Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933218AbXFEVNT (ORCPT ); Tue, 5 Jun 2007 17:13:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765743AbXFEVNL (ORCPT ); Tue, 5 Jun 2007 17:13:11 -0400 Received: from www.osadl.org ([213.239.205.134]:44637 "EHLO mail.tglx.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1765723AbXFEVNJ (ORCPT ); Tue, 5 Jun 2007 17:13:09 -0400 Subject: Re: [RFC][PATCH] muptiple bugs in PI futexes From: Thomas Gleixner To: Alexey Kuznetsov Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Andrew Morton , Ulrich Drepper In-Reply-To: <20070605210028.GA10084@ms2.inr.ac.ru> References: <20070507144351.GA12302@ms2.inr.ac.ru> <20070523072609.GC6859@elte.hu> <20070523115159.GA30251@ms2.inr.ac.ru> <1181060711.4404.114.camel@chaos> <20070605173949.GA27618@ms2.inr.ac.ru> <1181069306.4404.145.camel@chaos> <1181070953.4404.149.camel@chaos> <20070605210028.GA10084@ms2.inr.ac.ru> Content-Type: text/plain Date: Tue, 05 Jun 2007 23:13:06 +0200 Message-Id: <1181077986.4404.165.camel@chaos> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 (2.10.1-4.fc7) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 855 Lines: 25 On Wed, 2007-06-06 at 01:00 +0400, Alexey Kuznetsov wrote: > Hello! > > > We actually need to do something about this, as we might loop for ever > > there. The robust cleanup code can fail (e.g. due to list corruption) > > and we would see exit_state != 0 and the OWNER_DIED bit would never be > > set, so we are stuck in a busy loop. > > Yes... > > It is possible to take read_lock(&tasklist_lock) before: We really want to avoid the tasklist_lock at all. It's not trivial, but I think it's doable. I send you a patch to test tomorrow morning when my brain recovered from looking at that code :) tglx - 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/