Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756907AbXEUGkr (ORCPT ); Mon, 21 May 2007 02:40:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754499AbXEUGkj (ORCPT ); Mon, 21 May 2007 02:40:39 -0400 Received: from hu-out-0506.google.com ([72.14.214.238]:30363 "EHLO hu-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754403AbXEUGki (ORCPT ); Mon, 21 May 2007 02:40:38 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=LSfJcR/Bt7RhQGcgIK9BMULoZ3g5mzGqXrPVll5zM7LhHiaC1GdVZwO5Ws2I/RS06C1NYX0U8kma50mUw7TTUXwMpma3zKeO4uBtGhX71X2ErHnnk39lUOwyK0abODpxF1XeGu0LidsygJQXd9ECQnJ+e+HgsyX/rqajKHTTjbI= Message-ID: <2c0942db0705202340j4dade008v321d605585231d6@mail.gmail.com> Date: Sun, 20 May 2007 23:40:37 -0700 From: "Ray Lee" To: "Ken Chen" Subject: Re: bug in 2.6.22-rc2: loop mount limited to one single iso image Cc: "Andrey Borzenkov" , "Uwe Bugla" , linux-kernel@vger.kernel.org, "Andrew Morton" , "Michal Piotrowski" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <464F42F3.1080300@madrabbit.org> <20070519191751.E51233A23A2@muan.mtu.ru> <200705200124.13026.uwe.bugla@gmx.de> <200705200845.43621.arvidjaar@mail.ru> <2c0942db0705192316s2682807chd23df6f4de29edcb@mail.gmail.com> X-Google-Sender-Auth: d62a181fbdb5c51d Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2138 Lines: 49 On 5/20/07, Ken Chen wrote: > On 5/19/07, Ray Lee wrote: > > Yeah, that's the only one left. I was hoping it wasn't that one, as it > > claimed to have been tested extensively. Guess it wasn't tested with > > udev. > > > > Ken? Ball's in your court. As the patch isn't providing a killer > > feature for 2.6.22, I'd suggest just reverting it for now until the > > issues are ironed out. > > The real solution is to have the user space tool to create these > device nodes in advance. Maybe. But requiring people upgrade their userspace tools or setup for 2.6.22 isn't a reasonable solution. > The original loop patch was coded such that when we open a loop device > N, the immediate adjacent device "N + 1" is created. This will keep > "mount -o loop" happy because it typically does a linear scan to find > a free device. This might be somewhat hackary, but certainly will be > backward compatible before user space solution is deployed. Except userspace is currently expecting 8 loop nodes upon bootup. Creating n+1 when n is opened is good, but racy if userspace tries to mount serveral loop devices in parallel. If the loop device instantiates 8 (or max_loop) upon init, then we're compatible with how things are being done in 2.6.21 and earlier. > However, the code was removed by Al in this commit: > commit 07002e995638b83a6987180f43722a0eb39d4932 > Author: Al Viro > Date: Sat May 12 16:23:15 2007 -0400 > fix the dynamic allocation and probe in loop.c No, backing that code out wasn't good enough -- the reporter tested reverting both of Al's patches out and was still getting errors on boot. It took reverting your original one out as well to make it work. So, a compromise? Let's start with 8 (or max_loop) populated, and then we can move forward separately with teaching userspace new loop tricks. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/