From: Yael Chemla When the channel count changes and the RQT size changes with it, a problem arise for non-default RSS contexts. The driver-side indirection table grows actual_table_size without filling the new entries; stale entries from a prior larger configuration may be re-exposed, causing mlx5e_calc_indir_rqns() to WARN on an out-of-range index. Replace mlx5e_rss_params_indir_modify_actual_size() with mlx5e_rss_ctx_resize(), which fills new entries by replicating the existing pattern, matching what ethtool_rxfh_ctxs_resize() does for the same case. And restrict the loop to non-default contexts. Call ethtool_rxfh_ctxs_can_resize() before acquiring state_lock to validate that all non-default contexts can be resized, and ethtool_rxfh_ctxs_resize() after releasing it to fold or unfold their indirection tables. Both functions acquire rss_lock internally and cannot be called under state_lock. RTNL, held by all set_channels callers, serialises context creation and deletion making the pre-lock check safe. Guard both ethtool calls on mlx5e_rx_res_rss_cnt() > 1: skip the validation and resize when no non-default contexts exist. This naturally covers representors and IPoIB, which share mlx5e_ethtool_set_channels() but cannot have non-default RSS contexts. Signed-off-by: Yael Chemla Reviewed-by: Nimrod Oren Signed-off-by: Tariq Toukan --- .../net/ethernet/mellanox/mlx5/core/en/rss.c | 16 +++++++-- .../net/ethernet/mellanox/mlx5/core/en/rss.h | 3 +- .../ethernet/mellanox/mlx5/core/en/rx_res.c | 15 ++++++-- .../ethernet/mellanox/mlx5/core/en_ethtool.c | 35 +++++++++++++++++-- 4 files changed, 60 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rss.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rss.c index a2ec67a122d9..992a78580a40 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rss.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rss.c @@ -85,9 +85,21 @@ bool mlx5e_rss_get_inner_ft_support(struct mlx5e_rss *rss) return rss->params.inner_ft_support; } -void mlx5e_rss_params_indir_modify_actual_size(struct mlx5e_rss *rss, u32 num_channels) +void mlx5e_rss_set_indir_actual_size(struct mlx5e_rss *rss, u32 size) { - rss->indir.actual_table_size = mlx5e_rqt_size(rss->mdev, num_channels); + rss->indir.actual_table_size = size; +} + +/* Handles non-default contexts, replicate existing pattern into new entries, + * matching what ethtool_rxfh_ctxs_resize() does. + */ +void mlx5e_rss_ctx_resize(struct mlx5e_rss *rss, u32 new_size) +{ + u32 old_size = rss->indir.actual_table_size; + u32 i; + + for (i = old_size; i < new_size; i++) + rss->indir.table[i] = rss->indir.table[i % old_size]; } int mlx5e_rss_params_indir_init(struct mlx5e_rss_params_indir *indir, diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rss.h b/drivers/net/ethernet/mellanox/mlx5/core/en/rss.h index 17664757a561..e48070e02979 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rss.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rss.h @@ -34,7 +34,7 @@ struct mlx5e_rss; int mlx5e_rss_params_indir_init(struct mlx5e_rss_params_indir *indir, u32 actual_table_size, u32 max_table_size); void mlx5e_rss_params_indir_cleanup(struct mlx5e_rss_params_indir *indir); -void mlx5e_rss_params_indir_modify_actual_size(struct mlx5e_rss *rss, u32 num_channels); +void mlx5e_rss_ctx_resize(struct mlx5e_rss *rss, u32 new_size); struct mlx5e_rss * mlx5e_rss_init(struct mlx5_core_dev *mdev, const struct mlx5e_rss_params *params, @@ -46,6 +46,7 @@ void mlx5e_rss_refcnt_dec(struct mlx5e_rss *rss); unsigned int mlx5e_rss_refcnt_read(struct mlx5e_rss *rss); bool mlx5e_rss_get_inner_ft_support(struct mlx5e_rss *rss); +void mlx5e_rss_set_indir_actual_size(struct mlx5e_rss *rss, u32 size); u32 mlx5e_rss_get_tirn(struct mlx5e_rss *rss, enum mlx5_traffic_types tt, bool inner); bool mlx5e_rss_valid_tir(struct mlx5e_rss *rss, enum mlx5_traffic_types tt, bool inner); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rx_res.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rx_res.c index 92974b11ec75..d81a91eb7664 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rx_res.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rx_res.c @@ -42,11 +42,20 @@ static u32 *get_vhca_ids(struct mlx5e_rx_res *res, int offset) void mlx5e_rx_res_rss_update_num_channels(struct mlx5e_rx_res *res, u32 nch) { + u32 new_size = mlx5e_rqt_size(res->mdev, nch); int i; - for (i = 0; i < MLX5E_MAX_NUM_RSS; i++) { - if (res->rss[i]) - mlx5e_rss_params_indir_modify_actual_size(res->rss[i], nch); + WARN_ON_ONCE(res->rss_active); + + /* Default context */ + mlx5e_rss_set_indir_actual_size(res->rss[0], new_size); + + /* Non-default contexts */ + for (i = 1; i < MLX5E_MAX_NUM_RSS; i++) { + if (res->rss[i]) { + mlx5e_rss_ctx_resize(res->rss[i], new_size); + mlx5e_rss_set_indir_actual_size(res->rss[i], new_size); + } } } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c index c483008e33e9..4462cf29e977 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c @@ -499,11 +499,15 @@ int mlx5e_ethtool_set_channels(struct mlx5e_priv *priv, { struct mlx5e_params *cur_params = &priv->channels.params; unsigned int count = ch->combined_count; + int new_rqt_size, cur_rqt_size; struct mlx5e_params new_params; bool arfs_enabled; + bool has_rss_ctxs; bool opened; int err = 0; + ASSERT_RTNL(); + if (!count) { netdev_info(priv->netdev, "%s: combined_count=0 not supported\n", __func__); @@ -513,16 +517,33 @@ int mlx5e_ethtool_set_channels(struct mlx5e_priv *priv, if (cur_params->num_channels == count) return 0; + new_rqt_size = mlx5e_rqt_size(priv->mdev, count); + /* Validate that all non-default RSS contexts can be resized before + * committing to the channel count change. + * ethtool_rxfh_ctxs_can_resize() acquires rss_lock internally and + * cannot be called under state_lock (rss_lock -> state_lock ordering). + */ + has_rss_ctxs = priv->rx_res && mlx5e_rx_res_rss_cnt(priv->rx_res) > 1; + if (has_rss_ctxs) { + err = ethtool_rxfh_ctxs_can_resize(priv->netdev, new_rqt_size); + if (err) + return err; + } + mutex_lock(&priv->state_lock); + if (!priv->rx_res) { + err = -EINVAL; + goto out; + } + + cur_rqt_size = mlx5e_rqt_size(priv->mdev, cur_params->num_channels); + /* If RXFH is configured, changing the channels number is allowed only if * it does not require resizing the RSS table. This is because the previous * configuration may no longer be compatible with the new RSS table. */ if (netif_is_rxfh_configured(priv->netdev)) { - int cur_rqt_size = mlx5e_rqt_size(priv->mdev, cur_params->num_channels); - int new_rqt_size = mlx5e_rqt_size(priv->mdev, count); - if (new_rqt_size != cur_rqt_size) { err = -EINVAL; netdev_err(priv->netdev, @@ -577,6 +598,14 @@ int mlx5e_ethtool_set_channels(struct mlx5e_priv *priv, out: mutex_unlock(&priv->state_lock); + /* After a successful channel count change that altered the RQT size, + * fold or unfold the indirection tables of all non-default RSS + * contexts. Must run after state_lock is released because + * ethtool_rxfh_ctxs_resize() acquires rss_lock internally. + */ + if (!err && cur_rqt_size != new_rqt_size && has_rss_ctxs) + ethtool_rxfh_ctxs_resize(priv->netdev, new_rqt_size); + return err; } -- 2.44.0