Re: [PATCH 00/12] Add kdbus implementation

[Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>]

On Wed, Oct 29, 2014 at 04:11:06PM -0700, Greg Kroah-Hartman wrote:
> On Thu, Oct 30, 2014 at 12:00:16AM +0100, Jiri Kosina wrote:
> > On Wed, 29 Oct 2014, Greg Kroah-Hartman wrote:
> > 
> > > kdbus is a kernel-level IPC implementation that aims for resemblance to
> > > the the protocol layer with the existing userspace D-Bus daemon while
> > > enabling some features that couldn't be implemented before in userspace.
> > 
> > I'd be interested in the features that can't be implemented in userspace 
> > (and therefore would justify existence of kdbus in the kernel). Could you 
> > please point me to such list / documentation?
> 
> Lennart has given whole talks about this in the past, here's a recent
> talk going into the details:
> 	https://www.youtube.com/watch?v=HPbQzm_iz_k
> 
> > It seems to me that most of the highlight features from the cover letter 
> > can be "easily" (for certain definition of that word, of course) 
> > implemented in userspace (vmsplice(), sending fd through unix socket, user 
> > namespaces, UUID management, etc).
> 
> We have dbus in userspace today, but that requires extra copies of data,
> and isn't easy, or even possible, to do some of the application-specific
> bus logic that kdbus provides.  See the talk above for details, there
> are slides around somewhere with just text that we can add to the cover
> letter if that will help out in future spins of this patch series.

Here's an article describing it as well:
	https://lwn.net/Articles/580194/