Re: [Bugme-new] [Bug 9990] New: tg3: eth0: The system may be re-ordering memory-mapped I/O cycles

[Andy Gospodarek <andy@greyhouse.net>]

On Thu, Feb 14, 2008 at 02:48:09PM -0800, Michael Chan wrote:
> On Thu, 2008-02-14 at 17:12 -0500, Andy Gospodarek wrote:
> > On Thu, Feb 14, 2008 at 01:25:27PM -0800, Michael Chan wrote:
> > > On Thu, 2008-02-14 at 13:56 -0500, Andy Gospodarek wrote:
> > > > That should be a simple matter of adding the right pci-ids to
> > > > tg3_get_invariants -- hopefully Ralf will respond and we can get that
> > > > knocked out quickly.
> > > > 
> > > > 
> > > 
> > > It doesn't look like it was re-ordered IO.  If it was, it should have
> > > self-recovered without hitting the BUG().
> > > 
> > 
> > Good catch, Michael!  I missed that it paniced since I expect to see
> > some sort of backtrace when that happens.  We should try and get that
> > bridge added to the list though, to avoid repeated complaints that there
> > is a tg3 bug.
> > 
> > 
> 
> Andy, I think you still missed my point.  I don't believe this problem
> was caused by the bridge or the chipset at all.  Some corruption caused
> us to not find the SKB in the TX ring where it was expected.  So the
> driver assumed it was the bridge re-ordering I/O and printed that
> warning message and took recovery action.  The recovery action had no
> effect in this case since apparently it was caused by something else and
> the corruption happened again later.  This 2nd time, we hit the BUG_ON()
> seeing that the recovery action did not work.
> 
> 

Ah, I see.  Due to at leat a 2 second delay between the message and the
panic, I figured it would be good data to gather....