OPatch failed with error code 73: LsInventorySession failed: OracleHomeInventory gets null oracleHom

I am getting this error. I have tried to repair it, but no success.

$ opatch lsinventory -invPtrLoc /software/oracle/db11g01/oraInst.loc
Oracle Interim Patch Installer version 11.2.0.3.0
Copyright (c) 2012, Oracle Corporation.  All rights reserved.

Oracle Home       : /software/oracle/db11g01
Central Inventory : /software/oracle/oraInventory
   from           : /software/oracle/db11g01/oraInst.loc
OPatch version    : 11.2.0.3.0
OUI version       : 11.2.0.3.0
Log file location : /software/oracle/db11g01/cfgtoollogs/opatch/opatch2013-09-06_11-54-35AM_1.log

List of Homes on this system:

  Home name= agt1202, Location= "/software/oracle/agent12c/core/12.1.0.2.0"
  Home name= sbin12c1, Location= "/software/oracle/agent12c/sbin"
  Home name= oracle_sysman_oh_12_1_0_2_0_discovery_Home0, Location= "/software/oracle/agent12c/core/12.1.0.2.0/../../plugins/oracle.sysman.oh.discovery.plugin_12.1.0.2.0"