[Mesa-dev] [RFC] Mesa 9.2 and release process changes

[Ian Romanick]

On 07/08/2013 03:12 PM, Marek Olšák wrote:
> On Tue, Jul 2, 2013 at 10:02 PM, Ian Romanick <idr at freedesktop.org> wrote:
>> 3. I'd like to make some adjustments to our process for picking patches back
>> to the stable branch.  The current process is okay, but it has some kinks.
>> The two big (related) problems are people either under-mark things for the
>> stable branch or over-mark.  We also have the problem that things are
>> occasionally marked for stable that, in the end, shouldn't go to stable.
>>
>> Instead of the current system, I'd like to propose creating a mesa-stable
>> mailing list where candidate patches will be sent.  The release manage will
>> then have the responsibility to apply patches to the branch.  This gives
>> opportunity for subsystem maintainers to ACK or NAK patches before they
>> land.  It also gives the opportunity to use a build bot to pre-verify that
>> no patch ever breaks the build on the stable branch.
>>
>> Anyone can nominate a patch for stable by sending it to the list.  This
>> provides a means for solving the under-mark problem.  It may mean that
>> developers have to do more work (e.g., waiting awhile after a patch lands on
>> master to send it to the stable list), so we may need to come up with some
>> means to mitigate that.
>>
>> As part of this, we need to clearly document the criteria for inclusion in
>> the stable branch.  We have some vague criteria now, but we should formalize
>> and agree on the list.
>
> I don't like the idea that *we* have to send patches to the stable
> mailing list. The marking of candidates for stable has pretty much
> been the same as in the Linux kernel and worked pretty well. From
> kernel/Documentation/stable_kernel_rules.txt:

Yeah, I wasn't terribly in love with that part either.  Having to 
remember to send a patch out again seemed prone to loss.

> "To have the patch automatically included in the stable tree, add the tag
>    Cc: stable at vger.kernel.org
> in the sign-off area. Once the patch is merged it will be applied to
> the stable tree without anything else needing to be done by the author
> or subsystem maintainer."
>
> The major difference between the current Mesa and kernel approaches
> seems to be that there is a -stable maintainer for kernel who decides
> which candidates go in and which don't. I think we need such a strict
> maintainer for our stable branches, but I don't think we need anything
> else.

Carl has agreed to be the maintainer at least for the time being. 
Having a separate list would make it easier for him to sort candidate 
patches from non-candidate patches because would keep marked-at-commit 
patches and marked-after-commit patches in one places.

Could we just change our "Mark the patch with 'NOTE: ...'" policy with 
"To have the patch automatically included in the stable tree, add the tag
     Cc: mesa-stable at lists.freedesktop.org

in the sign-off area..." ?

> I also think the under-mark problem is unsolvable no matter what the
> process of picking patches is. People must either:
> - mark their patches for stable
> - go through the git log, find suitable candidates, and make sure they
> are all picked (I have done this with my patches too), this is the
> only case where a stable mailing list makes sense
>
> I also recommend reading stable_kernel_rules.txt as mentioned by
> Daniel Vetter, but he linked to an old version. The latest version can
> be found in the kernel tree.
>
> Marek