Comment 6 for bug 568605

I'm using the word "crash" in the sense that a computer system that has ceased to operate correctly is said to have crashed, at least insofar as all the developers I am aware of have used it (including myself). In this case, my meaning should be quite clear: The graphics driver encounters a condition which it cannot rectify and ceases to correctly function with the violent consequence of having to reboot the system without saving any data. I suspect that if the GPU locked up, I would not even be able to see the dmesg output when I switch to the VT, because the GPU would be unable to execute further instructions to draw (and further, if that were the case, it would probably act like my system with the NVIDIA chipset, where the GPU locking up causes the kernel to subsequently lock up, making even the magic sysrq key fail to work, thus requiring a reset or power-cycle to get back up and running).

Software can and does crash without detecting that it crashed.

As an aside, things are so far so good running:

 Linux fennel 2.6.32-02063211-generic #02063211 SMP Mon Apr 12 12:03:56 UTC 2010 x86_64 GNU/Linux

From the mainline packages. I'll comment back in several hours if it hasn't yet crashed.

The only thing that I know is that there is no single activity that occurs before it crashes; sometimes, it will crash just sitting still, without having moved the mouse or switched windows or any of that. Compiz is running on this system (the only aspect that I have tailored of the UI is which fonts I use, not the effects or the extensiveness of them).