June 1999 Kernel Parameters v2.2.9 ~~~~~~~~~~~~~~~~~ The following is a consolidated list of the kernel parameters as defined in the file init/main.c and sorted into English Dictionary order (defined as ignoring all punctuation and sorting digits before letters in a case insensitive manner), and with descriptions where known. The text in square brackets at the beginning of the description state the restrictions on the kernel for the said kernel parameter to be valid. The restrictions referred to are that the relevant option is valid if: APIC APIC support is enabled. APM Automatic Power Management support is enabled. AX25 Appropriate AX.25 support is enabled. CD Appropriate CD support is enabled. EIDE EIDE/ATAPI support is enabled. FB The frame buffer device is enabled. HW Appropriate hardware is enabled. ISDN Appropriate ISDN support is enabled. JOY Appropriate joystick support is enabled. LP Printer support is enabled. MCA MCA bus support is enabled. MDA The MDA console is enabled. MOUSE Appropriate mouse support is enabled. NET Appropriate network support is enabled. NFS Appropriate NFS support is enabled. PARIDE The ParIDE subsystem is enabled. PCI PCI bus support is enabled. PCMCIA The PCMCIA subsystem is enabled. PNP Plug & Play support is enabled. PPT Parallel port support is enabled. PS2 Appropriate PS/2 support is enabled. RAM RAMdisc support is enabled. SCSI Appropriate SCSI support is enabled. SERIAL Serial support is enabled. SMP The kernel is an SMP kernel. SOUND Appropriate sound system support is enabled. VGA The VGA console has been enabled. VT Virtual terminal support is enabled. XT IBM PC/XT MFM hard disk support is enabled. In addition, the following text indicates that the option: BUGS= Relates to possible processor bugs on the said processor. KNL Is a kernel start-up parameter. Note that ALL kernel parameters listed below are CASE SENSITIVE, and that a trailing = on the name of any parameter states that that parameter will be entered as an environment variable, whereas its absence indicates that it will appear as a kernel argument readable via /proc/cmdline by programs running once the system is up. 53c7xx= [HW,SCSI] adb_buttons= [HW,MOUSE] advansys= [HW,SCSI] aha152x= [HW,SCSI] aha1542= [HW,SCSI] aic7xxx= [HW,SCSI] AM53C974= [HW,SCSI] apm= [APM] Automatic Power Management. arcrimi= [HW,NET] atamouse= [HW,MOUSE] Atari Mouse. atascsi= [HW,SCSI] Atari SCSI. aztcd= [HW,CD] Aztec CD driver. baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem. baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem in Full Duplex Mode. baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem in Half Duplex Mode. bmouse= [HW,MOUSE,PS2] Bus mouse. BusLogic= [HW,SCSI] cdu31a= [HW,CD] cm206= [HW,CD] com20020= [HW,NET] com90io= [HW,NET] com90xx= [HW,NET] console= cyclades= [HW,SERIAL] Cyclades multi-serial port adapter. debug [KNL] Enable kernel debugging. decnet= [HW,NET] digi= [HW,SERIAL] digiepca= [HW,SERIAL] dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA support available. dmasound= [HW,SOUND] dtc3181e= [HW,SCSI] eata= [HW,SCSI] eda= [HW,PS2] edb= [HW,PS2] ether= [HW,NET] Ethernet. fd_mcs= [HW,SCSI] fdomain= [HW,SCSI] floppy= [HW] ftape= [HW] Floppy Tape subsystem. gdth= [HW,SCSI] gscd= [HW,CD] gvp11= [HW,SCSI] hd= [EIDE] IDE and EIDE hard drive subsystem. hfmodem= [HW,AX25] HiSax= [HW,ISDN] hisax= [HW,ISDN] ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter. icn= [HW,ISDN] in2000= [HW,SCSI] init= [KNL] ip= [PNP] isp16= [HW,CD] js_14= [HW,JOY] js_am= [HW,JOY] js_an= [HW,JOY] js_as= [HW.JOY] js_console= [HW,JOY] js_console2= [HW,JOY] js_console3= [HW,JOY] js_db9= [HW,JOY] js_db9_2= [HW,JOY] js_db9_3= [HW,JOY] js_tg= [HW,JOY] js_tg_2= [HW,JOY] js_tg_3= [HW,JOY] kbd-reset [VT] load_ramdisk= [RAM] lp=0 [LP] Specify parallel ports to use, e.g, or lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses or lp=reset first parallel port). 'lp=0' disables the printer or lp=auto driver. 'lp=reset' (which can be specified in addition to the ports) causes attached printers to be reset. Using lp=port1,port2,... specifies the parallel ports to associate lp devices with, starting with lp0. A port specification may be 'none' to skip that lp device, or a parport name such as 'parport0'. Specifying 'lp=auto' instead of a port specification list means that device IDs from each port should be examined, to see if an IEEE 1284-compliant printer is attached; if so, the driver will manage that printer. ltpc= [HW] mac5380= [HW,SCSI] maxcpus= [SMP] States the maximum number of processors that an SMP kernel should make use of. max_scsi_luns= [SCSI] mca-pentium [BUGS=ix86] mcd= [HW,CD] mcdx= [HW,CD] md= [HW] mdacon= [MDA] msmouse= [HW,MOUSE] Microsoft Mouse. ncr5380= [HW,SCSI] ncr53c400= [HW,SCSI] ncr53c400a= [HW,SCSI] ncr53c406a= [HW,SCSI] ncr53c8xx= [HW,SCSI] nfsaddrs= [NFS] nfsroot= [NFS] no387 [BUGS=ix86] Tells the kernel to use the 387 maths emulation library even if a 387 maths coprocessor is present. noapic [SMP,APIC] Tells the kernel not to make use of any APIC that may be present on the system. no-halt [BUGS=ix86] noinitrd [RAM] Tells the kernel not to load any configured initial ramdisc. no-scroll [VGA] nosmp [SMP] Tells an SMP kernel to act as a UP kernel. optcd= [HW,CD] panic= parport=0 [HW,PPT] Specify parallel ports. 0 or parport=auto disables. Use 'auto' to force the driver or parport=0xBBB[,IRQ[,DMA]] to use any IRQ/DMA settings detected (the default is to ignore detected IRQ/DMA settings because of possible conflicts). You can specify the base address, IRQ, and DMA settings; IRQ and DMA should be numbers, or 'auto' (for using detected settings on that particular port), or 'nofifo' (to avoid using a FIFO even if it is detected). Parallel ports are assigned in the order they are specified on the command line, starting with parport0. pas16= [HW,SCSI] pcbit= [HW,ISDN] pcd. [PARIDE] pci= [PCI] pd. [PARIDE] pf. [PARIDE] pg. [PARIDE] pirq= [SMP,APIC] plip= [PPT,NET] Parallel port network link. profile= prompt_ramdisk= [RAM] Whether to prompt for ramdisk before loading its contents into memory. pt. [PARIDE] ramdisk= [RAM] ramdisk_size= [RAM] ramdisk_start= [RAM] reboot= [BUGS=ix86] reserve= riscom8= [HW,SERIAL] ro [KNL] Mount root device read-only on boot. root= rw [KNL] Mount root device read-write on boot. sbpcd= [HW,CD] Soundblaster CD adapter. scsi_logging= [SCSI] sjcd= [HW,CD] sonycd535= [HW,CD] sound= [SOUND] soundmodem= [HW,AX25,SOUND] Sound cards used as AX.25 modems. specialix= [HW,SERIAL] Specialix multi-serial port adapter. st= [HW] st0x= [HW,SCSI] stram_swap= [HW] sym53c416= [HW,SCSI] sym53c8xx= [HW,SCSI] t128= [HW,SCSI] tmc8xx= [HW,SCSI] tmscsim= [HW,SCSI] tp720= [HW,PS2] u14-34f= [HW,SCSI] video= [FB] wd33c93= [HW,SCSI] wd7000= [HW,SCSI] wdt= [HW] xd= [HW,XT] xd_geo= [HW,XT]