diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 183003e45762..01f21b0b379a 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -783,6 +783,8 @@ static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
 			goto out_put_node;
 
 		if (reg >= ds->num_ports) {
+			dev_err(ds->dev, "port %pOF index %u exceeds num_ports (%zu)\n",
+				port, reg, ds->num_ports);
 			err = -EINVAL;
 			goto out_put_node;
 		}