Sat, Nov 06, 2004 at 05:12:58PM +1100, matthew green:
>    if the processor were stuck in a trap handler, say data miss (fill, spill,
>    ...), that'd be at a higher priority than a interrupt like hard/soft clock,
>    so it'd never be serviced.  right?
> 
> 
> yeah. but then all/most other processing would stop as well?
> i'm still quite fine with most of my interactive shells and
> NFS is working fine still....

hrm, I misunderstood.  so, it is only the "selected process" that "sleeps
forever".

I thought that some folks had reported that their only recovery path
was power-cycling, meaning that the machine had become totally
unresponsive.  so, I must be muddling 2 problems.

I guess there are 3 mortally wounding problems.  sleeps forever, pmap seg 0
(PR 24126), and this hanging.

I had a heck of time with a full build yesterday, took most of the day.
my ac200 hung hard ~4 times.  each time it appears to have been in
ufast_dmmu_miss.