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[[!meta title="AF_BUS, D-Bus, and the Linux kernel"]]

Might be interesting to watch how this develops.

[[!toc]]


# IRC, freenode, #hurd, about 2010-08/2010-09

    <neal> check this out:
    <neal> someone is working on implementing dbus in linux
    <neal> linux finally gets mach ipc ;-)
    <marcusb> it's old news though, unless there is an update
    <marcusb> and I think it was only the client?
    <neal> youpi : someone is adding dbus ipc to the linux kernel
    <neal> marcusb: I just heard about it.
    <youpi> (it's crazy how this drives backward compared to a hurdish approach)
    <youpi> what is the motivation for moving to the kernel?
    <neal> context switch overhead
    <azeem_> they wanna use it to talk to device drivers? :)
    <kilobug> well, they did that with the in-kernel web server, but they
      abandonned it later on
    <neal> azeem: I don't think so.
    <neal> dbus in the kernel is actually good for the Hurd as dbus IPC is
      basically neutered Mach IPC
    <marcusb> I don't think anybody wants to put the dbus server in the kernel
    <neal> well, there is at least one person
    <marcusb> maybe this is a different news from the one I read
    <neal> Alban Crequy (albanc) is working out.  He works for collabora, fwiw

<http://alban.apinc.org/blog/2010/09/15/d-bus-in-the-kernel-faster/>

    <marcusb> what I read was about hal etc
    <marcusb> so that you don't need a user space daemon to glue the kernel to the
      dbus world
    <neal> I don't think that is what he is talking about
    <marcusb> I can't find it anymore though.  I mentioned it in this channel at
      the time though, so it should be in the backlog
    <marcusb> neal, yeah could very well be a separate thing
    <marcusb> neal, dbus does have marginal support for fd passing though, and some
      attempts on the mailing list to make "fds" an official type in the message
      failed (as far as I could see, I didn't read the whole discussion)
    <marcusb> so no mach ipc just yet
    <neal> wrong
    <neal> FD handling is in 1.4
    <neal> type o, if I'm not mistaken
    <marcusb> then the discussion moved on from initial rejection
    <neal> no, 'h'
    <marcusb> I'm out of date by two months
    <marcusb> ok
    <guillem> neal: AFAIR Marcel Holtmann talked about dbus in-kernel several years
      ago, but he never ended up implementing it, or there were rumors he had
      private "working code"

  * Related Mailing List Discussion

      * [\[PATCH 0/5\] RFC: Multicast and filtering features on
        AF_UNIX](http://article.gmane.org/gmane.linux.kernel/1040481),
        2010-09-24


# 2013-02

[AF_BUS, D-Bus, and the Linux
kernel](http://www.kroah.com/log/linux/af_bus.html), Greg Kroah-Hartman,
2013-02-08.