IJ44867: KERNEL LOCKUP IN LINUX __D_LOOKUP

APAR status

• Closed as program error.

Error description

• Kernel lockup due to dentries being added to lookup cache
  before complete initialization
  

Local fix

• Disabling deferred negative dentry invalidation with mmchconfig
  deferNegativeDcacheInvalidation=0 --force
  

Problem summary

• Kernel lockup due to dentries being added to lookup cache
  before complete initialization
  

Problem conclusion

• This problem is fixed in 5.1.6.1
  To see all Spectrum Scale APARs and their respective
  Fix solutions refer to page:
  https://public.dhe.ibm.com/storage/spectrumscale/spectrum_scale_
  apars.html
  
  Benefits of the solution:
  Introduce code to update dentry before introducing the
  dentry to the lookup cache
  
  Work Around:
  Disabling deferred negative dentry invalidation with mmchconfig
  deferNegativeDcacheInvalidation=0 --force
  
  Problem trigger:
  In order for the race condition to occur, multiple threads
  must be looking up the same file which does not exist,
  although this scenario does not guarantee that it will be
  reproduced.
  
  Symptom:
  Kernel deadlock
  
  Platforms affected:
  Linux Only
  
  Functional Area affected:
  All Scale users
  
  Customer Impact:
  High Importance
  

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

  SPEC SCALE STD

• Fixed component ID

  5737F33AP

Applicable component levels