GPL-2.0-or-later ?

Posted Nov 18, 2024 20:32 UTC (Mon) by andy_shev (subscriber, #75870)
In reply to: Hindsight... by dskoll
Parent article: Two approaches to tightening restrictions on loadable modules

And what to do with the modules that are using GPL-2.0-only symbols, but being licensed as GPL-2.0-or-later? Can GPL-3.0-or-later module use the symbols exported by those drivers?

GPL-2.0-or-later ?

Posted Nov 18, 2024 23:23 UTC (Mon) by rhbvkleef (subscriber, #154505) [Link] (1 responses)

GPL-2.0-or-later modules are not compatible with GPL-2.0-only. Strictly (and practically speaking) those must stop using GPL symbols or be relicensed to GPL-2.0-only. That makes the current MODULE_LICENSE("GPL") even more aggregeous.

GPL-2.0-or-later ?

Posted Nov 19, 2024 0:41 UTC (Tue) by Wol (subscriber, #4433) [Link]

> GPL-2.0-or-later modules are not compatible with GPL-2.0-only.

???

"2.0 or later" means the distributor can choose which licence to use. Which means they can distribute the kernel under 2.0, AND THEY CAN DISTRIBUTE THAT MODULE UNDER 2.0.

To be even more pedantic, they can NOT distribute that module under "2.0 or later" because that is not a licence!

> or be relicensed to GPL-2.0-only.

And no, that module can't (in all likelihood) be relicenced. Under normal circumstances (true of pretty much EVERY Free licence), the only person who can relicence code is the person who owns the copyright.

Copyright 101 - in order to copy and distribute code, you need a licence.
The "or later" wording is NOT a licence, it gives you permission to choose which licence YOU want to use.
When you distribute code from multiple owners in a "combined work", they must have given you compatible licences.
"GPL2 or later" gives you a GPL2 licence should you wish to use that licence.
GPL2 is compatible with GPL2, therefore you can distribute "GPL2 or later" code with GPL2 code, because YOU are using (legally) the same licence to distribute both codebases.

Cheers,
Wol