PM97250: CICS HANGS WITH LMQUEUE SUSPENDS FOR DSITLOCK

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• CICS region hangs with most tasks suspended for resource
  LMQUEUE or ENQUEUE EXECSTRN. The problem is that the owner of
  the DSITLOCK is hung. Dispatcher/Kernel domains show that the
  DSITLOCK owner is running on the SP TCB. However, the SP TCB is
  currently in an SVC1 Wait issued out of DFHLEPT (offset
  x'5A2'), waiting on ECB, KIPT_READY_ECB. Kernel stacks show
  that the task dispatched on the SP TCB is processing a
  CREATE_PTHREAD call. DFHLEPT has posted the KIPT_WAKEUP_ECB to
  wake up the IPT TCB. However, there is no IPT TCB formatted in
  SUMM FORMAT (should show associated program DFHKEATT).
  .
  The problem appears to have occurred after an unknown signal
  woke up the IPT TCB and caused it to terminate unexpectedly
  while SSL requests are still in progress on S8 TCBs.
  .
  Additional Symptom(s) Search Keyword(s):
  KIXREVSLY  SSL or LE enclave terminates.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: CICS hangs when the LE enclave used     *
  *                      for SSL processing is terminated        *
  *                      unexpectedly for a USS signal.          *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A CICS region is running with SSL active. A USS signal is sent
  to the process that is the SSL/LE enclave inside CICS, then the
  LE enclave is terminated.
  When the next task to make an SSL request is received, a new S8
  TCB needs to be created. The task switches to the SP TCB and
  tries to create a pthread. This posts the IPT and then waits for
  the IPT to complete the creation of the pthread.
  As the LE enclave has been terminated, this never happens so the
  task on the SP TCB waits forever, holding the DSITLOCK.
  All further tasks requiring S8 TCBs will wait behind this task.
  Then CICS hangs.
  

Problem conclusion

• DFHLEPT has been changed to block all possible signals into the
  process that is the SSL/LE enclave inside CICS.
  

Temporary fix

•             *********
              * HIPER *
              *********
  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:

  PI05213 UI12848 UI12849

Modules/Macros

•    DFHLEPT  DFHLEPT@ DFHLEPTD DFHLEPTI
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R700 PSY UI12848

     UP13/11/30 P F311

• R703 PSY UI12849

     UP13/11/30 P F311

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.