> > Indeed. Actually, one could argue that it's impossible to solve the > > problem as long as we try to call out to userspace during suspend and > > need to wait until that's finished, like in the case of sys_sync() and > > fuse filesystems, and probably other cases. Maybe we should make *those* > > calls return a failure so that the suspend isn't transparent inside the > > kernel but is transparent to userspace. > > Well, it generally needs more consideration. :-) > > I think that we should introduce mechanisms that will allow us to notify all > kernel subsystems, including FUSE and similar, that the system is going to > enter a sleep state (one of those is the notifier chain introduced recently). Ugh, please no. Believe me, fuse is doing _nothing_ out of the ordinary, and should not need special treatment during suspend/resume. If suspend itself is doing something that triggers fuse activity, then that's a bug, such as the sync() thing that started this thread. > Then, they may react to such a notification by entering a "suspend" mode > of operation in which they will return errors from some callbacks that > otherwise should have succeeded etc. That depends on the subsystem in > question. Sounds horrible. Why do we need to deal with subsystem interdependencies during suspend? Isn't it about saving device state to ram? That definitely _should not_ need to trigger anything that touches filesystems or other subsystems. Miklos _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
