1 files changed, 31 insertions, 24 deletions

diff --git a/src/usr/diag/attn/attnmem.C b/src/usr/diag/attn/attnmem.C
index 53af72c94..e33a05772 100644
--- a/src/usr/diag/attn/attnmem.C
+++ b/src/usr/diag/attn/attnmem.C
@@ -1,26 +1,25 @@
-/*  IBM_PROLOG_BEGIN_TAG
- *  This is an automatically generated prolog.
- *
- *  $Source: src/usr/diag/attn/attnmem.C $
- *
- *  IBM CONFIDENTIAL
- *
- *  COPYRIGHT International Business Machines Corp. 2012
- *
- *  p1
- *
- *  Object Code Only (OCO) source materials
- *  Licensed Internal Code Source Materials
- *  IBM HostBoot Licensed Internal Code
- *
- *  The source code for this program is not published or other-
- *  wise divested of its trade secrets, irrespective of what has
- *  been deposited with the U.S. Copyright Office.
- *
- *  Origin: 30
- *
- *  IBM_PROLOG_END_TAG
- */
+/* IBM_PROLOG_BEGIN_TAG                                                   */
+/* This is an automatically generated prolog.                             */
+/*                                                                        */
+/* $Source: src/usr/diag/attn/attnmem.C $                                 */
+/*                                                                        */
+/* IBM CONFIDENTIAL                                                       */
+/*                                                                        */
+/* COPYRIGHT International Business Machines Corp. 2012,2013              */
+/*                                                                        */
+/* p1                                                                     */
+/*                                                                        */
+/* Object Code Only (OCO) source materials                                */
+/* Licensed Internal Code Source Materials                                */
+/* IBM HostBoot Licensed Internal Code                                    */
+/*                                                                        */
+/* The source code for this program is not published or otherwise         */
+/* divested of its trade secrets, irrespective of what has been           */
+/* deposited with the U.S. Copyright Office.                              */
+/*                                                                        */
+/* Origin: 30                                                             */
+/*                                                                        */
+/* IBM_PROLOG_END_TAG                                                     */
 /**
  * @file attnmem.C
  *
@@ -128,7 +127,7 @@ errlHndl_t MemOps::query(const AttnData & i_attnToCheck, bool & o_active)
 
     do
     {
-        TargetHandle_t mcs =  getTargetService().getMcs(mem);
+        TargetHandle_t mcs = getTargetService().getMcs(mem);
 
         MCI::getCheckbits(i_attnToCheck.attnType, checkbits);
 
@@ -200,6 +199,14 @@ void resolveMcs(uint64_t i_mcs, void * i_data)
                 AttnData d;
                 d.targetHndl = getTargetService().getMembuf(mcs);
 
+                if(!d.targetHndl)
+                {
+                    // this membuf not functional
+                    // or nothing is attached to this MCS
+
+                    break;
+                }
+
                 d.attnType = static_cast<ATTENTION_VALUE_TYPE>(type);
 
                 args->list->add(Attention(d, args->ops));