Created attachment 43645 [details]
black screen of death
Watching a youtube video fullscreen with adobe flashplayer and then leaving fullscreen sometimes triggers a bug in the drm/radeon/ttm, this is with kernel 2.6.38-rc5, ddx from git and happens with both stock r600c from ubuntu 10.10 and r600g from git master.
The bug is only triggered sporadicly, but a good way to reproduce I found is to go and play a youtube video. e.g. http://www.youtube.com/watch?v=8ETDE0VGJY4 then position the mouse pointer at the bottom-right of the player where the fullscreen button is and start clicking many times as fast as you can. The player will go fullscreen and leave fullscreen a couple of times and will eventually trigger the bug.
I think this is a bug with pageflipping. Whereas I have successfully have been able to trigger this bug all the 3 times I tried with the method mentioned above with pageflipping enabled, so far I'm unable to reproduce this with pageflipping disabled.
Are you using a GL compositor like compiz or kwin in GL mode?
Nope. Just plain metacity without any form of compositing.
Does v3.0-rc3~42^2~8 (drm/radeon: fix oops in ttm reserve when pageflipping (v2), 2011-05-29) help?
Rafael Monica, Ubuntu 10.10 reached EOL on April 10, 2012. For more on this, please see https://wiki.ubuntu.com/Releases.
If this is reproducible with a supported release, it will help immensely if you filed a new report with Ubuntu by ensuring you have the package xdiagnose installed, and that you click the Yes button for attaching additional debugging information running the following from a terminal:
Also, please feel free to subscribe me to it.
For more on why this is helpful, please see https://wiki.ubuntu.com/ReportingBugs.