Re: [dpdk-dev] [PATCH] ethdev: fix check of rx configure

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 11/3/2020 1:31 PM, wangyunjian wrote:
> From: Yunjian Wang <wangyunjian@huawei.com>
> 
> Coverity flags that 'rx_conf' variable is used before
> it's checked for NULL. This patch fixes this issue.
> 
> Coverity issue: 363570
> Fixes: 4ff702b5dfa9 ("ethdev: introduce Rx buffer split")
> 
> Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
> ---
>   lib/librte_ethdev/rte_ethdev.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> index b12bb3854d..c74502d45e 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c
> @@ -1978,16 +1978,17 @@ rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
>   			return -EINVAL;
>   		}
>   	} else {
> -		const struct rte_eth_rxseg_split *rx_seg =
> -			(const struct rte_eth_rxseg_split *)rx_conf->rx_seg;
> -		uint16_t n_seg = rx_conf->rx_nseg;
> -
>   		/* Extended multi-segment configuration check. */
>   		if (rx_conf == NULL || rx_conf->rx_seg == NULL || rx_conf->rx_nseg == 0) {
>   			RTE_ETHDEV_LOG(ERR,
>   				       "Memory pool is null and no extended configuration provided\n");
>   			return -EINVAL;
>   		}
> +
> +		const struct rte_eth_rxseg_split *rx_seg =
> +			(const struct rte_eth_rxseg_split *)rx_conf->rx_seg;
> +		uint16_t n_seg = rx_conf->rx_nseg;
> +

Can you please leave the declaration of the variables at the beginning of the 
block, but move the assignment?