Karmic i386 flavour changes

[Andy Whitcroft]

On Tue, Jun 16, 2009 at 11:14:31PM +0100, Colin Watson wrote:
> On Tue, Jun 16, 2009 at 02:05:35PM -0600, Tim Gardner wrote:
> > The next upload will be an ABI bump to 2.6.30-10.11
> > 
> > Pursuant to the Karmic flavours Blueprint
> > https://blueprints.launchpad.net/ubuntu/+spec/kernel-karmic-flavours
> > I've implemented the flavour changes.
> > 
> > However, I have some questions about upgrading as well as CPU feature
> > detection.
> > 
> > 1) Is the installer intelligent enough to detect the relevant CPU
> > features necessary to support PAE, and therefore install the correct
> > kernel version ? (Or at least complain that PAE is not supported).
> 
> Not yet, but it's easy to make it so, especially if somebody tells me
> the thing I need to look for in /proc/cpuinfo. Is it just "pae"?
> 
> The trickier issue is that in order for this to be a useful choice, we
> now need to cram two kernels onto our CDs, otherwise either (a) non-PAE
> users are just screwed or (b) PAE users don't get any advantage unless
> they install via netboot or a DVD. Has this been discussed? I don't see
> a record of it in the specification.

If we cannot fit two kernels onto the CD would we be able to have the
non-pae kernel on the disk, but be able to suggest an update to the
appropriate kernel, perhaps using the network for that?  For example
could we have a linux-legacy on the disk as normal and a linux-generic-0
which is just a placebo and gets upgraded on the next network upgrade
and triggers the switch?

Also how do we currently handle updates if you are an actual 386 compiled
kernel currently?

Finally while taking this into account, it would be nice to consider the
very oldest users who as a quirk of the old->hardy->later upgrade process
would have been updated from original i386 kernel to the 386 compiled
ports kernel, who would rather have remained on generic.

> BTW,
> http://www.mail-archive.com/fedora-kernel-list@redhat.com/msg01682.html
> is what I was referring to obliquely at UDS. Maybe somebody should poke
> Kyle and find out if he has the patch set to hand.

Thanks for the pointer.

-apw