A point that AnFi and others are missing is that the swash plate is continually changing the pitch angle during the orbit.
Sure, the retreating blade is at its max pitch at the 9 o'clock position, and the blade is at its greatest rate of flapping up as well, but from then on the swash plate is driving its pitch angle downwards - but the disc still reaches its highest point in the orbit at the 6 o'clock position due to its inertia.
So, even if a segment of the blade reaches a stall condition, it will rapidly come back out of it due to the combined effect of the decreasing pitch angle, the fact that the blade is still on its way UP (not flapping down), and the changing direction of the airflow going from behind the blade at 9 to along the blade at 6.
People get stuck on the idea of flapping to equality with the disc high at the front and low at the back, but to fly forwards, the swash plate has feathered the blades and it is flapping down to the front and up to the back. Equality of lift is forced by the swash plate.