X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=Documentation%2Fadmin-guide%2Fkernel-parameters.txt;h=81d1d5a7472804e50a663480ef92dc67abc71ab5;hb=4b783dd6a4071e0919fa7556462d86a792f518fc;hp=4cdcd1a1bbc3445fab39be8332950a854dd74bfd;hpb=bfd93a87eadb03499a5ff02dfebfaf515310d27c;p=linux

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4cdcd1a1bbc3..81d1d5a74728 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1068,7 +1068,7 @@
 			earlyprintk=serial[,0x...[,baudrate]]
 			earlyprintk=ttySn[,baudrate]
 			earlyprintk=dbgp[debugController#]
-			earlyprintk=pciserial,bus:device.function[,baudrate]
+			earlyprintk=pciserial[,force],bus:device.function[,baudrate]
 			earlyprintk=xdbc[xhciController#]
 
 			earlyprintk is useful when the kernel crashes before
@@ -1100,6 +1100,10 @@
 
 			The sclp output can only be used on s390.
 
+			The optional "force" to "pciserial" enables use of a
+			PCI device even when its classcode is not of the
+			UART class.
+
 	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
@@ -1759,12 +1763,24 @@
 		nobypass	[PPC/POWERNV]
 			Disable IOMMU bypass, using IOMMU for PCI devices.
 
+	iommu.strict=	[ARM64] Configure TLB invalidation behaviour
+			Format: { "0" | "1" }
+			0 - Lazy mode.
+			  Request that DMA unmap operations use deferred
+			  invalidation of hardware TLBs, for increased
+			  throughput at the cost of reduced device isolation.
+			  Will fall back to strict mode if not supported by
+			  the relevant IOMMU driver.
+			1 - Strict mode (default).
+			  DMA unmap operations invalidate IOMMU hardware TLBs
+			  synchronously.
+
 	iommu.passthrough=
 			[ARM64] Configure DMA to bypass the IOMMU by default.
 			Format: { "0" | "1" }
 			0 - Use IOMMU translation for DMA.
 			1 - Bypass the IOMMU for DMA.
-			unset - Use IOMMU translation for DMA.
+			unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
 
 	io7=		[HW] IO7 for Marvel based alpha systems
 			See comment before marvel_specify_io7 in
@@ -2416,7 +2432,7 @@
 			seconds.  Use this parameter to check at some
 			other rate.  0 disables periodic checking.
 
-	memtest=	[KNL,X86,ARM] Enable memtest
+	memtest=	[KNL,X86,ARM,PPC] Enable memtest
 			Format: <integer>
 			default : 0 <disable>
 			Specifies the number of memtest passes to be
@@ -4623,7 +4639,8 @@
 
 	usbcore.old_scheme_first=
 			[USB] Start with the old device initialization
-			scheme (default 0 = off).
+			scheme,  applies only to low and full-speed devices
+			 (default 0 = off).
 
 	usbcore.usbfs_memory_mb=
 			[USB] Memory limit (in MB) for buffers allocated by
@@ -4838,6 +4855,18 @@
 			This is actually a boot loader parameter; the value is
 			passed to the kernel using a special protocol.
 
+	vm_debug[=options]	[KNL] Available with CONFIG_DEBUG_VM=y.
+			May slow down system boot speed, especially when
+			enabled on systems with a large amount of memory.
+			All options are enabled by default, and this
+			interface is meant to allow for selectively
+			enabling or disabling specific virtual memory
+			debugging features.
+
+			Available options are:
+			  P	Enable page structure init time poisoning
+			  -	Disable all of the above options
+
 	vmalloc=nn[KMG]	[KNL,BOOT] Forces the vmalloc area to have an exact
 			size of <nn>. This can be used to increase the
 			minimum size (128MB on x86). It can also be used to