[systemd-devel] systemd hibernator generator does not function on default Fedora install

[Andrei Borzenkov]

19.04.2016 01:19, James Hogarth пишет:
> Hi all,
> 
> There's been some discussion today about the impact of
> https://bugzilla.redhat.com/show_bug.cgi?id=1206936 and where the problem
> actually lies.
> 
> The issue lies specifically with hibernate and affects all Fedora systems
> regardless of hardware (it's reproducible in a VM).
> 
> The hibernate image gets written to swap correctly
> but hibernate-resume-generator.c looks specifically for 'resume' in
> /proc/cmdline to determine a) if any check shoudl even happen and b) which
> block device to check.
> 
> When Fedora is installed anaconda does not write a resume= line
> to GRUB_CMDLINE_LINUX in /etc/default/grub or to the default kernel stanza
> for grubby to later duplicate.
> 
> Dracut cmdline module does produce a resume= line but it appears this
> occurs too late for the generator to pick up.
> 

dracut cmdline is internal to dracut, so external programs do not see it.

> The end result is that without manual intervention to add an appropriate
> resume= line it's impossible to resume from hibernation on Fedora, and the
> critical battery behaviour (configured via /etc/Upower/Upower.conf and
> visible in upower -d) is to HybridSleep.
> 
> Is it feasible for systemd to have the generator pick a swap image
> regardless of resume being present or not? If so the dracut cmdline coming
> later than the hibernate generator wouldn't be a problem.
> 

Well, TBH the simplest solution is really to add resume= to kernel
command line. Otherwise let dracut install own generator that does
exactly the same when resume= is missing as real kernel parameter. In
both cases I do not think it is something that needs to be implemented
in systemd.