From: Lama Kayal In mlx5_esw_vport_disable(), move esw_apply_vport_rx_mode() ahead of esw_vport_change_handle_locked() so vport->allmulti_rule is NULL before the change handler observes it. During FW-fatal recovery the disable runs while dev->state == INTERNAL_ERROR. The promisc query inside esw_update_vport_rx_mode() fails and returns early, leaving vport->allmulti_rule intact, so esw_update_vport_mc_promisc() runs and adds MLX5_ACTION_ADD entries to vport->mc_list whose flow rules are then installed in the FDB by esw_add_mc_addr(). esw_destroy_legacy_table() tears down the FDB with those refs still held, corrupting the sub-tree and leaving dangling flow_rule pointers in vport->mc_list. Two-stage failure on `echo 1 > /sys/bus/pci/devices//reset`: refcount_t: underflow; use-after-free. tree_put_node+0xef/0x110 [mlx5_core] clean_tree+0x44/0xd0 [mlx5_core] (x5) mlx5_fs_core_cleanup+0x57/0x1c0 [mlx5_core] mlx5_unload+0x65/0xd0 [mlx5_core] ... mlx5_health_try_recover BUG: unable to handle page fault for address: 0000000003000055 down_write+0x1c/0x60 mlx5_del_flow_rules+0x33/0x1f0 [mlx5_core] esw_del_mc_addr+0x7b/0x170 [mlx5_core] esw_apply_vport_addr_list+0x56/0xf0 [mlx5_core] esw_vport_change_handle_locked+0x28b/0x310 [mlx5_core] mlx5_esw_vport_enable+0x270/0x4a0 [mlx5_core] ... mlx5_load ... mlx5_health_try_recover esw_apply_vport_rx_mode(false, false) clears vport->allmulti_rule via its local state machine even when the FW del fails. With the rule NULL the !IS_ERR_OR_NULL(allmulti_rule) gate in the change handler closes, no rules are installed during disable, and the reload starts with a clean mc_list. Fixes: 922f56e9a795 ("net/mlx5: Fix steering rules cleanup") Signed-off-by: Lama Kayal Reviewed-by: Cosmin Ratiu Signed-off-by: Tariq Toukan --- drivers/net/ethernet/mellanox/mlx5/core/eswitch.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c index b6e2c153b4f7..4c7fa4a52b0e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c @@ -1040,13 +1040,19 @@ void mlx5_esw_vport_disable(struct mlx5_eswitch *esw, struct mlx5_vport *vport) (vport->info.ipsec_crypto_enabled || vport->info.ipsec_packet_enabled)) esw->enabled_ipsec_vf_count--; + /* Clear rx-mode before esw_vport_change_handle_locked(): on + * MLX5_VPORT_PROMISC_CHANGE it calls esw_update_vport_mc_promisc() + * when vport->allmulti_rule is set, repopulating mc_list with FDB + * rules that dangle once the FDB is destroyed. NULL allmulti_rule + * here skips that path. + */ + esw_apply_vport_rx_mode(esw, vport, false, false); /* We don't assume VFs will cleanup after themselves. * Calling vport change handler while vport is disabled will cleanup * the vport resources. */ esw_vport_change_handle_locked(vport); vport->enabled_events = 0; - esw_apply_vport_rx_mode(esw, vport, false, false); esw_vport_cleanup(esw, vport); esw->enabled_vports--; -- 2.44.0