Re: Non-GPL export of invalidate_mmap_range

Christoph Hellwig
2004-02-18T23:00:55Z

On Wed, Feb 18, 2004 at 02:51:32PM -0800, Andrew Morton wrote:
> a) Does the export make technical sense? Do filesystems have
> legitimate need for access to this symbol?
>
> (really, a) is sufficient grounds, but for real-world reasons:)
>
> b) Does the IBM filsystem meet the kernel's licensing requirements?
>
>
> It appears that the answers are a): yes and b) probably.

Well, the answer to b) is most likely not. I see it very hard to argue to
have something like gpfs not beeing a derived work. The glue code they
had online certainly looked very much like a derived work, and if the new
version got better they wouldn't have any reason to remove it from the
website, right?

> Please, feel free to add additional criteria. We could also ask "do we
> want to withhold this symbols to encourage IBM to GPL the filesystem" or
> "do we simply refuse to export any symbol which is not used by any GPL
> software" (if so, why?).

Yes. Andrew, please read the GPL, it's very clear about derived works.
Then please tell me why you think gpfs is not a derived work.

> But at the end of the day, if we decide to not export this symbol, we owe
> Paul a good, solid reason, yes?

Yes. We've traditionally not exported symbols unless we had an intree user,
and especially not if it's for a module that's not GPL licensed.

We had this discussion with Linus a few time, maybe he can comment again to
make it clear.