Re: Issues with capability bits and meta-data in kdbus

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Apr 22, 2015 at 07:40:25AM -0400, Austin S Hemmelgarn wrote:
> On 2015-04-21 22:32, Linus Torvalds wrote:
> >On Tue, Apr 21, 2015 at 6:54 PM, Andy Lutomirski <luto@amacapital.net> wrote:
> >>
> >>If kdbus were a general purpose IPC tool
> >
> >  .. but it's not ..
> >
> 
> Except, IIRC, that was one of the stated design goals in the original patch
> set.  I'm pretty sure that i remember a rather verbose exposition that
> pretty much could be summarized as "Linux has no general purpose IPC in the
> kernel, this fixes that"

Did I say that somewhere?  Here's what the patchset has always started
with every time I have posted it for review, starting back last year in
October:

	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.

2+ years ago, I had the dream that maybe we could make kdbus into the
"general purpose IPC layer for the kernel", but in working through all
of the issues, and the requirements of the userspace users and
protocols, it just really didn't work out that way, sorry.

I know some people would like such a "general purpose IPC", but perhaps
because no one has ever done it, maybe it either can't be done, or that
no one really wants such a thing. :)

thanks,

greg k-h