Re: [PATCH rdma-next] RDMA/mlx5: Avoid flexible array warning

[Zhu Yanjun <yanjun.zhu@linux.dev>]

在 2025/5/21 13:34, Leon Romanovsky 写道:
> From: Leon Romanovsky <leonro@nvidia.com>
> 
> The following warning is reported by sparse tool:
> drivers/infiniband/hw/mlx5/fs.c:1664:26: warning: array of flexible
> structures
> 
> Avoid it by simply splitting array into two separate structs.
> 
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

In my local host, I can reproduce this problem. And I think that this 
commit can fix this problem.

Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>

Zhu Yanjun

> ---
>   drivers/infiniband/hw/mlx5/fs.c | 58 ++++++++++++---------------------
>   1 file changed, 21 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/infiniband/hw/mlx5/fs.c b/drivers/infiniband/hw/mlx5/fs.c
> index 251246c73b339..1d67f0ce6b59a 100644
> --- a/drivers/infiniband/hw/mlx5/fs.c
> +++ b/drivers/infiniband/hw/mlx5/fs.c
> @@ -1645,11 +1645,6 @@ static struct mlx5_ib_flow_handler *create_flow_rule(struct mlx5_ib_dev *dev,
>   	return _create_flow_rule(dev, ft_prio, flow_attr, dst, 0, NULL);
>   }
>   
> -enum {
> -	LEFTOVERS_MC,
> -	LEFTOVERS_UC,
> -};
> -
>   static struct mlx5_ib_flow_handler *create_leftovers_rule(struct mlx5_ib_dev *dev,
>   							  struct mlx5_ib_flow_prio *ft_prio,
>   							  struct ib_flow_attr *flow_attr,
> @@ -1659,43 +1654,32 @@ static struct mlx5_ib_flow_handler *create_leftovers_rule(struct mlx5_ib_dev *de
>   	struct mlx5_ib_flow_handler *handler = NULL;
>   
>   	static struct {
> -		struct ib_flow_attr	flow_attr;
>   		struct ib_flow_spec_eth eth_flow;
> -	} leftovers_specs[] = {
> -		[LEFTOVERS_MC] = {
> -			.flow_attr = {
> -				.num_of_specs = 1,
> -				.size = sizeof(leftovers_specs[0])
> -			},
> -			.eth_flow = {
> -				.type = IB_FLOW_SPEC_ETH,
> -				.size = sizeof(struct ib_flow_spec_eth),
> -				.mask = {.dst_mac = {0x1} },
> -				.val =  {.dst_mac = {0x1} }
> -			}
> -		},
> -		[LEFTOVERS_UC] = {
> -			.flow_attr = {
> -				.num_of_specs = 1,
> -				.size = sizeof(leftovers_specs[0])
> -			},
> -			.eth_flow = {
> -				.type = IB_FLOW_SPEC_ETH,
> -				.size = sizeof(struct ib_flow_spec_eth),
> -				.mask = {.dst_mac = {0x1} },
> -				.val = {.dst_mac = {} }
> -			}
> -		}
> -	};
> +		struct ib_flow_attr	flow_attr;
> +	} leftovers_wc = { .flow_attr = { .num_of_specs = 1,
> +					  .size = sizeof(leftovers_wc) },
> +			   .eth_flow = {
> +				   .type = IB_FLOW_SPEC_ETH,
> +				   .size = sizeof(struct ib_flow_spec_eth),
> +				   .mask = { .dst_mac = { 0x1 } },
> +				   .val = { .dst_mac = { 0x1 } } } };
>   
> -	handler = create_flow_rule(dev, ft_prio,
> -				   &leftovers_specs[LEFTOVERS_MC].flow_attr,
> -				   dst);
> +	static struct {
> +		struct ib_flow_spec_eth eth_flow;
> +		struct ib_flow_attr	flow_attr;
> +	} leftovers_uc = { .flow_attr = { .num_of_specs = 1,
> +					  .size = sizeof(leftovers_uc) },
> +			   .eth_flow = {
> +				   .type = IB_FLOW_SPEC_ETH,
> +				   .size = sizeof(struct ib_flow_spec_eth),
> +				   .mask = { .dst_mac = { 0x1 } },
> +				   .val = { .dst_mac = {} } } };
> +
> +	handler = create_flow_rule(dev, ft_prio, &leftovers_wc.flow_attr, dst);
>   	if (!IS_ERR(handler) &&
>   	    flow_attr->type == IB_FLOW_ATTR_ALL_DEFAULT) {
>   		handler_ucast = create_flow_rule(dev, ft_prio,
> -						 &leftovers_specs[LEFTOVERS_UC].flow_attr,
> -						 dst);
> +						 &leftovers_uc.flow_attr, dst);
>   		if (IS_ERR(handler_ucast)) {
>   			mlx5_del_flow_rules(handler->rule);
>   			ft_prio->refcount--;