Comment 1 for bug 1642628

Reviewed: https://review.openstack.org/398479
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=d55c5136d0f7ece722db889a4375133e827411c0
Submitter: Jenkins
Branch: master

commit d55c5136d0f7ece722db889a4375133e827411c0
Author: Lee Yarwood <email address hidden>
Date: Wed Nov 16 15:51:02 2016 +0000

    libvirt: Detach volumes from a domain before detaching any encryptors

    I983f80822a5 introduced retry logic around the detaching of volumes from
    a libvirt domain. However it also reordered the surrounding code so that
    we attempt to detach any encryptors from a volume first while the volume
    is still attached to the domain. This can lead to `Device or resource
    busy` errors if the volume is still being used by the instance when we
    attempt to detach the encryptors.

    Closes-bug: #1642628
    Change-Id: Ia0f8e725ec8a0fbc44bd4592b021dea978cf4e4f