diff --git a/drivers/staging/lustre/lustre/include/obd.h b/drivers/staging/lustre/lustre/include/obd.h
index 40909b092c36..a1bc2c478ff9 100644
--- a/drivers/staging/lustre/lustre/include/obd.h
+++ b/drivers/staging/lustre/lustre/include/obd.h
@@ -228,6 +228,12 @@ enum {
 #define MDC_MAX_RIF_DEFAULT       8
 #define MDC_MAX_RIF_MAX	 512
 
+enum obd_cl_sem_lock_class {
+	OBD_CLI_SEM_NORMAL,
+	OBD_CLI_SEM_MGC,
+	OBD_CLI_SEM_MDCOSC,
+};
+
 struct mdc_rpc_lock;
 struct obd_import;
 struct client_obd {
diff --git a/drivers/staging/lustre/lustre/mgc/mgc_request.c b/drivers/staging/lustre/lustre/mgc/mgc_request.c
index fbbf2762ac84..9d0bd4745865 100644
--- a/drivers/staging/lustre/lustre/mgc/mgc_request.c
+++ b/drivers/staging/lustre/lustre/mgc/mgc_request.c
@@ -496,7 +496,9 @@ static void do_requeue(struct config_llog_data *cld)
 	 * export which is being disconnected. Take the client
 	 * semaphore to make the check non-racy.
 	 */
-	down_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
+	down_read_nested(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem,
+			 OBD_CLI_SEM_MGC);
+
 	if (cld->cld_mgcexp->exp_obd->u.cli.cl_conn_count != 0) {
 		int rc;
 
diff --git a/drivers/staging/lustre/lustre/ptlrpc/sec_config.c b/drivers/staging/lustre/lustre/ptlrpc/sec_config.c
index 1238c873bfdf..c14035479c5f 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/sec_config.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/sec_config.c
@@ -815,7 +815,7 @@ void sptlrpc_conf_client_adapt(struct obd_device *obd)
 	CDEBUG(D_SEC, "obd %s\n", obd->u.cli.cl_target_uuid.uuid);
 
 	/* serialize with connect/disconnect import */
-	down_read(&obd->u.cli.cl_sem);
+	down_read_nested(&obd->u.cli.cl_sem, OBD_CLI_SEM_MDCOSC);
 
 	imp = obd->u.cli.cl_import;
 	if (imp) {