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From:   Xie He <xie.he.0141@gmail.com>
Date:   Fri, 6 Nov 2020 03:25:02 -0800
Message-ID: <CAJht_ENiEi1u-fNuE+3NSBY=3BOWL4cC8ndJAH04f-jBR-CW1w@mail.gmail.com>
Subject: Re: [PATCH net-next] net: x25_asy: Delete the x25_asy driver
To:     David Laight <David.Laight@aculab.com>
Cc:     Arnd Bergmann <arnd@kernel.org>, Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Networking <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Arnd Bergmann <arnd@arndb.de>, Martin Schiller <ms@dev.tdt.de>,
        Andrew Hendry <andrew.hendry@gmail.com>,
        Linux X25 <linux-x25@vger.kernel.org>
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On Fri, Nov 6, 2020 at 1:03 AM David Laight <David.Laight@aculab.com> wrote:
>
> Hmmm.... LAPB would expect to have an X.25 level 3 and maybe ISO
> transport (class 0, 2 or 3) sat on top of it.

I actually used AF_PACKET sockets to transport data directly over LAPB
and it worked.

LAPB doesn't need anything from layer 3. It just sees the layer 3
packets as a sequence of packets, numbers them and reliably transports
them in order. It doesn't read the internal contents of the packets.