[OpenIndiana-discuss] Boot hangs after configuring devices (last notice is of pseudo devices

[Richard Lowe]

A good thing to do is to get into mdb when it's hung, and see where we
are with the ::stacks command.
https://illumos.org/books/dev/debugging.html has other tips.

I would add if you set the 1 bit of `moddebug` when you're in kmdb (I
think moddebug/W 80000001 is verbose and stop on _init, but I tend to
forget), we will stop whenever a module `_init` is called, which can
be a good trick to try to narrow down where things might have gone
wrong if we don't respond to any means to get into kmdb.

More manually, an illumos version which works and one which doesn't
work will narrow down which illumos changes might have caused
problems.