diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 198 |
1 files changed, 87 insertions, 111 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7ce5ea9..fb80e9f 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -34,7 +34,6 @@ parameter is applicable: APIC APIC support is enabled. APM Advanced Power Management support is enabled. AX25 Appropriate AX.25 support is enabled. - CD Appropriate CD support is enabled. DRM Direct Rendering Management support is enabled. EDD BIOS Enhanced Disk Drive Services (EDD) is enabled EFI EFI Partitioning (GPT) is enabled @@ -170,7 +169,10 @@ and is between 256 and 4096 characters. It is defined in the file acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS Format: To spoof as Windows 98: ="Microsoft Windows" - acpi_osi= [HW,ACPI] empty param disables _OSI + acpi_osi= [HW,ACPI] Modify list of supported OS interface strings + acpi_osi="string1" # add string1 -- only one string + acpi_osi="!string2" # remove built-in string2 + acpi_osi= # disable all strings acpi_serialize [HW,ACPI] force serialization of AML methods @@ -235,16 +237,9 @@ and is between 256 and 4096 characters. It is defined in the file Disable PIN 1 of APIC timer Can be useful to work around chipset bugs. - ad1816= [HW,OSS] - Format: <io>,<irq>,<dma>,<dma2> - See also Documentation/sound/oss/AD1816. - ad1848= [HW,OSS] Format: <io>,<irq>,<dma>,<dma2>,<type> - adlib= [HW,OSS] - Format: <io> - advansys= [HW,SCSI] See header of drivers/scsi/advansys.c. @@ -323,9 +318,6 @@ and is between 256 and 4096 characters. It is defined in the file autotest [IA64] - aztcd= [HW,CD] Aztech CD268 CDROM driver - Format: <io>,0x79 (?) - baycom_epp= [HW,AX25] Format: <io>,<mode> @@ -368,10 +360,6 @@ and is between 256 and 4096 characters. It is defined in the file possible to determine what the correct size should be. This option provides an override for these situations. - cdu31a= [HW,CD] - Format: <io>,<irq>[,PAS] - See header of drivers/cdrom/cdu31a.c. - chandev= [HW,NET] Generic channel device initialisation checkreqprot [SELINUX] Set initial checkreqprot flag value. @@ -425,9 +413,6 @@ and is between 256 and 4096 characters. It is defined in the file hpet= [IA-32,HPET] option to disable HPET and use PIT. Format: disable - cm206= [HW,CD] - Format: { auto | [<io>,][<irq>] } - com20020= [HW,NET] ARCnet - COM20020 chipset Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]] @@ -459,13 +444,20 @@ and is between 256 and 4096 characters. It is defined in the file Documentation/networking/netconsole.txt for an alternative. - uart,io,<addr>[,options] - uart,mmio,<addr>[,options] + uart[8250],io,<addr>[,options] + uart[8250],mmio,<addr>[,options] Start an early, polled-mode console on the 8250/16550 UART at the specified I/O port or MMIO address, switching to the matching ttyS device later. The options are the same as for ttyS, above. + earlycon= [KNL] Output early console device and options. + uart[8250],io,<addr>[,options] + uart[8250],mmio,<addr>[,options] + Start an early, polled-mode console on the 8250/16550 + UART at the specified I/O port or MMIO address. + The options are the same as for ttyS, above. + cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] @@ -657,9 +649,6 @@ and is between 256 and 4096 characters. It is defined in the file gpt [EFI] Forces disk with valid GPT signature but invalid Protective MBR to be treated as GPT. - gscd= [HW,CD] - Format: <io> - gvp11= [HW,SCSI] hashdist= [KNL,NUMA] Large hashes allocated during boot @@ -823,14 +812,37 @@ and is between 256 and 4096 characters. It is defined in the file tasks in the system -- can cause problems and suboptimal load balancer performance. - isp16= [HW,CD] - Format: <io>,<irq>,<dma>,<setup> - iucv= [HW,NET] js= [HW,JOY] Analog joystick See Documentation/input/joystick.txt. + kernelcore=nn[KMG] [KNL,IA-32,IA-64,PPC,X86-64] This parameter + specifies the amount of memory usable by the kernel + for non-movable allocations. The requested amount is + spread evenly throughout all nodes in the system. The + remaining memory in each node is used for Movable + pages. In the event, a node is too small to have both + kernelcore and Movable pages, kernelcore pages will + take priority and other nodes will have a larger number + of kernelcore pages. The Movable zone is used for the + allocation of pages that may be reclaimed or moved + by the page migration subsystem. This means that + HugeTLB pages may not be allocated from this zone. + Note that allocations like PTEs-from-HighMem still + use the HighMem zone if it exists, and the Normal + zone if it does not. + + movablecore=nn[KMG] [KNL,IA-32,IA-64,PPC,X86-64] This parameter + is similar to kernelcore except it specifies the + amount of memory used for migratable allocations. + If both kernelcore and movablecore is specified, + then kernelcore will be at *least* the specified + value but may be more. If movablecore on its own + is specified, the administrator must be careful + that the amount of memory usable for all allocations + is not too small. + keepinitrd [HW,ARM] kstack=N [IA-32,X86-64] Print N words from the kernel stack @@ -964,11 +976,6 @@ and is between 256 and 4096 characters. It is defined in the file mcatest= [IA-64] - mcd= [HW,CD] - Format: <port>,<irq>,<mitsumi_bug_93_wait> - - mcdx= [HW,CD] - mce [IA-32] Machine Check Exception md= [HW] RAID subsystems devices and level @@ -1011,49 +1018,6 @@ and is between 256 and 4096 characters. It is defined in the file mga= [HW,DRM] - migration_cost= - [KNL,SMP] debug: override scheduler migration costs - Format: <level-1-usecs>,<level-2-usecs>,... - This debugging option can be used to override the - default scheduler migration cost matrix. The numbers - are indexed by 'CPU domain distance'. - E.g. migration_cost=1000,2000,3000 on an SMT NUMA - box will set up an intra-core migration cost of - 1 msec, an inter-core migration cost of 2 msecs, - and an inter-node migration cost of 3 msecs. - - WARNING: using the wrong values here can break - scheduler performance, so it's only for scheduler - development purposes, not production environments. - - migration_debug= - [KNL,SMP] migration cost auto-detect verbosity - Format=<0|1|2> - If a system's migration matrix reported at bootup - seems erroneous then this option can be used to - increase verbosity of the detection process. - We default to 0 (no extra messages), 1 will print - some more information, and 2 will be really - verbose (probably only useful if you also have a - serial console attached to the system). - - migration_factor= - [KNL,SMP] multiply/divide migration costs by a factor - Format=<percent> - This debug option can be used to proportionally - increase or decrease the auto-detected migration - costs for all entries of the migration matrix. - E.g. migration_factor=150 will increase migration - costs by 50%. (and thus the scheduler will be less - eager migrating cache-hot tasks) - migration_factor=80 will decrease migration costs - by 20%. (thus the scheduler will be more eager to - migrate tasks) - - WARNING: using the wrong values here can break - scheduler performance, so it's only for scheduler - development purposes, not production environments. - mousedev.tap_time= [MOUSE] Maximum time between finger touching and leaving touchpad surface for touch to be considered @@ -1190,6 +1154,8 @@ and is between 256 and 4096 characters. It is defined in the file nointroute [IA-64] + nojitter [IA64] Disables jitter checking for ITC timers. + nolapic [IA-32,APIC] Do not enable or use the local APIC. nolapic_timer [IA-32,APIC] Do not use the local APIC timer. @@ -1221,6 +1187,8 @@ and is between 256 and 4096 characters. It is defined in the file nosmp [SMP] Tells an SMP kernel to act as a UP kernel. + nosoftlockup [KNL] Disable the soft-lockup detector. + nosync [HW,M68K] Disables sync negotiation for all devices. notsc [BUGS=IA-32] Disable Time Stamp Counter @@ -1229,20 +1197,19 @@ and is between 256 and 4096 characters. It is defined in the file nowb [ARM] + numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA. + one of ['zone', 'node', 'default'] can be specified + This can be set from sysctl after boot. + See Documentation/sysctl/vm.txt for details. + nr_uarts= [SERIAL] maximum number of UARTs to be registered. opl3= [HW,OSS] Format: <io> - opl3sa2= [HW,OSS] Format: - <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple] - oprofile.timer= [HW] Use timer interrupt instead of performance counters - optcd= [HW,CD] - Format: <io> - osst= [HW,SCSI] SCSI Tape Driver Format: <buffer_size>,<write_threshold> See also Documentation/scsi/st.txt. @@ -1421,6 +1388,15 @@ and is between 256 and 4096 characters. It is defined in the file autoconfiguration. Ranges are in pairs (memory base and size). + print-fatal-signals= + [KNL] debug: print fatal signals + print-fatal-signals=1: print segfault info to + the kernel console. + default: off. + + printk.time= Show timing data prefixed to each printk message line + Format: <bool> (1/Y/y=enable, 0/N/n=disable) + profile= [KNL] Enable kernel profiling via /proc/profile Format: [schedule,]<number> Param: "schedule" - profile schedule points. @@ -1533,6 +1509,10 @@ and is between 256 and 4096 characters. It is defined in the file rootfstype= [KNL] Set root filesystem type + rootwait [KNL] Wait (indefinitely) for root device to show up. + Useful for devices that are detected asynchronously + (e.g. USB and MMC devices). + rw [KNL] Mount root device read-write on boot S [KNL] Run init in single mode @@ -1545,11 +1525,6 @@ and is between 256 and 4096 characters. It is defined in the file sbni= [NET] Granch SBNI12 leased line adapter - sbpcd= [HW,CD] Soundblaster CD adapter - Format: <io>,<type> - See a comment before function sbpcd_setup() in - drivers/cdrom/sbpcd.c. - sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver Format: <io>[,<timeout>[,<isapnp>]] @@ -1602,41 +1577,41 @@ and is between 256 and 4096 characters. It is defined in the file simeth= [IA-64] simscsi= - sjcd= [HW,CD] - Format: <io>,<irq>,<dma> - See header of drivers/cdrom/sjcd.c. - slram= [HW,MTD] - slub_debug [MM, SLUB] - Enabling slub_debug allows one to determine the culprit - if slab objects become corrupted. Enabling slub_debug - creates guard zones around objects and poisons objects - when not in use. Also tracks the last alloc / free. - For more information see Documentation/vm/slub.txt. + slub_debug[=options[,slabs]] [MM, SLUB] + Enabling slub_debug allows one to determine the + culprit if slab objects become corrupted. Enabling + slub_debug can create guard zones around objects and + may poison objects when not in use. Also tracks the + last alloc / free. For more information see + Documentation/vm/slub.txt. slub_max_order= [MM, SLUB] - Determines the maximum allowed order for slabs. Setting - this too high may cause fragmentation. - For more information see Documentation/vm/slub.txt. + Determines the maximum allowed order for slabs. + A high setting may cause OOMs due to memory + fragmentation. For more information see + Documentation/vm/slub.txt. slub_min_objects= [MM, SLUB] - The minimum objects per slab. SLUB will increase the - slab order up to slub_max_order to generate a - sufficiently big slab to satisfy the number of objects. - The higher the number of objects the smaller the overhead - of tracking slabs. + The minimum number of objects per slab. SLUB will + increase the slab order up to slub_max_order to + generate a sufficiently large slab able to contain + the number of objects indicated. The higher the number + of objects the smaller the overhead of tracking slabs + and the less frequently locks need to be acquired. For more information see Documentation/vm/slub.txt. slub_min_order= [MM, SLUB] Determines the mininum page order for slabs. Must be - lower than slub_max_order + lower than slub_max_order. For more information see Documentation/vm/slub.txt. slub_nomerge [MM, SLUB] - Disable merging of slabs of similar size. May be + Disable merging of slabs with similar size. May be necessary if there is some reason to distinguish - allocs to different slabs. + allocs to different slabs. Debug options disable + merging on their own. For more information see Documentation/vm/slub.txt. smart2= [HW] @@ -1778,9 +1753,6 @@ and is between 256 and 4096 characters. It is defined in the file snd-ymfpci= [HW,ALSA] - sonycd535= [HW,CD] - Format: <io>[,<irq>] - sonypi.*= [HW] Sony Programmable I/O Control Device driver See Documentation/sonypi.txt @@ -1852,6 +1824,7 @@ and is between 256 and 4096 characters. It is defined in the file Set number of hash buckets for TCP connection time Show timing data prefixed to each printk message line + [deprecated, see 'printk.time'] tipar.timeout= [HW,PPT] Set communications timeout in tenths of a second @@ -1909,11 +1882,14 @@ and is between 256 and 4096 characters. It is defined in the file usbhid.mousepoll= [USBHID] The interval which mice are to be polled at. - vdso= [IA-32,SH] + vdso= [IA-32,SH,x86-64] vdso=2: enable compat VDSO (default with COMPAT_VDSO) vdso=1: enable VDSO (default) vdso=0: disable VDSO mapping + vector= [IA-64,SMP] + vector=percpu: enable percpu vector domain + video= [FB] Frame buffer configuration See Documentation/fb/modedb.txt. |