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Date:   Thu, 10 Mar 2022 19:54:29 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     menglong8.dong@gmail.com
Cc:     dsahern@kernel.org, nhorman@tuxdriver.com, ast@kernel.org,
        daniel@iogearbox.net, andrii@kernel.org, kafai@fb.com,
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        alobakin@pm.me, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, bpf@vger.kernel.org,
        Mengen Sun <mengensun@tencent.com>,
        Hao Peng <flyingpeng@tencent.com>
Subject: Re: [PATCH] net: skb: move enum skb_drop_reason to uapi
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On Fri, 11 Mar 2022 11:28:28 +0800 menglong8.dong@gmail.com wrote:
> From: Menglong Dong <imagedong@tencent.com>
> 
> Move the definition of 'enum skb_drop_reason' in 'skbuff.h' to the uapi
> header 'net_dropmon.h', therefore some users, such as eBPF program, can
> make use of it.

BPF does not need an enum definition to be part of the uAPI to make use
of it. BTF should encode the values, and CO-RE can protect from them
changing, AFAIU. I think we need a better example user / justification.