I am running Ubuntu Maverick on amd64 with the 2.6.37-020637rc3-generic mainline kernel, and Mesa packages with version string 7.10.0~git20101123+gallium.ed8b5fb2-0ubuntu0tormod from the xorg-edgers/radeon PPA. My video card is an ATI FireGL 8800.
In running Wings3D, I no longer encounter GPU lockups as reported in bug 31417. Instead, the application's 3D viewport area blanks out completely (all white) for varying lengths of time, depending on what is going on:
* If I'm just moving the pointer around, the viewport might "flicker" briefly from time to time;
* If I right-click to bring up a context menu, the viewport usually flickers on cue;
* If I click to rotate the camera view, the viewport blanks and stays blank, and only in brief, intermittent flashes do I see the view/object being manipulated. The blanking appears to coincide with what would normally be a smooth panning motion, and the un-blanking with any pause in that motion.
This is the first instance of this behavior that I've encountered, and it was not observed in the 20101103 git pull (albeit with a different desktop configuration), so this may well represent a regression.
(At the same time, I should point out that I am no longer able to reproduce the GPU lockup described in bug 31417, so at least something's going right somewhere.)
For some reason, the blanking does not occur when I run Wings3D in the standard Ubuntu desktop (GNOME + Compiz). I normally use Xfce/Xubuntu, and the bug occurs there, and it also occurs in a minimal X session with twm.
Further testing has shown this to be an application bug. On the same system, Wings3D 1.2 displays correctly, whereas Wings3D git master (which I normally use) has the flickering/blanking behavior.