net/mlx5e: reset XPS on error flow if netdev isn't registered yet

BugLink: https://bugs.launchpad.net/bugs/1931896
commit 77ecd10d0a8aaa6e4871d8c63626e4c9fc5e47db upstream.

mlx5e_attach_netdev can be called prior to registering the netdevice:
Example stack:

ipoib_new_child_link ->
ipoib_intf_init->
rdma_init_netdev->
mlx5_rdma_setup_rn->

mlx5e_attach_netdev->
mlx5e_num_channels_changed ->
mlx5e_set_default_xps_cpumasks ->
netif_set_xps_queue ->
__netif_set_xps_queue -> kmalloc

If any later stage fails at any point after mlx5e_num_channels_changed()
returns, XPS allocated maps will never be freed as they
are only freed during netdev unregistration, which will never happen for
yet to be registered netdevs.

Fixes: 3909a12e7913 ("net/mlx5e: Fix configuration of XPS cpumasks and netdev queues in corner cases")
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 7bb189e656283480464cb530c3043a0e1afe6d8e..3b1f8436821674dc49c3526091d83a7b7e4c4e0f 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -5449,6 +5449,11 @@ err_free_netdev:
        return NULL;
 }
 
+static void mlx5e_reset_channels(struct net_device *netdev)
+{
+       netdev_reset_tc(netdev);
+}
+
 int mlx5e_attach_netdev(struct mlx5e_priv *priv)
 {
        const bool take_rtnl = priv->netdev->reg_state == NETREG_REGISTERED;
@@ -5502,6 +5507,7 @@ err_cleanup_tx:
        profile->cleanup_tx(priv);
 
 out:
+       mlx5e_reset_channels(priv->netdev);
        set_bit(MLX5E_STATE_DESTROYING, &priv->state);
        cancel_work_sync(&priv->update_stats_work);
        return err;
@@ -5519,6 +5525,7 @@ void mlx5e_detach_netdev(struct mlx5e_priv *priv)
 
        profile->cleanup_rx(priv);
        profile->cleanup_tx(priv);
+       mlx5e_reset_channels(priv->netdev);
        cancel_work_sync(&priv->update_stats_work);
 }