[ithkuil]

IANAL, but if you create a derivative work of GPL v2 code you have to release it as GPL v2. This doesn't mean you, the copyright holder, cannot release it also with another license. The GPL forces you to ensure that people can use your extension of the original code with the same rules of the original code.

In case of kernel modules, if you distribute a binary built with kernel headers (like distributions do, then the sources of that kernel module have to be available under the the GPL license.

But if you distribute the sources of a kernel module, and each user compiles it, you can legally load it into a kernel without breaking the GPL. That's how ZFS can legally run on linux as a native module. I don't know if that's really necessary, but better safe than sorry.

Distributions can automate this compilation step so that from the point of view of the end user it doesn't make any difference, just a nuisance to the package maintainers (and yes, a few more mb of downloads for compilers and such).

[btilly]

IANAL, but if you create a derivative work of GPL v2 code you have to release it as GPL v2. This doesn't mean you, the copyright holder, cannot release it also with another license.

Sorry, not true.

The whole point of it being a derivative work is that someone else is also a copyright owner. If you release under a different license, you're saying that you give permission on their work. You can SAY that, but you're wrong.