Re: [PATCH net-next 2/2] xen-netback: handle frontends that fail to transition through Closing

[Wei Liu <wei.liu2@citrix.com>]

On Fri, Sep 20, 2013 at 01:56:31PM +0100, Paul Durrant wrote:
> Some old Windows frontends fail to transition through the xenbus Closing
> state and move directly from Connected to Closed. Handle this case properly.
> 
> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> Cc: David Vrabel <david.vrabel@citrix.com>
> Cc: Wei Liu <wei.liu2@citrix.com>
> Cc: Ian Campbell <ian.campbell@citrix.com>
> ---
>  drivers/net/xen-netback/xenbus.c |    2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
> index a53782e..bcaa25b 100644
> --- a/drivers/net/xen-netback/xenbus.c
> +++ b/drivers/net/xen-netback/xenbus.c
> @@ -265,6 +265,8 @@ static void frontend_changed(struct xenbus_device *dev,
>  		break;
>  
>  	case XenbusStateClosed:
> +		if (dev->state == XenbusStateConnected)
> +			disconnect_backend(dev);

Could you please add a comment above this change stating that this is a
workaround for some old frontend that we cannot fix / upgrade.

We would still like to later frontend goes through the normal connected
-> closing -> closed path.

Wei.

>  		xenbus_switch_state(dev, XenbusStateClosed);
>  		if (xenbus_dev_is_online(dev))
>  			break;
> -- 
> 1.7.10.4