Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755328AbXKFVFO (ORCPT ); Tue, 6 Nov 2007 16:05:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754006AbXKFVE7 (ORCPT ); Tue, 6 Nov 2007 16:04:59 -0500 Received: from mx1.redhat.com ([66.187.233.31]:50283 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751063AbXKFVE7 (ORCPT ); Tue, 6 Nov 2007 16:04:59 -0500 Message-ID: <4730D6F3.8030500@redhat.com> Date: Tue, 06 Nov 2007 22:04:51 +0100 From: Milan Broz User-Agent: Thunderbird 2.0.0.5 (X11/20070727) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org, list+2007@smokva.net Subject: Re: dd/mke2fs on loopback hangs References: <20071106131310.GA8628@pintail.smokva.net> In-Reply-To: <20071106131310.GA8628@pintail.smokva.net> X-Enigmail-Version: 0.95.5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1188 Lines: 35 Petar Bogdanovic wrote: > I experience some strange problems with my loopback-on-ext3-setup. > After creating a plain `zeroed' dummy-file and doing a /dev/loop/0 on > it, every dd or mke2fs hangs while doing certain write()s. Here are the > steps just in order to show, how simple the setup is: ... > P.S: $ uname -a > Linux pintail 2.6.23-ARCH #1 SMP PREEMPT Sat Oct 27 09:04:14 UTC > 2007 i686 Intel(R) Pentium(R) M processor 1.70GHz GenuineIntel > GNU/Linux Hi Petar, I saw similar bug report for dm-crypt over loop but reproducible even on stand-alone loop devices - see http://bugzilla.kernel.org/show_bug.cgi?id=8020 The problem was caused by loop io stalling in balance_dirty_pages. Per BDI dirty limit patchset (included in 2.6.24-rc) fixed it. Anyway, you should attach output of process states when system stops responding (output of "echo t >/proc/sysrq-trigger" ) here to allow some analysis. Milan -- mbroz@redhat.com - 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/