diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 96 |
1 files changed, 73 insertions, 23 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 6172e4360f60..fd5cac013037 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -17,6 +17,12 @@ are specified on the kernel command line with the module name plus usbcore.blinkenlights=1 +Hyphens (dashes) and underscores are equivalent in parameter names, so + log_buf_len=1M print-fatal-signals=1 +can also be entered as + log-buf-len=1M print_fatal_signals=1 + + This document may not be entirely up to date and comprehensive. The command "modinfo -p ${modulename}" shows a current list of all parameters of a loadable module. Loadable modules, after being loaded into the running kernel, also @@ -134,7 +140,7 @@ and is between 256 and 4096 characters. It is defined in the file ./include/asm/setup.h as COMMAND_LINE_SIZE. - acpi= [HW,ACPI,X86-64,i386] + acpi= [HW,ACPI,X86] Advanced Configuration and Power Interface Format: { force | off | ht | strict | noirq | rsdt } force -- enable ACPI if default was off @@ -218,7 +224,7 @@ and is between 256 and 4096 characters. It is defined in the file acpi_osi="!string2" # remove built-in string2 acpi_osi= # disable all strings - acpi_pm_good [X86-32,X86-64] + acpi_pm_good [X86] Override the pmtimer bug detection: force the kernel to assume that this machine's pmtimer latches its value and always returns good values. @@ -231,6 +237,35 @@ and is between 256 and 4096 characters. It is defined in the file power state again in power transition. 1 : disable the power state check + acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode + Format: { level | edge | high | low } + + acpi_serialize [HW,ACPI] force serialization of AML methods + + acpi_skip_timer_override [HW,ACPI] + Recognize and ignore IRQ0/pin2 Interrupt Override. + For broken nForce2 BIOS resulting in XT-PIC timer. + + acpi_sleep= [HW,ACPI] Sleep options + Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, + old_ordering, s4_nonvs } + See Documentation/power/video.txt for information on + s3_bios and s3_mode. + s3_beep is for debugging; it makes the PC's speaker beep + as soon as the kernel's real-mode entry point is called. + s4_nohwsig prevents ACPI hardware signature from being + used during resume from hibernation. + old_ordering causes the ACPI 1.0 ordering of the _PTS + control method, with respect to putting devices into + low power states, to be enforced (the ACPI 2.0 ordering + of _PTS is used by default). + s4_nonvs prevents the kernel from saving/restoring the + ACPI NVS memory during hibernation. + + 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_enforce_resources= [ACPI] { strict | lax | no } Check for resource conflicts between native drivers @@ -250,6 +285,9 @@ and is between 256 and 4096 characters. It is defined in the file ad1848= [HW,OSS] Format: <io>,<irq>,<dma>,<dma2>,<type> + add_efi_memmap [EFI; X86] Include EFI memory map in + kernel's map of available physical RAM. + advansys= [HW,SCSI] See header of drivers/scsi/advansys.c. @@ -313,7 +351,7 @@ and is between 256 and 4096 characters. It is defined in the file not play well with APC CPU idle - disable it if you have APC and your system crashes randomly. - apic= [APIC,i386] Advanced Programmable Interrupt Controller + apic= [APIC,X86-32] Advanced Programmable Interrupt Controller Change the output verbosity whilst booting Format: { quiet (default) | verbose | debug } Change the amount of debugging information output @@ -459,7 +497,7 @@ and is between 256 and 4096 characters. It is defined in the file Also note the kernel might malfunction if you disable some critical bits. - code_bytes [IA32/X86_64] How many bytes of object code to print + code_bytes [X86] How many bytes of object code to print in an oops report. Range: 0 - 8192 Default: 64 @@ -592,7 +630,7 @@ and is between 256 and 4096 characters. It is defined in the file MTRR settings. This parameter disables that behavior, possibly causing your machine to run very slowly. - disable_timer_pin_1 [i386,x86-64] + disable_timer_pin_1 [X86] Disable PIN 1 of APIC timer Can be useful to work around chipset bugs. @@ -624,7 +662,7 @@ and is between 256 and 4096 characters. It is defined in the file UART at the specified I/O port or MMIO address. The options are the same as for ttyS, above. - earlyprintk= [X86-32,X86-64,SH,BLACKFIN] + earlyprintk= [X86,SH,BLACKFIN] earlyprintk=vga earlyprintk=serial[,ttySn[,baudrate]] earlyprintk=dbgp @@ -659,7 +697,7 @@ and is between 256 and 4096 characters. It is defined in the file See Documentation/block/as-iosched.txt and Documentation/block/deadline-iosched.txt for details. - elfcorehdr= [IA64,PPC,SH,X86-32,X86_64] + elfcorehdr= [IA64,PPC,SH,X86] Specifies physical address of start of kernel core image elf header. Generally kexec loader will pass this option to capture kernel. @@ -670,7 +708,7 @@ and is between 256 and 4096 characters. It is defined in the file to discrete, to make X server driver able to add WB entry later. This parameter enables that. - enable_timer_pin_1 [i386,x86-64] + enable_timer_pin_1 [X86] Enable PIN 1 of APIC timer Can be useful to work around chipset bugs (in particular on some ATI chipsets). @@ -743,7 +781,7 @@ and is between 256 and 4096 characters. It is defined in the file hashdist= [KNL,NUMA] Large hashes allocated during boot are distributed across NUMA nodes. Defaults on - for IA-64, off otherwise. + for 64bit NUMA, off otherwise. Format: 0 | 1 (for off | on) hcl= [IA-64] SGI's Hardware Graph compatibility layer @@ -938,7 +976,7 @@ and is between 256 and 4096 characters. It is defined in the file See comment before marvel_specify_io7 in arch/alpha/kernel/core_marvel.c. - io_delay= [X86-32,X86-64] I/O delay method + io_delay= [X86] I/O delay method 0x80 Standard port 0x80 based delay 0xed @@ -1000,7 +1038,7 @@ and is between 256 and 4096 characters. It is defined in the file keepinitrd [HW,ARM] - kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter + kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] 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 @@ -1034,7 +1072,7 @@ and is between 256 and 4096 characters. It is defined in the file Configure the RouterBoard 532 series on-chip Ethernet adapter MAC address. - kstack=N [X86-32,X86-64] Print N words from the kernel stack + kstack=N [X86] Print N words from the kernel stack in oops dumps. l2cr= [PPC] @@ -1044,7 +1082,7 @@ and is between 256 and 4096 characters. It is defined in the file lapic [X86-32,APIC] Enable the local APIC even if BIOS disabled it. - lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer + lapic_timer_c2_ok [X86,APIC] trust the local apic timer in C2 power state. libata.dma= [LIBATA] DMA control @@ -1229,7 +1267,7 @@ and is between 256 and 4096 characters. It is defined in the file [KNL,SH] Allow user to override the default size for per-device physically contiguous DMA buffers. - memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact + memmap=exactmap [KNL,X86] Enable setting of an exact E820 memory map, as specified by the user. Such memmap=exactmap lines can be constructed based on BIOS output or other requirements. See the memmap=nn@ss @@ -1320,7 +1358,7 @@ and is between 256 and 4096 characters. It is defined in the file mousedev.yres= [MOUSE] Vertical screen resolution, used for devices reporting absolute coordinates, such as tablets - movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter + movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter is similar to kernelcore except it specifies the amount of memory used for migratable allocations. If both kernelcore and movablecore is specified, @@ -1422,7 +1460,7 @@ and is between 256 and 4096 characters. It is defined in the file when a NMI is triggered. Format: [state][,regs][,debounce][,die] - nmi_watchdog= [KNL,BUGS=X86-32,X86-64] Debugging features for SMP kernels + nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels Format: [panic,][num] Valid num: 0,1,2 0 - turn nmi_watchdog off @@ -1475,11 +1513,11 @@ and is between 256 and 4096 characters. It is defined in the file nodsp [SH] Disable hardware DSP at boot time. - noefi [X86-32,X86-64] Disable EFI runtime services support. + noefi [X86] Disable EFI runtime services support. noexec [IA-64] - noexec [X86-32,X86-64] + noexec [X86] On X86-32 available only on PAE configured kernels. noexec=on: enable non-executable mappings (default) noexec=off: disable non-executable mappings @@ -1497,6 +1535,10 @@ and is between 256 and 4096 characters. It is defined in the file register save and restore. The kernel will only save legacy floating-point registers on task switch. + noxsave [BUGS=X86] Disables x86 extended register state save + and restore using xsave. The kernel will fallback to + enabling legacy floating-point and sse state. + nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or wfi(ARM) instruction doesn't work correctly and not to use it. This is also useful when using JTAG debugger. @@ -1525,7 +1567,7 @@ and is between 256 and 4096 characters. It is defined in the file noirqdebug [X86-32] Disables the code which attempts to detect and disable unhandled interrupt sources. - no_timer_check [X86-32,X86_64,APIC] Disables the code which tests for + no_timer_check [X86,APIC] Disables the code which tests for broken timer IRQ sources. noisapnp [ISAPNP] Disables ISA PnP code. @@ -1588,6 +1630,8 @@ and is between 256 and 4096 characters. It is defined in the file nowb [ARM] + nox2apic [X86-64,APIC] Do not enable x2APIC mode. + nptcg= [IA64] Override max number of concurrent global TLB purges which is reported from either PAL_VM_SUMMARY or SAL PALO. @@ -1689,7 +1733,7 @@ and is between 256 and 4096 characters. It is defined in the file disable the use of PCIE advanced error reporting. nodomains [PCI] Disable support for multiple PCI root domains (aka PCI segments, in ACPI-speak). - nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI + nommconf [X86] Disable use of MMCONFIG for PCI Configuration nomsi [MSI] If the PCI_MSI kernel config parameter is enabled, this kernel boot option can be used to @@ -1838,6 +1882,12 @@ and is between 256 and 4096 characters. It is defined in the file autoconfiguration. Ranges are in pairs (memory base and size). + ports= [IP_VS_FTP] IPVS ftp helper module + Default is 21. + Up to 8 (IP_VS_APP_MAX_PORTS) ports + may be specified. + Format: <port>,<port>.... + print-fatal-signals= [KNL] debug: print fatal signals print-fatal-signals=1: print segfault info to @@ -2380,7 +2430,7 @@ and is between 256 and 4096 characters. It is defined in the file reported either. unknown_nmi_panic - [X86-32,X86-64] + [X86] Set unknown_nmi_panic=1 early on boot. usbcore.autosuspend= @@ -2447,12 +2497,12 @@ and is between 256 and 4096 characters. It is defined in the file medium is write-protected). Example: quirks=0419:aaf5:rl,0421:0433:rc - vdso= [X86-32,SH,x86-64] + vdso= [X86,SH] vdso=2: enable compat VDSO (default with COMPAT_VDSO) vdso=1: enable VDSO (default) vdso=0: disable VDSO mapping - vdso32= [X86-32,X86-64] + vdso32= [X86] vdso32=2: enable compat VDSO (default with COMPAT_VDSO) vdso32=1: enable 32-bit VDSO (default) vdso32=0: disable 32-bit VDSO mapping |