Cannot boot if bdm specifies to create a new volume from an image or a snapshot

[Feodor Tersin]

Since that https://review.openstack.org/#/c/182994/ is merged, Cinder doesn't allow an empty volume name. But Nova specifies it for a new volume when the volume is created from a snapshot or a volume. Thus boot operation fails on compute node.

Steps to reproduce:
1 Boot an instance from a volume which should be autocreated from an image
nova boot inst --block-device source=image,dest=volume,bootindex=0,size=1,id=<cirros_id> --flavor m1.nano

2 Wait a bit and look at the instance state
nova show inst

Expected result: the instance state is active.
Actual result: the instance state is error, current stage is block device mapping.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/213433

[Xing Yang (xing-yang)]

Fixed proposed to Cinder:

https://review.openstack.org/#/c/213723/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/213723
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=480b8737e3bec677fd76b68b8887efe5cb1ab8de
Submitter: Jenkins
Branch: master

commit 480b8737e3bec677fd76b68b8887efe5cb1ab8de
Author: John Griffith <email address hidden>
Date: Mon Aug 17 08:08:14 2015 -0600

    Allow 0 length name

    There are currently cases where nova for example
    creates volumes with a name of zero length. We
    can't just change that and break compatability.

    This patch just modifes the wsgi module to allow
    min length of zero again.

    Change-Id: I829a8b4d6773d1c646d07cccb36994370e1dbce9
    Closes-Bug: #1485198