From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264322AbTLOXEz (ORCPT ); Mon, 15 Dec 2003 18:04:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264323AbTLOXEz (ORCPT ); Mon, 15 Dec 2003 18:04:55 -0500 Received: from mail4.speakeasy.net ([216.254.0.204]:26001 "EHLO mail4.speakeasy.net") by vger.kernel.org with ESMTP id S264322AbTLOXEx (ORCPT ); Mon, 15 Dec 2003 18:04:53 -0500 Date: Mon, 15 Dec 2003 15:04:48 -0800 Message-Id: <200312152304.hBFN4mxq024943@magilla.sf.frob.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Linus Torvalds Cc: Ingo Molnar , Petr Vandrovec , Kernel Mailing List , Andrew Morton Subject: Re: [patch] Re: Problem with exiting threads under NPTL In-Reply-To: Linus Torvalds's message of Sunday, 14 December 2003 14:32:55 -0800 X-Fcc: ~/Mail/linus Emacs: well, why *shouldn't* you pay property taxes on your editor? Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > On Sun, 14 Dec 2003, Ingo Molnar wrote: > > > > are you sure this can happen? eligible_child() does this: > > Interesting. That code should have been enough, but we've later on added > extra code into wait_task_zombie to check _exactly_ the same case because > we saw problems. > > Hmm.. Maybe that was to protect against concurrent wait4()'ers (which can > happen - the wait case only takes the read lock). Threads can wait for > each others children, after all. My recollection about the wait_task_* changes was that they were mostly to address races between concurrent wait4 calls.