Re: [PATCH] USB: mark USB drivers as being GPL only

[David Newall <davidn@davidnewall.com>]

Hans-Jürgen Koch wrote:
> The license says that derivative work has to be GPL. Naturally, every
> sensible and practically usable license has gray areas. We know that
> and we live with that. But if there's room for interpretation, it's
> perfectly OK and helpful, if the copyright holder states what his
> interpretation is. If you use an EXPORT_SYMBOL_GPL symbol in non-GPL
> code, you know that the owner of the work doesn't agree with you
> license-wise.

How can an author form the opinion that another work is derivative, when
it hasn't even necessarily been written yet?

EXPORT_SYMBOL_GPL is no statement of the author's beliefs.  It's an
algorithm of restriction, and it affects original, non-derivative works.

>> It requires software that is *distributed* as part of a GPL
>> work to itself be GPL.  At time of distribution, a kernel module is
>> neither using nor linked to the kernel.
>>     
>
> Oh, come on! You cannot turn a derived work into an original work just
> by distributing them seperately.

That's not what I said.  From the start, I've made clear that I'm
talking of original, non-derivative works.  You said that mere linking
makes that non-derivative work derivative:

> Using a symbol from a library means linking to it, and that creates a
> derived work. Why should it be different when using kernel symbols?


This is wrong for the reasons I stated.