Can you please create an /etc/X11/xorg.conf with these contents and see if it works around the problem?
Section "Device" Identifier "Default Device" Driver "radeon" Option "EnablePageFlip" "False" EndSection
Can you please create an /etc/X11/xorg.conf with these contents and see if it works around the problem?
Section "Device"
Identifier "Default Device"
Driver "radeon"
Option "EnablePageFlip" "False"
EndSection