Thank you for your reply. Unfortunately, I don't have a very clear understanding (probably nobody does). As far as I understand, when "running two programs in

Thank you for your reply. Unfortunately, I don't have a very clear understanding (probably nobody does). As far as I understand, when "running two programs in the same address space" (this is, LKMs), it's fine to have non-GPL compatible modules as long as these don't interact with GPL DRMed symbols. You can have self-contained stuff and that won't be an issue. You could also no licensing limitations if you replaced every single module that's GPLed and DRMed with your own isolated modules, but that'd of course break the compatibility with the upstream-based stuff and would only work for very tailored scenarios. What I'm asking about is not actually linking, right? To link something I'd need to import kernel symbols. I could always create a self-isolated subsystem that just runs in kernelspace but works on its own without importing stuff from the kernel, as long as I'm willing to put the effort.