Merge tag 'docs-4.9' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This is the documentation update pull for the 4.9 merge window.

  The Sphinx transition is still creating a fair amount of work. Here we
  have a number of fixes and, importantly, a proper PDF output solution,
  thanks to Jani Nikula, Mauro Carvalho Chehab and Markus Heiser.

  I've started a couple of new books: a driver API book (based on the
  old device-drivers.tmpl) and a development tools book. Both are meant
  to show how we can integrate together our existing documentation into
  a more coherent and accessible whole. It involves moving some stuff
  around and formatting changes, but, I think, the results are worth it.
  The good news is that most of our existing Documentation/*.txt files
  are *almost* in RST format already; the amount of messing around
  required is minimal.

  And, of course, there's the usual set of updates, typo fixes, and
  more"

* tag 'docs-4.9' of git://git.lwn.net/linux: (120 commits)
  URL changed for Linux Foundation TAB
  dax : Fix documentation with respect to struct pages
  iio: Documentation: Correct the path used to create triggers.
  docs: Remove space-before-label guidance from CodingStyle
  docs-rst: add inter-document cross references
  Documentation/email-clients.txt: convert it to ReST markup
  Documentation/kernel-docs.txt: reorder based on timestamp
  Documentation/kernel-docs.txt: Add dates for online docs
  Documentation/kernel-docs.txt: get rid of broken docs
  Documentation/kernel-docs.txt: move in-kernel docs
  Documentation/kernel-docs.txt: remove more legacy references
  Documentation/kernel-docs.txt: add two published books
  Documentation/kernel-docs.txt: sort books per publication date
  Documentation/kernel-docs.txt: adjust LDD references
  Documentation/kernel-docs.txt: some improvements on the ReST output
  Documentation/kernel-docs.txt: Consistent indenting: 4 spaces
  Documentation/kernel-docs.txt: Add 4 paper/book references
  Documentation/kernel-docs.txt: Improve layouting of book list
  Documentation/kernel-docs.txt: Remove offline or outdated entries
  docs: Clean up bare :: lines
  ...

1 files changed, 14 insertions, 10 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 01085cdc47c1..fcf05a07b06a 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1698,7 +1698,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	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.
+			1 to 9	specify maximum depth of C-state.
 
 	intel_pstate=  [X86]
 		       disable
@@ -2171,10 +2171,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			than or equal to this physical address is ignored.
 
 	maxcpus=	[SMP] Maximum number of processors that	an SMP kernel
-			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.
+			will bring up during bootup.  maxcpus=n : n >= 0 limits
+			the kernel to bring up 'n' processors. Surely after
+			bootup you can bring up the other plugged cpu by executing
+			"echo 1 > /sys/devices/system/cpu/cpuX/online". So maxcpus
+			only takes effect during system bootup.
+			While n=0 is a special case, it is equivalent to "nosmp",
+			which also disables the IO APIC.
 
 	max_loop=	[LOOP] The number of loop block devices that get
 	(loop.max_loop)	unconditionally pre-created at init time. The default
@@ -2581,8 +2584,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	nodelayacct	[KNL] Disable per-task delay accounting
 
-	nodisconnect	[HW,SCSI,M68K] Disables SCSI disconnects.
-
 	nodsp		[SH] Disable hardware DSP at boot time.
 
 	noefi		Disable EFI runtime services support.
@@ -2783,9 +2784,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	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
+			support 'n' processors. It could be larger than the
+			number of already plugged CPU during bootup, later in
+			runtime you can physically add extra cpu until it reaches
+			n. So during boot up some boot time memory for per-cpu
+			variables need be pre-allocated for later physical cpu
+			hot plugging.
 
 	nr_uarts=	[SERIAL] maximum number of UARTs to be registered.