Comment 3 for bug 1730641

Reviewed: https://review.openstack.org/443548
Committed: https://git.openstack.org/cgit/openstack/diskimage-builder/commit/?id=271dc36f33e1a2e8774167cd592639fbf98597c0
Submitter: Zuul
Branch: master

commit 271dc36f33e1a2e8774167cd592639fbf98597c0
Author: Zhiguo Deng <email address hidden>
Date: Wed May 10 23:09:42 2017 -0400

    Add zipl element as s390x architecture bootloader

    s390x architecture uses zipl as bootloader. When used in combination
    with the vm element it replaces the existing bootloader element.
    It's mandatory for s390x vm images.

    Use cases
    ---------

    * Allow users to create s390x images that run on nova with s390x
      libvirt/kvm backend
    * Building nodepool images for s390x third party CI

    Supported Distros
    -----------------
    The following listing shows all Distros that officially support
    s390x and how those Distros are supported in DIB with this patch.

    * SLES - not supported (SLES is not supported in DIB)
    * RHEL - not suppoprted (RHEL is not supported as KVM guest on s390x,
                             therefore there's no rhel7 qcow image for s390x available
                             like it is for other archictectures)
    * Ubuntu - supported

    Ubuntu images can for example be built using the following commands:

      $ disk-image-create ubuntu-minimal zipl vm
      $ disk-image-create ubuntu-minimal zipl
      $ disk-image-create ubuntu zipl vm

    Testing
    -------

    Cross architecture building of s390x images is not supported so far.

    The plan is to set up a ThirdParty CI that builds the image for s390x and
    provides the logs.

    Co-Authored-By: Andreas Scheuring <email address hidden>
    Co-Authored-By: Holger Smolinsky <email address hidden>
    Co-Authored-By: Zhiguo Deng <email address hidden>
    Co-Authored-By: Arne Recknagel <email address hidden>

    Closes-Bug: #1730641

    Change-Id: I576e7edda68da12e97c60af38f457915efe7b934