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Date:   Mon, 23 Nov 2020 11:36:22 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Xie He <xie.he.0141@gmail.com>
Cc:     Martin Schiller <ms@dev.tdt.de>,
        Andrew Hendry <andrew.hendry@gmail.com>,
        "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>
Subject: Re: [PATCH net-next v4 2/5] net/lapb: support netdev events
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On Mon, 23 Nov 2020 03:17:54 -0800 Xie He wrote:
> 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.

More of a historic thing than a requirement AFAIK. Some software
devices, e.g. loopback will not generate carrier events. But in this
case looks like all the devices Martin wants to handle are lapb.

> >  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 :)

Xie other than this the patches look good to you?

Martin should I expect a respin to follow Xie's suggestion 
or should I apply v4?