On Mon, Jul 15, 2019 at 11:16 AM Linus Torvalds <torva...@linux-foundation.org> wrote: > > On Mon, Jul 15, 2019 at 5:29 AM Jason Gunthorpe <j...@mellanox.com> wrote: > > > > The 'hmm' tree is something I ran to try and help workflow issues like > > this, as it could be merged to DRM as a topic branch - maybe consider > > this flow in future? > > > > Linus, do you have any advice on how best to handle sharing mm > > patches? > > I don't have a lot of advice except for "very very carefully". > > I think the hmm tree worked really well this merge window, at least > from my standpoint.
Side note: I suspect that having a separate branch maintained by a separate person actually does help the "very carefully" part. I think the hmm branch ended up getting more "incidental review" simply because of how it was done. So even if the original reason for the separate branch was to resolve some quilt/git integration issues, I would not be at all surprised if just the extra indirection through another person ended up making both the sending and receiving side think more about each patch and think more about the abstraction. The hmm branch didn't actually seem to have any of the core VM people reviewing it either, but it did have reviewers across companies for all the patches, and I do think that that makes a difference. It's _soo_ easy for a patch series to be developed inside one company by a couple of people who are probably in the same group, and have the exact same objectives, to be a lot more biased (and likely biased not towards the mm goals, but the goals of the code _outside_ the mm). This is just a long-winded way to say "I do think that the separate and external branch with multiple interested parties" can have some inherent advantages, when you actually have multiple people looking at it with care and intent. (And here the fact that you have multiple subsystems looking at the code is very much part of what makes it a good model - if it was just an external branch for one single user - the vmware gfx driver - you wouldn't get the same kind of advantages. So it's not the "external branch" part itself, it's the "multiple users who care" part that likely causes people to think more about the end result) Again - maybe I'm rationalizing, and the hmm branch just randomly happened to work well this time. I do like having multiple people from different groups look at things, though. Linus _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel