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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 E5CBCC3A5A0 for ; Mon, 20 Apr 2020 20:27:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4D3E20782 for ; Mon, 20 Apr 2020 20:27:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587414478; bh=dyBm7I04/BcG1QP4G1MC3heldhpx4b6YSPyL7WyQfjo=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=XtTdFnWUdJ7AVhicAeW1mnI8q37iNFq6CS6h58Tn1WpobwgVGTxbgCqTs/mbxHQr+ g6kbIlvGoicOu5a0Fr5G86i1L9TL2dr/DfulRYJQMUZ1lW/OJMIZP14bbN8zEZWOUn aimfUgYei4ufikF9sXEAlUHx+o1rczCNnusXKQ6M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728378AbgDTU16 (ORCPT ); Mon, 20 Apr 2020 16:27:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725988AbgDTU15 (ORCPT ); Mon, 20 Apr 2020 16:27:57 -0400 Received: from mail-lj1-x241.google.com (mail-lj1-x241.google.com [IPv6:2a00:1450:4864:20::241]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E51CC061A0E for ; Mon, 20 Apr 2020 13:27:57 -0700 (PDT) Received: by mail-lj1-x241.google.com with SMTP id q19so11512689ljp.9 for ; Mon, 20 Apr 2020 13:27:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=7lXVFlCuhZRlNIKPWno7jyPJtjBUewfnSNmf8ZBkjkU=; b=cn88vqLJ3iqpfoPaMzWrtCIV4M8jcHhWWu71rGqbgTe5Q/UQn2kwB72nwO+wt0ZsxV Fe0cMAvboICZetRhUSad49xM+2KRg2LEkiMxaySpZdfmgaSTauF8lNCz7NT6nkAP+jvT GCDKi7YV6yK0o0sTidFCFjCHDaGmRz+vbXKJo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=7lXVFlCuhZRlNIKPWno7jyPJtjBUewfnSNmf8ZBkjkU=; b=B1JUrmwJaZNgZm7hxzqRVlOGuNr5mDaSR7x0JS47twt0FtuMCnQyWN3Fmyxhgmls0L xbAsrqMjTgtwYYnAKTOGRe6YNTk8x/x/VCRVl4VC+UFiPEvvcDLnjUEGm+utPEpDykq9 plz4m5xuj2aaeuEBRknHUFG0EpGIPtZgsKxqKeIMgxdLz/RDd95GGZoeNeDsNTHxMK4k eF47xQW4ltbXwZf5SfGwSC+C0d/ceID10lwEuxHwTU8+Ueqy1IPGawtQC+qRx2dC6VNp SVCv7Y55CaVp903UaHdbsMFuaYK+ZPPUQxNDAm/TjV8FvhdpXu7glU8wFD+hH5PMViEd /6+g== X-Gm-Message-State: AGi0PuZBskYQIOThi6Bop1Y4pOvO84eJUgPQUS1omZ1uH7zjhLiQOCmY Uvoz3XwHvtglRjHJsWdjWH5HkH+5kaY= X-Google-Smtp-Source: APiQypI1eBzbZHgMYGSKXRItjiBHH1WDoKfd8rSGYUx450dBurYhILTojmROYC6aDC50db3olpq5QQ== X-Received: by 2002:a05:651c:449:: with SMTP id g9mr11514232ljg.278.1587414474248; Mon, 20 Apr 2020 13:27:54 -0700 (PDT) Received: from mail-lf1-f46.google.com (mail-lf1-f46.google.com. [209.85.167.46]) by smtp.gmail.com with ESMTPSA id h21sm358838lfp.1.2020.04.20.13.27.52 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Apr 2020 13:27:53 -0700 (PDT) Received: by mail-lf1-f46.google.com with SMTP id 198so9178946lfo.7 for ; Mon, 20 Apr 2020 13:27:52 -0700 (PDT) X-Received: by 2002:a05:6512:405:: with SMTP id u5mr11369327lfk.192.1587414472376; Mon, 20 Apr 2020 13:27:52 -0700 (PDT) MIME-Version: 1.0 References: <67FF611B-D10E-4BAF-92EE-684C83C9107E@amacapital.net> <20200420202332.GA30160@agluck-desk2.amr.corp.intel.com> In-Reply-To: <20200420202332.GA30160@agluck-desk2.amr.corp.intel.com> From: Linus Torvalds Date: Mon, 20 Apr 2020 13:27:36 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] x86/memcpy: Introduce memcpy_mcsafe_fast To: "Luck, Tony" Cc: Dan Williams , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , X86 ML , stable , Borislav Petkov , "H. Peter Anvin" , Peter Zijlstra , Erwin Tsaur , Linux Kernel Mailing List , linux-nvdimm Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 20, 2020 at 1:23 PM Luck, Tony wrote: > > I think they do. If the result of the wrong data has already > been sent out the network before you process the signal, then you > will need far smarter application software than has ever been written > to hunt it down and stop the spread of the bogus result. Bah. That's a completely red herring argument. By "asynchronous" I don't mean "hours later". Make it be "interrupts are enabled, before serializing instruction". Yes, we want bounded error handling latency. But that doesn't mean "synchronous" Linus