PM69241: ABENDSB78 RC 00000018 WHEN DOING A STORAGE RELEASE FROM DFSAOSW0FOR AN AWE.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Abend SB78 - 00000018 is issued indicating the wrong TCB has
  been passed on a Storage Release request. The Storage is being
  released by module DFSAOSW0. When the call is made DFSAOSW0
  passes the value found in AWAOSKEY. This AWE storage was
  obtained and queued by DFSXCF00. The storage was not cleared
  and key was not passed so the data used is residual. With the
  useage of the residual data it can result in the store of the
  key value to indicate in R15 that the TCB is being passed. If
  this happens, the abend will occur as no TCB is passed.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All IMS V12 users of APPC SMQ Enablement.    *
  ****************************************************************
  * PROBLEM DESCRIPTION: IMS control region abends with B78 RC18 *
  *                      'incorrect task control block ( TCB )   *
  *                      address' during a storage release       *
  *                      attempt.                                *
  ****************************************************************
  * RECOMMENDATION: INSTALL CORRECTIVE SERVICE FOR APAR/PTF      *
  ****************************************************************
  In an APPC shared queues environment with front-end and back-end
  IMS systems configuration, an IMS's XCF Message exit receives
  control when a message becomes available for this IMS.  The
  message was sent from another IMS member of the XCF group.  The
  message that the exit retrieves in this problem is DFS2224I
  'Transaction on a back-end system abended'.
  
  The exit obtains a storage buffer to hold the message data and
  then sends the buffer to a server for further processing.  When
  the server finishes its processing, it is responsible for
  releasing the obtained storage.  The exit sends the information
  about the storage such as subpool number, storage size to the
  server for releasing the storage, but does not send the storage
  key.  The server receives the storage information and uses the
  residual data as the storage key to release the storage.  The
  residual data can cause unpredictable results.
  
  The residual data was caused by an error in DFS6LUS0 which was
  not clearing the entire AWE after is was obtained.
  
  In this reported problem, the invalid storage key incorrectly
  turns on the 'TCBADDR provided' bit 5 of the byte 0 as an input
  to the storage release service.  The incorrectly-set flag causes
  the storage release service to expect the address of a TCB that
  owns the storage to be passed to it.  The TCB address is not, in
  fact, provided.  As a result, the release service fails with
  system abend B78 RC18 'incorrect task control block address' and
  this abend brings down the control region.
  
  IEA705I ERROR DURING FREEMAIN SYS CODE = B78-18 IMS1
  IEA705I 00FA7880 00693C58 00000000 0000010F
  DFS629I IMS RRS TCB ABEND - SYS B78           IMS1
  DFS629I PSW AT ERROR = 070C1000 8155FDF6  IMS1
  DFS629I MODID = UNKNOWN           EPA = UNKNOWN   IMS1
  DFS629I R0-3   84000000 84B78000 00000004 0F800001  IMS1
  DFS629I R4-7   00000000 00000005 00000007 00000B78  IMS1
  DFS629I R8-11  00000018 00004008 0C862FF8 00000000  IMS1
  DFS629I R12-15 8155FDBE 7FF14008 8C2D73FC 00000018  IMS1
  
  Additional Symptom: This failure in DFS6LUS0
  can also result in an 0c4 abend on the FE IMS
  in DFSAOSW0 at offset x'5BBA'. This is caused
  by AOSHEAD portion of the AWE having residual
  data indicating AOS_FPMSG.
  
  Note:  This APAR is not fully effective until it is installed on
  all IMSs in the shared queues group.  However, it does not need
  to be installed on all IMSs simultaneously.  It can be applied
  to one IMS system at a time in a rolling fashion until it has
  been installed on all IMSs in the shared queues group.
  
  KEYWORDS: ABENDSB78 RC18 SB78 B78 ABENDB78
  

Problem conclusion

• GEN:
  KEYWORDS:
   SYSPLEXSQ
  
  *** END IMS KEYWORDS ***
  DFSXCF00 - IMS Interface Module to z/OS XCF Services
  
  In the Message Exit XCFMSGE, added the storage key together with
  other storage information in the AWE to be sent to the message
  processing server.
  
  DFS6LUS0 - IMS LUM SERVICES
  
  Clear the entire AWE storage after it's obtained to remove any
  residual data. Then build the AWE information and send it to
  the front-end IMS via XCF for processing.
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

  PM69232

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

  UK80979

Modules/Macros

•    DFSXCF00 DFS6LUS0
  

Fix information

• Fixed component name

  IMS V12

• Fixed component ID

  5635A0300

Applicable component levels

• R200 PSY UK80979

     UP12/08/14 P F208 Ž

Fix is available

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