Re: [Ksummit-discuss] Allowing something Change-Id (or something like it) in kernel commits

Greg Kroah-Hartman
2019-08-27T13:48:40Z

On Tue, Aug 27, 2019 at 06:24:36AM -0700, Dmitry Vyukov wrote:
> On Mon, Aug 26, 2019 at 11:06 PM Thomas Gleixner <tglx@linutronix.de> wrote:
> >
> > On Mon, 26 Aug 2019, Dmitry Vyukov wrote:
> > > A somewhat related point re UUID/Change-ID.
> > > For syzbot (or any other bug tracking system) we want to associate
> > > bugs with fixes. It turned out there is no good identity of a change
> > > that we could use. Commit hash is an obvious first thing to consider,
> > > but (1) it changes in linux-next, (2) sometimes the change is not
> > > committed yet when we do the association, (3) it is different when
> > > backported to LTS (so not possible to say if a fix is in that stable
> > > tree or not).
> > > We decided to use commit subject, which works to some degree, but also
> > > has problems: (1) not necessary unique, (2) sometimes people change
> > > subject during backporting (e.g. prepend some prefix), (3) has all the
> > > same problems of email clients messing with text (e.g. I can't issue
> > > #syz fix command for loo long commit subjects with my email client).
> > > Some real UUID/Change-ID would solve all of these problems by giving
> > > us capability to refer to changes rather than a commit in a particular
> > > tree only.
> >
> > If we adopt the Link: ..../$MSG tag widely then you have a UUID.
>
> Is there a way to ensure that everybody will generate right IDs
> (ChangeID-Version) and then a link in canonical form will be included
> into commit? As far as I understand this is not possible with the
> current kernel tooling, as this aspect is not under control of any
> unified tooling.
> I see different maintainers use links to different archive web sites.
> Also sometimes Link is present for other reasons (e.g. link to bug
> report).
> The link will need to be added by every developer (rather than
> maintainer) so that it's available before the change is committed
> anywhere.

For subsystems I maintain, I am already adding the Link: tag to
lore.kernel.org with the message id in it. That is automatically added
by my scripts.

> Though, most of these are problems for any other change identification scheme...

Note, we have 4000+ developers every year, it's hard enough to get them
all to agree on major things, let alone crazy stuff like this :)

thanks,

greg k-h