Linus on GPLv3 and ZFS

Posted Jun 12, 2007 19:23 UTC (Tue) by dlang (guest, #313)
In reply to: Linus on GPLv3 and ZFS by ajross
Parent article: Linus on GPLv3 and ZFS

GPLv2 and GPLv3 are not compatible in either direction

the only thing that lets GPLv2 code change to GPLv3 is if people gave the FSF a blank check and said 'GPLv2 or later'

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Linus on GPLv3 and ZFS

Posted Jun 12, 2007 21:04 UTC (Tue) by man_ls (guest, #15091) [Link] (6 responses)

True:

When we say that GPLv2 and GPLv3 are incompatible, it means there is no legal way to combine code under GPLv2 with code under GPLv3 in a single program. This is because both GPLv2 and GPLv3 are copyleft licenses: each of them says, If you include code under this license in a larger program, the larger program must be under this license too. There is no way to make them compatible.

Linus on GPLv3 and ZFS

Posted Jun 13, 2007 8:20 UTC (Wed) by forthy (guest, #1525) [Link] (5 responses)

The FSF took great efforts that GPL versions can be made compatible. The paragraph that deals with it is section 9 of the GPL. Read it, especially the last part - many files in the Linux kernel are not explicitely restricted to a specific GPL versions, which means "any version". And section 6 makes sure that everybody receives a license from the original licensor, not from a compilation editor like Linus Torvalds.

The compilation editor (Linus Torvalds) can set terms under which he redistributes the work, i.e. conditions he has to follow. But since everybody receives the license from the original licensors, this "restriction" is null and void, you still can make a compilation yourself which does not restrict the license version, and then, most parts of Linux are compatible with GPLv3 (because you can either choose any GPL or explicitely v2 or later).

Linus on GPLv3 and ZFS

Posted Jun 13, 2007 9:37 UTC (Wed) by man_ls (guest, #15091) [Link] (4 responses)

That kind of compatibility is not much help, unless all of the kernel is licensed as "v2 or later". As long as there is a single file licensed under "v2 only", it becomes impossible to link with a single "v3 only" file.

Meanwhile, relicensing all files under a "v2 or later" license might seem to be a necessary first step to a GPLv3 kernel. But given Linus' reluctance to blanket license, I would rather expect a "dual v2-v3" license, if the migration is to be done at all.

Linus on GPLv3 and ZFS

Posted Jun 13, 2007 13:09 UTC (Wed) by job (guest, #670) [Link] (3 responses)

Maaaybe there was a good reason why the FSF recommended the use of "v2 or later" licensing. Then you basically leave the choice to the user. I never understood what Linus didn't like about that, except some unspecified fear of the FSF, which would be not only ridicolous but also unfortunate.

Linus on GPLv3 and ZFS

Posted Jun 13, 2007 13:36 UTC (Wed) by man_ls (guest, #15091) [Link] (1 responses)

It is not so unreasonable: Linus said:

How can you _ever_ sign anything sight unseen? That's just stupid, and that's totally regardless of any worries about the FSF.

Said that way, it looks like the correct thing to do. However, given that (as you say) "v2 or later" licensing gives the choice to the user, I'm not particularly worried about misuse.

Linus on GPLv3 and ZFS

Posted Jun 13, 2007 21:56 UTC (Wed) by notamisfit (guest, #40886) [Link]

It creates the possibility that code created in a downstream work may not be usable upstream. Linus has put his cards on the table in the past; he wants code back.

Linus on GPLv3 and ZFS

Posted Jun 14, 2007 1:59 UTC (Thu) by error27 (subscriber, #8346) [Link]

Instead of "ridiculous and unfortunate" I would say "justified by current events."