[dpdk-stable] [PATCH v1 2/3] net/ring: fix eth_dev device pointer on allocation

[Ferruh Yigit]

On 5/5/2020 8:10 PM, Gaetan Rivet wrote:
> When a net_ring device is allocated, its device pointer is not set
> before calling rte_eth_dev_probing_finish, which is incorrect.
> 
> The following:
>   commit: 96cb19521147 ("net/ring: use EAL APIs in PMD specific API")
>   commit: a6992e961050 ("net/ring: set ethernet device field")
> 
> already attempted to fix this issue in 17.08, which was fine at the
> time. Adding the hook rte_eth_dev_probing_finish() however created this
> bug, as the eth_dev exposed when this hook is executed is expected to be
> complete.
> 
> Remove the prior attempts to fix the issue in rte_pmd_ring_probe() and
> write the pointer properly in do_eth_dev_ring_create().
> 
> Cc: stable at dpdk.org
> Fixes: fbe90cdd776c ("ethdev: add probing finish function")
> Cc: ferruh.yigit at intel.com
> Cc: thomas at monjalon.net
> Signed-off-by: Gaetan Rivet <grive at u256.net>

<...>

> @@ -325,10 +346,17 @@ do_eth_dev_ring_create(const char *name,
>  	data->kdrv = RTE_KDRV_NONE;
>  	data->numa_node = numa_node;
>  
> -	/* finally assign rx and tx ops */
> +	/* assign rx and tx ops */
>  	eth_dev->rx_pkt_burst = eth_ring_rx;
>  	eth_dev->tx_pkt_burst = eth_ring_tx;
>  
> +	/* finally set the rte_device pointer in eth_dev. */
> +	eth_dev->device = ring_device_from_name(name);
> +	if (eth_dev->device == NULL) {
> +		rte_errno = ENODEV;
> +		goto error;
> +	}
> +
>  	rte_eth_dev_probing_finish(eth_dev);
>  	*eth_dev_p = eth_dev;

Why not move the 'rte_eth_dev_probing_finish()' to the 'rte_pmd_ring_probe()',
below where 'eth_dev->device' set?