Off-topic: D-Bus in the kernel
marcel at holtmann.org
Fri Sep 17 22:06:22 PDT 2010
> > > You should really consider using something else for the sockaddr. It can
> > > be as simple as an unique integer automatically assigned when listen()
> > > gets called, fetched with getsockname(). As an added bonus, it becomes
> > > trivial to start DBus early in the boot.
> > Actually the kernel should just start the system bus. No reason to wait
> > for userspace. That way we can remove all needed magic handling in init
> > daemons like systemd. The D-Bus system bus is just present and always
> > present as long as the kernel is running.
> That would assume the kernel can handle everything that you'd expect from the
> bus. I doubt that's going to happen. For a start, DBus activation cannot be
> done from the kernel alone, just like modprobe.
that is not a problem at all. The kernel could just craft a D-Bus
message and send it off to systemd (or upstart for that matter). That
being the init process will then just start the daemon and babysit it.
And of course with kernel managing the bus users, it knows when systemd
has been started and attached itself to the bus. Also since systemd is
the init process the kernel also knows when that got started anyway.
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