diff --git a/services/core/java/com/android/server/vibrator/VibrationSettings.java b/services/core/java/com/android/server/vibrator/VibrationSettings.java
index 9cf0834..749cd8e 100644
--- a/services/core/java/com/android/server/vibrator/VibrationSettings.java
+++ b/services/core/java/com/android/server/vibrator/VibrationSettings.java
@@ -731,18 +731,24 @@
         private final SparseArray<Integer> mProcStatesCache = new SparseArray<>();
 
         public boolean isUidForeground(int uid) {
-            return mProcStatesCache.get(uid, ActivityManager.PROCESS_STATE_IMPORTANT_FOREGROUND)
-                    <= ActivityManager.PROCESS_STATE_IMPORTANT_FOREGROUND;
+            synchronized (this) {
+                return mProcStatesCache.get(uid, ActivityManager.PROCESS_STATE_IMPORTANT_FOREGROUND)
+                        <= ActivityManager.PROCESS_STATE_IMPORTANT_FOREGROUND;
+            }
         }
 
         @Override
         public void onUidGone(int uid, boolean disabled) {
-            mProcStatesCache.delete(uid);
+            synchronized (this) {
+                mProcStatesCache.delete(uid);
+            }
         }
 
         @Override
         public void onUidStateChanged(int uid, int procState, long procStateSeq, int capability) {
-            mProcStatesCache.put(uid, procState);
+            synchronized (this) {
+                mProcStatesCache.put(uid, procState);
+            }
         }
     }