kdbus and Fedora

[Harald Hoyer]

On 05.05.2015 19:50, Josh Boyer wrote:
> Hi All,
> 
> Harald and I were recently talking about kdbus and how it plays into
> Fedora.  Right now, the kernel-playground COPR is carrying the kdbus
> patches, but that isn't widely used and isn't included in a broad test
> base. Obviously our distribution is heavily entwined with D-Bus and we
> were looking to see if it was possible to help kdbus testing and
> development by doing some kind of integration within Fedora itself.  I
> promised Harald I would talk it over with the other Fedora kernel
> maintainers and after a brief discussion we came up with the following
> possible proposal.
> 
> If Fedora were to carry kdbus in any form, the following things would
> be required:
> 
> 1) There would be a single canonical location to track kdbus
> development.  After talking with Harald, that should be the upstream
> tree that gregkh is using to submit patches.
> 
> 2) Harald's team (systemd, etc) would commit to testing the system
> both with and without kdbus active.  Obviously we do not want to
> enforce reliance on something as core critical as kdbus while it is
> still being actively developed upstream.  That could cause a lot of
> deviation down the road and it isn't the aim here.
> 
> 3) kdbus would only be carried in the rawhide branch until it is
> merged upstream.  As a concrete example, if kdbus was not merged in
> the upstream kernel at the time rel-eng creates the F23 branches, then
> Fedora 23 will never get kdbus.  It will be carried in rawhide and
> rawhide only until it's accepted upstream.  The maintainers actually
> hope this does get merged but we want to make sure we are prepared to
> drop this without causing too much trouble if needed.
> 
> 4) After discussing a bit with the rest of the Fedora kernel
> maintainers, we would carry an additional patch that would require
> 'kdbus-enabled' to be specified before the kernel would allow kdbus to
> be loaded (or similar mechanism).  This would focus the main testing
> effort for all the default images to remain as they are today, while
> easily allowing the plumbing layer developers access to kdbus for
> their enablement testing.
> 
> These conditions would hopefully help the Fedora kernel maintainers
> avoid some of the pitfalls of carrying a large chunk of out of tree
> code and if they're all met we feel fairly comfortable with doing
> this.  We wanted to send this out for a bit wider discussion and
> review before proceeding with it, and I agreed to start this thread so
> here we are.
> 
> Harald, does the above look like what you were envisioning when we
> talked earlier?
> 
> josh
> 

Looks very good except for point 4, where we wanted to enable kdbus by default
and have a "kdbus=0" command line option.

CC'ing the kdbus folks...