PI56874: DFHIS0001 ABEND AKEC RUNAWAY DETECTED IN MODULE DFHISZA TRYING TO TRACE THE OUTPUT BUFFER FROM DPL REQUEST

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You are running CICS Transaction server 5.1, and have an
  IPIC connection to the CTG.  A distributed programming link or
  DPL request comes in through this IPIC connection from the CTG.
  The request gets routed to the AOR and appears to complete
  normally there, but in the TOR you receive:
  .
  DFHIS0001 An abend (code ---/AKEC) has occurred at
            offset X'FFFF' in module DFHISZA.
  .
  The AKEC indicates the kernel (KE) domain has detected runaway.
  Reviewing the dump at the time of this abend we find there is a
  tight loop in module DFHISZA, trying to trace an output buffer.
  CICS internal trace shows the following trace entry over and
  over, with no additional data under it:
  .
  IS 0906 ISZA  DATA  UNFORMATTED_BUFFER
  .
  DFHISZA is trying to move through the data buffer and mistakenly
  looks at application data for IS Field data causing it to
  get a length of '0'.  This causes the loop because DFHISZA
  bumps by 0 each time, which doesn't change anything, so it
  never gets to the end of the data, which would stop the loop.
  This is another variant to the problem fixed by PI32442.
  
  Additional Symptom(s) Search Keyword(s): KIXREVRJL
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS Users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: DFHIS0001 An abend (code ---/AKEC) has  *
  *                      occurred at offset X'FFFF' in module    *
  *                      DFHISZA.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A CICS client sends a DPL request over IPIC to a CICS server
  with a large container. After the CICS server processes the
  request it sends a response to the CICS client also with a large
  container, DFHISZA is invoked to send the container data in a
  buffer to the CICS client. As the container data is very large,
  more than 1 buffer is used to send the IS field for the
  container data. The buffers are in a chain. When DFHISZA tries
  to write a trace entry for the buffer it wrongly treats the
  buffer data as a new IS field. As a result, it wrongly
  calculates the length of the IS field as being 0. This results
  in a loop, as DFHISZA never reaches the end of the data and the
  abend AKEC is issued.
  

Problem conclusion

• DFHISZA has been changed to interpret the data correctly.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

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

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

  PI62598 UI38583 UI38584

Modules/Macros

• DFHISZA
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R800 PSY UI38583

     UP16/06/17 P F606

• R900 PSY UI38584

     UP16/06/17 P F606

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.