From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarno Rajahalme <jarno@ovn.org>
Subject: Re: [PATCH v3 net-next 2/3] openvswitch: Use is_skb_forwardable() for length check.
Date: Wed, 30 Nov 2016 13:30:25 -0800
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Pravin Shelar <pshelar@ovn.org>, e@erig.me
To: Jiri Benc <jbenc@redhat.com>
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> On Nov 30, 2016, at 5:51 AM, Jiri Benc <jbenc@redhat.com> wrote:
> 
> On Tue, 29 Nov 2016 15:30:52 -0800, Jarno Rajahalme wrote:
>> @@ -504,11 +485,20 @@ void ovs_vport_send(struct vport *vport, struct sk_buff *skb, u8 mac_proto)
>> 		goto drop;
>> 	}
>> 
>> -	if (unlikely(packet_length(skb, vport->dev) > mtu &&
>> -		     !skb_is_gso(skb))) {
>> -		net_warn_ratelimited("%s: dropped over-mtu packet: %d > %d\n",
>> -				     vport->dev->name,
>> -				     packet_length(skb, vport->dev), mtu);
>> +	if (unlikely(!is_skb_forwardable(vport->dev, skb))) {
> 
> How does this work when the vlan tag is accelerated? Then we can be
> over MTU, yet the check will pass.
> 

I’ll check how other call sites use this.

  Jarno

> Jiri