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Date:   Tue, 12 May 2020 18:03:06 -0700 (PDT)
Message-Id: <20200512.180306.1060369920104837686.davem@redhat.com>
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Subject: Re: [PATCH net-next] net: dsa: sja1105: disable rxvlan offload for
 the DSA master
From:   David Miller <davem@redhat.com>
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From: Vladimir Oltean <olteanv@gmail.com>
Date: Wed, 13 May 2020 02:49:21 +0300

> From: Vladimir Oltean <vladimir.oltean@nxp.com>
> 
> On sja1105 operating in best_effort_vlan_filtering mode (when the TPID
> of the DSA tags is 0x8100), it can be seen that __netif_receive_skb_core
> calls __vlan_hwaccel_clear_tag right before passing the skb to the DSA
> packet_type handler.
> 
> This means that the tagger does not see the VLAN tag in the skb, nor in
> the skb meta data.
> 
> The patch that started zeroing the skb VLAN tag is:
> 
>   commit d4b812dea4a236f729526facf97df1a9d18e191c
>   Author: Eric Dumazet <edumazet@xxxxxxxxxx>
>   Date:   Thu Jul 18 07:19:26 2013 -0700
> 
>       vlan: mask vlan prio bits

Eric, please review.