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Documentation/kernel-parameters.txt 126 KB
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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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  	CLK	Common clock infrastructure is enabled.
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  	CMA	Contiguous Memory Area support 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.
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  	EVM	Extended Verification Module
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  	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.
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  	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.
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  	VMMIO   Driver for memory mapped virtio devices is enabled.
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  	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/runtime_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>...
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  	acpi_no_auto_serialize	[HW,ACPI]
  			Disable auto-serialization of AML methods
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  			AML control methods that contain the opcodes to create
  			named objects will be marked as "Serialized" by the
  			auto-serialization feature.
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  			This feature is enabled by default.
  			This option allows to turn off the feature.
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  	acpi_no_auto_ssdt	[HW,ACPI] Disable automatic loading of SSDT
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  	acpica_no_return_repair [HW, ACPI]
  			Disable AML predefined validation mechanism
  			This mechanism can repair the evaluation result to make
  			the return objects more ACPI specification compliant.
  			This option is useful for developers to identify the
  			root cause of an AML interpreter issue when the issue
  			has something to do with the repair mechanism.
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  	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
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  			acpi_osi="string1"	# add string1
  			acpi_osi="!string2"	# remove string2
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  			acpi_osi=!*		# remove all strings
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  			acpi_osi=!		# disable all built-in OS vendor
  						  strings
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  			acpi_osi=		# disable all strings
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  			'acpi_osi=!' can be used in combination with single or
  			multiple 'acpi_osi="string1"' to support specific OS
  			vendor string(s).  Note that such command can only
  			affect the default state of the OS vendor strings, thus
  			it cannot affect the default state of the feature group
  			strings and the current state of the OS vendor strings,
  			specifying it multiple times through kernel command line
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  			is meaningless.  This command is useful when one do not
  			care about the state of the feature group strings which
  			should be controlled by the OSPM.
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  			Examples:
  			  1. 'acpi_osi=! acpi_osi="Windows 2000"' is equivalent
  			     to 'acpi_osi="Windows 2000" acpi_osi=!', they all
  			     can make '_OSI("Windows 2000")' TRUE.
  
  			'acpi_osi=' cannot be used in combination with other
  			'acpi_osi=' command lines, the _OSI method will not
  			exist in the ACPI namespace.  NOTE that such command can
  			only affect the _OSI support state, thus specifying it
  			multiple times through kernel command line is also
  			meaningless.
  			Examples:
  			  1. 'acpi_osi=' can make 'CondRefOf(_OSI, Local1)'
  			     FALSE.
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  			'acpi_osi=!*' can be used in combination with single or
  			multiple 'acpi_osi="string1"' to support specific
  			string(s).  Note that such command can affect the
  			current state of both the OS vendor strings and the
  			feature group strings, thus specifying it multiple times
  			through kernel command line is meaningful.  But it may
  			still not able to affect the final state of a string if
  			there are quirks related to this string.  This command
  			is useful when one want to control the state of the
  			feature group strings to debug BIOS issues related to
  			the OSPM features.
  			Examples:
  			  1. 'acpi_osi="Module Device" acpi_osi=!*' can make
  			     '_OSI("Module Device")' FALSE.
  			  2. 'acpi_osi=!* acpi_osi="Module Device"' can make
  			     '_OSI("Module Device")' TRUE.
  			  3. 'acpi_osi=! acpi_osi=!* acpi_osi="Windows 2000"' is
  			     equivalent to
  			     'acpi_osi=!* acpi_osi=! acpi_osi="Windows 2000"'
  			     and
  			     'acpi_osi=!* acpi_osi="Windows 2000" acpi_osi=!',
  			     they all will make '_OSI("Windows 2000")' TRUE.
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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 }
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  	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).
72ad5d77f   Rafael J. Wysocki   ACPI / Sleep: All...
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  			nonvs prevents the kernel from saving/restoring the
  			ACPI NVS memory during suspend/hibernation and resume.
d7f0eea9e   Zhang Rui   ACPI: introduce k...
319
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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).
4af94f390   Randy Dunlap   doc: fix kernel-p...
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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.
00159a201   Prarit Bhargava   ACPI / memhotplug...
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  	acpi_no_memhotplug [ACPI] Disable memory hotplug.  Useful for kdump
  			   kernels.
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  	add_efi_memmap	[EFI; X86] Include EFI memory map in
  			kernel's map of available physical RAM.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
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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)
bcfde3347   Randy Dunlap   sound: move drive...
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  	ALSA		[HW,ALSA]
  			See Documentation/sound/alsa/alsa-parameters.txt
d944d549a   Russell King   ARM: allow alignm...
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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.
dfb09f9b7   Borislav Petkov   x86, amd: Avoid c...
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  	align_va_addr=	[X86-64]
  			Align virtual addresses by clearing slice [14:12] when
  			allocating a VMA at process creation time. This option
  			gives you up to 3% performance improvement on AMD F15h
  			machines (where it is enabled by default) for a
  			CPU-intensive style benchmark, and it can vary highly in
  			a microbenchmark depending on workload and compiler.
8360ee2f7   Borislav Petkov   x86, AMD: Correct...
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  			32: only for 32-bit processes
  			64: only for 64-bit processes
dfb09f9b7   Borislav Petkov   x86, amd: Avoid c...
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  			on: enable for both 32- and 64-bit processes
  			off: disable for both 32- and 64-bit processes
55034cd6e   Steven Rostedt (Red Hat)   tracing: Add allo...
367
368
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  	alloc_snapshot	[FTRACE]
  			Allocate the ftrace snapshot buffer on boot up when the
  			main buffer is allocated. This is handy if debugging
  			and you need to use tracing_snapshot() on boot up, and
  			do not want to use tracing_snapshot_alloc() as it needs
  			to be done where GFP_KERNEL allocations are allowed.
89e0b9a3f   Sedat Dilek   iommu/amd: Fix ty...
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  	amd_iommu=	[HW,X86-64]
54b4cbd26   Joerg Roedel   x86, AMD IOMMU: a...
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  			Pass parameters to the AMD IOMMU driver in the system.
  			Possible values are:
afa9fdc2f   FUJITA Tomonori   iommu: remove ful...
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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
a52357259   Joerg Roedel   x86/amd-iommu: Ad...
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  			off	  - do not initialize any AMD IOMMU found in
  				    the system
5abcdba4f   Joerg Roedel   iommu/amd: Put IO...
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  			force_isolation - Force device isolation for all
  					  devices. The IOMMU driver is not
  					  allowed anymore to lift isolation
  					  requirements as needed. This option
  					  does not override iommu=pt
afa9fdc2f   FUJITA Tomonori   iommu: remove ful...
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c099cf173   Shuah Khan   Documentation: ke...
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  	amd_iommu_dump=	[HW,X86-64]
  			Enable AMD IOMMU driver option to dump the ACPI table
  			for AMD IOMMU. With this option enabled, AMD IOMMU
  			driver will print ACPI tables for AMD IOMMU during
  			IOMMU initialization.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  	amijoy.map=	[HW,JOY] Amiga joystick support
  			Map of devices attached to JOY0DAT and JOY1DAT
  			Format: <a>,<b>
395cf9691   Paul Bolle   doc: fix broken r...
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  			See also Documentation/input/joystick.txt
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  	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>
a99130449   Randy Dunlap   [PATCH] kernel-pa...
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403
  	apc=		[HW,SPARC]
  			Power management functions (SPARCstation-4/5 + deriv.)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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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.
ca1eda2d7   Randy Dunlap   doc: small kernel...
408
  	apic=		[APIC,X86-32] Advanced Programmable Interrupt Controller
c8facbb62   Randy Dunlap   various doc/kerne...
409
  			Change the output verbosity whilst booting
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			Format: { quiet (default) | verbose | debug }
  			Change the amount of debugging information output
  			when initialising the APIC and IO-APIC components.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
413

b0f83b280   Brian Haley   doc: document IPv...
414
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  	autoconf=	[IPV6]
  			See Documentation/networking/ipv6.txt.
9636bc055   Cyrill Gorcunov   x86, apic: Explai...
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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
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  	apm=		[APM] Advanced Power Management
71f77055d   Pavel Machek   Doc*/kernel-param...
425
  			See header of arch/x86/kernel/apm_32.c.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
426

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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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
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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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
a99130449   Randy Dunlap   [PATCH] kernel-pa...
437
438
  	atkbd.set=	[HW] Select keyboard code set
  			Format: <int> (2 = AT (default), 3 = PS/2)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
439
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444
  
  	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))
a99130449   Randy Dunlap   [PATCH] kernel-pa...
445
446
447
  
  	atkbd.softrepeat= [HW]
  			Use software keyboard repeat
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
448

a106fb0c6   Richard Guy Briggs   documentation: do...
449
450
  	audit=		[KNL] Enable the audit sub-system
  			Format: { "0" | "1" } (0 = disabled, 1 = enabled)
d79611482   Eric Paris   audit: documentat...
451
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  			0 - kernel audit is disabled and can not be enabled
  			    until the next reboot
  			unset - kernel audit is initialized but disabled and
  			    will be fully enabled by the userspace auditd.
  			1 - kernel audit is initialized and partially enabled,
  			    storing at most audit_backlog_limit messages in
  			    RAM until it is fully enabled by the userspace
  			    auditd.
a106fb0c6   Richard Guy Briggs   documentation: do...
459
  			Default: unset
f3411cb2b   Richard Guy Briggs   audit: whitespace...
460

f910fde73   Richard Guy Briggs   audit: add kernel...
461
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  	audit_backlog_limit= [KNL] Set the audit queue size limit.
  			Format: <int> (must be >=0)
  			Default: 64
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  	baycom_epp=	[HW,AX25]
  			Format: <io>,<mode>
a99130449   Randy Dunlap   [PATCH] kernel-pa...
466

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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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.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
470
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  	baycom_ser_fdx=	[HW,AX25]
  			BayCom Serial Port AX.25 Modem (Full Duplex Mode)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			Format: <io>,<irq>,<mode>[,<baud>]
  			See header of drivers/net/hamradio/baycom_ser_fdx.c.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
474
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  	baycom_ser_hdx=	[HW,AX25]
  			BayCom Serial Port AX.25 Modem (Half Duplex Mode)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			Format: <io>,<irq>,<mode>
  			See header of drivers/net/hamradio/baycom_ser_hdx.c.
080506ad0   Paul Gortmaker   block: change con...
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  	blkdevparts=	Manual partition parsing of block device(s) for
  			embedded devices based on command line input.
  			See Documentation/block/cmdline-partition.txt
bfe8df3d3   Randy Dunlap   slow down printk ...
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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
35fc908dc   Andreas Herrmann   documentation: de...
485
  	bootmem_debug	[KNL] Enable bootmem allocator debug messages.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
486
  	bttv.card=	[HW,V4L] bttv (bt848 + bt878 based grabber cards)
a99130449   Randy Dunlap   [PATCH] kernel-pa...
487
488
  	bttv.radio=	Most important insmod options are available as
  			kernel args too.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
489
  	bttv.pll=	See Documentation/video4linux/bttv/Insmod-options
395cf9691   Paul Bolle   doc: fix broken r...
490
  	bttv.tuner=
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
491

4e89a2d8e   Will Schmidt   powerpc/pseries: ...
492
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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.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
495
  	c101=		[NET] Moxa C101 synchronous serial card
cd4f0ef7c   Alan Cox   doc/kernel-parame...
496
  	cachesize=	[BUGS=X86-32] Override level 2 CPU cache size detection.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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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.
14ff56bbb   Sebastian Ott   [S390] cio: Dump ...
502
503
  	ccw_timeout_log [S390]
  			See Documentation/s390/CommonIO for details.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
504

8bab8dded   Paul Menage   cgroups: add cgro...
505
506
  	cgroup_disable= [KNL] Disable a particular controller
  			Format: {name of the controller(s) to disable}
ca0bdbb5f   Qiang Huang   cgroup, doc: make...
507
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  			The effects of cgroup_disable=foo are:
  			- foo isn't auto-mounted if you mount all cgroups in
  			  a single hierarchy
  			- foo isn't visible as an individually mountable
  			  subsystem
  			{Currently only "memory" controller deal with this and
  			cut the overhead, others just disable the usage. So
  			only cgroup_disable=memory is actually worthy}
8bab8dded   Paul Menage   cgroups: add cgro...
515

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
516
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  	checkreqprot	[SELINUX] Set initial checkreqprot flag value.
  			Format: { "0" | "1" }
  			See security/selinux/Kconfig help text.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
519
520
  			0 -- check protection applied by kernel (includes
  				any implied execute protection).
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			1 -- check protection requested by application.
  			Default value is set via a kernel config option.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
523
524
  			Value can be changed at runtime via
  				/selinux/checkreqprot.
661ca0da3   Sebastian Ott   [S390] Cleanup in...
525
526
  	cio_ignore=	[S390]
  			See Documentation/s390/CommonIO for details.
1e435256d   Olof Johansson   clk: add clk_igno...
527
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  	clk_ignore_unused
  			[CLK]
  			Keep all clocks already enabled by bootloader on,
  			even if no driver has claimed them. This is useful
  			for debug and development, but should not be
  			needed on a platform with proper driver support.
  			For more information, see Documentation/clk.txt.
661ca0da3   Sebastian Ott   [S390] Cleanup in...
534

cd4f0ef7c   Alan Cox   doc/kernel-parame...
535
  	clock=		[BUGS=X86-32, HW] gettimeofday clocksource override.
734efb467   John Stultz   [PATCH] Time: Clo...
536
  			[Deprecated]
3f6dee9b2   Matt LaPlante   Fix some typos in...
537
  			Forces specified clocksource (if available) to be used
734efb467   John Stultz   [PATCH] Time: Clo...
538
  			when calculating gettimeofday(). If specified
3f6dee9b2   Matt LaPlante   Fix some typos in...
539
  			clocksource is not available, it defaults to PIT.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
540
  			Format: { pit | tsc | cyclone | pmtmr }
592913ecb   John Stultz   time: Kill off CO...
541
  	clocksource=	Override the default clocksource
3d6ac9843   Randy Dunlap   document clocksou...
542
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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
9863c90f6   Alok Kataria   x86, vmware: Remo...
552
  			[X86-32] pit,hpet,tsc;
3d6ac9843   Randy Dunlap   document clocksou...
553
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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
ac72e7888   Andi Kleen   x86: add generic ...
560
561
  	clearcpuid=BITNUM [X86]
  			Disable CPUID feature X for the kernel. See
07983f0e3   Randy Dunlap   documentation: up...
562
563
  			arch/x86/include/asm/cpufeature.h for the valid bit
  			numbers. Note the Linux specific bits are not necessarily
ac72e7888   Andi Kleen   x86: add generic ...
564
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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.
c64be2bb1   Marek Szyprowski   drivers: add Cont...
572
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  	cma=nn[MG]	[ARM,KNL]
  			Sets the size of kernel global memory area for contiguous
  			memory allocations. For more information, see
  			include/linux/dma-contiguous.h
14f966e79   Robert Jennings   powerpc/pseries: ...
576
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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
c79095092   Marek Szyprowski   ARM: integrate CM...
582
583
  	coherent_pool=nn[KMG]	[ARM,KNL]
  			Sets the size of memory pool for coherent, atomic dma
e9da6e990   Marek Szyprowski   ARM: dma-mapping:...
584
  			allocations, by default set to 256K.
c79095092   Marek Szyprowski   ARM: integrate CM...
585

6cececfce   Jaswinder Singh Rajput   x86, documentatio...
586
  	code_bytes	[X86] How many bytes of object code to print
a25bd9496   Arjan van de Ven   x86: add the "pri...
587
  			in an oops report.
86c418374   Chuck Ebbert   [PATCH] i386: add...
588
589
  			Range: 0 - 8192
  			Default: 64
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
590
  	com20020=	[HW,NET] ARCnet - COM20020 chipset
a99130449   Randy Dunlap   [PATCH] kernel-pa...
591
592
  			Format:
  			<io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
593
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595
  
  	com90io=	[HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
  			Format: <io>[,<irq>]
a99130449   Randy Dunlap   [PATCH] kernel-pa...
596
597
  	com90xx=	[HW,NET]
  			ARCnet - COM90xx chipset (memory-mapped buffers)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			Format: <io>[,<irq>[,<memstart>]]
  
  	condev=		[HW,S390] console device
  	conmode=
a99130449   Randy Dunlap   [PATCH] kernel-pa...
602

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
603
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  	console=	[KNL] Output console device and options.
  
  		tty<n>	Use the virtual console device <n>.
  
  		ttyS<n>[,options]
f1a1c2dc2   Randy Dunlap   [PATCH] doc: more...
608
  		ttyUSB0[,options]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
609
  			Use the specified serial port.  The options are of
f1a1c2dc2   Randy Dunlap   [PATCH] doc: more...
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  			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   Linus Torvalds   Linux-2.6.12-rc2
619

18a8bd949   Yinghai Lu   serial: convert e...
620
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  		uart[8250],io,<addr>[,options]
  		uart[8250],mmio,<addr>[,options]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			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.
a2fd64191   Konrad Rzeszutek Wilk   doc, kernel-param...
626
627
  		hvc<n>	Use the hypervisor console device <n>. This is for
  			both Xen and PowerPC hypervisors.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
628

f7511d5f6   Samuel Thibault   Basic braille scr...
629
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                  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   Daniel Mack   console: make bla...
633
634
635
  	consoleblank=	[KNL] The console blank (screen saver) timeout in
  			seconds. Defaults to 10*60 = 10mins. A value of 0
  			disables the blank timer.
4cb0e11b1   Hidehiro Kawai   coredump_filter: ...
636
637
638
639
  	coredump_filter=
  			[KNL] Change the default value for
  			/proc/<pid>/coredump_filter.
  			See also Documentation/filesystems/proc.txt.
62027aea2   Len Brown   cpuidle: create b...
640
641
  	cpuidle.off=1	[CPU_IDLE]
  			disable the cpuidle sub-system
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
642
  	cpcihp_generic=	[HW,PCI] Generic port I/O CompactPCI driver
a99130449   Randy Dunlap   [PATCH] kernel-pa...
643
644
  			Format:
  			<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
645

6f21e6463   Ahmed S. Darwish   Documentation: co...
646
647
648
649
650
651
652
  	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   Eric W. Biederman   [PATCH] kexec: ad...
653

fb391599f   Bernhard Walle   Add documentation...
654
655
656
657
658
  	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   Ahmed S. Darwish   Documentation: co...
659
  			Documentation/kdump/kdump.txt for an example.
fb391599f   Bernhard Walle   Add documentation...
660

adbc742bf   Yinghai Lu   x86, kdump: Chang...
661
  	crashkernel=size[KMG],high
55a20ee78   Yinghai Lu   x86, kdump: Retor...
662
663
664
665
666
667
  			[KNL, x86_64] range could be above 4G. Allow kernel
  			to allocate physical memory region from top, so could
  			be above 4G if system have more than 4G ram installed.
  			Otherwise memory region will be allocated below 4G, if
  			available.
  			It will be ignored if crashkernel=X is specified.
adbc742bf   Yinghai Lu   x86, kdump: Chang...
668
669
670
  	crashkernel=size[KMG],low
  			[KNL, x86_64] range under 4G. When crashkernel=X,high
  			is passed, kernel could allocate physical memory region
c729de8fc   Yinghai Lu   x86, kdump: Set c...
671
672
673
674
675
676
677
  			above 4G, that cause second kernel crash on system
  			that require some amount of low memory, e.g. swiotlb
  			requires at least 64M+32K low memory.  Kernel would
  			try to allocate 72M below 4G automatically.
  			This one let user to specify own low range under 4G
  			for second kernel instead.
  			0: to disable low allocation.
adbc742bf   Yinghai Lu   x86, kdump: Chang...
678
  			It will be ignored when crashkernel=X,high is not used
55a20ee78   Yinghai Lu   x86, kdump: Retor...
679
  			or memory reserved is below 4G.
c729de8fc   Yinghai Lu   x86, kdump: Set c...
680

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
681
682
683
684
685
  	cs89x0_dma=	[HW,NET]
  			Format: <dma>
  
  	cs89x0_media=	[HW,NET]
  			Format: { rj45 | aui | bnc }
a99130449   Randy Dunlap   [PATCH] kernel-pa...
686

a99130449   Randy Dunlap   [PATCH] kernel-pa...
687
  	dasd=		[HW,NET]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
688
689
690
691
692
693
  			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   Thomas Renninger   Dynamic Debug: In...
694
695
  	ddebug_query=   [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot
  			time. See Documentation/dynamic-debug-howto.txt for
29e36c9ff   Jim Cromie   dynamic_debug: up...
696
  			details.  Deprecated, see dyndbg.
a648ec05b   Thomas Renninger   Dynamic Debug: In...
697

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
698
  	debug		[KNL] Enable kernel debugging (events log level).
cae2ed9aa   Ingo Molnar   [PATCH] lockdep: ...
699
700
701
702
703
704
705
706
  	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   Thomas Gleixner   infrastructure to...
707
  	debug_objects	[KNL] Enable object debugging
3e8ebb5c4   Kyle McMartin   debug_objects: ad...
708
709
  	no_debug_objects
  			[KNL] Disable object debugging
c0a32fc5a   Stanislaw Gruszka   mm: more intensiv...
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
  	debug_guardpage_minorder=
  			[KNL] When CONFIG_DEBUG_PAGEALLOC is set, this
  			parameter allows control of the order of pages that will
  			be intentionally kept free (and hence protected) by the
  			buddy allocator. Bigger value increase the probability
  			of catching random memory corruption, but reduce the
  			amount of memory for normal system use. The maximum
  			possible value is MAX_ORDER/2.  Setting this parameter
  			to 1 or 2 should be enough to identify most random
  			memory corruption problems caused by bugs in kernel or
  			driver code when a CPU writes to (or reads from) a
  			random memory location. Note that there exists a class
  			of memory corruptions problems caused by buggy H/W or
  			F/W or by drivers badly programing DMA (basically when
  			memory is written at bus level and the CPU MMU is
  			bypassed) which are not detectable by
  			CONFIG_DEBUG_PAGEALLOC, hence this option will not help
  			tracking down these problems.
d3af01f18   Thomas Gleixner   Documentation: do...
728
  	debugpat	[X86] Enable PAT debugging
2d27a9661   Robert P. J. Day   Documentation: "...
729
  	decnet.addr=	[HW,NET]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
730
731
  			Format: <area>[,<node>]
  			See also Documentation/networking/decnet.txt.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
732
733
734
735
736
737
738
  	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   Antonino A. Daplas   vt: add documenta...
739

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
740
741
  	dhash_entries=	[KNL]
  			Set number of hash buckets for dentry cache.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
742

b0f83b280   Brian Haley   doc: document IPv...
743
744
  	disable=	[IPV6]
  			See Documentation/networking/ipv6.txt.
151e0c7de   HATAYAMA Daisuke   x86, apic, kexec:...
745
746
747
748
749
750
751
752
  	disable_cpu_apicid= [X86,APIC,SMP]
  			Format: <int>
  			The number of initial APIC ID for the
  			corresponding CPU to be disabled at boot,
  			mostly used for the kdump 2nd kernel to
  			disable BSP to wake up multiple CPUs without
  			causing system reset or hang due to sending
  			INIT from AP to BSP.
4e8b0cf46   Nishanth Aravamudan   powerpc/pseries: ...
753
754
755
  	disable_ddw     [PPC/PSERIES]
  			Disable Dynamic DMA Window support. Use this if
  			to workaround buggy firmware.
b0f83b280   Brian Haley   doc: document IPv...
756
757
  	disable_ipv6=	[IPV6]
  			See Documentation/networking/ipv6.txt.
95ffa2438   Yinghai Lu   x86: mtrr cleanup...
758
  	disable_mtrr_cleanup [X86]
95ffa2438   Yinghai Lu   x86: mtrr cleanup...
759
760
  			The kernel tries to adjust MTRR layout from continuous
  			to discrete, to make X server driver able to add WB
0cb55ad2a   Randy Dunlap   docs: alphabetize...
761
  			entry later. This parameter disables that.
95ffa2438   Yinghai Lu   x86: mtrr cleanup...
762

093af8d7f   Yinghai Lu   x86_32: trim memo...
763
  	disable_mtrr_trim [X86, Intel and AMD only]
99fc8d424   Jesse Barnes   x86, 32-bit: trim...
764
765
766
767
  			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   Jaswinder Singh Rajput   x86, documentatio...
768
  	disable_timer_pin_1 [X86]
0cb55ad2a   Randy Dunlap   docs: alphabetize...
769
770
  			Disable PIN 1 of APIC timer
  			Can be useful to work around chipset bugs.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
771
772
773
774
775
776
777
778
779
  	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   Joerg Roedel   dma-debug: add dm...
780
781
782
783
784
785
  	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.
da0df92b5   Carsten Emde   drm: allow loadin...
786
787
788
789
790
791
792
793
794
795
796
797
798
799
  	drm_kms_helper.edid_firmware=[<connector>:]<file>
  			Broken monitors, graphic adapters and KVMs may
  			send no or incorrect EDID data sets. This parameter
  			allows to specify an EDID data set in the
  			/lib/firmware directory that is used instead.
  			Generic built-in EDID data sets are used, if one of
  			edid/1024x768.bin, edid/1280x1024.bin,
  			edid/1680x1050.bin, or edid/1920x1080.bin is given
  			and no file with the same name exists. Details and
  			instructions how to build your own EDID data are
  			available in Documentation/EDID/HOWTO.txt. An EDID
  			data set will only be used for a particular connector,
  			if its name and a colon are prepended to the EDID
  			name.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
800
  	dscc4.setup=	[NET]
29e36c9ff   Jim Cromie   dynamic_debug: up...
801
802
803
804
  	dyndbg[="val"]		[KNL,DYNAMIC_DEBUG]
  	module.dyndbg[="val"]
  			Enable debug messages at boot time.  See
  			Documentation/dynamic-debug-howto.txt for details.
56aeeba8c   Mark Salter   doc/kernel-parame...
805
806
807
808
  	early_ioremap_debug [KNL]
  			Enable debug messages in early_ioremap support. This
  			is useful for tracking down temporary early mappings
  			which are not unmapped.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
809
810
811
  	earlycon=	[KNL] Output early console device and options.
  		uart[8250],io,<addr>[,options]
  		uart[8250],mmio,<addr>[,options]
1917ac76e   Samium Gromoff   serial: MMIO32 su...
812
  		uart[8250],mmio32,<addr>[,options]
0cb55ad2a   Randy Dunlap   docs: alphabetize...
813
814
  			Start an early, polled-mode console on the 8250/16550
  			UART at the specified I/O port or MMIO address.
162902466   Randy Dunlap   Documentation: ke...
815
816
  			MMIO inter-register address stride is either 8-bit
  			(mmio) or 32-bit (mmio32).
0cb55ad2a   Randy Dunlap   docs: alphabetize...
817
  			The options are the same as for ttyS, above.
147ea0911   Dave Hansen   x86, early-printk...
818
  	earlyprintk=	[X86,SH,BLACKFIN,ARM]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
819
  			earlyprintk=vga
72548e836   Matt Fleming   x86/efi: Add EFI ...
820
  			earlyprintk=efi
2482a92e7   Konrad Rzeszutek Wilk   doc, xen: Mention...
821
  			earlyprintk=xen
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
822
  			earlyprintk=serial[,ttySn[,baudrate]]
147ea0911   Dave Hansen   x86, early-printk...
823
  			earlyprintk=serial[,0x...[,baudrate]]
ea3acb199   Jason Wessel   x86: earlyprintk:...
824
  			earlyprintk=ttySn[,baudrate]
9780bc41d   Jason Wessel   USB: ehci-dbgp,do...
825
  			earlyprintk=dbgp[debugController#]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
826

147ea0911   Dave Hansen   x86, early-printk...
827
828
829
  			earlyprintk is useful when the kernel crashes before
  			the normal console is initialized. It is not enabled by
  			default because it has some cosmetic problems.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
830
  			Append ",keep" to not disable it when the real console
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
831
  			takes over.
72548e836   Matt Fleming   x86/efi: Add EFI ...
832
833
  			Only one of vga, efi, serial, or usb debug port can
  			be used at a time.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
834

147ea0911   Dave Hansen   x86, early-printk...
835
836
837
838
839
840
841
842
  			Currently only ttyS0 and ttyS1 may be specified by
  			name.  Other I/O ports may be explicitly specified
  			on some architectures (x86 and arm at least) by
  			replacing ttySn with an I/O port address, like this:
  				earlyprintk=serial,0x1008,115200
  			You can find the port for a given device in
  			/proc/tty/driver/serial:
  				2: uart:ST16650V2 port:00001008 irq:18 ...
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
843
844
845
  
  			Interaction with the standard serial driver is not
  			very good.
72548e836   Matt Fleming   x86/efi: Add EFI ...
846
847
  			The VGA and EFI output is eventually overwritten by
  			the real console.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
848

2482a92e7   Konrad Rzeszutek Wilk   doc, xen: Mention...
849
  			The xen output can only be used by Xen PV guests.
c700f013a   Chen, Gong   EDAC: Add an edac...
850
851
852
853
854
855
856
  	edac_report=	[HW,EDAC] Control how to report EDAC event
  			Format: {"on" | "off" | "force"}
  			on: enable EDAC to report H/W event. May be overridden
  			by other higher priority error reporting module.
  			off: disable H/W event reporting through EDAC.
  			force: enforce the use of EDAC to report H/W event.
  			default: on.
9731191f7   Jason Wessel   kgdboc: Add ekgdb...
857
858
  	ekgdboc=	[X86,KGDB] Allow early kernel console debugging
  			ekgdboc=kbd
25985edce   Lucas De Marchi   Fix common misspe...
859
  			This is designed to be used in conjunction with
9731191f7   Jason Wessel   kgdboc: Add ekgdb...
860
  			the boot argument: earlyprintk=vga
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
861
  	edd=		[EDD]
8c4dd6068   Tim Gardner   edd: add default ...
862
  			Format: {"off" | "on" | "skip[mbr]"}
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
863

d2f7cbe7b   Borislav Petkov   x86/efi: Runtime ...
864
865
866
867
868
  	efi=		[EFI]
  			Format: { "old_map" }
  			old_map [X86-64]: switch to the old ioremap-based EFI
  			runtime services mapping. 32-bit still uses this one by
  			default.
8c58bf3ee   Richard Weinberger   x86,efi: Implemen...
869
870
871
872
873
  	efi_no_storage_paranoia [EFI; X86]
  			Using this parameter you can use more than 50% of
  			your efi variable storage. Use this parameter only if
  			you are really sure that your UEFI does sane gc and
  			fulfills the spec otherwise your board may brick.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
874
875
  	eisa_irq_edge=	[PARISC,HW]
  			See header of drivers/parisc/eisa.c.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
876
  	elanfreq=	[X86-32]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
877
  			See comment before function elanfreq_setup() in
71f77055d   Pavel Machek   Doc*/kernel-param...
878
  			arch/x86/kernel/cpu/cpufreq/elanfreq.c.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
879
880
  
  	elevator=	[IOSCHED]
17a9e7bba   Randy Dunlap   Documentation: re...
881
  			Format: {"cfq" | "deadline" | "noop"}
395cf9691   Paul Bolle   doc: fix broken r...
882
  			See Documentation/block/cfq-iosched.txt and
a99130449   Randy Dunlap   [PATCH] kernel-pa...
883
  			Documentation/block/deadline-iosched.txt for details.
d3bf37955   Michael Holzheu   [S390] kdump: Add...
884
  	elfcorehdr=[size[KMG]@]offset[KMG] [IA64,PPC,SH,X86,S390]
a99130449   Randy Dunlap   [PATCH] kernel-pa...
885
  			Specifies physical address of start of kernel core
d3bf37955   Michael Holzheu   [S390] kdump: Add...
886
887
  			image elf header and optionally the size. Generally
  			kexec loader will pass this option to capture kernel.
aac04b32f   Vivek Goyal   [PATCH] kdump: x8...
888
  			See Documentation/kdump/kdump.txt for details.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
889

0cb55ad2a   Randy Dunlap   docs: alphabetize...
890
891
892
893
  	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   Randy Dunlap   doc: small kernel...
894
  	enable_timer_pin_1 [X86]
0cb55ad2a   Randy Dunlap   docs: alphabetize...
895
896
897
898
  			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   Linus Torvalds   Linux-2.6.12-rc2
899
900
901
902
903
904
905
  	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   Huang Ying   ACPI, APEI, Error...
906
907
908
  	erst_disable	[ACPI]
  			Disable Error Record Serialization Table (ERST)
  			support.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
909
910
911
  	ether=		[HW,NET] Ethernet cards parameters
  			This option is obsoleted by the "netdev=" option, which
  			has equivalent usage. See its documentation for details.
7102ebcd6   Mimi Zohar   evm: permit only ...
912
913
914
915
  	evm=		[EVM]
  			Format: { "fix" }
  			Permit 'security.evm' to be updated regardless of
  			current integrity status.
de1ba09b2   Akinobu Mita   [PATCH] fault inj...
916
917
918
919
920
  	failslab=
  	fail_page_alloc=
  	fail_make_request=[KNL]
  			General fault injection mechanism.
  			Format: <interval>,<probability>,<space>,<times>
395cf9691   Paul Bolle   doc: fix broken r...
921
  			See also Documentation/fault-injection/.
de1ba09b2   Akinobu Mita   [PATCH] fault inj...
922

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
923
  	floppy=		[HW]
31c00fc15   Randy Dunlap   Create/use more d...
924
  			See Documentation/blockdev/floppy.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
925

f13ae30e1   Alex Chiang   [IA64] allow user...
926
927
928
929
930
  	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.
69f2366c9   Chris Bainbridge   x86, cpu: Add for...
931
932
933
934
935
936
  	forcepae [X86-32]
  			Forcefully enable Physical Address Extension (PAE).
  			Many Pentium M systems disable PAE but may have a
  			functionally usable PAE implementation.
  			Warning: use of this parameter will taint the kernel
  			and may cause unknown problems.
d9e540762   Peter Zijlstra   ftrace: ftrace_du...
937
  	ftrace=[tracer]
2af15d6a4   Steven Rostedt   ftrace: add kerne...
938
  			[FTRACE] will set and start the specified tracer
d9e540762   Peter Zijlstra   ftrace: ftrace_du...
939
940
  			as early as possible in order to facilitate early
  			boot debugging.
cecbca96d   Frederic Weisbecker   tracing: Dump eit...
941
  	ftrace_dump_on_oops[=orig_cpu]
2af15d6a4   Steven Rostedt   ftrace: add kerne...
942
  			[FTRACE] will dump the trace buffers on oops.
cecbca96d   Frederic Weisbecker   tracing: Dump eit...
943
944
945
946
  			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   Steven Rostedt   ftrace: add kerne...
947
948
949
950
951
952
  
  	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   Randy Dunlap   Documentation: ke...
953
  			tracing directory.
2af15d6a4   Steven Rostedt   ftrace: add kerne...
954
955
956
957
958
959
  
  	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   Peter Zijlstra   ftrace: ftrace_du...
960

369bc18f9   Stefan Assmann   ftrace: add kerne...
961
962
963
964
965
966
  	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   Linus Torvalds   Linux-2.6.12-rc2
967
968
969
970
971
972
973
  	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   Yinghai Lu   x86: disable the ...
974
975
976
  	gart_fix_e820=  [X86_64] disable the fix e820 for K8 GART
  			Format: off | on
  			default: on
2521f2c22   Peter Oberparleiter   gcov: add gcov pr...
977
978
979
980
981
  	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   Linus Torvalds   Linux-2.6.12-rc2
982
  	gpt		[EFI] Forces disk with valid GPT signature but
6c5de79ba   Davidlohr Bueso   partitions/efi: c...
983
984
985
  			invalid Protective MBR to be treated as GPT. If the
  			primary GPT is corrupted, it enables the backup/alternate
  			GPT to be used instead.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
986

6cec9b07f   Andreas Larsson   can: grcan: Add d...
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
  	grcan.enable0=	[HW] Configuration of physical interface 0. Determines
  			the "Enable 0" bit of the configuration register.
  			Format: 0 | 1
  			Default: 0
  	grcan.enable1=	[HW] Configuration of physical interface 1. Determines
  			the "Enable 0" bit of the configuration register.
  			Format: 0 | 1
  			Default: 0
  	grcan.select=	[HW] Select which physical interface to use.
  			Format: 0 | 1
  			Default: 0
  	grcan.txsize=	[HW] Sets the size of the tx buffer.
  			Format: <unsigned int> such that (txsize & ~0x1fffc0) == 0.
  			Default: 1024
  	grcan.rxsize=	[HW] Sets the size of the rx buffer.
  			Format: <unsigned int> such that (rxsize & ~0x1fffc0) == 0.
  			Default: 1024
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1004
1005
  	hashdist=	[KNL,NUMA] Large hashes allocated during boot
  			are distributed across NUMA nodes.  Defaults on
162902466   Randy Dunlap   Documentation: ke...
1006
  			for 64-bit NUMA, off otherwise.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1007
  			Format: 0 | 1 (for off | on)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1008
1009
1010
1011
1012
  
  	hcl=		[IA-64] SGI's Hardware Graph compatibility layer
  
  	hd=		[EIDE] (E)IDE hard drive subsystem geometry
  			Format: <cyl>,<head>,<sect>
ea8c071ca   Huang Ying   ACPI, APEI, Docum...
1013
1014
1015
1016
  	hest_disable	[ACPI]
  			Disable Hardware Error Source Table (HEST) support;
  			corresponding firmware-first mode error processing
  			logic will be disabled.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1017
1018
1019
1020
  	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   Thomas Gleixner   [PATCH] hrtimers:...
1021
1022
1023
  	highres=	[KNL] Enable/disable high resolution timer mode.
  			Valid parameters: "on", "off"
  			Default: "on"
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1024
1025
  	hisax=		[HW,ISDN]
  			See Documentation/isdn/README.HiSax.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1026
1027
1028
1029
1030
1031
1032
1033
1034
  	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
3d035f580   Prarit Bhargava   drivers/char/hpet...
1035
1036
  	hpet_mmap=	[X86, HPET_MMAP] Allow userspace to mmap HPET
  			registers.  Default set by CONFIG_HPET_MMAP_DEFAULT.
b4718e628   Andi Kleen   x86: add hugepage...
1037
1038
  	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   Jon Tollefson   powerpc: support ...
1039
1040
1041
1042
1043
  			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   Andi Kleen   x86: add hugepage...
1044
1045
  			Note that 1GB pages can only be allocated at boot time
  			using hugepages= and not freed afterwards.
6902aa84f   Paul Mundt   doc: Add remainin...
1046

555d61d65   Hendrik Brueckner   [S390] update doc...
1047
1048
  	hvc_iucv=	[S390] Number of z/VM IUCV hypervisor console (HVC)
  			       terminal devices. Valid values: 0..8
431429ff7   Hendrik Brueckner   [S390] hvc_iucv: ...
1049
1050
1051
  	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   Hendrik Brueckner   [S390] provide do...
1052

fdabf525b   James Hogan   metag: Basic docu...
1053
1054
1055
  	hwthread_map=	[METAG] Comma-separated list of Linux cpu id to
  			        hardware thread id mappings.
  				Format: <cpu>:<hwthread>
7bf693951   Fabio M. Di Nitto   console: allow to...
1056
1057
1058
1059
1060
  	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   Jarkko Nikula   ARM: OMAP: Add co...
1061
  	i2c_bus=	[HW] Override the default board specific I2C bus speed
7954763bb   Jarkko Nikula   ARM: OMAP: Add me...
1062
1063
  			     or register an additional I2C bus that is not
  			     registered from board initialization code.
3a853fb93   Jarkko Nikula   ARM: OMAP: Add co...
1064
1065
  			     Format:
  			     <bus_id>,<clkrate>
36d957392   Jiri Kosina   Input: document i...
1066
  	i8042.debug	[HW] Toggle i8042 debug mode
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1067
  	i8042.direct	[HW] Put keyboard port into non-translated mode
84eb8d060   Matt LaPlante   Fix "can not" in ...
1068
1069
  	i8042.dumbkbd	[HW] Pretend that controller can only read data from
  			     keyboard and cannot control its state
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1070
1071
  			     (Don't attempt to blink the leds)
  	i8042.noaux	[HW] Don't check for auxiliary (== mouse) port
945ef0d42   Dmitry Torokhov   Input: i8042 - ad...
1072
  	i8042.nokbd	[HW] Don't check/create keyboard port
75d08c789   Jiri Kosina   Input: document i...
1073
1074
  	i8042.noloop	[HW] Disable the AUX Loopback command while probing
  			     for the AUX port
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1075
1076
1077
1078
  	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
24775d652   Masanari Iida   Documentation: Fi...
1079
  	i8042.notimeout	[HW] Ignore timeout condition signalled by controller
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1080
1081
1082
1083
  	i8042.reset	[HW] Reset the controller during init and cleanup
  	i8042.unlock	[HW] Unlock (ignore) the keylock
  
  	i810=		[HW,DRM]
e70c9d5e6   Dmitry Torokhov   [PATCH] I8K: use ...
1084
1085
1086
  	i8k.ignore_dmi	[HW] Continue probing hardware even if DMI data
  			indicates that the driver is running on unsupported
  			hardware.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1087
1088
1089
1090
1091
1092
1093
  	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.
4dca20efb   Carsten Emde   drm/i915: panel: ...
1094
  	i915.invert_brightness=
7bd90909b   Carsten Emde   drm/i915: panel: ...
1095
1096
  			[DRM] Invert the sense of the variable that is used to
  			set the brightness of the panel backlight. Normally a
4dca20efb   Carsten Emde   drm/i915: panel: ...
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
  			brightness value of 0 indicates backlight switched off,
  			and the maximum of the brightness value sets the backlight
  			to maximum brightness. If this parameter is set to 0
  			(default) and the machine requires it, or this parameter
  			is set to 1, a brightness value of 0 sets the backlight
  			to maximum brightness, and the maximum of the brightness
  			value switches the backlight off.
  			-1 -- never invert brightness
  			 0 -- machine default
  			 1 -- force brightness inversion
7bd90909b   Carsten Emde   drm/i915: panel: ...
1107

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1108
1109
  	icn=		[HW,ISDN]
  			Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
0af80c04e   David Fries   ide: ide.c 'clear...
1110
1111
  	ide-core.nodma=	[HW] (E)IDE subsystem
  			Format: =0.0 to prevent dma on hda, =0.1 hdb =1.0 hdc
075affcbe   Bartlomiej Zolnierkiewicz   ide: preserve Hos...
1112
1113
  			.vlb_clock .pci_clock .noflush .nohpa .noprobe .nowerr
  			.cdrom .chs .ignore_cable are additional options
1c10e9382   Randy Dunlap   ide: update refer...
1114
  			See Documentation/ide/ide.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1115

0cb55ad2a   Randy Dunlap   docs: alphabetize...
1116
1117
  	ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
  			Claim all unknown PCI IDE storage controllers.
f039b7547   Andi Kleen   [PATCH] x86: Don'...
1118
  	idle=		[X86]
69fb3676d   Len Brown   x86 idle: remove ...
1119
  			Format: idle=poll, idle=halt, idle=nomwait
ada9cfdd1   Randy Dunlap   doc: fix kernel-p...
1120
1121
1122
1123
  			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.
ada9cfdd1   Randy Dunlap   doc: fix kernel-p...
1124
  			idle=halt: Halt is forced to be used for CPU idle.
c1e3b377a   Zhao Yakui   ACPI: Create "idl...
1125
  			In such case C2/C3 won't be used again.
ada9cfdd1   Randy Dunlap   doc: fix kernel-p...
1126
  			idle=nomwait: Disable mwait for CPU C-states
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1127

792908225   Ingo Molnar   [PATCH] add ignor...
1128
1129
1130
  	ignore_loglevel	[KNL]
  			Ignore loglevel setting - this will print /all/
  			kernel messages to the console. Useful for debugging.
0eca6b7c7   Yanmin Zhang   printk: add modul...
1131
1132
1133
  			We also add it as printk module parameter, so users
  			could change it dynamically, usually by
  			/sys/module/printk/parameters/ignore_loglevel.
792908225   Ingo Molnar   [PATCH] add ignor...
1134

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1135
1136
  	ihash_entries=	[KNL]
  			Set number of hash buckets for inode cache.
2fe5d6def   Mimi Zohar   ima: integrity ap...
1137
1138
1139
  	ima_appraise=	[IMA] appraise integrity measurements
  			Format: { "off" | "enforce" | "fix" }
  			default: "enforce"
07f6a7941   Mimi Zohar   ima: add appraise...
1140
1141
1142
  	ima_appraise_tcb [IMA]
  			The builtin appraise policy appraises all files
  			owned by uid=0.
3323eec92   Mimi Zohar   integrity: IMA as...
1143
  	ima_hash=	[IMA]
e7a2ad7eb   Mimi Zohar   ima: enable suppo...
1144
1145
  			Format: { md5 | sha1 | rmd160 | sha256 | sha384
  				   | sha512 | ... }
3323eec92   Mimi Zohar   integrity: IMA as...
1146
  			default: "sha1"
e7a2ad7eb   Mimi Zohar   ima: enable suppo...
1147
1148
  			The list of supported hash algorithms is defined
  			in crypto/hash_info.h.
5789ba3bd   Eric Paris   IMA: Minimal IMA ...
1149
1150
1151
1152
1153
  	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.
9b9d4ce59   Roberto Sassu   ima: define kerne...
1154
1155
1156
1157
  	ima_template=   [IMA]
  			Select one of defined IMA measurements template formats.
  			Formats: { "ima" | "ima-ng" }
  			Default: "ima-ng"
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
  	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>
6bb2ff846   Fenghua Yu   x86 thermal: Disa...
1171
  	int_pln_enable  [x86] Enable power limit notification interrupt
d726d8d71   Mimi Zohar   integrity: move i...
1172
1173
1174
1175
  	integrity_audit=[IMA]
  			Format: { "0" | "1" }
  			0 -- basic integrity auditing messages. (Default)
  			1 -- additional integrity auditing messages.
ba3959276   Keshavamurthy, Anil S   Intel IOMMU: Inte...
1176
  	intel_iommu=	[DMAR] Intel IOMMU driver (DMAR) option
0cd5c3c80   Kyle McMartin   x86: disable inte...
1177
1178
  		on
  			Enable intel iommu driver.
ba3959276   Keshavamurthy, Anil S   Intel IOMMU: Inte...
1179
1180
1181
1182
1183
1184
1185
1186
  		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   Keshavamurthy, Anil S   Intel IOMMU: Inte...
1187
1188
  		forcedac [x86_64]
  			With this option iommu will not optimize to look
162902466   Randy Dunlap   Documentation: ke...
1189
  			for io virtual address below 32-bit forcing dual
7d3b03ce7   Keshavamurthy, Anil S   Intel IOMMU: Inte...
1190
  			address cycle on pci bus for cards supporting greater
162902466   Randy Dunlap   Documentation: ke...
1191
1192
  			than 32-bit addressing. The default is to look
  			for translation below 32-bit and if not available
7d3b03ce7   Keshavamurthy, Anil S   Intel IOMMU: Inte...
1193
  			then look in the higher range.
5e0d2a6fc   mark gross   PCI: iommu: iotlb...
1194
1195
1196
1197
  		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   Youquan Song   intel-iommu: Enab...
1198
1199
1200
1201
  		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.
2e92c7ad8   Masanari Iida   ACPI: kernel-para...
1202
1203
1204
1205
  
  	intel_idle.max_cstate=	[KNL,HW,ACPI,X86]
  			0	disables intel_idle and fall back on acpi_idle.
  			1 to 6	specify maximum depth of C-state.
6be264986   Dirk Brandewie   cpufreq / intel_p...
1206
1207
1208
1209
  	intel_pstate=  [X86]
  		       disable
  		         Do not enable intel_pstate as the default
  		         scaling driver for the supported processors
d1423d567   Chris Wright   intr-remap: allow...
1210
  	intremap=	[X86-64, Intel-IOMMU]
d1423d567   Chris Wright   intr-remap: allow...
1211
1212
1213
  			on	enable Interrupt Remapping (default)
  			off	disable Interrupt Remapping
  			nosid	disable Source ID checking
41750d31f   Suresh Siddha   x86, x2apic: Enab...
1214
1215
  			no_x2apic_optout
  				BIOS x2APIC opt-out request will be ignored
d1423d567   Chris Wright   intr-remap: allow...
1216

0cb55ad2a   Randy Dunlap   docs: alphabetize...
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
  	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
bcb71abe7   Alex Williamson   iommu: Add option...
1232
  		pt		[x86, IA-64]
bcb71abe7   Alex Williamson   iommu: Add option...
1233

0cb55ad2a   Randy Dunlap   docs: alphabetize...
1234
1235
1236
1237
  
  	io7=		[HW] IO7 for Marvel based alpha systems
  			See comment before marvel_specify_io7 in
  			arch/alpha/kernel/core_marvel.c.
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1238
  	io_delay=	[X86] I/O delay method
6e7c40259   Ingo Molnar   x86: various chan...
1239
1240
1241
1242
  		0x80
  			Standard port 0x80 based delay
  		0xed
  			Alternate port 0xed based delay (needed on some systems)
b02aae9cf   Rene Herman   x86: provide a DM...
1243
  		udelay
6e7c40259   Ingo Molnar   x86: various chan...
1244
1245
1246
  			Simple two microseconds delay
  		none
  			No delay
b02aae9cf   Rene Herman   x86: provide a DM...
1247

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1248
  	ip=		[IP_PNP]
dc7a08166   J. Bruce Fields   nfs: new subdir D...
1249
  			See Documentation/filesystems/nfs/nfsroot.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1250
1251
  
  	ip2=		[HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
c8facbb62   Randy Dunlap   various doc/kerne...
1252
1253
  			See comment before ip2_setup() in
  			drivers/char/ip2/ip2base.c.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1254

200803dfe   Alan Cox   [PATCH] irqpoll
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
  	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   Linus Torvalds   Linux-2.6.12-rc2
1265
  	isapnp=		[ISAPNP]
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1266
  			Format: <RDP>,<reset>,<pci_scan>,<verbosity>
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1267
1268
  
  	isolcpus=	[KNL,SMP] Isolate CPUs from the general scheduler.
22f2e2801   Derek Fults   [PATCH] get_optio...
1269
1270
1271
  			Format:
  			<cpu number>,...,<cpu number>
  			or
b225d44e2   Li Zefan   Documentation/ker...
1272
1273
  			<cpu number>-<cpu number>
  			(must be a positive range in ascending order)
22f2e2801   Derek Fults   [PATCH] get_optio...
1274
1275
  			or a mixture
  			<cpu number>,...,<cpu number>-<cpu number>
b225d44e2   Li Zefan   Documentation/ker...
1276

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1277
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  			This option can be used to specify one or more CPUs
  			to isolate from the general SMP balancing and scheduling
b225d44e2   Li Zefan   Documentation/ker...
1279
1280
  			algorithms. You can move a process onto or off an
  			"isolated" CPU via the CPU affinity syscalls or cpuset.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  			<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   Randy Dunlap   [PATCH] kernel-pa...
1285
1286
1287
  			alternative -- manually setting the CPU mask of all
  			tasks in the system -- can cause problems and
  			suboptimal load balancer performance.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1288

a99130449   Randy Dunlap   [PATCH] kernel-pa...
1289
  	iucv=		[HW,NET]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1290

7d8bfa26f   Joerg Roedel   iommu/amd: Docume...
1291
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  	ivrs_ioapic	[HW,X86_64]
  			Provide an override to the IOAPIC-ID<->DEVICE-ID
  			mapping provided in the IVRS ACPI table. For
  			example, to map IOAPIC-ID decimal 10 to
  			PCI device 00:14.0 write the parameter as:
  				ivrs_ioapic[10]=00:14.0
  
  	ivrs_hpet	[HW,X86_64]
  			Provide an override to the HPET-ID<->DEVICE-ID
  			mapping provided in the IVRS ACPI table. For
  			example, to map HPET-ID decimal 0 to
  			PCI device 00:14.0 write the parameter as:
  				ivrs_hpet[0]=00:14.0
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1304
1305
  	js=		[HW,JOY] Analog joystick
  			See Documentation/input/joystick.txt.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1306
  	keepinitrd	[HW,ARM]
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1307
  	kernelcore=nn[KMG]	[KNL,X86,IA-64,PPC] This parameter
ed7ed3651   Mel Gorman   handle kernelcore...
1308
1309
1310
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1314
  			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
675217fd9   Weiping Pan   Documentation/ker...
1315
  			of Movable pages.  The Movable zone is used for the
ed7ed3651   Mel Gorman   handle kernelcore...
1316
1317
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1321
  			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   Jason Wessel   echi-dbgp: Add ke...
1322
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1324
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1326
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  	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   Jason Wessel   kgdb,docs: Update...
1332
  	kgdboc=		[KGDB,HW] kgdb over consoles.
ada64e4c9   Jason Wessel   kgdboc,keyboard: ...
1333
1334
  			Requires a tty driver that supports console polling,
  			or a supported polling keyboard driver (non-usb).
65b5ac147   Jason Wessel   kgdb,docs: Update...
1335
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1337
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  			 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   Jason Wessel   kgdb: document pa...
1341

84c08fd61   Jason Wessel   kgdb,docs: Update...
1342
1343
  	kgdbwait	[KGDB] Stop kernel execution and enter the
  			kernel debugger at the earliest opportunity.
9bed90c6a   Florian Fainelli   Documentation: Do...
1344
1345
1346
  	kmac=		[MIPS] korina ethernet MAC address.
  			Configure the RouterBoard 532 series on-chip
  			Ethernet adapter MAC address.
04f70336c   Catalin Marinas   kmemleak: Add doc...
1347
1348
1349
  	kmemleak=	[KNL] Boot-time kmemleak enable/disable
  			Valid arguments: on, off
  			Default: on
c3ac14b26   Xishi Qiu   doc/kmemcheck: ad...
1350
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  	kmemcheck=	[X86] Boot-time kmemcheck enable/disable/one-shot mode
  			Valid arguments: 0, 1, 2
  			kmemcheck=0 (disabled)
  			kmemcheck=1 (enabled)
  			kmemcheck=2 (one-shot mode)
  			Default: 2 (one-shot mode)
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1356
  	kstack=N	[X86] Print N words from the kernel stack
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1357
  			in oops dumps.
fef07aae9   Andre Przywara   KVM: add module p...
1358
1359
  	kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs.
  			Default is 0 (don't ignore, but inject #GP)
a182d8737   Xiao Guangrong   KVM: document 'kv...
1360
1361
  	kvm.mmu_audit=	[KVM] This is a R/W parameter which allows audit
  			KVM MMU at runtime.
fef07aae9   Andre Przywara   KVM: add module p...
1362
  			Default is 0 (off)
fef07aae9   Andre Przywara   KVM: add module p...
1363
  	kvm-amd.nested=	[KVM,AMD] Allow nested virtualization in KVM/SVM.
8475f94ab   Xiao Guangrong   KVM: fix the desc...
1364
  			Default is 1 (enabled)
fef07aae9   Andre Przywara   KVM: add module p...
1365
1366
1367
  
  	kvm-amd.npt=	[KVM,AMD] Disable nested paging (virtualized MMU)
  			for all guests.
162902466   Randy Dunlap   Documentation: ke...
1368
  			Default is 1 (enabled) if in 64-bit or 32-bit PAE mode.
fef07aae9   Andre Przywara   KVM: add module p...
1369

fef07aae9   Andre Przywara   KVM: add module p...
1370
1371
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  	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)
e1a72ae28   Sasha Levin   KVM: nVMX: Docume...
1381
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  	kvm-intel.nested=
  			[KVM,Intel] Enable VMX nesting (nVMX).
  			Default is 0 (disabled)
fef07aae9   Andre Przywara   KVM: add module p...
1384
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  	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   Linus Torvalds   Linux-2.6.12-rc2
1392
  	l2cr=		[PPC]
a78bfbfcf   Robert Brose   [POWERPC] Add ker...
1393
  	l3cr=		[PPC]
cd4f0ef7c   Alan Cox   doc/kernel-parame...
1394
  	lapic		[X86-32,APIC] Enable the local APIC even if BIOS
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1395
  			disabled it.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1396

279f14614   Suresh Siddha   x86: apic: Use ts...
1397
1398
1399
  	lapic=		[x86,APIC] "notscdeadline" Do not use TSC deadline
  			value for LAPIC timer one-shot implementation. Default
  			back to the programmable timer unit in the LAPIC.
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1400
  	lapic_timer_c2_ok	[X86,APIC] trust the local apic timer
ada9cfdd1   Randy Dunlap   doc: fix kernel-p...
1401
  			in C2 power state.
e585bef81   Thomas Gleixner   [PATCH] i386: add...
1402

fcb71f6f0   FD Cami   Update kernel par...
1403
1404
1405
1406
  	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   Randy Dunlap   Documentation: ke...
1407
  			libata.dma=4	  Compact Flash DMA only
fcb71f6f0   FD Cami   Update kernel par...
1408
1409
  			Combinations also work, so libata.dma=3 enables DMA
  			for disks and CDROMs, but not CFs.
162902466   Randy Dunlap   Documentation: ke...
1410

203088715   Michael Prokop   Documentation/ker...
1411
1412
1413
  	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   FD Cami   Update kernel par...
1414

78e70c237   Dave Jones   libata: correct k...
1415
1416
1417
  	libata.noacpi	[LIBATA] Disables use of ACPI in libata suspend/resume
  			when set.
  			Format: <int>
332673257   Tejun Heo   libata: implement...
1418
1419
  	libata.force=	[LIBATA] Force configurations.  The format is comma
  			separated list of "[ID:]VAL" where ID is
4c44f309c   Roman Fietze   libata: fix docs,...
1420
  			PORT[.DEVICE].  PORT and DEVICE are decimal numbers
332673257   Tejun Heo   libata: implement...
1421
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  			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   Tejun Heo   libata: implement...
1449
1450
  			* nohrst, nosrst, norst: suppress hard, soft
                            and both resets.
ca6d43b05   Dan Williams   [SCSI] libata: re...
1451
1452
  			* rstonce: only attempt one reset during
  			  hot-unplug link recovery
43c9c5918   Tejun Heo   libata: implement...
1453
  			* dump_id: dump IDENTIFY data.
966fbe193   Vincent Pelletier   libata: Add atapi...
1454
  			* atapi_dmadir: Enable ATAPI DMADIR bridge support
b8bd6dc36   Robin H. Johnson   libata: disable a...
1455
  			* disable: Disable this device.
332673257   Tejun Heo   libata: implement...
1456
1457
  			If there are multiple matching configurations changing
  			the same attribute, the last one is used.
95f72d1ed   Yinghai Lu   lmb: rename to me...
1458
  	memblock=debug	[KNL] Enable memblock debug messages.
7c4be253d   Randy Dunlap   docs: add more ea...
1459

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1460
  	load_ramdisk=	[RAM] List of ramdisks to load from floppy
31c00fc15   Randy Dunlap   Create/use more d...
1461
  			See Documentation/blockdev/ramdisk.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1462

a6b25b675   Randy Dunlap   [PATCH] nlm kerne...
1463
1464
  	lockd.nlm_grace_period=P  [NFS] Assign grace period.
  			Format: <integer>
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1465

a6b25b675   Randy Dunlap   [PATCH] nlm kerne...
1466
1467
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1470
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  	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   Linus Torvalds   Linux-2.6.12-rc2
1474
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  	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   Randy Dunlap   Documentation: lo...
1491
1492
1493
  	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   Linus Torvalds   Linux-2.6.12-rc2
1494

accaa24c4   Randy Dunlap   fbcon: logo: disa...
1495
1496
1497
1498
  	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   Linus Torvalds   Linux-2.6.12-rc2
1499
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1501
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  	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   Randy Dunlap   Documentation: ke...
1532
  	machvec=	[IA-64] Force the use of a particular machine-vector
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1533
1534
  			(machvec) in a generic kernel.
  			Example: machvec=hpzx1_swiotlb
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1535

3209e70e5   Wu Zhangjin   MIPS: Loongson: A...
1536
1537
1538
  	machtype=	[Loongson] Share the same kernel image file between different
  			 yeeloong laptop.
  			Example: machtype=lemote-yeeloong-2f-7inch
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1539
1540
  	max_addr=nn[KMG]	[KNL,BOOT,ia64] All physical memory greater
  			than or equal to this physical address is ignored.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1541
1542
  
  	maxcpus=	[SMP] Maximum number of processors that	an SMP kernel
61ec7567d   Len Brown   ACPI: boot correc...
1543
1544
1545
1546
  			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   Linus Torvalds   Linux-2.6.12-rc2
1547

d134b00b9   Kay Sievers   loop: add BLK_DEV...
1548
1549
1550
1551
1552
1553
  	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   Bob Picco   [PATCH] Documenta...
1554

cd4f0ef7c   Alan Cox   doc/kernel-parame...
1555
  	mce		[X86-32] Machine Check Exception
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1556

71cced6eb   Uwe Hermann   doc/x86: fix doc ...
1557
  	mce=option	[X86-64] See Documentation/x86/x86_64/boot-options.txt
909dd324f   Andi Kleen   x86: clean up mce...
1558

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1559
1560
  	md=		[HW] RAID subsystems devices and level
  			See Documentation/md.txt.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1561

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1562
1563
1564
  	mdacon=		[MDA]
  			Format: <first>,<last>
  			Specifies range of consoles to be captured by the MDA.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1565

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1566
1567
1568
  	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.
fbb97d878   Wen Congyang   Documentation/ker...
1569
1570
1571
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  			[X86] Work as limiting max address. Use together
  			with memmap= to avoid physical address space collisions.
  			Without memmap= PCI devices could be placed at addresses
  			belonging to unused RAM.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1573

cd4f0ef7c   Alan Cox   doc/kernel-parame...
1574
  	mem=nopentium	[BUGS=X86-32] Disable usage of 4MB pages for kernel
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1575
  			memory.
6902aa84f   Paul Mundt   doc: Add remainin...
1576
1577
1578
  	memchunk=nn[KMG]
  			[KNL,SH] Allow user to override the default size for
  			per-device physically contiguous DMA buffers.
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1579
  	memmap=exactmap	[KNL,X86] Enable setting of an exact
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1580
1581
1582
1583
1584
1585
  			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]
277cba1d2   Randy Dunlap   Documentation/ker...
1586
1587
  			[KNL] Force usage of a specific region of memory.
  			Region of memory to be used is from ss to ss+nn.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1588
1589
1590
  
  	memmap=nn[KMG]#ss[KMG]
  			[KNL,ACPI] Mark specific memory as ACPI data.
277cba1d2   Randy Dunlap   Documentation/ker...
1591
  			Region of memory to be marked is from ss to ss+nn.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1592
1593
1594
  
  	memmap=nn[KMG]$ss[KMG]
  			[KNL,ACPI] Mark specific memory as reserved.
277cba1d2   Randy Dunlap   Documentation/ker...
1595
  			Region of memory to be reserved is from ss to ss+nn.
1312848e9   Pavel Machek   kernel-parameters...
1596
1597
1598
1599
  			Example: Exclude memory from 0x18690000-0x1869ffff
  			         memmap=64K$0x18690000
  			         or
  			         memmap=0x10000$0x18690000
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1600

9f077871c   Jeremy Fitzhardinge   x86: clean up mem...
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
  	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   Yinghai Lu   x86: enable memor...
1623
  	memtest=	[KNL,X86] Enable memtest
c64df7079   Yinghai Lu   x86: memtest boot...
1624
  			Format: <integer>
c64df7079   Yinghai Lu   x86: memtest boot...
1625
  			default : 0 <disable>
9e5f6cf5f   Andreas Herrmann   x86: update descr...
1626
1627
1628
1629
1630
1631
  			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   Yinghai Lu   x86: memtest boot...
1632

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1633
1634
  	meye.*=		[HW] Set MotionEye Camera parameters
  			See Documentation/video4linux/meye.txt.
8f36881b3   Andres Salomon   x86: Geode MFGPT ...
1635
1636
1637
  	mfgpt_irq=	[IA-32] Specify the IRQ to use for the
  			Multi-Function General Purpose Timers on AMD Geode
  			platforms.
e6c4dc6c3   Willy Tarreau   x86: GEODE add th...
1638
1639
1640
1641
  	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   Linus Torvalds   Linux-2.6.12-rc2
1642
  	mga=		[HW,DRM]
1c207f952   Randy Dunlap   Documentation/ker...
1643
1644
  	min_addr=nn[KMG]	[KNL,BOOT,ia64] All physical memory below this
  			physical address is ignored.
39f45d7bc   Michel Pollet   [ARM] MINI2440: D...
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
  	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   Mel Gorman   mm: add a basic d...
1665
1666
1667
1668
1669
1670
1671
  	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.
106a4ee25   Rusty Russell   module: signature...
1672
1673
1674
  	module.sig_enforce
  			[KNL] When CONFIG_MODULE_SIG is set, this means that
  			modules without (valid) signatures will fail to load.
2a039be7f   Paul Bolle   doc: put proper r...
1675
  			Note that if CONFIG_MODULE_SIG_FORCE is set, that
106a4ee25   Rusty Russell   module: signature...
1676
  			is always true, so this option does nothing.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
  	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   Jaswinder Singh Rajput   x86, documentatio...
1687
  	movablecore=nn[KMG]	[KNL,X86,IA-64,PPC] This parameter
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1688
1689
1690
1691
1692
1693
1694
1695
  			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.
c5320926e   Tang Chen   mem-hotplug: intr...
1696
1697
  	movable_node	[KNL,X86] Boot-time switch to enable the effects
  			of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1698
1699
  	MTD_Partition=	[MTD]
  			Format: <name>,<region-number>,<size>,<offset>
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1700
1701
  	MTD_Region=	[MTD] Format:
  			<name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1702
1703
  
  	mtdparts=	[MTD]
c8facbb62   Randy Dunlap   various doc/kerne...
1704
  			See drivers/mtd/cmdlinepart.c.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1705

4e89a2d8e   Will Schmidt   powerpc/pseries: ...
1706
1707
1708
  	multitce=off	[PPC]  This parameter disables the use of the pSeries
  			firmware feature for updating multiple TCE entries
  			at a time.
5988af231   Rohit Hagargundgi   mtd: Flex-OneNAND...
1709
1710
1711
1712
1713
1714
1715
1716
1717
  	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   Ben Dooks   [ARM] JIVE: Initi...
1718
1719
1720
1721
  	mtdset=		[ARM]
  			ARM/S3C2412 JIVE boot control
  
  			See arch/arm/mach-s3c2412/mach-jive.c
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1722
  	mtouchusb.raw_coordinates=
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1723
1724
  			[HW] Make the MicroTouch USB driver use raw coordinates
  			('y', default) or cooked coordinates ('n')
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1725

0cb55ad2a   Randy Dunlap   docs: alphabetize...
1726
  	mtrr_chunk_size=nn[KMG] [X86]
19f594600   Matt LaPlante   trivial: Miscella...
1727
  			used for mtrr cleanup. It is largest continuous chunk
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
  			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   Linus Torvalds   Linux-2.6.12-rc2
1742
  	n2=		[NET] SDL Inc. RISCom/N2 synchronous serial card
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1743
1744
1745
1746
  	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   Randy Dunlap   [PATCH] kernel-pa...
1747
1748
  			This usage is only documented in each driver source
  			file if at all.
584015727   Krzysztof Piotr Oledzki   netfilter: accoun...
1749
1750
1751
1752
  	nf_conntrack.acct=
  			[NETFILTER] Enable connection tracking flow accounting
  			0 to disable accounting
  			1 to enable accounting
d70a011db   Tim Gardner   netfilter: comple...
1753
  			Default value is 0.
584015727   Krzysztof Piotr Oledzki   netfilter: accoun...
1754

306a07536   Chuck Lever   NFS: Allow NFSROO...
1755
  	nfsaddrs=	[NFS] Deprecated.  Use ip= instead.
dc7a08166   J. Bruce Fields   nfs: new subdir D...
1756
  			See Documentation/filesystems/nfs/nfsroot.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1757
1758
  
  	nfsroot=	[NFS] nfs root filesystem for disk-less boxes.
dc7a08166   J. Bruce Fields   nfs: new subdir D...
1759
  			See Documentation/filesystems/nfs/nfsroot.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1760

306a07536   Chuck Lever   NFS: Allow NFSROO...
1761
1762
  	nfsrootdebug	[NFS] enable nfsroot debugging messages.
  			See Documentation/filesystems/nfs/nfsroot.txt.
a72b44222   Trond Myklebust   NFSv4: Allow user...
1763
1764
1765
  	nfs.callback_tcpport=
  			[NFS] set the TCP port on which the NFSv4 callback
  			channel should listen.
e571cbf1a   Trond Myklebust   NFS: Add a dns re...
1766
1767
1768
1769
1770
1771
1772
  	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   Trond Myklebust   NFSv4: Allow entr...
1773
1774
1775
  	nfs.idmap_cache_timeout=
  			[NFS] set the maximum lifetime for idmapper cache
  			entries.
f43bf0beb   Trond Myklebust   NFS: Add a boot p...
1776
1777
1778
1779
1780
1781
  	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.
ef159e917   Trond Myklebust   NFSv4.1: Add a mo...
1782
1783
1784
1785
1786
1787
1788
  	nfs.max_session_slots=
  			[NFSv4.1] Sets the maximum number of session slots
  			the client will attempt to negotiate with the server.
  			This limits the number of simultaneous RPC requests
  			that the client can send to the NFSv4.1 server.
  			Note that there is little point in setting this
  			value higher than the max_tcp_slot_table_limit.
b064eca2c   Trond Myklebust   NFSv4: Send unmap...
1789
  	nfs.nfs4_disable_idmapping=
074b1d12f   Trond Myklebust   NFSv4: Change the...
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
  			[NFSv4] When set to the default of '1', this option
  			ensures that both the RPC level authentication
  			scheme and the NFS level operations agree to use
  			numeric uids/gids if the mount is using the
  			'sec=sys' security flavour. In effect it is
  			disabling idmapping, which can make migration from
  			legacy NFSv2/v3 systems to NFSv4 easier.
  			Servers that do not support this mode of operation
  			will be autodetected by the client, and it will fall
  			back to using the idmapper.
  			To turn off this behaviour, set the value to '0'.
6f2ea7f2a   Chuck Lever   NFS: Add nfs4_uni...
1801
1802
1803
1804
1805
  	nfs.nfs4_unique_id=
  			[NFS4] Specify an additional fixed unique ident-
  			ification string that NFSv4 clients can insert into
  			their nfs_client_id4 string.  This is typically a
  			UUID that is generated at system install time.
b064eca2c   Trond Myklebust   NFSv4: Send unmap...
1806

db8ac8ba8   Weston Andros Adamson   NFSv4: Send imple...
1807
1808
1809
1810
1811
1812
1813
  	nfs.send_implementation_id =
  			[NFSv4.1] Send client implementation identification
  			information in exchange_id requests.
  			If zero, no implementation identification information
  			will be sent.
  			The default is to send the implementation identification
  			information.
f6de7a39c   Trond Myklebust   NFSv4: Document t...
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
  	
  	nfs.recover_lost_locks =
  			[NFSv4] Attempt to recover locks that were lost due
  			to a lease timeout on the server. Please note that
  			doing this risks data corruption, since there are
  			no guarantees that the file will remain unchanged
  			after the locks are lost.
  			If you want to enable the kernel legacy behaviour of
  			attempting to recover these locks, then set this
  			parameter to '1'.
  			The default parameter value of '0' causes the kernel
  			not to attempt recovery of lost locks.
db8ac8ba8   Weston Andros Adamson   NFSv4: Send imple...
1826

e9541ce8e   J. Bruce Fields   nfsd4: allow nume...
1827
1828
1829
1830
1831
1832
  	nfsd.nfs4_disable_idmapping=
  			[NFSv4] When set to the default of '1', the NFSv4
  			server will return only numeric uids and gids to
  			clients using auth_sys, and will accept numeric uids
  			and gids from such clients.  This is intended to ease
  			migration from NFSv2/v3.
db8ac8ba8   Weston Andros Adamson   NFSv4: Send imple...
1833

18d98f6c0   Sachin Bhamare   pnfs-obj: autolog...
1834
1835
1836
1837
1838
  	objlayoutdriver.osd_login_prog=
  			[NFS] [OBJLAYOUT] sets the pathname to the program which
  			is used to automatically discover and login into new
  			osd-targets. Please see:
  			Documentation/filesystems/pnfs.txt for more explanations
1e1030dcc   Paul Mundt   sh: nmi_debug sup...
1839
  	nmi_debug=	[KNL,AVR32,SH] Specify one or more actions to take
e7ba176b4   Haavard Skinnemoen   [AVR32] NMI debug...
1840
1841
  			when a NMI is triggered.
  			Format: [state][,regs][,debounce][,die]
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1842
  	nmi_watchdog=	[KNL,BUGS=X86] Debugging features for SMP kernels
fef2c9bc1   Don Zickus   kernel/watchdog.c...
1843
  			Format: [panic,][nopanic,][num]
5dc305587   Don Zickus   x86, NMI: Add bac...
1844
  			Valid num: 0
5b9a0e14e   Cyrill Gorcunov   x86: nmi - nmi_wa...
1845
  			0 - turn nmi_watchdog off
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1846
  			When panic is specified, panic when an NMI watchdog
fef2c9bc1   Don Zickus   kernel/watchdog.c...
1847
1848
  			timeout occurs (or 'nopanic' to override the opposite
  			default).
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1849
1850
  			This is useful when you use a panic=... timeout and
  			need the box quickly up again.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1851

bff38771e   Anton Vorontsov   netpoll: Introduc...
1852
1853
1854
1855
  	netpoll.carrier_timeout=
  			[NET] Specifies amount of time (in seconds) that
  			netpoll should wait for a carrier. By default netpoll
  			waits 4 seconds.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
1856
  	no387		[BUGS=X86-32] Tells the kernel to use the 387 maths
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1857
1858
  			emulation library even if a 387 maths coprocessor
  			is present.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1859
1860
1861
1862
1863
1864
1865
1866
1867
  	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.
134620f7a   Yanmin Zhang   printk: add conso...
1868
1869
1870
1871
1872
  			To facilitate more flexible debugging, we also add
  			console_suspend, a printk module parameter to control
  			it. Users could use console_suspend (usually
  			/sys/module/printk/parameters/console_suspend) to
  			turn on/off it dynamically.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1873

c1aee215d   Christoph Lameter   SLUB: More docume...
1874
1875
1876
  	noaliencache	[MM, NUMA, SLAB] Disables the allocation of alien
  			caches in the slab allocator.  Saves per-node memory,
  			but will impact performance.
3395ee058   Paul Menage   [PATCH] mm: add n...
1877

a99130449   Randy Dunlap   [PATCH] kernel-pa...
1878
  	noalign		[KNL,ARM]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1879
1880
  	noapic		[SMP,APIC] Tells the kernel to not make use of any
  			IOAPICs that may be present in the system.
8ab3820fd   Kees Cook   x86, kaslr: Retur...
1881
  	nokaslr		[X86]
e2b32e678   Kees Cook   x86, kaslr: rando...
1882
1883
  			Disable kernel and module base offset ASLR (Address
  			Space Layout Randomization) if built into the kernel.
8ab3820fd   Kees Cook   x86, kaslr: Retur...
1884

5091faa44   Mike Galbraith   sched: Add 'autog...
1885
  	noautogroup	Disable scheduler automatic task group creation.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1886
1887
1888
1889
  	nobats		[PPC] Do not use BATs for mapping kernel lowmem
  			on "Classic" PPC cores.
  
  	nocache		[ARM]
a99130449   Randy Dunlap   [PATCH] kernel-pa...
1890

0cb55ad2a   Randy Dunlap   docs: alphabetize...
1891
  	noclflush	[BUGS=X86] Don't use the CLFLUSH instruction
163ecdff0   Shailabh Nagar   [PATCH] delay acc...
1892
  	nodelayacct	[KNL] Disable per-task delay accounting
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1893
  	nodisconnect	[HW,SCSI,M68K] Disables SCSI disconnects.
6902aa84f   Paul Mundt   doc: Add remainin...
1894
  	nodsp		[SH] Disable hardware DSP at boot time.
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1895
  	noefi		[X86] Disable EFI runtime services support.
8b2cb7a8f   Huang, Ying   x86: 32-bit EFI r...
1896

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1897
  	noexec		[IA-64]
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1898
  	noexec		[X86]
f5a1b191b   Jiri Slaby   x86: fix exec map...
1899
  			On X86-32 available only on PAE configured kernels.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1900
  			noexec=on: enable non-executable mappings (default)
f5a1b191b   Jiri Slaby   x86: fix exec map...
1901
  			noexec=off: disable non-executable mappings
52b6179ac   H. Peter Anvin   x86, smap: Turn o...
1902
1903
1904
  	nosmap		[X86]
  			Disable SMAP (Supervisor Mode Access Prevention)
  			even if it is supported by processor.
de5397ad5   Fenghua Yu   x86, cpu: Enable/...
1905
  	nosmep		[X86]
52b6179ac   H. Peter Anvin   x86, smap: Turn o...
1906
  			Disable SMEP (Supervisor Mode Execution Prevention)
de5397ad5   Fenghua Yu   x86, cpu: Enable/...
1907
  			even if it is supported by processor.
f5a1b191b   Jiri Slaby   x86: fix exec map...
1908
1909
1910
1911
1912
1913
  	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   Linus Torvalds   Linux-2.6.12-rc2
1914

6902aa84f   Paul Mundt   doc: Add remainin...
1915
  	nofpu		[SH] Disable hardware FPU at boot time.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
1916
  	nofxsr		[BUGS=X86-32] Disables x86 floating point extended
4f8865112   Chuck Ebbert   [PATCH] i386: all...
1917
1918
  			register save and restore. The kernel will only save
  			legacy floating-point registers on task switch.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1919

0c752a933   Suresh Siddha   x86: introduce no...
1920
1921
1922
  	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.
5d2bd7009   Suresh Siddha   x86, fpu: decoupl...
1923
  	eagerfpu=	[X86]
e00229819   Suresh Siddha   x86, fpu: make ea...
1924
  			on	enable eager fpu restore
5d2bd7009   Suresh Siddha   x86, fpu: decoupl...
1925
  			off	disable eager fpu restore
e00229819   Suresh Siddha   x86, fpu: make ea...
1926
1927
  			auto	selects the default scheme, which automatically
  				enables eagerfpu restore for xsaveopt.
5d2bd7009   Suresh Siddha   x86, fpu: decoupl...
1928

01a24d2b9   Paulius Zaleckas   [ARM] 5437/1: Add...
1929
1930
1931
  	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   Randy Dunlap   [PATCH] kernel-pa...
1932

1f29fae29   Serge E. Hallyn   file capabilities...
1933
1934
1935
  	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   Linus Torvalds   Linux-2.6.12-rc2
1936
1937
1938
1939
1940
1941
  	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   Thomas Gleixner   [PATCH] tick-mana...
1942
1943
1944
  	nohz=		[KNL] Boottime enable/disable dynamic ticks
  			Valid arguments: on, off
  			Default: on
c5bfece2d   Frederic Weisbecker   nohz: Switch from...
1945
1946
  	nohz_full=	[KNL,BOOT]
  			In kernels built with CONFIG_NO_HZ_FULL=y, set
a831881be   Frederic Weisbecker   nohz: Basic full ...
1947
  			the specified list of CPUs whose tick will be stopped
0453b435d   Frederic Weisbecker   nohz: Force boot ...
1948
1949
  			whenever possible. The boot CPU will be forced outside
  			the range to maintain the timekeeping.
d1e43fa5f   Frederic Weisbecker   nohz: Ensure full...
1950
1951
  			The CPUs in this range must also be included in the
  			rcu_nocbs= set.
a831881be   Frederic Weisbecker   nohz: Basic full ...
1952

eeee7853c   Paul Mundt   sh: Add a command...
1953
  	noiotrap	[SH] Disables trapped I/O port accesses.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
1954
  	noirqdebug	[X86-32] Disables the code which attempts to detect and
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1955
  			disable unhandled interrupt sources.
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
1956
  	no_timer_check	[X86,APIC] Disables the code which tests for
8542b200c   Zachary Amsden   [PATCH] paravirt:...
1957
  			broken timer IRQ sources.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1958
1959
1960
1961
  	noisapnp	[ISAPNP] Disables ISA PnP code.
  
  	noinitrd	[RAM] Tells the kernel not to load any configured
  			initial RAM disk.
03ea81550   Weidong Han   x86, intr-remap: ...
1962
1963
  	nointremap	[X86-64, Intel-IOMMU] Do not enable interrupt
  			remapping.
d1423d567   Chris Wright   intr-remap: allow...
1964
  			[Deprecated - use intremap=off]
03ea81550   Weidong Han   x86, intr-remap: ...
1965

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1966
  	nointroute	[IA-64]
162902466   Randy Dunlap   Documentation: ke...
1967
  	nojitter	[IA-64] Disables jitter checking for ITC timers.
0aa366f35   Tony Luck   [IA64] Convert to...
1968

9cf4c4fcb   Jiri Kosina   KVM: x86: explain...
1969
  	no-kvmclock	[X86,KVM] Disable paravirtualized KVM clock driver
fd10cde92   Gleb Natapov   KVM paravirt: Add...
1970
1971
  	no-kvmapf	[X86,KVM] Disable paravirtualized asynchronous page
  			fault handling.
d910f5c10   Glauber Costa   KVM guest: KVM St...
1972
1973
1974
  	no-steal-acc    [X86,KVM] Disable paravirtualized steal time accounting.
  			steal time is computed, but won't influence scheduler
  			behaviour
cd4f0ef7c   Alan Cox   doc/kernel-parame...
1975
  	nolapic		[X86-32,APIC] Do not enable or use the local APIC.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1976

cd4f0ef7c   Alan Cox   doc/kernel-parame...
1977
  	nolapic_timer	[X86-32,APIC] Do not use the local APIC timer.
ad62ca2bd   Thomas Gleixner   [PATCH] i386: dis...
1978

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1979
1980
  	noltlbs		[PPC] Do not use large page/tlb entries for kernel
  			lowmem mapping on PPC40x.
312f1f014   Horms   [IA64] Document t...
1981
  	nomca		[IA-64] Disable machine check abort handling
cd4f0ef7c   Alan Cox   doc/kernel-parame...
1982
  	nomce		[X86-32] Machine Check Exception
abe37e5a1   Horms   Documentation: Re...
1983

83d7384f8   Andres Salomon   x86: Geode Multi-...
1984
1985
  	nomfgpt		[X86-32] Disable Multi-Function General Purpose
  			Timer usage (for AMD Geode machines).
bda626339   Don Zickus   x86, NMI: Add kno...
1986
1987
1988
  	nonmi_ipi	[X86] Disable using NMI IPIs during panic/reboot to
  			shutdown the other cpus.  Instead use the REBOOT_VECTOR
  			irq.
02608bef8   Dave Young   module: add kerne...
1989
  	nomodule	Disable module load
016ddd9b5   Jiri Kosina   x86: Put 'nopat' ...
1990
1991
  	nopat		[X86] Disable PAT (page attribute table extension of
  			pagetables) support.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
1992
1993
  	norandmaps	Don't use address space randomization.  Equivalent to
  			echo 0 > /proc/sys/kernel/randomize_va_space
bbff2168c   Jiri Kosina   paravirt: norepla...
1994
  	noreplace-paravirt	[X86,IA-64,PV_OPS] Don't patch paravirt_ops
959b4fdfe   Jeremy Fitzhardinge   [PATCH] i386: PAR...
1995

cd4f0ef7c   Alan Cox   doc/kernel-parame...
1996
  	noreplace-smp	[X86-32,SMP] Don't replace SMP instructions
b7fb4af06   Jeremy Fitzhardinge   [PATCH] i386: All...
1997
  			with UP alternatives
49d859d78   H. Peter Anvin   x86, random: Veri...
1998
1999
2000
2001
  	nordrand	[X86] Disable the direct use of the RDRAND
  			instruction even if it is supported by the
  			processor.  RDRAND is still available to user
  			space applications.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2002
2003
  	noresume	[SWSUSP] Disables resume and restores original swap
  			space.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2004
2005
2006
2007
2008
  	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   Alan Cox   doc/kernel-parame...
2009
  	nosep		[BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support.
4f8865112   Chuck Ebbert   [PATCH] i386: all...
2010

61ec7567d   Len Brown   ACPI: boot correc...
2011
2012
  	nosmp		[SMP] Tells an SMP kernel to act as a UP kernel,
  			and disable the IO APIC.  legacy for "maxcpus=0".
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2013

97842216b   Dave Jones   Allow softlockup ...
2014
  	nosoftlockup	[KNL] Disable the soft-lockup detector.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2015
  	nosync		[HW,M68K] Disables sync negotiation for all devices.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
2016
  	notsc		[BUGS=X86-32] Disable Time Stamp Counter
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2017
2018
  
  	nousb		[USB] Disable the USB subsystem
551423748   Ben Hutchings   watchdog: Improve...
2019
  	nowatchdog	[KNL] Disable the lockup detector (NMI watchdog).
58687acba   Don Zickus   lockup_detector: ...
2020

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2021
  	nowb		[ARM]
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2022

2b2fd87a6   Weidong Han   docs, x86: add no...
2023
  	nox2apic	[X86-64,APIC] Do not enable x2APIC mode.
f78cff48c   Fenghua Yu   doc: Add x86 CPU0...
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
  	cpu0_hotplug	[X86] Turn on CPU0 hotplug feature when
  			CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off.
  			Some features depend on CPU0. Known dependencies are:
  			1. Resume from suspend/hibernate depends on CPU0.
  			Suspend/hibernate will fail if CPU0 is offline and you
  			need to online CPU0 before suspend/hibernate.
  			2. PIC interrupts also depend on CPU0. CPU0 can't be
  			removed if a PIC interrupt is detected.
  			It's said poweroff/reboot may depend on CPU0 on some
  			machines although I haven't seen such issues so far
  			after CPU0 is offline on a few tested machines.
  			If the dependencies are under your control, you can
  			turn on cpu0_hotplug.
162902466   Randy Dunlap   Documentation: ke...
2037
  	nptcg=		[IA-64] Override max number of concurrent global TLB
a6c75b86c   Fenghua Yu   [IA64] Kernel par...
2038
2039
  			purges which is reported from either PAL_VM_SUMMARY or
  			SAL PALO.
2b633e3fa   Yinghai Lu   smp: Use nr_cpus=...
2040
2041
2042
2043
2044
  	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   Randy Dunlap   docs: alphabetize...
2045
  	nr_uarts=	[SERIAL] maximum number of UARTs to be registered.
1a687c2e9   Mel Gorman   mm: sched: numa: ...
2046
2047
  	numa_balancing=	[KNL,X86] Enable or disable automatic NUMA balancing.
  			Allowed values are enable and disable
f0c0b2b80   KAMEZAWA Hiroyuki   change zonelist o...
2048
2049
2050
2051
  	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   Randy Dunlap   docs: add more ea...
2052
2053
2054
  	ohci1394_dma=early	[HW] enable debugging via the ohci1394 driver.
  			See Documentation/debugging-via-ohci1394.txt for more
  			info.
3ef0e1f8c   Andres Salomon   x86: olpc: add On...
2055
2056
2057
2058
2059
2060
  	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   Tony Lindgren   omap: mux: Add ne...
2061
2062
2063
2064
  	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   Linus Torvalds   Linux-2.6.12-rc2
2065
2066
  	oprofile.timer=	[HW]
  			Use timer interrupt instead of performance counters
7e4e0bd50   Robert Richter   oprofile: introdu...
2067
2068
2069
  	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   Robert Richter   x86/oprofile: ren...
2070
2071
  			Format: { arch_perfmon }
  			arch_perfmon: [X86] Force use of architectural
7e4e0bd50   Robert Richter   oprofile: introdu...
2072
2073
  				perfmon on Intel CPUs instead of the
  				CPU specific event set.
159a80b21   Robert Richter   oprofile, x86: Ad...
2074
2075
2076
  			timer: [X86] Force use of architectural NMI
  				timer mode (see also oprofile.timer
  				for generic hr timer mode)
dd3c4670d   Andreas Krebbel   oprofile, s390: A...
2077
2078
  				[s390] Force legacy basic mode sampling
                                  (report cpu_type "timer")
1dcdb5a9e   Andi Kleen   oprofile: re-add ...
2079

44a4dcf75   Randy Dunlap   Documentation: up...
2080
2081
2082
  	oops=panic	Always panic on oopses. Default is to just kill the
  			process, but there is a small probability of
  			deadlocking the machine.
d404ab0a1   Olaf Hering   move x86 specific...
2083
2084
  			This will also cause panics on machine check exceptions.
  			Useful together with panic=30 to trigger a reboot.
bcfde3347   Randy Dunlap   sound: move drive...
2085
2086
  	OSS		[HW,OSS]
  			See Documentation/sound/oss/oss-parameters.txt
44a4dcf75   Randy Dunlap   Documentation: up...
2087
  	panic=		[KNL] Kernel behaviour on panic: delay <timeout>
4302fbc8e   Hugh Dickins   panic: panic=-1 f...
2088
2089
2090
  			timeout > 0: seconds before rebooting
  			timeout = 0: wait forever
  			timeout < 0: reboot immediately
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2091
2092
2093
2094
2095
2096
2097
  			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   Randy Dunlap   [PATCH] kernel-pa...
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
  			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   Linus Torvalds   Linux-2.6.12-rc2
2120
  			Format: [spp|ps2|epp|ecp|ecpepp]
dd287796d   Andrew Morton   [PATCH] pause_on_...
2121
2122
2123
2124
  	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   Linus Torvalds   Linux-2.6.12-rc2
2125
2126
2127
2128
  	pcbit=		[HW,ISDN]
  
  	pcd.		[PARIDE]
  			See header of drivers/block/paride/pcd.c.
31c00fc15   Randy Dunlap   Create/use more d...
2129
  			See also Documentation/blockdev/paride.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2130

a99130449   Randy Dunlap   [PATCH] kernel-pa...
2131
  	pci=option[,option...]	[PCI] various PCI subsystem options:
1cc0ca26c   Bjorn Helgaas   PCI/x86: document...
2132
2133
  		earlydump	[X86] dump PCI config space before the kernel
  			        changes anything
c01156061   Andi Kleen   PCI: Document tha...
2134
  		off		[X86] don't probe for the PCI bus
cd4f0ef7c   Alan Cox   doc/kernel-parame...
2135
  		bios		[X86-32] force use of PCI BIOS, don't access
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2136
2137
  				the hardware directly. Use this if your machine
  				has a non-standard PCI host bridge.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
2138
  		nobios		[X86-32] disallow use of PCI BIOS, only direct
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2139
2140
2141
  				hardware access methods are allowed. Use this
  				if you experience crashes upon bootup and you
  				suspect they are caused by the BIOS.
c01156061   Andi Kleen   PCI: Document tha...
2142
  		conf1		[X86] Force use of PCI Configuration
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2143
  				Mechanism 1.
c01156061   Andi Kleen   PCI: Document tha...
2144
  		conf2		[X86] Force use of PCI Configuration
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2145
  				Mechanism 2.
7f7857636   Randy Dunlap   pci: implement "p...
2146
2147
2148
  		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   Jeff Garzik   PCI: Add 'nodomai...
2149
2150
  		nodomains	[PCI] Disable support for multiple PCI
  				root domains (aka PCI segments, in ACPI-speak).
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
2151
  		nommconf	[X86] Disable use of MMCONFIG for PCI
61be6d660   Bjorn Helgaas   [PATCH] mmconfig:...
2152
  				Configuration
129830773   Andreas Herrmann   x86/PCI: add desc...
2153
2154
2155
  		check_enable_amd_mmconf [X86] check for and enable
  				properly configured MMIO access to PCI
  				config space on AMD family 10h CPU
309e57df7   Matthew Wilcox   [PATCH] PCI: Prov...
2156
2157
2158
  		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   Stefan Assmann   x86, pci: introdu...
2159
2160
2161
  		noioapicquirk	[APIC] Disable all boot interrupt quirks.
  				Safety option to keep boot IRQs enabled. This
  				should never be necessary.
9197979b5   Stefan Assmann   x86, pci: introdu...
2162
2163
2164
2165
  		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   Stefan Assmann   x86, pci: introdu...
2166
2167
2168
2169
  		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   Alan Cox   doc/kernel-parame...
2170
  		biosirq		[X86-32] Use PCI BIOS calls to get the interrupt
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2171
2172
2173
2174
2175
2176
2177
  				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   Andi Kleen   PCI: Document tha...
2178
  		rom		[X86] Assign address space to expansion ROMs.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2179
2180
2181
  				Use with caution as certain devices share
  				address decoders between ROMs and other
  				resources.
c01156061   Andi Kleen   PCI: Document tha...
2182
  		norom		[X86] Do not assign address space to
bb71ad880   Gary Hade   PCI: boot paramet...
2183
2184
  				expansion ROMs that do not already have
  				BIOS assigned address ranges.
7bd1c365f   Mike Habeck   x86/PCI: Add opti...
2185
2186
  		nobar		[X86] Do not assign address space to the
  				BARs that weren't assigned by the BIOS.
c01156061   Andi Kleen   PCI: Document tha...
2187
  		irqmask=0xMMMM	[X86] Set a bit mask of IRQs allowed to be
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2188
2189
2190
  				assigned automatically to PCI devices. You can
  				make the kernel exclude IRQs of your ISA cards
  				this way.
c01156061   Andi Kleen   PCI: Document tha...
2191
  		pirqaddr=0xAAAAA	[X86] Specify the physical address
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2192
2193
2194
  				of the PIRQ table (normally generated
  				by the BIOS) if it is outside the
  				F0000h-100000h range.
c01156061   Andi Kleen   PCI: Document tha...
2195
  		lastbus=N	[X86] Scan all buses thru bus #N. Can be
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2196
2197
2198
  				useful if the kernel is unable to find your
  				secondary buses and you want to tell it
  				explicitly which ones they are.
c01156061   Andi Kleen   PCI: Document tha...
2199
  		assign-busses	[X86] Always assign all PCI bus
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2200
2201
  				numbers ourselves, overriding
  				whatever the firmware may have done.
c01156061   Andi Kleen   PCI: Document tha...
2202
  		usepirqmask	[X86] Honor the possible IRQ mask stored
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2203
2204
2205
2206
2207
  				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   Andi Kleen   PCI: Document tha...
2208
  		noacpi		[X86] Do not use ACPI for IRQ routing
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2209
  				or for PCI scanning.
7bc5e3f2b   Bjorn Helgaas   x86/PCI: use host...
2210
2211
2212
2213
2214
2215
  		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   Randy Dunlap   [PATCH] kernel-pa...
2216
2217
2218
2219
  		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   Yinghai Lu   x86/pci: add pci=...
2220
2221
  		skip_isa_align	[X86] do not align io start addr, so can
  				handle more pci cards
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2222
2223
2224
2225
2226
  		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   Andi Kleen   [PATCH] x86: Allo...
2227
2228
2229
2230
2231
  		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   Matt Domsch   PCI: optionally s...
2232
2233
2234
2235
  		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.
fa2387124   Yijing Wang   PCI: Document MPS...
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
  		pcie_bus_tune_off	Disable PCIe MPS (Max Payload Size)
  				tuning and use the BIOS-configured MPS defaults.
  		pcie_bus_safe	Set every device's MPS to the largest value
  				supported by all devices below the root complex.
  		pcie_bus_perf	Set device MPS to the largest allowable MPS
  				based on its parent bus. Also set MRRS (Max
  				Read Request Size) to the largest supported
  				value (no larger than the MPS that the device
  				or bus can support) for best performance.
  		pcie_bus_peer2peer	Set every device's MPS to 128B, which
  				every device is guaranteed to support. This
  				configuration allows peer-to-peer DMA between
  				any pair of devices, possibly at the cost of
  				reduced performance.  This also guarantees
  				that hot-added devices will work.
4516a618a   Atsushi Nemoto   PCI: Make CARDBUS...
2251
2252
2253
2254
2255
2256
  		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   Yuji Shimada   PCI: allow assign...
2257
2258
2259
2260
2261
2262
2263
2264
2265
  		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   Andrew Patterson   PCI: Add support ...
2266
2267
2268
2269
2270
2271
  		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.
8c8803c59   Yijing Wang   PCI: Document hpi...
2272
2273
2274
2275
2276
2277
  		hpiosize=nn[KMG]	The fixed amount of bus space which is
  				reserved for hotplug bridge's IO window.
  				Default size is 256 bytes.
  		hpmemsize=nn[KMG]	The fixed amount of bus space which is
  				reserved for hotplug bridge's memory window.
  				Default size is 2 megabytes.
b55438fdd   Yinghai Lu   PCI: prepare pci=...
2278
2279
2280
2281
2282
2283
2284
  		realloc=	Enable/disable reallocating PCI bridge resources
  				if allocations done by BIOS are too small to
  				accommodate resources required by all child
  				devices.
  				off: Turn realloc off
  				on: Turn realloc on
  		realloc		same as realloc=on
6748dcc26   Rafael J. Wysocki   PCI / PCIe: Intro...
2285
  		noari		do not use PCIe ARI.
284f5f9db   Bjorn Helgaas   PCI: work around ...
2286
2287
2288
  		pcie_scan_all	Scan all possible PCIe devices.  Otherwise we
  				only look for one device below a PCIe downstream
  				port.
6b4b78fed   Matt Domsch   PCI: optionally s...
2289

e5665a45f   Chuck Ebbert   PCI: document the...
2290
2291
2292
2293
2294
  	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.
7570a333d   MUNEDA Takahiro   PCI: Add pcie_hp=...
2295
2296
2297
  	pcie_hp=	[PCIE] PCI Express Hotplug driver options:
  		nomsi	Do not use MSI for PCI Express Native Hotplug (this
  			makes all PCIe ports use INTx for hotplug services).
79dd9182d   Rafael J. Wysocki   PCI: PCIe: Introd...
2298
  	pcie_ports=	[PCIE] PCIe ports handling:
28eb5f274   Rafael J. Wysocki   PCI: PCIe: Ask BI...
2299
2300
2301
2302
2303
  		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   Rafael J. Wysocki   PCI: PCIe: Introd...
2304
2305
  		compat	Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
  			ports driver.
c7f486567   Rafael J. Wysocki   PCI PM: PCIe PME ...
2306
  	pcie_pme=	[PCIE,PM] Native PCIe PME signaling options:
c39fae141   Rafael J. Wysocki   PCI PM: Make it p...
2307
  		nomsi	Do not use MSI for native PCIe PME signaling (this makes
28eb5f274   Rafael J. Wysocki   PCI: PCIe: Ask BI...
2308
  			all PCIe root ports use INTx for all services).
c7f486567   Rafael J. Wysocki   PCI PM: PCIe PME ...
2309

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2310
  	pcmv=		[HW,PCMCIA] BadgePAD 4
39ac5ba51   Tushar Behera   PM / domains: Add...
2311
2312
2313
2314
2315
2316
  	pd_ignore_unused
  			[PM]
  			Keep all power-domains already enabled by bootloader on,
  			even if no driver has claimed them. This is useful
  			for debug and development, but should not be
  			needed on a platform with proper driver support.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2317
  	pd.		[PARIDE]
31c00fc15   Randy Dunlap   Create/use more d...
2318
  			See Documentation/blockdev/paride.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2319
2320
2321
2322
2323
  
  	pdcchassis=	[PARISC,HW] Disable/Enable PDC Chassis Status codes at
  			boot time.
  			Format: { 0 | 1 }
  			See arch/parisc/kernel/pdc_chassis.c
f58dc01ba   Tejun Heo   percpu: generaliz...
2324
  	percpu_alloc=	Select which percpu first chunk allocator to use.
e933a73f4   Tejun Heo   percpu: kill lpag...
2325
2326
2327
2328
2329
  			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   Tejun Heo   x86: implement pe...
2330

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2331
  	pf.		[PARIDE]
31c00fc15   Randy Dunlap   Create/use more d...
2332
  			See Documentation/blockdev/paride.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2333
2334
  
  	pg.		[PARIDE]
31c00fc15   Randy Dunlap   Create/use more d...
2335
  			See Documentation/blockdev/paride.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2336
2337
  
  	pirq=		[SMP,APIC] Manual mp-table setup
71cced6eb   Uwe Hermann   doc/x86: fix doc ...
2338
  			See Documentation/x86/i386/IO-APIC.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2339
2340
2341
2342
  
  	plip=		[PPT,NET] Parallel port network link
  			Format: { parport<nr> | timid | 0 }
  			See also Documentation/parport.txt.
162902466   Randy Dunlap   Documentation: ke...
2343
  	pmtmr=		[X86] Manual setup of pmtmr I/O Port.
de32a2434   Thomas Gleixner   kernel-paramaters...
2344
2345
  			Override pmtimer IOPort with a hex value.
  			e.g. pmtmr=0x508
96242116d   Bjorn Helgaas   PNP: update pnp.d...
2346
2347
2348
2349
2350
2351
  	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   Bjorn Helgaas   PNP: add CONFIG_P...
2352

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
  	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   Randy Dunlap   [PATCH] kernel-pa...
2366
  			Ranges are in pairs (I/O port base and size).
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2367
2368
  
  	pnp_reserve_mem=
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2369
2370
  			[ISAPNP] Exclude memory regions for the
  			autoconfiguration.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2371
  			Ranges are in pairs (memory base and size).
4af94f390   Randy Dunlap   doc: fix kernel-p...
2372
2373
2374
2375
2376
  	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   Ingo Molnar   vdso: print fatal...
2377
2378
  	print-fatal-signals=
  			[KNL] debug: print fatal signals
f84d49b21   Naohiro Ooiwa   signal: Print war...
2379
2380
2381
2382
2383
2384
2385
2386
  
  			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   Ingo Molnar   vdso: print fatal...
2387
  			default: off.
c22ab3329   Matthew Garrett   kmsg_dump: don't ...
2388
2389
2390
2391
2392
  	printk.always_kmsg_dump=
  			Trigger kmsg_dump for cases other than kernel oops or
  			panics
  			Format: <bool>  (1/Y/y=enable, 0/N/n=disable)
  			default: disabled
e84845c4b   Randy Dunlap   add printk.time o...
2393
2394
  	printk.time=	Show timing data prefixed to each printk message line
  			Format: <bool>  (1/Y/y=enable, 0/N/n=disable)
0cb55ad2a   Randy Dunlap   docs: alphabetize...
2395
2396
2397
2398
2399
2400
2401
  	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   Linus Torvalds   Linux-2.6.12-rc2
2402
  	profile=	[KNL] Enable kernel profiling via /proc/profile
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2403
2404
2405
2406
  			Format: [schedule,]<number>
  			Param: "schedule" - profile schedule points.
  			Param: <number> - step/bucket size as a power of 2 for
  				statistical time based profiling.
b3da2a73f   Mel Gorman   sched: document p...
2407
2408
  			Param: "sleep" - profile D-state sleeping (millisecs).
  				Requires CONFIG_SCHEDSTATS
c0fe2e696   Dave Jones   Add missing profi...
2409
  			Param: "kvm" - profile VM exits.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2410

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2411
2412
  	prompt_ramdisk=	[RAM] List of RAM disks to prompt for floppy disk
  			before loading.
31c00fc15   Randy Dunlap   Create/use more d...
2413
  			See Documentation/blockdev/ramdisk.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2414

a99130449   Randy Dunlap   [PATCH] kernel-pa...
2415
2416
  	psmouse.proto=	[HW,MOUSE] Highest PS2 mouse protocol extension to
  			probe for; one of (bare|imps|exps|lifebook|any).
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2417
2418
  	psmouse.rate=	[HW,MOUSE] Set desired mouse report rate, in reports
  			per second.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2419
2420
  	psmouse.resetafter=	[HW,MOUSE]
  			Try to reset the device after so many bad packets
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2421
2422
2423
2424
  			(0 = never).
  	psmouse.resolution=
  			[HW,MOUSE] Set desired mouse resolution, in dpi.
  	psmouse.smartscroll=
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2425
  			[HW,MOUSE] Controls Logitech smartscroll autorepeat.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2426
  			0 = disabled, 1 = enabled (default).
dee28e72b   Matthew Garrett   pstore: Allow the...
2427
  	pstore.backend=	Specify the name of the pstore backend to use
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2428
  	pt.		[PARIDE]
31c00fc15   Randy Dunlap   Create/use more d...
2429
  			See Documentation/blockdev/paride.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2430

dc8c85871   Kay Sievers   PTY: add kernel p...
2431
2432
2433
  	pty.legacy_count=
  			[KNL] Number of legacy pty's. Overwrites compiled-in
  			default number.
7d2c502f1   Randy Dunlap   [PATCH] doc: fix ...
2434
  	quiet		[KNL] Disable most log messages
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2435

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2436
2437
2438
2439
  	r128=		[HW,DRM]
  
  	raid=		[HW,RAID]
  			See Documentation/md.txt.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2440
  	ramdisk_blocksize=	[RAM]
31c00fc15   Randy Dunlap   Create/use more d...
2441
  			See Documentation/blockdev/ramdisk.txt.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2442

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2443
  	ramdisk_size=	[RAM] Sizes of RAM disks in kilobytes
31c00fc15   Randy Dunlap   Create/use more d...
2444
  			See Documentation/blockdev/ramdisk.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2445

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2446
  	rcu_nocbs=	[KNL]
3fbfbf7a3   Paul E. McKenney   rcu: Add callback...
2447
2448
2449
  			In kernels built with CONFIG_RCU_NOCB_CPU=y, set
  			the specified list of CPUs to be no-callback CPUs.
  			Invocation of these CPUs' RCU callbacks will
a48898585   Paul E. McKenney   rcu: Distinguish ...
2450
2451
2452
2453
  			be offloaded to "rcuox/N" kthreads created for
  			that purpose, where "x" is "b" for RCU-bh, "p"
  			for RCU-preempt, and "s" for RCU-sched, and "N"
  			is the CPU number.  This reduces OS jitter on the
3fbfbf7a3   Paul E. McKenney   rcu: Add callback...
2454
2455
2456
  			offloaded CPUs, which can be useful for HPC and
  			real-time workloads.  It can also improve energy
  			efficiency for asymmetric multiprocessors.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2457
  	rcu_nocb_poll	[KNL]
3fbfbf7a3   Paul E. McKenney   rcu: Add callback...
2458
2459
2460
2461
2462
2463
2464
2465
2466
  			Rather than requiring that offloaded CPUs
  			(specified by rcu_nocbs= above) explicitly
  			awaken the corresponding "rcuoN" kthreads,
  			make these kthreads poll for callbacks.
  			This improves the real-time response for the
  			offloaded CPUs by relieving them of the need to
  			wake up the corresponding kthread, but degrades
  			energy efficiency by requiring that the kthreads
  			periodically wake up to do the polling.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2467
  	rcutree.blimit=	[KNL]
97e63f0ca   Paul E. McKenney   rcu: Fix formatti...
2468
2469
  			Set maximum number of finished RCU callbacks to
  			process in one batch.
21a1ea9eb   Dipankar Sarma   [PATCH] rcu batch...
2470

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2471
  	rcutree.rcu_fanout_leaf= [KNL]
f885b7f2b   Paul E. McKenney   rcu: Control RCU_...
2472
2473
2474
  			Increase the number of CPUs assigned to each
  			leaf rcu_node structure.  Useful for very large
  			systems.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2475
  	rcutree.jiffies_till_first_fqs= [KNL]
c0f4dfd4f   Paul E. McKenney   rcu: Make RCU_FAS...
2476
2477
2478
2479
  			Set delay from grace-period initialization to
  			first attempt to force quiescent states.
  			Units are jiffies, minimum value is zero,
  			and maximum value is HZ.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2480
  	rcutree.jiffies_till_next_fqs= [KNL]
c0f4dfd4f   Paul E. McKenney   rcu: Make RCU_FAS...
2481
2482
2483
  			Set delay between subsequent attempts to force
  			quiescent states.  Units are jiffies, minimum
  			value is one, and maximum value is HZ.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2484
  	rcutree.qhimark= [KNL]
97e63f0ca   Paul E. McKenney   rcu: Fix formatti...
2485
2486
  			Set threshold of queued RCU callbacks beyond which
  			batch limiting is disabled.
21a1ea9eb   Dipankar Sarma   [PATCH] rcu batch...
2487

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2488
  	rcutree.qlowmark= [KNL]
24aaef8d7   Robert P. J. Day   Documentation: U...
2489
2490
  			Set threshold of queued RCU callbacks below which
  			batch limiting is re-enabled.
21a1ea9eb   Dipankar Sarma   [PATCH] rcu batch...
2491

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2492
  	rcutree.rcu_idle_gp_delay= [KNL]
c0f4dfd4f   Paul E. McKenney   rcu: Make RCU_FAS...
2493
2494
  			Set wakeup interval for idle CPUs that have
  			RCU callbacks (RCU_FAST_NO_HZ=y).
d40011f60   Paul E. McKenney   rcu: Control grac...
2495

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2496
  	rcutree.rcu_idle_lazy_gp_delay= [KNL]
c0f4dfd4f   Paul E. McKenney   rcu: Make RCU_FAS...
2497
2498
2499
2500
  			Set wakeup interval for idle CPUs that have
  			only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
  			Lazy RCU callbacks are those which RCU can
  			prove do nothing more than free memory.
d40011f60   Paul E. McKenney   rcu: Control grac...
2501

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2502
  	rcutorture.fqs_duration= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2503
  			Set duration of force_quiescent_state bursts.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2504
  	rcutorture.fqs_holdoff= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2505
  			Set holdoff time within force_quiescent_state bursts.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2506
  	rcutorture.fqs_stutter= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2507
  			Set wait time between force_quiescent_state bursts.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2508
2509
2510
2511
2512
2513
2514
2515
  	rcutorture.gp_exp= [KNL]
  			Use expedited update-side primitives.
  
  	rcutorture.gp_normal= [KNL]
  			Use normal (non-expedited) update-side primitives.
  			If both gp_exp and gp_normal are set, do both.
  			If neither gp_exp nor gp_normal are set, still
  			do both.
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2516

4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2517
  	rcutorture.n_barrier_cbs= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2518
  			Set callbacks/threads for rcu_barrier() testing.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2519
  	rcutorture.nfakewriters= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2520
2521
2522
  			Set number of concurrent RCU writers.  These just
  			stress RCU, they don't participate in the actual
  			test, hence the "fake".
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2523
  	rcutorture.nreaders= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2524
  			Set number of RCU readers.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2525
2526
2527
2528
  	rcutorture.object_debug= [KNL]
  			Enable debug-object double-call_rcu() testing.
  
  	rcutorture.onoff_holdoff= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2529
  			Set time (s) after boot for CPU-hotplug testing.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2530
  	rcutorture.onoff_interval= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2531
2532
  			Set time (s) between CPU-hotplug operations, or
  			zero to disable CPU-hotplug testing.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2533
2534
2535
2536
  	rcutorture.rcutorture_runnable= [BOOT]
  			Start rcutorture running at boot time.
  
  	rcutorture.shuffle_interval= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2537
2538
2539
  			Set task-shuffle interval (s).  Shuffling tasks
  			allows some CPUs to go into dyntick-idle mode
  			during the rcutorture test.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2540
  	rcutorture.shutdown_secs= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2541
2542
  			Set time (s) after boot system shutdown.  This
  			is useful for hands-off automated testing.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2543
  	rcutorture.stall_cpu= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2544
2545
  			Duration of CPU stall (s) to test RCU CPU stall
  			warnings, zero to disable.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2546
  	rcutorture.stall_cpu_holdoff= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2547
  			Time to wait (s) after boot before inducing stall.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2548
  	rcutorture.stat_interval= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2549
  			Time (s) between statistics printk()s.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2550
  	rcutorture.stutter= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2551
2552
2553
2554
  			Time (s) to stutter testing, for example, specifying
  			five seconds causes the test to run for five seconds,
  			wait for five seconds, and so on.  This tests RCU's
  			ability to transition abruptly to and from idle.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2555
  	rcutorture.test_boost= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2556
2557
2558
  			Test RCU priority boosting?  0=no, 1=maybe, 2=yes.
  			"Maybe" means test if the RCU implementation
  			under test support RCU priority boosting.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2559
  	rcutorture.test_boost_duration= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2560
  			Duration (s) of each individual boost test.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2561
  	rcutorture.test_boost_interval= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2562
  			Interval (s) between each boost test.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2563
  	rcutorture.test_no_idle_hz= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2564
2565
  			Test RCU's dyntick-idle handling.  See also the
  			rcutorture.shuffle_interval parameter.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2566
  	rcutorture.torture_type= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2567
  			Specify the RCU implementation to test.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2568
  	rcutorture.verbose= [KNL]
dabb8aa96   Paul E. McKenney   rcu: Document ker...
2569
  			Enable additional printk() statements.
4102adab9   Paul E. McKenney   rcu: Move RCU-rel...
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
  	rcupdate.rcu_expedited= [KNL]
  			Use expedited grace-period primitives, for
  			example, synchronize_rcu_expedited() instead
  			of synchronize_rcu().  This reduces latency,
  			but can increase CPU utilization, degrade
  			real-time latency, and degrade energy efficiency.
  
  	rcupdate.rcu_cpu_stall_suppress= [KNL]
  			Suppress RCU CPU stall warning messages.
  
  	rcupdate.rcu_cpu_stall_timeout= [KNL]
  			Set timeout for RCU CPU stall warning messages.
ffdfc4097   Olof Johansson   [PATCH] Add rdini...
2582
2583
2584
2585
  	rdinit=		[KNL]
  			Format: <full_path>
  			Run specified binary instead of /init from the ramdisk,
  			used for early userspace startup. See initrd.
1b3a5d02e   Robin Holt   reboot: move arch...
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
  	reboot=		[KNL]
  			Format (x86 or x86_64):
  				[w[arm] | c[old] | h[ard] | s[oft] | g[pio]] \
  				[[,]s[mp]#### \
  				[[,]b[ios] | a[cpi] | k[bd] | t[riple] | e[fi] | p[ci]] \
  				[[,]f[orce]
  			Where reboot_mode is one of warm (soft) or cold (hard) or gpio,
  			      reboot_type is one of bios, acpi, kbd, triple, efi, or pci,
  			      reboot_force is either force or not specified,
  			      reboot_cpu is s[mp]#### with #### being the processor
  					to be used for rebooting.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2597

46b6d94eb   Paul Jackson   doc: document the...
2598
2599
  	relax_domain_level=
  			[KNL, SMP] Set scheduler's default relax_domain_level.
21acb9caa   Thadeu Lima de Souza Cascardo   trivial: fix wher...
2600
  			See Documentation/cgroups/cpusets.txt.
46b6d94eb   Paul Jackson   doc: document the...
2601

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2602
  	reserve=	[KNL,BUGS] Force the kernel to ignore some iomem area
cd4f0ef7c   Alan Cox   doc/kernel-parame...
2603
  	reservetop=	[X86-32]
461a9afff   Zachary Amsden   [PATCH] x86: add ...
2604
2605
2606
  			Format: nn[KMG]
  			Reserves a hole at the top of the kernel virtual
  			address space.
9ea77bdb3   H. Peter Anvin   x86, bios: Make t...
2607
2608
2609
2610
  	reservelow=	[X86]
  			Format: nn[K]
  			Set the amount of memory to reserve for BIOS at
  			the bottom of the address space.
7e96287dd   Vivek Goyal   [PATCH] kdump: in...
2611
2612
  	reset_devices	[KNL] Force drivers to reset the underlying device
  			during initialization.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2613
2614
  	resume=		[SWSUSP]
  			Specify the partition device for software suspend
2df83fa4b   Minho Ban   PM / Hibernate: U...
2615
2616
  			Format:
  			{/dev/<dev> | PARTUUID=<uuid> | <int>:<int> | <hex>}
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2617

ecbd0da1e   Rafael J. Wysocki   [PATCH] swsusp: d...
2618
2619
2620
2621
2622
  	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
f126f7334   Barry Song   PM / Hibernate: A...
2623
2624
  	resumedelay=	[HIBERNATION] Delay (in seconds) to pause before attempting to
  			read the resume files
6f8d7022a   Barry Song   PM / Hibernate: A...
2625
2626
2627
  	resumewait	[HIBERNATION] Wait (indefinitely) for resume device to show up.
  			Useful for devices that are detected asynchronously
  			(e.g. USB and MMC devices).
f996fc967   Bojan Smojver   PM / Hibernate: C...
2628
2629
2630
2631
  	hibernate=	[HIBERNATION]
  		noresume	Don't check if there's a hibernation image
  				present during boot.
  		nocompress	Don't compress/decompress hibernation images.
0a7b35cb1   Michael Neuling   [PATCH] Add retai...
2632
  	retain_initrd	[RAM] Keep initrd memory after extraction
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2633
2634
  	rhash_entries=	[KNL,NET]
  			Set number of hash buckets for route cache
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2635
2636
2637
  	ro		[KNL] Mount root device read-only on boot
  
  	root=		[KNL] Root filesystem
f2d34fd94   Will Drewry   Documentation: ad...
2638
  			See name_to_dev_t comment in init/do_mounts.c.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2639
2640
2641
2642
2643
2644
2645
  
  	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   Pierre Ossman   init: wait for as...
2646
2647
2648
  	rootwait	[KNL] Wait (indefinitely) for root device to show up.
  			Useful for devices that are detected asynchronously
  			(e.g. USB and MMC devices).
5c71d6181   Robert Tivy   ARM: davinci: da8...
2649
2650
2651
2652
  	rproc_mem=nn[KMG][@address]
  			[KNL,ARM,CMA] Remoteproc physical memory block.
  			Memory area to be used by remote processor image,
  			managed by CMA.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2653
2654
2655
2656
2657
2658
  	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   Linus Torvalds   Linux-2.6.12-rc2
2659
  	sbni=		[NET] Granch SBNI12 leased line adapter
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2660

f6630114d   Mike Travis   sched: Limit the ...
2661
  	sched_debug	[KNL] Enables verbose scheduler debug messages.
5307c9556   Mike Galbraith   tick: Add tick sk...
2662
2663
2664
2665
2666
2667
2668
2669
  	skew_tick=	[KNL] Offset the periodic timer tick per cpu to mitigate
  			xtime_lock contention on larger systems, and/or RCU lock
  			contention on all systems with CONFIG_MAXSMP set.
  			Format: { "0" | "1" }
  			0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
  			1 -- enable.
  			Note: increases power consumption, thus should only be
  			enabled if running jitter sensitive (HPC/RT) workloads.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
2670
2671
2672
2673
2674
2675
2676
  	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   Linus Torvalds   Linux-2.6.12-rc2
2677
2678
2679
2680
2681
2682
2683
  			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   John Johansen   AppArmor: update ...
2684
2685
2686
2687
2688
2689
  	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   Alan Cox   doc/kernel-parame...
2690
  	serialnumber	[BUGS=X86-32]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2691

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2692
2693
  	shapers=	[NET]
  			Maximal number of shapers.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2694

b05f78f5c   Yinghai Lu   x86_64: printout ...
2695
2696
2697
2698
2699
  	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   Linus Torvalds   Linux-2.6.12-rc2
2700
2701
  	simeth=		[IA-64]
  	simscsi=
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2702

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2703
  	slram=		[HW,MTD]
3df1cccdf   David Rientjes   slab: introduce s...
2704
2705
2706
2707
2708
  	slab_max_order=	[MM, SLAB]
  			Determines the maximum allowed order for slabs.
  			A high setting may cause OOMs due to memory
  			fragmentation.  Defaults to 1 for systems with
  			more than 32MB of RAM, 0 otherwise.
f0630fff5   Christoph Lameter   SLUB: support slu...
2709
2710
2711
2712
2713
2714
2715
  	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   Christoph Lameter   SLUB: More docume...
2716
2717
  
  	slub_max_order= [MM, SLUB]
f0630fff5   Christoph Lameter   SLUB: support slu...
2718
2719
2720
2721
  			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   Christoph Lameter   SLUB: More docume...
2722
2723
  
  	slub_min_objects=	[MM, SLUB]
f0630fff5   Christoph Lameter   SLUB: support slu...
2724
2725
2726
2727
2728
2729
  			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   Christoph Lameter   SLUB: More docume...
2730
2731
2732
  			For more information see Documentation/vm/slub.txt.
  
  	slub_min_order=	[MM, SLUB]
24775d652   Masanari Iida   Documentation: Fi...
2733
  			Determines the minimum page order for slabs. Must be
f0630fff5   Christoph Lameter   SLUB: support slu...
2734
  			lower than slub_max_order.
c1aee215d   Christoph Lameter   SLUB: More docume...
2735
2736
2737
  			For more information see Documentation/vm/slub.txt.
  
  	slub_nomerge	[MM, SLUB]
f0630fff5   Christoph Lameter   SLUB: support slu...
2738
  			Disable merging of slabs with similar size. May be
c1aee215d   Christoph Lameter   SLUB: More docume...
2739
  			necessary if there is some reason to distinguish
f0630fff5   Christoph Lameter   SLUB: support slu...
2740
2741
  			allocs to different slabs. Debug options disable
  			merging on their own.
c1aee215d   Christoph Lameter   SLUB: More docume...
2742
  			For more information see Documentation/vm/slub.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2743
2744
  	smart2=		[HW]
  			Format: <io1>[,<io2>[,...,<io8>]]
d0d4f69bb   Bjorn Helgaas   smsc-ircc2: add P...
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
  	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   Ingo Molnar   softlockup: allow...
2755
2756
  	softlockup_panic=
  			[KNL] Should the soft-lockup detector generate panics.
44a4dcf75   Randy Dunlap   Documentation: up...
2757
  			Format: <integer>
9c44bc03f   Ingo Molnar   softlockup: allow...
2758

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2759
  	sonypi.*=	[HW] Sony Programmable I/O Control Device driver
395cf9691   Paul Bolle   doc: fix broken r...
2760
  			See Documentation/laptops/sonypi.txt
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2761

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2762
2763
2764
2765
  	spia_io_base=	[HW,MTD]
  	spia_fio_base=
  	spia_pedr=
  	spia_peddr=
f38f1d2aa   Steven Rostedt   trace: add a way ...
2766
2767
  	stacktrace	[FTRACE]
  			Enabled the stack tracer on boot up.
762e12078   Steven Rostedt   tracing: Have sta...
2768
2769
2770
2771
2772
2773
2774
  	stacktrace_filter=[function-list]
  			[FTRACE] Limit the functions that the stack tracer
  			will trace at boot up. function-list is a comma separated
  			list of functions. This list can be changed at run
  			time by the stack_trace_filter file in the debugfs
  			tracing directory. Note, this enables stack tracing
  			and the stacktrace above is not needed.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
  	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   Trond Myklebust   SUNRPC: convert s...
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
  	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   Greg Banks   [PATCH] knfsd: pr...
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
  	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   Trond Myklebust   SUNRPC: convert s...
2813
2814
2815
2816
2817
2818
2819
2820
  	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.
07555ac14   Michal Hocko   memcg: get rid of...
2821
  	swapaccount=[0|1]
a42c390cf   Michal Hocko   cgroups: make swa...
2822
2823
2824
  			[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)
91fec0f56   Jiri Kosina   swiotlb: update f...
2825
2826
2827
2828
2829
  	swiotlb=	[ARM,IA-64,PPC,MIPS,X86]
  			Format: { <int> | force }
  			<int> -- Number of I/O TLB slabs
  			force -- force using of bounce buffers even if they
  			         wouldn't be automatically used by the kernel
a99130449   Randy Dunlap   [PATCH] kernel-pa...
2830

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2831
  	switches=	[HW,M68k]
e52eec13c   Andi Kleen   SYSFS: Allow boot...
2832
2833
2834
2835
2836
2837
2838
2839
  	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   Ingo Molnar   [PATCH] debug: ad...
2840
2841
2842
2843
2844
  	sysrq_always_enabled
  			[KNL]
  			Ignore sysrq setting - this boot parameter will
  			neutralize any effect of /proc/sys/kernel/sysrq.
  			Useful for debugging.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2845
  	tdfx=		[HW,DRM]
77437fd4e   David Brownell   pm: boot time sus...
2846
2847
2848
2849
2850
  	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   Linus Torvalds   Linux-2.6.12-rc2
2851
2852
  	thash_entries=	[KNL,NET]
  			Set number of hash buckets for TCP connection
f8707ec96   Len Brown   ACPI: thermal: cr...
2853
2854
2855
  	thermal.act=	[HW,ACPI]
  			-1: disable all active trip points in all thermal zones
  			<degrees C>: override all lowest active trip points
c52a7419a   Len Brown   ACPI: thermal: cr...
2856
2857
  	thermal.crt=	[HW,ACPI]
  			-1: disable all critical trip points in all thermal zones
22a94d79a   Zhang Rui   ACPI: Allow overr...
2858
  			<degrees C>: override all critical trip points
c52a7419a   Len Brown   ACPI: thermal: cr...
2859

f54871456   Len Brown   ACPI: thermal: cr...
2860
2861
2862
  	thermal.nocrt=	[HW,ACPI]
  			Set to disable actions on ACPI thermal zone
  			critical and hot trip points.
72b33ef8b   Len Brown   ACPI: thermal: cr...
2863
2864
  	thermal.off=	[HW,ACPI]
  			1: disable ACPI thermal control
a70cdc520   Len Brown   ACPI: thermal: cr...
2865
2866
  	thermal.psv=	[HW,ACPI]
  			-1: disable all passive trip points
ada9cfdd1   Randy Dunlap   doc: fix kernel-p...
2867
2868
  			<degrees C>: override all passive trip points to this
  			value
a70cdc520   Len Brown   ACPI: thermal: cr...
2869

730ff34de   Len Brown   ACPI: thermal: ex...
2870
2871
2872
2873
  	thermal.tzp=	[HW,ACPI]
  			Specify global default ACPI thermal zone polling rate
  			<deci-seconds>: poll all this frequency
  			0: no polling (default)
8d32a307e   Thomas Gleixner   genirq: Provide f...
2874
2875
  	threadirqs	[KNL]
  			Force threading of all interrupt handlers except those
24775d652   Masanari Iida   Documentation: Fi...
2876
  			marked explicitly IRQF_NO_THREAD.
8d32a307e   Thomas Gleixner   genirq: Provide f...
2877

2ca62b044   Konrad Rzeszutek Wilk   xen/tmem: Remove ...
2878
2879
2880
2881
2882
2883
2884
2885
2886
  	tmem		[KNL,XEN]
  			Enable the Transcendent memory driver if built-in.
  
  	tmem.cleancache=0|1 [KNL, XEN]
  			Default is on (1). Disable the usage of the cleancache
  			API to send anonymous pages to the hypervisor.
  
  	tmem.frontswap=0|1 [KNL, XEN]
  			Default is on (1). Disable the usage of the frontswap
37d46e152   Konrad Rzeszutek Wilk   xen/tmem: Don't u...
2887
2888
  			API to send swap pages to the hypervisor. If disabled
  			the selfballooning and selfshrinking are force disabled.
2ca62b044   Konrad Rzeszutek Wilk   xen/tmem: Remove ...
2889
2890
2891
2892
2893
2894
2895
2896
2897
  
  	tmem.selfballooning=0|1 [KNL, XEN]
  			Default is on (1). Disable the driving of swap pages
  			to the hypervisor.
  
  	tmem.selfshrinking=0|1 [KNL, XEN]
  			Default is on (1). Partial swapoff that immediately
  			transfers pages from Xen hypervisor back to the
  			kernel based on different criteria.
2b1a61f0a   Heiko Carstens   [S390] cpu topolo...
2898
2899
2900
  	topology=	[S390]
  			Format: {off | on}
  			Specify if the kernel should make use of the cpu
f65e51d74   Sylvestre Ledru   Documentation: fi...
2901
2902
  			topology information if the hardware supports this.
  			The scheduler will make use of this information and
2b1a61f0a   Heiko Carstens   [S390] cpu topolo...
2903
  			e.g. base its process migration decisions on it.
c9af3fa9e   Heiko Carstens   [S390] topology: ...
2904
  			Default is on.
2b1a61f0a   Heiko Carstens   [S390] cpu topolo...
2905

1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2906
  	tp720=		[HW,PS2]
225a9be24   Rajiv Andrade   TPM: workaround t...
2907
2908
2909
2910
2911
2912
2913
2914
  	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   Li Zefan   tracing: Fix trac...
2915
2916
  	trace_buf_size=nn[KMG]
  			[FTRACE] will set tracing buffer size.
631595fbf   KOSAKI Motohiro   doc: add trace_bu...
2917

020e5f85c   Li Zefan   tracing/events: A...
2918
2919
2920
2921
  	trace_event=[event-list]
  			[FTRACE] Set and start specified trace events in order
  			to facilitate early boot debugging.
  			See also Documentation/trace/events.txt
7bcfaf54f   Steven Rostedt   tracing: Add trac...
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
  	trace_options=[option-list]
  			[FTRACE] Enable or disable tracer options at boot.
  			The option-list is a comma delimited list of options
  			that can be enabled or disabled just as if you were
  			to echo the option name into
  
  			    /sys/kernel/debug/tracing/trace_options
  
  			For example, to enable stacktrace option (to dump the
  			stack trace of each event), add to the command line:
  
  			      trace_options=stacktrace
  
  			See also Documentation/trace/ftrace.txt "trace options"
  			section.
de7edd314   Steven Rostedt (Red Hat)   tracing: Disable ...
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
  	traceoff_on_warning
  			[FTRACE] enable this option to disable tracing when a
  			warning is hit. This turns off "tracing_on". Tracing can
  			be enabled again by echoing '1' into the "tracing_on"
  			file located in /sys/kernel/debug/tracing/
  
  			This option is useful, as it disables the trace before
  			the WARNING dump is called, which prevents the trace to
  			be filled with content caused by the warning output.
  
  			This option can also be set at run time via the sysctl
  			option:  kernel/traceoff_on_warning
fcf4d8212   Jiri Kosina   thp: documentatio...
2949
2950
2951
2952
2953
2954
  	transparent_hugepage=
  			[KNL]
  			Format: [always|madvise|never]
  			Can be used to control the default behavior of the system
  			with respect to transparent hugepages.
  			See Documentation/vm/transhuge.txt for more details.
d3b8f889a   John Stultz   x86: Make tsc=rel...
2955
  	tsc=		Disable clocksource stability checks for TSC.
395628ef4   Alok Kataria   x86: Skip verific...
2956
2957
  			Format: <string>
  			[x86] reliable: mark tsc clocksource as reliable, this
d3b8f889a   John Stultz   x86: Make tsc=rel...
2958
2959
2960
2961
  			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   Venkatesh Pallipadi   x86: Add IRQ_TIME...
2962
2963
2964
2965
  			[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   Alok Kataria   x86: Skip verific...
2966

a99130449   Randy Dunlap   [PATCH] kernel-pa...
2967
2968
2969
2970
  	turbografx.map[2|3]=	[HW,JOY]
  			TurboGraFX parallel port interface
  			Format:
  			<port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
2971
  			See also Documentation/input/joystick-parport.txt
b6935f8cd   Christian Kujau   Document powerpc ...
2972
2973
2974
2975
  	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   Eric Dumazet   udp: dynamically ...
2976
2977
  	uhash_entries=	[KNL,NET]
  			Set number of hash buckets for UDP/UDP-Lite connections
5f8364b7d   Alan Stern   UHCI: module para...
2978
2979
2980
2981
2982
2983
2984
  	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   Simon Arlott   x86: add unknown_...
2985
  	unknown_nmi_panic
44a4dcf75   Randy Dunlap   Documentation: up...
2986
  			[X86] Cause panic on unknown NMI.
e3a61b0a8   Simon Arlott   x86: add unknown_...
2987

c4fc2342c   Carl-Daniel Hailfinger   USB: Add "authori...
2988
2989
2990
2991
  	usbcore.authorized_default=
  			[USB] Default USB device authorization:
  			(default -1 = authorized except for wireless USB,
  			0 = not authorized, 1 = authorized)
b5e795f8d   Alan Stern   USB: make autosus...
2992
2993
2994
2995
2996
  	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   Alan Stern   USB: Allow autosu...
2997
  			to a negative value won't be autosuspended at all.
b5e795f8d   Alan Stern   USB: make autosus...
2998

fd7c519dd   Jaroslav Kysela   USB: hub.c: Add i...
2999
3000
3001
3002
3003
3004
3005
3006
3007
  	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).
3f5eb8d56   Alan Stern   USB: make the usb...
3008
3009
3010
  	usbcore.usbfs_memory_mb=
  			[USB] Memory limit (in MB) for buffers allocated by
  			usbfs (default = 16, 0 = max = 2047).
fd7c519dd   Jaroslav Kysela   USB: hub.c: Add i...
3011
3012
3013
3014
3015
3016
3017
3018
  	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   Linus Torvalds   Linux-2.6.12-rc2
3019
3020
  	usbhid.mousepoll=
  			[USBHID] The interval which mice are to be polled at.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
3021

d4f373e57   Alan Stern   USB: usb-storage:...
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
  	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   Alan Stern   USB: storage: mak...
3034
3035
  				a = SANE_SENSE (collect more than 18 bytes
  					of sense data);
a0bb10811   Alan Stern   USB: usb-storage:...
3036
3037
  				b = BAD_SENSE (don't collect more than 18
  					bytes of sense data);
d4f373e57   Alan Stern   USB: usb-storage:...
3038
3039
  				c = FIX_CAPACITY (decrease the reported
  					device capacity by one sector);
5116901d8   Karl Relton   usb-storage: Corr...
3040
3041
3042
3043
  				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   Alan Stern   USB: storage: mak...
3044
3045
3046
  				h = CAPACITY_HEURISTICS (decrease the
  					reported device capacity by one
  					sector if the number is odd);
d4f373e57   Alan Stern   USB: usb-storage:...
3047
3048
3049
3050
3051
3052
  				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   Alan Stern   usb-storage: redo...
3053
3054
  				n = INITIAL_READ10 (force a retry of the
  					initial READ(10) command);
c838ea462   Alan Stern   USB: storage: mak...
3055
3056
  				o = CAPACITY_OK (accept the capacity
  					reported by the device);
eaa05dfcd   Namjae Jeon   [SCSI] usb-storag...
3057
3058
  				p = WRITE_CACHE (the device cache is ON
  					by default);
d4f373e57   Alan Stern   USB: usb-storage:...
3059
3060
3061
3062
3063
3064
3065
  				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   Stephen Boyd   Documentation: ad...
3066
3067
3068
3069
3070
3071
3072
3073
3074
  	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   Ian Campbell   x86, mm: Allow hi...
3075
3076
3077
3078
3079
3080
  	userpte=
  			[X86] Flags controlling user PTE allocations.
  
  				nohigh = do not allocate PTE pages in
  					HIGHMEM regardless of setting
  					of CONFIG_HIGHPTE.
6cececfce   Jaswinder Singh Rajput   x86, documentatio...
3081
  	vdso=		[X86,SH]
b0b49f267   Andy Lutomirski   x86, vdso: Remove...
3082
3083
3084
  			On X86_32, this is an alias for vdso32=.  Otherwise:
  
  			vdso=1: enable VDSO (the default)
e6e5494cb   Ingo Molnar   [PATCH] vdso: ran...
3085
  			vdso=0: disable VDSO mapping
b0b49f267   Andy Lutomirski   x86, vdso: Remove...
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
  	vdso32=		[X86] Control the 32-bit vDSO
  			vdso32=1: enable 32-bit VDSO
  			vdso32=0 or vdso32=2: disable 32-bit VDSO
  
  			See the help text for CONFIG_COMPAT_VDSO for more
  			details.  If CONFIG_COMPAT_VDSO is set, the default is
  			vdso32=0; otherwise, the default is vdso32=1.
  
  			For compatibility with older kernels, vdso32=2 is an
  			alias for vdso32=0.
  
  			Try vdso32=0 if you encounter an error that says:
  			dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
af65d6484   Roland McGrath   x86 vDSO: consoli...
3099

d080d397f   Yasuaki Ishimatsu   [IA64] Enable per...
3100
3101
  	vector=		[IA-64,SMP]
  			vector=percpu: enable percpu vector domain
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3102
3103
  	video=		[FB] Frame buffer configuration
  			See Documentation/fb/modedb.txt.
3afe6dab8   Aaron Lu   ACPI / video: add...
3104
3105
3106
3107
3108
3109
3110
3111
  	video.brightness_switch_enabled= [0,1]
  			If set to 1, on receiving an ACPI notify event
  			generated by hotkey, video driver will adjust brightness
  			level and then send out the event to user space through
  			the allocated input device; If set to 0, video driver
  			will only send out the event without touching backlight
  			brightness level.
  			default: 1
81a054ce0   Pawel Moll   virtio-mmio: Devi...
3112
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3119
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  	virtio_mmio.device=
  			[VMMIO] Memory mapped virtio (platform) device.
  
  				<size>@<baseaddr>:<irq>[:<id>]
  			where:
  				<size>     := size (can use standard suffixes
  						like K, M and G)
  				<baseaddr> := physical base address
  				<irq>      := interrupt number (as passed to
  						request_irq())
  				<id>       := (optional) platform device id
  			example:
  				virtio_mmio.device=1K@0x100b0000:48:7
  
  			Can be used multiple times for multiple devices.
cd4f0ef7c   Alan Cox   doc/kernel-parame...
3127
  	vga=		[BOOT,X86-32] Select a particular video mode
954a8b816   Kyle McMartin   x86, doc: fix ref...
3128
  			See Documentation/x86/boot.txt and
a99130449   Randy Dunlap   [PATCH] kernel-pa...
3129
  			Documentation/svga.txt.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3130
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3132
  			Use vga=ask for menu.
  			This is actually a boot loader parameter; the value is
  			passed to the kernel using a special protocol.
a99130449   Randy Dunlap   [PATCH] kernel-pa...
3133
  	vmalloc=nn[KMG]	[KNL,BOOT] Forces the vmalloc area to have an exact
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3134
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  			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   Peter Oberparleiter   [S390] Add vmpani...
3138
3139
  	vmhalt=		[KNL,S390] Perform z/VM CP command after system halt.
  			Format: <command>
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3140

585c3047a   Peter Oberparleiter   [S390] Add vmpani...
3141
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3145
  	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   Randy Dunlap   [PATCH] kernel-pa...
3146

3ae36655b   Andy Lutomirski   x86-64: Rework vs...
3147
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3153
  	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.
2e57ae051   Andy Lutomirski   x86: Default to v...
3154
3155
  			emulate     [default] Vsyscalls turn into traps and are
  			            emulated reasonably safely.
3ae36655b   Andy Lutomirski   x86-64: Rework vs...
3156

2e57ae051   Andy Lutomirski   x86: Default to v...
3157
  			native      Vsyscalls are native syscall instructions.
3ae36655b   Andy Lutomirski   x86-64: Rework vs...
3158
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  			            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.
3855ae1c4   Clemens Ladisch   vt: make the defa...
3166
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  	vt.color=	[VT] Default text color.
  			Format: 0xYX, X = foreground, Y = background.
  			Default: 0x07 = light gray on black.
9ea9a886b   Clemens Ladisch   vt: make the defa...
3169
3170
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3172
  	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   Randy Dunlap   docs: alphabetize...
3173
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3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
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  	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   Matthew Garrett   vc: Add support f...
3197
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3199
3200
3201
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3204
  	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.
3855ae1c4   Clemens Ladisch   vt: make the defa...
3205
3206
3207
3208
3209
  	vt.italic=	[VT] Default color for italic text; 0-15.
  			Default: 2 = green.
  
  	vt.underline=	[VT] Default color for underlined text; 0-15.
  			Default: 3 = cyan.
4724ba575   Randy Dunlap   watchdog: update/...
3210
3211
3212
3213
  	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   Linus Torvalds   Linux-2.6.12-rc2
3214

d55262c4d   Tejun Heo   workqueue: update...
3215
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3218
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3220
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3222
  	workqueue.disable_numa
  			By default, all work items queued to unbound
  			workqueues are affine to the NUMA nodes they're
  			issued on, which results in better behavior in
  			general.  If NUMA affinity needs to be disabled for
  			whatever reason, this option can be used.  Note
  			that this also can be controlled per-workqueue for
  			workqueues visible under /sys/bus/workqueue/.
cee22a150   Viresh Kumar   workqueues: Intro...
3223
3224
3225
3226
3227
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3230
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3234
3235
3236
  	workqueue.power_efficient
  			Per-cpu workqueues are generally preferred because
  			they show better performance thanks to cache
  			locality; unfortunately, per-cpu workqueues tend to
  			be more power hungry than unbound workqueues.
  
  			Enabling this makes the per-cpu workqueues which
  			were observed to contribute significantly to power
  			consumption unbound, leading to measurably lower
  			power usage at the cost of small performance
  			overhead.
  
  			The default value of this parameter is determined by
  			the config option CONFIG_WQ_POWER_EFFICIENT_DEFAULT.
0cb55ad2a   Randy Dunlap   docs: alphabetize...
3237
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3239
  	x2apic_phys	[X86-64,APIC] Use x2apic physical mode instead of
  			default x2apic cluster mode on platforms
  			supporting x2apic.
712b6aa87   Kuppuswamy Sathyanarayanan   intel_mid: Rename...
3240
3241
  	x86_intel_mid_timer= [X86-32,APBT]
  			Choose timer option for x86 Intel MID platform.
bb24c4716   Jacob Pan   x86, apbt: Moores...
3242
3243
  			Two valid options are apbt timer only and lapic timer
  			plus one apbt timer for broadcast timer.
712b6aa87   Kuppuswamy Sathyanarayanan   intel_mid: Rename...
3244
  			x86_intel_mid_timer=apbt_only | lapic_and_apbt
bb24c4716   Jacob Pan   x86, apbt: Moores...
3245

c1c5413ad   Stefano Stabellini   x86: Unplug emula...
3246
3247
3248
3249
3250
3251
3252
  	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   Ian Campbell   xen: pvhvm: renam...
3253
3254
3255
  			unnecessary -- unplugging emulated devices is
  				unnecessary even if the host did not respond to
  				the unplug protocol
c93a4dfb3   Ian Campbell   xen: pvhvm: allow...
3256
  			never -- do not unplug even if version check succeeds
c1c5413ad   Stefano Stabellini   x86: Unplug emula...
3257

15a3eac07   Konrad Rzeszutek Wilk   xen/spinlock: Doc...
3258
3259
3260
  	xen_nopvspin	[X86,XEN]
  			Disables the ticketlock slowpath using Xen PV
  			optimizations.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3261
  	xirc2ps_cs=	[NET,PCMCIA]
a99130449   Randy Dunlap   [PATCH] kernel-pa...
3262
3263
  			Format:
  			<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3264

a99130449   Randy Dunlap   [PATCH] kernel-pa...
3265
  ______________________________________________________________________
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3266
3267
  
  TODO:
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
3268
  	Add more DRM drivers.