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? > 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
