On Tue, May 25, 2021 at 9:04 AM Rodrigo Campos <rodrigo@xxxxxxxxxx> wrote: > > On Mon, May 17, 2021 at 9:39 PM Sargun Dhillon <sargun@xxxxxxxxx> wrote: > > > > This refactors the user notification code to have a do / while loop around > > the completion condition. This has a small change in semantic, in that > > previously we ignored addfd calls upon wakeup if the notification had been > > responded to, but instead with the new change we check for an outstanding > > addfd calls prior to returning to userspace. > > I understand why this was a readability improvement on the old > patchset (that included the wait_killable semantics), as it completely > changed the loop. But now we only have the atomic addfd+send reply > that does minimal changes to this part (add a param to a function). > > Is it worth changing the semantics? > I think that as we add more complexity around different things that can cause the notification to change (status), that this is better, but I understand wanting to hold off. > > Rodrigo Campos also identified a bug that can result in addfd causing > > an early return, when the supervisor didn't actually handle the > > syscall [1]. > > > > [1]: https://lore.kernel.org/lkml/20210413160151.3301-1-rodrigo@xxxxxxxxxx/ > > I was about to resend this, but I'd like to know what others think. > > I'm okay with applying any patches to solve the issue (mine linked > there or this one), slightly in favor of mine as the diff is way > simpler to backport (applies to 5.9+ kernels) and I don't see a reason > to change semantics. But no strong opinion. > > Opinions? > > > Best, > Rodrigo
