Bug#810367: kmod-static-nodes.service fails without a dependency on kmod

[Helmut Grohne]

Source: systemd
Version: 215-17+deb8u2

Hi Martin, Michael and other systemd folks,

in another attempt at exploring systemd, I noticed that you can install
a base system with systemd without installing kmod. This is useful for
minimizing an installation when your kernel does not support module
loading. It is also useful when systemd's own module loading
capabilities via libkmod are sufficient.

When doing so however, kmod-static-nodes.service loudly fails finding
kmod. I argue that this is a bug in the systemd packaging. Either that
service is optional. In this case it should gain a ConditionPathExists.
Or it is required for running the system. In which case systemd should
gain a runtime dependency on kmod. In the former scenario recommending
kmod still looks like a good idea to me.

In my embedded use case, the service actually creates an empty
/run/tmpfiles.d/kmod.conf and is thus not necessary for proper
operation. Thus I have a slight preference for the former solution. At
the same time I understand that the latter is easier to support.

I am reporting this bug against the jessie version, because I discovered
it there, but it applies to the unstable version as well. I do not think
this is worth fixing in jessie as it is a corner case and has trivial
workarounds.

Helmut

PS: For better serving the embedded, it would be nice if systemd could
    provide a smaller installation size (i.e. making more components
    optional). I understand splitting that systemd in more packages and
    making some of them optional is considerable amount of work and I
    have little suggestions on how to do that, but maybe you have. Maybe
    logind or the some of the dbus support (as dbus is already optional)
    could be moved somewhere else? Of course the default installation
    should keep these components.