When I turn on KDE compositing the desktop freezes more often than not. These
freezes can also be provoked when configuring mplayer for GL output and opening
a video file. If that alone is not enough, just change repeatedly from window
to fullscreen and back. Attaching Xorg.0.log and dmesg of such a crash.

I can reboot the system cleanly using alt+sysrq+r and ctrl+alt+del but any
attempts to get a nice backtrace of the X server with gdb failed due to the
process hanging in kernel space.

Hardware:
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI]
Curacao XT [Radeon R9 270X]

Running:
kernel 3.14,
libdrm2-2.4.99~git20140411-1.1,
xorg-x11-server-7.6_1.15.99.902-306.1
Mesa-10.2~git20140411-5.1
llvm-r600-3.5~svn20140408-1.1.x86_64
openSUSE 13.1

Downgrading components to openSUSE 13.1 stock versions did not help except for
downgrading the kernel to 3.11.