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-rw-r--r--Documentation/kernel-parameters.txt106
1 files changed, 79 insertions, 27 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index a70e43edcb65..854ed5ca7e3f 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -40,6 +40,7 @@ parameter is applicable:
 	ALSA	ALSA sound support is enabled.
 	APIC	APIC support is enabled.
 	APM	Advanced Power Management support is enabled.
+	ARM	ARM architecture is enabled.
 	AVR32	AVR32 architecture is enabled.
 	AX25	Appropriate AX.25 support is enabled.
 	BLACKFIN Blackfin architecture is enabled.
@@ -49,6 +50,7 @@ parameter is applicable:
 	EFI	EFI Partitioning (GPT) is enabled
 	EIDE	EIDE/ATAPI support is enabled.
 	FB	The frame buffer device is enabled.
+	FTRACE	Function tracing enabled.
 	GCOV	GCOV profiling is enabled.
 	HW	Appropriate hardware is enabled.
 	IA-64	IA-64 architecture is enabled.
@@ -69,6 +71,7 @@ parameter is applicable:
 			Documentation/m68k/kernel-options.txt.
 	MCA	MCA bus support is enabled.
 	MDA	MDA console support is enabled.
+	MIPS	MIPS architecture is enabled.
 	MOUSE	Appropriate mouse support is enabled.
 	MSI	Message Signaled Interrupts (PCI).
 	MTD	MTD (Memory Technology Device) support is enabled.
@@ -100,7 +103,6 @@ parameter is applicable:
 	SPARC	Sparc architecture is enabled.
 	SWSUSP	Software suspend (hibernation) is enabled.
 	SUSPEND	System suspend states are enabled.
-	FTRACE	Function tracing enabled.
 	TPM	TPM drivers are enabled.
 	TS	Appropriate touchscreen support is enabled.
 	UMS	USB Mass Storage support is enabled.
@@ -115,7 +117,7 @@ parameter is applicable:
 	X86-64	X86-64 architecture is enabled.
 			More X86-64 boot options can be found in
 			Documentation/x86/x86_64/boot-options.txt .
-	X86	Either 32bit or 64bit x86 (same as X86-32+X86-64)
+	X86	Either 32-bit or 64-bit x86 (same as X86-32+X86-64)
 	XEN	Xen support is enabled
 
 In addition, the following text indicates that the option:
@@ -163,6 +165,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 			See also Documentation/power/pm.txt, pci=noacpi
 
+	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.
+
 	acpi_apic_instance=	[ACPI, IOAPIC]
 			Format: <int>
 			2: use 2nd APIC table, if available
@@ -371,7 +378,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 	atkbd.softrepeat= [HW]
 			Use software keyboard repeat
 
-	autotest	[IA64]
+	autotest	[IA-64]
 
 	baycom_epp=	[HW,AX25]
 			Format: <io>,<mode>
@@ -546,6 +553,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			/proc/<pid>/coredump_filter.
 			See also Documentation/filesystems/proc.txt.
 
+	cpuidle.off=1	[CPU_IDLE]
+			disable the cpuidle sub-system
+
 	cpcihp_generic=	[HW,PCI] Generic port I/O CompactPCI driver
 			Format:
 			<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
@@ -673,8 +683,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 		uart[8250],mmio32,<addr>[,options]
 			Start an early, polled-mode console on the 8250/16550
 			UART at the specified I/O port or MMIO address.
-			MMIO inter-register address stride is either 8bit (mmio)
-                        or 32bit (mmio32).
+			MMIO inter-register address stride is either 8-bit
+			(mmio) or 32-bit (mmio32).
 			The options are the same as for ttyS, above.
 
 	earlyprintk=	[X86,SH,BLACKFIN]
@@ -717,7 +727,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			See Documentation/block/as-iosched.txt and
 			Documentation/block/deadline-iosched.txt for details.
 
-	elfcorehdr=	[IA64,PPC,SH,X86]
+	elfcorehdr=	[IA-64,PPC,SH,X86]
 			Specifies physical address of start of kernel core
 			image elf header. Generally kexec loader will
 			pass this option to capture kernel.
@@ -783,7 +793,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			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
-			tracing directory. 
+			tracing directory.
 
 	ftrace_notrace=[function-list]
 			[FTRACE] Do not trace the functions specified in
@@ -821,7 +831,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	hashdist=	[KNL,NUMA] Large hashes allocated during boot
 			are distributed across NUMA nodes.  Defaults on
-			for 64bit NUMA, off otherwise.
+			for 64-bit NUMA, off otherwise.
 			Format: 0 | 1 (for off | on)
 
 	hcl=		[IA-64] SGI's Hardware Graph compatibility layer
@@ -990,10 +1000,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			DMA.
 		forcedac [x86_64]
 			With this option iommu will not optimize to look
-			for io virtual address below 32 bit forcing dual
+			for io virtual address below 32-bit forcing dual
 			address cycle on pci bus for cards supporting greater
-			than 32 bit addressing. The default is to look
-			for translation below 32 bit and if not available
+			than 32-bit addressing. The default is to look
+			for translation below 32-bit and if not available
 			then look in the higher range.
 		strict [Default Off]
 			With this option on every unmap_single operation will
@@ -1009,7 +1019,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			off	disable Interrupt Remapping
 			nosid	disable Source ID checking
 
-	inttest=	[IA64]
+	inttest=	[IA-64]
 
 	iomem=		Disable strict checking of access to MMIO memory
 		strict	regions from userspace.
@@ -1026,7 +1036,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 		nomerge
 		forcesac
 		soft
-		pt	[x86, IA64]
+		pt	[x86, IA-64]
 
 	io7=		[HW] IO7 for Marvel based alpha systems
 			See comment before marvel_specify_io7 in
@@ -1157,7 +1167,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	kvm-amd.npt=	[KVM,AMD] Disable nested paging (virtualized MMU)
 			for all guests.
-			Default is 1 (enabled) if in 64bit or 32bit-PAE mode
+			Default is 1 (enabled) if in 64-bit or 32-bit PAE mode.
 
 	kvm-intel.ept=	[KVM,Intel] Disable extended page tables
 			(virtualized MMU) support on capable Intel chips.
@@ -1194,10 +1204,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			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
-			libata.dma=4	  Compact Flash DMA only 
+			libata.dma=4	  Compact Flash DMA only
 			Combinations also work, so libata.dma=3 enables DMA
 			for disks and CDROMs, but not CFs.
-	
+
 	libata.ignore_hpa=	[LIBATA] Ignore HPA limit
 			libata.ignore_hpa=0	  keep BIOS limits (default)
 			libata.ignore_hpa=1	  ignore limits, using full disk
@@ -1323,7 +1333,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 	ltpc=		[NET]
 			Format: <io>,<irq>,<dma>
 
-	machvec=	[IA64] Force the use of a particular machine-vector
+	machvec=	[IA-64] Force the use of a particular machine-vector
 			(machvec) in a generic kernel.
 			Example: machvec=hpzx1_swiotlb
 
@@ -1340,9 +1350,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			it is equivalent to "nosmp", which also disables
 			the IO APIC.
 
-	max_loop=	[LOOP] Maximum number of loopback devices that can
-			be mounted
-			Format: <1-256>
+	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.
 
 	mcatest=	[IA-64]
 
@@ -1726,7 +1739,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	nointroute	[IA-64]
 
-	nojitter	[IA64] Disables jitter checking for ITC timers.
+	nojitter	[IA-64] Disables jitter checking for ITC timers.
 
 	no-kvmclock	[X86,KVM] Disable paravirtualized KVM clock driver
 
@@ -1792,7 +1805,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	nox2apic	[X86-64,APIC] Do not enable x2APIC mode.
 
-	nptcg=		[IA64] Override max number of concurrent global TLB
+	nptcg=		[IA-64] Override max number of concurrent global TLB
 			purges which is reported from either PAL_VM_SUMMARY or
 			SAL PALO.
 
@@ -1846,7 +1859,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			See Documentation/sound/oss/oss-parameters.txt
 
 	panic=		[KNL] Kernel behaviour on panic: delay <timeout>
-			seconds before rebooting
+			timeout > 0: seconds before rebooting
+			timeout = 0: wait forever
+			timeout < 0: reboot immediately
 			Format: <timeout>
 
 	parkbd.port=	[HW] Parallel port number the keyboard adapter is
@@ -2067,13 +2082,16 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			Format: { parport<nr> | timid | 0 }
 			See also Documentation/parport.txt.
 
-	pmtmr=		[X86] Manual setup of pmtmr I/O Port. 
+	pmtmr=		[X86] Manual setup of pmtmr I/O Port.
 			Override pmtimer IOPort with a hex value.
 			e.g. pmtmr=0x508
 
-	pnp.debug	[PNP]
-			Enable PNP debug messages.  This depends on the
-			CONFIG_PNP_DEBUG_MESSAGES option.
+	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.
 
 	pnpacpi=	[ACPI]
 			{ off }
@@ -2151,6 +2169,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			[HW,MOUSE] Controls Logitech smartscroll autorepeat.
 			0 = disabled, 1 = enabled (default).
 
+	pstore.backend=	Specify the name of the pstore backend to use
+
 	pt.		[PARIDE]
 			See Documentation/blockdev/paride.txt.
 
@@ -2236,6 +2256,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 	ro		[KNL] Mount root device read-only on boot
 
 	root=		[KNL] Root filesystem
+			See name_to_dev_t comment in init/do_mounts.c.
 
 	rootdelay=	[KNL] Delay (in seconds) to pause before attempting to
 			mount the root filesystem
@@ -2622,6 +2643,16 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 					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.
 
@@ -2667,6 +2698,27 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 	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     [default] Vsyscalls turn into traps and are
+			            emulated reasonably safely.
+
+			native      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;