diff --git a/src/sim/process.cc b/src/sim/process.cc
index f47dbd59c6..7b6e2d0de2 100644
--- a/src/sim/process.cc
+++ b/src/sim/process.cc
@@ -401,7 +401,7 @@ Process::unserialize(CheckpointIn &cp)
 }
 
 bool
-Process::map(Addr vaddr, Addr paddr, int size, bool cacheable)
+Process::map(Addr vaddr, Addr paddr, int64_t size, bool cacheable)
 {
     pTable->map(vaddr, paddr, size,
                 cacheable ? EmulationPageTable::MappingFlags(0) :
diff --git a/src/sim/process.hh b/src/sim/process.hh
index d6d30cebc8..9d04ccd094 100644
--- a/src/sim/process.hh
+++ b/src/sim/process.hh
@@ -158,7 +158,7 @@ class Process : public SimObject
      * @return True if the map operation was successful.  (At this
      *           point in time, the map operation always succeeds.)
      */
-    bool map(Addr vaddr, Addr paddr, int size, bool cacheable = true);
+    bool map(Addr vaddr, Addr paddr, int64_t size, bool cacheable = true);
 
     void replicatePage(Addr vaddr, Addr new_paddr, ThreadContext *old_tc,
                        ThreadContext *new_tc, bool alloc_page);