From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751882AbXCLXM3 (ORCPT ); Mon, 12 Mar 2007 19:12:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752130AbXCLXM2 (ORCPT ); Mon, 12 Mar 2007 19:12:28 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:49784 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751882AbXCLXM2 (ORCPT ); Mon, 12 Mar 2007 19:12:28 -0400 Date: Tue, 13 Mar 2007 00:12:20 +0100 From: Pavel Machek To: Dave Jones , Andrew Morton , alon.barlev@gmail.com, ak@suse.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86_64, i386: Add command line length to boot protocol Message-ID: <20070312231220.GC9749@elf.ucw.cz> References: <20070306181430.GB3151@strauss.suse.de> <20070306182134.GB9491@redhat.com> <20070312104352.GA4313@ucw.cz> <20070312205513.GC21835@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070312205513.GC21835@redhat.com> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > > +cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line, > > > > > > Why a long? It's unlikely that someone is going to have a command line > > > bigger than 0xffff. > > > > Well, I could imagine overflowing that. Describing your numa setup, > > excluding few bad bits of ram using memmap=exact, set up your boot > > over iscsi on cmdline.... these are likely to eat insane ammount of > > cmdline space. > > 65535 characters? Are you for real? > Stop and think about just how big that is. If you have to create > a boot command line that long, you have serious, serious issues. Well, it is about the same size as my .config... I agree we are unlikely to hit it any time soon... I could imagine some (ab)uses, like fixed_acpi_bios=, but those are ugly. I could also imagine some uses where entire embedded machine is described at kernel commandline. Yes, all those are ugly/unlikely. OTOH saving 2 bytes does not seem like that great goal. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html