Received: by 2002:ad5:474a:0:0:0:0:0 with SMTP id i10csp3896939imu; Mon, 14 Jan 2019 10:59:49 -0800 (PST) X-Google-Smtp-Source: ALg8bN4FBxPsS3speB2XqRDv/iKHcmuzNKPkVAzpoozuSAQ6FCifM8bbQQcmmPd4IRH5h4LG0XL9 X-Received: by 2002:a62:3006:: with SMTP id w6mr27027941pfw.258.1547492389753; Mon, 14 Jan 2019 10:59:49 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1547492389; cv=none; d=google.com; s=arc-20160816; b=sutitgSk0zAJ1RGtueGbEuHl5AhZyKCjKSc/lsHpy/3pPMTXGE87lToDaPtV3V1kpy miy3XNHiZ2fY5E7XXQEXIFQM3rS7bJ5kU6FmrzaTNnCPZSMiLKnziljSFKjmPyGoElvu AWY/Lr5T34oWWSjJLdkWCiWahbF3xsLI+OBmjxdXidAPltDgBU4jOAZyxKe3mYMvqh0o Ytz90MnZiG/hPCZjTWE0nMMVArXO0xTuLMb6MGKtDhC4xfG422Z2NCxjv39zSYiL14Zh BxEtxBiOtSVEXexJI9JSiMzcWcFvVhNHSwXkUxz+3XtxozmCgpGipV38l1T09J11R3lo VpvQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:user-agent:message-id :in-reply-to:date:references:subject:cc:to:from; bh=CFEvEsgAdRUEvFFEMfXLHA/XKz70xLKjgCMtWiKBPVg=; b=QutltDGcLybXOrqBi9y5A2IphEI6Iud75kKGIzscdswP1aa/fIHiUCKGDd84IqhUEv owPk4RSKcQp4JAm6Ywm8gf5kxFPH/Est37S62KSqMDBMBJQ0y/k3DuKGHafELUeycccY FFTSiHOAz+5a0mP5gZmnZhDiZjYp0a4WsDSAQ//Hxid81OcW8DlBNQ04k/4Sw8F1/nsy kTKSri6VG3lvGPVsjp4x3E2Lso62EUFcPOmoN0mf9xqCihmfBWRgLLQGivZOvgIa/mBK QHhIrcokOeqWUsEk+9nFBZs1rG8m98gjeNW2gcrgDFKH815gJP/N8P9TbNjIGjqj5ZDC hUVQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o10si943490pgg.373.2019.01.14.10.59.33; Mon, 14 Jan 2019 10:59:49 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726812AbfANS5M (ORCPT + 99 others); Mon, 14 Jan 2019 13:57:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43780 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726753AbfANS5M (ORCPT ); Mon, 14 Jan 2019 13:57:12 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A786F653C2; Mon, 14 Jan 2019 18:57:11 +0000 (UTC) Received: from oldenburg2.str.redhat.com (ovpn-116-20.ams2.redhat.com [10.36.116.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6D0C15D9CA; Mon, 14 Jan 2019 18:57:05 +0000 (UTC) From: Florian Weimer To: Mathieu Desnoyers Cc: carlos , Joseph Myers , Szabolcs Nagy , libc-alpha , Thomas Gleixner , Ben Maurer , Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Will Deacon , Dave Watson , Paul Turner , Rich Felker , linux-kernel , linux-api Subject: Re: [RFC PATCH glibc 1/4] glibc: Perform rseq(2) registration at nptl init and thread creation (v4) References: <20181204192141.4684-1-mathieu.desnoyers@efficios.com> <87h8fkz6qx.fsf@oldenburg2.str.redhat.com> <1681283664.1380.1547152315426.JavaMail.zimbra@efficios.com> <1488546469.1564.1547169116539.JavaMail.zimbra@efficios.com> Date: Mon, 14 Jan 2019 19:57:03 +0100 In-Reply-To: <1488546469.1564.1547169116539.JavaMail.zimbra@efficios.com> (Mathieu Desnoyers's message of "Thu, 10 Jan 2019 20:11:56 -0500 (EST)") Message-ID: <87bm4j9if4.fsf@oldenburg2.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Mon, 14 Jan 2019 18:57:11 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Mathieu Desnoyers: > Now that I think about it, it's important to move the rseq registration > done at nptl init (in my current code) to some lower-level csu initialiation, > so applications that happen _not_ to link against libpthread also get > registered rseq for the main thread. Yes. In general, we want to avoid to force libraries which do not create threads to link against libpthread, and try to provide interfaces which are required for synchronization within libc. Thanks, Florian