[fab] Non-standard kernels in the Fedora Multiverse

[Rahul Sundaram]

On Mon, 2006-05-08 at 15:53 -0400, Greg DeKoenigsberg wrote:
> As some of you may know, I've been talking with Fernando Lopez-Lezcano 
> about bringing Planet CCRMA officially under the Fedora banner.
> 
> Fernando has taken up the challenge, and is taking a lot of the initial 
> steps.  He's moving to use yum instead of apt-get.  He's giving the spec 
> files for his packages to Extras folks for review.  Things are moving.
> 
> The sticking point, though, will be the kernel.  High-end audio 
> applications absolutely require the lowest latency possible, so Fernando 
> is rolling his own kernels with Ingo Molnar's real time patches.  These 
> aren't mainline yet, and they aren't likely to be in the foreseeable 
> future.  They also can't be abstracted out into separate kernel modules, 
> from what I've been able to divine.
> 
> Therefore: we have no mechanism currently to deliver Fernando's kernel.
> 
> At least, that's what I thought -- until I learned that Fedora Core is 
> actually shipping a non-standard kernel for Xen.  If you want to run a 
> dom0 box, you boot into the Xen kernel.
> 
> Which brings up a few questions for me:
> 
> 1. If it's okay for RH to put nonstandard kernels into Fedora, then 
> shouldn't it be okay for the community to put nonstandard kernels into 
> Fedora?  If not, why not?
> 

It should be except that it doesnt fit into our agenda ;-). More
seriously though, we already had that discussion before and there are
some concerns.  It would nice to get Ingo's patchset in more wider use
and it might help in upstream adoption but we need to think about
solving a few problems

* Do we allow all kinds of alternative kernels to be packaged in Fedora?
* How do we avoid kernel maintainers ending up with unrelated bug
reports?
* How much commitment do we have to from alternative kernel maintainers
to continue maintaining them and fix security issues etc in a timely
manner?
* Do kernel modules being packaged in Fedora Extras and Core work across
these different kernels?



> 2. Do we keep the Xen kernel close to the standard Fedora kernel?  If so, 
> how do we do that?

Lot of painful grunt work from what I can see.

> 
> I'd really like to be able to make Planet CCRMA a standard Fedora install 
> by FC7.  Is it possible?

* Would it be possible for the applications to even work without the RT
patchset in Fedora?  

* How many different source packages are there in Planet CCRMA? 

* How many reviewers are interested in professional audio applications
in Fedora Extras?

Rahul