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From:   Jesper Dangaard Brouer <jbrouer@redhat.com>
Message-ID: <e4a9fa43-06f7-5271-effc-20cac59b0e64@redhat.com>
Date:   Mon, 15 May 2023 17:07:19 +0200
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Cc:     brouer@redhat.com, bpf@vger.kernel.org,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
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        KP Singh <kpsingh@kernel.org>, Jiri Olsa <jolsa@kernel.org>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        Anatoly Burakov <anatoly.burakov@intel.com>,
        Alexander Lobakin <alexandr.lobakin@intel.com>,
        Magnus Karlsson <magnus.karlsson@gmail.com>,
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        netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND bpf-next 10/15] ice: Implement VLAN tag hint
To:     Larysa Zaremba <larysa.zaremba@intel.com>,
        Stanislav Fomichev <sdf@google.com>
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 <20230512152607.992209-11-larysa.zaremba@intel.com>
 <ZF6F+UQlXA9REqag@google.com> <ZGI2oDcWX+o9Ea0T@lincoln>
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On 15/05/2023 15.41, Larysa Zaremba wrote:
>>> +	*vlan_tag = ice_get_vlan_tag_from_rx_desc(xdp_ext->eop_desc);
>> Should we also do the following:
>>
>> if (!*vlan_tag)
>> 	return -ENODATA;
>>
>> ?
> Oh, returning VLAN tag with zero value really made sense to me at the beginning,
> but after playing with different kinds of packets, I think returning error makes
> more sense. Will change.
> 

IIRC then VLAN tag zero is also a valid id, right?

--Jesper