Add poststarthook to wait for SV informer to sync

staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/apiserver.go

@@ -149,6 +149,7 @@ func (c completedConfig) New(delegationTarget genericapiserver.DelegationTarget)
 	// hasCRDInformerSyncedSignal is closed when the CRD informer this server uses has been fully synchronized.
 	// It ensures that requests to potential custom resource endpoints while the server hasn't installed all known HTTP paths get a 503 error instead of a 404
 	hasCRDInformerSyncedSignal := make(chan struct{})
+	hasSVInformerSyncedSignal := make(chan struct{})
 	if err := genericServer.RegisterMuxAndDiscoveryCompleteSignal("CRDInformerHasNotSynced", hasCRDInformerSyncedSignal); err != nil {
 		return nil, err
 	}
@@ -313,6 +314,19 @@ func (c completedConfig) New(delegationTarget genericapiserver.DelegationTarget)
 		}, context.StopCh)
 	})
 
+	if utilfeature.DefaultFeatureGate.Enabled(features.StorageVersionAPI) &&
+		utilfeature.DefaultFeatureGate.Enabled(features.APIServerIdentity) {
+		s.GenericAPIServer.AddPostStartHookOrDie("sv-informer-synced", func(context genericapiserver.PostStartHookContext) error {
+			return wait.PollImmediateUntil(100*time.Millisecond, func() (bool, error) {
+				if s.StorageVersionInformers.Internal().V1alpha1().StorageVersions().Informer().HasSynced() {
+					close(hasSVInformerSyncedSignal)
+					return true, nil
+				}
+				return false, nil
+			}, context.StopCh)
+		})
+	}
+
 	return s, nil
 }
 

test/integration/controlplane/transformation/kms_transformation_test.go

@@ -615,11 +615,11 @@ resources:
     - kms:
         name: encrypt-all-kms-provider
         cachesize: 1000
-        endpoint: unix:///@encrypt-all-kms-provider.sock
+        endpoint: unix:///@encrypt-all-kms-provider.sock-100
 `
 
 	t.Run("encrypt all resources", func(t *testing.T) {
-		_ = mock.NewBase64Plugin(t, "@encrypt-all-kms-provider.sock")
+		_ = mock.NewBase64Plugin(t, "@encrypt-all-kms-provider.sock-100")
 		// To ensure we are checking all REST resources
 		defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, "AllAlpha", true)()
 		defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, "AllBeta", true)()