PM50939: DFHSM0002 A SEVERE ERROR (CODE X'0305') HAS OCCURRED IN MODULE DFHSMGF

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You are running CICS TS 4.1, and running tasks that utilize
  a TCPIPService.  You encounter message DFHSM0002, "A severe
  error (code X'0305') has occurred in module DFHSMGF "
  .
  In the trace, you find the entry:
  SL  SM 0305 SMGF  *EXC* Invalid_freemain_address FREEMAIN,
  SUBPOOL_TOKEN(320BE674 , 000000CE) ADDRESS(33B3A000)
  REMARK(LTE)
  .
  Looking back thru the trace entries prior to the error, you
  may discover 2 nearly consecutive FREEMAINs for an identical
  LTE address.
  .
  KIXREVxxx
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Message 'DFHSM0002 A severe error       *
  *                      (code X'0305') has occurred in          *
  *                      module DFHSMGF' is issued when          *
  *                      installing a TCPIPSERVICE.              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A user task is opening a TCPIPSERVICE.  This causes DFHSORD
  to create a new LTE, add it to the LTE chain, post the
  listener task to process it and then wait on an ecb for the
  listener task to finish.
  The listener task CSOL wakes up and finds it has a register
  to perform. It locates the newly created LTE, creates a
  socket and then issues a bind call, but this call fails.
  CSOL begins its error processing, posting the ecb with a bad
  completion code indicating that the register failed.
  This now allows the user task to wake up and run on the QR TCB
  while CSOL continues processing on SL.
  CSOL obtains the SO domain lock exclusive, then removes the
  LTE from the chain. In parallel the user task is running.
  It finds that the register call failed and freemains the LTE.
  It does not attempt to get the SO domain lock before doing
  this.
  On the SL TCB, CSOL also attempts to freemain the LTE, however
  this call fails resulting in msgDFHSM0002 and an SDUMP.
  

Problem conclusion

• DFHSORD has been changed to acquire the SO domain lock before
  attempting to freemain the LTE.
  

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:

  UK74334 UK74335

Modules/Macros

• DESSORD  DFHSORD
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R600 PSY UK74334

     UP11/12/09 P F112

• R700 PSY UK74335

     UP11/12/09 P F112

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.