Re: [PATCH net-next V6 4/4] virtio-net: synchronize probe with ndo_set_features

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Aug 06, 2024 at 10:22:24AM +0800, Jason Wang wrote:
> We calculate guest offloads during probe without the protection of
> rtnl_lock. This lead to race between probe and ndo_set_features. Fix
> this by moving the calculation under the rtnl_lock.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Fixes tag pls?

> ---
>  drivers/net/virtio_net.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index fc5196ca8d51..1d86aa07c871 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -6596,6 +6596,11 @@ static int virtnet_probe(struct virtio_device *vdev)
>  		netif_carrier_on(dev);
>  	}
>  
> +	for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
> +		if (virtio_has_feature(vi->vdev, guest_offloads[i]))
> +			set_bit(guest_offloads[i], &vi->guest_offloads);
> +	vi->guest_offloads_capable = vi->guest_offloads;
> +
>  	rtnl_unlock();
>  
>  	err = virtnet_cpu_notif_add(vi);
> @@ -6604,11 +6609,6 @@ static int virtnet_probe(struct virtio_device *vdev)
>  		goto free_unregister_netdev;
>  	}
>  
> -	for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
> -		if (virtio_has_feature(vi->vdev, guest_offloads[i]))
> -			set_bit(guest_offloads[i], &vi->guest_offloads);
> -	vi->guest_offloads_capable = vi->guest_offloads;
> -
>  	pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
>  		 dev->name, max_queue_pairs);
>  
> -- 
> 2.31.1