Subject: Re: [Xen-devel] [PATCH] xen-netfront: enable device after manual
 module load
To: Eduardo Otubo <otubo@redhat.com>, linux-kernel@vger.kernel.org
Cc: jgross@suse.com, netdev@vger.kernel.org,
        xen-devel@lists.xenproject.org, mgamal@redhat.com,
        cavery@redhat.com, vkuznets@redhat.com
References: <20180105084216.21719-1-otubo@redhat.com>
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <471397aa-7070-b4fe-991a-f35fa5d3b1f7@oracle.com>
Date: Mon, 8 Jan 2018 10:03:55 -0500
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On 01/05/2018 03:42 AM, Eduardo Otubo wrote:
> When loading the module after unloading it, the network interface would
> not be enabled and thus wouldn't have a backend counterpart and unable
> to be used by the guest.
>
> The guest would face errors like:
>
>   [root@guest ~]# ethtool -i eth0
>   Cannot get driver information: No such device
>
>   [root@guest ~]# ifconfig eth0
>   eth0: error fetching interface information: Device not found
>
> This patch initializes the state of the netfront device whenever it is
> loaded manually, this state would communicate the netback to create its
> device and establish the connection between them.
>
> Signed-off-by: Eduardo Otubo <otubo@redhat.com>

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

Should this go to stable trees as well?

-boris

> ---
>  drivers/net/xen-netfront.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> index c5a34671abda..9bd7ddeeb6a5 100644
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -1326,6 +1326,7 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
>  
>  	netif_carrier_off(netdev);
>  
> +	xenbus_switch_state(dev, XenbusStateInitialising);
>  	return netdev;
>  
>   exit: