On Mon, 2026-09-14 at 13:31 +0100, Tvrtko Ursulin wrote: > On 14/09/2026 10:37, Philipp Stanner wrote:
[…] > > I took another look and I think my only issue is basically just that > > the patch addresses something which we should have done regardless of > > the bug at hands. So I'd be already happy if the commit just had a > > different title and slightly extended commit message, like: > > > > "drm/sched: Fix vruntime race by extending locking" > > > > plus sth like > > > > "this simultaneously serves as a preparational step to replace the > > spsc_queue as a whole". > > As I think it is fine as is I would prefer not to spend time on a respin > unless you insist. As I see it every patch that fixes something by moving or adding a lock solves a race condition. So we should call the child by the name. By calling it that we also publicly agree on our desire to extend locking and document in the log that drm_sched is moving towards that goal. If the effort bothers you too much, I could also apply it and thereby rephrase a bit. We can then request backmerge into misc-next and base the followup- cleanups on it. > > > > > Is there a plan btw as to how you would like to proceed with CFS? > > > > > > So for me the most typical and useful plan, and in the context of the > > > desired spsc removal, is: > > > > > > - Merge this fix so it gets into 7.2 > > > - Spsc removal RFC for some upcoming release N. > > > - Remove experimental status from fair policy for kernel release >= N. > > > - Switch fair to default at >= N+1. > > > > Couldn't it be enabled first for dedicated users? AFAIK it was > > developed with Steam's gaming platforms in mind. Can their OS devs be > > asked to switch it on or test it downstream? > > It wasn't quite developed for single game use cases, but with the wider > goal of improving the code base and DRM landscape in general. > > Also, I think it could give us false confidence since the matrix of > hardware + kernel setups is quite small. Even this bug wasn't caught on > an official platform, neither could I repro it on a Steam Deck. So I > would say a release or two after it is set as default is quite safe > since it can be easily reverted with a one line change. OK. P.
