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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 436C3C433F5 for ; Mon, 7 Feb 2022 21:20:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238298AbiBGVU2 (ORCPT ); Mon, 7 Feb 2022 16:20:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238009AbiBGVUY (ORCPT ); Mon, 7 Feb 2022 16:20:24 -0500 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6D3E1C06173B for ; Mon, 7 Feb 2022 13:20:24 -0800 (PST) Received: from zn.tnic (dslb-088-067-221-104.088.067.pools.vodafone-ip.de [88.67.221.104]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id E5A851EC0354; Mon, 7 Feb 2022 22:20:18 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1644268819; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=CYC/XprXxlLjtCSDTCZqFLi9fh8jP1dSac6rxXbSPk4=; b=fU1lWmvzCg69qwsNYNKlDaDvwmjKJUgL9a/luch7eyALhUviHyTgfvMsAWaXa1U4Pqp/CC l7qB4AEbN8UWRoZI9+AL0RMmesnkE7/zwz06nPtHnHsuz9vHcuThbk0cv3VqpbFImrs6gg yYm1ZzVk6JP4jggO9RJTXbdO6SvquIo= Date: Mon, 7 Feb 2022 22:20:13 +0100 From: Borislav Petkov To: "Luck, Tony" Cc: Jue Wang , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "patches@lists.linux.dev" Subject: Re: [RFC] x86/mce: Add workaround for SKX/CLX/CPX spurious machine checks Message-ID: References: <20220207043640.2829295-1-juew@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 07, 2022 at 09:07:05PM +0000, Luck, Tony wrote: > Yes. That would work. It's an extra MSR read instead of a memory read. > But this isn't a performance path. Exactly. > The erratum has made its way through to the public specification > update yet :-( You mean "has not"? In any case, I guess you could say something like: pr_err_once("Erratum #XXX detected, disabling fast string copy instructions.\n"); or so and people can search with the erratum number later where the doc will explain it in more detail. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette