From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_EF,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 7CC191F461 for ; Mon, 8 Jul 2019 13:11:20 +0000 (UTC) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:in-reply-to :message-id:mime-version:content-type; q=dns; s=default; b=go1UN eekyJxsEVncgc28LbMDCs68lIQ7M8RL3LCW4xk5htakTtKTleiJfXcM0muBSL2eA 71oEnBNNG2XJL+DJoujXdcgSL256hHyVpwjYAztX4BGlKDHESirvnRa0DAtY4tz+ geAp82XYgiNZunNihZBBM1VFQyglBgvBAlnY0c= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:in-reply-to :message-id:mime-version:content-type; s=default; bh=vrn9Jsu89aH x7V9jQ7J3MPr0E6Q=; b=x8xMA6/jZFOpiU23mTbVbiEGf+8GHIbjQqhGl08dlC1 aMzSafoD7vCQ1N/4/QnDmW0hMRMnZngcmo2ENgSlV1UCCd4CWoFPbZ3BVXo2m5ss 1L7Z8BvZ1SKLplLntM+nlYSKID0O7aJh20pOEoeCllHDR/dLwjdbDl3X2bcSBcWg = Received: (qmail 86146 invoked by alias); 8 Jul 2019 13:11:18 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 86136 invoked by uid 89); 8 Jul 2019 13:11:17 -0000 Authentication-Results: sourceware.org; auth=none X-HELO: mx1.redhat.com From: Florian Weimer To: Adhemerval Zanella Cc: Carlos O'Donell , libc-alpha@sourceware.org Subject: Re: [PATCH] nptl: Fix deadlock on atfork handler which calls dlclose (BZ#24595) References: <20190523133048.14922-1-adhemerval.zanella@linaro.org> <77021a69-c1a9-b41a-4396-5201915e3fa3@linaro.org> <87blztulg7.fsf@oldenburg2.str.redhat.com> <87lfyxt0fk.fsf@mid.deneb.enyo.de> <9b7c942b-ffba-4032-0d85-42a3b401d12f@linaro.org> <87o93sru1b.fsf@oldenburg2.str.redhat.com> <0636dd42-5cdb-7bdd-5ad7-0614bad0da78@linaro.org> <87pno7q5fy.fsf@oldenburg2.str.redhat.com> <20126ef9-c2fa-1c2c-d62f-5c509df928fc@linaro.org> Date: Mon, 08 Jul 2019 15:11:10 +0200 In-Reply-To: <20126ef9-c2fa-1c2c-d62f-5c509df928fc@linaro.org> (Adhemerval Zanella's message of "Fri, 24 May 2019 11:49:25 -0300") Message-ID: <87tvbwr7rl.fsf@oldenburg2.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain I have thought about this some more and now wonder if we should add a generic copy-on-write list which supports deletions in the middle. We could use it for an internal copy of _IO_list_all (which is unfortunately part of the ABI), too. It would help with code that has to deal with callbacks where the callbacks can acquire the list lock or modify the list. Thanks, Florian