On occasion, I get a 'piixide: missing untimeout' error when I try
to wake up my laptop after suspending it.  At such times, there's
nothing I can do but lean on the power switch -- the disk is frozen,
so can't get to anything.  This brings up several questions:

a) Why does this happen?  My guess is a race condition, where I happen
to suspend at just the wrong time relative to disk I/O.

b) Is there a better way I can recover? 

c) Is there a better thing the code could do?  Should it panic at
that point, or are there benign instances of a missing untimeout?