delete(recreate) the dbconsole and repository of OEM

maybe you would get a momnet of failure of OEM when upgrade the rdbms,work as below to retry it

recreate OEM(OEM recreation will be done at the end of upgrade)

delete the dbconsole and repository of OEM
/u01/app/oracle/product/10.2.0/db_1/bin>emca -deconfig dbcontrol db -repos drop

recreate the dbcontrol and repository of OEM
/u01/app/oracle/admin/anqing/bdump>emca -config dbcontrol db -repos create