diff --git a/services/core/java/com/android/server/am/AppTaskImpl.java b/services/core/java/com/android/server/am/AppTaskImpl.java
index c22dedc4073fc..a1f1ff9cc3ec5 100644
--- a/services/core/java/com/android/server/am/AppTaskImpl.java
+++ b/services/core/java/com/android/server/am/AppTaskImpl.java
@@ -97,7 +97,7 @@ class AppTaskImpl extends IAppTask.Stub {
         final int callingUid = Binder.getCallingUid();
         final long origId = Binder.clearCallingIdentity();
         try {
-            synchronized (this) {
+            synchronized (mService.mGlobalLock) {
                 mService.mStackSupervisor.startActivityFromRecents(callingPid, callingUid, mTaskId,
                         null);
             }