[Pkg-utopia-maintainers] Bug#747180: dbus reports CanSuspend/CanHibernate as false

[Simon McVittie]

retitle 747180 o.fd.PowerManagement reports CanSuspend = false
reassign 747180 kde-workspace-bin
thanks

On 06/05/14 09:38, Pawel Palucha wrote:
> As I understand, KDE queries dbus if the system is able to perform
> suspend/hibernate. This is what I get when I query dbus for suspend:
> 
> # dbus-send --print-reply --type=method_call \
> --dest="org.freedesktop.PowerManagement" \
> /org/freedesktop/PowerManagement \
> org.freedesktop.PowerManagement.CanSuspend
> 
> method return sender=:1.2 -> dest=:1.76 reply_serial=2
>    boolean false

That's not querying dbus, that's using D-Bus to query the
org.freedesktop.PowerManagement service.
<http://www.freedesktop.org/wiki/Specifications/power-management-spec/>
suggests that o.fd.PowerManagement used to be implemented by
gnome-power-manager and other desktops' equivalents, but
gnome-power-manager no longer has that interface. Presumably something
in a KDE session still does - based on codesearch.debian.net I'm
guessing it's probably in kde-workspace-bin.

>From there, you'd have to look into how your (KDE's?) implementation of
o.fd.PowerManagement answers that question; the answer to that is likely
to be "by asking a system service". That system service might be
something like upower, systemd or systemd-logind, for instance.

> May  6 10:33:53 hostname dbus[2078]: [system] Activating service
> name='org.freedesktop.systemd1' (using servicehelper)
> May  6 10:33:53 hostname dbus[2078]: [system] Activated service
> 'org.freedesktop.systemd1' failed: Launch helper exited with unknown
> return code 1

Something (probably your o.fd.PowerManagement implementation) is trying
to send messages to org.freedesktop.systemd1, which is the D-Bus name
that systemd takes when it runs as process 1. However, it looks as
though your process 1 is probably sysvinit or something, not systemd.
(Is that true?)

I don't know KDE well, but I would guess that the package information in
the output of

reportbug --template libsolid4
reportbug --template kde-workspace-bin

would be useful here.

It seems that xfce4-power-manager also implements o.fd.PowerManagement,
so it would also be useful if you could confirm whether you have that
installed. If you have both, dbus-daemon will pick one or the other for
activation, arbitrarily (there's no order of preference or anything).

KDE maintainers: is KDE suspend/hibernate still expected to work on
systems where process 1 is not systemd?

Regards,
    S