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  • 				assigned automatically to PCI devices. You can
    				make the kernel exclude IRQs of your ISA cards
    				this way.
    
    		pirqaddr=0xAAAAA	[X86] Specify the physical address
    
    				of the PIRQ table (normally generated
    				by the BIOS) if it is outside the
    				F0000h-100000h range.
    
    		lastbus=N	[X86] Scan all buses thru bus #N. Can be
    
    				useful if the kernel is unable to find your
    				secondary buses and you want to tell it
    				explicitly which ones they are.
    
    		assign-busses	[X86] Always assign all PCI bus
    
    				numbers ourselves, overriding
    				whatever the firmware may have done.
    
    		usepirqmask	[X86] Honor the possible IRQ mask stored
    
    				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.
    
    		noacpi		[X86] Do not use ACPI for IRQ routing
    
    				or for PCI scanning.
    
    		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.
    
    		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.
    
    		skip_isa_align	[X86] do not align io start addr, so can
    				handle more pci cards
    
    		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.
    
    		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.
    
    		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.
    
    		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.
    
    		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.
    
    		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.
    
    		realloc		reallocate PCI resources if allocations done by BIOS
    				are erroneous.
    
    	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.
    
    
    	pcie_ports=	[PCIE] PCIe ports handling:
    
    		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.
    
    		compat	Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
    			ports driver.
    
    
    	pcie_pme=	[PCIE,PM] Native PCIe PME signaling options:
    
    		nomsi	Do not use MSI for native PCIe PME signaling (this makes
    
    			all PCIe root ports use INTx for all services).
    
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    	pcmv=		[HW,PCMCIA] BadgePAD 4
    
    	pd.		[PARIDE]
    
    			See Documentation/blockdev/paride.txt.
    
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    	pdcchassis=	[PARISC,HW] Disable/Enable PDC Chassis Status codes at
    			boot time.
    			Format: { 0 | 1 }
    			See arch/parisc/kernel/pdc_chassis.c
    
    
    	percpu_alloc=	Select which percpu first chunk allocator to use.
    
    			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.
    
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    	pf.		[PARIDE]
    
    			See Documentation/blockdev/paride.txt.
    
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    	pg.		[PARIDE]
    
    			See Documentation/blockdev/paride.txt.
    
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    	pirq=		[SMP,APIC] Manual mp-table setup
    
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    			See Documentation/x86/i386/IO-APIC.txt.
    
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    	plip=		[PPT,NET] Parallel port network link
    			Format: { parport<nr> | timid | 0 }
    			See also Documentation/parport.txt.
    
    
    	pmtmr=		[X86] Manual setup of pmtmr I/O Port.
    
    			Override pmtimer IOPort with a hex value.
    			e.g. pmtmr=0x508
    
    
    	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.
    
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    	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
    
    			Ranges are in pairs (I/O port base and size).
    
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    	pnp_reserve_mem=
    
    			[ISAPNP] Exclude memory regions for the
    			autoconfiguration.
    
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    			Ranges are in pairs (memory base and size).
    
    
    	ports=		[IP_VS_FTP] IPVS ftp helper module
    			Default is 21.
    			Up to 8 (IP_VS_APP_MAX_PORTS) ports
    			may be specified.
    			Format: <port>,<port>....
    
    
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    	print-fatal-signals=
    			[KNL] debug: print fatal signals
    
    
    			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".
    
    
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    			default: off.
    
    
    	printk.time=	Show timing data prefixed to each printk message line
    			Format: <bool>  (1/Y/y=enable, 0/N/n=disable)
    
    
    	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
    
    
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    	profile=	[KNL] Enable kernel profiling via /proc/profile
    
    			Format: [schedule,]<number>
    			Param: "schedule" - profile schedule points.
    			Param: <number> - step/bucket size as a power of 2 for
    				statistical time based profiling.
    
    			Param: "sleep" - profile D-state sleeping (millisecs).
    				Requires CONFIG_SCHEDSTATS
    
    			Param: "kvm" - profile VM exits.
    
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    	prompt_ramdisk=	[RAM] List of RAM disks to prompt for floppy disk
    			before loading.
    
    			See Documentation/blockdev/ramdisk.txt.
    
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    	psmouse.proto=	[HW,MOUSE] Highest PS2 mouse protocol extension to
    			probe for; one of (bare|imps|exps|lifebook|any).
    
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    	psmouse.rate=	[HW,MOUSE] Set desired mouse report rate, in reports
    			per second.
    
    	psmouse.resetafter=	[HW,MOUSE]
    			Try to reset the device after so many bad packets
    
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    			(0 = never).
    	psmouse.resolution=
    			[HW,MOUSE] Set desired mouse resolution, in dpi.
    	psmouse.smartscroll=
    
    			[HW,MOUSE] Controls Logitech smartscroll autorepeat.
    
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    			0 = disabled, 1 = enabled (default).
    
    
    	pstore.backend=	Specify the name of the pstore backend to use
    
    
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    	pt.		[PARIDE]
    
    			See Documentation/blockdev/paride.txt.
    
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    	pty.legacy_count=
    			[KNL] Number of legacy pty's. Overwrites compiled-in
    			default number.
    
    
    	quiet		[KNL] Disable most log messages
    
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    	r128=		[HW,DRM]
    
    	raid=		[HW,RAID]
    			See Documentation/md.txt.
    
    
    	ramdisk_blocksize=	[RAM]
    
    			See Documentation/blockdev/ramdisk.txt.
    
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    	ramdisk_size=	[RAM] Sizes of RAM disks in kilobytes
    
    			See Documentation/blockdev/ramdisk.txt.
    
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    	rcupdate.blimit=	[KNL,BOOT]
    			Set maximum number of finished RCU callbacks to process
    			in one batch.
    
    	rcupdate.qhimark=	[KNL,BOOT]
    			Set threshold of queued
    
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    			RCU callbacks over which batch limiting is disabled.
    
    
    	rcupdate.qlowmark=	[KNL,BOOT]
    			Set threshold of queued RCU callbacks below which
    			batch limiting is re-enabled.
    
    	rdinit=		[KNL]
    			Format: <full_path>
    			Run specified binary instead of /init from the ramdisk,
    			used for early userspace startup. See initrd.
    
    
    	reboot=		[BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
    
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    			Format: <reboot_mode>[,<reboot_mode2>[,...]]
    
    			See arch/*/kernel/reboot.c or arch/*/kernel/process.c
    
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    	relax_domain_level=
    			[KNL, SMP] Set scheduler's default relax_domain_level.
    
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    	reserve=	[KNL,BUGS] Force the kernel to ignore some iomem area
    
    
    	reservetop=	[X86-32]
    
    			Format: nn[KMG]
    			Reserves a hole at the top of the kernel virtual
    			address space.
    
    
    	reservelow=	[X86]
    			Format: nn[K]
    			Set the amount of memory to reserve for BIOS at
    			the bottom of the address space.
    
    
    	reset_devices	[KNL] Force drivers to reset the underlying device
    			during initialization.
    
    
    	resume=		[SWSUSP]
    			Specify the partition device for software suspend
    
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    	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
    
    
    	resumedelay=	[HIBERNATION] Delay (in seconds) to pause before attempting to
    			read the resume files
    
    
    	resumewait	[HIBERNATION] Wait (indefinitely) for resume device to show up.
    			Useful for devices that are detected asynchronously
    			(e.g. USB and MMC devices).
    
    
    	hibernate=	[HIBERNATION]
    		noresume	Don't check if there's a hibernation image
    				present during boot.
    		nocompress	Don't compress/decompress hibernation images.
    
    
    	retain_initrd	[RAM] Keep initrd memory after extraction
    
    
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    	rhash_entries=	[KNL,NET]
    			Set number of hash buckets for route cache
    
    	riscom8=	[HW,SERIAL]
    			Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
    
    	ro		[KNL] Mount root device read-only on boot
    
    	root=		[KNL] Root filesystem
    
    			See name_to_dev_t comment in init/do_mounts.c.
    
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    	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
    
    
    	rootwait	[KNL] Wait (indefinitely) for root device to show up.
    			Useful for devices that are detected asynchronously
    			(e.g. USB and MMC devices).
    
    
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    	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.
    
    	sbni=		[NET] Granch SBNI12 leased line adapter
    
    	sched_debug	[KNL] Enables verbose scheduler debug messages.
    
    
    	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.
    
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    			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.
    
    
    	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.
    
    
    	serialnumber	[BUGS=X86-32]
    
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    	shapers=	[NET]
    			Maximal number of shapers.
    
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    	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.
    
    
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    	simeth=		[IA-64]
    	simscsi=
    
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    	slram=		[HW,MTD]
    
    
    	slub_debug[=options[,slabs]]	[MM, SLUB]
    			Enabling slub_debug allows one to determine the
    			culprit if slab objects become corrupted. Enabling
    			slub_debug can create guard zones around objects and
    			may poison objects when not in use. Also tracks the
    			last alloc / free. For more information see
    			Documentation/vm/slub.txt.
    
    
    	slub_max_order= [MM, SLUB]
    
    			Determines the maximum allowed order for slabs.
    			A high setting may cause OOMs due to memory
    			fragmentation. For more information see
    			Documentation/vm/slub.txt.
    
    
    	slub_min_objects=	[MM, SLUB]
    
    			The minimum number of objects per slab. SLUB will
    			increase the slab order up to slub_max_order to
    			generate a sufficiently large slab able to contain
    			the number of objects indicated. The higher the number
    			of objects the smaller the overhead of tracking slabs
    			and the less frequently locks need to be acquired.
    
    			For more information see Documentation/vm/slub.txt.
    
    	slub_min_order=	[MM, SLUB]
    			Determines the mininum page order for slabs. Must be
    
    			lower than slub_max_order.
    
    			For more information see Documentation/vm/slub.txt.
    
    	slub_nomerge	[MM, SLUB]
    
    			Disable merging of slabs with similar size. May be
    
    			necessary if there is some reason to distinguish
    
    			allocs to different slabs. Debug options disable
    			merging on their own.
    
    			For more information see Documentation/vm/slub.txt.
    
    
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    	smart2=		[HW]
    			Format: <io1>[,<io2>[,...,<io8>]]
    
    
    	smp-alt-once	[X86-32,SMP] On a hotplug CPU system, only
    
    			attempt to substitute SMP alternatives once at boot.
    
    
    	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
    
    
    	softlockup_panic=
    			[KNL] Should the soft-lockup detector generate panics.
    
    			Format: <integer>
    
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    	sonypi.*=	[HW] Sony Programmable I/O Control Device driver
    
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    			See Documentation/laptops/sonypi.txt
    
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    	specialix=	[HW,SERIAL] Specialix multi-serial port adapter
    
    			See Documentation/serial/specialix.txt.
    
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    	spia_io_base=	[HW,MTD]
    	spia_fio_base=
    	spia_pedr=
    	spia_peddr=
    
    
    	stacktrace	[FTRACE]
    			Enabled the stack tracer on boot up.
    
    
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    	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>...]]
    
    
    	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.
    
    
    	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)
    
    
    	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.
    
    
    	swapaccount[=0|1]
    			[KNL] Enable accounting of swap in memory resource
    			controller if no parameter or 1 is given or disable
    			it if 0 is given (See Documentation/cgroups/memory.txt)
    
    
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    	swiotlb=	[IA-64] Number of I/O TLB slabs
    
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    	switches=	[HW,M68k]
    
    
    	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.
    
    
    	sysrq_always_enabled
    			[KNL]
    			Ignore sysrq setting - this boot parameter will
    			neutralize any effect of /proc/sys/kernel/sysrq.
    			Useful for debugging.
    
    
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    	tdfx=		[HW,DRM]
    
    
    	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.
    
    
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    	thash_entries=	[KNL,NET]
    			Set number of hash buckets for TCP connection
    
    
    	thermal.act=	[HW,ACPI]
    			-1: disable all active trip points in all thermal zones
    			<degrees C>: override all lowest active trip points
    
    
    	thermal.crt=	[HW,ACPI]
    			-1: disable all critical trip points in all thermal zones
    
    			<degrees C>: override all critical trip points
    
    	thermal.nocrt=	[HW,ACPI]
    			Set to disable actions on ACPI thermal zone
    			critical and hot trip points.
    
    
    	thermal.off=	[HW,ACPI]
    			1: disable ACPI thermal control
    
    
    	thermal.psv=	[HW,ACPI]
    			-1: disable all passive trip points
    
    			<degrees C>: override all passive trip points to this
    			value
    
    	thermal.tzp=	[HW,ACPI]
    			Specify global default ACPI thermal zone polling rate
    			<deci-seconds>: poll all this frequency
    			0: no polling (default)
    
    
    	threadirqs	[KNL]
    			Force threading of all interrupt handlers except those
    			marked explicitely IRQF_NO_THREAD.
    
    
    	topology=	[S390]
    			Format: {off | on}
    			Specify if the kernel should make use of the cpu
    
    			topology information if the hardware supports this.
    			The scheduler will make use of this information and
    
    			e.g. base its process migration decisions on it.
    
    			Default is on.
    
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    	tp720=		[HW,PS2]
    
    
    	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.
    
    
    	trace_buf_size=nn[KMG]
    			[FTRACE] will set tracing buffer size.
    
    	trace_event=[event-list]
    			[FTRACE] Set and start specified trace events in order
    			to facilitate early boot debugging.
    			See also Documentation/trace/events.txt
    
    
    	tsc=		Disable clocksource stability checks for TSC.
    
    			Format: <string>
    			[x86] reliable: mark tsc clocksource as reliable, this
    
    			disables clocksource verification at runtime, as well
    			as the stability checks done at bootup.	Used to enable
    			high-resolution timer mode on older hardware, and in
    			virtualized environment.
    
    			[x86] noirqtime: Do not use TSC to do irq accounting.
    			Used to run time disable IRQ_TIME_ACCOUNTING on any
    			platforms where RDTSC is slow and this accounting
    			can add overhead.
    
    	turbografx.map[2|3]=	[HW,JOY]
    			TurboGraFX parallel port interface
    			Format:
    			<port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
    
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    			See also Documentation/input/joystick-parport.txt
    
    
    	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.
    
    
    	uhash_entries=	[KNL,NET]
    			Set number of hash buckets for UDP/UDP-Lite connections
    
    
    	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.
    
    
    	unknown_nmi_panic
    
    			[X86] Cause panic on unknown NMI.
    
    	usbcore.authorized_default=
    			[USB] Default USB device authorization:
    			(default -1 = authorized except for wireless USB,
    			0 = not authorized, 1 = authorized)
    
    
    	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
    
    			to a negative value won't be autosuspended at all.
    
    	usbcore.usbfs_snoop=
    			[USB] Set to log all usbfs traffic (default 0 = off).
    
    	usbcore.blinkenlights=
    			[USB] Set to cycle leds on hubs (default 0 = off).
    
    	usbcore.old_scheme_first=
    			[USB] Start with the old device initialization
    			scheme (default 0 = off).
    
    	usbcore.use_both_schemes=
    			[USB] Try the other device initialization scheme
    			if the first one fails (default 1 = enabled).
    
    	usbcore.initial_descriptor_timeout=
    			[USB] Specifies timeout for the initial 64-byte
                            USB_REQ_GET_DESCRIPTOR request in milliseconds
    			(default 5000 = 5.0 seconds).
    
    
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    	usbhid.mousepoll=
    			[USBHID] The interval which mice are to be polled at.
    
    	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:
    
    				a = SANE_SENSE (collect more than 18 bytes
    					of sense data);
    
    				b = BAD_SENSE (don't collect more than 18
    					bytes of sense data);
    
    				c = FIX_CAPACITY (decrease the reported
    					device capacity by one sector);
    
    				d = NO_READ_DISC_INFO (don't use
    					READ_DISC_INFO command);
    				e = NO_READ_CAPACITY_16 (don't use
    					READ_CAPACITY_16 command);
    
    				h = CAPACITY_HEURISTICS (decrease the
    					reported device capacity by one
    					sector if the number is odd);
    
    				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);
    
    				n = INITIAL_READ10 (force a retry of the
    					initial READ(10) command);
    
    				o = CAPACITY_OK (accept the capacity
    					reported by the device);
    
    				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
    
    
    	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
    
    
    	userpte=
    			[X86] Flags controlling user PTE allocations.
    
    				nohigh = do not allocate PTE pages in
    					HIGHMEM regardless of setting
    					of CONFIG_HIGHPTE.
    
    
    			vdso=2: enable compat VDSO (default with COMPAT_VDSO)
    
    			vdso=1: enable VDSO (default)
    			vdso=0: disable VDSO mapping
    
    
    			vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
    			vdso32=1: enable 32-bit VDSO (default)
    			vdso32=0: disable 32-bit VDSO mapping
    
    
    	vector=		[IA-64,SMP]
    			vector=percpu: enable percpu vector domain
    
    
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    	video=		[FB] Frame buffer configuration
    			See Documentation/fb/modedb.txt.
    
    
    	vga=		[BOOT,X86-32] Select a particular video mode
    
    			See Documentation/x86/boot.txt and
    
    			Documentation/svga.txt.
    
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    			Use vga=ask for menu.
    			This is actually a boot loader parameter; the value is
    			passed to the kernel using a special protocol.
    
    
    	vmalloc=nn[KMG]	[KNL,BOOT] Forces the vmalloc area to have an exact
    
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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.
    
    
    	vmhalt=		[KNL,S390] Perform z/VM CP command after system halt.
    			Format: <command>
    
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    	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>
    
    	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.
    
    
    			emulate     Vsyscalls turn into traps and are emulated
    			            reasonably safely.
    
    			native      [default] Vsyscalls are native syscall
    			            instructions.
    
    			            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.
    
    
    	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.
    
    
    	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.
    
    
    	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.
    
    
    	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.
    
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    	x2apic_phys	[X86-64,APIC] Use x2apic physical mode instead of
    			default x2apic cluster mode on platforms
    			supporting x2apic.
    
    
    	x86_mrst_timer= [X86-32,APBT]
    			Choose timer option for x86 Moorestown MID platform.
    			Two valid options are apbt timer only and lapic timer
    			plus one apbt timer for broadcast timer.
    			x86_mrst_timer=apbt_only | lapic_and_apbt
    
    
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    	xd=		[HW,XT] Original XT pre-IDE (RLL encoded) disks.
    	xd_geo=		See header of drivers/block/xd.c.
    
    
    	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)
    
    			unnecessary -- unplugging emulated devices is
    				unnecessary even if the host did not respond to
    				the unplug protocol
    
    			never -- do not unplug even if version check succeeds
    
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    	xirc2ps_cs=	[NET,PCMCIA]
    
    			Format:
    			<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
    
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    ______________________________________________________________________
    
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    TODO:
    
    	Add more DRM drivers.