Ubuntu
xserver-xorg-video-intel package

  1. Bug #377090 (dri2-swapbuffers)
  2. Comment #23

Comment 23 for bug 377090

Revision history for this message
In , Łukasz Kuryło (lukasz-kurylo) wrote :

I've found out what causes the problem. As I said before I have 2 monitors and I use them in extended desktop configuration:
xrandr --output VGA --right-of LVDS --auto.

The problem is that my LVDS is 1680x1050 and VGA is 1920x1200. So what I get after xrandr is virtual screen 3600x1200.

______________________
| | |
| S1 | S2 |
| | |
|_________| |
|XXXXXXXXX|___________|

if I instead did:

xrandr --output VGA --right-of LVDS --mode 1680x1050
_____________________
| | |
| S1 | S2 |
| | |
|_________|_________|

everything works fine.

So I believe the problem is when driver has to redraw area that is bigger then physical screen. Maybe then there is no MI_WAIT_FOR_PIPEB_SCAN_LINE_WINDOW for
region which includes XXXXXXXX part (is partially below the screen).