https://bugs.freedesktop.org/show_bug.cgi?id=89815
--- Comment #4 from Harald Judt h.judt@gmx.at --- (In reply to Michel Dänzer from comment #1)
Please attach /var/log/Xorg.0.log and the output of dmesg, preferably from after the problem occurred.
There is nothing strange in dmesg.
The image looks scrambled and is frozen, yet slightly reminiscent of the original screen.
What does "switching monitors" mean exactly?
this: xrandr --output DVI-1 --auto --primary --output HDMI-0 --off xrandr -s 1360x768
or: xrandr --output HDMI-0 --auto --primary --output DVI-1 --off
Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 16384 x 16384 HDMI-0 connected primary 1920x1200+0+0 (normal left inverted right x axis y axis) 550mm x 344mm 1920x1200 59.95*+ 1920x1080 60.00 59.94 59.93 1920x1080i 60.00 59.94 1600x1200 60.00 1680x1050 59.88 1280x1024 75.02 60.02 1440x900 59.90 1152x864 75.00 1280x720 60.00 59.94 1024x768 75.08 70.07 60.00 1440x480i 59.94 832x624 74.55 800x600 72.19 75.00 60.32 56.25 720x576 50.00 720x576i 50.00 720x480 60.00 59.94 720x480i 60.00 59.94 640x480 75.00 72.81 66.67 60.00 59.94 720x400 70.08 640x400 59.95 DisplayPort-0 disconnected (normal left inverted right x axis y axis) DisplayPort-1 disconnected (normal left inverted right x axis y axis) DVI-0 disconnected (normal left inverted right x axis y axis) DVI-1 connected (normal left inverted right x axis y axis) 1920x1200 60.00 + 1360x768 60.02 + 1280x1024 75.02 60.02 1280x768 59.87 1024x768 75.08 70.07 60.00 800x600 72.19 75.00 60.32 56.25 640x480 75.00 72.81 60.00 720x400 70.08
Also, a similar issue occurs even with glamour + dri3 (and maybe exa + dri2 etc., but I haven't tested this) for:
xrandr --fb 3840x1200 --output HDMI-0 --mode 1920x1200 --scale-from 3840x1200 --output DVI-1 --off
And the scaling does not work. It recognizes the fb change (the panel pager reflects this), but the scaling does not change. I've filed a bug for this some time ago, though things have changed a bit since then: https://bugs.freedesktop.org/show_bug.cgi?id=80678