DO NOT MERGE: Do not hold mLock when calling GNSS HAL

Test: on device
Bug: 156867071
Change-Id: I57c3bfb8148350855af1dc4b662526a4e6043b8e

services/core/java/com/android/server/location/LocationManagerService.java

@@ -231,7 +231,7 @@ public class LocationManagerService extends ILocationManager.Stub {
     private final AppForegroundHelper mAppForegroundHelper;
     private final LocationUsageLogger mLocationUsageLogger;
 
-    @Nullable private GnssManagerService mGnssManagerService = null;
+    @Nullable private volatile GnssManagerService mGnssManagerService = null;
 
     private final PassiveLocationProviderManager mPassiveManager;
 
@@ -381,6 +381,10 @@ public class LocationManagerService extends ILocationManager.Stub {
             // prepare providers
             initializeProvidersLocked();
         }
+
+        // initialize gnss last because it has no awareness of boot phases and blindly assumes that
+        // all other location providers are loaded at initialization
+        initializeGnss();
     }
 
     private void onAppOpChanged(String packageName) {
@@ -602,16 +606,19 @@ public class LocationManagerService extends ILocationManager.Stub {
             }
             manager.setMockProvider(new MockProvider(properties));
         }
+    }
 
-        // initialize gnss last because it has no awareness of boot phases and blindly assumes that
-        // all other location providers are loaded at initialization
+    private void initializeGnss() {
+        // Do not hold mLock when calling GnssManagerService#isGnssSupported() which calls into HAL.
         if (GnssManagerService.isGnssSupported()) {
             mGnssManagerService = new GnssManagerService(mContext, mAppOpsHelper, mSettingsHelper,
                     mAppForegroundHelper, mLocationUsageLogger);
             mGnssManagerService.onSystemReady();
 
             LocationProviderManager gnssManager = new LocationProviderManager(GPS_PROVIDER);
-            mProviderManagers.add(gnssManager);
+            synchronized (mLock) {
+                mProviderManagers.add(gnssManager);
+            }
             gnssManager.setRealProvider(mGnssManagerService.getGnssLocationProvider());
 
             // bind to geofence proxy