The OpenZFS project launches

Posted Sep 18, 2013 12:00 UTC (Wed) by drag (guest, #31333)
In reply to: The OpenZFS project launches by paulj
Parent article: The OpenZFS project launches

The CDDL license is a free software license that is incompatible with the GPL.

There is not much more to say about the subject then that.

It's not the first license to do that and it's not going to be the last. The only people that can do anything about it are either the Linux kernel developers or Oracle and that can only happen by them choosing to change the license.

The OpenZFS project launches

Posted Sep 19, 2013 5:54 UTC (Thu) by Blaisorblade (guest, #25465) [Link] (1 responses)

The project claims that they can distribute modules, just as anybody can distribute binary modules:
http://zfsonlinux.org/faq.html#WhatAboutTheLicensingIssue

How viable is that? Is there still a point in using the presumably slower ZFS-FUSE?

The OpenZFS project launches

Posted Sep 19, 2013 16:46 UTC (Thu) by drag (guest, #31333) [Link]

I would expect that it's viable if you compile it yourself and they don't ship any GPL-originated code with their code.

That is as long as their code is not derivative of Linux kernel code then the GPL cannot apply because that is outside the scope of copyright owned by the various Linux kernel devs.

Presumably once it's compiled it's going to pull in code from the kernel it's compiled against and then it would be a derivative product and falls under the scope of the GPL license. The GPL license, of course, itself says that it's restrictions only apply to distributed code and nothing that you use yourself. Therefore it would be legal to combine CDDL code and GPL (and produce a derivative of both) code as long as you don't distribute it since GPL doesn't restrict in this sort of usage.

The key here is 'derivative'. This is a legal term with specific definitions that is in the USA copyright code. It's a core concept to the copyright law itself. What is and what is not derivative is ultimately up to a court to decide. It's actually very arbitrary and don't expect it to always make logical sense so there may be some unexpected 'gotchas' and is why people pay money for lawyers to help interpret (which I am not one of them).

But ultimately, as long as the OpenZFS are fairly careful, then it's perfectly legal to distribute the code that you need to build your own modules. This is similar to the situation with the Nvidia binary driver.

The OpenAFS file system drivers for Linux have similar legal situation also. It's distributed under the IBM Public License which the FSF claims is incompatible with the GPL.

From FSF's license comparison website: 'This is a free software license. Unfortunately, it has a choice of law clause which makes it incompatible with the GNU GPL.'

Pretty much the same boat as the CDDL for the subject under discussion. OpenAFS support is a pretty normal feature that distributions support.

ie:

% yum search openafs |grep $(uname -r)
kmod-openafs-3.10.11-200.fc19.x86_64.x86_64 : openafs kernel module(s) for
: 3.10.11-200.fc19.x86_64

Although you'd have to look at the code of OpenZFS vs OpenAFS and talk to a lawyer to be fairly sure. Some kernel modules will violate the GPL even if they were in source code format. It's a very case-by-case situation.