nfsd: clean up grace period on early exit

If nfsd was shut down before the grace period ended, we could end up
with a freed object still on grace_list.  Thanks to Jeff Moyer for
reporting the resulting list corruption warnings.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Tested-by: Jeff Moyer <jmoyer@redhat.com>
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index c631a83..56b0767 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -181,6 +181,7 @@
 	}
 	flush_signals(current);
 	cancel_delayed_work_sync(&grace_period_end);
+	locks_end_grace(&lockd_manager);
 	if (nlmsvc_ops)
 		nlmsvc_invalidate_all();
 	nlm_shutdown_hosts();