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Documentation/kernel-parameters.txt
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Kernel Parameters ~~~~~~~~~~~~~~~~~ |
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The following is a consolidated list of the kernel parameters as implemented (mostly) by the __setup() macro 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. Module parameters for loadable modules are specified only as the parameter name with optional '=' and value as appropriate, such as: modprobe usbcore blinkenlights=1 Module parameters for modules that are built into the kernel image are specified on the kernel command line with the module name plus '.' plus parameter name, with '=' and value if appropriate, such as: usbcore.blinkenlights=1 |
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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 |
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This document may not be entirely up to date and comprehensive. The command "modinfo -p ${modulename}" shows a current list of all parameters of a loadable module. Loadable modules, after being loaded into the running kernel, also reveal their parameters in /sys/module/${modulename}/parameters/. Some of these parameters may be changed at runtime by the command "echo -n ${value} > /sys/module/${modulename}/parameters/${parm}". |
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The parameters listed below are only valid if certain kernel build options were enabled and if respective hardware is present. The text in square brackets at the beginning of each description states the restrictions within which a parameter is applicable: |
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ACPI ACPI support is enabled. |
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AGP AGP (Accelerated Graphics Port) is enabled. |
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ALSA ALSA sound support is enabled. APIC APIC support is enabled. APM Advanced Power Management support is enabled. |
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ARM ARM architecture is enabled. |
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AVR32 AVR32 architecture is enabled. |
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AX25 Appropriate AX.25 support is enabled. |
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BLACKFIN Blackfin architecture is enabled. |
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DRM Direct Rendering Management support is enabled. DYNAMIC_DEBUG Build in debug messages and enable them at runtime |
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EDD BIOS Enhanced Disk Drive Services (EDD) is enabled EFI EFI Partitioning (GPT) is enabled EIDE EIDE/ATAPI support is enabled. FB The frame buffer device is enabled. |
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FTRACE Function tracing enabled. |
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GCOV GCOV profiling is enabled. |
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HW Appropriate hardware is enabled. |
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IA-64 IA-64 architecture is enabled. |
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IMA Integrity measurement architecture is enabled. |
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IOSCHED More than one I/O scheduler is enabled. |
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IP_PNP IP DHCP, BOOTP, or RARP is enabled. |
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IPV6 IPv6 support is enabled. |
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ISAPNP ISA PnP code is enabled. ISDN Appropriate ISDN support is enabled. JOY Appropriate joystick support is enabled. |
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KGDB Kernel debugger support is enabled. |
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KVM Kernel Virtual Machine support is enabled. |
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LIBATA Libata driver is enabled |
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LP Printer support is enabled. LOOP Loopback device support is enabled. M68k M68k architecture is enabled. These options have more detailed description inside of Documentation/m68k/kernel-options.txt. MCA MCA bus support is enabled. MDA MDA console support is enabled. |
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MIPS MIPS architecture is enabled. |
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MOUSE Appropriate mouse support is enabled. |
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MSI Message Signaled Interrupts (PCI). |
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MTD MTD (Memory Technology Device) support is enabled. |
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NET Appropriate network support is enabled. NUMA NUMA support is enabled. NFS Appropriate NFS support is enabled. OSS OSS sound support is enabled. |
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PV_OPS A paravirtualized kernel is enabled. PARIDE The ParIDE (parallel port IDE) subsystem is enabled. |
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PARISC The PA-RISC architecture is enabled. PCI PCI bus support is enabled. |
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PCIE PCI Express support is enabled. |
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PCMCIA The PCMCIA subsystem is enabled. PNP Plug & Play support is enabled. PPC PowerPC architecture is enabled. PPT Parallel port support is enabled. PS2 Appropriate PS/2 support is enabled. RAM RAM disk support is enabled. S390 S390 architecture is enabled. SCSI Appropriate SCSI support is enabled. |
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A lot of drivers have their options described inside the Documentation/scsi/ sub-directory. |
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SECURITY Different security models are enabled. |
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SELINUX SELinux support is enabled. |
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APPARMOR AppArmor support is enabled. |
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SERIAL Serial support is enabled. |
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SH SuperH architecture is enabled. |
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SMP The kernel is an SMP kernel. SPARC Sparc architecture is enabled. |
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SWSUSP Software suspend (hibernation) is enabled. SUSPEND System suspend states are enabled. |
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TPM TPM drivers are enabled. |
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TS Appropriate touchscreen support is enabled. |
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UMS USB Mass Storage support is enabled. |
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USB USB support is enabled. USBHID USB Human Interface Device support is enabled. V4L Video For Linux support is enabled. VGA The VGA console has been enabled. VT Virtual terminal support is enabled. WDT Watchdog support is enabled. XT IBM PC/XT MFM hard disk support is enabled. |
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X86-32 X86-32, aka i386 architecture is enabled. |
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X86-64 X86-64 architecture is enabled. More X86-64 boot options can be found in |
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Documentation/x86/x86_64/boot-options.txt . |
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X86 Either 32-bit or 64-bit x86 (same as X86-32+X86-64) |
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XEN Xen support is enabled |
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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. BOOT Is a boot loader parameter. Parameters denoted with BOOT are actually interpreted by the boot loader, and have no meaning to the kernel directly. Do not modify the syntax of boot loader parameters without extreme |
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need or coordination with <Documentation/x86/boot.txt>. |
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There are also arch-specific kernel-parameters not documented here. |
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See for example <Documentation/x86/x86_64/boot-options.txt>. |
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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. |
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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. |
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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. |
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acpi= [HW,ACPI,X86] |
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Advanced Configuration and Power Interface |
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Format: { force | off | strict | noirq | rsdt } |
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force -- enable ACPI if default was off off -- disable ACPI if default was on noirq -- do not use ACPI for IRQ routing |
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strict -- Be less tolerant of platforms that are not |
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strictly ACPI specification compliant. |
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rsdt -- prefer RSDT over (default) XSDT |
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copy_dsdt -- copy DSDT to memory |
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See also Documentation/power/pm.txt, pci=noacpi |
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acpi_rsdp= [ACPI,EFI,KEXEC] Pass the RSDP address to the kernel, mostly used on machines running EFI runtime service to boot the second kernel for kdump. |
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acpi_apic_instance= [ACPI, IOAPIC] Format: <int> 2: use 2nd APIC table, if available 1,0: use 1st APIC table |
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default: 0 |
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acpi_backlight= [HW,ACPI] acpi_backlight=vendor acpi_backlight=video If set to vendor, prefer vendor specific driver (e.g. thinkpad_acpi, sony_acpi, etc.) instead of the ACPI video.ko driver. |
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acpi.debug_layer= [HW,ACPI,ACPI_DEBUG] acpi.debug_level= [HW,ACPI,ACPI_DEBUG] |
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Format: <int> |
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CONFIG_ACPI_DEBUG must be enabled to produce any ACPI debug output. Bits in debug_layer correspond to a _COMPONENT in an ACPI source file, e.g., #define _COMPONENT ACPI_PCI_COMPONENT Bits in debug_level correspond to a level in ACPI_DEBUG_PRINT statements, e.g., ACPI_DEBUG_PRINT((ACPI_DB_INFO, ... |
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The debug_level mask defaults to "info". See Documentation/acpi/debug.txt for more information about debug layers and levels. |
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Enable processor driver info messages: acpi.debug_layer=0x20000000 Enable PCI/PCI interrupt routing info messages: acpi.debug_layer=0x400000 |
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Enable AML "Debug" output, i.e., stores to the Debug object while interpreting AML: acpi.debug_layer=0xffffffff acpi.debug_level=0x2 |
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Enable all messages related to ACPI hardware: acpi.debug_layer=0x2 acpi.debug_level=0xffffffff Some values produce so much output that the system is unusable. The "log_buf_len" parameter may be useful if you need to capture more output. |
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acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs default in APIC mode acpi_irq_nobalance [HW,ACPI] ACPI will not move active IRQs (default) default in PIC mode acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA Format: <irq>,<irq>... acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for use by PCI Format: <irq>,<irq>... acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT 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] 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 |
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acpi_pm_good [X86] |
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Override the pmtimer bug detection: force the kernel to assume that this machine's pmtimer latches its value and always returns good values. |
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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, |
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old_ordering, nonvs, sci_force_enable } |
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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). |
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nonvs prevents the kernel from saving/restoring the ACPI NVS memory during suspend/hibernation and resume. |
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sci_force_enable causes the kernel to set SCI_EN directly on resume from S1/S3 (which is against the ACPI spec, but some broken systems don't work without it). |
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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 |
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acpi_enforce_resources= [ACPI] { strict | lax | no } Check for resource conflicts between native drivers and ACPI OperationRegions (SystemIO and SystemMemory only). IO ports and memory declared in ACPI might be used by the ACPI subsystem in arbitrary AML code and can interfere with legacy drivers. strict (default): access to resources claimed by ACPI is denied; legacy drivers trying to access reserved resources will fail to bind to device using them. lax: access to resources claimed by ACPI is allowed; legacy drivers trying to access reserved resources will bind successfully but a warning message is logged. no: ACPI OperationRegions are not marked as reserved, no further checks are performed. |
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add_efi_memmap [EFI; X86] Include EFI memory map in kernel's map of available physical RAM. |
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agp= [AGP] { off | try_unsupported } off: disable AGP support try_unsupported: try to drive unsupported chipsets (may crash computer or cause data corruption) |
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ALSA [HW,ALSA] See Documentation/sound/alsa/alsa-parameters.txt |
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alignment= [KNL,ARM] Allow the default userspace alignment fault handler behaviour to be specified. Bit 0 enables warnings, bit 1 enables fixups, and bit 2 sends a segfault. |
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amd_iommu= [HW,X86-84] Pass parameters to the AMD IOMMU driver in the system. Possible values are: |
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fullflush - enable flushing of IO/TLB entries when they are unmapped. Otherwise they are flushed before they will be reused, which is a lot of faster |
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off - do not initialize any AMD IOMMU found in the system |
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amijoy.map= [HW,JOY] Amiga joystick support Map of devices attached to JOY0DAT and JOY1DAT Format: <a>,<b> See also Documentation/kernel/input/joystick.txt analog.map= [HW,JOY] Analog joystick and gamepad support Specifies type or capabilities of an analog joystick connected to one of 16 gameports Format: <type1>,<type2>,..<type16> |
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apc= [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.) |
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Format: noidle Disable APC CPU standby support. SPARCstation-Fox does not play well with APC CPU idle - disable it if you have APC and your system crashes randomly. |
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apic= [APIC,X86-32] Advanced Programmable Interrupt Controller |
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Change the output verbosity whilst booting |
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Format: { quiet (default) | verbose | debug } Change the amount of debugging information output when initialising the APIC and IO-APIC components. |
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autoconf= [IPV6] See Documentation/networking/ipv6.txt. |
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show_lapic= [APIC,X86] Advanced Programmable Interrupt Controller Limit apic dumping. The parameter defines the maximal number of local apics being dumped. Also it is possible to set it to "all" by meaning -- no limit here. Format: { 1 (default) | 2 | ... | all }. The parameter valid if only apic=debug or apic=verbose is specified. Example: apic=debug show_lapic=all |
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apm= [APM] Advanced Power Management |
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See header of arch/x86/kernel/apm_32.c. |
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arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards Format: <io>,<irq>,<nodeID> ataflop= [HW,M68k] atarimouse= [HW,MOUSE] Atari Mouse |
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atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess, EzKey and similar keyboards atkbd.reset= [HW] Reset keyboard during initialization |
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atkbd.set= [HW] Select keyboard code set Format: <int> (2 = AT (default), 3 = PS/2) |
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atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar keyboards atkbd.softraw= [HW] Choose between synthetic and real raw mode Format: <bool> (0 = real, 1 = synthetic (default)) |
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atkbd.softrepeat= [HW] Use software keyboard repeat |
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autotest [IA-64] |
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baycom_epp= [HW,AX25] Format: <io>,<mode> |
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baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem Format: <io>,<mode> See header of drivers/net/hamradio/baycom_par.c. |
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baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode) |
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Format: <io>,<irq>,<mode>[,<baud>] See header of drivers/net/hamradio/baycom_ser_fdx.c. |
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baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode) |
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Format: <io>,<irq>,<mode> See header of drivers/net/hamradio/baycom_ser_hdx.c. |
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boot_delay= Milliseconds to delay each printk during boot. Values larger than 10 seconds (10000) are changed to no delay (0). Format: integer |
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bootmem_debug [KNL] Enable bootmem allocator debug messages. |
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bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards) |
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bttv.radio= Most important insmod options are available as kernel args too. |
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bttv.pll= See Documentation/video4linux/bttv/Insmod-options bttv.tuner= and Documentation/video4linux/bttv/CARDLIST |
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bulk_remove=off [PPC] This parameter disables the use of the pSeries firmware feature for flushing multiple hpte entries at a time. |
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c101= [NET] Moxa C101 synchronous serial card |
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cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection. |
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Sometimes CPU hardware bugs make them report the cache size incorrectly. The kernel will attempt work arounds to fix known problems, but for some CPUs it is not possible to determine what the correct size should be. This option provides an override for these situations. |
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capability.disable= [SECURITY] Disable capabilities. This would normally be used only if an alternative security model is to be configured. Potentially dangerous and should only be used if you are entirely sure of the consequences. |
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ccw_timeout_log [S390] See Documentation/s390/CommonIO for details. |
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cgroup_disable= [KNL] Disable a particular controller Format: {name of the controller(s) to disable} {Currently supported controllers - "memory"} |
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checkreqprot [SELINUX] Set initial checkreqprot flag value. Format: { "0" | "1" } See security/selinux/Kconfig help text. |
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0 -- check protection applied by kernel (includes any implied execute protection). |
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1 -- check protection requested by application. Default value is set via a kernel config option. |
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Value can be changed at runtime via /selinux/checkreqprot. |
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cio_ignore= [S390] See Documentation/s390/CommonIO for details. |
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clock= [BUGS=X86-32, HW] gettimeofday clocksource override. |
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[Deprecated] |
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Forces specified clocksource (if available) to be used |
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when calculating gettimeofday(). If specified |
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clocksource is not available, it defaults to PIT. |
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Format: { pit | tsc | cyclone | pmtmr } |
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clocksource= Override the default clocksource |
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Format: <string> Override the default clocksource and use the clocksource with the name specified. Some clocksource names to choose from, depending on the platform: [all] jiffies (this is the base, fallback clocksource) [ACPI] acpi_pm [ARM] imx_timer1,OSTS,netx_timer,mpu_timer2, pxa_timer,timer3,32k_counter,timer0_1 [AVR32] avr32 |
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[X86-32] pit,hpet,tsc; |
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scx200_hrt on Geode; cyclone on IBM x440 [MIPS] MIPS [PARISC] cr16 [S390] tod [SH] SuperH [SPARC64] tick [X86-64] hpet,tsc |
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clearcpuid=BITNUM [X86] Disable CPUID feature X for the kernel. See |
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arch/x86/include/asm/cpufeature.h for the valid bit numbers. Note the Linux specific bits are not necessarily |
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stable over kernel options, but the vendor specific ones should be. Also note that user programs calling CPUID directly or using the feature without checking anything will still see it. This just prevents it from being used by the kernel or shown in /proc/cpuinfo. Also note the kernel might malfunction if you disable some critical bits. |
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cmo_free_hint= [PPC] Format: { yes | no } Specify whether pages are marked as being inactive when they are freed. This is used in CMO environments to determine OS memory pressure for page stealing by a hypervisor. Default: yes |
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code_bytes [X86] How many bytes of object code to print |
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in an oops report. |
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Range: 0 - 8192 Default: 64 |
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com20020= [HW,NET] ARCnet - COM20020 chipset |
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Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]] |
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|
466 467 468 |
com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers) Format: <io>[,<irq>] |
a99130449
|
469 470 |
com90xx= [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers) |
1da177e4c
|
471 472 473 474 |
Format: <io>[,<irq>[,<memstart>]] condev= [HW,S390] console device conmode= |
a99130449
|
475 |
|
1da177e4c
|
476 477 478 479 480 |
console= [KNL] Output console device and options. tty<n> Use the virtual console device <n>. ttyS<n>[,options] |
f1a1c2dc2
|
481 |
ttyUSB0[,options] |
1da177e4c
|
482 |
Use the specified serial port. The options are of |
f1a1c2dc2
|
483 484 485 486 487 488 489 490 491 |
the form "bbbbpnf", where "bbbb" is the baud rate, "p" is parity ("n", "o", or "e"), "n" is number of bits, and "f" is flow control ("r" for RTS or omit it). Default is "9600n8". See Documentation/serial-console.txt for more information. See Documentation/networking/netconsole.txt for an alternative. |
1da177e4c
|
492 |
|
18a8bd949
|
493 494 |
uart[8250],io,<addr>[,options] uart[8250],mmio,<addr>[,options] |
1da177e4c
|
495 496 497 498 |
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. |
f7511d5f6
|
499 500 501 502 |
If the device connected to the port is not a TTY but a braille device, prepend "brl," before the device type, for instance console=brl,ttyS0 For now, only VisioBraille is supported. |
f324edc85
|
503 504 505 |
consoleblank= [KNL] The console blank (screen saver) timeout in seconds. Defaults to 10*60 = 10mins. A value of 0 disables the blank timer. |
4cb0e11b1
|
506 507 508 509 |
coredump_filter= [KNL] Change the default value for /proc/<pid>/coredump_filter. See also Documentation/filesystems/proc.txt. |
62027aea2
|
510 511 |
cpuidle.off=1 [CPU_IDLE] disable the cpuidle sub-system |
1da177e4c
|
512 |
cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver |
a99130449
|
513 514 |
Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] |
1da177e4c
|
515 |
|
6f21e6463
|
516 517 518 519 520 521 522 |
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. |
dc009d924
|
523 |
|
fb391599f
|
524 525 526 527 528 |
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 |
6f21e6463
|
529 |
Documentation/kdump/kdump.txt for an example. |
fb391599f
|
530 |
|
1da177e4c
|
531 532 533 534 535 |
cs89x0_dma= [HW,NET] Format: <dma> cs89x0_media= [HW,NET] Format: { rj45 | aui | bnc } |
a99130449
|
536 |
|
a99130449
|
537 |
dasd= [HW,NET] |
1da177e4c
|
538 539 540 541 542 543 |
See header of drivers/s390/block/dasd_devmap.c. db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port (one device per port) Format: <port#>,<type> See also Documentation/input/joystick-parport.txt |
a648ec05b
|
544 545 546 |
ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot time. See Documentation/dynamic-debug-howto.txt for details. |
1da177e4c
|
547 |
debug [KNL] Enable kernel debugging (events log level). |
cae2ed9aa
|
548 549 550 551 552 553 554 555 |
debug_locks_verbose= [KNL] verbose self-tests Format=<0|1> Print debugging info while doing the locking API self-tests. We default to 0 (no extra messages), setting it to 1 will print _a lot_ more information - normally only useful to kernel developers. |
3ac7fe5a4
|
556 |
debug_objects [KNL] Enable object debugging |
3e8ebb5c4
|
557 558 |
no_debug_objects [KNL] Disable object debugging |
d3af01f18
|
559 |
debugpat [X86] Enable PAT debugging |
2d27a9661
|
560 |
decnet.addr= [HW,NET] |
1da177e4c
|
561 562 |
Format: <area>[,<node>] See also Documentation/networking/decnet.txt. |
0cb55ad2a
|
563 564 565 566 567 568 569 |
default_hugepagesz= [same as hugepagesz=] The size of the default HugeTLB page size. This is the size represented by the legacy /proc/ hugepages APIs, used for SHM, and default size when mounting hugetlbfs filesystems. Defaults to the default architecture's huge page size if not specified. |
55ff9780e
|
570 |
|
1da177e4c
|
571 572 |
dhash_entries= [KNL] Set number of hash buckets for dentry cache. |
a99130449
|
573 |
|
1da177e4c
|
574 575 576 577 578 |
digi= [HW,SERIAL] IO parameters + enable/disable command. digiepca= [HW,SERIAL] See drivers/char/README.epca and |
31c00fc15
|
579 |
Documentation/serial/digiepca.txt. |
1da177e4c
|
580 |
|
b0f83b280
|
581 582 |
disable= [IPV6] See Documentation/networking/ipv6.txt. |
4e8b0cf46
|
583 584 585 |
disable_ddw [PPC/PSERIES] Disable Dynamic DMA Window support. Use this if to workaround buggy firmware. |
b0f83b280
|
586 587 |
disable_ipv6= [IPV6] See Documentation/networking/ipv6.txt. |
95ffa2438
|
588 |
disable_mtrr_cleanup [X86] |
95ffa2438
|
589 590 |
The kernel tries to adjust MTRR layout from continuous to discrete, to make X server driver able to add WB |
0cb55ad2a
|
591 |
entry later. This parameter disables that. |
95ffa2438
|
592 |
|
093af8d7f
|
593 |
disable_mtrr_trim [X86, Intel and AMD only] |
99fc8d424
|
594 595 596 597 |
By default the kernel will trim any uncacheable memory out of your available memory pool based on MTRR settings. This parameter disables that behavior, possibly causing your machine to run very slowly. |
6cececfce
|
598 |
disable_timer_pin_1 [X86] |
0cb55ad2a
|
599 600 |
Disable PIN 1 of APIC timer Can be useful to work around chipset bugs. |
0cb55ad2a
|
601 602 603 604 605 606 607 608 609 |
dma_debug=off If the kernel is compiled with DMA_API_DEBUG support, this option disables the debugging code at boot. dma_debug_entries=<number> This option allows to tune the number of preallocated entries for DMA-API debugging code. One entry is required per DMA-API allocation. Use this if the DMA-API debugging code disables itself because the architectural default is too low. |
1745de5e5
|
610 611 612 613 614 615 |
dma_debug_driver=<driver_name> With this option the DMA-API debugging driver filter feature can be enabled at boot time. Just pass the driver to filter for as the parameter. The filter can be disabled or changed to another driver later using sysfs. |
1da177e4c
|
616 |
dscc4.setup= [NET] |
0cb55ad2a
|
617 618 619 |
earlycon= [KNL] Output early console device and options. uart[8250],io,<addr>[,options] uart[8250],mmio,<addr>[,options] |
1917ac76e
|
620 |
uart[8250],mmio32,<addr>[,options] |
0cb55ad2a
|
621 622 |
Start an early, polled-mode console on the 8250/16550 UART at the specified I/O port or MMIO address. |
162902466
|
623 624 |
MMIO inter-register address stride is either 8-bit (mmio) or 32-bit (mmio32). |
0cb55ad2a
|
625 |
The options are the same as for ttyS, above. |
6cececfce
|
626 |
earlyprintk= [X86,SH,BLACKFIN] |
1da177e4c
|
627 628 |
earlyprintk=vga earlyprintk=serial[,ttySn[,baudrate]] |
ea3acb199
|
629 |
earlyprintk=ttySn[,baudrate] |
9780bc41d
|
630 |
earlyprintk=dbgp[debugController#] |
1da177e4c
|
631 |
|
a99130449
|
632 |
Append ",keep" to not disable it when the real console |
1da177e4c
|
633 |
takes over. |
5c05917e7
|
634 |
Only vga or serial or usb debug port at a time. |
1da177e4c
|
635 636 637 638 639 640 641 642 |
Currently only ttyS0 and ttyS1 are supported. Interaction with the standard serial driver is not very good. The VGA output is eventually overwritten by the real console. |
9731191f7
|
643 644 |
ekgdboc= [X86,KGDB] Allow early kernel console debugging ekgdboc=kbd |
25985edce
|
645 |
This is designed to be used in conjunction with |
9731191f7
|
646 |
the boot argument: earlyprintk=vga |
1da177e4c
|
647 |
edd= [EDD] |
8c4dd6068
|
648 |
Format: {"off" | "on" | "skip[mbr]"} |
1da177e4c
|
649 |
|
1da177e4c
|
650 651 |
eisa_irq_edge= [PARISC,HW] See header of drivers/parisc/eisa.c. |
cd4f0ef7c
|
652 |
elanfreq= [X86-32] |
1da177e4c
|
653 |
See comment before function elanfreq_setup() in |
71f77055d
|
654 |
arch/x86/kernel/cpu/cpufreq/elanfreq.c. |
1da177e4c
|
655 656 |
elevator= [IOSCHED] |
17a9e7bba
|
657 |
Format: {"cfq" | "deadline" | "noop"} |
a99130449
|
658 659 |
See Documentation/block/as-iosched.txt and Documentation/block/deadline-iosched.txt for details. |
162902466
|
660 |
elfcorehdr= [IA-64,PPC,SH,X86] |
a99130449
|
661 |
Specifies physical address of start of kernel core |
aac04b32f
|
662 663 664 |
image elf header. Generally kexec loader will pass this option to capture kernel. See Documentation/kdump/kdump.txt for details. |
1da177e4c
|
665 |
|
0cb55ad2a
|
666 667 668 669 |
enable_mtrr_cleanup [X86] The kernel tries to adjust MTRR layout from continuous to discrete, to make X server driver able to add WB entry later. This parameter enables that. |
ca1eda2d7
|
670 |
enable_timer_pin_1 [X86] |
0cb55ad2a
|
671 672 673 674 |
Enable PIN 1 of APIC timer Can be useful to work around chipset bugs (in particular on some ATI chipsets). The kernel tries to set a reasonable default. |
1da177e4c
|
675 676 677 678 679 680 681 |
enforcing [SELINUX] Set initial enforcing status. Format: {"0" | "1"} See security/selinux/Kconfig help text. 0 -- permissive (log only, no denials). 1 -- enforcing (deny and log). Default value is 0. Value can be changed at runtime via /selinux/enforce. |
a08f82d08
|
682 683 684 |
erst_disable [ACPI] Disable Error Record Serialization Table (ERST) support. |
1da177e4c
|
685 686 687 |
ether= [HW,NET] Ethernet cards parameters This option is obsoleted by the "netdev=" option, which has equivalent usage. See its documentation for details. |
de1ba09b2
|
688 689 690 691 692 693 |
failslab= fail_page_alloc= fail_make_request=[KNL] General fault injection mechanism. Format: <interval>,<probability>,<space>,<times> See also /Documentation/fault-injection/. |
1da177e4c
|
694 |
floppy= [HW] |
31c00fc15
|
695 |
See Documentation/blockdev/floppy.txt. |
1da177e4c
|
696 |
|
f13ae30e1
|
697 698 699 700 701 |
force_pal_cache_flush [IA-64] Avoid check_sal_cache_flush which may hang on buggy SAL_CACHE_FLUSH implementations. Using this parameter will force ia64_sal_cache_flush to call ia64_pal_cache_flush instead of SAL_CACHE_FLUSH. |
d9e540762
|
702 |
ftrace=[tracer] |
2af15d6a4
|
703 |
[FTRACE] will set and start the specified tracer |
d9e540762
|
704 705 |
as early as possible in order to facilitate early boot debugging. |
cecbca96d
|
706 |
ftrace_dump_on_oops[=orig_cpu] |
2af15d6a4
|
707 |
[FTRACE] will dump the trace buffers on oops. |
cecbca96d
|
708 709 710 711 |
If no parameter is passed, ftrace will dump buffers of all CPUs, but if you pass orig_cpu, it will dump only the buffer of the CPU that triggered the oops. |
2af15d6a4
|
712 713 714 715 716 717 |
ftrace_filter=[function-list] [FTRACE] Limit the functions traced by the function tracer at boot up. function-list is a comma separated list of functions. This list can be changed at run time by the set_ftrace_filter file in the debugfs |
162902466
|
718 |
tracing directory. |
2af15d6a4
|
719 720 721 722 723 724 |
ftrace_notrace=[function-list] [FTRACE] Do not trace the functions specified in function-list. This list can be changed at run time by the set_ftrace_notrace file in the debugfs tracing directory. |
d9e540762
|
725 |
|
369bc18f9
|
726 727 728 729 730 731 |
ftrace_graph_filter=[function-list] [FTRACE] Limit the top level callers functions traced by the function graph tracer at boot up. function-list is a comma separated list of functions that can be changed at run time by the set_graph_function file in the debugfs tracing directory. |
1da177e4c
|
732 733 734 735 736 737 738 |
gamecon.map[2|3]= [HW,JOY] Multisystem joystick and NES/SNES/PSX pad support via parallel port (up to 5 devices per port) Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5> See also Documentation/input/joystick-parport.txt gamma= [HW,DRM] |
aaf230424
|
739 740 741 |
gart_fix_e820= [X86_64] disable the fix e820 for K8 GART Format: off | on default: on |
2521f2c22
|
742 743 744 745 746 |
gcov_persist= [GCOV] When non-zero (default), profiling data for kernel modules is saved and remains accessible via debugfs, even when the module is unloaded/reloaded. When zero, profiling data is discarded and associated debugfs files are removed at module unload time. |
1da177e4c
|
747 748 |
gpt [EFI] Forces disk with valid GPT signature but invalid Protective MBR to be treated as GPT. |
1da177e4c
|
749 750 |
hashdist= [KNL,NUMA] Large hashes allocated during boot are distributed across NUMA nodes. Defaults on |
162902466
|
751 |
for 64-bit NUMA, off otherwise. |
a99130449
|
752 |
Format: 0 | 1 (for off | on) |
1da177e4c
|
753 754 755 756 757 |
hcl= [IA-64] SGI's Hardware Graph compatibility layer hd= [EIDE] (E)IDE hard drive subsystem geometry Format: <cyl>,<head>,<sect> |
ea8c071ca
|
758 759 760 761 |
hest_disable [ACPI] Disable Hardware Error Source Table (HEST) support; corresponding firmware-first mode error processing logic will be disabled. |
1da177e4c
|
762 763 764 765 |
highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact size of <nn>. This works even on boxes that have no highmem otherwise. This also works to reduce highmem size on bigger boxes. |
54cdfdb47
|
766 767 768 |
highres= [KNL] Enable/disable high resolution timer mode. Valid parameters: "on", "off" Default: "on" |
1da177e4c
|
769 770 |
hisax= [HW,ISDN] See Documentation/isdn/README.HiSax. |
0cb55ad2a
|
771 772 773 774 775 776 777 778 779 |
hlt [BUGS=ARM,SH] hpet= [X86-32,HPET] option to control HPET usage Format: { enable (default) | disable | force | verbose } disable: disable HPET and use PIT instead force: allow force enabled of undocumented chips (ICH4, VIA, nVidia) verbose: show contents of HPET registers during setup |
b4718e628
|
780 781 |
hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot. hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages. |
0d9ea7544
|
782 783 784 785 786 |
On x86-64 and powerpc, this option can be specified multiple times interleaved with hugepages= to reserve huge pages of different sizes. Valid pages sizes on x86-64 are 2M (when the CPU supports "pse") and 1G (when the CPU supports the "pdpe1gb" cpuinfo flag) |
b4718e628
|
787 788 |
Note that 1GB pages can only be allocated at boot time using hugepages= and not freed afterwards. |
6902aa84f
|
789 |
|
555d61d65
|
790 791 |
hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) terminal devices. Valid values: 0..8 |
431429ff7
|
792 793 794 |
hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs. If specified, z/VM IUCV HVC accepts connections from listed z/VM user IDs only. |
cef7125de
|
795 |
|
7bf693951
|
796 797 798 799 800 |
keep_bootcon [KNL] Do not unregister boot console at start. This is only useful for debugging when something happens in the window between unregistering the boot console and initializing the real console. |
3a853fb93
|
801 |
i2c_bus= [HW] Override the default board specific I2C bus speed |
7954763bb
|
802 803 |
or register an additional I2C bus that is not registered from board initialization code. |
3a853fb93
|
804 805 |
Format: <bus_id>,<clkrate> |
36d957392
|
806 |
i8042.debug [HW] Toggle i8042 debug mode |
1da177e4c
|
807 |
i8042.direct [HW] Put keyboard port into non-translated mode |
84eb8d060
|
808 809 |
i8042.dumbkbd [HW] Pretend that controller can only read data from keyboard and cannot control its state |
1da177e4c
|
810 811 |
(Don't attempt to blink the leds) i8042.noaux [HW] Don't check for auxiliary (== mouse) port |
945ef0d42
|
812 |
i8042.nokbd [HW] Don't check/create keyboard port |
75d08c789
|
813 814 |
i8042.noloop [HW] Disable the AUX Loopback command while probing for the AUX port |
1da177e4c
|
815 816 817 818 |
i8042.nomux [HW] Don't check presence of an active multiplexing controller i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX controllers |
f8313ef1f
|
819 |
i8042.notimeout [HW] Ignore timeout condition signalled by conroller |
1da177e4c
|
820 821 822 823 |
i8042.reset [HW] Reset the controller during init and cleanup i8042.unlock [HW] Unlock (ignore) the keylock i810= [HW,DRM] |
e70c9d5e6
|
824 825 826 |
i8k.ignore_dmi [HW] Continue probing hardware even if DMI data indicates that the driver is running on unsupported hardware. |
1da177e4c
|
827 828 829 830 831 832 833 |
i8k.force [HW] Activate i8k driver even if SMM BIOS signature does not match list of supported models. i8k.power_status [HW] Report power status in /proc/i8k (disabled by default) i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN capability is set. |
1da177e4c
|
834 835 |
icn= [HW,ISDN] Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]] |
0af80c04e
|
836 837 |
ide-core.nodma= [HW] (E)IDE subsystem Format: =0.0 to prevent dma on hda, =0.1 hdb =1.0 hdc |
075affcbe
|
838 839 |
.vlb_clock .pci_clock .noflush .nohpa .noprobe .nowerr .cdrom .chs .ignore_cable are additional options |
1c10e9382
|
840 |
See Documentation/ide/ide.txt. |
1da177e4c
|
841 |
|
0cb55ad2a
|
842 843 |
ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem Claim all unknown PCI IDE storage controllers. |
f039b7547
|
844 |
idle= [X86] |
ada9cfdd1
|
845 846 847 848 849 850 851 852 853 854 855 |
Format: idle=poll, idle=mwait, idle=halt, idle=nomwait Poll forces a polling idle loop that can slightly improve the performance of waking up a idle CPU, but will use a lot of power and make the system run hot. Not recommended. idle=mwait: On systems which support MONITOR/MWAIT but the kernel chose to not use it because it doesn't save as much power as a normal idle loop, use the MONITOR/MWAIT idle loop anyways. Performance should be the same as idle=poll. idle=halt: Halt is forced to be used for CPU idle. |
c1e3b377a
|
856 |
In such case C2/C3 won't be used again. |
ada9cfdd1
|
857 |
idle=nomwait: Disable mwait for CPU C-states |
a99130449
|
858 |
|
792908225
|
859 860 861 |
ignore_loglevel [KNL] Ignore loglevel setting - this will print /all/ kernel messages to the console. Useful for debugging. |
1da177e4c
|
862 863 |
ihash_entries= [KNL] Set number of hash buckets for inode cache. |
3323eec92
|
864 865 866 867 868 869 |
ima_audit= [IMA] Format: { "0" | "1" } 0 -- integrity auditing messages. (Default) 1 -- enable informational integrity auditing messages. ima_hash= [IMA] |
a9ed83a58
|
870 |
Format: { "sha1" | "md5" } |
3323eec92
|
871 |
default: "sha1" |
5789ba3bd
|
872 873 874 875 876 |
ima_tcb [IMA] Load a policy which meets the needs of the Trusted Computing Base. This means IMA will measure all programs exec'd, files mmap'd for exec, and all files opened for read by uid=0. |
1da177e4c
|
877 878 879 880 881 882 883 884 885 886 887 888 889 |
init= [KNL] Format: <full_path> Run specified binary instead of /sbin/init as init process. initcall_debug [KNL] Trace initcalls as they are executed. Useful for working out where the kernel is dying during startup. initrd= [BOOT] Specify the location of the initial ramdisk inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver Format: <irq> |
ba3959276
|
890 |
intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option |
0cd5c3c80
|
891 892 |
on Enable intel iommu driver. |
ba3959276
|
893 894 895 896 897 898 899 900 |
off Disable intel iommu driver. igfx_off [Default Off] By default, gfx is mapped as normal device. If a gfx device has a dedicated DMAR unit, the DMAR unit is bypassed by not enabling DMAR with this option. In this case, gfx device will use physical address for DMA. |
7d3b03ce7
|
901 902 |
forcedac [x86_64] With this option iommu will not optimize to look |
162902466
|
903 |
for io virtual address below 32-bit forcing dual |
7d3b03ce7
|
904 |
address cycle on pci bus for cards supporting greater |
162902466
|
905 906 |
than 32-bit addressing. The default is to look for translation below 32-bit and if not available |
7d3b03ce7
|
907 |
then look in the higher range. |
5e0d2a6fc
|
908 909 910 911 |
strict [Default Off] With this option on every unmap_single operation will result in a hardware IOTLB flush operation as opposed to batching them for performance. |
6dd9a7c73
|
912 913 914 915 |
sp_off [Default Off] By default, super page will be supported if Intel IOMMU has the capability. With this option, super page will not be supported. |
d1423d567
|
916 917 918 919 920 |
intremap= [X86-64, Intel-IOMMU] Format: { on (default) | off | nosid } on enable Interrupt Remapping (default) off disable Interrupt Remapping nosid disable Source ID checking |
162902466
|
921 |
inttest= [IA-64] |
0cb55ad2a
|
922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 |
iomem= Disable strict checking of access to MMIO memory strict regions from userspace. relaxed iommu= [x86] off force noforce biomerge panic nopanic merge nomerge forcesac soft |
162902466
|
938 |
pt [x86, IA-64] |
0cb55ad2a
|
939 940 941 942 |
io7= [HW] IO7 for Marvel based alpha systems See comment before marvel_specify_io7 in arch/alpha/kernel/core_marvel.c. |
6cececfce
|
943 |
io_delay= [X86] I/O delay method |
6e7c40259
|
944 945 946 947 |
0x80 Standard port 0x80 based delay 0xed Alternate port 0xed based delay (needed on some systems) |
b02aae9cf
|
948 |
udelay |
6e7c40259
|
949 950 951 |
Simple two microseconds delay none No delay |
b02aae9cf
|
952 |
|
1da177e4c
|
953 |
ip= [IP_PNP] |
dc7a08166
|
954 |
See Documentation/filesystems/nfs/nfsroot.txt. |
1da177e4c
|
955 956 |
ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards |
c8facbb62
|
957 958 |
See comment before ip2_setup() in drivers/char/ip2/ip2base.c. |
1da177e4c
|
959 |
|
200803dfe
|
960 961 962 963 964 965 966 967 968 969 |
irqfixup [HW] When an interrupt is not handled search all handlers for it. Intended to get systems with badly broken firmware running. irqpoll [HW] When an interrupt is not handled search all handlers for it. Also check all handlers each timer interrupt. Intended to get systems with badly broken firmware running. |
1da177e4c
|
970 |
isapnp= [ISAPNP] |
a99130449
|
971 |
Format: <RDP>,<reset>,<pci_scan>,<verbosity> |
1da177e4c
|
972 973 |
isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler. |
22f2e2801
|
974 975 976 |
Format: <cpu number>,...,<cpu number> or |
b225d44e2
|
977 978 |
<cpu number>-<cpu number> (must be a positive range in ascending order) |
22f2e2801
|
979 980 |
or a mixture <cpu number>,...,<cpu number>-<cpu number> |
b225d44e2
|
981 |
|
1da177e4c
|
982 983 |
This option can be used to specify one or more CPUs to isolate from the general SMP balancing and scheduling |
b225d44e2
|
984 985 |
algorithms. You can move a process onto or off an "isolated" CPU via the CPU affinity syscalls or cpuset. |
1da177e4c
|
986 987 988 989 |
<cpu number> begins at 0 and the maximum value is "number of CPUs in system - 1". This option is the preferred way to isolate CPUs. The |
a99130449
|
990 991 992 |
alternative -- manually setting the CPU mask of all tasks in the system -- can cause problems and suboptimal load balancer performance. |
1da177e4c
|
993 |
|
a99130449
|
994 |
iucv= [HW,NET] |
1da177e4c
|
995 996 997 |
js= [HW,JOY] Analog joystick See Documentation/input/joystick.txt. |
0cb55ad2a
|
998 |
keepinitrd [HW,ARM] |
6cececfce
|
999 |
kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter |
ed7ed3651
|
1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 |
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. |
4fe1da4eb
|
1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 |
kgdbdbgp= [KGDB,HW] kgdb over EHCI usb debug port. Format: <Controller#>[,poll interval] The controller # is the number of the ehci usb debug port as it is probed via PCI. The poll interval is optional and is the number seconds in between each poll cycle to the debug port in case you need the functionality for interrupting the kernel with gdb or control-c on the dbgp connection. When not using this parameter you use sysrq-g to break into the kernel debugger. |
84c08fd61
|
1024 |
kgdboc= [KGDB,HW] kgdb over consoles. |
ada64e4c9
|
1025 1026 |
Requires a tty driver that supports console polling, or a supported polling keyboard driver (non-usb). |
65b5ac147
|
1027 1028 1029 1030 1031 1032 |
Serial only format: <serial_device>[,baud] keyboard only format: kbd keyboard and serial format: kbd,<serial_device>[,baud] Optional Kernel mode setting: kms, kbd format: kms,kbd kms, kbd and serial format: kms,kbd,<ser_dev>[,baud] |
6cdf6e06d
|
1033 |
|
84c08fd61
|
1034 1035 |
kgdbwait [KGDB] Stop kernel execution and enter the kernel debugger at the earliest opportunity. |
9bed90c6a
|
1036 1037 1038 |
kmac= [MIPS] korina ethernet MAC address. Configure the RouterBoard 532 series on-chip Ethernet adapter MAC address. |
04f70336c
|
1039 1040 1041 |
kmemleak= [KNL] Boot-time kmemleak enable/disable Valid arguments: on, off Default: on |
6cececfce
|
1042 |
kstack=N [X86] Print N words from the kernel stack |
0cb55ad2a
|
1043 |
in oops dumps. |
fef07aae9
|
1044 1045 1046 1047 1048 |
kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs. Default is 0 (don't ignore, but inject #GP) kvm.oos_shadow= [KVM] Disable out-of-sync shadow paging. Default is 1 (enabled) |
a182d8737
|
1049 1050 |
kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit KVM MMU at runtime. |
fef07aae9
|
1051 |
Default is 0 (off) |
fef07aae9
|
1052 |
kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM. |
8475f94ab
|
1053 |
Default is 1 (enabled) |
fef07aae9
|
1054 1055 1056 |
kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU) for all guests. |
162902466
|
1057 |
Default is 1 (enabled) if in 64-bit or 32-bit PAE mode. |
fef07aae9
|
1058 |
|
fef07aae9
|
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 |
kvm-intel.ept= [KVM,Intel] Disable extended page tables (virtualized MMU) support on capable Intel chips. Default is 1 (enabled) kvm-intel.emulate_invalid_guest_state= [KVM,Intel] Enable emulation of invalid guest states Default is 0 (disabled) kvm-intel.flexpriority= [KVM,Intel] Disable FlexPriority feature (TPR shadow). Default is 1 (enabled) kvm-intel.unrestricted_guest= [KVM,Intel] Disable unrestricted guest feature (virtualized real and unpaged mode) on capable Intel chips. Default is 1 (enabled) kvm-intel.vpid= [KVM,Intel] Disable Virtual Processor Identification feature (tagged TLBs) on capable Intel chips. Default is 1 (enabled) |
1da177e4c
|
1079 |
l2cr= [PPC] |
a78bfbfcf
|
1080 |
l3cr= [PPC] |
cd4f0ef7c
|
1081 |
lapic [X86-32,APIC] Enable the local APIC even if BIOS |
a99130449
|
1082 |
disabled it. |
1da177e4c
|
1083 |
|
6cececfce
|
1084 |
lapic_timer_c2_ok [X86,APIC] trust the local apic timer |
ada9cfdd1
|
1085 |
in C2 power state. |
e585bef81
|
1086 |
|
fcb71f6f0
|
1087 1088 1089 1090 |
libata.dma= [LIBATA] DMA control libata.dma=0 Disable all PATA and SATA DMA libata.dma=1 PATA and SATA Disk DMA only libata.dma=2 ATAPI (CDROM) DMA only |
162902466
|
1091 |
libata.dma=4 Compact Flash DMA only |
fcb71f6f0
|
1092 1093 |
Combinations also work, so libata.dma=3 enables DMA for disks and CDROMs, but not CFs. |
162902466
|
1094 |
|
203088715
|
1095 1096 1097 |
libata.ignore_hpa= [LIBATA] Ignore HPA limit libata.ignore_hpa=0 keep BIOS limits (default) libata.ignore_hpa=1 ignore limits, using full disk |
fcb71f6f0
|
1098 |
|
78e70c237
|
1099 1100 1101 |
libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume when set. Format: <int> |
332673257
|
1102 1103 |
libata.force= [LIBATA] Force configurations. The format is comma separated list of "[ID:]VAL" where ID is |
4c44f309c
|
1104 |
PORT[.DEVICE]. PORT and DEVICE are decimal numbers |
332673257
|
1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 |
matching port, link or device. Basically, it matches the ATA ID string printed on console by libata. If the whole ID part is omitted, the last PORT and DEVICE values are used. If ID hasn't been specified yet, the configuration applies to all ports, links and devices. If only DEVICE is omitted, the parameter applies to the port and all links and devices behind it. DEVICE number of 0 either selects the first device or the first fan-out link behind PMP device. It does not select the host link. DEVICE number of 15 selects the host link and device attached to it. The VAL specifies the configuration to force. As long as there's no ambiguity shortcut notation is allowed. For example, both 1.5 and 1.5G would work for 1.5Gbps. The following configurations can be forced. * Cable type: 40c, 80c, short40c, unk, ign or sata. Any ID with matching PORT is used. * SATA link speed limit: 1.5Gbps or 3.0Gbps. * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7]. udma[/][16,25,33,44,66,100,133] notation is also allowed. * [no]ncq: Turn on or off NCQ. |
05944bdf6
|
1133 1134 |
* nohrst, nosrst, norst: suppress hard, soft and both resets. |
43c9c5918
|
1135 |
* dump_id: dump IDENTIFY data. |
332673257
|
1136 1137 |
If there are multiple matching configurations changing the same attribute, the last one is used. |
95f72d1ed
|
1138 |
memblock=debug [KNL] Enable memblock debug messages. |
7c4be253d
|
1139 |
|
1da177e4c
|
1140 |
load_ramdisk= [RAM] List of ramdisks to load from floppy |
31c00fc15
|
1141 |
See Documentation/blockdev/ramdisk.txt. |
1da177e4c
|
1142 |
|
a6b25b675
|
1143 1144 |
lockd.nlm_grace_period=P [NFS] Assign grace period. Format: <integer> |
1da177e4c
|
1145 |
|
a6b25b675
|
1146 1147 1148 1149 1150 1151 1152 1153 |
lockd.nlm_tcpport=N [NFS] Assign TCP port. Format: <integer> lockd.nlm_timeout=T [NFS] Assign timeout value. Format: <integer> lockd.nlm_udpport=M [NFS] Assign UDP port. Format: <integer> |
1da177e4c
|
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 |
logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver Format: <irq> loglevel= All Kernel Messages with a loglevel smaller than the console loglevel will be printed to the console. It can also be changed with klogd or other programs. The loglevels are defined as follows: 0 (KERN_EMERG) system is unusable 1 (KERN_ALERT) action must be taken immediately 2 (KERN_CRIT) critical conditions 3 (KERN_ERR) error conditions 4 (KERN_WARNING) warning conditions 5 (KERN_NOTICE) normal but significant condition 6 (KERN_INFO) informational 7 (KERN_DEBUG) debug-level messages |
c756d08a0
|
1171 1172 1173 |
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. |
1da177e4c
|
1174 |
|
accaa24c4
|
1175 1176 1177 1178 |
logo.nologo [FB] Disables display of the built-in Linux logo. This may be used to provide more screen space for kernel log messages and is useful when debugging kernel boot problems. |
1da177e4c
|
1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 |
lp=0 [LP] Specify parallel ports to use, e.g, lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses lp=reset first parallel port). 'lp=0' disables the lp=auto printer 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. See also header of drivers/char/lp.c. lpj=n [KNL] Sets loops_per_jiffy to given constant, thus avoiding time-consuming boot-time autodetection (up to 250 ms per CPU). 0 enables autodetection (default). To determine the correct value for your kernel, boot with normal autodetection and see what value is printed. Note that on SMP systems the preset will be applied to all CPUs, which is likely to cause problems if your CPUs need significantly divergent settings. An incorrect value will cause delays in the kernel to be wrong, leading to unpredictable I/O errors and other breakage. Although unlikely, in the extreme case this might damage your hardware. ltpc= [NET] Format: <io>,<irq>,<dma> |
162902466
|
1212 |
machvec= [IA-64] Force the use of a particular machine-vector |
a99130449
|
1213 1214 |
(machvec) in a generic kernel. Example: machvec=hpzx1_swiotlb |
1da177e4c
|
1215 |
|
3209e70e5
|
1216 1217 1218 |
machtype= [Loongson] Share the same kernel image file between different yeeloong laptop. Example: machtype=lemote-yeeloong-2f-7inch |
0cb55ad2a
|
1219 1220 |
max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater than or equal to this physical address is ignored. |
1da177e4c
|
1221 1222 |
maxcpus= [SMP] Maximum number of processors that an SMP kernel |
61ec7567d
|
1223 1224 1225 1226 |
should make use of. maxcpus=n : n >= 0 limits the kernel to using 'n' processors. n=0 is a special case, it is equivalent to "nosmp", which also disables the IO APIC. |
1da177e4c
|
1227 |
|
d134b00b9
|
1228 1229 1230 1231 1232 1233 |
max_loop= [LOOP] The number of loop block devices that get (loop.max_loop) unconditionally pre-created at init time. The default number is configured by BLK_DEV_LOOP_MIN_COUNT. Instead of statically allocating a predefined number, loop devices can be requested on-demand with the /dev/loop-control interface. |
2b2c37503
|
1234 |
|
1da177e4c
|
1235 |
mcatest= [IA-64] |
cd4f0ef7c
|
1236 |
mce [X86-32] Machine Check Exception |
1da177e4c
|
1237 |
|
71cced6eb
|
1238 |
mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt |
909dd324f
|
1239 |
|
1da177e4c
|
1240 1241 |
md= [HW] RAID subsystems devices and level See Documentation/md.txt. |
a99130449
|
1242 |
|
1da177e4c
|
1243 1244 1245 |
mdacon= [MDA] Format: <first>,<last> Specifies range of consoles to be captured by the MDA. |
a99130449
|
1246 |
|
1da177e4c
|
1247 1248 1249 |
mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory Amount of memory to be used when the kernel is not able to see the whole system memory or for test. |
cd4f0ef7c
|
1250 |
[X86-32] Use together with memmap= to avoid physical |
1da177e4c
|
1251 1252 |
address space collisions. Without memmap= PCI devices could be placed at addresses belonging to unused RAM. |
cd4f0ef7c
|
1253 |
mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel |
1da177e4c
|
1254 |
memory. |
6902aa84f
|
1255 1256 1257 |
memchunk=nn[KMG] [KNL,SH] Allow user to override the default size for per-device physically contiguous DMA buffers. |
6cececfce
|
1258 |
memmap=exactmap [KNL,X86] Enable setting of an exact |
1da177e4c
|
1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 |
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 option description. memmap=nn[KMG]@ss[KMG] [KNL] Force usage of a specific region of memory Region of memory to be used, from ss to ss+nn. memmap=nn[KMG]#ss[KMG] [KNL,ACPI] Mark specific memory as ACPI data. Region of memory to be used, from ss to ss+nn. memmap=nn[KMG]$ss[KMG] [KNL,ACPI] Mark specific memory as reserved. Region of memory to be used, from ss to ss+nn. |
1312848e9
|
1275 1276 1277 1278 |
Example: Exclude memory from 0x18690000-0x1869ffff memmap=64K$0x18690000 or memmap=0x10000$0x18690000 |
1da177e4c
|
1279 |
|
9f077871c
|
1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 |
memory_corruption_check=0/1 [X86] Some BIOSes seem to corrupt the first 64k of memory when doing things like suspend/resume. Setting this option will scan the memory looking for corruption. Enabling this will both detect corruption and prevent the kernel from using the memory being corrupted. However, its intended as a diagnostic tool; if repeatable BIOS-originated corruption always affects the same memory, you can use memmap= to prevent the kernel from using that memory. memory_corruption_check_size=size [X86] By default it checks for corruption in the low 64k, making this memory unavailable for normal use. Use this parameter to scan for corruption in more or less memory. memory_corruption_check_period=seconds [X86] By default it checks for corruption every 60 seconds. Use this parameter to check at some other rate. 0 disables periodic checking. |
caadbdce2
|
1302 |
memtest= [KNL,X86] Enable memtest |
c64df7079
|
1303 |
Format: <integer> |
c64df7079
|
1304 |
default : 0 <disable> |
9e5f6cf5f
|
1305 1306 1307 1308 1309 1310 |
Specifies the number of memtest passes to be performed. Each pass selects another test pattern from a given set of patterns. Memtest fills the memory with this pattern, validates memory contents and reserves bad memory regions that are detected. |
c64df7079
|
1311 |
|
1da177e4c
|
1312 1313 |
meye.*= [HW] Set MotionEye Camera parameters See Documentation/video4linux/meye.txt. |
8f36881b3
|
1314 1315 1316 |
mfgpt_irq= [IA-32] Specify the IRQ to use for the Multi-Function General Purpose Timers on AMD Geode platforms. |
e6c4dc6c3
|
1317 1318 1319 1320 |
mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when the BIOS has incorrectly applied a workaround. TinyBIOS version 0.98 is known to be affected, 0.99 fixes the problem by letting the user disable the workaround. |
1da177e4c
|
1321 |
mga= [HW,DRM] |
1c207f952
|
1322 1323 |
min_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory below this physical address is ignored. |
39f45d7bc
|
1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 |
mini2440= [ARM,HW,KNL] Format:[0..2][b][c][t] Default: "0tb" MINI2440 configuration specification: 0 - The attached screen is the 3.5" TFT 1 - The attached screen is the 7" TFT 2 - The VGA Shield is attached (1024x768) Leaving out the screen size parameter will not load the TFT driver, and the framebuffer will be left unconfigured. b - Enable backlight. The TFT backlight pin will be linked to the kernel VESA blanking code and a GPIO LED. This parameter is not necessary when using the VGA shield. c - Enable the s3c camera interface. t - Reserved for enabling touchscreen support. The touchscreen support is not enabled in the mainstream kernel as of 2.6.30, a preliminary port can be found in the "bleeding edge" mini2440 support kernel at http://repo.or.cz/w/linux-2.6/mini2440.git |
6b74ab97b
|
1344 1345 1346 1347 1348 1349 1350 |
mminit_loglevel= [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this parameter allows control of the logging verbosity for the additional memory initialisation checks. A value of 0 disables mminit logging and a level of 4 will log everything. Information is printed at KERN_DEBUG so loglevel=8 may also need to be specified. |
1da177e4c
|
1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 |
mousedev.tap_time= [MOUSE] Maximum time between finger touching and leaving touchpad surface for touch to be considered a tap and be reported as a left button click (for touchpads working in absolute mode only). Format: <msecs> mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices reporting absolute coordinates, such as tablets mousedev.yres= [MOUSE] Vertical screen resolution, used for devices reporting absolute coordinates, such as tablets |
6cececfce
|
1361 |
movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter |
0cb55ad2a
|
1362 1363 1364 1365 1366 1367 1368 1369 |
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. |
1da177e4c
|
1370 1371 |
MTD_Partition= [MTD] Format: <name>,<region-number>,<size>,<offset> |
a99130449
|
1372 1373 |
MTD_Region= [MTD] Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>] |
1da177e4c
|
1374 1375 |
mtdparts= [MTD] |
c8facbb62
|
1376 |
See drivers/mtd/cmdlinepart.c. |
1da177e4c
|
1377 |
|
4e89a2d8e
|
1378 1379 1380 |
multitce=off [PPC] This parameter disables the use of the pSeries firmware feature for updating multiple TCE entries at a time. |
5988af231
|
1381 1382 1383 1384 1385 1386 1387 1388 1389 |
onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration Format: [die0_boundary][,die0_lock][,die1_boundary][,die1_lock] boundary - index of last SLC block on Flex-OneNAND. The remaining blocks are configured as MLC blocks. lock - Configure if Flex-OneNAND boundary should be locked. Once locked, the boundary cannot be changed. 1 indicates lock status, 0 indicates unlock status. |
9db829f48
|
1390 1391 1392 1393 |
mtdset= [ARM] ARM/S3C2412 JIVE boot control See arch/arm/mach-s3c2412/mach-jive.c |
1da177e4c
|
1394 |
mtouchusb.raw_coordinates= |
a99130449
|
1395 1396 |
[HW] Make the MicroTouch USB driver use raw coordinates ('y', default) or cooked coordinates ('n') |
1da177e4c
|
1397 |
|
0cb55ad2a
|
1398 |
mtrr_chunk_size=nn[KMG] [X86] |
19f594600
|
1399 |
used for mtrr cleanup. It is largest continuous chunk |
0cb55ad2a
|
1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 |
that could hold holes aka. UC entries. mtrr_gran_size=nn[KMG] [X86] Used for mtrr cleanup. It is granularity of mtrr block. Default is 1. Large value could prevent small alignment from using up MTRRs. mtrr_spare_reg_nr=n [X86] Format: <integer> Range: 0,7 : spare reg number Default : 1 Used for mtrr cleanup. It is spare mtrr entries number. Set to 2 or more if your graphical card needs more. |
1da177e4c
|
1414 |
n2= [NET] SDL Inc. RISCom/N2 synchronous serial card |
1da177e4c
|
1415 1416 1417 1418 |
netdev= [NET] Network devices parameters Format: <irq>,<io>,<mem_start>,<mem_end>,<name> Note that mem_start is often overloaded to mean something different and driver-specific. |
a99130449
|
1419 1420 |
This usage is only documented in each driver source file if at all. |
584015727
|
1421 1422 1423 1424 |
nf_conntrack.acct= [NETFILTER] Enable connection tracking flow accounting 0 to disable accounting 1 to enable accounting |
d70a011db
|
1425 |
Default value is 0. |
584015727
|
1426 |
|
306a07536
|
1427 |
nfsaddrs= [NFS] Deprecated. Use ip= instead. |
dc7a08166
|
1428 |
See Documentation/filesystems/nfs/nfsroot.txt. |
1da177e4c
|
1429 1430 |
nfsroot= [NFS] nfs root filesystem for disk-less boxes. |
dc7a08166
|
1431 |
See Documentation/filesystems/nfs/nfsroot.txt. |
1da177e4c
|
1432 |
|
306a07536
|
1433 1434 |
nfsrootdebug [NFS] enable nfsroot debugging messages. See Documentation/filesystems/nfs/nfsroot.txt. |
a72b44222
|
1435 1436 1437 |
nfs.callback_tcpport= [NFS] set the TCP port on which the NFSv4 callback channel should listen. |
e571cbf1a
|
1438 1439 1440 1441 1442 1443 1444 |
nfs.cache_getent= [NFS] sets the pathname to the program which is used to update the NFS client cache entries. nfs.cache_getent_timeout= [NFS] sets the timeout after which an attempt to update a cache entry is deemed to have failed. |
58df095b7
|
1445 1446 1447 |
nfs.idmap_cache_timeout= [NFS] set the maximum lifetime for idmapper cache entries. |
f43bf0beb
|
1448 1449 1450 1451 1452 1453 |
nfs.enable_ino64= [NFS] enable 64-bit inode numbers. If zero, the NFS client will fake up a 32-bit inode number for the readdir() and stat() syscalls instead of returning the full 64-bit number. The default is to return 64-bit inode numbers. |
b064eca2c
|
1454 1455 1456 1457 1458 1459 1460 |
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. |
1e1030dcc
|
1461 |
nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take |
e7ba176b4
|
1462 1463 |
when a NMI is triggered. Format: [state][,regs][,debounce][,die] |
6cececfce
|
1464 |
nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels |
fef2c9bc1
|
1465 |
Format: [panic,][nopanic,][num] |
5dc305587
|
1466 |
Valid num: 0 |
5b9a0e14e
|
1467 |
0 - turn nmi_watchdog off |
0cb55ad2a
|
1468 |
When panic is specified, panic when an NMI watchdog |
fef2c9bc1
|
1469 1470 |
timeout occurs (or 'nopanic' to override the opposite default). |
0cb55ad2a
|
1471 1472 |
This is useful when you use a panic=... timeout and need the box quickly up again. |
1da177e4c
|
1473 |
|
bff38771e
|
1474 1475 1476 1477 |
netpoll.carrier_timeout= [NET] Specifies amount of time (in seconds) that netpoll should wait for a carrier. By default netpoll waits 4 seconds. |
cd4f0ef7c
|
1478 |
no387 [BUGS=X86-32] Tells the kernel to use the 387 maths |
1da177e4c
|
1479 1480 |
emulation library even if a 387 maths coprocessor is present. |
0cb55ad2a
|
1481 1482 1483 1484 1485 1486 1487 1488 1489 |
no_console_suspend [HW] Never suspend the console Disable suspending of consoles during suspend and hibernate operations. Once disabled, debugging messages can reach various consoles while the rest of the system is being put to sleep (ie, while debugging driver suspend/resume hooks). This may not work reliably with all consoles, but is known to work with serial and VGA consoles. |
c1aee215d
|
1490 1491 1492 |
noaliencache [MM, NUMA, SLAB] Disables the allocation of alien caches in the slab allocator. Saves per-node memory, but will impact performance. |
3395ee058
|
1493 |
|
a99130449
|
1494 |
noalign [KNL,ARM] |
1da177e4c
|
1495 1496 |
noapic [SMP,APIC] Tells the kernel to not make use of any IOAPICs that may be present in the system. |
5091faa44
|
1497 |
noautogroup Disable scheduler automatic task group creation. |
1da177e4c
|
1498 1499 1500 1501 |
nobats [PPC] Do not use BATs for mapping kernel lowmem on "Classic" PPC cores. nocache [ARM] |
a99130449
|
1502 |
|
0cb55ad2a
|
1503 |
noclflush [BUGS=X86] Don't use the CLFLUSH instruction |
163ecdff0
|
1504 |
nodelayacct [KNL] Disable per-task delay accounting |
1da177e4c
|
1505 |
nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects. |
6902aa84f
|
1506 |
nodsp [SH] Disable hardware DSP at boot time. |
6cececfce
|
1507 |
noefi [X86] Disable EFI runtime services support. |
8b2cb7a8f
|
1508 |
|
1da177e4c
|
1509 |
noexec [IA-64] |
6cececfce
|
1510 |
noexec [X86] |
f5a1b191b
|
1511 |
On X86-32 available only on PAE configured kernels. |
1da177e4c
|
1512 |
noexec=on: enable non-executable mappings (default) |
f5a1b191b
|
1513 |
noexec=off: disable non-executable mappings |
de5397ad5
|
1514 1515 1516 |
nosmep [X86] Disable SMEP (Supervisor Mode Execution Protection) even if it is supported by processor. |
f5a1b191b
|
1517 1518 1519 1520 1521 1522 |
noexec32 [X86-64] This affects only 32-bit executables. noexec32=on: enable non-executable mappings (default) read doesn't imply executable mappings noexec32=off: disable non-executable mappings read implies executable mappings |
1da177e4c
|
1523 |
|
6902aa84f
|
1524 |
nofpu [SH] Disable hardware FPU at boot time. |
cd4f0ef7c
|
1525 |
nofxsr [BUGS=X86-32] Disables x86 floating point extended |
4f8865112
|
1526 1527 |
register save and restore. The kernel will only save legacy floating-point registers on task switch. |
1da177e4c
|
1528 |
|
0c752a933
|
1529 1530 1531 |
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. |
01a24d2b9
|
1532 1533 1534 |
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. |
a99130449
|
1535 |
|
cd4f0ef7c
|
1536 |
no-hlt [BUGS=X86-32] Tells the kernel that the hlt |
1da177e4c
|
1537 1538 |
instruction doesn't work correctly and not to use it. |
1f29fae29
|
1539 1540 1541 |
no_file_caps Tells the kernel not to honor file capabilities. The only way then for a file to be executed with privilege is to be setuid root or executed by root. |
1da177e4c
|
1542 1543 1544 1545 1546 1547 |
nohalt [IA-64] Tells the kernel not to use the power saving function PAL_HALT_LIGHT when idle. This increases power-consumption. On the positive side, it reduces interrupt wake-up latency, which may improve performance in certain environments such as networked servers or real-time systems. |
79bf2bb33
|
1548 1549 1550 |
nohz= [KNL] Boottime enable/disable dynamic ticks Valid arguments: on, off Default: on |
eeee7853c
|
1551 |
noiotrap [SH] Disables trapped I/O port accesses. |
cd4f0ef7c
|
1552 |
noirqdebug [X86-32] Disables the code which attempts to detect and |
1da177e4c
|
1553 |
disable unhandled interrupt sources. |
6cececfce
|
1554 |
no_timer_check [X86,APIC] Disables the code which tests for |
8542b200c
|
1555 |
broken timer IRQ sources. |
1da177e4c
|
1556 1557 1558 1559 |
noisapnp [ISAPNP] Disables ISA PnP code. noinitrd [RAM] Tells the kernel not to load any configured initial RAM disk. |
03ea81550
|
1560 1561 |
nointremap [X86-64, Intel-IOMMU] Do not enable interrupt remapping. |
d1423d567
|
1562 |
[Deprecated - use intremap=off] |
03ea81550
|
1563 |
|
1da177e4c
|
1564 |
nointroute [IA-64] |
162902466
|
1565 |
nojitter [IA-64] Disables jitter checking for ITC timers. |
0aa366f35
|
1566 |
|
9cf4c4fcb
|
1567 |
no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver |
fd10cde92
|
1568 1569 |
no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page fault handling. |
d910f5c10
|
1570 1571 1572 |
no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. steal time is computed, but won't influence scheduler behaviour |
cd4f0ef7c
|
1573 |
nolapic [X86-32,APIC] Do not enable or use the local APIC. |
1da177e4c
|
1574 |
|
cd4f0ef7c
|
1575 |
nolapic_timer [X86-32,APIC] Do not use the local APIC timer. |
ad62ca2bd
|
1576 |
|
1da177e4c
|
1577 1578 |
noltlbs [PPC] Do not use large page/tlb entries for kernel lowmem mapping on PPC40x. |
312f1f014
|
1579 |
nomca [IA-64] Disable machine check abort handling |
cd4f0ef7c
|
1580 |
nomce [X86-32] Machine Check Exception |
abe37e5a1
|
1581 |
|
83d7384f8
|
1582 1583 |
nomfgpt [X86-32] Disable Multi-Function General Purpose Timer usage (for AMD Geode machines). |
016ddd9b5
|
1584 1585 |
nopat [X86] Disable PAT (page attribute table extension of pagetables) support. |
0cb55ad2a
|
1586 1587 |
norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space |
bbff2168c
|
1588 |
noreplace-paravirt [X86,IA-64,PV_OPS] Don't patch paravirt_ops |
959b4fdfe
|
1589 |
|
cd4f0ef7c
|
1590 |
noreplace-smp [X86-32,SMP] Don't replace SMP instructions |
b7fb4af06
|
1591 |
with UP alternatives |
1da177e4c
|
1592 |
noresidual [PPC] Don't use residual data on PReP machines. |
a99130449
|
1593 1594 |
noresume [SWSUSP] Disables resume and restores original swap space. |
1da177e4c
|
1595 1596 1597 1598 1599 |
no-scroll [VGA] Disables scrollback. This is required for the Braillex ib80-piezo Braille reader made by F.H. Papenmeier (Germany). nosbagart [IA-64] |
cd4f0ef7c
|
1600 |
nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support. |
4f8865112
|
1601 |
|
61ec7567d
|
1602 1603 |
nosmp [SMP] Tells an SMP kernel to act as a UP kernel, and disable the IO APIC. legacy for "maxcpus=0". |
1da177e4c
|
1604 |
|
97842216b
|
1605 |
nosoftlockup [KNL] Disable the soft-lockup detector. |
1da177e4c
|
1606 |
nosync [HW,M68K] Disables sync negotiation for all devices. |
cd4f0ef7c
|
1607 |
notsc [BUGS=X86-32] Disable Time Stamp Counter |
1da177e4c
|
1608 1609 |
nousb [USB] Disable the USB subsystem |
551423748
|
1610 |
nowatchdog [KNL] Disable the lockup detector (NMI watchdog). |
58687acba
|
1611 |
|
1da177e4c
|
1612 |
nowb [ARM] |
a99130449
|
1613 |
|
2b2fd87a6
|
1614 |
nox2apic [X86-64,APIC] Do not enable x2APIC mode. |
162902466
|
1615 |
nptcg= [IA-64] Override max number of concurrent global TLB |
a6c75b86c
|
1616 1617 |
purges which is reported from either PAL_VM_SUMMARY or SAL PALO. |
2b633e3fa
|
1618 1619 1620 1621 1622 |
nr_cpus= [SMP] Maximum number of processors that an SMP kernel could support. nr_cpus=n : n >= 1 limits the kernel to supporting 'n' processors. Later in runtime you can not use hotplug cpu feature to put more cpu back to online. just like you compile the kernel NR_CPUS=n |
0cb55ad2a
|
1623 |
nr_uarts= [SERIAL] maximum number of UARTs to be registered. |
f0c0b2b80
|
1624 1625 1626 1627 |
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. |
7c4be253d
|
1628 1629 1630 |
ohci1394_dma=early [HW] enable debugging via the ohci1394 driver. See Documentation/debugging-via-ohci1394.txt for more info. |
3ef0e1f8c
|
1631 1632 1633 1634 1635 1636 |
olpc_ec_timeout= [OLPC] ms delay when issuing EC commands Rather than timing out after 20 ms if an EC command is not properly ACKed, override the length of the timeout. We have interrupts disabled while waiting for the ACK, so if this is set too high interrupts *may* be lost! |
15ac7afe5
|
1637 1638 1639 1640 |
omap_mux= [OMAP] Override bootloader pin multiplexing. Format: <mux_mode0.mode_name=value>... For example, to override I2C bus2: omap_mux=i2c2_scl.i2c2_scl=0x100,i2c2_sda.i2c2_sda=0x100 |
1da177e4c
|
1641 1642 |
oprofile.timer= [HW] Use timer interrupt instead of performance counters |
7e4e0bd50
|
1643 1644 1645 |
oprofile.cpu_type= Force an oprofile cpu type This might be useful if you have an older oprofile userland or if you want common events. |
8d7ff4f2a
|
1646 1647 |
Format: { arch_perfmon } arch_perfmon: [X86] Force use of architectural |
7e4e0bd50
|
1648 1649 |
perfmon on Intel CPUs instead of the CPU specific event set. |
1dcdb5a9e
|
1650 |
|
44a4dcf75
|
1651 1652 1653 |
oops=panic Always panic on oopses. Default is to just kill the process, but there is a small probability of deadlocking the machine. |
d404ab0a1
|
1654 1655 |
This will also cause panics on machine check exceptions. Useful together with panic=30 to trigger a reboot. |
bcfde3347
|
1656 1657 |
OSS [HW,OSS] See Documentation/sound/oss/oss-parameters.txt |
44a4dcf75
|
1658 |
panic= [KNL] Kernel behaviour on panic: delay <timeout> |
4302fbc8e
|
1659 1660 1661 |
timeout > 0: seconds before rebooting timeout = 0: wait forever timeout < 0: reboot immediately |
1da177e4c
|
1662 1663 1664 1665 1666 1667 1668 |
Format: <timeout> parkbd.port= [HW] Parallel port number the keyboard adapter is connected to, default is 0. Format: <parport#> parkbd.mode= [HW] Parallel port keyboard adapter mode of operation, 0 for XT, 1 for AT (default is AT). |
a99130449
|
1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 |
Format: <mode> parport= [HW,PPT] Specify parallel ports. 0 disables. Format: { 0 | auto | 0xBBB[,IRQ[,DMA]] } Use 'auto' to force the driver 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. parport_init_mode= [HW,PPT] Configure VIA parallel port to operate in a specific mode. This is necessary on Pegasos computer where firmware has no options for setting up parallel port mode and sets it to spp. Currently this function knows 686a and 8231 chips. |
1da177e4c
|
1691 |
Format: [spp|ps2|epp|ecp|ecpepp] |
dd287796d
|
1692 1693 1694 1695 |
pause_on_oops= Halt all CPUs after the first oops has been printed for the specified number of seconds. This is to be used if your oopses keep scrolling off the screen. |
1da177e4c
|
1696 1697 1698 1699 |
pcbit= [HW,ISDN] pcd. [PARIDE] See header of drivers/block/paride/pcd.c. |
31c00fc15
|
1700 |
See also Documentation/blockdev/paride.txt. |
1da177e4c
|
1701 |
|
a99130449
|
1702 |
pci=option[,option...] [PCI] various PCI subsystem options: |
1cc0ca26c
|
1703 1704 |
earlydump [X86] dump PCI config space before the kernel changes anything |
c01156061
|
1705 |
off [X86] don't probe for the PCI bus |
cd4f0ef7c
|
1706 |
bios [X86-32] force use of PCI BIOS, don't access |
a99130449
|
1707 1708 |
the hardware directly. Use this if your machine has a non-standard PCI host bridge. |
cd4f0ef7c
|
1709 |
nobios [X86-32] disallow use of PCI BIOS, only direct |
a99130449
|
1710 1711 1712 |
hardware access methods are allowed. Use this if you experience crashes upon bootup and you suspect they are caused by the BIOS. |
c01156061
|
1713 |
conf1 [X86] Force use of PCI Configuration |
a99130449
|
1714 |
Mechanism 1. |
c01156061
|
1715 |
conf2 [X86] Force use of PCI Configuration |
a99130449
|
1716 |
Mechanism 2. |
7f7857636
|
1717 1718 1719 |
noaer [PCIE] If the PCIEAER kernel config parameter is enabled, this kernel boot option can be used to disable the use of PCIE advanced error reporting. |
32a2eea79
|
1720 1721 |
nodomains [PCI] Disable support for multiple PCI root domains (aka PCI segments, in ACPI-speak). |
6cececfce
|
1722 |
nommconf [X86] Disable use of MMCONFIG for PCI |
61be6d660
|
1723 |
Configuration |
129830773
|
1724 1725 1726 |
check_enable_amd_mmconf [X86] check for and enable properly configured MMIO access to PCI config space on AMD family 10h CPU |
309e57df7
|
1727 1728 1729 |
nomsi [MSI] If the PCI_MSI kernel config parameter is enabled, this kernel boot option can be used to disable the use of MSI interrupts system-wide. |
a9322f648
|
1730 1731 1732 |
noioapicquirk [APIC] Disable all boot interrupt quirks. Safety option to keep boot IRQs enabled. This should never be necessary. |
9197979b5
|
1733 1734 1735 1736 |
ioapicreroute [APIC] Enable rerouting of boot IRQs to the primary IO-APIC for bridges that cannot disable boot IRQs. This fixes a source of spurious IRQs when the system masks IRQs. |
41b9eb264
|
1737 1738 1739 1740 |
noioapicreroute [APIC] Disable workaround that uses the boot IRQ equivalent of an IRQ that connects to a chipset where boot IRQs cannot be disabled. The opposite of ioapicreroute. |
cd4f0ef7c
|
1741 |
biosirq [X86-32] Use PCI BIOS calls to get the interrupt |
a99130449
|
1742 1743 1744 1745 1746 1747 1748 |
routing table. These calls are known to be buggy on several machines and they hang the machine when used, but on other computers it's the only way to get the interrupt routing table. Try this option if the kernel is unable to allocate IRQs or discover secondary PCI buses on your motherboard. |
c01156061
|
1749 |
rom [X86] Assign address space to expansion ROMs. |
a99130449
|
1750 1751 1752 |
Use with caution as certain devices share address decoders between ROMs and other resources. |
c01156061
|
1753 |
norom [X86] Do not assign address space to |
bb71ad880
|
1754 1755 |
expansion ROMs that do not already have BIOS assigned address ranges. |
7bd1c365f
|
1756 1757 |
nobar [X86] Do not assign address space to the BARs that weren't assigned by the BIOS. |
c01156061
|
1758 |
irqmask=0xMMMM [X86] Set a bit mask of IRQs allowed to be |
a99130449
|
1759 1760 1761 |
assigned automatically to PCI devices. You can make the kernel exclude IRQs of your ISA cards this way. |
c01156061
|
1762 |
pirqaddr=0xAAAAA [X86] Specify the physical address |
a99130449
|
1763 1764 1765 |
of the PIRQ table (normally generated by the BIOS) if it is outside the F0000h-100000h range. |
c01156061
|
1766 |
lastbus=N [X86] Scan all buses thru bus #N. Can be |
a99130449
|
1767 1768 1769 |
useful if the kernel is unable to find your secondary buses and you want to tell it explicitly which ones they are. |
c01156061
|
1770 |
assign-busses [X86] Always assign all PCI bus |
a99130449
|
1771 1772 |
numbers ourselves, overriding whatever the firmware may have done. |
c01156061
|
1773 |
usepirqmask [X86] Honor the possible IRQ mask stored |
a99130449
|
1774 1775 1776 1777 1778 |
in the BIOS $PIR table. This is needed on some systems with broken BIOSes, notably some HP Pavilion N5400 and Omnibook XE3 notebooks. This will have no effect if ACPI IRQ routing is enabled. |
c01156061
|
1779 |
noacpi [X86] Do not use ACPI for IRQ routing |
a99130449
|
1780 |
or for PCI scanning. |
7bc5e3f2b
|
1781 1782 1783 1784 1785 1786 |
use_crs [X86] Use PCI host bridge window information from ACPI. On BIOSes from 2008 or later, this is enabled by default. If you need to use this, please report a bug. nocrs [X86] Ignore PCI host bridge windows from ACPI. If you need to use this, please report a bug. |
a99130449
|
1787 1788 1789 1790 |
routeirq Do IRQ routing for all PCI devices. This is normally done in pci_enable_device(), so this option is a temporary workaround for broken drivers that don't call it. |
13a6ddb08
|
1791 1792 |
skip_isa_align [X86] do not align io start addr, so can handle more pci cards |
a99130449
|
1793 1794 1795 1796 1797 |
firmware [ARM] Do not re-enumerate the bus but instead just use the configuration from the bootloader. This is currently used on IXP2000 systems where the bus has to be configured a certain way for adjunct CPUs. |
0637a70a5
|
1798 1799 1800 1801 1802 |
noearly [X86] Don't do any early type 1 scanning. This might help on some broken boards which machine check when some devices' config space is read. But various workarounds are disabled and some IOMMU drivers will not work. |
6b4b78fed
|
1803 1804 1805 1806 |
bfsort Sort PCI devices into breadth-first order. This sorting is done to get a device order compatible with older (<= 2.4) kernels. nobfsort Don't sort PCI devices into breadth-first order. |
4516a618a
|
1807 1808 1809 1810 1811 1812 |
cbiosize=nn[KMG] The fixed amount of bus space which is reserved for the CardBus bridge's IO window. The default value is 256 bytes. cbmemsize=nn[KMG] The fixed amount of bus space which is reserved for the CardBus bridge's memory window. The default value is 64 megabytes. |
32a9a682b
|
1813 1814 1815 1816 1817 1818 1819 1820 1821 |
resource_alignment= Format: [<order of align>@][<domain>:]<bus>:<slot>.<func>[; ...] Specifies alignment and device to reassign aligned memory resources. If <order of align> is not specified, PAGE_SIZE is used as alignment. PCI-PCI bridge can be specified, if resource windows need to be expanded. |
43c164088
|
1822 1823 1824 1825 1826 1827 |
ecrc= Enable/disable PCIe ECRC (transaction layer end-to-end CRC checking). bios: Use BIOS/firmware settings. This is the the default. off: Turn ECRC off on: Turn ECRC on. |
f483d3923
|
1828 1829 |
realloc reallocate PCI resources if allocations done by BIOS are erroneous. |
6b4b78fed
|
1830 |
|
e5665a45f
|
1831 1832 1833 1834 1835 |
pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power Management. off Disable ASPM. force Enable ASPM even on devices that claim not to support it. WARNING: Forcing ASPM on may cause system lockups. |
79dd9182d
|
1836 |
pcie_ports= [PCIE] PCIe ports handling: |
28eb5f274
|
1837 1838 1839 1840 1841 |
auto Ask the BIOS whether or not to use native PCIe services associated with PCIe ports (PME, hot-plug, AER). Use them only if that is allowed by the BIOS. native Use native PCIe services associated with PCIe ports unconditionally. |
79dd9182d
|
1842 1843 |
compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe ports driver. |
c7f486567
|
1844 |
pcie_pme= [PCIE,PM] Native PCIe PME signaling options: |
c39fae141
|
1845 |
nomsi Do not use MSI for native PCIe PME signaling (this makes |
28eb5f274
|
1846 |
all PCIe root ports use INTx for all services). |
c7f486567
|
1847 |
|
1da177e4c
|
1848 1849 1850 |
pcmv= [HW,PCMCIA] BadgePAD 4 pd. [PARIDE] |
31c00fc15
|
1851 |
See Documentation/blockdev/paride.txt. |
1da177e4c
|
1852 1853 1854 1855 1856 |
pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at boot time. Format: { 0 | 1 } See arch/parisc/kernel/pdc_chassis.c |
f58dc01ba
|
1857 |
percpu_alloc= Select which percpu first chunk allocator to use. |
e933a73f4
|
1858 1859 1860 1861 1862 |
Currently supported values are "embed" and "page". Archs may support subset or none of the selections. See comments in mm/percpu.c for details on each allocator. This parameter is primarily for debugging and performance comparison. |
fa8a7094b
|
1863 |
|
1da177e4c
|
1864 |
pf. [PARIDE] |
31c00fc15
|
1865 |
See Documentation/blockdev/paride.txt. |
1da177e4c
|
1866 1867 |
pg. [PARIDE] |
31c00fc15
|
1868 |
See Documentation/blockdev/paride.txt. |
1da177e4c
|
1869 1870 |
pirq= [SMP,APIC] Manual mp-table setup |
71cced6eb
|
1871 |
See Documentation/x86/i386/IO-APIC.txt. |
1da177e4c
|
1872 1873 1874 1875 |
plip= [PPT,NET] Parallel port network link Format: { parport<nr> | timid | 0 } See also Documentation/parport.txt. |
162902466
|
1876 |
pmtmr= [X86] Manual setup of pmtmr I/O Port. |
de32a2434
|
1877 1878 |
Override pmtimer IOPort with a hex value. e.g. pmtmr=0x508 |
96242116d
|
1879 1880 1881 1882 1883 1884 |
pnp.debug=1 [PNP] Enable PNP debug messages (depends on the CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time via /sys/module/pnp/parameters/debug. We always show current resource usage; turning this on also shows possible settings and some assignment information. |
97ef062bb
|
1885 |
|
1da177e4c
|
1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 |
pnpacpi= [ACPI] { off } pnpbios= [ISAPNP] { on | off | curr | res | no-curr | no-res } pnp_reserve_irq= [ISAPNP] Exclude IRQs for the autoconfiguration pnp_reserve_dma= [ISAPNP] Exclude DMAs for the autoconfiguration pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration |
a99130449
|
1899 |
Ranges are in pairs (I/O port base and size). |
1da177e4c
|
1900 1901 |
pnp_reserve_mem= |
a99130449
|
1902 1903 |
[ISAPNP] Exclude memory regions for the autoconfiguration. |
1da177e4c
|
1904 |
Ranges are in pairs (memory base and size). |
4af94f390
|
1905 1906 1907 1908 1909 |
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>.... |
45807a1df
|
1910 1911 |
print-fatal-signals= [KNL] debug: print fatal signals |
f84d49b21
|
1912 1913 1914 1915 1916 1917 1918 1919 |
If enabled, warn about various signal handling related application anomalies: too many signals, too many POSIX.1 timers, fatal signals causing a coredump - etc. If you hit the warning due to signal overflow, you might want to try "ulimit -i unlimited". |
45807a1df
|
1920 |
default: off. |
e84845c4b
|
1921 1922 |
printk.time= Show timing data prefixed to each printk message line Format: <bool> (1/Y/y=enable, 0/N/n=disable) |
0cb55ad2a
|
1923 1924 1925 1926 1927 1928 1929 |
processor.max_cstate= [HW,ACPI] Limit processor to maximum C-state max_cstate=9 overrides any DMI blacklist limit. processor.nocst [HW,ACPI] Ignore the _CST method to determine C-states, instead using the legacy FADT method |
1da177e4c
|
1930 |
profile= [KNL] Enable kernel profiling via /proc/profile |
a99130449
|
1931 1932 1933 1934 |
Format: [schedule,]<number> Param: "schedule" - profile schedule points. Param: <number> - step/bucket size as a power of 2 for statistical time based profiling. |
b3da2a73f
|
1935 1936 |
Param: "sleep" - profile D-state sleeping (millisecs). Requires CONFIG_SCHEDSTATS |
c0fe2e696
|
1937 |
Param: "kvm" - profile VM exits. |
1da177e4c
|
1938 |
|
1da177e4c
|
1939 1940 |
prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk before loading. |
31c00fc15
|
1941 |
See Documentation/blockdev/ramdisk.txt. |
1da177e4c
|
1942 |
|
a99130449
|
1943 1944 |
psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to probe for; one of (bare|imps|exps|lifebook|any). |
1da177e4c
|
1945 1946 |
psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports per second. |
a99130449
|
1947 1948 |
psmouse.resetafter= [HW,MOUSE] Try to reset the device after so many bad packets |
1da177e4c
|
1949 1950 1951 1952 |
(0 = never). psmouse.resolution= [HW,MOUSE] Set desired mouse resolution, in dpi. psmouse.smartscroll= |
a99130449
|
1953 |
[HW,MOUSE] Controls Logitech smartscroll autorepeat. |
1da177e4c
|
1954 |
0 = disabled, 1 = enabled (default). |
dee28e72b
|
1955 |
pstore.backend= Specify the name of the pstore backend to use |
1da177e4c
|
1956 |
pt. [PARIDE] |
31c00fc15
|
1957 |
See Documentation/blockdev/paride.txt. |
1da177e4c
|
1958 |
|
dc8c85871
|
1959 1960 1961 |
pty.legacy_count= [KNL] Number of legacy pty's. Overwrites compiled-in default number. |
7d2c502f1
|
1962 |
quiet [KNL] Disable most log messages |
a99130449
|
1963 |
|
1da177e4c
|
1964 1965 1966 1967 |
r128= [HW,DRM] raid= [HW,RAID] See Documentation/md.txt. |
a99130449
|
1968 |
ramdisk_blocksize= [RAM] |
31c00fc15
|
1969 |
See Documentation/blockdev/ramdisk.txt. |
a99130449
|
1970 |
|
1da177e4c
|
1971 |
ramdisk_size= [RAM] Sizes of RAM disks in kilobytes |
31c00fc15
|
1972 |
See Documentation/blockdev/ramdisk.txt. |
1da177e4c
|
1973 |
|
24aaef8d7
|
1974 1975 1976 |
rcupdate.blimit= [KNL,BOOT] Set maximum number of finished RCU callbacks to process in one batch. |
21a1ea9eb
|
1977 |
|
24aaef8d7
|
1978 1979 |
rcupdate.qhimark= [KNL,BOOT] Set threshold of queued |
21a1ea9eb
|
1980 |
RCU callbacks over which batch limiting is disabled. |
24aaef8d7
|
1981 1982 1983 |
rcupdate.qlowmark= [KNL,BOOT] Set threshold of queued RCU callbacks below which batch limiting is re-enabled. |
21a1ea9eb
|
1984 |
|
ffdfc4097
|
1985 1986 1987 1988 |
rdinit= [KNL] Format: <full_path> Run specified binary instead of /init from the ramdisk, used for early userspace startup. See initrd. |
cd4f0ef7c
|
1989 |
reboot= [BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode |
1da177e4c
|
1990 |
Format: <reboot_mode>[,<reboot_mode2>[,...]] |
ecb08d813
|
1991 |
See arch/*/kernel/reboot.c or arch/*/kernel/process.c |
1da177e4c
|
1992 |
|
46b6d94eb
|
1993 1994 |
relax_domain_level= [KNL, SMP] Set scheduler's default relax_domain_level. |
21acb9caa
|
1995 |
See Documentation/cgroups/cpusets.txt. |
46b6d94eb
|
1996 |
|
1da177e4c
|
1997 |
reserve= [KNL,BUGS] Force the kernel to ignore some iomem area |
cd4f0ef7c
|
1998 |
reservetop= [X86-32] |
461a9afff
|
1999 2000 2001 |
Format: nn[KMG] Reserves a hole at the top of the kernel virtual address space. |
9ea77bdb3
|
2002 2003 2004 2005 |
reservelow= [X86] Format: nn[K] Set the amount of memory to reserve for BIOS at the bottom of the address space. |
7e96287dd
|
2006 2007 |
reset_devices [KNL] Force drivers to reset the underlying device during initialization. |
a99130449
|
2008 2009 |
resume= [SWSUSP] Specify the partition device for software suspend |
1da177e4c
|
2010 |
|
ecbd0da1e
|
2011 2012 2013 2014 2015 |
resume_offset= [SWSUSP] Specify the offset from the beginning of the partition given by "resume=" at which the swap header is located, in <PAGE_SIZE> units (needed only for swap files). See Documentation/power/swsusp-and-swap-files.txt |
f996fc967
|
2016 2017 2018 2019 |
hibernate= [HIBERNATION] noresume Don't check if there's a hibernation image present during boot. nocompress Don't compress/decompress hibernation images. |
0a7b35cb1
|
2020 |
retain_initrd [RAM] Keep initrd memory after extraction |
1da177e4c
|
2021 2022 2023 2024 2025 2026 2027 2028 2029 |
rhash_entries= [KNL,NET] Set number of hash buckets for route cache riscom8= [HW,SERIAL] Format: <io_board1>[,<io_board2>[,...<io_boardN>]] ro [KNL] Mount root device read-only on boot root= [KNL] Root filesystem |
f2d34fd94
|
2030 |
See name_to_dev_t comment in init/do_mounts.c. |
1da177e4c
|
2031 2032 2033 2034 2035 2036 2037 |
rootdelay= [KNL] Delay (in seconds) to pause before attempting to mount the root filesystem rootflags= [KNL] Set root filesystem mount option string rootfstype= [KNL] Set root filesystem type |
cc1ed7542
|
2038 2039 2040 |
rootwait [KNL] Wait (indefinitely) for root device to show up. Useful for devices that are detected asynchronously (e.g. USB and MMC devices). |
1da177e4c
|
2041 2042 2043 2044 2045 2046 |
rw [KNL] Mount root device read-write on boot S [KNL] Run init in single mode sa1100ir [NET] See drivers/net/irda/sa1100_ir.c. |
1da177e4c
|
2047 |
sbni= [NET] Granch SBNI12 leased line adapter |
a99130449
|
2048 |
|
f6630114d
|
2049 |
sched_debug [KNL] Enables verbose scheduler debug messages. |
0cb55ad2a
|
2050 2051 2052 2053 2054 2055 2056 |
security= [SECURITY] Choose a security module to enable at boot. If this boot parameter is not specified, only the first security module asking for security registration will be loaded. An invalid security module name will be treated as if no module has been chosen. selinux= [SELINUX] Disable or enable SELinux at boot time. |
1da177e4c
|
2057 2058 2059 2060 2061 2062 2063 |
Format: { "0" | "1" } See security/selinux/Kconfig help text. 0 -- disable. 1 -- enable. Default value is set via kernel config option. If enabled at boot time, /selinux/disable can be used later to disable prior to initial policy load. |
c1c124e91
|
2064 2065 2066 2067 2068 2069 |
apparmor= [APPARMOR] Disable or enable AppArmor at boot time Format: { "0" | "1" } See security/apparmor/Kconfig help text 0 -- disable. 1 -- enable. Default value is set via kernel config option. |
cd4f0ef7c
|
2070 |
serialnumber [BUGS=X86-32] |
1da177e4c
|
2071 |
|
1da177e4c
|
2072 2073 |
shapers= [NET] Maximal number of shapers. |
a99130449
|
2074 |
|
b05f78f5c
|
2075 2076 2077 2078 2079 |
show_msr= [x86] show boot-time MSR settings Format: { <integer> } Show boot-time (BIOS-initialized) MSR settings. The parameter means the number of CPUs to show, for example 1 means boot CPU only. |
1da177e4c
|
2080 2081 |
simeth= [IA-64] simscsi= |
a99130449
|
2082 |
|
1da177e4c
|
2083 |
slram= [HW,MTD] |
f0630fff5
|
2084 2085 2086 2087 2088 2089 2090 |
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. |
c1aee215d
|
2091 2092 |
slub_max_order= [MM, SLUB] |
f0630fff5
|
2093 2094 2095 2096 |
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. |
c1aee215d
|
2097 2098 |
slub_min_objects= [MM, SLUB] |
f0630fff5
|
2099 2100 2101 2102 2103 2104 |
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. |
c1aee215d
|
2105 2106 2107 2108 |
For more information see Documentation/vm/slub.txt. slub_min_order= [MM, SLUB] Determines the mininum page order for slabs. Must be |
f0630fff5
|
2109 |
lower than slub_max_order. |
c1aee215d
|
2110 2111 2112 |
For more information see Documentation/vm/slub.txt. slub_nomerge [MM, SLUB] |
f0630fff5
|
2113 |
Disable merging of slabs with similar size. May be |
c1aee215d
|
2114 |
necessary if there is some reason to distinguish |
f0630fff5
|
2115 2116 |
allocs to different slabs. Debug options disable merging on their own. |
c1aee215d
|
2117 |
For more information see Documentation/vm/slub.txt. |
1da177e4c
|
2118 2119 |
smart2= [HW] Format: <io1>[,<io2>[,...,<io8>]] |
cd4f0ef7c
|
2120 |
smp-alt-once [X86-32,SMP] On a hotplug CPU system, only |
b7fb4af06
|
2121 |
attempt to substitute SMP alternatives once at boot. |
d0d4f69bb
|
2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 |
smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port smsc-ircc2.ircc_sir= [HW] SIR base I/O port smsc-ircc2.ircc_fir= [HW] FIR base I/O port smsc-ircc2.ircc_irq= [HW] IRQ line smsc-ircc2.ircc_dma= [HW] DMA channel smsc-ircc2.ircc_transceiver= [HW] Transceiver type: 0: Toshiba Satellite 1800 (GP data pin select) 1: Fast pin select (default) 2: ATC IRMode |
9c44bc03f
|
2132 2133 |
softlockup_panic= [KNL] Should the soft-lockup detector generate panics. |
44a4dcf75
|
2134 |
Format: <integer> |
9c44bc03f
|
2135 |
|
1da177e4c
|
2136 2137 2138 2139 |
sonypi.*= [HW] Sony Programmable I/O Control Device driver See Documentation/sonypi.txt specialix= [HW,SERIAL] Specialix multi-serial port adapter |
31c00fc15
|
2140 |
See Documentation/serial/specialix.txt. |
1da177e4c
|
2141 2142 2143 2144 2145 |
spia_io_base= [HW,MTD] spia_fio_base= spia_pedr= spia_peddr= |
f38f1d2aa
|
2146 2147 |
stacktrace [FTRACE] Enabled the stack tracer on boot up. |
1da177e4c
|
2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 |
sti= [PARISC,HW] Format: <num> Set the STI (builtin display/keyboard on the HP-PARISC machines) console (graphic card) which should be used as the initial boot-console. See also comment in drivers/video/console/sticore.c. sti_font= [HW] See comment in drivers/video/console/sticore.c. stifb= [HW] Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]] |
cbf110712
|
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 |
sunrpc.min_resvport= sunrpc.max_resvport= [NFS,SUNRPC] SunRPC servers often require that client requests originate from a privileged port (i.e. a port in the range 0 < portnr < 1024). An administrator who wishes to reserve some of these ports for other uses may adjust the range that the kernel's sunrpc client considers to be privileged using these two parameters to set the minimum and maximum port values. |
42a7fc4a6
|
2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 |
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) |
cbf110712
|
2186 2187 2188 2189 2190 2191 2192 2193 |
sunrpc.tcp_slot_table_entries= sunrpc.udp_slot_table_entries= [NFS,SUNRPC] Sets the upper limit on the number of simultaneous RPC calls that can be sent from the client to a server. Increasing these values may allow you to improve throughput, but will also increase the amount of memory reserved for use by the client. |
a42c390cf
|
2194 2195 2196 2197 |
swapaccount[=0|1] [KNL] Enable accounting of swap in memory resource controller if no parameter or 1 is given or disable it if 0 is given (See Documentation/cgroups/memory.txt) |
1da177e4c
|
2198 |
swiotlb= [IA-64] Number of I/O TLB slabs |
a99130449
|
2199 |
|
1da177e4c
|
2200 |
switches= [HW,M68k] |
e52eec13c
|
2201 2202 2203 2204 2205 2206 2207 2208 |
sysfs.deprecated=0|1 [KNL] Enable/disable old style sysfs layout for old udev on older distributions. When this option is enabled very new udev will not work anymore. When this option is disabled (or CONFIG_SYSFS_DEPRECATED not compiled) in older udev will not work anymore. Default depends on CONFIG_SYSFS_DEPRECATED_V2 set in the kernel configuration. |
5d6f647fc
|
2209 2210 2211 2212 2213 |
sysrq_always_enabled [KNL] Ignore sysrq setting - this boot parameter will neutralize any effect of /proc/sys/kernel/sysrq. Useful for debugging. |
1da177e4c
|
2214 |
tdfx= [HW,DRM] |
77437fd4e
|
2215 2216 2217 2218 2219 |
test_suspend= [SUSPEND] Specify "mem" (for Suspend-to-RAM) or "standby" (for standby suspend) as the system sleep state to briefly enter during system startup. The system is woken from this state using a wakeup-capable RTC alarm. |
1da177e4c
|
2220 2221 |
thash_entries= [KNL,NET] Set number of hash buckets for TCP connection |
f8707ec96
|
2222 2223 2224 |
thermal.act= [HW,ACPI] -1: disable all active trip points in all thermal zones <degrees C>: override all lowest active trip points |
c52a7419a
|
2225 2226 |
thermal.crt= [HW,ACPI] -1: disable all critical trip points in all thermal zones |
22a94d79a
|
2227 |
<degrees C>: override all critical trip points |
c52a7419a
|
2228 |
|
f54871456
|
2229 2230 2231 |
thermal.nocrt= [HW,ACPI] Set to disable actions on ACPI thermal zone critical and hot trip points. |
72b33ef8b
|
2232 2233 |
thermal.off= [HW,ACPI] 1: disable ACPI thermal control |
a70cdc520
|
2234 2235 |
thermal.psv= [HW,ACPI] -1: disable all passive trip points |
ada9cfdd1
|
2236 2237 |
<degrees C>: override all passive trip points to this value |
a70cdc520
|
2238 |
|
730ff34de
|
2239 2240 2241 2242 |
thermal.tzp= [HW,ACPI] Specify global default ACPI thermal zone polling rate <deci-seconds>: poll all this frequency 0: no polling (default) |
8d32a307e
|
2243 2244 2245 |
threadirqs [KNL] Force threading of all interrupt handlers except those marked explicitely IRQF_NO_THREAD. |
2b1a61f0a
|
2246 2247 2248 |
topology= [S390] Format: {off | on} Specify if the kernel should make use of the cpu |
f65e51d74
|
2249 2250 |
topology information if the hardware supports this. The scheduler will make use of this information and |
2b1a61f0a
|
2251 |
e.g. base its process migration decisions on it. |
c9af3fa9e
|
2252 |
Default is on. |
2b1a61f0a
|
2253 |
|
1da177e4c
|
2254 |
tp720= [HW,PS2] |
225a9be24
|
2255 2256 2257 2258 2259 2260 2261 2262 |
tpm_suspend_pcr=[HW,TPM] Format: integer pcr id Specify that at suspend time, the tpm driver should extend the specified pcr with zeros, as a workaround for some chips which fail to flush the last written pcr on TPM_SaveState. This will guarantee that all the other pcrs are saved. |
9d612beff
|
2263 2264 |
trace_buf_size=nn[KMG] [FTRACE] will set tracing buffer size. |
631595fbf
|
2265 |
|
020e5f85c
|
2266 2267 2268 2269 |
trace_event=[event-list] [FTRACE] Set and start specified trace events in order to facilitate early boot debugging. See also Documentation/trace/events.txt |
d3b8f889a
|
2270 |
tsc= Disable clocksource stability checks for TSC. |
395628ef4
|
2271 2272 |
Format: <string> [x86] reliable: mark tsc clocksource as reliable, this |
d3b8f889a
|
2273 2274 2275 2276 |
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. |
e82b8e4ea
|
2277 2278 2279 2280 |
[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 can add overhead. |
395628ef4
|
2281 |
|
a99130449
|
2282 2283 2284 2285 |
turbografx.map[2|3]= [HW,JOY] TurboGraFX parallel port interface Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7> |
1da177e4c
|
2286 |
See also Documentation/input/joystick-parport.txt |
b6935f8cd
|
2287 2288 2289 2290 |
udbg-immortal [PPC] When debugging early kernel crashes that happen after console_init() and before a proper console driver takes over, this boot options might help "seeing" what's going on. |
f86dcc5aa
|
2291 2292 |
uhash_entries= [KNL,NET] Set number of hash buckets for UDP/UDP-Lite connections |
5f8364b7d
|
2293 2294 2295 2296 2297 2298 2299 |
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. |
e3a61b0a8
|
2300 |
unknown_nmi_panic |
44a4dcf75
|
2301 |
[X86] Cause panic on unknown NMI. |
e3a61b0a8
|
2302 |
|
c4fc2342c
|
2303 2304 2305 2306 |
usbcore.authorized_default= [USB] Default USB device authorization: (default -1 = authorized except for wireless USB, 0 = not authorized, 1 = authorized) |
b5e795f8d
|
2307 2308 2309 2310 2311 |
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 |
eaafbc3a8
|
2312 |
to a negative value won't be autosuspended at all. |
b5e795f8d
|
2313 |
|
fd7c519dd
|
2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 |
usbcore.usbfs_snoop= [USB] Set to log all usbfs traffic (default 0 = off). usbcore.blinkenlights= [USB] Set to cycle leds on hubs (default 0 = off). usbcore.old_scheme_first= [USB] Start with the old device initialization scheme (default 0 = off). usbcore.use_both_schemes= [USB] Try the other device initialization scheme if the first one fails (default 1 = enabled). usbcore.initial_descriptor_timeout= [USB] Specifies timeout for the initial 64-byte USB_REQ_GET_DESCRIPTOR request in milliseconds (default 5000 = 5.0 seconds). |
1da177e4c
|
2332 2333 |
usbhid.mousepoll= [USBHID] The interval which mice are to be polled at. |
a99130449
|
2334 |
|
d4f373e57
|
2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 |
usb-storage.delay_use= [UMS] The delay in seconds before a new device is scanned for Logical Units (default 5). usb-storage.quirks= [UMS] A list of quirks entries to supplement or override the built-in unusual_devs list. List entries are separated by commas. Each entry has the form VID:PID:Flags where VID and PID are Vendor and Product ID values (4-digit hex numbers) and Flags is a set of characters, each corresponding to a common usb-storage quirk flag as follows: |
c838ea462
|
2347 2348 |
a = SANE_SENSE (collect more than 18 bytes of sense data); |
a0bb10811
|
2349 2350 |
b = BAD_SENSE (don't collect more than 18 bytes of sense data); |
d4f373e57
|
2351 2352 |
c = FIX_CAPACITY (decrease the reported device capacity by one sector); |
5116901d8
|
2353 2354 2355 2356 |
d = NO_READ_DISC_INFO (don't use READ_DISC_INFO command); e = NO_READ_CAPACITY_16 (don't use READ_CAPACITY_16 command); |
c838ea462
|
2357 2358 2359 |
h = CAPACITY_HEURISTICS (decrease the reported device capacity by one sector if the number is odd); |
d4f373e57
|
2360 2361 2362 2363 2364 2365 |
i = IGNORE_DEVICE (don't bind to this device); l = NOT_LOCKABLE (don't try to lock and unlock ejectable media); m = MAX_SECTORS_64 (don't transfer more than 64 sectors = 32 KB at a time); |
21c13a4f7
|
2366 2367 |
n = INITIAL_READ10 (force a retry of the initial READ(10) command); |
c838ea462
|
2368 2369 |
o = CAPACITY_OK (accept the capacity reported by the device); |
d4f373e57
|
2370 2371 2372 2373 2374 2375 2376 |
r = IGNORE_RESIDUE (the device reports bogus residue values); s = SINGLE_LUN (the device has only one Logical Unit); w = NO_WP_DETECT (don't test whether the medium is write-protected). Example: quirks=0419:aaf5:rl,0421:0433:rc |
ac1667db0
|
2377 2378 2379 2380 2381 2382 2383 2384 2385 |
user_debug= [KNL,ARM] Format: <int> See arch/arm/Kconfig.debug help text. 1 - undefined instruction events 2 - system calls 4 - invalid data aborts 8 - SIGSEGV faults 16 - SIGBUS faults Example: user_debug=31 |
143155920
|
2386 2387 2388 2389 2390 2391 |
userpte= [X86] Flags controlling user PTE allocations. nohigh = do not allocate PTE pages in HIGHMEM regardless of setting of CONFIG_HIGHPTE. |
6cececfce
|
2392 |
vdso= [X86,SH] |
1dbf527c5
|
2393 |
vdso=2: enable compat VDSO (default with COMPAT_VDSO) |
e6e5494cb
|
2394 2395 |
vdso=1: enable VDSO (default) vdso=0: disable VDSO mapping |
6cececfce
|
2396 |
vdso32= [X86] |
af65d6484
|
2397 2398 2399 |
vdso32=2: enable compat VDSO (default with COMPAT_VDSO) vdso32=1: enable 32-bit VDSO (default) vdso32=0: disable 32-bit VDSO mapping |
d080d397f
|
2400 2401 |
vector= [IA-64,SMP] vector=percpu: enable percpu vector domain |
1da177e4c
|
2402 2403 |
video= [FB] Frame buffer configuration See Documentation/fb/modedb.txt. |
cd4f0ef7c
|
2404 |
vga= [BOOT,X86-32] Select a particular video mode |
954a8b816
|
2405 |
See Documentation/x86/boot.txt and |
a99130449
|
2406 |
Documentation/svga.txt. |
1da177e4c
|
2407 2408 2409 |
Use vga=ask for menu. This is actually a boot loader parameter; the value is passed to the kernel using a special protocol. |
a99130449
|
2410 |
vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact |
1da177e4c
|
2411 2412 2413 2414 |
size of <nn>. This can be used to increase the minimum size (128MB on x86). It can also be used to decrease the size and leave more room for directly mapped kernel RAM. |
585c3047a
|
2415 2416 |
vmhalt= [KNL,S390] Perform z/VM CP command after system halt. Format: <command> |
1da177e4c
|
2417 |
|
585c3047a
|
2418 2419 2420 2421 2422 |
vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic. Format: <command> vmpoff= [KNL,S390] Perform z/VM CP command after power off. Format: <command> |
a99130449
|
2423 |
|
3ae36655b
|
2424 2425 2426 2427 2428 2429 2430 |
vsyscall= [X86-64] Controls the behavior of vsyscalls (i.e. calls to fixed addresses of 0xffffffffff600x00 from legacy code). Most statically-linked binaries and older versions of glibc use these calls. Because these functions are at fixed addresses, they make nice targets for exploits that can control RIP. |
2b666859e
|
2431 2432 |
emulate Vsyscalls turn into traps and are emulated reasonably safely. |
3ae36655b
|
2433 |
|
2b666859e
|
2434 2435 |
native [default] Vsyscalls are native syscall instructions. |
3ae36655b
|
2436 2437 2438 2439 2440 2441 2442 2443 |
This is a little bit faster than trapping and makes a few dynamic recompilers work better than they would in emulation mode. It also makes exploits much easier to write. none Vsyscalls don't work at all. This makes them quite hard to use for exploits but might break your system. |
9ea9a886b
|
2444 2445 2446 2447 |
vt.cur_default= [VT] Default cursor shape. Format: 0xCCBBAA, where AA, BB, and CC are the same as the parameters of the <Esc>[?A;B;Cc escape sequence; see VGA-softcursor.txt. Default: 2 = underline. |
0cb55ad2a
|
2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 |
vt.default_blu= [VT] Format: <blue0>,<blue1>,<blue2>,...,<blue15> Change the default blue palette of the console. This is a 16-member array composed of values ranging from 0-255. vt.default_grn= [VT] Format: <green0>,<green1>,<green2>,...,<green15> Change the default green palette of the console. This is a 16-member array composed of values ranging from 0-255. vt.default_red= [VT] Format: <red0>,<red1>,<red2>,...,<red15> Change the default red palette of the console. This is a 16-member array composed of values ranging from 0-255. vt.default_utf8= [VT] Format=<0|1> Set system-wide default UTF-8 mode for all tty's. Default is 1, i.e. UTF-8 mode is enabled for all newly opened terminals. |
f6c06b680
|
2472 2473 2474 2475 2476 2477 2478 2479 |
vt.global_cursor_default= [VT] Format=<-1|0|1> Set system-wide default for whether a cursor is shown on new VTs. Default is -1, i.e. cursors will be created by default unless overridden by individual drivers. 0 will hide cursors, 1 will display them. |
4724ba575
|
2480 2481 2482 2483 |
watchdog timers [HW,WDT] For information on watchdog timers, see Documentation/watchdog/watchdog-parameters.txt or other driver-specific files in the Documentation/watchdog/ directory. |
1da177e4c
|
2484 |
|
0cb55ad2a
|
2485 2486 2487 |
x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of default x2apic cluster mode on platforms supporting x2apic. |
bb24c4716
|
2488 2489 2490 2491 2492 |
x86_mrst_timer= [X86-32,APBT] Choose timer option for x86 Moorestown MID platform. Two valid options are apbt timer only and lapic timer plus one apbt timer for broadcast timer. x86_mrst_timer=apbt_only | lapic_and_apbt |
1da177e4c
|
2493 2494 |
xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks. xd_geo= See header of drivers/block/xd.c. |
c1c5413ad
|
2495 2496 2497 2498 2499 2500 2501 |
xen_emul_unplug= [HW,X86,XEN] Unplug Xen emulated devices Format: [unplug0,][unplug1] ide-disks -- unplug primary master IDE devices aux-ide-disks -- unplug non-primary-master IDE devices nics -- unplug network devices all -- unplug all emulated devices (NICs and IDE disks) |
1dc7ce99b
|
2502 2503 2504 |
unnecessary -- unplugging emulated devices is unnecessary even if the host did not respond to the unplug protocol |
c93a4dfb3
|
2505 |
never -- do not unplug even if version check succeeds |
c1c5413ad
|
2506 |
|
1da177e4c
|
2507 |
xirc2ps_cs= [NET,PCMCIA] |
a99130449
|
2508 2509 |
Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]] |
1da177e4c
|
2510 |
|
a99130449
|
2511 |
______________________________________________________________________ |
1da177e4c
|
2512 2513 |
TODO: |
1da177e4c
|
2514 |
Add more DRM drivers. |