APAR status
Closed as program error.
Error description
When the client or channel connection end, the following failure data capture (FDC) record may be generated: Operating System :- Linux 3.10.0-1062.18.1.el7.x86_64 LVLS :- 9.0.0.10 Probe Id :- XC006001 Component :- xcsFreeMemFn Program Name :- amqrmppa Major Errorcode :- xecS_I_PRIVATE_MEMORY_ERROR Minor Errorcode :- OK Probe Type :- MSGAMQ6091 Probe Description :- AMQ6091: An internal IBM MQ error has occurred Arith1 :- 47352551930080 (0x2b11200978e0) Comment1 :- invalid head tag MQM Function Stack ccxResponder rrxResponder ccxReceiveThreadFn ccxReceiveThreadCleanup cciEndConv rriAsyncConvControl rriFreeSess ccxStageFree xcsFreeMemFn xcsFFST The FDC's indicates that the memory being freed has already been freed. The UseCount has dropped to 0 so this is why it is freed, but the code is not recording this fact fully and once again attempts to free it in the ccxStageFree after the conversation it cleared.
Local fix
Changing the SHARECNV value to 0 may help.
Problem summary
**************************************************************** USERS AFFECTED: MQ Client or Channel applications with SHARECONV >= 1 Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: When a client or channel conversation ends, the receive pool header buffer was freed and a pointer to the unassigned buffer location was not cleared. Later, an attempt was made to free the pool header buffer a second time using the stale pointer, leading to the FDC indicating an invalid buffer corruption.
Problem conclusion
The stale pointer is now cleared when the buffer is freed. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v9.0 LTS 9.0.0.12 v9.1 LTS 9.1.0.9 v9.2 LTS 9.2.0.2 v9.x CD 9.2.3 The latest available maintenance can be obtained from 'WebSphere MQ Recommended Fixes' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037 If the maintenance level is not yet available information on its planned availability can be found in 'WebSphere MQ Planned Maintenance Release Dates' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309 ---------------------------------------------------------------
Temporary fix
Comments
APAR Information
APAR number
IT34004
Reported component name
IBM MQ BASE M/P
Reported component ID
5724H7261
Reported release
900
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2020-08-25
Closed date
2021-03-24
Last modified date
2022-04-14
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
IBM MQ BASE M/P
Fixed component ID
5724H7261
Applicable component levels
[{"Line of Business":{"code":"LOB45","label":"Automation"},"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.0"}]
Document Information
Modified date:
15 April 2022