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Date: Thu, 2 Nov 2017 17:53:22 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: Paul Menzel <pmenzel+linux-serial@molgen.mpg.de>
Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: How to enable output to serial console at run-time?
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On Thu, Nov 02, 2017 at 04:39:36PM +0100, Paul Menzel wrote:
> Dear Linux folks,
> 
> 
> If I want to output the Linux kernel messages to the serial console, but the
> `console=ttyS…` line is missing on the Linux command line, is there a way to
> activate that during run-time by, for example, using the sysfs interface?

Why not change the command line to enable it properly?

thanks,

greg k-h