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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, USER_AGENT_MUTT 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 28A29C43142 for ; Thu, 21 Jun 2018 22:11:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CEE7622496 for ; Thu, 21 Jun 2018 22:11:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="h1GrsWOU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CEE7622496 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933985AbeFUWLd (ORCPT ); Thu, 21 Jun 2018 18:11:33 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:59046 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933940AbeFUWLR (ORCPT ); Thu, 21 Jun 2018 18:11:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Lw6iQC4U0bPerWM08hnCpm4iR/9rVFXoaaf93W0Lz54=; b=h1GrsWOUjEoqlfcSey0g6lwSU 6CteLb9oEYoAZmgbJ3KOOi4gEHUcvPLP7kLPaeatV1HElJWIXiOTqbac3KXbtSZmuHvk1jXjgkoJX JY1bpGQy2v/jcXODqkoLLApP/F9VCtvLdMCfBdslq4BLZxsmwbS5lxJRcKtKs/pjoSLjXdzU3NVmC N+LSYxOtNeF3lu9SW+GgNiNlzYa2annJZSk6Z+RQao+z4/Nw09aVlDIlbGIye83e160YN1V9+eUEY 2FBwmGBG7IwcIh1teQ9skzrr/oR6Sh/rtwK38Hb3IKh/PtByroY9KGTAK0uhrZVmpSj/4gGoDIKRn KTAyU7T2Q==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fW7nP-0001Zu-LF; Thu, 21 Jun 2018 22:11:15 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 282FA2029F1D7; Fri, 22 Jun 2018 00:11:14 +0200 (CEST) Date: Fri, 22 Jun 2018 00:11:14 +0200 From: Peter Zijlstra To: Fenghua Yu Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Ashok Raj , Dave Hansen , Rafael Wysocki , Tony Luck , Alan Cox , Ravi V Shankar , Arjan van de Ven , linux-kernel , x86 Subject: Re: [RFC PATCH 00/16] x86/split_lock: Enable #AC exception for split locked accesses Message-ID: <20180621221114.GD2494@hirez.programming.kicks-ass.net> References: <1527435965-202085-1-git-send-email-fenghua.yu@intel.com> <20180621193738.GA13636@worktop.programming.kicks-ass.net> <20180621201851.GC114883@romley-ivt3.sc.intel.com> <20180621220003.GD114883@romley-ivt3.sc.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180621220003.GD114883@romley-ivt3.sc.intel.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 21, 2018 at 03:00:03PM -0700, Fenghua Yu wrote: > The control knob for user is to choose killing the process (default) or > re-executing the faulting instruction without blocking the process. > Re-executing the instruction maybe be useful in platforms that run > well controlled apps with less split locks. Just fix the applications. I doubt there will be many, many other platforms will already SIGBUS on unaligned access, atomic or not.