diff --git a/etc/mtree/BSD.tests.dist b/etc/mtree/BSD.tests.dist
index 37af92ad561c..9dc18753b2de 100644
--- a/etc/mtree/BSD.tests.dist
+++ b/etc/mtree/BSD.tests.dist
@@ -730,6 +730,8 @@
         ..
         mqueue
         ..
+        net
+        ..
         netinet
         ..
         netipsec
diff --git a/tests/sys/net/Makefile b/tests/sys/net/Makefile
new file mode 100644
index 000000000000..681a1408ab17
--- /dev/null
+++ b/tests/sys/net/Makefile
@@ -0,0 +1,21 @@
+# $FreeBSD$
+
+.include <bsd.own.mk>
+
+TESTSDIR=	${TESTSBASE}/sys/net
+BINDIR=		${TESTSDIR}
+
+ATF_TESTS_SH+=	if_lagg_test
+ATF_TESTS_SH+=	if_clone_test
+
+# The tests are written to be run in parallel, but doing so leads to random
+# panics.  I think it's because the kernel's list of interfaces isn't properly
+# locked.
+TEST_METADATA+=	is_exclusive=true
+
+MAN=
+PROG=		randsleep
+
+WARNS?=		6
+
+.include <bsd.test.mk>
diff --git a/tests/sys/net/if_clone_test.sh b/tests/sys/net/if_clone_test.sh
new file mode 100755
index 000000000000..02b5e8465b64
--- /dev/null
+++ b/tests/sys/net/if_clone_test.sh
@@ -0,0 +1,511 @@
+#
+#  Copyright (c) 2014 Spectra Logic Corporation
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions
+#  are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions, and the following disclaimer,
+#     without modification.
+#  2. Redistributions in binary form must reproduce at minimum a disclaimer
+#     substantially similar to the "NO WARRANTY" disclaimer below
+#     ("Disclaimer") and any redistribution must be conditioned upon
+#     including a substantially similar Disclaimer requirement for further
+#     binary redistribution.
+#
+#  NO WARRANTY
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+#  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#  HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+#  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+#  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+#  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+#  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+#  IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGES.
+#
+#  Authors: Alan Somers         (Spectra Logic Corporation)
+#
+# $FreeBSD$
+
+# Outline:
+# For each cloned interface type, do three tests
+# 1) Create and destroy it
+# 2) Create, up, and destroy it
+# 3) Create, disable IPv6 auto address assignment, up, and destroy it
+
+TESTLEN=10	# seconds
+
+atf_test_case faith_stress cleanup
+faith_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a faith(4)"
+	atf_set "require.user" "root"
+}
+faith_stress_body()
+{
+	do_stress "faith"
+}
+faith_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case faith_up_stress cleanup
+faith_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a faith(4)"
+	atf_set "require.user" "root"
+}
+faith_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "faith" "" ""
+}
+faith_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case faith_ipv6_up_stress cleanup
+faith_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a faith(4) with IPv6"
+	atf_set "require.user" "root"
+}
+faith_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "faith" "6" ""
+}
+faith_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case gif_stress cleanup
+gif_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a gif(4)"
+	atf_set "require.user" "root"
+}
+gif_stress_body()
+{
+	do_stress "gif"
+}
+gif_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case gif_up_stress cleanup
+gif_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a gif(4)"
+	atf_set "require.user" "root"
+}
+gif_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "gif" "" "p2p"
+}
+gif_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case gif_ipv6_up_stress cleanup
+gif_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a gif(4) with IPv6"
+	atf_set "require.user" "root"
+}
+gif_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: rt_tables_get_rnh_ptr: fam out of bounds."
+	do_up_stress "gif" "6" "p2p"
+}
+gif_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case lo_stress cleanup
+lo_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy an lo(4)"
+	atf_set "require.user" "root"
+}
+lo_stress_body()
+{
+	do_stress "lo"
+}
+lo_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case lo_up_stress cleanup
+lo_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy an lo(4)"
+	atf_set "require.user" "root"
+}
+lo_up_stress_body()
+{
+	atf_skip "Quickly panics: GPF in rtsock_routemsg"
+	do_up_stress "lo" "" ""
+}
+lo_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case lo_ipv6_up_stress cleanup
+lo_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy an lo(4) with IPv6"
+	atf_set "require.user" "root"
+}
+lo_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: page fault in rtsock_addrmsg"
+	do_up_stress "lo" "6" ""
+}
+lo_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case tap_stress cleanup
+tap_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a tap(4)"
+	atf_set "require.user" "root"
+}
+tap_stress_body()
+{
+	do_stress "tap"
+}
+tap_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case tap_up_stress cleanup
+tap_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a tap(4)"
+	atf_set "require.user" "root"
+}
+tap_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "tap" "" ""
+}
+tap_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case tap_ipv6_up_stress cleanup
+tap_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a tap(4) with IPv6"
+	atf_set "require.user" "root"
+}
+tap_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: if_delmulti_locked: inconsistent ifp 0xfffff80150e44000"
+	do_up_stress "tap" "6" ""
+}
+tap_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case tun_stress cleanup
+tun_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a tun(4)"
+	atf_set "require.user" "root"
+}
+tun_stress_body()
+{
+	do_stress "tun"
+}
+tun_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case tun_up_stress cleanup
+tun_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a tun(4)"
+	atf_set "require.user" "root"
+}
+tun_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "tun" "" "p2p"
+}
+tun_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case tun_ipv6_up_stress cleanup
+tun_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a tun(4) with IPv6"
+	atf_set "require.user" "root"
+}
+tun_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "tun" "6" "p2p"
+}
+tun_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case vlan_stress cleanup
+vlan_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a vlan(4)"
+	atf_set "require.user" "root"
+}
+vlan_stress_body()
+{
+	do_stress "vlan"
+}
+vlan_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case vlan_up_stress cleanup
+vlan_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a vlan(4)"
+	atf_set "require.user" "root"
+}
+vlan_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "vlan" "" ""
+}
+vlan_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case vlan_ipv6_up_stress cleanup
+vlan_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a vlan(4) with IPv6"
+	atf_set "require.user" "root"
+}
+vlan_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "vlan" "6" ""
+}
+vlan_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case vmnet_stress cleanup
+vmnet_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a vmnet(4)"
+	atf_set "require.user" "root"
+}
+vmnet_stress_body()
+{
+	do_stress "vmnet"
+}
+vmnet_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case vmnet_up_stress cleanup
+vmnet_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a vmnet(4)"
+	atf_set "require.user" "root"
+}
+vmnet_up_stress_body()
+{
+	do_up_stress "vmnet" "" ""
+}
+vmnet_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_test_case vmnet_ipv6_up_stress cleanup
+vmnet_ipv6_up_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a vmnet(4) with IPv6"
+	atf_set "require.user" "root"
+}
+vmnet_ipv6_up_stress_body()
+{
+	atf_skip "Quickly panics: if_freemulti: protospec not NULL"
+	do_up_stress "vmnet" "6" ""
+}
+vmnet_ipv6_up_stress_cleanup()
+{
+	cleanup_ifaces
+}
+
+atf_init_test_cases()
+{
+	# TODO: add epair(4) tests, which need a different syntax
+	atf_add_test_case faith_ipv6_up_stress
+	atf_add_test_case faith_stress
+	atf_add_test_case faith_up_stress
+	atf_add_test_case gif_ipv6_up_stress
+	atf_add_test_case gif_stress
+	atf_add_test_case gif_up_stress
+	# Don't test lagg; it has its own test program
+	atf_add_test_case lo_ipv6_up_stress
+	atf_add_test_case lo_stress
+	atf_add_test_case lo_up_stress
+	atf_add_test_case tap_ipv6_up_stress
+	atf_add_test_case tap_stress
+	atf_add_test_case tap_up_stress
+	atf_add_test_case tun_ipv6_up_stress
+	atf_add_test_case tun_stress
+	atf_add_test_case tun_up_stress
+	atf_add_test_case vlan_ipv6_up_stress
+	atf_add_test_case vlan_stress
+	atf_add_test_case vlan_up_stress
+	atf_add_test_case vmnet_ipv6_up_stress
+	atf_add_test_case vmnet_stress
+	atf_add_test_case vmnet_up_stress
+}
+
+do_stress()
+{
+	local IFACE
+
+	IFACE=`get_iface $1`
+
+	# First thread: create the interface
+	while true; do
+		ifconfig $IFACE create 2>/dev/null && \
+			echo -n . >> creator_count.txt
+	done &
+	CREATOR_PID=$!
+
+	# Second thread: destroy the lagg
+	while true; do 
+		ifconfig $IFACE destroy 2>/dev/null && \
+			echo -n . >> destroyer_count.txt
+	done &
+	DESTROYER_PID=$!
+
+	sleep ${TESTLEN}
+	kill $CREATOR_PID
+	kill $DESTROYER_PID
+	echo "Created $IFACE `stat -f %z creator_count.txt` times."
+	echo "Destroyed it `stat -f %z destroyer_count.txt` times."
+}
+
+# Implement the up stress tests
+# Parameters
+# $1	Interface class, etc "lo" or "tap"
+# $2	"6" to enable IPv6 auto address assignment, anything else otherwise
+# $3	p2p for point to point interfaces, anything else for normal interfaces
+do_up_stress()
+{
+	local IFACE IPv6 MAC P2P SRCDIR
+
+	# Configure the interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	DSTADDR="192.0.2.3"
+	MASK="24"
+	# ifconfig takes about 10ms to run.  To increase race coverage,
+	# randomly delay the two commands relative to each other by 5ms either
+	# way.
+	MEAN_SLEEP_SECONDS=.005
+	MAX_SLEEP_USECS=10000
+
+	IFACE=`get_iface $1`
+	IPV6=$2
+	P2P=$3
+
+	SRCDIR=$( atf_get_srcdir )
+	if [ "$IPV6" = 6 ]; then
+		ipv6_cmd="true"
+	else
+		ipv6_cmd="ifconfig $IFACE inet6 ifdisabled"
+	fi
+	if [ "$P2P" = "p2p" ]; then
+		up_cmd="ifconfig $IFACE up ${ADDR}/${MASK} ${DSTADDR}"
+	else
+		up_cmd="ifconfig $IFACE up ${ADDR}/${MASK}"
+	fi
+	while true; do
+		eval "$ipv6_cmd"
+		{ sleep ${MEAN_SLEEP_SECONDS} && \
+			eval "$up_cmd" 2> /dev/null &&
+			echo -n . >> up_count.txt ; } &
+		{ ${SRCDIR}/randsleep ${MAX_SLEEP_USECS} && \
+			ifconfig $IFACE destroy &&
+			echo -n . >> destroy_count.txt ; } &
+		wait
+		ifconfig $IFACE create
+	done &
+	LOOP_PID=$!
+
+	sleep ${TESTLEN}
+	kill $LOOP_PID
+	echo "Upped ${IFACE} `stat -f %z up_count.txt` times."
+	echo "Destroyed it `stat -f %z destroy_count.txt` times."
+}
+
+# Creates a new cloned interface, registers it for cleanup, and echoes it
+# params: $1	Interface class name (tap, gif, etc)
+get_iface()
+{
+	local CLASS DEV N
+
+	CLASS=$1
+	N=0
+	while ! ifconfig ${CLASS}${N} create > /dev/null 2>&1; do
+		if [ "$N" -ge 8 ]; then
+			atf_skip "Could not create a ${CLASS} interface"
+		else
+			N=$(($N + 1))
+		fi
+	done
+	local DEV=${CLASS}${N}
+	# Record the device so we can clean it up later
+	echo ${DEV} >> "devices_to_cleanup"
+	echo ${DEV}
+}
+
+
+cleanup_ifaces()
+{
+	local DEV
+
+	for DEV in `cat "devices_to_cleanup"`; do
+		if [ ${DEV%%[0-9]*a} = "epair" ]; then
+			ifconfig ${DEV}a destroy
+		else
+			ifconfig ${DEV} destroy
+		fi
+	done
+	true
+}
diff --git a/tests/sys/net/if_lagg_test.sh b/tests/sys/net/if_lagg_test.sh
new file mode 100755
index 000000000000..9d85b5d40bac
--- /dev/null
+++ b/tests/sys/net/if_lagg_test.sh
@@ -0,0 +1,466 @@
+#
+#  Copyright (c) 2014 Spectra Logic Corporation
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions
+#  are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions, and the following disclaimer,
+#     without modification.
+#  2. Redistributions in binary form must reproduce at minimum a disclaimer
+#     substantially similar to the "NO WARRANTY" disclaimer below
+#     ("Disclaimer") and any redistribution must be conditioned upon
+#     including a substantially similar Disclaimer requirement for further
+#     binary redistribution.
+#
+#  NO WARRANTY
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+#  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#  HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+#  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+#  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+#  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+#  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+#  IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGES.
+#
+#  Authors: Alan Somers         (Spectra Logic Corporation)
+#
+# $FreeBSD$
+
+atf_test_case create cleanup
+create_head()
+{
+	atf_set "descr" "Create a lagg and assign an address"
+	atf_set "require.user" "root"
+}
+create_body()
+{
+	local TAP0 TAP1 LAGG MAC
+
+	# Configure the lagg interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	MASK="24"
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	LAGG=`get_lagg`
+
+	# Create the lagg
+	ifconfig $TAP0 up
+	ifconfig $TAP1 up
+	atf_check ifconfig $LAGG up laggport $TAP0 laggport $TAP1 \
+		${ADDR}/${MASK}
+	atf_check -o match:"inet ${ADDR}" ifconfig $LAGG
+	atf_check -o match:"laggport: ${TAP0}" ifconfig $LAGG
+	atf_check -o match:"laggport: ${TAP1}" ifconfig $LAGG
+
+	# Check that all members have the same MAC
+	MAC=`ifconfig $LAGG | awk '/ether/ {print $2}'`
+	atf_check -o match:"ether ${MAC}" ifconfig $TAP0
+	atf_check -o match:"ether ${MAC}" ifconfig $TAP1
+
+	# Check that no members have an IPv6 link-local address. IPv6
+	# link-local addresses should never be merged in any way to prevent
+	# scope violation.
+	atf_check -o not-match:"inet6 fe80:" ifconfig $TAP0
+	atf_check -o not-match:"inet6 fe80:" ifconfig $TAP1
+}
+create_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+atf_test_case status_stress cleanup
+status_stress_head()
+{
+	atf_set "descr" "Simultaneously query a lagg while also creating or destroying it."
+	atf_set "require.user" "root"
+}
+status_stress_body()
+{
+	local TAP0 TAP1 LAGG MAC
+
+	# Configure the lagg interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	MASK="24"
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	TAP2=`get_tap`
+	TAP3=`get_tap`
+	LAGG=`get_lagg`
+
+	# Up the lagg's children
+	ifconfig $TAP0 inet6 ifdisabled up
+	ifconfig $TAP1 inet6 ifdisabled up
+	ifconfig $TAP2 inet6 ifdisabled up
+	ifconfig $TAP3 inet6 ifdisabled up
+
+	# First thread: create and destroy the lagg
+	while true; do
+		ifconfig $LAGG destroy 2>&1
+		ifconfig $LAGG create 2>/dev/null
+		ifconfig $LAGG inet6 ifdisabled
+		ifconfig $LAGG up laggport $TAP0 laggport $TAP1 laggport $TAP2\
+			laggport $TAP3 ${ADDR}/${MASK} 2>/dev/null
+		echo -n . >> creator_count.txt
+	done &
+	CREATOR_PID=$!
+
+	# Second thread: Query the lagg's status
+	while true; do
+		ifconfig -am 2> /dev/null > /dev/null
+		echo -n . >> querier_count.txt
+	done &
+	QUERIER_PID=$!
+
+	sleep 60
+	kill $CREATOR_PID
+	kill $QUERIER_PID
+	echo "Created the lagg `stat -f %z creator_count.txt` times."
+	echo "Queried its status `stat -f %z querier_count.txt` times"
+}
+status_stress_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+atf_test_case create_destroy_stress cleanup
+create_destroy_stress_head()
+{
+	atf_set "descr" "Simultaneously create and destroy a lagg"
+	atf_set "require.user" "root"
+}
+create_destroy_stress_body()
+{
+	local TAP0 TAP1 LAGG MAC
+	
+	atf_skip "Skipping this test because it easily panics the machine"
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	TAP2=`get_tap`
+	TAP3=`get_tap`
+	LAGG=`get_lagg`
+
+	# Up the lagg's children
+	ifconfig $TAP0 inet6 ifdisabled up
+	ifconfig $TAP1 inet6 ifdisabled up
+	ifconfig $TAP2 inet6 ifdisabled up
+	ifconfig $TAP3 inet6 ifdisabled up
+
+	# First thread: create the lagg
+	while true; do
+		ifconfig $LAGG create 2>/dev/null && \
+			echo -n . >> creator_count.txt
+	done &
+	CREATOR_PID=$!
+
+	# Second thread: destroy the lagg
+	while true; do 
+		ifconfig $LAGG destroy 2>/dev/null && \
+			echo -n . >> destroyer_count.txt
+	done &
+	DESTROYER_PID=$!
+
+	sleep 60
+	kill $CREATOR_PID
+	kill $DESTROYER_PID
+	echo "Created the lagg `stat -f %z creator_count.txt` times."
+	echo "Destroyed it `stat -f %z destroyer_count.txt` times."
+}
+create_destroy_stress_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+# This test regresses a panic that is particular to LACP.  If the child's link
+# state changes while the lagg is being destroyed, lacp_linkstate can
+# use-after-free.  The problem is compounded by two factors:
+# 1) In SpectraBSD, downing the parent will also down the child
+# 2) The cxgbe driver will show the link state as "no carrier" as soon as you
+#    down the interface.
+# TeamTrack: P2_30328
+atf_test_case lacp_linkstate_destroy_stress cleanup
+lacp_linkstate_destroy_stress_head()
+{
+	atf_set "descr" "Simultaneously destroy an LACP lagg and change its childrens link states"
+	atf_set "require.user" "root"
+}
+lacp_linkstate_destroy_stress_body()
+{
+	local TAP0 TAP1 LAGG MAC SRCDIR
+	
+	# Configure the lagg interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	MASK="24"
+	# ifconfig takes about 10ms to run.  To increase race coverage,
+	# randomly delay the two commands relative to each other by 5ms either
+	# way.
+	MEAN_SLEEP_SECONDS=.005
+	MAX_SLEEP_USECS=10000
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	LAGG=`get_lagg`
+
+	# Up the lagg's children
+	ifconfig $TAP0 inet6 ifdisabled up
+	ifconfig $TAP1 inet6 ifdisabled up
+
+	SRCDIR=$( atf_get_srcdir )
+	while true; do
+		ifconfig $LAGG inet6 ifdisabled
+		# We must open the tap devices to change their link states
+		cat /dev/$TAP0 > /dev/null &
+		CAT0_PID=$!
+		cat /dev/$TAP1 > /dev/null &
+		CAT1_PID=$!
+		ifconfig $LAGG up laggport $TAP0 laggport $TAP1 \
+			${ADDR}/${MASK} 2> /dev/null &&
+		{ sleep ${MEAN_SLEEP_SECONDS} && \
+			kill $CAT0_PID &&
+			kill $CAT1_PID &&
+			echo -n . >> linkstate_count.txt ; } &
+		{ ${SRCDIR}/randsleep ${MAX_SLEEP_USECS} && \
+			ifconfig $LAGG destroy &&
+			echo -n . >> destroy_count.txt ; } &
+		wait
+		ifconfig $LAGG create
+	done &
+	LOOP_PID=$!
+
+	sleep 60
+	kill $LOOP_PID
+	echo "Disconnected the children `stat -f %z linkstate_count.txt` times."
+	echo "Destroyed the lagg `stat -f %z destroy_count.txt` times."
+}
+lacp_linkstate_destroy_stress_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+atf_test_case up_destroy_stress cleanup
+up_destroy_stress_head()
+{
+	atf_set "descr" "Simultaneously up and destroy a lagg"
+	atf_set "require.user" "root"
+}
+up_destroy_stress_body()
+{
+	local TAP0 TAP1 LAGG MAC SRCDIR
+
+	atf_skip "Skipping this test because it panics the machine fairly often"
+	
+	# Configure the lagg interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	MASK="24"
+	# ifconfig takes about 10ms to run.  To increase race coverage,
+	# randomly delay the two commands relative to each other by 5ms either
+	# way.
+	MEAN_SLEEP_SECONDS=.005
+	MAX_SLEEP_USECS=10000
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	TAP2=`get_tap`
+	TAP3=`get_tap`
+	LAGG=`get_lagg`
+
+	# Up the lagg's children
+	ifconfig $TAP0 inet6 ifdisabled up
+	ifconfig $TAP1 inet6 ifdisabled up
+	ifconfig $TAP2 inet6 ifdisabled up
+	ifconfig $TAP3 inet6 ifdisabled up
+
+	SRCDIR=$( atf_get_srcdir )
+	while true; do
+		ifconfig $LAGG inet6 ifdisabled
+		{ sleep ${MEAN_SLEEP_SECONDS} && \
+			ifconfig $LAGG up laggport $TAP0 laggport $TAP1 \
+				laggport $TAP2 laggport $TAP3 \
+				${ADDR}/${MASK} 2> /dev/null &&
+			echo -n . >> up_count.txt ; } &
+		{ ${SRCDIR}/randsleep ${MAX_SLEEP_USECS} && \
+			ifconfig $LAGG destroy &&
+			echo -n . >> destroy_count.txt ; } &
+		wait
+		ifconfig $LAGG create
+	done &
+	LOOP_PID=$!
+
+	sleep 60
+	kill $LOOP_PID
+	echo "Upped the lagg `stat -f %z up_count.txt` times."
+	echo "Destroyed it `stat -f %z destroy_count.txt` times."
+}
+up_destroy_stress_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+atf_test_case set_ether cleanup
+set_ether_head()
+{
+	atf_set "descr" "Set a lagg's ethernet address"
+	atf_set "require.user" "root"
+}
+set_ether_body()
+{
+	local TAP0 TAP1 LAGG MAC
+
+	# Configure the lagg interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	MASK="24"
+	MAC="00:11:22:33:44:55"
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	LAGG=`get_lagg`
+
+	# Create the lagg
+	ifconfig $TAP0 up
+	ifconfig $TAP1 up
+	atf_check ifconfig $LAGG up laggport $TAP0 laggport $TAP1 \
+		${ADDR}/${MASK}
+
+	# Change the lagg's ethernet address
+	atf_check ifconfig $LAGG ether ${MAC}
+
+	# Check that all members have the same MAC
+	atf_check -o match:"ether ${MAC}" ifconfig $LAGG
+	atf_check -o match:"ether ${MAC}" ifconfig $TAP0
+	atf_check -o match:"ether ${MAC}" ifconfig $TAP1
+}
+set_ether_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+atf_test_case updown cleanup
+updown_head()
+{
+	atf_set "descr" "upping or downing a lagg ups or downs its children"
+	atf_set "require.user" "root"
+}
+updown_body()
+{
+	local TAP0 TAP1 LAGG MAC
+
+	atf_expect_fail "PR 226144 Upping a lagg interrface should automatically up its children"
+	# Configure the lagg interface to use an RFC5737 nonrouteable addresses
+	ADDR="192.0.2.2"
+	MASK="24"
+	MAC="00:11:22:33:44:55"
+
+	TAP0=`get_tap`
+	TAP1=`get_tap`
+	LAGG=`get_lagg`
+
+	# Create the lagg
+	ifconfig $TAP0 up
+	ifconfig $TAP1 up
+	atf_check ifconfig $LAGG up laggport $TAP0 laggport $TAP1 \
+		${ADDR}/${MASK}
+
+	# Down the lagg
+	ifconfig $LAGG down
+	atf_check -o not-match:"flags=.*\<UP\>" ifconfig $LAGG
+	atf_check -o not-match:"flags=.*\<UP\>" ifconfig $TAP0
+	atf_check -o not-match:"flags=.*\<UP\>" ifconfig $TAP1
+	# Up the lagg again
+	ifconfig $LAGG up
+	atf_check -o match:"flags=.*\<UP\>" ifconfig $LAGG
+	atf_check -o match:"flags=.*\<UP\>" ifconfig $TAP0
+	atf_check -o match:"flags=.*\<UP\>" ifconfig $TAP1
+
+	# Check that no members have acquired an IPv6 link-local address by
+	# virtue of being upped. IPv6 link-local addresses should never be
+	# merged in any way to prevent scope violation.
+	atf_check -o not-match:"inet6 fe80:" ifconfig $TAP0
+	atf_check -o not-match:"inet6 fe80:" ifconfig $TAP1
+}
+updown_cleanup()
+{
+	cleanup_tap_and_lagg
+}
+
+# Check for lock-order reversals.  For best results, this test should be run
+# last.
+atf_test_case witness
+witness_head()
+{
+	atf_set "descr" "Check witness(4) for lock-order reversals in if_lagg"
+}
+witness_body()
+{
+	if [ `sysctl -n debug.witness.watch` -ne 1 ]; then
+		atf_skip "witness(4) is not enabled"
+	fi
+	if `sysctl -n debug.witness.badstacks | grep -q 'at lagg_'`; then
+		sysctl debug.witness.badstacks
+		atf_fail "Lock-order reversals involving if_lagg.c detected"
+	fi
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case create
+	atf_add_test_case create_destroy_stress
+	atf_add_test_case lacp_linkstate_destroy_stress
+	atf_add_test_case set_ether
+	atf_add_test_case status_stress
+	atf_add_test_case up_destroy_stress
+	atf_add_test_case updown
+	# For best results, keep the witness test last
+	atf_add_test_case witness
+}
+
+
+# Creates a new tap(4) interface, registers it for cleanup, and echoes it
+get_tap()
+{
+	local TAPN=0
+	while ! ifconfig tap${TAPN} create > /dev/null 2>&1; do
+		if [ "$TAPN" -ge 8 ]; then
+			atf_skip "Could not create a tap(4) interface"
+		else
+			TAPN=$(($TAPN + 1))
+		fi
+	done
+	local TAPD=tap${TAPN}
+	# Record the TAP device so we can clean it up later
+	echo ${TAPD} >> "devices_to_cleanup"
+	echo ${TAPD}
+}
+
+# Creates a new lagg(4) interface, registers it for cleanup, and echoes it
+get_lagg()
+{
+	local LAGGN=0
+	while ! ifconfig lagg${LAGGN} create > /dev/null 2>&1; do
+		if [ "$LAGGN" -ge 8 ]; then
+			atf_skip "Could not create a lagg(4) interface"
+		else
+			LAGGN=$(($LAGGN + 1))
+		fi
+	done
+	local LAGGD=lagg${LAGGN}
+	# Record the lagg device so we can clean it up later
+	echo ${LAGGD} >> "devices_to_cleanup"
+	echo ${LAGGD}
+}
+
+cleanup_tap_and_lagg()
+{
+	local DEV
+
+	for DEV in `cat "devices_to_cleanup"`; do
+		ifconfig ${DEV} destroy
+	done
+	true
+}
diff --git a/tests/sys/net/randsleep.c b/tests/sys/net/randsleep.c
new file mode 100644
index 000000000000..a602d06921e7
--- /dev/null
+++ b/tests/sys/net/randsleep.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2014 Spectra Logic Corporation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ *
+ * Authors: Alan Somers         (Spectra Logic Corporation)
+ *
+ * $FreeBSD$
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define RANDOM_MAX ((1<<31) - 1)
+
+int main(int argc, char** argv){
+	useconds_t max_usecs, usecs;
+	double frac;
+
+	if (argc != 2) {
+		printf("Usage: randsleep <max_microseconds>\n");
+		exit(2);
+	}
+
+	errno = 0;
+	max_usecs = (useconds_t)strtol(argv[1], NULL, 0);
+	if (errno != 0) {
+		perror("strtol");
+		exit(1);
+	}
+	srandomdev();
+	frac = (double)random() / (double)RANDOM_MAX;
+	usecs = (useconds_t)((double)max_usecs * frac);
+	usleep(usecs);
+
+	return (0);
+}