Bug#800521: systemd: sys-kernel-config.mount not functional

[Ferenc Wagner]

Michael Biebl <biebl at debian.org> writes:

> Or, the dlm packages ships a modules-load.d snippet in
> /usr/lib/modules-load.d where it loads the configfs mdoule, since it's
> the dlm package which apparently needs configfs, not systemd itself.

Well, this is the point where we obviously differ: in my opinion, the
sys-kernel-config.mount unit provided by systemd needs configfs.  Not in
the technical sense because of the ConditionPathExists=/sys/kernel/config
directive, which I find historical baggage hiding the problem and tripping
the outsiders.  If that wasn't there, the issue would be much more clear
cut.  But I think in the practical sense it still is, and systemd should
ensure that pulling in sys-kernel-config.mount results in configfs being
available under its standard mount point.  (I think the kernel could as
well expose the /sys/kernel/config mount point unconditionally, even if
configfs is a not yet loaded module or even disabled, but I digress.)

Basically, it all boils down to the meaning of sys-kernel-config.mount.  I
don't know what else requires or will require a mounted configfs, but it
should not need to care about configfs being modules or built in, or the
path of its standard mount point.  Putting Require=sys-kernel-config.mount
(and After=) should take care of that, concentrating all the system-
specific knowledge into the system manager.  After all, stuff should
preferably work even under a user-compiled monolithic kernel.  I'm not
sure how to best handle that, but certainly in the central module loader,
not in the individual packages providing stuff.

Please forgive me pushing this so stubbornly; maybe I'd just need to sleep
on it.
-- 
Regards,
Feri.