diff -r 24b06cbf2d67 -r 78597062cf81 src/arch/x86/tlb.cc
--- a/src/arch/x86/tlb.cc	Sun Apr 22 05:20:44 2012 -0700
+++ b/src/arch/x86/tlb.cc	Sun Apr 22 05:21:06 2012 -0700
@@ -103,6 +103,14 @@
     TlbEntry *newEntry = NULL;
     if (freeList.empty())
         evictLRU();
+
+    // If somebody beat us to it, just use that existing entry.
+    newEntry = trie.lookup(vpn);
+    if (newEntry) {
+        assert(newEntry->vaddr = vpn);
+        return newEntry;
+    }
+
     newEntry = freeList.front();
     freeList.pop_front();
 
@@ -110,7 +118,7 @@
     newEntry->lruSeq = nextSeq();
     newEntry->vaddr = vpn;
     newEntry->trieHandle =
-        trie.insert(vpn, TlbEntryTrie::MaxBits - entry.logBytes, newEntry);
+    trie.insert(vpn, TlbEntryTrie::MaxBits - entry.logBytes, newEntry);
     return newEntry;
 }