Discovery and attorney fees would be a big portion of the picture here. If there's no settlement reached, each party will have a right to collect and comb through documents related to the lawsuit. Further, they'd have the right to interview (take a deposition of) everyone involved in decisions surrounding the controversy.
That means, nVidia would (likely) have the right to start talking to people in HP, Intel, AMD, Oracle, broadcom, On semiconductor, etc. Practically anyone involved with kernel development and decision making around kernel development.
The US civil legal system is designed to try and force parties into settlement. However, when you have a major corporation with cash to burn, they can win simply by dragging everything out.
The suit in this case would be for compliance with the GPL.