Re: [PATCH] net/kni: initialize rte_kni_conf to 0 before using it

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

On 3/2/2022 12:33 PM, Harold Huang wrote:
> When kni driver calls eth_kni_start to start device, some fields such as
> min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
> kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
> value. This is unexpected and in some time we could not change the kni
> device mtu with ip link command.
> 

Agree on the problem and the solution, thanks for the fix.

> Fixes: ff1e35fb5f8 ("kni: calculate MTU from mbuf size")
> Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
> ---
>   drivers/net/kni/rte_eth_kni.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
> index c428caf441..23b15edfac 100644
> --- a/drivers/net/kni/rte_eth_kni.c
> +++ b/drivers/net/kni/rte_eth_kni.c
> @@ -128,6 +128,7 @@ eth_kni_start(struct rte_eth_dev *dev)
>   	const char *name = dev->device->name + 4; /* remove net_ */
>   
>   	mb_pool = internals->rx_queues[0].mb_pool;
> +	memset(&conf, 0, sizeof(conf));

Can you prefer initialize to zero, instead of 'memset', I think it
is more clear that way:

  -       struct rte_kni_conf conf;
  +       struct rte_kni_conf conf = { 0 };

>   	strlcpy(conf.name, name, RTE_KNI_NAMESIZE);
>   	conf.force_bind = 0;
>   	conf.group_id = port_id;