diff --git a/libs/gui/SensorManager.cpp b/libs/gui/SensorManager.cpp
index 225bfa8..2e245bf 100644
--- a/libs/gui/SensorManager.cpp
+++ b/libs/gui/SensorManager.cpp
@@ -90,7 +90,7 @@
 
 SensorManager::SensorManager(const String16& opPackageName)
     : mSensorList(0), mOpPackageName(opPackageName) {
-    // okay we're not locked here, but it's not needed during construction
+    Mutex::Autolock _l(mLock);
     assertStateLocked();
 }