[Qantourisc]

Governments just need to regulate one thing on the ECU: access to the code. They don't have to make any specific laws. Of course to be able to proof, this is the code uses, one would need access to upload it to the ECU. (And compile it.)

Which gives another issues: people breaking the law by changing their ECU map, to exhaust more pollutants.

But I suppose this is no more of an issue then it was/is with WiFi access points, not a lot of people do it, and you don't want to brick your car :D