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[209.132.180.67]) by mx.google.com with ESMTP id v77si18649774pfa.219.2019.04.05.01.40.29; Fri, 05 Apr 2019 01:40:45 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730302AbfDEIjy (ORCPT + 99 others); Fri, 5 Apr 2019 04:39:54 -0400 Received: from mout.kundenserver.de ([212.227.126.187]:45045 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730081AbfDEIjx (ORCPT ); Fri, 5 Apr 2019 04:39:53 -0400 Received: from [192.168.1.110] ([95.114.101.225]) by mrelayeu.kundenserver.de (mreue010 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MJmbB-1hVvho3Uj3-00K8oR; Fri, 05 Apr 2019 10:39:45 +0200 Subject: Re: [PATCH] tty: Add NULL TTY driver To: Vincent Whitchurch , Greg KH Cc: jslaby@suse.com, linux-kernel@vger.kernel.org References: <20190403113327.3628-1-vincent.whitchurch@axis.com> <20190403131213.GA4246@kroah.com> <20190403141109.3mdmqbt3mjxrie6k@axis.com> From: "Enrico Weigelt, metux IT consult" Organization: metux IT consult Message-ID: Date: Fri, 5 Apr 2019 10:39:43 +0200 User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20190403141109.3mdmqbt3mjxrie6k@axis.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:tJkoEXbqx7WW9kA3Pxz0gA437JyXrMyV6shrguo+19TwCUFnhup TYOAQ1VQ9GX9XbgwhBMC0l4LDFBVs3xA3PG5nt51N/9IP6qUQSAU4p8gKk+OoEBHvpRf/kw xCya0M628CKER7FbeEtpChF6LbXdLJ9eHXq/sZUBx4cBRtZHzj70o2eUUnMivuXDZXK6hez 2NEFQbekGaB+yKmu2yuBQ== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:iCgrYj7tmN4=:B8EyoMsUbtBE/jZ7n6SOla fYpQoidS4K/d0xlwxyHniz4Je2hzmMX5+Hg0cKiX9EowOdBWyq3j5usKAaefp4t6cQyDXLF5Z EQYYWrG2gYDrXRGddLlU3UDbxfwwQdolt7FZtqGoz8s0IVmmBSYHnHH1ODQMOGKh8NnxVy34r hLygT/PS41R6DrhBfJJ9Z9zfpDDuoOkAoUTsZZfk94+1uImuda4fOZXc9UVBSo/H0l9QC95sJ 02xuDOlJs/n165vXmD+67+F09JeuMVn2oLU1RzGSmQzFBpgu1gkhP6LBkonTa7x43OHtN3IWj ih47yFH8s+QOSO4YhTkWGYaJfJtpDB0TGR9zarVyhZdy35G6ovtawqdx40ft1ht55XjXqZI9F 8/xDA0tNakzX0giRBAMt13iyL7y9dXUbGwaIWq+6OormDMzUIUMWZ6K4sD+h5dHE5ALRbmKNb j8/5r4e3pAqW9hjBQfN/dwV+AObnS9qTEPi0jjzFW1RNaSnkotFFUsc1fPSNar0nm1gvmrKl/ Bmr4MVo74YOBfyYCAxMZQ7v3f1lDFtLp2vqMiUW3ZkiYVeWMLfIVjnUEef0HoMavx9T2qhgQo ivEQcTJEuRVsMUHwed/nvWSXvU3ZSNowmYlIN8wyaQC7HZx1xIl7Lq/FynNSyPBNFzwWcqX8f 2QjZ6c6mlekfop3w6ylppgArSr+U7AsUWHtOFEQ6NQpRn0CckTsDNHIq5+7QTyS2OD6FP0gs5 kBkZmDIj30g7C1EEDxdSM+Jd8Z3jVNRCCwCNV7HcGHD8Bz9zvhhg2Lsymts= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03.04.19 16:11, Vincent Whitchurch wrote: > Especially on embedded systems, it would be convenient to have a simple > way to disable the console (both for kernel and userspace) on a system > which normally uses it, to free up the UART for other things. Just symlinking to /dev/null does not work ? OTOH, if you're introducing a dummy console, wouldn't a ringbuffer that, can be read out later, a better option ? --mtx -- Enrico Weigelt, metux IT consult Free software and Linux embedded engineering info@metux.net -- +49-151-27565287