1 files changed, 33 insertions, 22 deletions

diff --git a/src/cpu/base.cc b/src/cpu/base.cc
index c1b1e6d36..ff832f562 100644
--- a/src/cpu/base.cc
+++ b/src/cpu/base.cc
@@ -389,17 +389,21 @@ BaseCPU::takeOverFrom(BaseCPU *oldCPU)
         MasterPort *new_dtb_port = newTC->getDTBPtr()->getMasterPort();
 
         // Move over any table walker ports if they exist
-        if (new_itb_port && !new_itb_port->isConnected()) {
+        if (new_itb_port) {
+            assert(!new_itb_port->isConnected());
             assert(old_itb_port);
+            assert(old_itb_port->isConnected());
             SlavePort &slavePort = old_itb_port->getSlavePort();
+            old_itb_port->unbind();
             new_itb_port->bind(slavePort);
-            old_itb_port->unBind();
         }
-        if (new_dtb_port && !new_dtb_port->isConnected()) {
+        if (new_dtb_port) {
+            assert(!new_dtb_port->isConnected());
             assert(old_dtb_port);
+            assert(old_dtb_port->isConnected());
             SlavePort &slavePort = old_dtb_port->getSlavePort();
+            old_dtb_port->unbind();
             new_dtb_port->bind(slavePort);
-            old_dtb_port->unBind();
         }
 
         // Checker whether or not we have to transfer CheckerCPU
@@ -417,17 +421,21 @@ BaseCPU::takeOverFrom(BaseCPU *oldCPU)
                 newChecker->getDTBPtr()->getMasterPort();
 
             // Move over any table walker ports if they exist for checker
-            if (new_checker_itb_port && !new_checker_itb_port->isConnected()) {
+            if (new_checker_itb_port) {
+                assert(!new_checker_itb_port->isConnected());
                 assert(old_checker_itb_port);
-                SlavePort &slavePort = old_checker_itb_port->getSlavePort();;
+                assert(old_checker_itb_port->isConnected());
+                SlavePort &slavePort = old_checker_itb_port->getSlavePort();
+                old_checker_itb_port->unbind();
                 new_checker_itb_port->bind(slavePort);
-                old_checker_itb_port->unBind();
             }
-            if (new_checker_dtb_port && !new_checker_dtb_port->isConnected()) {
+            if (new_checker_dtb_port) {
+                assert(!new_checker_dtb_port->isConnected());
                 assert(old_checker_dtb_port);
-                SlavePort &slavePort = old_checker_dtb_port->getSlavePort();;
+                assert(old_checker_dtb_port->isConnected());
+                SlavePort &slavePort = old_checker_dtb_port->getSlavePort();
+                old_checker_dtb_port->unbind();
                 new_checker_dtb_port->bind(slavePort);
-                old_checker_dtb_port->unBind();
             }
         }
     }
@@ -444,18 +452,21 @@ BaseCPU::takeOverFrom(BaseCPU *oldCPU)
             schedule(profileEvent, curTick());
     }
 
-    // Connect new CPU to old CPU's memory only if new CPU isn't
-    // connected to anything.  Also connect old CPU's memory to new
-    // CPU.
-    if (!getInstPort().isConnected()) {
-        getInstPort().bind(oldCPU->getInstPort().getSlavePort());
-        oldCPU->getInstPort().unBind();
-    }
-
-    if (!getDataPort().isConnected()) {
-        getDataPort().bind(oldCPU->getDataPort().getSlavePort());
-        oldCPU->getDataPort().unBind();
-    }
+    // All CPUs have an instruction and a data port, and the new CPU's
+    // ports are dangling while the old CPU has its ports connected
+    // already. Unbind the old CPU and then bind the ports of the one
+    // we are switching to.
+    assert(!getInstPort().isConnected());
+    assert(oldCPU->getInstPort().isConnected());
+    SlavePort &inst_peer_port = oldCPU->getInstPort().getSlavePort();
+    oldCPU->getInstPort().unbind();
+    getInstPort().bind(inst_peer_port);
+
+    assert(!getDataPort().isConnected());
+    assert(oldCPU->getDataPort().isConnected());
+    SlavePort &data_peer_port = oldCPU->getDataPort().getSlavePort();
+    oldCPU->getDataPort().unbind();
+    getDataPort().bind(data_peer_port);
 }