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Date:   Wed, 20 Nov 2019 09:28:46 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To:     Petr Mladek <pmladek@suse.com>
Cc:     Jonathan Richardson <jonathan.richardson@broadcom.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        gregkh@linuxfoundation.org, jslaby@suse.com,
        sergey.senozhatsky@gmail.com, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Scott Branden <scott.branden@broadcom.com>,
        Ray Jui <ray.jui@broadcom.com>,
        Srinath Mannam <srinath.mannam@broadcom.com>
Subject: Re: console output duplicated when registering additional consoles
Message-ID: <20191120002846.GA255928@google.com>
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On (19/11/19 12:30), Petr Mladek wrote:
> On Mon 2019-11-18 13:38:04, Jonathan Richardson wrote:
> > On Thu, Nov 14, 2019 at 8:33 PM Sergey Senozhatsky
> > <sergey.senozhatsky.work@gmail.com> wrote:
> > >
> > > Gosh, that part of printk is really complex.
> > >
> > > On (19/11/14 10:57), Petr Mladek wrote:
> > > > For a proper solution we would need to match boot and real
> > > > consoles that write messages into the physical device.
> > > > But I am afraid that there is no support for this.
> > >
> > > Wouldn't those have same tty driver?
> 
> Interesting idea. Well, do early consoles have tty driver?

Good question! I'm not sure.
netcon, for instance, doesn't have tty driver, yet still has to find
a proper net device to write the data to. They have some magic inside.

	-ss