I have a bag which is less than the max on height and width but 3cm over in depth. In linear terms I am under the total but my airline are not clear if they are quoting in a linear way.
It's Emirates and it's about carry-on bags; they specify 55cm * 38cm * 20cm. My bag is 54 * 35 * 23. It's a soft bag and not packed full. Route is Toronto to Dubai. I did see on their website reference to a rolling bag which if under the linear measurements could go as cabin bag, but that was the only reference to cabin luggage in a linear context