If the lost+found directory is created by fsck, it will do a cacheino()
which sets the inoinfo's i_parent and i_dotdot to 0, but they never get
set to ROOTINO. This means that propagate will never find lost+found and
its descendents, subdirectories will remain DSTATE (instead of DFOUND)
even though they *are* correctly linked in, and pass4.c will try to
clear them unsuccessfully, thinking that there is no link count from the
DSTATE directory's parent. The result is that you need to run fsck twice
and get link count increasing errors (which are unexpected and fatal
when running in preen mode). The fix is to set i_parent and i_dotdot to
"parent" after the second cacheino() call in dir.c:allocdir().
Obtained from: "Ethan Solomita" <ethan@geocast.com> (of the NetBSD Project)