VM65689: HTT001 ABEND VARY OFF CHPIDS AND MONITOR ENABLED

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• ABENDHTT001 can occur when CHPIDS are varied off and Monitor
  is enabled.
  
  Monitor chains through CUIBKs, Control Unit Information Blocks,
  to collect information about current I/O Devices.  If a device
  is varied offline as Monitor is chaining through these control
  blocks it is possible the storage for the CUIBK has been
  released which results in an HTT001 ABEND.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of z/VM who vary off CHPIDs with   *
  *                 Monitor enabled.                             *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  ****************************************************************
  * RECOMMENDATION: APPLY PTF                                    *
  ****************************************************************
  ABENDHTT001 can occur when CHPIDS are varied off and CP
  Monitor is enabled.
  
  Monitor chains through CUIBKs, Control Unit Information Blocks,
  to collect information about current I/O Devices.  If a device
  is varied offline as Monitor is chaining through these control
  blocks it is possible the storage for the CUIBK has been
  released which results in an HTT001 ABEND.
  

Problem conclusion

• The Monitor parts, HCPMOM and HCPMNO, are updated to get the
  SYSCUILK lock prior to scanning the CUIBK tree. This will
  prevent a member in the tree from being deleted while Monitor is
  scanning the tree avoiding the abend. Once monitor is done
  processing the lock is released.
  

Temporary fix

• *********
  * HIPER *
  *********
  FOR RELEASE VM/ESA CP/ESA R640 :
  PREREQ: NONE
  CO-REQ: NONE
  IF-REQ: NONE
  FOR RELEASE VM/ESACP/ESAR710 :
  PREREQ: NONE
  CO-REQ: NONE
  IF-REQ: NONE
  

Comments

APAR Information

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

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

  UM35432 UM35433

Modules/Macros

• HCPMNO   HCPMOM
  

Fix information

• Fixed component name

  VM CP

• Fixed component ID

  568411202

Applicable component levels

• R640 PSY UM35432

     UP19/08/05 P 2001 ¢

• R710 PSY UM35433

     UP19/08/05 P 1902 ¢

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.