[PATCH] [net-next] net/mlx5e: xsk: dynamically allocate mlx5e_channel_param

From: Arnd Bergmann
Date: Mon Jul 08 2019 - 08:56:27 EST


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);
+ 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;

@@ -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;
}

--
2.20.0