Comment 4 for bug 1825386

Reviewed: https://review.opendev.org/348394
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=363710b655434a15b6b85d9ca65343210b104e56
Submitter: Zuul
Branch: master

commit 363710b655434a15b6b85d9ca65343210b104e56
Author: Dirk Mueller <email address hidden>
Date: Thu Jul 28 16:39:19 2016 +0200

    libvirt: Handle alternative UEFI firmware binary paths

    The OVMF binary paths differ based on the Linux distribution:

      - Debian and Ubuntu:
         - /usr/share/OVMF/OVMF_CODE.fd
      - Fedora:
         - /usr/share/edk2/ovmf/OVMF_CODE.fd
           (`symlink`s to /usr/share/OVMF/OVMF_CODE.fd)
         - /usr/share/edk2/ovmf/OVMF_CODE.secboot.fd (`symlink`s to
           /usr/share/OVMF/OVMF_CODE.secboot.fd)
      - CentOS and RHEL:
         - /usr/share/OVMF/OVMF_CODE.secboot.fd
      - SUSE:
         - /usr/share/qemu/ovmf-x86_64-opensuse-code.bin

    Currently, Nova only checks for one location OVMF_CODE.fd. Let's also
    check for the other two common distributions, SUSE and CentOS OVMF
    binary paths. This is a short-term solution to fix two bugs.

    In the long run:

      - We will get rid of the "DEFAULT_UEFI_LOADER_PATH", which is used to
        probe for firmware file paths. Instead, we'll use the more robust
        approach of the recently introduced[1] get_domain_capabilities()[1]
        to query for the firmware binary paths (as reported in the 'loader'
        attribute).

      - Use libvirt's (>=5.3) firmware auto-selection feature. Which is a
        more robust way to decide UEFI boot (secure or otherwise). More
        details of it in the spec here[2].

    [1] https://opendev.org/openstack/nova/commit/297f3ba687 -- Add
        infrastructure for invoking libvirt's getDomainCapabilities API
    [2] http://specs.openstack.org/openstack/nova-specs/specs/train/approved/allow-secure-boot-for-qemu-kvm-guests.html

    Co-Authored-By: Kashyap Chamarthy <email address hidden>
    Closes-Bug: 1607400
    Closes-Bug: 1825386
    blueprint: allow-secure-boot-for-qemu-kvm-guests
    Signed-off-by: Kashyap Chamarthy <email address hidden>
    Change-Id: I28afdb09d300be39981606d5234fd837ea738e1d