rbd: "error updating features for image" when enabling multi-attach

[Mikolaj Golub]

In the rbd driver, when enabling multiattach it tries to disable some rbd image features (which are in MULTIATTACH_EXCLUSIONS list) [1]. If the image does not have any of these features (like in the case when it was created with rbd_default_features = 3), it still tries to call "update_features" librbd function with "changed_features = 0". And the librbd does not like this, considering this as invalid [2].

As a result it fails with an error like below:

  [errno 22] RBD invalid argument (error updating features for image b'volume-f664bb1c-7217-4c5a-8867-b36766afcde6')

The fix could be just to skip calling librbd's `update_feature` if there is nothing to update ("changed_features" is 0). (And the same should be done in _disable_multiattach).

[1] https://github.com/openstack/cinder/blob/24f43918eacad6db89d613d11f9cd7f796208e9c/cinder/volume/drivers/rbd.py#L952
[2] https://github.com/ceph/ceph/blob/2a9fac2cc4b10af04c52e12f34932e6d2d91441f/src/librbd/Operations.cc#L1503

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/cinder/+/865855

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/cinder/+/865855
Committed: https://opendev.org/openstack/cinder/commit/6e08f15074baa608d238959aa8f3fd6c9838ad7d
Submitter: "Zuul (22348)"
Branch: master

commit 6e08f15074baa608d238959aa8f3fd6c9838ad7d
Author: Eric Harney <email address hidden>
Date: Mon Nov 28 09:26:18 2022 -0500

    RBD: Skip update_features when features = 0

    librbd errors when update_features is called w/
    features = 0 -- when this situation would occur,
    skip calling update_features.

    Closes-Bug: #1997980
    Change-Id: Iab6a990ce7dee2c13deb4f46aeec0f46ffb7cd62

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/2023.1
Review: https://review.opendev.org/c/openstack/cinder/+/881435

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/cinder/+/881435
Committed: https://opendev.org/openstack/cinder/commit/efd74240978cbbe10f547cc188a9a461c0fb5b5d
Submitter: "Zuul (22348)"
Branch: stable/2023.1

commit efd74240978cbbe10f547cc188a9a461c0fb5b5d
Author: Eric Harney <email address hidden>
Date: Mon Nov 28 09:26:18 2022 -0500

    RBD: Skip update_features when features = 0

    librbd errors when update_features is called w/
    features = 0 -- when this situation would occur,
    skip calling update_features.

    Closes-Bug: #1997980
    Change-Id: Iab6a990ce7dee2c13deb4f46aeec0f46ffb7cd62
    (cherry picked from commit 6e08f15074baa608d238959aa8f3fd6c9838ad7d)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 22.1.1 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 23.0.0.0rc1 release candidate.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/zed
Review: https://review.opendev.org/c/openstack/cinder/+/908690