Comment 51 for bug 1866870

I've tested smoe more cmbinations and found that I van have v4.2 work on focal.
Eventually I have realized that when I install start the qemu from Ubuntu not only that but also the formerly working build of v4.2.0 from git start to fail (without rebuilding).

A bit of package bisect later I found seabios to be related.
Focal is at 1.13.0-1
Eoan is at 1.12.0-1

After I knew that I verified and found it really only triggers on seabios 1.13.0.

With 1.13 I was also able to break the qemu v4.0.0 git build on eoan.
As well as the packaged qemu in Eoan.

So it seems we are actually looking for a problem of seabios (instead of qemu) with the Penryn chip.

I'll look at their changelog and bisect that tomorrow as time permits