Created attachment 264390 [details]
glitched control center

I've been testing gnome with the open source radeon drivers off and on for a few months now, and have consistently noticed some graphical glitches. The easiest way to reproduce the glitches is using gnome-control-center. Simply open the control center, enter one of the categories, and then go back. The top and left sides of the window will appear as though an extra copy of the window has been composited over them. Going to the "Displays" settings also triggers a (slightly different looking) glitch on its own. Changing focus to another window fixes the glitch (likely due to the corrupted regions needing a repaint).

I believe this behavior is in mutter, as some of the glitches appear on the window's drop shadow, not just the header bar. Also, I recall seeing this glitch prior to the control center having a header bar, although I don't know of a reliable way to trigger it in an application that still uses server-side decorations.

I should note, however, that I do not actually believe this is a bug in gnome-shell. I normally use Intel integrated graphics, and have not seen this glitch while doing so. This is exclusive to Radeon use, and perhaps specifically to the radeonsi driver (I cannot verify on any others, as I only have one card). However, I thought it'd be useful to have a bug here to possibly spur communication.

I'm using:
    Arch linux
    kernel 3.12.5
    mutter 3.10 (other relevant gnome components are likely to be 3.10 as well)
    ati-dri from git, 2013-12-16
    llvm from svn, 2013-12-16
    xf86-video-ati 7.2.0

Attached are some screenshots of the glitch.

I'll also open a ticket at the freedesktop bugzilla, as I think that is where the bug is likely to actually be.