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From:   Xie He <xie.he.0141@gmail.com>
Date:   Mon, 23 Nov 2020 03:17:54 -0800
Message-ID: <CAJht_EPtPDOSYfwc=9trBMdzLw4BbTzJbGvaEgWoyiy2624Q+Q@mail.gmail.com>
Subject: Re: [PATCH net-next v4 2/5] net/lapb: support netdev events
To:     Martin Schiller <ms@dev.tdt.de>
Cc:     Andrew Hendry <andrew.hendry@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Linux X25 <linux-x25@vger.kernel.org>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Mon, Nov 23, 2020 at 2:38 AM Martin Schiller <ms@dev.tdt.de> wrote:
>
> Well, one could argue that we would have to repair these drivers, but I
> don't think that will get us anywhere.

Yeah... One problem I see with the Linux project is the lack of
docs/specs. Often we don't know what is right and what is wrong.

>  From this point of view it will be the best to handle the NETDEV_UP in
> the lapb event handler and establish the link analog to the
> NETDEV_CHANGE event if the carrier is UP.

Thanks! This way we can make sure LAPB would automatically connect in
all situations.

Since we'll have a netif_carrier_ok check in NETDEV_UP handing, it
might make the code look prettier to also have a netif_carrier_ok
check in NETDEV_GOING_DOWN handing (for symmetry). Just a suggestion.
You can do whatever looks good to you :)

Thanks!