diff --git a/src/vm/clsload.cpp b/src/vm/clsload.cpp
index 316e66673ba8..a31cd71a5c90 100644
--- a/src/vm/clsload.cpp
+++ b/src/vm/clsload.cpp
@@ -4192,6 +4192,15 @@ VOID ClassLoader::AddAvailableClassDontHaveLock(Module *pModule,
 #endif
 
     CrstHolder ch(&m_AvailableClassLock);
+
+    // R2R pre-computes an export table and tries to avoid populating a class hash at runtime. However the profiler can
+    // still add new types on the fly by calling here. If that occurs we fallback to the slower path of creating the
+    // in memory hashtable as usual.
+    if (!pModule->IsResource() && pModule->GetAvailableClassHash() == NULL)
+    {
+        LazyPopulateCaseSensitiveHashTables();
+    }
+
     AddAvailableClassHaveLock(
         pModule, 
         classdef, 
@@ -4386,7 +4395,9 @@ VOID ClassLoader::AddExportedTypeDontHaveLock(Module *pManifestModule,
         INJECT_FAULT(COMPlusThrowOM(););
     }
     CONTRACTL_END
-    
+
+    CrstHolder ch(&m_AvailableClassLock);
+        
     // R2R pre-computes an export table and tries to avoid populating a class hash at runtime. However the profiler can
     // still add new types on the fly by calling here. If that occurs we fallback to the slower path of creating the
     // in memory hashtable as usual.
@@ -4395,7 +4406,6 @@ VOID ClassLoader::AddExportedTypeDontHaveLock(Module *pManifestModule,
         LazyPopulateCaseSensitiveHashTables();
     }
 
-    CrstHolder ch(&m_AvailableClassLock);
     AddExportedTypeHaveLock(
         pManifestModule,
         cl,