From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC0C5C31E46 for ; Wed, 12 Jun 2019 14:00:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70B0620B1F for ; Wed, 12 Jun 2019 14:00:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="G5YOtqFd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439566AbfFLOAQ (ORCPT ); Wed, 12 Jun 2019 10:00:16 -0400 Received: from mail.efficios.com ([167.114.142.138]:41738 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2439540AbfFLOAO (ORCPT ); Wed, 12 Jun 2019 10:00:14 -0400 Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 596B0249AED; Wed, 12 Jun 2019 10:00:12 -0400 (EDT) Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10032) with ESMTP id 6Lb4WZKRxa9k; Wed, 12 Jun 2019 10:00:12 -0400 (EDT) Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 02FA5249AE3; Wed, 12 Jun 2019 10:00:12 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 02FA5249AE3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=default; t=1560348012; bh=/7ujPEmKCbMtPLRlDvPpClTu5LXEic44ruUyrcVirq4=; h=Date:From:To:Message-ID:MIME-Version; b=G5YOtqFdFOujZTu7WHLmzKCD900izZdnPDZVu8Rm5ME/ERFd4Kh+OBjZ5f+qdyuZM 24hlYXxihIvEkpFpA2+u3FPaHonG384CdmeIJBMvfiQULOnqUBdU/USEboQ+RFTxan /ut8cgM3abBMJSdRF2x01DN0ufIir0ia6WOHEspEsJr7DfoBuylxPmjUfFtVyKWl2b 1bMOyDL+ZJxeWSgPY/klbgXkS4QkPXKUQECaDAxElSwc/swJRwAJDc2KBGMQx1Q9Mg R5TdSB9zjURzjd52/jh8Fi557U7eddrVejt818MAcvijsHnir3Ft+U0GYLpJxGsQ8Z 0V5mdeTbfpx/w== X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10026) with ESMTP id uCvd9gaxCDwI; Wed, 12 Jun 2019 10:00:11 -0400 (EDT) Received: from mail02.efficios.com (mail02.efficios.com [167.114.142.138]) by mail.efficios.com (Postfix) with ESMTP id D9A96249AD9; Wed, 12 Jun 2019 10:00:11 -0400 (EDT) Date: Wed, 12 Jun 2019 10:00:11 -0400 (EDT) From: Mathieu Desnoyers To: carlos , Florian Weimer Cc: 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 Message-ID: <914051741.43025.1560348011775.JavaMail.zimbra@efficios.com> In-Reply-To: References: <20190503184219.19266-1-mathieu.desnoyers@efficios.com> <732661684.21584.1559314109886.JavaMail.zimbra@efficios.com> <87muj2k4ov.fsf@oldenburg2.str.redhat.com> <1528929896.22217.1559326257155.JavaMail.zimbra@efficios.com> <87o93d4lqb.fsf@oldenburg2.str.redhat.com> <117220011.27079.1559663870037.JavaMail.zimbra@efficios.com> <87wohzorj0.fsf@oldenburg2.str.redhat.com> Subject: Re: [PATCH 1/5] glibc: Perform rseq(2) registration at C startup and thread creation (v10) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.142.138] X-Mailer: Zimbra 8.8.12_GA_3803 (ZimbraWebClient - FF67 (Linux)/8.8.12_GA_3794) Thread-Topic: glibc: Perform rseq(2) registration at C startup and thread creation (v10) Thread-Index: 6rG93gdkMSoHS5ZP168diTIrRPG9Cw== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- On Jun 10, 2019, at 4:43 PM, carlos carlos@redhat.com wrote: > On 6/6/19 7:57 AM, Florian Weimer wrote: >> Let me ask the key question again: Does it matter if code observes the >> rseq area first without kernel support, and then with kernel support? >> If we don't expect any problems immediately, we do not need to worry >> much about the constructor ordering right now. I expect that over time, >> fixing this properly will become easier. > > I just wanted to chime in and say that splitting this into: > > * Ownership (__rseq_handled) > > * Initialization (__rseq_abi) > > Makes sense to me. > > I agree we need an answer to this question of ownership but not yet > initialized, to owned and initialized. > > I like the idea of having __rseq_handled in ld.so. Very good, so I'll implement this approach. Sorry for the delayed feedback, I am traveling this week. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com