The Trusty kernel now has the 3.13.11.6 upstream updates. However, as suggested by dualshock3nerd in comment #59, the bug may never have been introduced in mainline, only trusty.
It would be great if you could apply the latest trusty updates, to get the 3.13.11.6 updates and see if this bug still exists. If it does, we can investigate further.
The Trusty kernel now has the 3.13.11.6 upstream updates. However, as suggested by dualshock3nerd in comment #59, the bug may never have been introduced in mainline, only trusty.
It would be great if you could apply the latest trusty updates, to get the 3.13.11.6 updates and see if this bug still exists. If it does, we can investigate further.