diff --git a/tests/sys/common/vnet.subr b/tests/sys/common/vnet.subr
--- a/tests/sys/common/vnet.subr
+++ b/tests/sys/common/vnet.subr
@@ -24,6 +24,13 @@
 	echo ${ifname}
 }
 
+vnet_mkvlan()
+{
+	ifname=$(ifconfig vlan create)
+	echo ${ifname} >> created_interfaces.lst
+	echo ${ifname}
+}
+
 vnet_mkloopback()
 {
 	ifname=$(ifconfig lo create)
diff --git a/tests/sys/netpfil/pf/altq.sh b/tests/sys/netpfil/pf/altq.sh
--- a/tests/sys/netpfil/pf/altq.sh
+++ b/tests/sys/netpfil/pf/altq.sh
@@ -86,9 +86,69 @@
 	altq_cleanup
 }
 
+atf_test_case "cbq_vlan" "cleanup"
+cbq_vlan_head()
+{
+	atf_set descr 'CBQ over VLAN test'
+	atf_set require.user root
+}
+
+cbq_vlan_body()
+{
+	altq_init
+	is_altq_supported cbq
+
+	epair=$(vnet_mkepair)
+	vnet_mkjail altq_cbq_vlan ${epair}b
+
+	vlan=$(vnet_mkvlan)
+	ifconfig ${vlan} vlan 42 vlandev ${epair}a
+	ifconfig ${vlan} 192.0.2.1/24 up
+	ifconfig ${epair}a up
+
+	vlanj=$(jexec altq_cbq_vlan ifconfig vlan create)
+	echo ${vlanj} >> created_interfaces.lst
+
+	jexec altq_cbq_vlan ifconfig ${epair}b up
+	jexec altq_cbq_vlan ifconfig ${vlanj} vlan 42 vlandev ${epair}b
+	jexec altq_cbq_vlan ifconfig ${vlanj} 192.0.2.2/24 up
+
+	# Sanity check
+	atf_check -s exit:0 -o ignore ping -i .1 -c 3 -s 1200 192.0.2.2
+
+	jexec altq_cbq_vlan pfctl -e
+	pft_set_rules altq_cbq_vlan \
+		"altq on ${vlanj} bandwidth 14000b cbq queue { default }" \
+		"queue default bandwidth 14000b cbq(default) { slow } " \
+		"queue slow bandwidth 6000b cbq(borrow)" \
+		"match proto icmp queue slow" \
+		"match proto tcp queue default" \
+		"pass"
+
+	# single ping succeeds just fine
+	atf_check -s exit:0 -o ignore ping -c 1 192.0.2.2
+
+	# "Saturate the link"
+	ping -i .01 -c 50 -s 1200 192.0.2.2
+
+	# We should now be hitting the limits and get these packet dropped.
+	rcv=$(ping -i .1 -c 5 -s 1200 192.0.2.2 | tr "," "\n" | awk '/packets received/ { print $1; }')
+	echo "Received $rcv packets"
+	if [ ${rcv} -gt 1 ]
+	then
+		atf_fail "Received ${rcv} packets in a saturated link"
+	fi
+}
+
+cbq_vlan_cleanup()
+{
+	altq_cleanup
+}
+
 atf_init_test_cases()
 {
 	atf_add_test_case "hfsc"
 	atf_add_test_case "match"
+	atf_add_test_case "cbq_vlan"
 }