Comment 19 for bug 1750829

Reviewed: https://review.openstack.org/565670
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=efa26e8dc24b5e828447fb78d0f54004054ae8b9
Submitter: Zuul
Branch: stable/pike

commit efa26e8dc24b5e828447fb78d0f54004054ae8b9
Author: Kashyap Chamarthy <email address hidden>
Date: Sat Apr 28 18:55:25 2018 +0200

    libvirt: Make `cpu_model_extra_flags` case-insensitive for real

    When we introduced `cpu_model_extra_flags` config attribute (in
    commit: 6b601b7 -- "libvirt: Allow to specify granular CPU feature
    flags"), we said it was case-insensitive; but unfortunately I missed to
    _really_ make it so (despite proposing code for it in one of the
    revisions).

    Address that mistake by making `cpu_model_extra_flags` case-insensitive
    for real, from Nova's point of view.

    NB: Internally, this patch is normalizing 'extra_flags' to _lower_
    casing -- because CPU flags _must_ be lower case from libvirt's point of
    view. Nova must honour that; otherwise, launching instances with an
    upper case CPU flag, 'FOO', will fail with: "libvirtError: internal
    error: Unknown CPU feature FOO".

    Related-Bug: #1750829
    Change-Id: Ia7ff0566a5109c76c009f3a0c6199c4ba419cfb1
    Reported-by: Daniel P. Berrangé <email address hidden>
    Signed-off-by: Kashyap Chamarthy <email address hidden>
    (cherry picked from commit 8e438eda9bb16cdd3b627b93da2435572275b921)
    (cherry picked from commit f9ab466c6d9bb657409356f29139a9edfbb98747)