On Fri, 31 May 2019, Josh Poimboeuf wrote: > > I disagree with that from the backwards compatibility point of view. > > > > I personally am quite frequently using differnet combinations of > > resumer/resumee kernels, and I've never been biten by it so far. I'd guess > > I am not the only one. > > Fixmap sort of breaks that invariant. > > Right now there is no backwards compatibility because nosmt resume is > already broken.
Yeah, well, but that's "only" for nosmt kernels at least. > For "future" backwards compatibility we could just define a hard-coded > reserved fixmap page address, adjacent to the vsyscall reserved address. > > Something like this (not yet tested)? Maybe we could also remove the > resume_play_dead() hack? Does it also solve cpuidle case? I have no overview what all the cpuidle drivers might be potentially doing in their ->enter_dead() callbacks. Rafael? Thanks, -- Jiri Kosina SUSE Labs
