> If it was GPLv2 alone, proprietary modules would probably be infringing I'm not so sure, at least in the US. There were several cases in the '80s and 90s or

> If it was GPLv2 alone, proprietary modules would probably be infringing I'm not so sure, at least in the US. There were several cases in the '80s and 90s or thereabouts involving video game cartridges which might be relevant. The consoles back then did not have memory protection or multiple address spaces or user/system modes. The ROM in the cartridge simple appeared at a fixed place in the address space, and typically the firmware in the console would do some system initializing, then call an entry point in the cartridge. The code in the cartridge had full access to the hardware and to the firmware in the console. The console manufacturers wanted to control the cartridge market. Among the many ways they tried to keep third parties from making compatible cartridges was copyright. The firmware in the console was copyrighted by the console manufacturer, and the code in the cartridge (in most cases [1]) extensively called into that firmware. Since the third parties had figured out the firmware by reverse engineering (usually in violation of the console's license) in many cases they even called into firmware code that authorized games did not use because that was not part of the firmware's API. My recollection is that the third parties won in most of those cases. [1] I believe that there were some third party games where the game maker had not been able to figure out how the firmware worked but they did know how the hardware worked, and so they made their cartridges completely take over. The console firmware was effectively just a boot loader for them.