diff --git a/libs/binder/IServiceManager.cpp b/libs/binder/IServiceManager.cpp
index 5ca9156..328653a 100644
--- a/libs/binder/IServiceManager.cpp
+++ b/libs/binder/IServiceManager.cpp
@@ -85,10 +85,11 @@
     sp<AidlServiceManager> mTheRealServiceManager;
 };
 
+static Mutex gDefaultServiceManagerLock;
+static sp<IServiceManager> gDefaultServiceManager;
+
 sp<IServiceManager> defaultServiceManager()
 {
-    static Mutex gDefaultServiceManagerLock;
-    static sp<IServiceManager> gDefaultServiceManager;
 
     if (gDefaultServiceManager != nullptr) return gDefaultServiceManager;
 
@@ -106,6 +107,11 @@
     return gDefaultServiceManager;
 }
 
+void setDefaultServiceManager(const sp<IServiceManager>& sm) {
+  AutoMutex _l(gDefaultServiceManagerLock);
+  gDefaultServiceManager = sm;
+}
+
 #if !defined(__ANDROID_VNDK__) && defined(__ANDROID__)
 // IPermissionController is not accessible to vendors