I disabled the check in mountd for EPERM, and suddenly I can boot far enough
to get a no such file or directory for /usr/libexec/getty.

It appears that mountd semi-randomly fails to be able to export various
paths; most visibly, it looks like the loop on trying to mount the
filesystem on which something is found is biting me, because I have a swap
space and two directories which are on the same filesystem, but which have
to be exported separately, since -alldirs doesn't seem to work.

*sigh*.

-s