Any way to debug a hard lockup?

[Michael C. Shultz]

On Wednesday 07 July 2004 12:03, Conrad J. Sabatier wrote:
> For the last few days, my amd64 box (Athlon 64 3200+, 5.2-CURRENT,
> updating just about daily lately) has been locking up hard fairly
> often, and I have no clue as to why.
>
> Checking the logs after rebooting reveals nothing at all out of the
> ordinary.  The box just "seizes up" and that's that.  Only thing to do
> is a power-down and restart.
>
> Changing from SCHED_ULE to SCHED_4BSD appears to make no difference at
> all.
>
> My other box, an older (32-bit) Athlon, has been rock stable.  I've
> been keeping both machines updated simultaneously to exactly the same
> revisions, using as near-identical system settings as possible also,
> the main difference being I'm running X.org/GNOME on the amd64 box and
> no X on the i386 box.
>
> Any suggestions?  Instinct tells me it may be a problem with some of
> the ports I'm running (X.org/GNOME, hence the Cc:s), but how to verify?
> Sure, I could run without X a while and see how it goes, but that still
> won't help to isolate the problem, if it is, in fact, port-related.
>
> Thanks.

I had a lock up a few days ago, the first time in ages that has happened.
I had just done a complete buildworld the day before.  The lockup occured
while I was cvsupping.  Only, after rebooting and trying again everything
worked fine and I have had no problems since. Note: I run 4.10 stable and
I was running kde when the lockup occured. Both Gnome and KDE seem to be
working fine afterwards.

-Mike