Sounds like something happened, the aircraft systems noted it, but it never was determined (by those systems) to be serious enough to post a message requiring crew action. And since the flight completed uneventfully, its hard to argue with that determination.
Messages indicated a problem with the right Rolls-Royce Trent 800 engine, and included a thrust asymmetry compensation message that is issued when the flight control computer automatically uses rudder input counter the yaw effects of a failed engine.
What does the QRH procedure say?