Merge branch 'next'

diff --cc qa/workunits/rbd/map-snapshot-io.sh
index 882bf5d2dbc4547edc36acff0834c99ef288b132,b53a81387d4fc9932c37e751f434c9e2a92c1c09..c16030e2d8e8073f79d40af1d4e86ba941b9aa86
--- 1/qa/workunits/rbd/map-snapshot-io.sh
--- 2/qa/workunits/rbd/map-snapshot-io.sh
+++ b/qa/workunits/rbd/map-snapshot-io.sh
@@@ -15,8 -15,14 +15,15 @@@ rbd snap create image@s
  dd if=/dev/zero of=/dev/rbd/rbd/image oflag=direct count=10   # used to fail
  rbd snap rm image@s1
  dd if=/dev/zero of=/dev/rbd/rbd/image oflag=direct count=10
+ 
+ udevadm settle  # udev is does blkid on device close; yeesh!  see #4183
+ 
  rbd unmap /dev/rbd/rbd/image
 +rbd rm image
  
+ # wait a few seconds for the async kernel bits to clean themselves up
+ sleep 4
+ rbd rm image || :
+ 
  echo OK