Problems with bhyve's kgdb support and loadable modules

[Kurt Lidl]

Is there any reasonable tutorial for using kgdb with the
bvmdebug kernel option?

A couple of folks I know have run into issues trying to
debug a FreeBSD stable/9 kernel from their bhyve
hosting machine (running stable/10).

In particular, the loadable modules that are in use in
the stable/9 kernel are being "troublesome" to get to
the point where source-level debugging actually works.

Even a pointer to a couple of "worked" examples might be
useful.

I've read this:
http://people.freebsd.org/~jhb/papers/bsdcan/2008/article/node4.html
but not all the techniques in there appear to work properly.

-Kurt