K 10
svn:author
V 3
kib
K 8
svn:date
V 27
2015-05-27T09:22:50.108816Z
K 7
svn:log
V 495
Right now, dounmount() is called with unreferenced mount point.
Nothing stops a parallel unmount to suceed before the given call to
dounmount() checks and locks the covered vnode.  Prevent dounmount()
from acting on the freed (although type-stable) memory by changing the
interface to require the mount point to be referenced.  dounmount()
consumes the reference on return, regardless of the sucessfull or
erronous result.

Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks

END