Re: [dpdk-dev] [PATCH] ethdev: fix one MAC address occupies two index in mac addrs

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 9/22/21 6:36 AM, Min Hu (Connor) wrote:
> From: Huisong Li <lihuisong@huawei.com>
> 
> Use the testpmd to perform the following operations:
> 1) mac_addr add 0 00:18:2D:00:00:90
> 2) mac_addr add 0 00:18:2D:00:00:91
> 3) mac_addr add 0 00:18:2D:00:00:92
> 4) mac_addr set 0 00:18:2D:00:00:91
> 5) show port 0 macs
> Number of MAC address added: 4
>   00:18:2D:00:00:91
>   00:18:2D:00:00:90
>   00:18:2D:00:00:91
>   00:18:2D:00:00:92
> 
> This is due to the reason that if the address has been added as a
> non-default MAC address by rte_eth_dev_mac_addr_add API, it doesn't remove
> from dev->data->mac_addrs[] when set default MAC address with the same
> address.
> 
> Fixes: 854d8ad4ef68 ("ethdev: add default mac address modifier")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Huisong Li <lihuisong@huawei.com>
> Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
> ---
>  lib/ethdev/rte_ethdev.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
> index daf5ca9242..77657a3314 100644
> --- a/lib/ethdev/rte_ethdev.c
> +++ b/lib/ethdev/rte_ethdev.c
> @@ -4360,6 +4360,7 @@ int
>  rte_eth_dev_default_mac_addr_set(uint16_t port_id, struct rte_ether_addr *addr)
>  {
>  	struct rte_eth_dev *dev;
> +	int index;
>  	int ret;
>  
>  	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
> @@ -4381,6 +4382,20 @@ rte_eth_dev_default_mac_addr_set(uint16_t port_id, struct rte_ether_addr *addr)
>  	if (ret < 0)
>  		return ret;
>  
> +	/*
> +	 * If the address has been added as a non-default MAC address by
> +	 * rte_eth_dev_mac_addr_add API, it should be removed from
> +	 * dev->data->mac_addrs[].
> +	 */
> +	index = eth_dev_get_mac_addr_index(port_id, addr);
> +	if (index > 0) {
> +		/* remove address in NIC data structure */
> +		rte_ether_addr_copy(&null_mac_addr,
> +				    &dev->data->mac_addrs[index]);
> +		/* reset pool bitmap */
> +		dev->data->mac_pool_sel[index] = 0;
> +	}
> +
>  	/* Update default address in NIC data structure */
>  	rte_ether_addr_copy(addr, &dev->data->mac_addrs[0]);
>  
> 

If I change default MAC to something else later, should the old
default MAC be returned to some specific pools? I guess it is
hard to do. If the change is accepted, the behaviour must be
documented in rte_eth_dev_default_mac_addr_set() description.