This PR tries to fix issue #29324. This cause of this issue is a race
condition happens when marking volumes as attached for node status. This
PR tries to clean up the logic of when and where to mark volumes as
attached/detached. Basically the workflow as follows,
1. When volume is attached sucessfully, the volume and node info is
added into nodesToUpdateStatusFor to mark the volume as attached to the
node.
2. When detach request comes in, it will check whether it is safe to
detach now. If the check passes, remove the volume from volumesToReportAsAttached
to indicate the volume is no longer considered as attached now.
Afterwards, reconciler tries to update node status and trigger detach
operation. If any of these operation fails, the volume is added back to
the volumesToReportAsAttached list showing that it is still attached.
These steps should make sure that kubelet get the right (might be
outdated) information about which volume is attached or not. It also
garantees that if detach operation is pending, kubelet should not
trigger any mount operations.
This PR is to add event message when attaching volume fails to help
users to debug. For detach failure, may address in a different PR since
it requires more data structure change.
For non-attachable volumes, do not call GetVolumeName on the plugin and instead
generate a unique name based on the identity of the pod and the name of the volume
within the pod.
