On Sun, Sep 30, 2018 at 1:52 PM, Hans de Goede <hdegoede@xxxxxxxxxx> wrote: > Hello Fedora kernel team, > > On the Fedora desktop list there has been a discussion about > systemd now offering a new suspend-then-hibernate option and > gnome-settings-daemon's media-keys plugin using this when > the power-button gets pressed and systemd saying this is > available on the system. > > What this does is suspend the system normally and set > a RTC wakeup 3 hours in the future, then when the RTC wake > happens it hibernates the system. > > As discussed on the desktop list this is not really desirable > as default behavior for F29 (and later) since the hibernate > code is not really something which gets used enough to be > well tested and is really not something which we can support. > > So after that the discussion has gone in the direction of > how to disable the new suspend-then-hibernate behavior. > > Lennart made a really interesting observation here, systemd > is just proxying if "cat /sys/power/disk" indicates that > hibernate is supported. > No, that is not what systemd is doing. The kernel provides a mechanism, it does absolutely nothing with that mechanism unless told to do so. What systemd is actually doing is creating a policy around that mechanism. > So if we really don't want to support hibernation as a normal > option, while still allowing adventurous user to use it, what > really should happen is for the kernel to stop advertising > hibernate support. Thinking about this I agree, if we say > that we cannot support it, the kernel really should not be > advertising support for it by default. > "We have decided that the policy created is not desirable, so we want to disable the mechanism" > So Bastien suggested to change the nohibernate setting in > kernel/power/hibernate.c which can be set from the kernel > commandline to default to 1, and allow setting it back > to 0 by adding "hibernate=yes" to the kernel commandline. > > I kinda like this idea and I'm willing to spend some time > to write a patch for this and submit it upstream, which allows > selecting nohibernate=1 as the default through Kconfig. > > But before I spend (some) time on this, I wonder what the > kernel team's opinion on this is ? > > My own 2 cents on this are: > > Pro: > > Not advertising hibernate by default means users will not > accidentally try to use it (through e.g gnome-tweaks) and if > they do use it by specifying the kernel commandline option > we can easily explain that using that commandline option is > not supported by Fedora and kindly request them to file bugs > upstream. TL;DR: less kernel issues for Fedora to deal with, > good. > > Against: > > Currently we do have some users using hibernation without > adding any options to the kernel commandline. These users > will have to now add "hibernate=yes" to their kernel commandline. > > I'm thinking that yes we want this, but maybe this needs to > go through the change process for proper communication, so for > F29 we need another fix, and we can do this for F30? > While this change would "solve" the problem, I do not believe it is the correct place to do so. As mentioned above, the mechanism is not flawed. Some hardware does not support the mechanism, and has no way of reporting as such, which is why policy has always been leave it off unless the user knowingly triggers it. Now we have changed the policy, in a way that seems pretty much universally undesirable, the solution is the revert the policy, not cripple the mechanism. Justin _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/kernel@xxxxxxxxxxxxxxxxxxxxxxx
