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Subject: Re: eBPF equivalent of SKF_AD_HATYPE / skb->dev->type
To:     =?UTF-8?Q?Maciej_=c5=bbenczykowski?= <zenczykowski@gmail.com>,
        Alexei Starovoitov <ast@kernel.org>
Cc:     Linux NetDev <netdev@vger.kernel.org>
References: <CANP3RGcxAOY6mBBqFa26Cc4s3++T0QH1z+mcLFbPGdbxZXqTYQ@mail.gmail.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
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Date:   Thu, 24 Jan 2019 12:40:57 +0100
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On 01/24/2019 12:27 PM, Maciej Żenczykowski wrote:
> In classic BPF 'SKF_AD_HATYPE' can be used to fetch skb->dev->type.
> 
> Are my eyes deceiving me, or is there a similar way to get at it from eBPF?
> 
> (while we're at it, skb->dev->mtu would probably be useful too)

Yeah we can add it if you have a concrete use case for access out of the BPF
program, feel free to send a patch. So far nobody ran into the need for it
which is why it hasn't been added yet.

Thanks,
Daniel