OpenZFS's License

[zwynd]

OpenZFS is a project to implement the Zettabyte FileSystem in an open source repo. It has modules to work on Linux funded by the Lawrence Livermore National Laboratory .

I still don’t really get the whole license debacle though. I know that the CDDL license it has is not fully GPLv2 compatible, so it can’t be integrated into the Linux kernel - but it’s still a free software license, it’s approved by both the OSI and the FSF.

I’ve heard it’s just potential legal incompatibilities and it’s not even a certain thing. I’ve also heard it gives Oracle full control of the project, making them some kind of puppetmaster from the shadows that could pull the rug at any time.

Is it really that bad? I’ve read the terms, I personally dislike weak copyleft licenses, but I can get why such a project chose it. It doesn’t really seem “unsafe” to me, just different.

[d9b8]

It’s not that bad, and given that ZFS is a great piece of software, I think it’s worth using regardless of the slight incompatibility.

[lanodan]

@zwynd

I’ve also heard it gives Oracle full control of the project, making them some kind of puppetmaster from the shadows that could pull the rug at any time.

I guess you mean revoking the license, which for public licensing sounds seriously unrealistic. CDDL doesn’t explicitly forbids revocation (like most licences tend to have) but it does have this clause which seems rather similar:

4.2. Effect of New Versions.

You may always continue to use, distribute or otherwise make the
Covered Software available under the terms of the version of the
License under which You originally received the Covered Software.
If the Initial Developer includes a notice in the Original
Software prohibiting it from being distributed or otherwise made
available under any subsequent version of the License, You must
distribute and make the Covered Software available under the
terms of the version of the License under which You originally
received the Covered Software. Otherwise, You may also choose to
use, distribute or otherwise make the Covered Software available
under the terms of any subsequent version of the License
published by the license steward.

And so far from what I’ve grasped of the license incompatibility, it means you can’t distribute them both at the same product (so can’t be mainlined), but as a separated package that users would install it seems fine (which is what Ubuntu, Alpine, … are doing).

After all it’s also the level of separation you’d need for other third-party modules with GPLv2-incompatible licensing like VirtualBox modules (GPLv3 and GPLv2 being incompatible with each others^[1]), but also full-on proprietary ones like the nvidia drivers.

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1. Frequently Asked Questions about the GNU Licenses - GNU Project - Free Software Foundation ↩︎