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Date:   Sun, 21 Feb 2021 08:39:31 +0200
From:   Leon Romanovsky <leon@kernel.org>
To:     Xie He <xie.he.0141@gmail.com>
Cc:     Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Linux X25 <linux-x25@vger.kernel.org>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Martin Schiller <ms@dev.tdt.de>,
        Krzysztof Halasa <khc@pm.waw.pl>,
        Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org
Subject: Re: [PATCH net-next RFC v4] net: hdlc_x25: Queue outgoing LAPB frames
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On Fri, Feb 19, 2021 at 12:28:12PM -0800, Xie He wrote:
> On Fri, Feb 19, 2021 at 10:39 AM Jakub Kicinski <kuba@kernel.org> wrote:
> >
> > Not entirely sure what the argument is about but adding constants would
> > certainly help.
>
> Leon wants me to replace this:
>
> dev->needed_headroom = 3 - 1;
>
> with this:
>

Leon wants this line to be written good enough:

> /* 2 is the result of 3 - 1 */

And this line like you wrote here:

> dev->needed_headroom = 2;


<...>

> Yes, this patch will break backward compatibility. Users with old
> scripts will find them no longer working.

Did you search in debian/fedora code repositories to see if such scripts exist
as part of any distro package?

Thanks