Re: [PATCH 1/2] docs: introduce dedicated page about code provenance / sign-off

[Samuel Tardieu <sam@rfc1149.net>]

Daniel P. Berrangé <berrange@redhat.com> writes:

>> Is there any requirement for the order of tags?
>> 
>> My previous understanding was that if the Reviewed-by/Tested-by 
>> tags
>> were obtained by the author within his company, then those tags 
>> should
>> be placed before the signed-off-by of the author. If the 
>> Reviewed-by/
>> Tested-by were acquired in the community, then they should be 
>> placed
>> after the author's signed-off-by, right?
>
> Common practice is for Signed-off-by tags to be kept in time 
> order
> from earliest author to latest author / maintainer. Common case 
> is
> 2 S-o-B, the first from the patch author, and the last from the
> sub-system maintainer who sends the pull request.
>
> For other tags I don't see any broadly acceptable pattern. Some 
> people
> add Reviewed-by before the S-o-B, others add Reviewed-by after 
> the
> S-o-B. Either is fine IMHO.

From what I've seen in other projects, S-o-B means that you accept 
accountability for everything above. One scenario would be:

- Send original patch, which has been tested inside the company:

  Tested-by: Tester <tester@example.com>
  Signed-off-by: Developper <developper@example.com>

- Get some R-b, but need to make some requested minor changes and 
  resend a new patch series:

  Tested-by: Tester <tester@example.com>
  Reviewed-by: Reviewer <reviewer@othercompany.com>
  Signed-off-by: Developper <developper@example.com>

  This is a way of saying "I guarantee that the R-b still applies 
  after the new changes I made to this series"

- Then reviewed and pulled into their tree by the maintainer:

  Tested-by: Tester <tester@example.com>
  Reviewed-by: Reviewer <reviewer@othercompany.com>
  Signed-off-by: Developper <developper@example.com>
  Reviewed-by: Maintainer <maintainer@org.org>
  Signed-off-by: Maintainer <maintainer@org.org>

If, after being reviewed, the initial patch would not have needed 
any change, the order would have been:

  Tested-by: Tester <tester@example.com>
  Signed-off-by: Developper <developper@example.com>
  Reviewed-by: Reviewer <reviewer@othercompany.com>
  Reviewed-by: Maintainer <maintainer@org.org>
  Signed-off-by: Maintainer <maintainer@org.org>

This is consistent with what software like "b4" do: if the S-o of 
the current user is present, it is moved last, as the current user 
is the one accepting accountability at this point.

However, this is not what QEMU has been using as far as I can see, 
as S-o-b tend to stay in their original positions. I even opened 
an issue on b4 a few weeks ago because of this 
<https://github.com/mricon/b4/issues/16>, and I reverted to using 
git-publish. But if this is ok to use an arbitrary order for 
non-S-o-b headers, I can get back to b4.

  Sam
-- 
Samuel Tardieu