Most likely nothing.

But just a warning of what can happen if your engine was considerably overfilled. The oil would have to find it's way out somehow and most likely it would breathe heavily and the exhaust would be smoky. In an extreme case the oil could come up past the piston rings causing the engine to hydraulic lock.

It's always better to be slightly under tha maximum mark than over. It's much easier to top up than to drain out.....