diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index 72b6c58..cde5650 100644
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -63,9 +63,14 @@
 
 	ops = clp->cl_mvops->state_renewal_ops;
 	dprintk("%s: start\n", __func__);
-	/* Are there any active superblocks? */
-	if (list_empty(&clp->cl_superblocks))
+
+	rcu_read_lock();
+	if (list_empty(&clp->cl_superblocks)) {
+		rcu_read_unlock();
 		goto out;
+	}
+	rcu_read_unlock();
+
 	spin_lock(&clp->cl_lock);
 	lease = clp->cl_lease_time;
 	last = clp->cl_last_renewal;