IV01772: CRASH WHILE PROMOTING TO UNSHARED 1TB ALIASES IN V_SLB_CLR_1TB()APPLIES TO AIX 7100-01

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• System Crash with following stack trace:
  
  (5)> f
  pvthread+01EE00 STACK:
  [00022080]abend_trap+000000 ()
  [00035BC4]v_slb_clr_1tb+000164 (??)
  [00035DF8]v_stab_clr_range+000178 (??, ??)
  [0002DAF8]as_make_unsh_alias_st+000038 (??, ??, ??, ??)
  [0002DFC0]as_makealias+000280 (??, ??, ??, ??, ??, ??)
  [00033D5C]as_create_alias+0000DC (??, ??, ??, ??, ??, ??,
  ??)
  [005CA6B0]vm_lsa_promote_shm+0002D0 (??, ??, ??, ??, ??,
  ??)
  [005CA8B4]vm_lsa_promote+0000B4 (??, ??, ??, ??, ??, ??)
  [005CC220]vm_lsa_set_uno+0004A0 (??, ??, ??, ??, ??, ??)
  [005D2E00]shm_findspace64g+000240 (??, ??, ??, ??, ??,
  ??, ??, ??)
  [005D4ACC]shm_findspacex+00016C (??, ??, ??, ??, ??, ??,
  ??, ??)
  [005DA1B4]_shmat64+000494 (0010005500100055,
  0A00000040000000,
  0000000000000000)
  [005DE820]shmat+000080 (0010005500100055,
  0A00000040000000,
  0000000000000000)
  [0000386C]ovlya_addr_sc_flih_main+00014C ()
  [kdb_get_virtual_memory] no real storage @
  FFFFFFFFFFF4340
  [101ADE308]0000000101ADE308 ()
  
  This problem is with 1TB shared memory segment aliases.
  

Local fix

• Avoid use of unshared aliases on SPLPAR systems, either
  by
  running Dedicated systems, or disabling unshared aliases,
  as follows:
  vmo -r -o shm_1tb_unsh_enable=0
  then run bosboot and reboot.
  

Problem summary

• SPLPAR System crash while promoting to an Unshared 1TB alias.
  Trace back like:
   00022080 abend_trap+000000
   00035BC4 v_slb_clr_1tb+000164
   00035DF8 v_stab_clr_range+000178
   0002DAF8 as_make_unsh_alias_st+000038
   0002DFC0 as_makealias+000280
   00033D5C as_create_alias+0000DC
   005CA6B0 vm_lsa_promote_shm+0002D0
   005CA8B4 vm_lsa_promote+0000B4
   005CC220 vm_lsa_set_uno+0004A0
   005D2E00 shm_findspace64g+000240
   005D4ACC shm_findspacex+00016C
   005DA1B4 _shmat64+000494
  

Problem conclusion

• Correctly handle unshared 1TB alias promotion.
  

Temporary fix

Comments

APAR Information

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

  IV01654

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

Fix information

• Fixed component name

  AIX V7.1

• Fixed component ID

  5765H4000

Applicable component levels

• R710 PSY U838090

     UP11/10/05 I 1000

PTF to Fileset Mapping

• U838090 bos.mp64 7.1.1.0