Re: [Ksummit-discuss] [MAINTAINERS SUMMIT] Bug-introducing patches

[Guenter Roeck <linux@roeck-us.net>]

On Fri, Sep 07, 2018 at 03:27:01PM -0700, Linus Torvalds wrote:
> On Fri, Sep 7, 2018 at 2:13 PM Sasha Levin via Ksummit-discuss
> <ksummit-discuss@lists.linuxfoundation.org> wrote:
> >
> > 1. Grab a batch of ~2-3 week old commits from Linus's tree.
> > 2. Review, basic tests and send stable-rc notification.
> 
> Side note: maybe the stable grabbing and testing could be automated?
> 
> IOW, right now the stable people intentionally (generally) wait a week
> before they even start. Maybe there could be an automated queue for
> "this has been marked for stable" (and the whole "fixes:" magic that
> you guys already trigger on) that gets applied to the previous stable
> tree, and starts testing immediately.
> 
> Because one of the patterns we *do* obviously see is that something
> was fine in mainline, but then broke in stable because of an unforseen
> lack of depdenencies. Sure, it's probably pretty rare (and *many*
> dependencies willl show up as an actual conflict), but I think the
> times it does happen it's particularly painful because it can be so
> non-obvious.
> 
> So maybe an automated "linux-next" that starts happening *before* the
> rc stage would catch some things?
> 

And it does, as soon as Greg publishes a set of patches. At the very
least 0day runs on those, as well as my builders. There is a question
of scalability, though. I am sure that will improve over time as more
test resources become available, but six stable releases plus mainline
plus next plus whatever contributing branches covered by 0day and others
does take a lot of resources.

Personally I would suggest to further improve test coverage, not to add
more branches to test. More hardware for sure, but also adding more tests
such as the network testing suggested by Sasha.

Guenter