This lockup happened after I'd turned my back long enough for a screensaver to kick in. I am using the latest xorg-x11-drv-ati from -git, along with Xorg 1.9.5, so page-flipping is also enabled. Mesa is r300g from Mar 25th 2011. According to the serial console, the kernel continued to spit out "Failed to schedule IB" errors until finally it froze completely.
Created attachment 52462 [details] dmesg output, showing GPU lockup
Created attachment 52472 [details] Xorg log file from crash
Created attachment 52482 [details] .config file for kernel The hardware is a dual P4 Xeon (hyperthreading also enabled) with 2 GB of RAM. So I'm not sure why the stacktrace contains "init_transmeta()".
It has been suggested that this bug is actually a symptom of this Xorg bug: https://bugs.freedesktop.org/show_bug.cgi?id=35452
Created attachment 66992 [details] dmesg output, showing GPU lockup Looks like the bug is still present in 2.6.39.3. Again, turning my back long enough for an OpenGL screensaver to kick in was all it took.
Is this still an issue with a newer kernel?
Hard to be sure, mainly because Gnome 3 doesn't seem to run my OpenGL screensavers for very long before putting the monitor into DPMS sleep instead. I did recently (i.e. 3.5.3 kernel) have screensaver trouble with my laptop and its M66GL chip: X had difficulty waking up after entering DPMS sleep, and the kernel crashed with memory errors shortly afterwards anyway. But this could be a separate bug.