diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index a1ce5d8b8a236635aade72885b568bc6056e5241..905502f145b24928167b41ee7b5485fc972a5b86 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -3675,6 +3675,8 @@ VirtualXactLock(VirtualTransactionId vxid, bool wait)
 	 * it's no longer running anywhere.
 	 */
 	proc = BackendIdGetProc(vxid.backendId);
+	if (proc == NULL)
+		return true;
 
 	/*
 	 * We must acquire this lock before checking the backendId and lxid