[QUESTION] What is the best license option for new files introduced in QEMU?

[QUESTION] What is the best license option for new files introduced in QEMU?

[Aleksandar Markovic]

I read LICENSE file, but I read also recent contributions, and it is
not clear to me what version of GPL is best/recommended for new file
just being introduced to QEMU:

* GPL 2.0
* GPL 2.0 (or later at your option)
* GPL 2.1
* GPL 2.1 (or later at your option)

or something else. (The rest od wording of license preamble is clear
to me.) Please somebody explsin snd clarify.

Thanks,
Aleksandar

Re: [QUESTION] What is the best license option for new files introduced in QEMU?

[Aleksandar Markovic]

On Mon, Nov 25, 2019 at 6:49 PM Aleksandar Markovic
<aleksandar.m.mail@gmail.com> wrote:
>
> I read LICENSE file, but I read also recent contributions, and it is
> not clear to me what version of GPL is best/recommended for new file
> just being introduced to QEMU:
>
> * GPL 2.0
> * GPL 2.0 (or later at your option)
> * GPL 2.1
> * GPL 2.1 (or later at your option)
>

Thomas pointed to me that I mixed up GPL and LGPL - which is true.

Still, the question remains with these options:

* GPL 2.0
* GPL 2.0 + wording "or later (at your option)"
* LGPL 2.1
* LGPL 2.1 + wording "or later (at your option)"

The context of my question is that I am reviewing a series that came
with files with different license preambles (or without it at all), and I
want to advice the submitters on the best option.

Sincerely,
Aleksandar

> or something else. (The rest od wording of license preamble is clear
> to me.) Please somebody explsin snd clarify.
>
> Thanks,
> Aleksandar

Re: [QUESTION] What is the best license option for new files introduced in QEMU?

[Eric Blake]

On 11/25/19 1:25 PM, Aleksandar Markovic wrote:

> Thomas pointed to me that I mixed up GPL and LGPL - which is true.
> 
> Still, the question remains with these options:
> 
> * GPL 2.0

Not good. It artificially limits who can reuse this code.

> * GPL 2.0 + wording "or later (at your option)"

Matches what qemu itself uses, so fine; but makes it harder to reuse the 
code in a standalone library.

> * LGPL 2.1

Same problems as GPL2-only

> * LGPL 2.1 + wording "or later (at your option)"

Looser than qemu as a whole, has all the benefits of GPL2+ plus the 
additional benefit of being able to copy the code into other LGPL 
standalone libraries.

It's also acceptable to use even looser licenses, like BSD 2-clause, but 
preferably only if that other license is already used by part of qemu 
(we don't need to make our mix even worse than it already is).

> 
> The context of my question is that I am reviewing a series that came
> with files with different license preambles (or without it at all), and I
> want to advice the submitters on the best option.

You may also want advice from lawyers, based on how you see your code 
being reused outside of qemu.  This list can offer advice, but it is 
non-binding and may not best fit your needs.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org

Re: [QUESTION] What is the best license option for new files introduced in QEMU?

[Aleksandar Markovic]

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On Monday, November 25, 2019, Eric Blake <eblake@redhat.com> wrote:

> On 11/25/19 1:25 PM, Aleksandar Markovic wrote:
>
> Thomas pointed to me that I mixed up GPL and LGPL - which is true.
>>
>> Still, the question remains with these options:
>>
>> * GPL 2.0
>>
>
> Not good. It artificially limits who can reuse this code.
>
> * GPL 2.0 + wording "or later (at your option)"
>>
>
> Matches what qemu itself uses, so fine; but makes it harder to reuse the
> code in a standalone library.
>
> * LGPL 2.1
>>
>
> Same problems as GPL2-only
>
> * LGPL 2.1 + wording "or later (at your option)"
>>
>
> Looser than qemu as a whole, has all the benefits of GPL2+ plus the
> additional benefit of being able to copy the code into other LGPL
> standalone libraries.
>
> It's also acceptable to use even looser licenses, like BSD 2-clause, but
> preferably only if that other license is already used by part of qemu (we
> don't need to make our mix even worse than it already is).
>
>
>> The context of my question is that I am reviewing a series that came
>> with files with different license preambles (or without it at all), and I
>> want to advice the submitters on the best option.
>>
>
> You may also want advice from lawyers, based on how you see your code
> being reused outside of qemu.  This list can offer advice, but it is
> non-binding and may not best fit your needs.
>
>
I truly appreciate your response!

-- 
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3226
> Virtualization:  qemu.org | libvirt.org
>
>

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Re: [QUESTION] What is the best license option for new files introduced in QEMU?

[Thomas Huth]

On 25/11/2019 18.49, Aleksandar Markovic wrote:
> I read LICENSE file, but I read also recent contributions, and it is
> not clear to me what version of GPL is best/recommended for new file
> just being introduced to QEMU:
> 
> * GPL 2.0
> * GPL 2.0 (or later at your option)
> * GPL 2.1
> * GPL 2.1 (or later at your option)
> 
> or something else. (The rest od wording of license preamble is clear
> to me.) Please somebody explsin snd clarify.

There is no GPL v2.1, you likely mixed that up with LGPL v2.1

For new files, you've got to choose a license that is compatible with 
GPL v2.0 (or later at your option). So LGPL v2.1 is fine, too.

  Thomas

Re: [QUESTION] What is the best license option for new files introduced in QEMU?

[Markus Armbruster]

Aleksandar Markovic <aleksandar.m.mail@gmail.com> writes:

> I read LICENSE file, but I read also recent contributions, and it is
> not clear to me what version of GPL is best/recommended for new file
> just being introduced to QEMU:

The situation is confusing.  It's a mess of our own making.

> * GPL 2.0
> * GPL 2.0 (or later at your option)
> * GPL 2.1
> * GPL 2.1 (or later at your option)
>
> or something else. (The rest od wording of license preamble is clear
> to me.) Please somebody explsin snd clarify.

Let's not add to the mess: GPLv2+ unless you have a compelling reason to
deviate, spelled out in your commit message.

In my opinion, accepting GPLv2-only contributions was a mistake.