diff -r c7358871f1e5 -r 563280b8bbc2 src/mem/cache/mshr.cc
--- a/src/mem/cache/mshr.cc	Mon Feb 18 12:03:37 2013 +0000
+++ b/src/mem/cache/mshr.cc	Mon Feb 18 13:44:17 2013 +0000
@@ -82,7 +82,10 @@
     }
 
     if (markPending) {
-        MSHR *mshr = dynamic_cast<MSHR*>(pkt->senderState);
+        // Iterate over the SenderState stack and see if we find
+        // an MSHR entry. If we do, set the downstreamPending
+        // flag. Otherwise, do nothing.
+        MSHR *mshr = pkt->findNextSenderState<MSHR>();
         if (mshr != NULL) {
             assert(!mshr->downstreamPending);
             mshr->downstreamPending = true;
@@ -130,7 +133,13 @@
     Iterator end_i = end();
     for (Iterator i = begin(); i != end_i; ++i) {
         if (i->markedPending) {
-            MSHR *mshr = dynamic_cast<MSHR*>(i->pkt->senderState);
+            // Iterate over the SenderState stack and see if we find
+            // an MSHR entry. If we find one, clear the
+            // downstreamPending flag by calling
+            // clearDownstreamPending(). This recursively clears the
+            // downstreamPending flag in all caches this packet has
+            // passed through.
+            MSHR *mshr = i->pkt->findNextSenderState<MSHR>();
             if (mshr != NULL) {
                 mshr->clearDownstreamPending();
             }
diff -r c7358871f1e5 -r 563280b8bbc2 src/mem/packet.hh
--- a/src/mem/packet.hh	Mon Feb 18 12:03:37 2013 +0000
+++ b/src/mem/packet.hh	Mon Feb 18 13:44:17 2013 +0000
@@ -454,6 +454,25 @@
      */
     SenderState *popSenderState();
 
+    /**
+     * Go through the sender state stack and return the first instance
+     * that is of type T (as determined by a dynamic_cast). If there
+     * is no sender state of type T, NULL is returned.
+     *
+     * @return The topmost state of type T
+     */
+    template <typename T>
+    T * findNextSenderState() const
+    {
+        T *t = NULL;
+        SenderState* sender_state = senderState;
+        while (t == NULL && sender_state != NULL) {
+            t = dynamic_cast<T*>(sender_state);
+            sender_state = sender_state->predecessor;
+        }
+        return t;
+    }
+
     /// Return the string name of the cmd field (for debugging and
     /// tracing).
     const std::string &cmdString() const { return cmd.toString(); }