Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754961AbYFPMD5 (ORCPT ); Mon, 16 Jun 2008 08:03:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752836AbYFPMDv (ORCPT ); Mon, 16 Jun 2008 08:03:51 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:54275 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752692AbYFPMDu (ORCPT ); Mon, 16 Jun 2008 08:03:50 -0400 Date: Mon, 16 Jun 2008 12:46:02 +0100 From: Alan Cox To: Alan Cox Cc: Johannes Weiner , "Rafael J. Wysocki" , Linux Kernel Mailing List Subject: Re: [Bug 10741] bug in `tty: BKL pushdown'? Message-ID: <20080616124602.54910afd@lxorguk.ukuu.org.uk> In-Reply-To: <20080616113313.2f932f8d@lxorguk.ukuu.org.uk> References: <873andbst2.fsf@saeurebad.de> <20080616113313.2f932f8d@lxorguk.ukuu.org.uk> X-Mailer: Claws Mail 3.4.0 (GTK+ 2.12.8; x86_64-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 964 Lines: 28 On Mon, 16 Jun 2008 11:33:13 +0100 Alan Cox wrote: > > The bug still exists, however, a bisect on another machine with the same > > userland leads to different commit > > (47f86834bbd4193139d61d659bebf9ab9d691e37 "redo locking of tty->pgrp"), > > so it is not all that clear and stable. > > Now that would actually make a lot more sense as a root cause. Experiment time. In _proc_set_tty() in tty_io.c move the tty->session = get_pid(task_session(tsk)); back inside the lock just before tty->pgrp = get_pid(task_pgrp(tsk)); Alan -- "Standards committees don't like hashing. It looks complicated and insufficiently deterministic on an overhead projector." - Vern Schryver -- 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/