On 2019-07-08 15:55, Arnd Bergmann wrote:
> The structure is too large to put on the stack, resulting in a
> warning on 32-bit ARM:
>
> drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c:59:5: error: stack frame size of 1344 bytes in function
> 'mlx5e_open_xsk' [-Werror,-Wframe-larger-than=]
>
> Use kzalloc() instead.
>
> Fixes: a038e9794541 ("net/mlx5e: Add XSK zero-copy support")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> .../mellanox/mlx5/core/en/xsk/setup.c | 25 ++++++++++++-------
> 1 file changed, 16 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
> index aaffa6f68dc0..db9bbec68dbf 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
> @@ -60,24 +60,28 @@ int mlx5e_open_xsk(struct mlx5e_priv *priv, struct mlx5e_params *params,
> struct mlx5e_xsk_param *xsk, struct xdp_umem *umem,
> struct mlx5e_channel *c)
> {
> - struct mlx5e_channel_param cparam = {};
> + struct mlx5e_channel_param *cparam;
> struct dim_cq_moder icocq_moder = {};
> int err;
>
> if (!mlx5e_validate_xsk_param(params, xsk, priv->mdev))
> return -EINVAL;
>
> - mlx5e_build_xsk_cparam(priv, params, xsk, &cparam);
> + cparam = kzalloc(sizeof(*cparam), GFP_KERNEL);
Similar code in mlx5e_open_channels (en_main.c) uses kvzalloc. Although
the struct is currently smaller than a page anyway, and there should be
no difference in behavior now, I suggest using the same alloc function
to keep code uniform.
> + if (!cparam)
> + return -ENOMEM;
>
> - err = mlx5e_open_cq(c, params->rx_cq_moderation, &cparam.rx_cq, &c->xskrq.cq);
> + mlx5e_build_xsk_cparam(priv, params, xsk, cparam);
> +
> + err = mlx5e_open_cq(c, params->rx_cq_moderation, &cparam->rx_cq, &c->xskrq.cq);
> if (unlikely(err))
> - return err;
> + goto err_kfree_cparam;
>
> - err = mlx5e_open_rq(c, params, &cparam.rq, xsk, umem, &c->xskrq);
> + err = mlx5e_open_rq(c, params, &cparam->rq, xsk, umem, &c->xskrq);
> if (unlikely(err))
> goto err_close_rx_cq;
>
> - err = mlx5e_open_cq(c, params->tx_cq_moderation, &cparam.tx_cq, &c->xsksq.cq);
> + err = mlx5e_open_cq(c, params->tx_cq_moderation, &cparam->tx_cq, &c->xsksq.cq);
> if (unlikely(err))
> goto err_close_rq;
>
> @@ -87,18 +91,18 @@ int mlx5e_open_xsk(struct mlx5e_priv *priv, struct mlx5e_params *params,
> * is disabled and then reenabled, but the SQ continues receiving CQEs
> * from the old UMEM.
> */
> - err = mlx5e_open_xdpsq(c, params, &cparam.xdp_sq, umem, &c->xsksq, true);
> + err = mlx5e_open_xdpsq(c, params, &cparam->xdp_sq, umem, &c->xsksq, true);
> if (unlikely(err))
> goto err_close_tx_cq;
>
> - err = mlx5e_open_cq(c, icocq_moder, &cparam.icosq_cq, &c->xskicosq.cq);
> + err = mlx5e_open_cq(c, icocq_moder, &cparam->icosq_cq, &c->xskicosq.cq);
> if (unlikely(err))
> goto err_close_sq;
>
> /* Create a dedicated SQ for posting NOPs whenever we need an IRQ to be
> * triggered and NAPI to be called on the correct CPU.
> */
> - err = mlx5e_open_icosq(c, params, &cparam.icosq, &c->xskicosq);
> + err = mlx5e_open_icosq(c, params, &cparam->icosq, &c->xskicosq);
> if (unlikely(err))
> goto err_close_icocq;
>
Here is kfree missing. It's a memory leak in the good path.
Thanks!
> @@ -123,6 +127,9 @@ int mlx5e_open_xsk(struct mlx5e_priv *priv, struct mlx5e_params *params,
> err_close_rx_cq:
> mlx5e_close_cq(&c->xskrq.cq);
>
> +err_kfree_cparam:
> + kfree(cparam);
> +
> return err;
> }
>
>
