Volume Manager failed to start when some volumes are not found on the backend

[Huang Zhiteng]

When volume manager initializes a backend, one of the steps is to let backend driver to update provider info for list of volumes in Cinder DB. Current code assumed that every volume (no matter what status it is in) can be found in backend, which in some cases are not true. In those cases, Cinder volume service would fail to start due to a unhandled IndexError.

====================
    def _sync_provider_info(self, ctxt, volumes, snapshots):
         updates, snapshot_updates = self.driver.update_provider_info(
             volumes, snapshots)

         if updates:
             for volume in volumes:
                 # NOTE(JDG): Make sure returned item is in this hosts volumes
                 update = (
                     [updt for updt in updates if updt['id'] ==
                         volume['id']][0]) <--
                 if update:
                     self.db.volume_update(
                         ctxt,
                         update['id'],
                         {'provider_id': update['provider_id']})
----------------------

File "cinder/volume/manager.py", line 428, in init_host
        self._sync_provider_info(ctxt, volumes, snapshots)
      File "cinder/volume/manager.py", line 349, in _sync_provider_info
        volume['id']][0])
    IndexError: list index out of range

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/378175

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/378175
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=d96fb9a10135df062732279bac2d7eb6073872b0
Submitter: Jenkins
Branch: master

commit d96fb9a10135df062732279bac2d7eb6073872b0
Author: Zhiteng Huang <email address hidden>
Date: Tue Sep 27 19:31:59 2016 -0700

    Fix IndexError in volume manager

    A list comprehension in volume manager can raise IndexError due
    to unsafe assumption of input. This change fix it by not assuming
    list comprehension always return none empty list. This also fixes
    a snapshot DB call by using OVO.

    Change-Id: I83e8ac8dcf9e84b37847d6eb09065d55e843f82e
    Closes-bug: #1628340

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/newton
Review: https://review.openstack.org/379775

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/mitaka
Review: https://review.openstack.org/379776

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/379776
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=5b22d174d6feed70c92556af48546b22aec1e86d
Submitter: Jenkins
Branch: stable/mitaka

commit 5b22d174d6feed70c92556af48546b22aec1e86d
Author: Zhiteng Huang <email address hidden>
Date: Tue Sep 27 19:31:59 2016 -0700

    Fix IndexError in volume manager

    A list comprehension in volume manager can raise IndexError due
    to unsafe assumption of input. This change fix it by not assuming
    list comprehension always return none empty list. This also fixes
    a snapshot DB call by using OVO.

    Change-Id: I83e8ac8dcf9e84b37847d6eb09065d55e843f82e
    Closes-bug: #1628340
    (cherry picked from commit d96fb9a10135df062732279bac2d7eb6073872b0)

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/379775
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=6079b7b0b9098e96b903d39e5d27803c9c97a5a0
Submitter: Jenkins
Branch: stable/newton

commit 6079b7b0b9098e96b903d39e5d27803c9c97a5a0
Author: Zhiteng Huang <email address hidden>
Date: Tue Sep 27 19:31:59 2016 -0700

    Fix IndexError in volume manager

    A list comprehension in volume manager can raise IndexError due
    to unsafe assumption of input. This change fix it by not assuming
    list comprehension always return none empty list. This also fixes
    a snapshot DB call by using OVO.

    Change-Id: I83e8ac8dcf9e84b37847d6eb09065d55e843f82e
    Closes-bug: #1628340
    (cherry picked from commit d96fb9a10135df062732279bac2d7eb6073872b0)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 9.1.0 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 10.0.0.0b1 development milestone.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 9.1.0 release.