diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 94 |
1 files changed, 55 insertions, 39 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index cdd2a6e8a3b7..d18a9e12152a 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -43,11 +43,11 @@ parameter is applicable: AVR32 AVR32 architecture is enabled. AX25 Appropriate AX.25 support is enabled. BLACKFIN Blackfin architecture is enabled. + DRM Direct Rendering Management support is enabled. + DYNAMIC_DEBUG Build in debug messages and enable them at runtime EDD BIOS Enhanced Disk Drive Services (EDD) is enabled EFI EFI Partitioning (GPT) is enabled EIDE EIDE/ATAPI support is enabled. - DRM Direct Rendering Management support is enabled. - DYNAMIC_DEBUG Build in debug messages and enable them at runtime FB The frame buffer device is enabled. GCOV GCOV profiling is enabled. HW Appropriate hardware is enabled. @@ -144,6 +144,11 @@ 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. +Finally, the [KMG] suffix is commonly described after a number of kernel +parameter values. These 'K', 'M', and 'G' letters represent the _binary_ +multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30 +bytes respectively. Such letter suffixes can also be entirely omitted. + acpi= [HW,ACPI,X86] Advanced Configuration and Power Interface @@ -199,11 +204,6 @@ and is between 256 and 4096 characters. It is defined in the file unusable. The "log_buf_len" parameter may be useful if you need to capture more output. - acpi_display_output= [HW,ACPI] - acpi_display_output=vendor - acpi_display_output=video - See above. - acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs default in APIC mode @@ -403,6 +403,10 @@ and is between 256 and 4096 characters. It is defined in the file bttv.pll= See Documentation/video4linux/bttv/Insmod-options bttv.tuner= and Documentation/video4linux/bttv/CARDLIST + bulk_remove=off [PPC] This parameter disables the use of the pSeries + firmware feature for flushing multiple hpte entries + at a time. + c101= [NET] Moxa C101 synchronous serial card cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection. @@ -546,16 +550,20 @@ and is between 256 and 4096 characters. It is defined in the file Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] - crashkernel=nn[KMG]@ss[KMG] - [KNL] Reserve a chunk of physical memory to - hold a kernel to switch to with kexec on panic. + crashkernel=size[KMG][@offset[KMG]] + [KNL] Using kexec, Linux can switch to a 'crash kernel' + upon panic. This parameter reserves the physical + memory region [offset, offset + size] for that kernel + image. If '@offset' is omitted, then a suitable offset + is selected automatically. Check + Documentation/kdump/kdump.txt for further details. crashkernel=range1:size1[,range2:size2,...][@offset] [KNL] Same as above, but depends on the memory in the running system. The syntax of range is start-[end] where start and end are both a memory unit (amount[KMG]). See also - Documentation/kdump/kdump.txt for a example. + Documentation/kdump/kdump.txt for an example. cs89x0_dma= [HW,NET] Format: <dma> @@ -618,6 +626,10 @@ and is between 256 and 4096 characters. It is defined in the file disable= [IPV6] See Documentation/networking/ipv6.txt. + disable_ddw [PPC/PSERIES] + Disable Dynamic DMA Window support. Use this if + to workaround buggy firmware. + disable_ipv6= [IPV6] See Documentation/networking/ipv6.txt. @@ -655,11 +667,6 @@ and is between 256 and 4096 characters. It is defined in the file dscc4.setup= [NET] - dynamic_printk Enables pr_debug()/dev_dbg() calls if - CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. - These can also be switched on/off via - <debugfs>/dynamic_printk/modules - earlycon= [KNL] Output early console device and options. uart[8250],io,<addr>[,options] uart[8250],mmio,<addr>[,options] @@ -884,6 +891,7 @@ and is between 256 and 4096 characters. It is defined in the file controller i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX controllers + i8042.notimeout [HW] Ignore timeout condition signalled by conroller i8042.reset [HW] Reset the controller during init and cleanup i8042.unlock [HW] Unlock (ignore) the keylock @@ -1267,10 +1275,9 @@ and is between 256 and 4096 characters. It is defined in the file 6 (KERN_INFO) informational 7 (KERN_DEBUG) debug-level messages - log_buf_len=n Sets the size of the printk ring buffer, in bytes. - Format: { n | nk | nM } - n must be a power of two. The default size - is set in the kernel config file. + log_buf_len=n[KMG] Sets the size of the printk ring buffer, + in bytes. n must be a power of two. The default + size is set in the kernel config file. logo.nologo [FB] Disables display of the built-in Linux logo. This may be used to provide more screen space for @@ -1490,6 +1497,10 @@ and is between 256 and 4096 characters. It is defined in the file mtdparts= [MTD] See drivers/mtd/cmdlinepart.c. + multitce=off [PPC] This parameter disables the use of the pSeries + firmware feature for updating multiple TCE entries + at a time. + onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration Format: [die0_boundary][,die0_lock][,die1_boundary][,die1_lock] @@ -1573,26 +1584,26 @@ and is between 256 and 4096 characters. It is defined in the file of returning the full 64-bit number. The default is to return 64-bit inode numbers. + nfs.nfs4_disable_idmapping= + [NFSv4] When set, this option disables the NFSv4 + idmapper on the client, but only if the mount + is using the 'sec=sys' security flavour. This may + make migration from legacy NFSv2/v3 systems easier + provided that the server has the appropriate support. + The default is to always enable NFSv4 idmapping. + nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take when a NMI is triggered. Format: [state][,regs][,debounce][,die] nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels Format: [panic,][num] - Valid num: 0,1,2 + Valid num: 0 0 - turn nmi_watchdog off - 1 - use the IO-APIC timer for the NMI watchdog - 2 - use the local APIC for the NMI watchdog using - a performance counter. Note: This will use one - performance counter and the local APIC's performance - vector. When panic is specified, panic when an NMI watchdog timeout occurs. This is useful when you use a panic=... timeout and need the box quickly up again. - Instead of 1 and 2 it is possible to use the following - symbolic names: lapic and ioapic - Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic netpoll.carrier_timeout= [NET] Specifies amount of time (in seconds) that @@ -1622,6 +1633,8 @@ and is between 256 and 4096 characters. It is defined in the file noapic [SMP,APIC] Tells the kernel to not make use of any IOAPICs that may be present in the system. + noautogroup Disable scheduler automatic task group creation. + nobats [PPC] Do not use BATs for mapping kernel lowmem on "Classic" PPC cores. @@ -1707,6 +1720,9 @@ and is between 256 and 4096 characters. It is defined in the file no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver + no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page + fault handling. + nolapic [X86-32,APIC] Do not enable or use the local APIC. nolapic_timer [X86-32,APIC] Do not use the local APIC timer. @@ -1759,7 +1775,7 @@ and is between 256 and 4096 characters. It is defined in the file nousb [USB] Disable the USB subsystem - nowatchdog [KNL] Disable the lockup detector. + nowatchdog [KNL] Disable the lockup detector (NMI watchdog). nowb [ARM] @@ -2175,11 +2191,6 @@ and is between 256 and 4096 characters. It is defined in the file reset_devices [KNL] Force drivers to reset the underlying device during initialization. - resource_alloc_from_bottom - Allocate new resources from the beginning of available - space, not the end. If you need to use this, please - report a bug. - resume= [SWSUSP] Specify the partition device for software suspend @@ -2445,6 +2456,10 @@ and is between 256 and 4096 characters. It is defined in the file <deci-seconds>: poll all this frequency 0: no polling (default) + threadirqs [KNL] + Force threading of all interrupt handlers except those + marked explicitely IRQF_NO_THREAD. + topology= [S390] Format: {off | on} Specify if the kernel should make use of the cpu @@ -2472,12 +2487,13 @@ and is between 256 and 4096 characters. It is defined in the file to facilitate early boot debugging. See also Documentation/trace/events.txt - tsc= Disable clocksource-must-verify flag for TSC. + tsc= Disable clocksource stability checks for TSC. Format: <string> [x86] reliable: mark tsc clocksource as reliable, this - disables clocksource verification at runtime. - Used to enable high-resolution timer mode on older - hardware, and in virtualized environment. + disables clocksource verification at runtime, as well + as the stability checks done at bootup. Used to enable + high-resolution timer mode on older hardware, and in + virtualized environment. [x86] noirqtime: Do not use TSC to do irq accounting. Used to run time disable IRQ_TIME_ACCOUNTING on any platforms where RDTSC is slow and this accounting |