Not all lawyers are the same :). Sure, not releasing the source code exposes you to less risks. I think the main thing that these Chinese companies fear is that

Not all lawyers are the same :). Sure, not releasing the source code exposes you to less risks. I think the main thing that these Chinese companies fear is that a competitor can produce similar products more easily if they have access to driver source code. From a legal standpoint, I imagine you would have less liability for bugs, because you opensourced it for anyone to see and have the option to improve upon. If the company did not introduce the bugs on purpose or as a result of some really negligent behaviour, the company doesn't have to fear liability issues. Potential patent claims etc. may be filed, but you can assess that risk. Let a patent research firm do a risk assessment and tell you how much chance people would have suing you. And all firms need to have some sort of legal liability insurance. If you can work it out with your insurance provider that you are going to opensource part of your code, you do not have to fear anything. You could always release two different drivers, one basic opensource driver for the community. One closed source optimized driver for the company. If you are using some risky IP etc. keep it in the closed source driver. AMD and Nvidia do this, seems to work for them.