"cfq"|"deadline"|"noop"}
  336. See Documentation/block/as-iosched.txt
  337. and Documentation/block/deadline-iosched.txt for details.
  338. enforcing [SELINUX] Set initial enforcing status.
  339. Format: {"0" | "1"}
  340. See security/selinux/Kconfig help text.
  341. 0 -- permissive (log only, no denials).
  342. 1 -- enforcing (deny and log).
  343. Default value is 0.
  344. Value can be changed at runtime via /selinux/enforce.
  345. es1370= [HW,OSS]
  346. Format: <lineout>[,<micbias>]
  347. See also header of sound/oss/es1370.c.
  348. es1371= [HW,OSS]
  349. Format: <spdif>,[<nomix>,[<amplifier>]]
  350. See also header of sound/oss/es1371.c.
  351. ether= [HW,NET] Ethernet cards parameters
  352. This option is obsoleted by the "netdev=" option, which
  353. has equivalent usage. See its documentation for details.
  354. eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
  355. Format: <io>[,<irq>]
  356. fd_mcs= [HW,SCSI]
  357. See header of drivers/scsi/fd_mcs.c.
  358. fdomain= [HW,SCSI]
  359. See header of drivers/scsi/fdomain.c.
  360. floppy= [HW]
  361. See Documentation/floppy.txt.
  362. ftape= [HW] Floppy Tape subsystem debugging options.
  363. See Documentation/ftape.txt.
  364. gamecon.map[2|3]=
  365. [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
  366. support via parallel port (up to 5 devices per port)
  367. Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
  368. See also Documentation/input/joystick-parport.txt
  369. gamma= [HW,DRM]
  370. gdth= [HW,SCSI]
  371. See header of drivers/scsi/gdth.c.
  372. gpt [EFI] Forces disk with valid GPT signature but
  373. invalid Protective MBR to be treated as GPT.
  374. gscd= [HW,CD]
  375. Format: <io>
  376. gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
  377. gus= [HW,OSS]
  378. Format: <io>,<irq>,<dma>,<dma16>
  379. gvp11= [HW,SCSI]
  380. hashdist= [KNL,NUMA] Large hashes allocated during boot
  381. are distributed across NUMA nodes. Defaults on
  382. for IA-64, off otherwise.
  383. hcl= [IA-64] SGI's Hardware Graph compatibility layer
  384. hd= [EIDE] (E)IDE hard drive subsystem geometry
  385. Format: <cyl>,<head>,<sect>
  386. hd?= [HW] (E)IDE subsystem
  387. hd?lun= See Documentation/ide.txt.
  388. highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
  389. size of <nn>. This works even on boxes that have no
  390. highmem otherwise. This also works to reduce highmem
  391. size on bigger boxes.
  392. hisax= [HW,ISDN]
  393. See Documentation/isdn/README.HiSax.
  394. hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
  395. noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
  396. i8042.direct [HW] Put keyboard port into non-translated mode
  397. i8042.dumbkbd [HW] Pretend that controlled can only read data from
  398. keyboard and can not control its state
  399. (Don't attempt to blink the leds)
  400. i8042.noaux [HW] Don't check for auxiliary (== mouse) port
  401. i8042.nomux [HW] Don't check presence of an active multiplexing
  402. controller
  403. i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
  404. controllers
  405. i8042.panicblink=
  406. [HW] Frequency with which keyboard LEDs should blink
  407. when kernel panics (default is 0.5 sec)
  408. i8042.reset [HW] Reset the controller during init and cleanup
  409. i8042.unlock [HW] Unlock (ignore) the keylock
  410. i810= [HW,DRM]
  411. i8k.force [HW] Activate i8k driver even if SMM BIOS signature
  412. does not match list of supported models.
  413. i8k.power_status
  414. [HW] Report power status in /proc/i8k
  415. (disabled by default)
  416. i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
  417. capability is set.
  418. ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
  419. See Documentation/mca.txt.
  420. icn= [HW,ISDN]
  421. Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
  422. ide= [HW] (E)IDE subsystem
  423. Format: ide=nodma or ide=doubler or ide=reverse
  424. See Documentation/ide.txt.
  425. ide?= [HW] (E)IDE subsystem
  426. Format: ide?=noprobe or chipset specific parameters.
  427. See Documentation/ide.txt.
  428. idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
  429. See Documentation/ide.txt.
  430. idle= [HW]
  431. Format: idle=poll or idle=halt
  432. ihash_entries= [KNL]
  433. Set number of hash buckets for inode cache.
  434. in2000= [HW,SCSI]
  435. See header of drivers/scsi/in2000.c.
  436. init= [KNL]
  437. Format: <full_path>
  438. Run specified binary instead of /sbin/init as init
  439. process.
  440. initcall_debug [KNL] Trace initcalls as they are executed. Useful
  441. for working out where the kernel is dying during
  442. startup.
  443. initrd= [BOOT] Specify the location of the initial ramdisk
  444. inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
  445. Format: <irq>
  446. inttest= [IA64]
  447. io7= [HW] IO7 for Marvel based alpha systems
  448. See comment before marvel_specify_io7 in
  449. arch/alpha/kernel/core_marvel.c.
  450. ip= [IP_PNP]
  451. See Documentation/nfsroot.txt.
  452. ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
  453. See comment before ip2_setup() in drivers/char/ip2.c.
  454. ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
  455. See header of drivers/scsi/ips.c.
  456. isapnp= [ISAPNP]
  457. Format: <RDP>, <reset>, <pci_scan>, <verbosity>
  458. isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
  459. Format: <cpu number>,...,<cpu number>
  460. This option can be used to specify one or more CPUs
  461. to isolate from the general SMP balancing and scheduling
  462. algorithms. The only way to move a process onto or off
  463. an "isolated" CPU is via the CPU affinity syscalls.
  464. <cpu number> begins at 0 and the maximum value is
  465. "number of CPUs in system - 1".
  466. This option is the preferred way to isolate CPUs. The
  467. alternative - manually setting the CPU mask of all tasks
  468. in the system can cause problems and suboptimal load
  469. balancer performance.
  470. isp16= [HW,CD]
  471. Format: <io>,<irq>,<dma>,<setup>
  472. iucv= [HW,NET]
  473. js= [HW,JOY] Analog joystick
  474. See Documentation/input/joystick.txt.
  475. keepinitrd [HW,ARM]
  476. kstack=N [IA-32, X86-64] Print N words from the kernel stack
  477. in oops dumps.
  478. l2cr= [PPC]
  479. lapic [IA-32,APIC] Enable the local APIC even if BIOS disabled it.
  480. lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
  481. Format: addr:<io>,irq:<irq>
  482. llsc*= [IA64]
  483. See function print_params() in arch/ia64/sn/kernel/llsc4.c.
  484. load_ramdisk= [RAM] List of ramdisks to load from floppy
  485. See Documentation/ramdisk.txt.
  486. lockd.udpport= [NFS]
  487. lockd.tcpport= [NFS]
  488. logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
  489. Format: <irq>
  490. loglevel= All Kernel Messages with a loglevel smaller than the
  491. console loglevel will be printed to the console. It can
  492. also be changed with klogd or other programs. The
  493. loglevels are defined as follows:
  494. 0 (KERN_EMERG) system is unusable
  495. 1 (KERN_ALERT) action must be taken immediately
  496. 2 (KERN_CRIT) critical conditions
  497. 3 (KERN_ERR) error conditions
  498. 4 (KERN_WARNING) warning conditions
  499. 5 (KERN_NOTICE) normal but significant condition
  500. 6 (KERN_INFO) informational
  501. 7 (KERN_DEBUG) debug-level messages
  502. log_buf_len=n Sets the size of the printk ring buffer, in bytes.
  503. Format is n, nk, nM. n must be a power of two. The
  504. default is set in kernel config.
  505. lp=0 [LP] Specify parallel ports to use, e.g,
  506. lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
  507. lp=reset first parallel port). 'lp=0' disables the
  508. lp=auto printer driver. 'lp=reset' (which can be
  509. specified in addition to the ports) causes
  510. attached printers to be reset. Using
  511. lp=port1,port2,... specifies the parallel ports
  512. to associate lp devices with, starting with
  513. lp0. A port specification may be 'none' to skip
  514. that lp device, or a parport name such as
  515. 'parport0'. Specifying 'lp=auto' instead of a
  516. port specification list means that device IDs
  517. from each port should be examined, to see if
  518. an IEEE 1284-compliant printer is attached; if
  519. so, the driver will manage that printer.
  520. See also header of drivers/char/lp.c.
  521. lpj=n [KNL]
  522. Sets loops_per_jiffy to given constant, thus avoiding
  523. time-consuming boot-time autodetection (up to 250 ms per
  524. CPU). 0 enables autodetection (default). To determine
  525. the correct value for your kernel, boot with normal
  526. autodetection and see what value is printed. Note that
  527. on SMP systems the preset will be applied to all CPUs,
  528. which is likely to cause problems if your CPUs need
  529. significantly divergent settings. An incorrect value
  530. will cause delays in the kernel to be wrong, leading to
  531. unpredictable I/O errors and other breakage. Although
  532. unlikely, in the extreme case this might damage your
  533. hardware.
  534. ltpc= [NET]
  535. Format: <io>,<irq>,<dma>
  536. mac5380= [HW,SCSI]
  537. Format: <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
  538. mac53c9x= [HW,SCSI]
  539. Format: <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
  540. machvec= [IA64]
  541. Force the use of a particular machine-vector (machvec) in a generic
  542. kernel. Example: machvec=hpzx1_swiotlb
  543. mad16= [HW,OSS]
  544. Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
  545. maui= [HW,OSS]
  546. Format: <io>,<irq>
  547. max_loop= [LOOP] Maximum number of loopback devices that can
  548. be mounted
  549. Format: <1-256>
  550. maxcpus= [SMP] Maximum number of processors that an SMP kernel
  551. should make use of
  552. max_luns= [SCSI] Maximum number of LUNs to probe
  553. Should be between 1 and 2^32-1.
  554. max_report_luns=
  555. [SCSI] Maximum number of LUNs received
  556. Should be between 1 and 16384.
  557. mca-pentium [BUGS=IA-32]
  558. mcatest= [IA-64]
  559. mcd= [HW,CD]
  560. Format: <port>,<irq>,<mitsumi_bug_93_wait>
  561. mcdx= [HW,CD]
  562. mce [IA-32] Machine Check Exception
  563. md= [HW] RAID subsystems devices and level
  564. See Documentation/md.txt.
  565. mdacon= [MDA]
  566. Format: <first>,<last>
  567. Specifies range of consoles to be captured by the MDA.
  568. mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
  569. Amount of memory to be used when the kernel is not able
  570. to see the whole system memory or for test.
  571. [IA-32] Use together with memmap= to avoid physical
  572. address space collisions. Without memmap= PCI devices
  573. could be placed at addresses belonging to unused RAM.
  574. mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
  575. memory.
  576. memmap=exactmap [KNL,IA-32] Enable setting of an exact
  577. E820 memory map, as specified by the user.
  578. Such memmap=exactmap lines can be constructed based on
  579. BIOS output or other requirements. See the memmap=nn@ss
  580. option description.
  581. memmap=nn[KMG]@ss[KMG]
  582. [KNL] Force usage of a specific region of memory
  583. Region of memory to be used, from ss to ss+nn.
  584. memmap=nn[KMG]#ss[KMG]
  585. [KNL,ACPI] Mark specific memory as ACPI data.
  586. Region of memory to be used, from ss to ss+nn.
  587. memmap=nn[KMG]$ss[KMG]
  588. [KNL,ACPI] Mark specific memory as reserved.
  589. Region of memory to be used, from ss to ss+nn.
  590. meye.*= [HW] Set MotionEye Camera parameters
  591. See Documentation/video4linux/meye.txt.
  592. mga= [HW,DRM]
  593. mousedev.tap_time=
  594. [MOUSE] Maximum time between finger touching and
  595. leaving touchpad surface for touch to be considered
  596. a tap and be reported as a left button click (for
  597. touchpads working in absolute mode only).
  598. Format: <msecs>
  599. mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
  600. reporting absolute coordinates, such as tablets
  601. mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
  602. reporting absolute coordinates, such as tablets
  603. mpu401= [HW,OSS]
  604. Format: <io>,<irq>
  605. MTD_Partition= [MTD]
  606. Format: <name>,<region-number>,<size>,<offset>
  607. MTD_Region= [MTD]
  608. Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
  609. mtdparts= [MTD]
  610. See drivers/mtd/cmdline.c.
  611. mtouchusb.raw_coordinates=
  612. [HW] Make the MicroTouch USB driver use raw coordinates ('y', default)
  613. or cooked coordinates ('n')
  614. n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
  615. NCR_D700= [HW,SCSI]
  616. See header of drivers/scsi/NCR_D700.c.
  617. ncr5380= [HW,SCSI]
  618. ncr53c400= [HW,SCSI]
  619. ncr53c400a= [HW,SCSI]
  620. ncr53c406a= [HW,SCSI]
  621. ncr53c8xx= [HW,SCSI]
  622. netdev= [NET] Network devices parameters
  623. Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
  624. Note that mem_start is often overloaded to mean
  625. something different and driver-specific.
  626. nfsaddrs= [NFS]
  627. See Documentation/nfsroot.txt.
  628. nfsroot= [NFS] nfs root filesystem for disk-less boxes.
  629. See Documentation/nfsroot.txt.
  630. nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
  631. no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
  632. emulation library even if a 387 maths coprocessor
  633. is present.
  634. noalign [KNL,ARM]
  635. noapic [SMP,APIC] Tells the kernel to not make use of any
  636. IOAPICs that may be present in the system.
  637. noasync [HW,M68K] Disables async and sync negotiation for
  638. all devices.
  639. nobats [PPC] Do not use BATs for mapping kernel lowmem
  640. on "Classic" PPC cores.
  641. nocache [ARM]
  642. nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
  643. noexec [IA-64]
  644. noexec [IA-32, X86-64]
  645. noexec=on: enable non-executable mappings (default)
  646. noexec=off: disable nn-executable mappings
  647. nofxsr [BUGS=IA-32]
  648. nohlt [BUGS=ARM]
  649. no-hlt [BUGS=IA-32] Tells the kernel that the hlt
  650. instruction doesn't work correctly and not to
  651. use it.
  652. nohalt [IA-64] Tells the kernel not to use the power saving
  653. function PAL_HALT_LIGHT when idle. This increases
  654. power-consumption. On the positive side, it reduces
  655. interrupt wake-up latency, which may improve performance
  656. in certain environments such as networked servers or
  657. real-time systems.
  658. noirqdebug [IA-32] Disables the code which attempts to detect and
  659. disable unhandled interrupt sources.
  660. noisapnp [ISAPNP] Disables ISA PnP code.
  661. noinitrd [RAM] Tells the kernel not to load any configured
  662. initial RAM disk.
  663. nointroute [IA-64]
  664. nolapic [IA-32,APIC] Do not enable or use the local APIC.
  665. noltlbs [PPC] Do not use large page/tlb entries for kernel
  666. lowmem mapping on PPC40x.
  667. nomce [IA-32] Machine Check Exception
  668. noresidual [PPC] Don't use residual data on PReP machines.
  669. noresume [SWSUSP] Disables resume and restore original swap space.
  670. no-scroll [VGA] Disables scrollback.
  671. This is required for the Braillex ib80-piezo Braille
  672. reader made by F.H. Papenmeier (Germany).
  673. nosbagart [IA-64]
  674. nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
  675. nosync [HW,M68K] Disables sync negotiation for all devices.
  676. notsc [BUGS=IA-32] Disable Time Stamp Counter
  677. nousb [USB] Disable the USB subsystem
  678. nowb [ARM]
  679. opl3= [HW,OSS]
  680. Format: <io>
  681. opl3sa= [HW,OSS]
  682. Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
  683. opl3sa2= [HW,OSS]
  684. Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
  685. oprofile.timer= [HW]
  686. Use timer interrupt instead of performance counters
  687. optcd= [HW,CD]
  688. Format: <io>
  689. osst= [HW,SCSI] SCSI Tape Driver
  690. Format: <buffer_size>,<write_threshold>
  691. See also Documentation/scsi/st.txt.
  692. panic= [KNL] Kernel behaviour on panic
  693. Format: <timeout>
  694. parkbd.port= [HW] Parallel port number the keyboard adapter is
  695. connected to, default is 0.
  696. Format: <parport#>
  697. parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
  698. 0 for XT, 1 for AT (default is AT).
  699. Format: <mode>
  700. parport=0 [HW,PPT] Specify parallel ports. 0 disables.
  701. parport=auto Use 'auto' to force the driver to use
  702. parport=0xBBB[,IRQ[,DMA]] any IRQ/DMA settings detected (the
  703. default is to ignore detected IRQ/DMA
  704. settings because of possible
  705. conflicts). You can specify the base
  706. address, IRQ, and DMA settings; IRQ and
  707. DMA should be numbers, or 'auto' (for
  708. using detected settings on that
  709. particular port), or 'nofifo' (to avoid
  710. using a FIFO even if it is detected).
  711. Parallel ports are assigned in the
  712. order they are specified on the command
  713. line, starting with parport0.
  714. parport_init_mode=
  715. [HW,PPT] Configure VIA parallel port to
  716. operate in specific mode. This is
  717. necessary on Pegasos computer where
  718. firmware has no options for setting up
  719. parallel port mode and sets it to
  720. spp. Currently this function knows
  721. 686a and 8231 chips.
  722. Format: [spp|ps2|epp|ecp|ecpepp]
  723. pas2= [HW,OSS]
  724. Format: <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
  725. pas16= [HW,SCSI]
  726. See header of drivers/scsi/pas16.c.
  727. pcbit= [HW,ISDN]
  728. pcd. [PARIDE]
  729. See header of drivers/block/paride/pcd.c.
  730. See also Documentation/paride.txt.
  731. pci=option[,option...] [PCI] various PCI subsystem options:
  732. off [IA-32] don't probe for the PCI bus
  733. bios [IA-32] force use of PCI BIOS, don't access
  734. the hardware directly. Use this if your machine
  735. has a non-standard PCI host bridge.
  736. nobios [IA-32] disallow use of PCI BIOS, only direct
  737. hardware access methods are allowed. Use this
  738. if you experience crashes upon bootup and you
  739. suspect they are caused by the BIOS.
  740. conf1 [IA-32] Force use of PCI Configuration Mechanism 1.
  741. conf2 [IA-32] Force use of PCI Configuration Mechanism 2.
  742. nosort [IA-32] Don't sort PCI devices according to
  743. order given by the PCI BIOS. This sorting is done
  744. to get a device order compatible with older kernels.
  745. biosirq [IA-32] Use PCI BIOS calls to get the interrupt
  746. routing table. These calls are known to be buggy
  747. on several machines and they hang the machine when used,
  748. but on other computers it's the only way to get the
  749. interrupt routing table. Try this option if the kernel
  750. is unable to allocate IRQs or discover secondary PCI
  751. buses on your motherboard.
  752. rom [IA-32] Assign address space to expansion ROMs.
  753. Use with caution as certain devices share address
  754. decoders between ROMs and other resources.
  755. irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be assigned
  756. automatically to PCI devices. You can make the kernel
  757. exclude IRQs of your ISA cards this way.
  758. lastbus=N [IA-32] Scan all buses till bus #N. Can be useful
  759. if the kernel is unable to find your secondary buses
  760. and you want to tell it explicitly which ones they are.
  761. assign-busses [IA-32] Always assign all PCI bus
  762. numbers ourselves, overriding
  763. whatever the firmware may have
  764. done.
  765. usepirqmask [IA-32] Honor the possible IRQ mask
  766. stored in the BIOS $PIR table. This is
  767. needed on some systems with broken
  768. BIOSes, notably some HP Pavilion N5400
  769. and Omnibook XE3 notebooks. This will
  770. have no effect if ACPI IRQ routing is
  771. enabled.
  772. noacpi [IA-32] Do not use ACPI for IRQ routing
  773. or for PCI scanning.
  774. routeirq Do IRQ routing for all PCI devices.
  775. This is normally done in pci_enable_device(),
  776. so this option is a temporary workaround
  777. for broken drivers that don't call it.
  778. firmware [ARM] Do not re-enumerate the bus but
  779. instead just use the configuration
  780. from the bootloader. This is currently
  781. used on IXP2000 systems where the
  782. bus has to be configured a certain way
  783. for adjunct CPUs.
  784. pcmv= [HW,PCMCIA] BadgePAD 4
  785. pd. [PARIDE]
  786. See Documentation/paride.txt.
  787. pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
  788. boot time.
  789. Format: { 0 | 1 }
  790. See arch/parisc/kernel/pdc_chassis.c
  791. pf. [PARIDE]
  792. See Documentation/paride.txt.
  793. pg. [PARIDE]
  794. See Documentation/paride.txt.
  795. pirq= [SMP,APIC] Manual mp-table setup
  796. See Documentation/i386/IO-APIC.txt.
  797. plip= [PPT,NET] Parallel port network link
  798. Format: { parport<nr> | timid | 0 }
  799. See also Documentation/parport.txt.
  800. pnpacpi= [ACPI]
  801. { off }
  802. pnpbios= [ISAPNP]
  803. { on | off | curr | res | no-curr | no-res }
  804. pnp_reserve_irq=
  805. [ISAPNP] Exclude IRQs for the autoconfiguration
  806. pnp_reserve_dma=
  807. [ISAPNP] Exclude DMAs for the autoconfiguration
  808. pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
  809. Ranges are in pairs (I/O port base and size).
  810. pnp_reserve_mem=
  811. [ISAPNP] Exclude memory regions for the autoconfiguration
  812. Ranges are in pairs (memory base and size).
  813. profile= [KNL] Enable kernel profiling via /proc/profile
  814. { schedule | <number> }
  815. (param: schedule - profile schedule points}
  816. (param: profile step/bucket size as a power of 2 for
  817. statistical time based profiling)
  818. processor.max_cstate= [HW, ACPI]
  819. Limit processor to maximum C-state
  820. max_cstate=9 overrides any DMI blacklist limit.
  821. prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
  822. before loading.
  823. See Documentation/ramdisk.txt.
  824. psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
  825. probe for (bare|imps|exps).
  826. psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
  827. per second.
  828. psmouse.resetafter=
  829. [HW,MOUSE] Try to reset the device after so many bad packets
  830. (0 = never).
  831. psmouse.resolution=
  832. [HW,MOUSE] Set desired mouse resolution, in dpi.
  833. psmouse.smartscroll=
  834. [HW,MOUSE] Controls Logitech smartscroll autorepeat,
  835. 0 = disabled, 1 = enabled (default).
  836. pss= [HW,OSS] Personal Sound System (ECHO ESC614)
  837. Format: <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
  838. pt. [PARIDE]
  839. See Documentation/paride.txt.
  840. quiet= [KNL] Disable log messages
  841. r128= [HW,DRM]
  842. raid= [HW,RAID]
  843. See Documentation/md.txt.
  844. ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
  845. See Documentation/ramdisk.txt.
  846. ramdisk_blocksize=
  847. [RAM]
  848. See Documentation/ramdisk.txt.
  849. ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
  850. New name for the ramdisk parameter.
  851. See Documentation/ramdisk.txt.
  852. reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
  853. Format: <reboot_mode>[,<reboot_mode2>[,...]]
  854. See arch/*/kernel/reboot.c.
  855. reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
  856. resume= [SWSUSP] Specify the partition device for software suspension
  857. rhash_entries= [KNL,NET]
  858. Set number of hash buckets for route cache
  859. riscom8= [HW,SERIAL]
  860. Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
  861. ro [KNL] Mount root device read-only on boot
  862. root= [KNL] Root filesystem
  863. rootdelay= [KNL] Delay (in seconds) to pause before attempting to
  864. mount the root filesystem
  865. rootflags= [KNL] Set root filesystem mount option string
  866. rootfstype= [KNL] Set root filesystem type
  867. rw [KNL] Mount root device read-write on boot
  868. S [KNL] Run init in single mode
  869. sa1100ir [NET]
  870. See drivers/net/irda/sa1100_ir.c.
  871. sb= [HW,OSS]
  872. Format: <io>,<irq>,<dma>,<dma2>
  873. sbni= [NET] Granch SBNI12 leased line adapter
  874. sbpcd= [HW,CD] Soundblaster CD adapter
  875. Format: <io>,<type>
  876. See a comment before function sbpcd_setup() in
  877. drivers/cdrom/sbpcd.c.
  878. sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
  879. Format: <io>[,<timeout>[,<isapnp>]]
  880. scsi_debug_*= [SCSI]
  881. See drivers/scsi/scsi_debug.c.
  882. scsi_default_dev_flags=
  883. [SCSI] SCSI default device flags
  884. Format: <integer>
  885. scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
  886. Format: <vendor>:<model>:<flags>
  887. (flags are integer value)
  888. scsi_logging= [SCSI]
  889. selinux [SELINUX] Disable or enable SELinux at boot time.
  890. Format: { "0" | "1" }
  891. See security/selinux/Kconfig help text.
  892. 0 -- disable.
  893. 1 -- enable.
  894. Default value is set via kernel config option.
  895. If enabled at boot time, /selinux/disable can be used
  896. later to disable prior to initial policy load.
  897. serialnumber [BUGS=IA-32]
  898. sg_def_reserved_size=
  899. [SCSI]
  900. sgalaxy= [HW,OSS]
  901. Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
  902. shapers= [NET]
  903. Maximal number of shapers.
  904. sim710= [SCSI,HW]
  905. See header of drivers/scsi/sim710.c.
  906. simeth= [IA-64]
  907. simscsi=
  908. sjcd= [HW,CD]
  909. Format: <io>,<irq>,<dma>
  910. See header of drivers/cdrom/sjcd.c.
  911. slram= [HW,MTD]
  912. smart2= [HW]
  913. Format: <io1>[,<io2>[,...,<io8>]]
  914. snd-ad1816a= [HW,ALSA]
  915. snd-ad1848= [HW,ALSA]
  916. snd-ali5451= [HW,ALSA]
  917. snd-als100= [HW,ALSA]
  918. snd-als4000= [HW,ALSA]
  919. snd-azt2320= [HW,ALSA]
  920. snd-cmi8330= [HW,ALSA]
  921. snd-cmipci= [HW,ALSA]
  922. snd-cs4231= [HW,ALSA]
  923. snd-cs4232= [HW,ALSA]
  924. snd-cs4236= [HW,ALSA]
  925. snd-cs4281= [HW,ALSA]
  926. snd-cs46xx= [HW,ALSA]
  927. snd-dt019x= [HW,ALSA]
  928. snd-dummy= [HW,ALSA]
  929. snd-emu10k1= [HW,ALSA]
  930. snd-ens1370= [HW,ALSA]
  931. snd-ens1371= [HW,ALSA]
  932. snd-es968= [HW,ALSA]
  933. snd-es1688= [HW,ALSA]
  934. snd-es18xx= [HW,ALSA]
  935. snd-es1938= [HW,ALSA]
  936. snd-es1968= [HW,ALSA]
  937. snd-fm801= [HW,ALSA]
  938. snd-gusclassic= [HW,ALSA]
  939. snd-gusextreme= [HW,ALSA]
  940. snd-gusmax= [HW,ALSA]
  941. snd-hdsp= [HW,ALSA]
  942. snd-ice1712= [HW,ALSA]
  943. snd-intel8x0= [HW,ALSA]
  944. snd-interwave= [HW,ALSA]
  945. snd-interwave-stb=
  946. [HW,ALSA]
  947. snd-korg1212= [HW,ALSA]
  948. snd-maestro3= [HW,ALSA]
  949. snd-mpu401= [HW,ALSA]
  950. snd-mtpav= [HW,ALSA]
  951. snd-nm256= [HW,ALSA]
  952. snd-opl3sa2= [HW,ALSA]
  953. snd-opti92x-ad1848=
  954. [HW,ALSA]
  955. snd-opti92x-cs4231=
  956. [HW,ALSA]
  957. snd-opti93x= [HW,ALSA]
  958. snd-pmac= [HW,ALSA]
  959. snd-rme32= [HW,ALSA]
  960. snd-rme96= [HW,ALSA]
  961. snd-rme9652= [HW,ALSA]
  962. snd-sb8= [HW,ALSA]
  963. snd-sb16= [HW,ALSA]
  964. snd-sbawe= [HW,ALSA]
  965. snd-serial= [HW,ALSA]
  966. snd-sgalaxy= [HW,ALSA]
  967. snd-sonicvibes= [HW,ALSA]
  968. snd-sun-amd7930=
  969. [HW,ALSA]
  970. snd-sun-cs4231= [HW,ALSA]
  971. snd-trident= [HW,ALSA]
  972. snd-usb-audio= [HW,ALSA,USB]
  973. snd-via82xx= [HW,ALSA]
  974. snd-virmidi= [HW,ALSA]
  975. snd-wavefront= [HW,ALSA]
  976. snd-ymfpci= [HW,ALSA]
  977. sonicvibes= [HW,OSS]
  978. Format: <reverb>
  979. sonycd535= [HW,CD]
  980. Format: <io>[,<irq>]
  981. sonypi.*= [HW] Sony Programmable I/O Control Device driver
  982. See Documentation/sonypi.txt
  983. specialix= [HW,SERIAL] Specialix multi-serial port adapter
  984. See Documentation/specialix.txt.
  985. spia_io_base= [HW,MTD]
  986. spia_fio_base=
  987. spia_pedr=
  988. spia_peddr=
  989. sscape= [HW,OSS]
  990. Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
  991. st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
  992. See Documentation/scsi/st.txt.
  993. st0x= [HW,SCSI]
  994. See header of drivers/scsi/seagate.c.
  995. sti= [PARISC,HW]
  996. Format: <num>
  997. Set the STI (builtin display/keyboard on the HP-PARISC
  998. machines) console (graphic card) which should be used
  999. as the initial boot-console.
  1000. See also comment in drivers/video/console/sticore.c.
  1001. sti_font= [HW]
  1002. See comment in drivers/video/console/sticore.c.
  1003. stifb= [HW]
  1004. Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
  1005. stram_swap= [HW,M68k]
  1006. swiotlb= [IA-64] Number of I/O TLB slabs
  1007. switches= [HW,M68k]
  1008. sym53c416= [HW,SCSI]
  1009. See header of drivers/scsi/sym53c416.c.
  1010. t128= [HW,SCSI]
  1011. See header of drivers/scsi/t128.c.
  1012. tdfx= [HW,DRM]
  1013. thash_entries= [KNL,NET]
  1014. Set number of hash buckets for TCP connection
  1015. time Show timing data prefixed to each printk message line
  1016. tipar.timeout= [HW,PPT]
  1017. Set communications timeout in tenths of a second
  1018. (default 15).
  1019. tipar.delay= [HW,PPT]
  1020. Set inter-bit delay in microseconds (default 10).
  1021. tmc8xx= [HW,SCSI]
  1022. See header of drivers/scsi/seagate.c.
  1023. tmscsim= [HW,SCSI]
  1024. See comment before function dc390_setup() in
  1025. drivers/scsi/tmscsim.c.
  1026. tp720= [HW,PS2]
  1027. trix= [HW,OSS] MediaTrix AudioTrix Pro
  1028. Format: <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
  1029. tsdev.xres= [TS] Horizontal screen resolution.
  1030. tsdev.yres= [TS] Vertical screen resolution.
  1031. turbografx.map[2|3]=
  1032. [HW,JOY] TurboGraFX parallel port interface
  1033. Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
  1034. See also Documentation/input/joystick-parport.txt
  1035. u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
  1036. See header of drivers/scsi/u14-34f.c.
  1037. uart401= [HW,OSS]
  1038. Format: <io>,<irq>
  1039. uart6850= [HW,OSS]
  1040. Format: <io>,<irq>
  1041. usb-handoff [HW] Enable early USB BIOS -> OS handoff
  1042. usbhid.mousepoll=
  1043. [USBHID] The interval which mice are to be polled at.
  1044. video= [FB] Frame buffer configuration
  1045. See Documentation/fb/modedb.txt.
  1046. vga= [BOOT,IA-32] Select a particular video mode
  1047. See Documentation/i386/boot.txt and Documentation/svga.txt.
  1048. Use vga=ask for menu.
  1049. This is actually a boot loader parameter; the value is
  1050. passed to the kernel using a special protocol.
  1051. vmalloc=nn[KMG] [KNL,BOOT] forces the vmalloc area to have an exact
  1052. size of <nn>. This can be used to increase the
  1053. minimum size (128MB on x86). It can also be used to
  1054. decrease the size and leave more room for directly
  1055. mapped kernel RAM.
  1056. vmhalt= [KNL,S390]
  1057. vmpoff= [KNL,S390]
  1058. waveartist= [HW,OSS]
  1059. Format: <io>,<irq>,<dma>,<dma2>
  1060. wd33c93= [HW,SCSI]
  1061. See header of drivers/scsi/wd33c93.c.
  1062. wd7000= [HW,SCSI]
  1063. See header of drivers/scsi/wd7000.c.
  1064. wdt= [WDT] Watchdog
  1065. See Documentation/watchdog/watchdog.txt.
  1066. xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
  1067. xd_geo= See header of drivers/block/xd.c.
  1068. xirc2ps_cs= [NET,PCMCIA]
  1069. Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
  1070. Changelog:
  1071. The last known update (for 2.4.0) - the changelog was not kept before.
  1072. 2000-06-?? Mr. Unknown
  1073. Update for 2.5.49, description for most of the options introduced,
  1074. references to other documentation (C files, READMEs, ..), added S390,
  1075. PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
  1076. reformatting.
  1077. 2002-11-24 Petr Baudis <pasky@ucw.cz>
  1078. Randy Dunlap <randy.dunlap@verizon.net>
  1079. TODO:
  1080. Add documentation for ALSA options.
  1081. Add more DRM drivers.