Re: [Qemu-devel] We need more reviewers/maintainers!!

[Anthony Liguori]

On 03/12/2012 01:03 PM, Lluís Vilanova wrote:
> Stefano Stabellini writes:
> [...]
> > Patches are being posted to the list that don't get any reviews at all.
> > Other patches get reviewed the first time, then once they are reposted
> > they don't get any other reviews or acked-by or reviewed-by.
>
> What are the different tags available and what is their semantic? Maybe this
> should be written down somewhere (HACKING?).
>
> I'll contribute a starting list of tags
> (http://wiki.x.org/wiki/Development/Documentation/SubmittingPatches), please
> check these are the desired semantics for this project.
>
> * Cc: Full Name<email>
>
>    In addition to sending the patches to the mailing list, they must be Cc'ed 
> to,
>    at least, the maintainers for the affected files. You can look up the
>    maintainers for each file in the MAINTAINERS file.
>
>    The command "git send-email" will automatically look for such a tag in order
>    to send a CC of the mail to the given person.
>
>    Document maintainer discovery with 'scripts/get_maintainer.pl'?
>
>
> * Acked-by: Full Name<email>
>
>    If a person was not directly involved in the preparation or handling of a
>    patch but wishes to signify and record their approval of it then they can
>    arrange to have an Acked-by: line. Acked-by: does not necessarily indicate
>    acknowledgement of the entire patch.
>
>
> * Tested-by: Full Name<email>
>
>    A Tested-by: tag indicates that the patch has been successfully tested (in
>    some environment) by the person named. This tag informs maintainers that some
>    testing has been performed, provides a means to locate testers for future
>    patches, and ensures credit for the testers.
>
>
> * Reviewed-by: Full Name<email>
>
>    A Reviewed-by tag is a statement of opinion that the patch is an appropriate
>    modification without any remaining serious technical issues. Any interested
>    reviewer (who has done the work) can offer a Reviewed-by tag for a patch.
>
>
> My understanding until now was that both Acked-by and Reviewed-by were tags
> reserved to people with privileges to write into the repository.

That's interesting feedback.  These are all documented throughly in Linux's 
SubmittingPatches (which I think ours refers to).

Specifically:

13) When to use Acked-by: and Cc:

The Signed-off-by: tag indicates that the signer was involved in the
development of the patch, or that he/she was in the patch's delivery path.

If a person was not directly involved in the preparation or handling of a
patch but wishes to signify and record their approval of it then they can
arrange to have an Acked-by: line added to the patch's changelog.

Acked-by: is often used by the maintainer of the affected code when that
maintainer neither contributed to nor forwarded the patch.

Acked-by: is not as formal as Signed-off-by:.  It is a record that the acker
has at least reviewed the patch and has indicated acceptance.  Hence patch
mergers will sometimes manually convert an acker's "yep, looks good to me"
into an Acked-by:.

Acked-by: does not necessarily indicate acknowledgement of the entire patch.
For example, if a patch affects multiple subsystems and has an Acked-by: from
one subsystem maintainer then this usually indicates acknowledgement of just
the part which affects that maintainer's code.  Judgement should be used here.
When in doubt people should refer to the original discussion in the mailing
list archives.

If a person has had the opportunity to comment on a patch, but has not
provided such comments, you may optionally add a "Cc:" tag to the patch.
This is the only tag which might be added without an explicit action by the
person it names.  This tag documents that potentially interested parties
have been included in the discussion


14) Using Reported-by:, Tested-by: and Reviewed-by:

If this patch fixes a problem reported by somebody else, consider adding a
Reported-by: tag to credit the reporter for their contribution.  Please
note that this tag should not be added without the reporter's permission,
especially if the problem was not reported in a public forum.  That said,
if we diligently credit our bug reporters, they will, hopefully, be
inspired to help us again in the future.

A Tested-by: tag indicates that the patch has been successfully tested (in
some environment) by the person named.  This tag informs maintainers that
some testing has been performed, provides a means to locate testers for
future patches, and ensures credit for the testers.

Reviewed-by:, instead, indicates that the patch has been reviewed and found
acceptable according to the Reviewer's Statement:

        Reviewer's statement of oversight

        By offering my Reviewed-by: tag, I state that:

         (a) I have carried out a technical review of this patch to
             evaluate its appropriateness and readiness for inclusion into
             the mainline kernel.

         (b) Any problems, concerns, or questions relating to the patch
             have been communicated back to the submitter.  I am satisfied
             with the submitter's response to my comments.

         (c) While there may be things that could be improved with this
             submission, I believe that it is, at this time, (1) a
             worthwhile modification to the kernel, and (2) free of known
             issues which would argue against its inclusion.

         (d) While I have reviewed the patch and believe it to be sound, I
             do not (unless explicitly stated elsewhere) make any
             warranties or guarantees that it will achieve its stated
             purpose or function properly in any given situation.

A Reviewed-by tag is a statement of opinion that the patch is an
appropriate modification of the kernel without any remaining serious
technical issues.  Any interested reviewer (who has done the work) can
offer a Reviewed-by tag for a patch.  This tag serves to give credit to
reviewers and to inform maintainers of the degree of review which has been
done on the patch.  Reviewed-by: tags, when supplied by reviewers known to
understand the subject area and to perform thorough reviews, will normally
increase the likelihood of your patch getting into the kernel.

Regards,

Anthony Liguori

> Lluis