FYI 3.11 kernel landed in Ubuntu 13.10 development version, so this is now also fixed there without any tricks.
Ubuntu 13.04 is apparently getting a partial fix (not sure if it's enough, two patches were originally mentioned as being relevant) in its next kernel update (bug #1204666), and I've attached a patch to bug #971809 that would bring the other part there too if picked up by kernel stable release update team.
FYI 3.11 kernel landed in Ubuntu 13.10 development version, so this is now also fixed there without any tricks.
Ubuntu 13.04 is apparently getting a partial fix (not sure if it's enough, two patches were originally mentioned as being relevant) in its next kernel update (bug #1204666), and I've attached a patch to bug #971809 that would bring the other part there too if picked up by kernel stable release update team.