diff --git a/services/audiopolicy/service/AudioPolicyService.cpp b/services/audiopolicy/service/AudioPolicyService.cpp
index 5f29d3f..fd10353 100644
--- a/services/audiopolicy/service/AudioPolicyService.cpp
+++ b/services/audiopolicy/service/AudioPolicyService.cpp
@@ -1724,6 +1724,7 @@
 }
 
 bool AudioPolicyService::UidPolicy::isA11yOnTop() {
+    Mutex::Autolock _l(mLock);
     for (const auto &uid : mCachedUids) {
         if (!isA11yUid(uid.first)) {
             continue;
diff --git a/services/audiopolicy/service/AudioPolicyService.h b/services/audiopolicy/service/AudioPolicyService.h
index a87d871..5c37f99 100644
--- a/services/audiopolicy/service/AudioPolicyService.h
+++ b/services/audiopolicy/service/AudioPolicyService.h
@@ -475,8 +475,8 @@
         Mutex mLock;
         ActivityManager mAm;
         bool mObserverRegistered = false;
-        std::unordered_map<uid_t, std::pair<bool, int>> mOverrideUids;
-        std::unordered_map<uid_t, std::pair<bool, int>> mCachedUids;
+        std::unordered_map<uid_t, std::pair<bool, int>> mOverrideUids GUARDED_BY(mLock);
+        std::unordered_map<uid_t, std::pair<bool, int>> mCachedUids GUARDED_BY(mLock);
         std::vector<uid_t> mAssistantUids;
         std::vector<uid_t> mActiveAssistantUids;
         std::vector<uid_t> mA11yUids;