PM31430: DFHSO0001 AN ABEND (CODE 0C4/AKEA) HAS OCCURRED AT OFFSET X'0258' IN MODULE DFHSOXM DUE TO TCPIPSERVICE CLOSURE ISSUES.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You receive message DFHSO0001 An abend (code 0C4/AKEA)
  has occurred at offset X'0258' in module DFHSOXM.  This is
  accompanied with message DFHXM0306  A server error (code
  X'1345') has occurred while initializing task number nnnnn with
  transaction identifier CWXN. The task is suspended indefinitely.
  .
  This message tells us that a normal shutdown of CICS will not
  terminate this task.  You must CANCEL CICS.
  
  Transaction CWXN was attached by the listener task CSOL passing
  the STE in the primary client request block.
  Before CWXN first dispatch occurred, the TCPIPService where the
  request was received was either terminated IMMediate or
  terminated abnormally.  This caused all the SOCKETs and STEs
  chain of the LTE to be freemained.
  
  
  The CWXN task got dispatch (First Dispatch) about 17 minutes
  after the XMAT ATTACH.  DFHSOXM init client gets the STE from
  DFHXMTxn field xm_txn_primary_client_request_block_addr, which
  is no longer valid.
  This results in message DFHSO0001 and DFHXM0306.
  The SO domain in the dump shows that all the TCPIPServices did
  not have an LTE.
  Additional Symptom(s) Search Keyword(s):
  KIXREVSLY
  ABENDS0C4 ABEND0C4 MSGDFHSO0001 MSGDFHXM0306
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION: DFHSO0001 an abend (code 0C4/AKEA) has  *
  *                      occurred in module DFHSOXM following    *
  *                      IMMCLOSE of a TCPIPSERVICE.             *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  MSGDFHSO0001 occurs due to an ABEND0C4 in DFHSOXM function
  INIT_XM_CLIENT when a web receiver task ( CWXN ) starts
  running. This is followed by message DFHXM0306 - severe error
  code 1345.
  The CWXN task was attached a long time before this error and was
  delayed due to the system hitting the MAXTASK limit.
  Between the point where the CWXN task was attached and its
  initial dispatch, the TCPIPSERVICE which spawned the CWXN task
  was IMMCLOSED.
  IMMCLOSE processing closes and deletes all sockets and STE
  blocks associated with the TCPIPSERVICE. This included the STE
  which the CWXN task was referencing as its
  PRIMARY_CLIENT_REQUEST_BLOCK.
  The freed STE was subsequently getmained as non-STE storage and
  overwritten. When DFHSOXM INIT_XM_CLIENT eventually executed, it
  suffered an ABEND0C4 when it tried to use the freed STE to
  access a field within the socket object referenced by the STE.
  
  ADDITIONAL KEYWORDS :- ABENDS0C4 0C4 S0C4 SO0001 MSGDFHXM0306
                         XM0306
  

Problem conclusion

• DFHWBSO has been changed to pass the unique socket token
  associated with a web request to transaction manager when a web
  receiver task is attached.
  DFHSOXM has been changed to retrieve the unique socket token
  from transaction manager as part of INIT_XM_CLIENT. DFHSOXM
  validates that the retrieved token references a still active
  socket before attempting to reference its STE.
  If the socket token is no longer active, the web receiver task
  will abend ASOD.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  PM28637

• APAR is sysrouted TO one or more of the following:

  UK65328

Modules/Macros

•    DESSOXM  DESWBSO  DFHSOXM  DFHWBSO
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R600 PSY UK65328

     UP11/03/08 P F103

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.