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From:   Xie He <xie.he.0141@gmail.com>
Date:   Thu, 5 Nov 2020 14:47:04 -0800
Message-ID: <CAJht_EPAqy_+Cfh1TXoNeC_j7JDgPWrG-=mMMmQ3ot2gNZuB8A@mail.gmail.com>
Subject: Re: [PATCH net-next] net: x25_asy: Delete the x25_asy driver
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     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 Thu, Nov 5, 2020 at 12:40 PM Arnd Bergmann <arnd@kernel.org> wrote:
>
> > I think this driver never worked. Looking at the original code in
> > Linux 2.1.31, it already has the problems I fixed in commit
> > 8fdcabeac398.
> >
> > I guess when people (or bots) say they "tested", they have not
> > necessarily used this driver to actually try transporting data. They
> > may just have tested open/close, etc. to confirm that the particular
> > problem/issue they saw had been fixed.
>
> It didn't sound like that from the commit message, but it could be.
> For reference:
> https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit?id=aa2b4427c355acaf86d2c7e6faea3472005e3cff

I see. The author of this commit said "I tested by bringing up an x.25
async line using a modified version of slattach." Maybe he only
switched TTY ports from the N_TTY line discipline to the N_X25 line
discipline. To actually test transporting data, we need to either use
AF_PACKET sockets, or use AF_X25 sockets with the X.25 routing table
properly set up. The author of this commit didn't clearly indicate
that he did these.