Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756591AbXKKAig (ORCPT ); Sat, 10 Nov 2007 19:38:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755822AbXKKAi2 (ORCPT ); Sat, 10 Nov 2007 19:38:28 -0500 Received: from artax.karlin.mff.cuni.cz ([195.113.31.125]:47943 "EHLO artax.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755810AbXKKAi2 (ORCPT ); Sat, 10 Nov 2007 19:38:28 -0500 Date: Sun, 11 Nov 2007 01:38:27 +0100 (CET) From: Mikulas Patocka To: Peter Zijlstra cc: Andrew Morton , linux-kernel@vger.kernel.org, WU Fengguang , Miklos Szeredi Subject: Re: Temporary lockup on loopback block device In-Reply-To: <1194735752.5828.1.camel@lappy> Message-ID: References: <20071110145444.a6993df1.akpm@linux-foundation.org> <1194735752.5828.1.camel@lappy> X-Personality-Disorder: Schizoid MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 890 Lines: 20 > > Arguably we just have the wrong backing-device here, and what we should do > > is to propagate the real backing device's pointer through up into the > > filesystem. There's machinery for this which things like DM stacks use. > > > > I wonder if the post-2.6.23 changes happened to make this problem go away. > > The per BDI dirty stuff in 24 should make this work, I just checked and > loopback thingies seem to have their own BDI, so all should be well. This is not only about loopback (I think the lockup can happen even without loopback) --- the main problem is: Why are there over-limit dirty pages that no one is writing? Mikulas - 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/