On Fri, Dec 28, 2018 at 09:06:24AM +0100, Pavel Machek wrote: > On Mon 2018-12-03 23:22:46, Thomas Backlund wrote: > > Den 2018-12-03 kl. 11:22, skrev Sasha Levin: > > > > > > > > This is a case where theory collides with the real world. Yes, our QA is > > > lacking, but we don't have the option of not doing the current process. > > > If we stop backporting until a future data where our QA problem is > > > solved we'll end up with what we had before: users stuck on ancient > > > kernels without a way to upgrade. > > > > > > > Sorry, but you seem to be living in a different "real world"... > > I have to agree here :-(. > > > People stay on "ancient kernels" that "just works" instead of updating > > to a newer one that "hopefully/maybe/... works" > > Stable has a rules community agreed on, unfortunately stable team just > simply ignores those and decided to do "whatever they please". > > Process went from "serious bugs that bother people only" to "hey, this > looks like a bugfix, lets put it into tree and see what it breaks"... Resulting in us having to tell users not to use stable kernels because they can contain broken commits from upstream that did not go through maintainer tree and test cycles. https://marc.info/?l=linux-xfs&m=154544499507105&w=2 In this case, the broken commit to the fs/iomap.c code was merged upstream through the akpm tree, rather than the XFS tree and test process as previous changes to this code had been staged. It was then backported so fast and released so quickly that it hadn't got back into the XFS upstream tree test cycles until after it had already committed to at least one stable kernel. We'd only just registered and confirmed a regression in in post -rc7 upstream trees when the stale kernel containing the commit was released. It took us another couple of days to isolate failing configuration and bisect it down to the commit. Only when I got "formlettered" for cc'ing the stable kernel list on the revert patch (because I wanted to make sure the stable kernel maintainers knew it was being reverted and so it wouldn't be backported) did I learn it had already been "auto-backported" and released in a stable kernel in under a week. Essentially, the "auto-backport" completely short-circuited the upstream QA process..... IOWs, if you were looking for a case study to demonstrate the failings of the current stable process, this is it. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
