Subject: Re: [net-next rfc v7 2/3] virtio_net: multiqueue support

From: Jason Wang <[email-masked]>
Date: Mon, 03 Dec 2012 18:30:49 +0800

On 12/03/2012 06:14 PM, Michael S. Tsirkin wrote:
> On Tue, Nov 27, 2012 at 06:15:59PM +0800, Jason Wang wrote:
>> > -	if (!try_fill_recv(&vi->rq, GFP_KERNEL))
>> > -		schedule_delayed_work(&vi->rq.refill, 0);
>> > +	for (i = 0; i < vi->max_queue_pairs; i++)
>> > +		if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
>> > +			schedule_delayed_work(&vi->rq[i].refill, 0);
>> >  
>> >  	mutex_lock(&vi->config_lock);
>> >  	vi->config_enable = true;
>> >  	mutex_unlock(&vi->config_lock);
>> >  
>> > +	BUG_ON(virtnet_set_queues(vi));
>> > +
>> >  	return 0;
>> >  }
>> >  #endif
> Also crashing on device nack of command is also not nice.
> In this case it seems we can just switch to
> single-queue mode which should always be safe.

Not sure it's safe. It depends on the reason why this call fails. If we
left a state that the driver only use single queue but the device use
multi queues, we may still lost the network.