[PATCH 4.10 011/111] net/mlx5: E-Switch, Dont allow changing inline mode when flows are configured

From: Greg Kroah-Hartman
Date: Tue Mar 28 2017 - 09:40:10 EST


4.10-stable review patch. If anyone has any objections, please let me know.

------------------

From: Roi Dayan <roid@xxxxxxxxxxxx>


[ Upstream commit 375f51e2b5b7b9a42b3139aea519cbb1bfc5d6ef ]

Changing the eswitch inline mode can potentially cause already configured
flows not to match the policy. E.g. set policy L4, add some L4 rules,
set policy to L2 --> bad! Hence we disallow it.

Keep track of how many offloaded rules are now set and refuse
inline mode changes if this isn't zero.

Fixes: bffaa916588e ("net/mlx5: E-Switch, Add control for inline mode")
Signed-off-by: Roi Dayan <roid@xxxxxxxxxxxx>
Reviewed-by: Or Gerlitz <ogerlitz@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/eswitch.h | 1 +
drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c | 8 ++++++++
2 files changed, 9 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
@@ -201,6 +201,7 @@ struct mlx5_esw_offload {
struct mlx5_eswitch_rep *vport_reps;
DECLARE_HASHTABLE(encap_tbl, 8);
u8 inline_mode;
+ u64 num_flows;
};

struct mlx5_eswitch {
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -93,6 +93,8 @@ mlx5_eswitch_add_offloaded_rule(struct m
spec, &flow_act, dest, i);
if (IS_ERR(rule))
mlx5_fc_destroy(esw->dev, counter);
+ else
+ esw->offloads.num_flows++;

return rule;
}
@@ -108,6 +110,7 @@ mlx5_eswitch_del_offloaded_rule(struct m
counter = mlx5_flow_rule_counter(rule);
mlx5_del_flow_rules(rule);
mlx5_fc_destroy(esw->dev, counter);
+ esw->offloads.num_flows--;
}
}

@@ -919,6 +922,11 @@ int mlx5_devlink_eswitch_inline_mode_set
MLX5_CAP_INLINE_MODE_VPORT_CONTEXT)
return -EOPNOTSUPP;

+ if (esw->offloads.num_flows > 0) {
+ esw_warn(dev, "Can't set inline mode when flows are configured\n");
+ return -EOPNOTSUPP;
+ }
+
err = esw_inline_mode_from_devlink(mode, &mlx5_mode);
if (err)
goto out;