From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750967AbXDAQxN (ORCPT ); Sun, 1 Apr 2007 12:53:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751345AbXDAQxN (ORCPT ); Sun, 1 Apr 2007 12:53:13 -0400 Received: from hosting4p.com ([81.0.235.160]:51825 "EHLO micron1.hosting4p.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750967AbXDAQxM (ORCPT ); Sun, 1 Apr 2007 12:53:12 -0400 Message-ID: <460FE380.2050608@slax.org> Date: Sun, 01 Apr 2007 18:53:20 +0200 From: Tomas M User-Agent: Thunderbird 1.5.0.10 (Windows/20070221) MIME-Version: 1.0 To: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [patch] remove artificial software max_loop limit References: <20070330141524.5f6cff29.akpm@linux-foundation.org> In-Reply-To: <20070330141524.5f6cff29.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: > On Fri, 30 Mar 2007 02:25:37 -0700 > "Ken Chen" wrote: > >> -module_param(max_loop, int, 0); >> -MODULE_PARM_DESC(max_loop, "Maximum number of loop devices (1-256)"); > > So.. this change will cause a fatal error for anyone who is presently > using max_loop, won't it? If they're doing that within their > initramfs/initrd/etc then things could get rather ugly for them. I consider myself the most precious user of max_loop. The max_loop parameter would cause a fatal error only in the case if you modprobe loop manually, for example: $ modprobe loop max_loop=200 But people don't usually use this, read below. > I don't know how much of a problem this will be in practice - do > people use max_loop much? yes, but no as a module parameter. People usually use max_loop as a 'kernel boot parameter' passed in APPEND section in a boot loader (such as LILO for example), not as a parameter for module in initrd. Why? Because it's easier; people are lazy, people compile loop.c into kernel so they don't need to update the loop.ko module in initrd every time a new Kernel is released. I believe that IF you _really_ need to preserve the boot parameter, then the parameter should _not_ be ignored, rather it should have the same function like before - to limit the loop driver so if you use max_loop=10 for example, it should not allow loop.c to create more than 10 loops. And if no parameter is used at all, there will be unlimited amount of loops. Simply clever :) This will make it _completely_ backward-compatible, with very small code change I guess. Just my two cents. Thank you for reading so far. Tomas M slax.org