Comment 5 for bug 940771

I suspect this is a duplicate of bug 938770, and I'm beginning to suspect it's related to touchpad/gesture support. I don't really think it's related to i915, and I'm skeptical that it's even a kernel problem. I was able to reproduce exactly the hang I've been seeing using your file.

To confirm this is a duplicate, can you answer the following questions?

1. Can you describe exactly what you see when this happens? What I see is a completely unresponsive desktop -- the mouse pointer moves, but nothing responds to clicks or keyboard input.

2. If your behavior is as I describe it, is the machine generally alive other than the desktop being responsive? Can you switch to a virtual terminal (i.e. press Ctrl+Alt+F1), log in, and run 'sudo service lightdm restart' to return to a functional desktop?

3. How are you scrolling when this happens? E.g., using a mouse or a touchpad, using a scroll wheel or touchpad gestures (two-finger or edge scrolling) or the scroll bar.