IZ67935: SYSTEM CRASH IN VNOP_HOLD WHEN USING CACHEFS APPLIES TO AIX 6100-06

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• System crash when using cachefs with the following stack
  trace:
  
  (2)> f
  pvthread+80F200 STACK:
  [004E6620]bad_vnode_bad_caller+000000 (F10001102D8B3080
  [??])
  [004ED57C]vnop_hold+00011C (??)
  [050DAAB8]dnlc_lookup+0002B8 (??, ??, ??)
  [050C2068]cachefs_lookup+0001C8 (??, ??, ??, ??, ??, ??,
  ??)
  [0509DAA0]aix2onc_lookup+000080 (??, ??, ??, ??, ??, ??)
  [004ECA08]vnop_lookup+000188 (??, ??, ??, ??, ??, ??)
  [00498FA0]lookuppn+0008E0 (??, ??, ??, ??, ??, ??, ??,
  ??)
  [0053E298]openpnp+0008B8 (??, ??, ??, ??, ??, ??)
  [0053E420]openpath+000100 (??, ??, ??, ??, ??, ??, ??)
  [0053E89C]copen+00023C (??, ??, ??, ??, ??)
  [0053D95C]kopen+00001C (??, ??, ??)
  [00003844].svc_instr+000144 ()
  
  The problem happens only when applications use the mmap()
  and munmap()
  routines for files on over cachefs.
  

Local fix

• Mount filesystems directly using NFS instead of cachefs
  

Problem summary

• System crash when using cachefs with the following stack
  trace:
  
  (2)> f
  pvthread+80F200 STACK:
   004E6620 bad_vnode_bad_caller+000000 (F10001102D8B3080
   ?? )
   004ED57C vnop_hold+00011C (??)
   050DAAB8 dnlc_lookup+0002B8 (??, ??, ??)
   050C2068 cachefs_lookup+0001C8 (??, ??, ??, ??, ??, ??,
  ??)
   0509DAA0 aix2onc_lookup+000080 (??, ??, ??, ??, ??, ??)
   004ECA08 vnop_lookup+000188 (??, ??, ??, ??, ??, ??)
   00498FA0 lookuppn+0008E0 (??, ??, ??, ??, ??, ??, ??,
  ??)
   0053E298 openpnp+0008B8 (??, ??, ??, ??, ??, ??)
   0053E420 openpath+000100 (??, ??, ??, ??, ??, ??, ??)
   0053E89C copen+00023C (??, ??, ??, ??, ??)
   0053D95C kopen+00001C (??, ??, ??)
   00003844 .svc_instr+000144 ()
  
  The problem happens only when applications use the mmap()
  and munmap() routines for files on over cachefs.
  

Problem conclusion

• Modified cachefs code to return proper error number.
  

Temporary fix

Comments

• 5300-08 - use AIX APAR IZ73845
  5300-09 - use AIX APAR IZ73785
  5300-10 - use AIX APAR IZ73715
  5300-11 - use AIX APAR IZ67901
  5300-12 - use AIX APAR IZ67823
  6100-01 - use AIX APAR IZ75429
  6100-02 - use AIX APAR IZ59271
  6100-03 - use AIX APAR IZ75377
  6100-04 - use AIX APAR IZ68054
  6100-05 - use AIX APAR IZ67797
  6100-06 - use AIX APAR IZ67935
  7100-00 - use AIX APAR IZ81785
  

APAR Information

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

  IZ59271

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

Fix information

• Fixed component name

  AIX 610

• Fixed component ID

  5765G6200

Applicable component levels

• R610 PSY U838864

     UP10/09/03 I 1000