select count(*) into :b0 from USERCONFIRMINFO where USER_ID=:b1
The following deadlock is not an ORACLE error. It is a
deadlock due to user error in the design of an application
or from issuing incorrect ad-hoc SQL. The following
information may aid in determining the deadlock:

Deadlock graph:
---------Blocker(s)-------- ---------Waiter(s)---------
Resource Name process session holds waits process session holds waits
TX-000e005d-00037cfa 306 484 X 306 484 S
session 484: DID 0001-0165-00010802 session 484: DID 0001-0165-00010802
Rows waited on:
Session 484: no row
===================================================
I ever saw message talking about two session deadlock with no rows waited on, maybe it is because of pctfree/initrans, How about session wait on itself then?