diff --git a/sys/dev/virtio/network/if_vtnet.c b/sys/dev/virtio/network/if_vtnet.c
--- a/sys/dev/virtio/network/if_vtnet.c
+++ b/sys/dev/virtio/network/if_vtnet.c
@@ -1355,11 +1355,11 @@
 	}
 	if (mask & IFCAP_TSO4) {
 		if_togglecapenable(ifp, IFCAP_TSO4);
-		if_togglehwassist(ifp, IFCAP_TSO4);
+		if_togglehwassist(ifp, CSUM_IP_TSO);
 	}
 	if (mask & IFCAP_TSO6) {
 		if_togglecapenable(ifp, IFCAP_TSO6);
-		if_togglehwassist(ifp, IFCAP_TSO6);
+		if_togglehwassist(ifp, CSUM_IP6_TSO);
 	}
 
 	if (mask & (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6 | IFCAP_LRO)) {