Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 25 Feb 2001 19:53:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 25 Feb 2001 19:53:26 -0500 Received: from leibniz.math.psu.edu ([146.186.130.2]:47016 "EHLO math.psu.edu") by vger.kernel.org with ESMTP id ; Sun, 25 Feb 2001 19:53:05 -0500 Date: Sun, 25 Feb 2001 19:53:03 -0500 (EST) From: Alexander Viro To: Jens Axboe cc: Nate Eldredge , linux-kernel@vger.kernel.org Subject: Re: 2.4.2-ac3: loop threads in D state In-Reply-To: <20010226014827.Z7830@suse.de> Message-ID: 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 On Mon, 26 Feb 2001, Jens Axboe wrote: > On Sun, Feb 25 2001, Alexander Viro wrote: > > Let me elaborate: the race is very narrow and takes deliberate efforts to > > hit. It _can_ be triggered, unfortunately. This extra up() will mess your > > life later on. > > What's the worst that can happen? We do an extra up, but loop_thread > will still quit once we hit zero lo_pending. And loop_clr_fd > is still protected by lo_ctl_mutex. Well, for one thing you'll get some surprises next time you losetup the same device ;-) There are more subtle scenarios, but that one is pretty unpleasant in itself. Cheers, Al - 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/