Commit 5d66773f authored by Ido Schimmel's avatar Ido Schimmel Committed by David S. Miller
Browse files

selftests: devlink_trap_l3_drops: Avoid race condition 



The test checks that packets are trapped when they should egress a
router interface (RIF) that has become disabled. This is a temporary
state in a RIF's deletion sequence.

Currently, the test deletes the RIF by flushing all the IP addresses
configured on the associated netdev (br0). However, this is racy, as
this also flushes all the routes pointing to the netdev and if the
routes are deleted from the device before the RIF is disabled, then no
packets will try to egress the disabled RIF and the trap will not be
triggered.

Instead, trigger the deletion of the RIF by unlinking the mlxsw port
from the bridge that is backing the RIF. Unlike before, this will not
cause the kernel to delete the routes pointing to the bridge.

Note that due to current mlxsw locking scheme the RIF is always deleted
first, but this is going to change.

Signed-off-by: default avatarIdo Schimmel <idosch@mellanox.com>
Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ab2b8ab2

tools/testing/selftests/drivers/net/mlxsw/devlink_trap_l3_drops.sh

+3 −8
Original line number Original line Diff line number Diff line
@@ -641,13 +641,9 @@ erif_disabled_test() 
	mz_pid=$!

	mz_pid=$!





	sleep 5

	sleep 5

	# In order to see this trap we need a route that points to disabled RIF.

	# Unlinking the port from the bridge will disable the RIF associated

	# When ipv6 address is flushed, there is a delay and the routes are

	# with br0 as it is no longer an upper of any mlxsw port.

	# deleted before the RIF and we cannot get state that we have route

	ip link set dev $rp1 nomaster

	# to disabled RIF.

	# Delete IPv6 address first and then check this trap with flushing IPv4.

	ip -6 add flush dev br0

	ip -4 add flush dev br0





	t1_packets=$(devlink_trap_rx_packets_get $trap_name)

	t1_packets=$(devlink_trap_rx_packets_get $trap_name)

	t1_bytes=$(devlink_trap_rx_bytes_get $trap_name)

	t1_bytes=$(devlink_trap_rx_bytes_get $trap_name)
@@ -659,7 +655,6 @@ erif_disabled_test() 
	log_test "Egress RIF disabled"

	log_test "Egress RIF disabled"





	kill $mz_pid && wait $mz_pid &> /dev/null

	kill $mz_pid && wait $mz_pid &> /dev/null

	ip link set dev $rp1 nomaster

	__addr_add_del $rp1 add 192.0.2.2/24 2001:db8:1::2/64

	__addr_add_del $rp1 add 192.0.2.2/24 2001:db8:1::2/64

	ip link del dev br0 type bridge

	ip link del dev br0 type bridge

	devlink_trap_action_set $trap_name "drop"

	devlink_trap_action_set $trap_name "drop"