Comment 5 for bug 1920237

Reviewed: https://review.opendev.org/c/openstack/cinder/+/789859
Committed: https://opendev.org/openstack/cinder/commit/3bb28c637e98078a4da2b6930e56bfce0cce9f73
Submitter: "Zuul (22348)"
Branch: stable/train

commit 3bb28c637e98078a4da2b6930e56bfce0cce9f73
Author: Eric Harney <email address hidden>
Date: Fri Mar 19 16:01:33 2021 +0000

    Backup manager: Synchronously call remove_export

    Call the volume's rpcapi remove_export method with
    a "call" instead of a "cast" when detaching volumes
    in the backup manager.

    This prevents _detach_volume() from returning before
    the remove_export() has completed, which helps prevent
    problems where remove_export() races against a
    subsequent operation.

    Closes-Bug: #1920237

    Change-Id: I482c3d5520a7bbb9971942cdb4c4208052106d70
    (cherry picked from commit d6895f9d2aab84c116efc2f853bb5f9e57fac539)
    (cherry picked from commit 5402ac8e2d30872b526c3ac7d9f10645452fbf66)
    (cherry picked from commit 34120d49808537d0523375b173db9c657114a4cb)