MySQL 已经设置了 skip-name-resolve，但还会出现 unauthenticated user 信息

Question

MySQL 已经设置了 skip-name-resolve，但还会出现 unauthenticated user 信息，是什么原因 ？

mysql> show full processlist;
+-----+----------------------+--------------------+------+---------+------+----------------------------------+-----------------------+
| Id  | User                 | Host               | db   | Command | Time | State                            | Info                  |
+-----+----------------------+--------------------+------+---------+------+----------------------------------+-----------------------+
|   1 | system user          |                    | NULL | Connect |  623 | Waiting for master to send event | NULL                  | 
|   2 | system user          |                    | NULL | Connect |    0 | Reading event from the relay log | NULL                  | 
| 585 | root                 | localhost          | dd   | Query   |    0 | NULL                             | show full processlist | 
| 748 | unauthenticated user | 2.191.10.27:32833  | NULL | Connect | NULL | login                            | NULL                  | 
| 749 | unauthenticated user | 2.191.10.27:32836  | NULL | Connect | NULL | login                            | NULL                  | 
……
| 799 | unauthenticated user | 2.191.10.139:46877 | NULL | Connect | NULL | login                            | NULL                  | 
| 800 | unauthenticated user | 2.191.10.139:46879 | NULL | Connect | NULL | login                            | NULL                  | 
+-----+----------------------+--------------------+------+---------+------+----------------------------------+-----------------------+
556 rows in set (0.00 sec)