Re: [PATCH v4 2/3] checkpatch: warn when Reported-by: is not followed by Link:

[Dmitry Vyukov]

On Thu, 2 Mar 2023 at 10:04, Thorsten Leemhuis <linux@xxxxxxxxxxxxx> wrote:
>
> On 02.03.23 09:27, Dmitry Vyukov wrote:
> > On Thu, 2 Mar 2023 at 06:40, Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
> >> On Thu, 2 Mar 2023 06:17:22 +0100 Thorsten Leemhuis wrote:
> >>> On 02.03.23 05:46, Jakub Kicinski wrote:
> >>>> On Fri, 20 Jan 2023 13:35:19 +0100 Thorsten Leemhuis wrote:
> >>>>> Encourage patch authors to link to reports by issuing a warning, if
> >>>>> a Reported-by: is not accompanied by a link to the report. Those links
> >>>>> are often extremely useful for any code archaeologist that wants to know
> >>>>> more about the backstory of a change than the commit message provides.
> >>>>> That includes maintainers higher up in the patch-flow hierarchy, which
> >>>>> is why Linus asks developers to add such links [1, 2, 3]. To quote [1]:
> >>>>
> >>>> Is it okay if we exclude syzbot reports from this rule?
> >>>> If full syzbot report ID is provided - it's as good as a link.
> >>>
> >>> Hmmm. Not sure. Every special case makes things harder for humans and
> >>> software that looks at a commits downstream. Clicking on a link also
> >>> makes things easy for code archaeologists that might look into the issue
> >>> months or years later (which might not even know how to find the report
> >>> and potential discussions on lore from the syzbot report ID).
> >>
> >> No other system comes close to syzbot in terms of reporting meaningful
> >> bugs, IMHO special casing it doesn't risk creep.
> >>
> >> Interestingly other bots attach links which are 100% pointless noise:
> >>
> >> Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
> >> Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4174
> >>
> >> Oh, eh. Let's see how noisy this check is once the merge window is over.
> >>
> >>> Hence, wouldn't it be better to ask the syzbot folks to change their
> >>> reporting slightly and suggest something like this instead in their
> >>> reports (the last line is the new one):
> >>>
> >>> ```
> >>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> >>> Reported-by: syzbot+bba886ab504fcafecafe@xxxxxxxxxxxxxxxxxxxxxxxxx
> >>> Link: https://lore.kernel.org/r/cafecaca0cafecaca0cafecaca0@xxxxxxxxxx/
> >>> ```
> >>>
> >>> This might not be to hard if they known the message-id in advance. Maybe
> >>> they could even use the syzbot report ID as msg-id to make things even
> >>> easier. And for developers not much would change afaics, they just need
> >>> to copy and paste two lines instead of one.
> >>
> >> Dmitry, WDYT?
> >
> > Adding a Link to syzbot reports should be relatively trivial.
>
> Sounds good.
>
> > Ted proposed to use Link _instead_ of Reported-by:
> > https://github.com/google/syzkaller/issues/3596
> >> in fact, it might be nice if we could encourage upstream developers
> >> put in the commit trailer:
> >> Link: https://syzkaller.appspot.com/bug?id=5266d464285a03cee9dbfda7d2452a72c3c2ae7c
> >> in addition to, or better yet, instead of:
> >> Reported-by: syzbot+15cd994e273307bf5cfa@xxxxxxxxxxxxxxxxxxxxxxxxx
> >
> > We could also use a link in the Reported-by tag, e.g.:
> >
> > Reported-by: https://syzkaller.appspot.com/b/5266d464285a03cee9db
> >
> > Some folks parse Reported-by to collect stats.
> >
> > What is better?
>
> Here are my thoughts:
>
> * we should definitely have a "Link:" to the report in lore, as that's
> the long-term archive under our own control and also where discussions
> happen after the report was posted; but I'm biased here, as such a tag
> would make tracking with regzbot a no-brainer ;)
>
> * "Reported-by:" IMHO should stay for the hat tip and stats aspects; I
> don't care if it includes the syzbot report ID or not (omitting it might
> be good for the stats aspects and is more friendly to the eyes, but
> those are just details)
>
> * a Link: to the syzkaller web ui might be nice, too -- and likely is
> the easiest thing to look out for on the syzbot server side
>
> IOW something like this maybe:
>
> Reported-by: syzbot+cafecafecaca0cafecafe@xxxxxxxxxxxxxxxxxxxxxxxxx
> Link: https://lore.kernel.org/r/cafecafecaca0cafecafe@xxxxxxxxxx/
> Link: https://syzkaller.appspot.com/b/cafecafecaca0cafecafe
>
> Something like the following would look more normal, but of course is
> only possible if syzbot starts out to look for such Link: tags (not sure
> if the msgid is valid here, but you get the idea):
>
> Reported-by: syzbot@xxxxxxxxxxxxxxxxxxxxxxxxx
> Link:
> https://lore.kernel.org/r/syzbot+cafecafecaca0cafecafe-syzkaller-appspotmail-com@xxxxxxxxxx/

Oh, you mean lore link.

We can parse out our hash from any tag, but the problem is that the
current email api we use, does not allow to specify Message-ID before
sending, so we don't know it when generating the text.
We don't even know it after sending, the API is super simple:
https://pkg.go.dev/google.golang.org/appengine/mail
So we don't know what the lore link will be...