From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753284Ab0CCIfR (ORCPT ); Wed, 3 Mar 2010 03:35:17 -0500 Received: from terminus.zytor.com ([198.137.202.10]:53410 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751325Ab0CCIfO (ORCPT ); Wed, 3 Mar 2010 03:35:14 -0500 Message-ID: <4B8E1F34.7030604@zytor.com> Date: Wed, 03 Mar 2010 00:35:00 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.7) Gecko/20100120 Fedora/3.0.1-1.fc12 Thunderbird/3.0.1 MIME-Version: 1.0 To: "Eric W. Biederman" CC: linux-kernel@vger.kernel.org, Al Viro , Kay Sievers , Greg Kroah-Hartman , Alan Cox Subject: Re: [RFC][PATCH] init: Open /dev/console from rootfs References: In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/02/2010 11:53 PM, Eric W. Biederman wrote: > > To avoid potential problems with an empty /dev open /dev/console > from rootfs instead of waiting to mount our root filesystem and > mounting it there. This effectively guarantees that there will > be a device node, and it won't be on a filesystem that we will > ever unmount, so there are no issues with leaving /dev/console > open and pinning the filesystem. > > This is actually more effective than automatically mounting > devtmpfs on /dev because it removes removes the occasionally > problematic assumption that /dev/console exists from the boot > code. > > With this patch I was able to throw busybox on my /boot partition > (which has no /dev directory) and boot into userspace without > problems. > > The only possible negative consequence I can think of is that > someone out there deliberately used did not use a character device > that is major 5 minor 2 for /dev/console. Does anyone know of a > situation in which that could make sense? > There probably are ... but if so, they can just re-open their new console of choice after creating it, and/or use an initramfs which overrides the default /dev/console. As such, this makes a lot of sense to me. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.