Index: head/sys/dev/e1000/e1000_82575.c
===================================================================
--- head/sys/dev/e1000/e1000_82575.c
+++ head/sys/dev/e1000/e1000_82575.c
@@ -1679,7 +1679,7 @@
 	case E1000_CTRL_EXT_LINK_MODE_1000BASE_KX:
 		/* disable PCS autoneg and support parallel detect only */
 		pcs_autoneg = FALSE;
-		/* fall through to default case */
+		/* FALLTHROUGH */
 	default:
 		if (hw->mac.type == e1000_82575 ||
 		    hw->mac.type == e1000_82576) {
@@ -1806,6 +1806,7 @@
 			break;
 		}
 		/* fall through for I2C based SGMII */
+		/* FALLTHROUGH */
 	case E1000_CTRL_EXT_LINK_MODE_PCIE_SERDES:
 		/* read media type from SFP EEPROM */
 		ret_val = e1000_set_sfp_media_type_82575(hw);
Index: head/sys/dev/e1000/e1000_mbx.c
===================================================================
--- head/sys/dev/e1000/e1000_mbx.c
+++ head/sys/dev/e1000/e1000_mbx.c
@@ -779,6 +779,7 @@
 		mbx->stats.reqs = 0;
 		mbx->stats.acks = 0;
 		mbx->stats.rsts = 0;
+		/* FALLTHROUGH */
 	default:
 		return E1000_SUCCESS;
 	}
Index: head/sys/dev/e1000/e1000_phy.c
===================================================================
--- head/sys/dev/e1000/e1000_phy.c
+++ head/sys/dev/e1000/e1000_phy.c
@@ -1298,6 +1298,7 @@
 			phy_data |= M88E1000_PSCR_AUTO_X_1000T;
 			break;
 		}
+		/* FALLTHROUGH */
 	case 0:
 	default:
 		phy_data |= M88E1000_PSCR_AUTO_X_MODE;
Index: head/sys/dev/e1000/e1000_vf.c
===================================================================
--- head/sys/dev/e1000/e1000_vf.c
+++ head/sys/dev/e1000/e1000_vf.c
@@ -488,8 +488,10 @@
 		break;
 	case e1000_promisc_enabled:
 		msgbuf |= E1000_VF_SET_PROMISC_MULTICAST;
+		/* FALLTHROUGH */
 	case e1000_promisc_unicast:
 		msgbuf |= E1000_VF_SET_PROMISC_UNICAST;
+		/* FALLTHROUGH */
 	case e1000_promisc_disabled:
 		break;
 	default: