diff --git a/Source/Core/Common/MemoryUtil.cpp b/Source/Core/Common/MemoryUtil.cpp
index fd88726814..87cc7812e0 100644
--- a/Source/Core/Common/MemoryUtil.cpp
+++ b/Source/Core/Common/MemoryUtil.cpp
@@ -21,6 +21,10 @@
 #include <sys/mman.h>
 #endif
 
+// Valgrind doesn't support MAP_32BIT.
+// Uncomment the following line to be able to run Dolphin in Valgrind.
+//#undef MAP_32BIT
+
 #if !defined(_WIN32) && defined(_M_X86_64) && !defined(MAP_32BIT)
 #include <unistd.h>
 #define PAGE_MASK     (getpagesize() - 1)