ubuntu-cpc: Don't build minimized artifacts that won't boot with linux-kvm

[Dan Watkins]

Currently, the ubuntu-cpc hooks execute for all builds, minimized or not. As minimized images use the linux-kvm kernel, we shouldn't produce images for non-KVM platforms. The hooks that need skipping are the ones that produce the VMDK, OVA and Vagrant box.

Given that livecd-rootfs own the definition of minimized images, it should also own defining which images should be produced when a minimized build runs.

[Impact]

* Increased build time for minimized images
* Publication of minimized cloud images that cannot possibly boot

[Test Case]

Run a minimized livefs build; the .vmdk, .ova and .box files should not be produced. Run a regular livefs build, the .vmdk, .ova and .box files should be produced.

[Regression Potential]

The changes required are adding conditional "exit 0"s to the hooks in question, which aren't used by any other hooks. The only potential regression would be either (a) syntax issues that would manifest obviously in a complete failure to build (and therefore cause the Test Case to fail), or (b) accidental exclusion of these image types for non-minimized builds, which is covered in the Test Case section.

[Dan Watkins (oddbloke)]

Attached debdiff that addresses this in xenial.

[Dan Watkins (oddbloke)]

Nominated for xenial; minimized images are only produced for {xenial,bionic}, so that's sufficient.

[Dan Watkins (oddbloke)]

I've tested both the attached bionic branch and the attached xenial debdiff from a PPA.

[Dan Watkins (oddbloke)]

Attached a xenial MP after it was pointed out to me that we have a branch for xenial's livecd-rootfs.

[Steve Langasek (vorlon)]

Hello Dan, or anyone else affected,

Accepted livecd-rootfs into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/livecd-rootfs/2.408.28 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Launchpad Janitor (janitor)]

This bug was fixed in the package livecd-rootfs - 2.512

---------------
livecd-rootfs (2.512) bionic; urgency=medium

  * ubuntu-cpc: When performing a minimized build, don't generate artifacts
    that won't boot with the linux-kvm kernel (LP: #1757223).

 -- Daniel Watkins <email address hidden> Tue, 20 Mar 2018 13:42:50 -0400

[Dan Watkins (oddbloke)]

I've built images from -proposed and confirmed that the behaviour as as expected.

[Launchpad Janitor (janitor)]

This bug was fixed in the package livecd-rootfs - 2.408.28

---------------
livecd-rootfs (2.408.28) xenial; urgency=medium

  * ubuntu-cpc: When performing a minimized build, don't generate artifacts
    that won't boot with the linux-kvm kernel (LP: #1757223).

 -- Daniel Watkins <email address hidden> Tue, 20 Mar 2018 12:42:25 -0400

[Steve Langasek (vorlon)]

The verification of the Stable Release Update for livecd-rootfs has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.