diff --git a/configs/test/SysPaths.py b/configs/test/SysPaths.py
index 9acfedc8b..e458d5225 100644
--- a/configs/test/SysPaths.py
+++ b/configs/test/SysPaths.py
@@ -13,7 +13,7 @@ def load_defaults():
         try:
                 path = env['M5_PATH'].split(':')
         except KeyError:
-                path = [ '/dist/m5/system' ]
+                path = [ '/dist/m5/system', '/n/poolfs/z/dist/m5/system' ]
 
         for systemdir in path:
             if os.path.isdir(systemdir):
diff --git a/src/dev/io_device.cc b/src/dev/io_device.cc
index 485216874..e769ef037 100644
--- a/src/dev/io_device.cc
+++ b/src/dev/io_device.cc
@@ -62,13 +62,14 @@ PioPort::getDeviceAddressRanges(AddrRangeList &resp, AddrRangeList &snoop)
 void
 PioPort::recvRetry()
 {
-    Packet* pkt = transmitList.front();
-    if (Port::sendTiming(pkt)) {
-        transmitList.pop_front();
+    bool result = true;
+    while (result && transmitList.size()) {
+        result = Port::sendTiming(transmitList.front());
+        if (result)
+            transmitList.pop_front();
     }
 }
 
-
 void
 PioPort::SendEvent::process()
 {
@@ -83,10 +84,20 @@ PioPort::SendEvent::process()
 bool
 PioPort::recvTiming(Packet *pkt)
 {
-    Tick latency = device->recvAtomic(pkt);
-    // turn packet around to go back to requester
-    pkt->makeTimingResponse();
-    sendTiming(pkt, latency);
+    if (pkt->result == Packet::Nacked) {
+        pkt->reinitNacked();
+        if (transmitList.size()) {
+             transmitList.push_front(pkt);
+        } else {
+            if (!Port::sendTiming(pkt))
+                transmitList.push_front(pkt);
+        }
+    } else {
+        Tick latency = device->recvAtomic(pkt);
+        // turn packet around to go back to requester
+        pkt->makeTimingResponse();
+        sendTiming(pkt, latency);
+    }
     return true;
 }
 
diff --git a/src/dev/io_device.hh b/src/dev/io_device.hh
index cd2c25eeb..a2b61c7f4 100644
--- a/src/dev/io_device.hh
+++ b/src/dev/io_device.hh
@@ -119,30 +119,29 @@ class PioPort : public Port
 };
 
 
-struct DmaReqState : public Packet::SenderState
-{
-    /** Event to call on the device when this transaction (all packets)
-     * complete. */
-    Event *completionEvent;
-
-    /** Where we came from for some sanity checking. */
-    Port *outPort;
-
-    /** Total number of bytes that this transaction involves. */
-    Addr totBytes;
-
-    /** Number of bytes that have been acked for this transaction. */
-    Addr numBytes;
-
-    bool final;
-    DmaReqState(Event *ce, Port *p, Addr tb)
-        : completionEvent(ce), outPort(p), totBytes(tb), numBytes(0)
-    {}
-};
-
 class DmaPort : public Port
 {
   protected:
+    struct DmaReqState : public Packet::SenderState
+    {
+        /** Event to call on the device when this transaction (all packets)
+         * complete. */
+        Event *completionEvent;
+
+        /** Where we came from for some sanity checking. */
+        Port *outPort;
+
+        /** Total number of bytes that this transaction involves. */
+        Addr totBytes;
+
+        /** Number of bytes that have been acked for this transaction. */
+        Addr numBytes;
+
+        DmaReqState(Event *ce, Port *p, Addr tb)
+            : completionEvent(ce), outPort(p), totBytes(tb), numBytes(0)
+        {}
+    };
+
     DmaDevice *device;
     std::list<Packet*> transmitList;