corrupted picture on the display. Also I see the following lines in logs: Dec 22 22:05:34 note kernel: [44316.540242] compiz.real[6401]: segfault at 48 ip 08055c8c sp bfd492b0 error 4 in compiz.real[8048000+34000] Dec 22 22:05:53 note kernel: [44332.984062] metacity[6340]: segfault at 0 ip 080abab3 sp bfdeb8b0 error 4 in metacity[8048000+7a000] I looked into compiz code and found that segmentation fault happens in src/display.c in the doPoll() function. Strict place is when w w->next is executed in the cycle. Also I found that WatchFds used in doPoll() can be added and removed through compAddWatchFd() and compRemoveWatchFd() calls. Last functions are called from different plugins. I suppose that possible issue cause is lack of synchronization between threads that use these functions. Should the WatchFd usages be synchronized? I use Ubuntu 8.10 and compiz 0.7.8 from Ubuntu repository. Thanks, Vitaly