Re: [Qemu-devel] E5-2620v2 - emulation stop error

Kevin O'Connor
2015-03-11T17:37:41Z

On Wed, Mar 11, 2015 at 04:52:03PM +0000, Dr. David Alan Gilbert wrote:
> * Kevin O'Connor (kevin@koconnor.net) wrote:
> > So, I couldn't get this to fail on my older AMD machine at all with
> > the default SeaBIOS code. But, when I change the code with the patch
> > below, it failed right away.
[...]
> > And the failed debug output looks like:
> >
> > SeaBIOS (version rel-1.8.0-7-gd23eba6-dirty-20150311_121819-morn.localdomain)
> > [...]
> > cmos_smp_count0=20
> > [...]
> > cmos_smp_count=1
> > cmos_smp_count2=1/20
> > Found 1 cpu(s) max supported 20 cpu(s)
> >
> > I'm going to check the assembly for a compiler error, but is it
> > possible QEMU is returning incorrect data in cmos index 0x5f?

I checked the SeaBIOS assembler and it looks sane. So, I think the
question is, why is QEMU sometimes returning a 0 instead of 127 from
cmos 0x5f.

> > David, any chance you can recompile seabios and double check your
> > output?
>
> Done;
>
> =========== Working ===========
> SeaBIOS (version rel-1.8.0-0-g4c59f5d-dirty-20150311_164408-dgilbert-t530)
[...]
> cmos_smp_count0=20
> cmos_smp_count=20
> cmos_smp_count2=20/20
> Found 20 cpu(s) max supported 20 cpu(s)
[...]
> =========== Broken ===========
> SeaBIOS (version rel-1.8.0-0-g4c59f5d-dirty-20150311_164408-dgilbert-t530)
[...]
> cmos_smp_count0=20
> cmos_smp_count=1
> cmos_smp_count2=1/20
> Found 1 cpu(s) max supported 20 cpu(s)

That's the same pattern I see.

-Kevin