Christopher SEKIYA wrote:

> On Tue, Dec 14, 2004 at 10:33:22AM +0100, Florian Stoehr wrote:
> 
> > ...as encountered by someone elso on r5k and me on my Indigo2 ?
> 
> Not completely.  The commit to which you refer is the uncontroversial part
> of the fix.
> 
> Attached is the controversial part.  The pmap hack is not correct, but it
> fixed the panic on my r5ksc (revision 2.0).

So on the R5000, the L2 cache doesn't help with alias detection?  Is
this problem specific to the way the caches are wired up on this model
SGI, or a problem with the R5000 in general?

If I read your suggested patch correctly, it will cause extra unneeded
cache flushes on other CPUs/machines with multi-way data caches that
have also have an L2 cache.  Do we know of any that exist, ignoring say
the Broadcom/Sibyte CPUs where the L2 is effectively invisible to us?

> This does not address the system coma issue; that is due to a CPU bug (pre-2.0),
> and I'm unsure how to fix it right now.

What is the "system coma issue"?  I've seen a handful of passing references
to it now...

Cheers,
Simon.
--
Simon Burge                            <simonb@wasabisystems.com>
NetBSD Support and Service:         http://www.wasabisystems.com/