Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

Kill TiDB when the owner just cleans tidb_mdl_info while not cleaning the etcd info.

If so, that DDL is blocked.

2. What did you expect to see? (Required)

DDL finish finally.

3. What did you see instead (Required)

DDL get blocked

4. What is your TiDB version? (Required)

6.5 7.1 master