[virglrenderer-devel] Anyone see black screen when refreshing qemu window?

[Lepton Wu]

On Tue, Jul 24, 2018 at 12:14 PM Lepton Wu <lepton at chromium.org> wrote:
>
> On Tue, Jul 24, 2018 at 12:10 PM Gert Wollny <gert.wollny at collabora.com> wrote:
> >
> > Am Dienstag, den 24.07.2018, 11:48 -0700 schrieb Lepton Wu:
> > > Hi,
> > >
> > > Here is a bug I met when running virlgl + qemu with my guest (Chrome
> > > OS). I've put a video here to show what I mean: https://youtu.be/yG-
> > > BbWHOwG4
> > >
> > > As you can see, when I moved around another application window, qemu
> > > will show black screen sometimes.
> > I haven't seen it like this, but when I run virgl with the SDL backend
> > (which is required to get a GLES host context on the desktop linux)
> > resizing or moving to another virtual screen and back will result in a
> > black window with a simple X window manager (like backbox). I noticed
> > that with the gnome desktop inside the guest this didn't happen.
> > I think there is a problem with when the desktop is redrawn, it isnot
> > always signalled. I even have a little script to force a redraw that I
> > can run from an ssh console.
> >
> > export DISPLAY=:0
> > xrandr --output Virtual-1 --off
> > xrandr --output Virtual-1 --auto
> >
> > Actually, I just noticed that when I turn off the compositing on my
> > desktop then it is worse. Movong the window or overlapping anather
> > window results in all black, and only with these commands above I can
> > bring it back.
> >
> > > This only happen when  running qemu with virgl option.
> > > Actually this could be a bug in qemu side, but just wondering, is
> > > this a known issue happening to everybody or just something
> > > specific to my setup.
> > I think it must be a SDL/qemu problem that it doesn't send the refresh
> > command properly.
> Thanks, yeah, I am running SDL. OK. Will put some time to see if I can
> find out something.
To close the loop, this is the patch for fixing this:
https://lists.gnu.org/archive/html/qemu-devel/2018-07/msg05230.html
> >
> > Best,
> > Gert
> >
> >
> >
> > >
> > > Thanks!
> > > _______________________________________________
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> > > virglrenderer-devel at lists.freedesktop.org
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