title: Data unpack would read past end of buffer in file util/show_help.c at line 501
body: <p>I submitted a job via slurm. The job ran for 12 hours and was working as expected. Then I got <code>Data unpack would read past end of buffer in file util/show_help.c at line 501</code>. It is usual for me to get errors like <code>ORTE has lost communication with a remote daemon</code> but I usually get this in the beginning of the job. It is annoying but still does not cause as much time loss as getting error after 12 hours. Is there a quick fix for this? Open MPI version is 4.0.1.</p>
  <pre><code>--------------------------------------------------------------------------                                                                                                                                                                       
  By default, for Open MPI 4.0 and later, infiniband ports on a device                                                                                                                                                                         
  are not used by default.  The intent is to use UCX for these devices.                                                                                                                                                                        
  You can override this policy by setting the btl_openib_allow_ib MCA parameter                                                                                                                                                                    
  to true.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
  Local host:              barbun40                                                                                                                                                                                                            
  Local adapter:           mlx5_0                                                                                                                                                                                                              
  Local port:              1                                                                                                                                                                                                                                                                                                                                                                                                                                                              
  --------------------------------------------------------------------------                                                                                                                                                                   
  --------------------------------------------------------------------------                                                                                                                                                                   
  WARNING: There was an error initializing an OpenFabrics device.                                                                                                                                                                                                                                                                                                                                                                                                                             
  Local host:   barbun40                                                                                                                                                                                                                       
  Local device: mlx5_0                                                                                                                                                                                                                       
  --------------------------------------------------------------------------                                                                                                                                                                   
  [barbun21.yonetim:48390] [[15284,0],0] ORTE_ERROR_LOG: Data unpack would read past end of buffer in 
  file util/show_help.c at line 501                                                                                                        
  [barbun21.yonetim:48390] 127 more processes have sent help message help-mpi-btl-openib.txt / ib port 
  not selected                                                                                                                            
  [barbun21.yonetim:48390] Set MCA parameter &quot;orte_base_help_aggregate&quot; to 0 to see all help / error 
  messages                                                                                                                                  
  [barbun21.yonetim:48390] 126 more processes have sent help message help-mpi-btl-openib.txt / error in 
  device init                                                                                                                            
  --------------------------------------------------------------------------                                                                                                                                                                   
  Primary job  terminated normally, but 1 process returned                                                                                                                                                                                     
  a non-zero exit code. Per user-direction, the job has been aborted.                                                                                                                                                                          
  --------------------------------------------------------------------------                                                                                                                                                                   
  --------------------------------------------------------------------------                                                                                                                                                                   
  An MPI communication peer process has unexpectedly disconnected.  This                                                                                                                                                                       
  usually indicates a failure in the peer process (e.g., a crash or                                                                                                                                                                            
  otherwise exiting without calling MPI_FINALIZE first).                                                                                                                                                                                                                                                                                                                                                                                                                                    
  Although this local MPI process will likely now behave unpredictably                                                                                                                                                                         
  (it may even hang or crash), the root cause of this problem is the                                                                                                                                                                           
  failure of the peer -- that is what you need to investigate.  For                                                                                                                                                                            
  example, there may be a core file that you can examine.  More                                                                                                                                                                                
  generally: such peer hangups are frequently caused by application bugs                                                                                                                                                                       
  or other external events.                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
  Local host: barbun64                                                                                                                                                                                                                         
  Local PID:  252415                                                                                                                                                                                                                           
  Peer host:  barbun39                                                                                                                                                                                                                       
  --------------------------------------------------------------------------                                                                                                                                                                   
  --------------------------------------------------------------------------                                                                                                                                                                   
  mpirun detected that one or more processes exited with non-zero status, thus causing                                                                                                                                                         
  the job to be terminated. The first process to do so was:                                                                                                                                                                                                                                                                                                                                                                                                                                   
  Process name: [[15284,1],35]                                                                                                                                                                                                                 
  Exit code:    9                                                                                                                                                                                                                            
  --------------------------------------------------------------------------  
  </code></pre>