I tried doing Alt+SysRq+T again and now it printed a few screenfuls of text. I was able to read that usplash was running before the screen was filled with a call trace. I couldn't find any log of this in /var/log, but I'll take a couple of pictures of the output tomorrow when I have a camera available.
The latest usplash didn't solve this for me, but disabling usplash did. -- BUG: soft lockup detected on CPU#0! https://launchpad.net/bugs/60053 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
