Re: [PATCH net] be2net: Fix NULL pointer dereference in be_tx_timeout()

[David Miller <davem@davemloft.net>]

From: Ivan Vecera <ivecera@redhat.com>
Date: Wed, 28 Nov 2018 11:12:22 +0100

> On 27. 11. 18 23:51, David Miller wrote:
>> From: Petr Oros <poros@redhat.com>
>> Date: Thu, 22 Nov 2018 15:24:07 +0100
>> 
>>> @@ -4700,8 +4700,11 @@ int be_update_queues(struct be_adapter
>>> *adapter)
>>>   	struct net_device *netdev = adapter->netdev;
>>>   	int status;
>>>   -	if (netif_running(netdev))
>>> +	if (netif_running(netdev)) {
>>> +		/* prevent netdev watchdog during tx queue destroy */
>>> +		netif_carrier_off(netdev);
>>>   		be_close(netdev);
>>> +	}
>> This will make userspace networking daemons will think that the link
>> went down.
>> This absolutely should not be a side effect of making a simple
>> TX queue configuration change via ethtool.
>> 
> 
> Yes, you're right Dave. But the same thing (netif_carrier_off()) is
> done by number of other drivers (igb, tg3, ixgbe...) during
> .set_channels() callback. The patch that Petr sent does the
> practically the same thing like this one:

Bug exist in other drivers, thanks for reporting that.

It doesn't mean you should add the same bug here as well.