[Pkg-zfsonlinux-devel] [Soc-coordination] Possible GSoC idea: ZFS on Linux integration

[Aron Xu]

On Sat, Mar 2, 2013 at 1:51 AM, Paul Tagliamonte <paultag at debian.org> wrote:
> On Sat, Mar 02, 2013 at 01:44:59AM +0800, Aron Xu wrote:
>>
>> As for license concerns, ZoL is distributed in the form of two Linux
>> kernel modules, spl and zfs. The first one is Solaris Porting Layer,
>> licensed under GPL-2+, providing a set of system calls that is
>> compatible to Solaris; and the other one is the actual stuff of ZFS,
>> licensed under CDDL. In this way, both of the modules can be legally
>> distributed using dkms or pre-built binary modules.
>
> Are we sure about that? This seems like a tough call. I'm tempted to
> call SPL irrelevant on this (I mean, I don't know how it works, but if
> it's sharing memory with the CDDL, they're a combined work.
>

ZoL is designed carefully to avoid such license issue, AFAIK. SPL
provides a set of syscalls, also a header file when building it to
expose relevant information about the kernel, and later when building
the zfs module it will use the information from that header file.

Also a bit of background: ZoL is an independent Linux kernel module
developed by Lawrence Livermore National Laboratory (LLNL) under a
contract between U.S. Department of Energy and LLNL, and is separated
into two parts to avoid violating CDDL. A Solaris Porting Layer (SPL)
kernel module is developed to provide many of the Solaris kernel APIs,
and is licensed under GPL-2+, while the zfs modules are CDDL, reusing
existing OpenSolaris code and cooperate with BSDs and other projects.

> *can* we distribute it? We should ask the FTP* folks about this IMHO.
>
> I know there was concern about it never being able to become part of the
> Linux tree, and I do understand this is a different problem than that
> (well, mostly).
>

I think in DKMS form there's definitely no license problem, and as
confirmed by upstream there is no problem in distributing them in
binary form. Well zfs module is CDDL so it will "taint" the kernel
when loaded, though.

Anyway I'll ask FTP* folks soon.



-- 
Regards,
Aron Xu