Comment 1 for bug 1656774

Reviewed: https://review.openstack.org/420146
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=86b361d9166200db2174be87214190a29e77f98f
Submitter: Jenkins
Branch: master

commit 86b361d9166200db2174be87214190a29e77f98f
Author: Lee Yarwood <email address hidden>
Date: Fri Jan 13 16:45:32 2017 +0000

    libvirt: workaround findmnt behaviour change

    findmnt as provided by util-linux-2.23.2-33 now returns 0 when --source
    is already mounted on the host under a different mountpoint [1]. This causes
    issues in environments where cinder-volume may have already mounted a
    given NFS share.

    This change works around this behaviour change by using os.path.ismount
    to confirm if the target is already a mountpoint and if a source is
    provided also checking /proc/mounts to confirm that it is mounted at the
    target location.

    [1] https://bugzilla.redhat.com/show_bug.cgi?id=1405238

    Closes-Bug: #1656774
    Change-Id: Id64cc77237bf770a9a75bbf666a54a604ace558c