The Debian init system general resolution returns

Posted Nov 2, 2014 15:27 UTC (Sun) by nix (subscriber, #2304)
In reply to: The Debian init system general resolution returns by viro
Parent article: The Debian init system general resolution returns

This also seems problematic from another perspective: fs namespaces. What good is it sending info out about init's mount namespace when there's no guarantee at all that it corresponds to the view anything else has of the filesystem? Any process that's looking at mounts other than by looking at /proc/self/mounts (or a symlink to it, e.g. /proc/mounts) and then considering that it need have any relevance to *its* state, rather than to the state of the process that did that read(), is just asking for subtle and horrible bugs.

The same applies to anything at all related to network interfaces.

Presumably this traffic is meant to be consumed by udev, i.e. it's a replacement for the existing in-kernel uevent messages over the netlink socket. Seems like a rather baroque, ludicrous, and bug-prone change to me.

The Debian init system general resolution returns

Posted Nov 2, 2014 16:33 UTC (Sun) by raven667 (subscriber, #5198) [Link]

I doubt the implementation is so dumb that its leaks inappropriate information across namespaces, systemd pid 1 manages the namespaces for services to it should have awareness of what goes where, but I don't think either of us is an expert on the implementation. There isn't anything here prevents a process from reading this information directly if it wants to, the real use case are applications which already use dbus for IPC, subscribing to a new structured message rather than implementing their own opening polling and parsing logic, or their own uevent subscription, which seems like a win to me.

The Debian init system general resolution returns

Posted Nov 2, 2014 17:08 UTC (Sun) by viro (subscriber, #7872) [Link] (1 responses)

As far as I can see, it boils down to wanting to be The Authority And The Source Of All Information. Nevermind that subjects^Wmanaged^Weverybody else can get the same thing easily; it seems to go against some very strong instincts. Same style as spamming everyone in the company with pointless memos on every thinkable topic, relevant or not...

There's a very strong smell of PHB all over the design. Worse, a PHB that had been told by some conslutant about Web 2.0 and social media being The Thing for millenial generation and decided to have a local equivalent of twitter built for communication with the plebes. It doesn't work well? Why, let's move it to the critical servers; those are on beefier intertubes, or something... Still doesn't work well? Too fucking bad for those who maintain those servers - it's their responsibility now (and of course, any questions regarding the basic design of the damn thing are countered with generous loads of "we had it behave that way before, therefore it must behave the same").

And yes, I am talking about dbus and plans of moving it kernel-side ;-/

The Debian init system general resolution returns

Posted Nov 2, 2014 21:35 UTC (Sun) by johannbg (guest, #65743) [Link]

Observing the kernel communication regarding the kdbus submission it's pretty clear that Eric would have nacked that proposal before the actual submission if that was possible.

That nack of his was a bit weird if you ask me but I guess I need to sacrifice a chicken, dance on one foot and drink some of that kernel koolaid to get my mind into the kernel cult and communication.