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

Pull documentation update from Jon Corbet:
 "There is a nice new document from Neil on how pathname lookups work
  and some new CAN driver documentation.  Beyond that, we have
  kernel-doc fixes, a bit more work to support reproducible builds, and
  the usual collection of small fixes"

* tag 'docs-for-linus' of git://git.lwn.net/linux: (34 commits)
  Documentation: add new description of path-name lookup.
  Documentation/vm/slub.txt: document slabinfo-gnuplot.sh
  Doc: ABI/stable: Fix typo in ABI/stable
  doc: Clarify that nmi_watchdog param is for hardlockups
  Typo correction for description in gpio document.
  DocBook: Fix kernel-doc to be case-insensitive for private:
  kernel-docs.txt: update kernelnewbies reference
  Doc:kvm: Fix typo in Doc/virtual/kvm
  Documentation/Changes: Add bc in "Current Minimal Requirements" section
  Documentation/email-clients.txt: remove trailing whitespace
  DocBook: Use a fixed encoding for output
  MAINTAINERS: The docs tree has moved
  Docs/kernel-parameters: Add earlycon devicetree usage
  SubmittingPatches: make Subject examples match the de facto standard
  Documentation: gpio: mention that <function>-gpio has been deprecated
  Documentation: cgroups: just fix a few typos
  Documentation: Update kselftest.txt
  Documentation: DMA API: Be more explicit that nents is always the same
  Documentation: Update the default value of crashkernel low
  zram: update documentation
  ...

1 files changed, 5 insertions, 0 deletions

diff --git a/Documentation/DMA-API-HOWTO.txt b/Documentation/DMA-API-HOWTO.txt
index 55b70b903ead..d69b3fc64e14 100644
--- a/Documentation/DMA-API-HOWTO.txt
+++ b/Documentation/DMA-API-HOWTO.txt
@@ -681,6 +681,11 @@ or:
 
 as appropriate.
 
+PLEASE NOTE:  The 'nents' argument to dma_sync_sg_for_cpu() and
+	      dma_sync_sg_for_device() must be the same passed to
+	      dma_map_sg(). It is _NOT_ the count returned by
+	      dma_map_sg().
+
 After the last DMA transfer call one of the DMA unmap routines
 dma_unmap_{single,sg}(). If you don't touch the data from the first
 dma_map_*() call till dma_unmap_*(), then you don't have to call the