Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757469AbZJDQhq (ORCPT ); Sun, 4 Oct 2009 12:37:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757386AbZJDQhp (ORCPT ); Sun, 4 Oct 2009 12:37:45 -0400 Received: from mail-pz0-f179.google.com ([209.85.222.179]:36845 "EHLO mail-pz0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755163AbZJDQhp (ORCPT ); Sun, 4 Oct 2009 12:37:45 -0400 Message-ID: <4AC8CF32.8060108@anirban.org> Date: Sun, 04 Oct 2009 09:37:06 -0700 From: Anirban Sinha User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.1.4pre) Gecko/20090915 Thunderbird/3.0b4 MIME-Version: 1.0 To: Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, Darren Hart , Peter Zijlstra , Kaz Kylheku , Anirban Sinha Subject: Re: futex question References: <20091001092218.GH15345@elte.hu> <4AC68F13.8050601@us.ibm.com> In-Reply-To: X-Enigmail-Version: 0.97a Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1050 Lines: 20 >> 1) What caused you to instrument this path in the first place? Were you >> seeing some unexpected behavior? >> >> 2) I wonder why we would need to clear the robust list, but I don't see other >> things like pi_blocked_on, etc. in execve being cleared. I'm looking into >> this now (perhaps we don't do the same cleanup, need to check).... have to get >> on the plane... > > Hmm, just setting the robust list pointer to NULL fixes the problem at > hand, but I wonder whether we need to call exit_robust_list() as > well. hmm. That is an interesting thought. But I wonder if acquiring a lock and then exec()ing in the critical section is a legal thing to do. It does not feel right. Currently, with or without my change, such a thing would indefinitely block other waiters on the same futex. Ani -- 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/