ACK: [PATCH 2/2] xen-netfront: Update features after registering netdev

[Colin Ian King]

On 12/07/18 15:50, Stefan Bader wrote:
> From: Ross Lagerwall <ross.lagerwall at citrix.com>
> 
> Update the features after calling register_netdev() otherwise the
> device features are not set up correctly and it not possible to change
> the MTU of the device. After this change, the features reported by
> ethtool match the device's features before the commit which introduced
> the issue and it is possible to change the device's MTU.
> 
> Fixes: f599c64fdf7d ("xen-netfront: Fix race between device setup and open")
> Reported-by: Liam Shepherd <liam at dancer.es>
> Signed-off-by: Ross Lagerwall <ross.lagerwall at citrix.com>
> Reviewed-by: Juergen Gross <jgross at suse.com>
> Signed-off-by: David S. Miller <davem at davemloft.net>
> 
> BugLink: https://bugs.launchpad.net/bugs/1781413
> 
> (cherry picked from commit 45c8184c1bed1ca8a7f02918552063a00b909bf5)
> Signed-off-by: Stefan Bader <stefan.bader at canonical.com>
> ---
>  drivers/net/xen-netfront.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> index f4479b9..055e92c 100644
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -1968,10 +1968,6 @@ static int xennet_connect(struct net_device *dev)
>  	/* talk_to_netback() sets the correct number of queues */
>  	num_queues = dev->real_num_tx_queues;
>  
> -	rtnl_lock();
> -	netdev_update_features(dev);
> -	rtnl_unlock();
> -
>  	if (dev->reg_state == NETREG_UNINITIALIZED) {
>  		err = register_netdev(dev);
>  		if (err) {
> @@ -1981,6 +1977,10 @@ static int xennet_connect(struct net_device *dev)
>  		}
>  	}
>  
> +	rtnl_lock();
> +	netdev_update_features(dev);
> +	rtnl_unlock();
> +
>  	/*
>  	 * All public and private state should now be sane.  Get
>  	 * ready to start sending and receiving packets and give the driver
> 

Clean cherry pick, looks ok to me.

Acked-by: Colin Ian King <colin.king at canonical.com>