Max, please see
http://forums.ulyssesmod.net/index.php/topic,5807.msg26870.htmlFrom our understanding, Gmod broke linux binaries for some lua addons after one of his many Gmod13 updates.
Gmod is pretty unstable on Windows right now, let alone linux.
We hope once Garry gets it stable on Windows, he'll start working on linux stability.
Until that time, I'm reasonably sure there is little we can do.
If you can provide any server console log perhaps, up to the segmentation fault, it
might help us look.
If it's not even getting that far, then, don't know what else to do.
Perhaps even try what it says after the crash (re: -debug).
No idea if we'd be able to tell, but perhaps you could find how to report whatever crash is occuring to Garry after searching Google to see if it's already known
EDIT - I've also renamed your topic to include Linux.