I also have this problem, except only the brightness up key causes it. The brightness down key does not cause a problem, indeed it actually lowers the brightness of the screen.
I have tried the 3.8.5 and 3.5.0 kernels. The crash can be triggered at any time after booting the kernel, but the brightness up key works fine in the bios. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/992720 Title: [Lenovo E420s] Hitting brightness keys causes machine to lock up To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/992720/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs