diff --git a/Tethering/src/android/net/ip/IpServer.java b/Tethering/src/android/net/ip/IpServer.java
index c065cd6..a8c8408 100644
--- a/Tethering/src/android/net/ip/IpServer.java
+++ b/Tethering/src/android/net/ip/IpServer.java
@@ -33,7 +33,6 @@
 
 import static com.android.net.module.util.Inet4AddressUtils.intToInet4AddressHTH;
 import static com.android.net.module.util.NetworkStackConstants.RFC7421_PREFIX_LENGTH;
-import static com.android.networkstack.tethering.TetheringConfiguration.USE_SYNC_SM;
 import static com.android.networkstack.tethering.UpstreamNetworkState.isVcnInterface;
 import static com.android.networkstack.tethering.util.PrefixUtils.asIpPrefix;
 import static com.android.networkstack.tethering.util.TetheringMessageBase.BASE_IPSERVER;
@@ -316,6 +315,7 @@
 
     private final TetheringMetrics mTetheringMetrics;
     private final Handler mHandler;
+    private final boolean mIsSyncSM;
 
     // TODO: Add a dependency object to pass the data members or variables from the tethering
     // object. It helps to reduce the arguments of the constructor.
@@ -325,7 +325,7 @@
             @Nullable LateSdk<RoutingCoordinatorManager> routingCoordinator, Callback callback,
             TetheringConfiguration config, PrivateAddressCoordinator addressCoordinator,
             TetheringMetrics tetheringMetrics, Dependencies deps) {
-        super(ifaceName, USE_SYNC_SM ? null : handler.getLooper());
+        super(ifaceName, config.isSyncSM() ? null : handler.getLooper());
         mHandler = handler;
         mLog = log.forSubComponent(ifaceName);
         mNetd = netd;
@@ -338,6 +338,7 @@
         mLinkProperties = new LinkProperties();
         mUsingLegacyDhcp = config.useLegacyDhcpServer();
         mP2pLeasesSubnetPrefixLength = config.getP2pLeasesSubnetPrefixLength();
+        mIsSyncSM = config.isSyncSM();
         mPrivateAddressCoordinator = addressCoordinator;
         mDeps = deps;
         mTetheringMetrics = tetheringMetrics;
@@ -515,7 +516,7 @@
 
         private void handleError() {
             mLastError = TETHER_ERROR_DHCPSERVER_ERROR;
-            if (USE_SYNC_SM) {
+            if (mIsSyncSM) {
                 sendMessage(CMD_SERVICE_FAILED_TO_START, TETHER_ERROR_DHCPSERVER_ERROR);
             } else {
                 sendMessageAtFrontOfQueueToAsyncSM(CMD_SERVICE_FAILED_TO_START,
@@ -1170,7 +1171,7 @@
                 // in previous versions of the mainline module.
                 // TODO : remove sendMessageAtFrontOfQueueToAsyncSM after migrating to the Sync
                 // StateMachine.
-                if (USE_SYNC_SM) {
+                if (mIsSyncSM) {
                     sendSelfMessageToSyncSM(CMD_SERVICE_FAILED_TO_START, mLastError);
                 } else {
                     sendMessageAtFrontOfQueueToAsyncSM(CMD_SERVICE_FAILED_TO_START, mLastError);
diff --git a/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java b/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java
index 0678525..d09183a 100644
--- a/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java
+++ b/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java
@@ -132,15 +132,15 @@
 
     public static final String TETHER_FORCE_RANDOM_PREFIX_BASE_SELECTION =
             "tether_force_random_prefix_base_selection";
+
+    public static final String TETHER_ENABLE_SYNC_SM = "tether_enable_sync_sm";
+
     /**
      * Default value that used to periodic polls tether offload stats from tethering offload HAL
      * to make the data warnings work.
      */
     public static final int DEFAULT_TETHER_OFFLOAD_POLL_INTERVAL_MS = 5000;
 
-    /** A flag for using synchronous or asynchronous state machine. */
-    public static final boolean USE_SYNC_SM = false;
-
     public final String[] tetherableUsbRegexs;
     public final String[] tetherableWifiRegexs;
     public final String[] tetherableWigigRegexs;
@@ -174,6 +174,7 @@
 
     private final boolean mEnableWearTethering;
     private final boolean mRandomPrefixBase;
+    private final boolean mEnableSyncSm;
 
     private final int mUsbTetheringFunction;
     protected final ContentResolver mContentResolver;
@@ -292,6 +293,7 @@
         mEnableWearTethering = shouldEnableWearTethering(ctx);
 
         mRandomPrefixBase = mDeps.isFeatureEnabled(ctx, TETHER_FORCE_RANDOM_PREFIX_BASE_SELECTION);
+        mEnableSyncSm = mDeps.isFeatureEnabled(ctx, TETHER_ENABLE_SYNC_SM);
 
         configLog.log(toString());
     }
@@ -385,6 +387,10 @@
         return mRandomPrefixBase;
     }
 
+    public boolean isSyncSM() {
+        return mEnableSyncSm;
+    }
+
     /** Does the dumping.*/
     public void dump(PrintWriter pw) {
         pw.print("activeDataSubId: ");
@@ -438,6 +444,9 @@
 
         pw.print("mRandomPrefixBase: ");
         pw.println(mRandomPrefixBase);
+
+        pw.print("mEnableSyncSm: ");
+        pw.println(mEnableSyncSm);
     }
 
     /** Returns the string representation of this object.*/