From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753267AbYICQXR (ORCPT ); Wed, 3 Sep 2008 12:23:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752057AbYICQXF (ORCPT ); Wed, 3 Sep 2008 12:23:05 -0400 Received: from hera.kernel.org ([140.211.167.34]:50103 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752056AbYICQXE (ORCPT ); Wed, 3 Sep 2008 12:23:04 -0400 Message-ID: <48BEB98C.8030303@kernel.org> Date: Wed, 03 Sep 2008 18:21:32 +0200 From: Tejun Heo User-Agent: Thunderbird 2.0.0.12 (X11/20071114) MIME-Version: 1.0 To: "H. Peter Anvin" CC: device@lanana.org, Linux Kernel Mailing List , Jens Axboe Subject: Re: regarding major number of block extended devt References: <48BD30F9.6080108@kernel.org> <48BD3313.7090906@kernel.org> <48BD9F36.8000704@zytor.com> <48BE0EDB.20107@kernel.org> <48BEB759.4050503@zytor.com> In-Reply-To: <48BEB759.4050503@zytor.com> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Wed, 03 Sep 2008 16:22:52 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org H. Peter Anvin wrote: > But just allocating a big bucket of device numbers and throw it all into > a pot semirandomly is likely to cause more damage, not less. To use ext devt, the system has to use udev for device numbers. As long as udev is used, the major number doesn't matter. In addition, breaking drastically (e.g. can't find the device) seems better than subtle failure (e.g. weird partition number calculation based on the traditional minor number scheme) and CONFIG_DEBUG_BLOCK_EXT_DEVT is exactly aimed at making breakages obvious. I don't really see there's much to gain by sharing the original major numbers. Thanks. -- tejun