X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=Documentation%2Fkernel-parameters.txt;h=6e92ba61f7c0ea18b86557eec2bd17f2ece5d9ca;hb=50b520d4efbce45281f58112789470ec7965fd33;hp=149f62ba14a5023a59a1cbaa53550b053950edb2;hpb=cae2ed9aa573415c6e5de9a09b7ff0d74af793bc;p=safe%2Fjmp%2Flinux-2.6 diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 149f62b..6e92ba6 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -48,6 +48,7 @@ parameter is applicable: ISAPNP ISA PnP code is enabled. ISDN Appropriate ISDN support is enabled. JOY Appropriate joystick support is enabled. + LIBATA Libata driver is enabled LP Printer support is enabled. LOOP Loopback device support is enabled. M68k M68k architecture is enabled. @@ -104,12 +105,22 @@ loader, and have no meaning to the kernel directly. Do not modify the syntax of boot loader parameters without extreme need or coordination with . +There are also arch-specific kernel-parameters not documented here. +See for example . + 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. +The number of kernel parameters is not limited, but the length of the +complete command line (parameters including spaces etc.) is limited to +a fixed number of characters. This limit depends on the architecture +and is between 256 and 4096 characters. It is defined in the file +./include/asm/setup.h as COMMAND_LINE_SIZE. + + 53c7xx= [HW,SCSI] Amiga SCSI controllers See header of drivers/scsi/53c7xx.c. See also Documentation/scsi/ncr53c7xx.txt. @@ -157,6 +168,10 @@ running once the system is up. acpi_skip_timer_override [HW,ACPI] Recognize and ignore IRQ0/pin2 Interrupt Override. For broken nForce2 BIOS resulting in XT-PIC timer. + acpi_use_timer_override [HW,ACPI} + Use timer override. For some broken Nvidia NF5 boards + that require a timer override, but don't have + HPET acpi_dbg_layer= [HW,ACPI] Format: @@ -282,9 +297,6 @@ running once the system is up. autotest [IA64] - awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth - Format: ,, - aztcd= [HW,CD] Aztech CD268 CDROM driver Format: ,0x79 (?) @@ -348,11 +360,16 @@ running once the system is up. clock= [BUGS=IA-32, HW] gettimeofday clocksource override. [Deprecated] - Forces specified clocksource (if avaliable) to be used + Forces specified clocksource (if available) to be used when calculating gettimeofday(). If specified - clocksource is not avalible, it defaults to PIT. + clocksource is not available, it defaults to PIT. Format: { pit | tsc | cyclone | pmtmr } + code_bytes [IA32] How many bytes of object code to print in an + oops report. + Range: 0 - 8192 + Default: 64 + disable_8254_timer enable_8254_timer [IA32/X86_64] Disable/Enable interrupt 0 timer routing @@ -529,10 +546,6 @@ running once the system is up. Default value is 0. Value can be changed at runtime via /selinux/enforce. - es1370= [HW,OSS] - Format: [,] - See also header of sound/oss/es1370.c. - es1371= [HW,OSS] Format: ,[,[]] See also header of sound/oss/es1371.c. @@ -544,6 +557,13 @@ running once the system is up. eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog. Format: [,] + failslab= + fail_page_alloc= + fail_make_request=[KNL] + General fault injection mechanism. + Format: ,,, + See also /Documentation/fault-injection/. + fd_mcs= [HW,SCSI] See header of drivers/scsi/fd_mcs.c. @@ -553,9 +573,6 @@ running once the system is up. floppy= [HW] See Documentation/floppy.txt. - ftape= [HW] Floppy Tape subsystem debugging options. - See Documentation/ftape.txt. - gamecon.map[2|3]= [HW,JOY] Multisystem joystick and NES/SNES/PSX pad support via parallel port (up to 5 devices per port) @@ -573,11 +590,6 @@ running once the system is up. gscd= [HW,CD] Format: - gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller - - gus= [HW,OSS] - Format: ,,, - gvp11= [HW,SCSI] hashdist= [KNL,NUMA] Large hashes allocated during boot @@ -598,16 +610,18 @@ running once the system is up. highmem otherwise. This also works to reduce highmem size on bigger boxes. + highres= [KNL] Enable/disable high resolution timer mode. + Valid parameters: "on", "off" + Default: "on" + hisax= [HW,ISDN] See Documentation/isdn/README.HiSax. hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages. - noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing - i8042.direct [HW] Put keyboard port into non-translated mode - i8042.dumbkbd [HW] Pretend that controlled can only read data from - keyboard and can not control its state + i8042.dumbkbd [HW] Pretend that controller can only read data from + keyboard and cannot control its state (Don't attempt to blink the leds) i8042.noaux [HW] Don't check for auxiliary (== mouse) port i8042.nokbd [HW] Don't check/create keyboard port @@ -654,6 +668,10 @@ running once the system is up. idle= [HW] Format: idle=poll or idle=halt + ignore_loglevel [KNL] + Ignore loglevel setting - this will print /all/ + kernel messages to the console. Useful for debugging. + ihash_entries= [KNL] Set number of hash buckets for inode cache. @@ -697,6 +715,12 @@ running once the system is up. ips= [HW,SCSI] Adaptec / IBM ServeRAID controller See header of drivers/scsi/ips.c. + ports= [IP_VS_FTP] IPVS ftp helper module + Default is 21. + Up to 8 (IP_VS_APP_MAX_PORTS) ports + may be specified. + Format: ,.... + irqfixup [HW] When an interrupt is not handled search all handlers for it. Intended to get systems with badly broken @@ -712,7 +736,12 @@ running once the system is up. Format: ,,, isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler. - Format: ,..., + Format: + ,..., + or + - (must be a positive range in ascending order) + or a mixture + ,...,- This option can be used to specify one or more CPUs to isolate from the general SMP balancing and scheduling algorithms. The only way to move a process onto or off @@ -830,18 +859,19 @@ running once the system is up. (machvec) in a generic kernel. Example: machvec=hpzx1_swiotlb - mad16= [HW,OSS] Format: - ,,,,,, - - maui= [HW,OSS] - Format: , - max_loop= [LOOP] Maximum number of loopback devices that can be mounted Format: <1-256> maxcpus= [SMP] Maximum number of processors that an SMP kernel - should make use of + should make use of. + Using "nosmp" or "maxcpus=0" will disable SMP + entirely (the MPS table probe still happens, though). + A command-line option of "maxcpus=", where + is an integer greater than 0, limits the maximum number + of CPUs activated in SMP mode to . + Using "maxcpus=1" on an SMP kernel is the trivial + case of an SMP kernel with only one CPU. max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or equal to this physical address is ignored. @@ -1016,6 +1046,14 @@ running once the system is up. emulation library even if a 387 maths coprocessor is present. + noacpi [LIBATA] Disables use of ACPI in libata suspend/resume + when set. + Format: + + noaliencache [MM, NUMA] Disables the allcoation of alien caches in + the slab allocator. Saves per-node memory, but will + impact performance on real NUMA hardware. + noalign [KNL,ARM] noapic [SMP,APIC] Tells the kernel to not make use of any @@ -1029,6 +1067,8 @@ running once the system is up. nocache [ARM] + nodelayacct [KNL] Disable per-task delay accounting + nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects. noexec [IA-64] @@ -1054,9 +1094,18 @@ running once the system is up. in certain environments such as networked servers or real-time systems. + nohz= [KNL] Boottime enable/disable dynamic ticks + Valid arguments: on, off + Default: on + + noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing + noirqdebug [IA-32] Disables the code which attempts to detect and disable unhandled interrupt sources. + no_timer_check [IA-32,X86_64,APIC] Disables the code which tests for + broken timer IRQ sources. + noisapnp [ISAPNP] Disables ISA PnP code. noinitrd [RAM] Tells the kernel not to load any configured @@ -1101,9 +1150,6 @@ running once the system is up. opl3= [HW,OSS] Format: - opl3sa= [HW,OSS] - Format: ,,,,, - opl3sa2= [HW,OSS] Format: ,,,,,,,[,, - step/bucket size as a power of 2 for statistical time based profiling. + Param: "sleep" - profile D-state sleeping (millisecs) processor.max_cstate= [HW,ACPI] Limit processor to maximum C-state @@ -1314,7 +1376,7 @@ running once the system is up. pt. [PARIDE] See Documentation/paride.txt. - quiet= [KNL] Disable log messages + quiet [KNL] Disable most log messages r128= [HW,DRM] @@ -1340,10 +1402,6 @@ running once the system is up. rcu.qlowmark= [KNL,BOOT] Set threshold of queued RCU callbacks below which batch limiting is re-enabled. - rcu.rsinterval= [KNL,BOOT,SMP] Set the number of additional - RCU callbacks to queued before forcing reschedule - on all cpus. - rdinit= [KNL] Format: Run specified binary instead of /init from the ramdisk, @@ -1351,13 +1409,29 @@ running once the system is up. reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode Format: [,[,...]] - See arch/*/kernel/reboot.c. + See arch/*/kernel/reboot.c or arch/*/kernel/process.c reserve= [KNL,BUGS] Force the kernel to ignore some iomem area + reservetop= [IA-32] + Format: nn[KMG] + Reserves a hole at the top of the kernel virtual + address space. + + reset_devices [KNL] Force drivers to reset the underlying device + during initialization. + resume= [SWSUSP] Specify the partition device for software suspend + resume_offset= [SWSUSP] + Specify the offset from the beginning of the partition + given by "resume=" at which the swap header is located, + in units (needed only for swap files). + See Documentation/power/swsusp-and-swap-files.txt + + retain_initrd [RAM] Keep initrd memory after extraction + rhash_entries= [KNL,NET] Set number of hash buckets for route cache @@ -1408,6 +1482,11 @@ running once the system is up. scsi_logging= [SCSI] + scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are + discovered. async scans them in kernel threads, + allowing boot to proceed. none ignores them, expecting + user space to do the scan. + selinux [SELINUX] Disable or enable SELinux at boot time. Format: { "0" | "1" } See security/selinux/Kconfig help text. @@ -1430,9 +1509,6 @@ running once the system is up. sg_def_reserved_size= [SCSI] - sgalaxy= [HW,OSS] - Format: ,,,, - shapers= [NET] Maximal number of shapers. @@ -1573,9 +1649,6 @@ running once the system is up. snd-ymfpci= [HW,ALSA] - sonicvibes= [HW,OSS] - Format: - sonycd535= [HW,CD] Format: [,] @@ -1612,6 +1685,22 @@ running once the system is up. stifb= [HW] Format: bpp:[:[:...]] + sunrpc.pool_mode= + [NFS] + Control how the NFS server code allocates CPUs to + service thread pools. Depending on how many NICs + you have and where their interrupts are bound, this + option will affect which CPUs will do NFS serving. + Note: this parameter cannot be changed while the + NFS server is running. + + auto the server chooses an appropriate mode + automatically using heuristics + global a single global pool contains all CPUs + percpu one pool for each CPU + pernode one pool for each NUMA node (equivalent + to global on non-NUMA machines) + swiotlb= [IA-64] Number of I/O TLB slabs switches= [HW,M68k] @@ -1619,6 +1708,12 @@ running once the system is up. sym53c416= [HW,SCSI] See header of drivers/scsi/sym53c416.c. + sysrq_always_enabled + [KNL] + Ignore sysrq setting - this boot parameter will + neutralize any effect of /proc/sys/kernel/sysrq. + Useful for debugging. + t128= [HW,SCSI] See header of drivers/scsi/t128.c. @@ -1671,6 +1766,21 @@ running once the system is up. uart6850= [HW,OSS] Format: , + uhci-hcd.ignore_oc= + [USB] Ignore overcurrent events (default N). + Some badly-designed motherboards generate lots of + bogus events, for ports that aren't wired to + anything. Set this parameter to avoid log spamming. + Note that genuine overcurrent events won't be + reported either. + + usbcore.autosuspend= + [USB] The autosuspend time delay (in seconds) used + for newly-detected USB devices (default 2). This + is the time required before an idle device will be + autosuspended. Devices for which the delay is set + to 0 won't be autosuspended at all. + usbhid.mousepoll= [USBHID] The interval which mice are to be polled at. @@ -1725,6 +1835,9 @@ running once the system is up. norandmaps Don't use address space randomization Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space + unwind_debug=N N > 0 will enable dwarf2 unwinder debugging + This is useful to get more information why + you got a "dwarf2 unwinder stuck" ______________________________________________________________________