Unity hangs when touching my touchpad/trackpad

Bug Description

Happens quite few times a day

I cannot reproduce this crash.

Versions used:
compiz 1:0.9.7.0~bzr2995-0ubuntu5
unity from lp:unity revision 2040
nux from lp:nux revision 586

I get this every time I touch my trackpad. It is a hang, not a crash. The GDB backtrace attached to this bug also shows a hang, not a crash.

When this same hang was analyzed in January of 2011 the Unity developers said there was an XSync call missing from the query sequence, if that information is any help.

Andrea,

Can you confirm that this is a hang and not a crash?

Chase, it could be a hang, unity just freezes and I need to go to a tty and re-run it.

Andrea,

Could you please try unity from lp:~dandrader/unity/lp942625 and tell us if the hang still occurs? And also whether you get the warnings "GestureEngine - XQueryTree failed!" and/or "GestureEngine: data->window == 0"?

Awesome! I have been able to reproduce this very problem when running the trunk versions of compiz&friends. Now I can check if my patch works myself. :)

Ok, the bug stopped appearing on my machine. I didn't have the change to try out my patch. Thus Andrea, I still need your help.

At least I can confirm it is a hang and not a crash.

Was able to reproduce it again and found the cause. Fix has been proposed.

I'm happy to help test this as well. I'm seeing this very often on my MacBook Pro.

This bug was fixed in the package unity - 5.6.0-0ubuntu1

---------------
unity (5.6.0-0ubuntu1) precise; urgency=low

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