Re: Proposal: Enhancing Commit Tagging for Stable Kernel Branches

[Takashi Iwai <tiwai@suse.de>]

On Thu, 18 Jul 2024 00:05:06 +0200,
Dan Carpenter wrote:
> 
> On Tue, Jul 16, 2024 at 02:20:42PM +0200, Takashi Iwai wrote:
> > > > > The one question I have is for patches which pre-date git.  I was told
> > > > > to leave the Fixes tag off in that case, but I think that's out of date.
> > > > > It's more useful to say "Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")".
> > > > 
> > > > If a thing was there since before git and only now is being discovered
> > > > it either needs to be explicitly marked for stable with cc: or we can
> > > > just keep the fix in newer kernels. IMO this particular "Fixes" tag does
> > > > not bring any value.
> > > 
> > > On the contrary, if I see just a "cc: stable" and no "Fixes:" tag, I do
> > > a "best effort" to backport to all current stable/lts trees.  If it
> > > fails on 5.15 and older, great, I don't warn anyone about that as there
> > > was no Fixes: tag for me to know how far back it should go.
> > 
> > That's what I expected for the cases I put only Cc-to-stable; they
> > have been mostly some trivial quirks only for new devices, and the
> > stuff that can be taken safely when applicable -- otherwise just
> > skip.
> > 
> 
> That's the same thing that happens if you add the Fixes: 1da177e4c3f4
> ("Linux-2.6.12-rc2") tag.  Greg and Sasha aren't manually backporting
> patches unless they seem security related.  When a patch doesn't
> backport cleanly, the stable maintainers rely on other people to backport
> patches they care about.

Well, in my case, it's not always Fixes:Linux-2.6.12-rc2; the relevant
code has been often added later.  But pointing somewhere new as Fixes
also won't work, since there are other dependent fixes.  And tracking
all those is really hard, and not worthy.  It's a thing that can be
backported safely whenever it's cleanly applied and built, but
otherwise it can be simply skipped.  It's no "regression", per se, but
a new feature that didn't exist in the past, after all.

That said, if a change is important and should be inevitably
backported to stable, I'd point Fixes tag, too.


thanks,

Takashi