Fix deadlock possibility in federated informer #30872
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mwielgus
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| @@ -344,8 +344,6 @@ func (f *federatedInformerImpl) getReadyClusterUnlocked(name string) (*federatio | |||
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| // Synced returns true if the view is synced (for the first time) | |||
| func (f *federatedInformerImpl) ClustersSynced() bool { | |||
| f.Lock() | |||
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Why are you removing this one?
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Because clusterInformer is set only once in the "constructor". It is never modified. So there is no need for locking.
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One comment - other than that lgtm. |
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GCE e2e build/test passed for commit 681d153. |
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Automatic merge from submit-queue |
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On cluster add subinformer locks and tries to add cluster to federated informer. When someone checks if everything is in sync federated informer is locked and then subinformer is inspected what apparently requires a lock. With really bad timing this can create a deadlock.
This PR ensures that there is always at most 1 lock taken in federated informer.
cc: @quinton-hoole @kubernetes/sig-cluster-federation
Fixes: #30855
This change is