PQ87507: TCPIP APPEAR TO BE HUNG WHILE CSM WAS CONSTRAINED

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Customer experience a hung condition in TCPIP while CSM was
  constrained.  EZBTCRDG issued an unconditional csm storage
  request while holding the TCB lock.  Since the storage was not
  available, the task went into a wait while holding the TCB lock.
  ADDITIONAL SYMPTOMS:
  The customer could experience the hang during the force arm
  since the STREAMACCESS lock is waiting for the TCB lock to be
  freed.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for OS/390 Release 10 IP, for z/OS Version 1 *
  *                 Release 2, 4, 5 and 6 IP                     *
  ****************************************************************
  * PROBLEM DESCRIPTION: TCP/IP stack appears to be hung while   *
  *                      CSM storage shortage exists and         *
  *                      termination is requested                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  While trying to terminate the TCP/IP stack, it appeared to be
  hung due to lack of CSM storage. The stack was trying to create
  a RST package and was not able to obtain the storage to do this.
  The storage request was unconditional so the stack would wait
  forever and could not continue the termination process.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

• Code in the routine BldReset() was changed to do a conditional
  storage obtain for the RST package. If storage could not be
  gotten, the TCP/IP stack continues processing. This would allow
  termination of the stack to proceed.
  
  * Cross Reference between External and Internal Names
  

Temporary fix

Comments

APAR Information

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

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

  UQ88072 UQ88071 UQ88073 UQ88074 UQ88075

Modules/Macros

• EZBTCRDG
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R120 PSY UQ88071

     UP04/05/27 P F405

• R140 PSY UQ88072

     UP04/05/27 P F405

• R150 PSY UQ88073

     UP04/05/27 P F405

• R160 PSY UQ88074

     UP04/06/01 P F405

• R50A PSY UQ88075

     UP04/06/01 P F405

Fix is available

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