From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262347AbTIEJRr (ORCPT ); Fri, 5 Sep 2003 05:17:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262358AbTIEJRr (ORCPT ); Fri, 5 Sep 2003 05:17:47 -0400 Received: from chello080108023209.34.11.vie.surfer.at ([80.108.23.209]:37504 "HELO leto2.endorphin.org") by vger.kernel.org with SMTP id S262347AbTIEJRp (ORCPT ); Fri, 5 Sep 2003 05:17:45 -0400 Date: Fri, 5 Sep 2003 11:17:44 +0200 To: linux-kernel@vger.kernel.org Cc: Andries.Brouwer@cwi.nl Subject: test4: loop deadlock Message-ID: <20030905091744.GA2320@leto2.endorphin.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="0F1p//8PRICkK4MW" Content-Disposition: inline User-Agent: Mutt/1.3.28i From: Fruhwirth Clemens X-Delivery-Agent: TMDA/0.51 (Python 2.1.3 on Linux/i686) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --0F1p//8PRICkK4MW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Block-backed loop devices can cause a deadlock. How to reproduce: You need ~100mb partition. Boot with mem=3D32m (otherwise the cache will be to big in the most cases)= =20 swapoff -a losetup /dev/loop0 /dev/hdXX for i in `seq 1 10`; do dd if=3D/dev/zero of=3D/dev/loop0 & done Now the box "should" freeze. This doesn't happen with filebased read/write or blockbased read. Jari's loop survives this stress test without problems. So probably we should continue with merging his loop changes. Andries, are you still interested in that? (As long term solution for the indisputable ugliness of loop.c: just throw away block-backend support and move the cryptostuff to device mapper: http://marc.theaimsgroup.com/?l=3Dlinux-kernel&m=3D105967481007242&w=3D2=20 The patch is working great, btw, much more stable than loop+cryptoloop. I'd really like to see it merged) Regards, Clemens --0F1p//8PRICkK4MW Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE/WFS4W7sr9DEJLk4RAvdEAJ4xC1/9pUepE+YTUnUDrhGhYf5SIQCgjFvl 5mXCcyxSTHGh+1bqCOXreOw= =rE5h -----END PGP SIGNATURE----- --0F1p//8PRICkK4MW--