Re: [Xen-devel] [PATCH][QEMU] Clear bios framebuffer with minimal writes

[Gary Grebus <ggrebus@xxxxxxxxxxxxxxx>]

On Thu, 2007-10-25 at 13:14 -0400, Gary Grebus wrote:
> On Thu, 2007-10-25 at 16:34 +0100, Keir Fraser wrote:
> 
> > Ugh, that is awkward. Did you do this hack before the stdvga
> > emulation-in-xen and buffered-io patch that you guys also sent out today? I
> > wonder whether that speeds up vga writes enough, or whether you needed this
> > hack despite the speedups that other patch achieved? Overall, I guess I'm
> > not against this patch even though it is a bit sleazy. :-) But obviously
> > it's even better if the problem goes away by other means...
> > 
> 
> This patch predates the stdvga emulation-in-xen and buffered-io changes.
> I'll try with only the later changes and see if they are sufficient.
> 

I tried with only the stdvga and buffered-io patch.  Things got worse,
to the point that Vista no longer boots, encountering a BSOD due to a
timeout in Vista graphics driver.

Apparently the stdvga and buffered-io patch de-optimizes this particular
case, but we didn't notice due to the vgabios patch.

The vgabios patch fixes the intermittent "BSOD on screen resize" problem
either way.  We won't know if it's really necessary until we can fix the
stdvga etc. patch which at the moment looks a little suspect.

        /gary




_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel