From: Arnd Bergmann <arnd@xxxxxxxx> Clang warns about excessive stack usage on 32-bit targets: drivers/net/ethernet/mellanox/mlx5/core/en_main.c:3597:12: error: stack frame size (1184) exceeds limit (1024) in 'mlx5e_setup_tc' [-Werror,-Wframe-larger-than] static int mlx5e_setup_tc(struct net_device *dev, enum tc_setup_type type, It turns out that both the mlx5e_setup_tc_mqprio_dcb() function and the mlx5e_safe_switch_params() function it calls have a copy of 'struct mlx5e_params' on the stack, and this structure is fairly large. Use dynamic allocation for both. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- .../net/ethernet/mellanox/mlx5/core/en_main.c | 36 ++++++++++++------- 1 file changed, 23 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 6bb0fdaa5efa..e5198c26e383 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -2993,37 +2993,42 @@ static int mlx5e_switch_priv_channels(struct mlx5e_priv *priv, return err; } -int mlx5e_safe_switch_params(struct mlx5e_priv *priv, +noinline_for_stack int mlx5e_safe_switch_params(struct mlx5e_priv *priv, struct mlx5e_params *params, mlx5e_fp_preactivate preactivate, void *context, bool reset) { - struct mlx5e_channels new_chs = {}; + struct mlx5e_channels *new_chs; int err; reset &= test_bit(MLX5E_STATE_OPENED, &priv->state); if (!reset) return mlx5e_switch_priv_params(priv, params, preactivate, context); - new_chs.params = *params; + new_chs = kzalloc(sizeof(*new_chs), GFP_KERNEL); + if (!new_chs) + return -ENOMEM; + new_chs->params = *params; - mlx5e_selq_prepare_params(&priv->selq, &new_chs.params); + mlx5e_selq_prepare_params(&priv->selq, &new_chs->params); - err = mlx5e_open_channels(priv, &new_chs); + err = mlx5e_open_channels(priv, new_chs); if (err) goto err_cancel_selq; - err = mlx5e_switch_priv_channels(priv, &new_chs, preactivate, context); + err = mlx5e_switch_priv_channels(priv, new_chs, preactivate, context); if (err) goto err_close; + kfree(new_chs); return 0; err_close: - mlx5e_close_channels(&new_chs); + mlx5e_close_channels(new_chs); err_cancel_selq: mlx5e_selq_cancel(&priv->selq); + kfree(new_chs); return err; } @@ -3419,10 +3424,10 @@ static void mlx5e_params_mqprio_reset(struct mlx5e_params *params) mlx5e_params_mqprio_dcb_set(params, 1); } -static int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_priv *priv, +static noinline_for_stack int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_priv *priv, struct tc_mqprio_qopt *mqprio) { - struct mlx5e_params new_params; + struct mlx5e_params *new_params; u8 tc = mqprio->num_tc; int err; @@ -3431,10 +3436,13 @@ static int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_priv *priv, if (tc && tc != MLX5E_MAX_NUM_TC) return -EINVAL; - new_params = priv->channels.params; - mlx5e_params_mqprio_dcb_set(&new_params, tc ? tc : 1); + new_params = kmemdup(&priv->channels.params, + sizeof(priv->channels.params), GFP_KERNEL); + if (!new_params) + return -ENOMEM; + mlx5e_params_mqprio_dcb_set(new_params, tc ? tc : 1); - err = mlx5e_safe_switch_params(priv, &new_params, + err = mlx5e_safe_switch_params(priv, new_params, mlx5e_num_channels_changed_ctx, NULL, true); if (!err && priv->mqprio_rl) { @@ -3445,6 +3453,8 @@ static int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_priv *priv, priv->max_opened_tc = max_t(u8, priv->max_opened_tc, mlx5e_get_dcb_num_tc(&priv->channels.params)); + + kfree(new_params); return err; } @@ -3533,7 +3543,7 @@ static struct mlx5e_mqprio_rl *mlx5e_mqprio_rl_create(struct mlx5_core_dev *mdev return rl; } -static int mlx5e_setup_tc_mqprio_channel(struct mlx5e_priv *priv, +static noinline_for_stack int mlx5e_setup_tc_mqprio_channel(struct mlx5e_priv *priv, struct tc_mqprio_qopt_offload *mqprio) { mlx5e_fp_preactivate preactivate; -- 2.39.0