In yesterdays qualification session the clean question also played a large role in general. There are quite a few places on track where there is a lot of space between the white line and tarmac end. Places that come to mind are after the first hairpin (white line or kerbs), in the first tunnel, above mentioned final tunnel, and the white line on the start finish leading to T1.
The rules in the OP state kerbs are track limiters, so I would assume the rock patch in the final tunnel is off limits, there are kerbs at the tarmac edge. The white line is tricky at times thought.