Building kernel packages in Launchpad

[Ryan Govostes]

I would like to publish a PPA with customized kernel packages that
track the official Ubuntu kernel releases. I am aiming to use
Launchpad's continuous integration service, but I've encountered some
challenges.

The first hurdle is identifying which repository and branch is updated
to contain the latest release kernel sources. For linux-meta
(lp:ubuntu/+source/linux-meta) there's a branch like
applied/ubuntu/focal-security but linux just has a master branch. I
did find lp:~ubuntu-kernel/ubuntu/+source/linux/+git/focal which seems
close, if slightly ahead.

Next, this repository does not contain a debian/control file so the
Launchpad build tool, git-build-recipe, is unable to process the
source tree. Because the 'run' instruction is disallowed on Launchpad,
it is not possible to run debian/rules clean.

It would be very useful to be able to use the same CI infrastructure
as virtually all other Ubuntu source packages. Are there any
enhancements we can consider either for the kernel source tree or
within Launchpad itself to address this situation?

Thanks,
Ryan