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

[Marek Olšák]

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:

"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.

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