F21 System Wide Change: Modular Kernel Packaging for Cloud

[Jaroslav Reznik]

= Proposed System Wide Change: Modular Kernel Packaging for Cloud =
https://fedoraproject.org/wiki/Changes/Modular_Kernel_Packaging_for_Cloud

Change owner(s): Cloud SIG / Sandro Mathys <red at fedoraproject.org>, Kernel 
Team / Josh Boyer <jwboyer at fedoraproject.org>

Kernel modules that are not necessary in virtualized environments become 
optionally (un)installable. 

== Detailed Description ==
Space is precious in the cloud, therefore the Cloud SIG tries to keep the 
images' footprint as small as reasonably possible. Therefore, we'd like to 
split the kernel into two (plus one meta) packages. One package would contain 
the core modules, i.e. a minimum(-ish) set of drivers to only just be able to 
run in virtualized environments. And another package for the rest. The 
'kernel' package would then become a meta package that installs both (-core 
and -drivers). 

== Scope ==
Normal installations will continue installing the kernel (meta-)package and 
users should not notice any difference. Same goes for updating from earlier 
Fedora releases. But where desired, it should become possible to install only 
a reasonably minimal subset of kernel modules. Both kernel and kernel-core 
will Provide "kernel", therefore the "install instead of update" magic of 
yum/dnf will work as expected even if only kernel-core is installed.

* Proposal owners: The kernel package needs to be changed to produce a meta- 
(kernel) and two new packages (-core and -drivers) packages additionally to 
those already built out of the SRPM. Aside from the obvious changes to the 
package spec file, that includes evaluating what modules need to go into which 
package and making sure updating from pre-split kernel packages works as 
expected. Most of this work has already been done but still requires some fine-
tuning: [1]

* Other developers: Anaconda must allow to install kernel-core instead of 
kernel, when using a kickstart file. (To gain full benefits of this change, but 
the change itself can be implemented without). Work has been done but is not 
well tested yet: [2]

* Release engineering: No changes necessary.
* Policies and guidelines: No changes necessary.

[1] http://copr-fe.cloud.fedoraproject.org/coprs/jwboyer/kernel-core/
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1074522