Re: [PATCH V2 3/6] ethdev: fix push new event

[Thomas Monjalon <thomas@monjalon.net>]

15/09/2022 14:45, Huisong Li:
> The 'state' in struct rte_eth_dev may be used to update some information
> when app receive these events. For example, when app receives a new event,
> app may get the socket id of this port by calling rte_eth_dev_socket_id to
> setup the attached port. The 'state' is used in rte_eth_dev_socket_id.
> 
> If the state isn't modified to RTE_ETH_DEV_ATTACHED before pushing the new
> event, app will get the socket id failed. So this patch moves pushing event
> operation after the state updated.
> 
> Fixes: 99a2dd955fba ("lib: remove librte_ prefix from directory names")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Huisong Li <lihuisong@huawei.com>
> ---
>  lib/ethdev/ethdev_driver.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib/ethdev/ethdev_driver.c b/lib/ethdev/ethdev_driver.c
> index a285f213f0..a6616f072b 100644
> --- a/lib/ethdev/ethdev_driver.c
> +++ b/lib/ethdev/ethdev_driver.c
> @@ -206,9 +206,9 @@ rte_eth_dev_probing_finish(struct rte_eth_dev *dev)
>  	if (rte_eal_process_type() == RTE_PROC_SECONDARY)
>  		eth_dev_fp_ops_setup(rte_eth_fp_ops + dev->data->port_id, dev);
>  
> -	rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_NEW, NULL);
>  
>  	dev->state = RTE_ETH_DEV_ATTACHED;
> +	rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_NEW, NULL);
>  }

As explained in the first patch, I don't think it is a good solution.
We should not allow the port to be used until the end of probing.
When RTE_ETH_EVENT_NEW is sent, the device is allocated but
not ready for use. If an entity like failsafe decides to take ownership
of the port, then the application should not consider it at all.
For these reasons, we should limit which operations can be done
during RTE_ETH_EVENT_NEW processing.
That's why I've proposed creating a new state RTE_ETH_DEV_ALLOCATED,
not sure why you didn't follow this advice.