From: Petr Machata petrm@mellanox.com
[ Upstream commit dedfde2fe1c4ccf27179fcb234e2112d065c39bb ]
Spectrum systems use DSCP rewrite map to update DSCP field in egressing packets to correspond to priority that the packet has. Whether rewriting will take place is determined at the point when the packet ingresses the switch: if the port is in Trust L3 mode, packet priority is determined from the DSCP map at the port, and DSCP rewrite will happen. If the port is in Trust L2 mode, 802.1p is used for packet prioritization, and no DSCP rewrite will happen.
The driver determines the port trust mode based on whether any DSCP prioritization rules are in effect at given port. If there are any, trust level is L3, otherwise it's L2. When the last DSCP rule is removed, the port is switched to trust L2. Under that scenario, if DSCP of a packet should be rewritten, it should be rewritten to 0.
However, when switching to Trust L2, the driver neglects to also update the DSCP rewrite map. The last DSCP rule thus remains in effect, and packets egressing through this port, if they have the right priority, will have their DSCP set according to this rule.
Fix by first configuring the rewrite map, and only then switching to trust L2 and bailing out.
Fixes: b2b1dab6884e ("mlxsw: spectrum: Support ieee_setapp, ieee_delapp") Signed-off-by: Petr Machata petrm@mellanox.com Reported-by: Alex Veber alexve@mellanox.com Tested-by: Alex Veber alexve@mellanox.com Signed-off-by: Ido Schimmel idosch@mellanox.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/mellanox/mlxsw/spectrum_dcb.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c index b25048c6c761..21296fa7f7fb 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c @@ -408,14 +408,6 @@ static int mlxsw_sp_port_dcb_app_update(struct mlxsw_sp_port *mlxsw_sp_port) have_dscp = mlxsw_sp_port_dcb_app_prio_dscp_map(mlxsw_sp_port, &prio_map);
- if (!have_dscp) { - err = mlxsw_sp_port_dcb_toggle_trust(mlxsw_sp_port, - MLXSW_REG_QPTS_TRUST_STATE_PCP); - if (err) - netdev_err(mlxsw_sp_port->dev, "Couldn't switch to trust L2\n"); - return err; - } - mlxsw_sp_port_dcb_app_dscp_prio_map(mlxsw_sp_port, default_prio, &dscp_map); err = mlxsw_sp_port_dcb_app_update_qpdpm(mlxsw_sp_port, @@ -432,6 +424,14 @@ static int mlxsw_sp_port_dcb_app_update(struct mlxsw_sp_port *mlxsw_sp_port) return err; }
+ if (!have_dscp) { + err = mlxsw_sp_port_dcb_toggle_trust(mlxsw_sp_port, + MLXSW_REG_QPTS_TRUST_STATE_PCP); + if (err) + netdev_err(mlxsw_sp_port->dev, "Couldn't switch to trust L2\n"); + return err; + } + err = mlxsw_sp_port_dcb_toggle_trust(mlxsw_sp_port, MLXSW_REG_QPTS_TRUST_STATE_DSCP); if (err) {