XServer sometimes hangs (100% CPU) when closing a window on R500/video-ati

[Alexander Hunziker]

I've been using compiz on an ATI Mobility Radeon X1400 for a few days now. Using the default driver (video-ati). Sometimes, when trying to close a window, it just hardlocks and won't accept any input anymore (can't switch to terminal, can't kill XServer), though the mouse pointer can still be moved. The only thing that can be done is a cold reboot.

[Alexander Hunziker (alex-hunziker)]

I've been using Compiz on R500 on a daily basis now for a few weeks, always using the most recent radeon driver form Tormod Volden's PPA. So far, I have not experienced the described crashes anymore with those more recent drivers.

[Alexander Hunziker (alex-hunziker)]

The bug persists. I cannot be sure it has anything to do with Compiz, that was my first guess because it always happens when i close a program. Today though, it happened when I closed a program from the tray icon while the program was minimized to tray - there was no visible window being closed.

It's tough to debug, because it only happens once every week or so, but reproducibly when i close an app. Again, I have no possibility to control the machine locally. The fan speeds up, so I think the CPU is working.

Can anybody give me advice how to debug when it happens next time? I have installed an SSH server now in the hope to login remotely next time it happens.

[Alexander Hunziker (alex-hunziker)]

It happened again just now. This time, I logged in remotely and saw that the process "Xorg" was using 100% CPU. I was able to kill it over SSH, after which the X session is shut down and I'm again presented with the login screen.

Can somebody please give me instructions what to do next time it happens in order to debug this? At a rate of once every two weeks, I need to be prepared, or else we'll never get this fixed :-)

[Dimitrios Symeonidis (azimout)]

alexander, thank you for your persistence
i'm no expert here, but you might want to take a look here:
https://wiki.ubuntu.com/X/Debugging
especially:
https://wiki.ubuntu.com/X/Reporting
good luck

[Alexander Hunziker (alex-hunziker)]

Attaching Xorg.0.log.old. It contains a lot of messages like:

[mi] EQ overflowing. The server is probably stuck in an infinite loop.
[mi] mieqEnequeue: out-of-order valuator event; dropping.

[Alexander Hunziker (alex-hunziker)]

Also, my xorg.conf. I'm using:

* The radeon driver 6.10 released very recently. It also happens though with the version released with Intrepid.
* EXA
* Compiz

[Alexander Hunziker (alex-hunziker)]

It happened again, and i was *so* prepared :-) Here's a backtrace, hope that helps.

[Janigo (cardi-gmx)]

I can confirm this on openSUSE 11.1 (gnome) on a thinkpad T60 with an radeon X1400 graphics-card. It only happens if compiz is running. Using radeonHD driver, compiz does not work (white screen).

[Jonathan Thomas (echidnaman)]

Should be fixed in Jaunty.