diff --git a/[refs] b/[refs]
index 0e36a14c2194..c51b4db6b193 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 2561b9c1f1d63077c41903fc6ad58dc9ec47248b
+refs/heads/master: 09b9e7979378fe070784de20e50bb1d42aa643ab
diff --git a/trunk/drivers/block/drbd/drbd_worker.c b/trunk/drivers/block/drbd/drbd_worker.c
index ab5cff502f5b..e201f6f82c0e 100644
--- a/trunk/drivers/block/drbd/drbd_worker.c
+++ b/trunk/drivers/block/drbd/drbd_worker.c
@@ -1499,6 +1499,20 @@ void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side)
 			drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
 			return;
 		}
+	} else /* C_SYNC_SOURCE */ {
+		r = drbd_khelper(mdev, "before-resync-source");
+		r = (r >> 8) & 0xff;
+		if (r > 0) {
+			if (r == 3) {
+				dev_info(DEV, "before-resync-source handler returned %d, "
+					 "ignoring. Old userland tools?", r);
+			} else {
+				dev_info(DEV, "before-resync-source handler returned %d, "
+					 "dropping connection.\n", r);
+				drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
+				return;
+			}
+		}
 	}
 
 	drbd_state_lock(mdev);