https://bugs.freedesktop.org/show_bug.cgi?id=81644
--- Comment #29 from jackdachef@gmail.com --- using the new firmware (http://people.freedesktop.org/~agd5f/radeon_ucode/ucode.tar.gz) didn't seem to make a change in stability:
starting in fluxbox + firefox + gnote
watching videos on youtube (adobe flash player) for several minutes, writing some notes in gnote, exiting; gmail, google+
starting in Xfce4+ compiz-fusion, exiting
starting in fluxbox + firefox + gnote
browsing, watching wallpapers, gmail, google+
text corruption, especially in gmail & google search results occured with:
radeon 0000:01:00.0: Packet0 not allowed!
couldn't pinpoint what triggered it, several occurences in dmesg
starting up chromium, browsing youtube (adobe flash explicitly disabled), wanted to watch a video (HTML5 video), screen doesn't react anymore, turns black
gpu/screen turns black, hardlock
will attach dmesg later, no suspicious content besides
radeon 0000:01:00.0: Packet0 not allowed!
any useful data in connection with chromium -> hardlock, all data lost