IJ20863: SIGBUS DURING MMAP WRITE TO A COMPRESSED FILE

APAR status

• Closed as program error.

Error description

• When writing to a memory mapped file that was compressed, it
  fails with SIGBUS
  
  when mmapRangeLock config variable is disabled.
  

Local fix

•           Don't disable mmapRangeLock config variable
  

Problem summary

•  When writing to a memory mapped file that was compressed, it
  fails with SIGBUS
  
  when mmapRangeLock config variable is disabled.
  

Problem conclusion

• Benefits of the solution: With the fix, customer doesn't see
  this failure.
   Work around: Don't disable mmapRangeLock config variable
  
  Problem trigger:
  
  Writing to memory mapped files that were compressed, and
  mampRangeLock config
  
  variable is disabled.
  
  Symptom:
  
  Application fails with SIGBUS
  
  Platforms affected:
  
  ALL Linux OS environments
  
  Functional Area affected:
  
  All Scale Users
  
  Customer Impact: It is critical if customer disabled
  mmapRangeLock config
  
  variable and running the release that has defect 1090269.
  Normally customers
  
  do not run with mmapRangeLock config variable disabled since it
  is always
  
   enabled by default and customer should not disable unless
  suggested by IBM service.
  

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:

Fix information

• Fixed component name

  GPFS NR POWER E

• Fixed component ID

  5725Q01NP

Applicable component levels