Actually we don't really need a goroutine here

federationapi/internal/perform.go

@@ -211,7 +211,7 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 
 	// Sanity-check the join response to ensure that it has a create
 	// event, that the room version is known, etc.
-	if err := sanityCheckAuthChain(respSendJoin.AuthEvents); err != nil {
+	if err = sanityCheckAuthChain(respSendJoin.AuthEvents); err != nil {
 		return fmt.Errorf("sanityCheckAuthChain: %w", err)
 	}
 
@@ -220,16 +220,17 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 	// to complete, but if the client does give up waiting, we'll
 	// still continue to process the join anyway so that we don't
 	// waste the effort.
-	go func() {
 	// TODO: Can we expand Check here to return a list of missing auth
 	// events rather than failing one at a time?
-		respState, err := respSendJoin.Check(context.Background(), r.keyRing, event, federatedAuthProvider(ctx, r.federation, r.keyRing, serverName))
+	var respState *gomatrixserverlib.RespState
+	respState, err = respSendJoin.Check(
+		context.Background(),
+		r.keyRing,
+		event,
+		federatedAuthProvider(ctx, r.federation, r.keyRing, serverName),
+	)
 	if err != nil {
-			logrus.WithFields(logrus.Fields{
+		return fmt.Errorf("respSendJoin.Check: %w", err)
-				"room_id": roomID,
-				"user_id": userID,
-			}).WithError(err).Error("Failed to process room join response")
-			return
 	}
 
 	// If we successfully performed a send_join above then the other
@@ -245,13 +246,8 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 		nil,
 		false,
 	); err != nil {
-			logrus.WithFields(logrus.Fields{
+		return fmt.Errorf("roomserverAPI.SendEventWithState: %w", err)
-				"room_id": roomID,
-				"user_id": userID,
-			}).WithError(err).Error("Failed to send room join response to roomserver")
-			return
 	}
-	}()
 
 	return nil
 }