K 10
svn:author
V 3
kib
K 8
svn:date
V 27
2012-12-24T13:29:22.025030Z
K 7
svn:log
V 415
MFC r242476:
The r241025 fixed the case when a binary, executed from nullfs mount,
was still possible to open for write from the lower filesystem.  There
is a symmetric situation where the binary could already has file
descriptors opened for write, but it can be executed from the nullfs
overlay.

Handle the issue by passing one v_writecount reference to the lower
vnode if nullfs vnode has non-zero v_writecount.

END