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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 4C6B7C34047 for ; Wed, 19 Feb 2020 14:43:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1D84024656 for ; Wed, 19 Feb 2020 14:43:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="ndhB4WdC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726712AbgBSOn2 (ORCPT ); Wed, 19 Feb 2020 09:43:28 -0500 Received: from mail.skyhub.de ([5.9.137.197]:36210 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726582AbgBSOn2 (ORCPT ); Wed, 19 Feb 2020 09:43:28 -0500 Received: from zn.tnic (p200300EC2F095500AC4EBF6CAFE7BFD1.dip0.t-ipconnect.de [IPv6:2003:ec:2f09:5500:ac4e:bf6c:afe7:bfd1]) (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 1B5761EC0CD2; Wed, 19 Feb 2020 15:43:23 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1582123403; 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=R9S+fJZVrq50eOUEF8rI2ReG0g4IgbKjuDpJyo13/3Q=; b=ndhB4WdCd1C0ZRq2oXpWB2XKP5QMzeL088a1yk5T+moEorrOuGn2Nh3lNpwzND5OmEKkn1 GDFVkhdW8uvHTQ7jOgkpZIh/Fl2UHcMnVvGlj59JcUJS9roGbpmYse1rqRubEEF/23vKCb sTyXT2r7yLOSqUnhXxGOenE4jedPSp0= Date: Wed, 19 Feb 2020 15:43:18 +0100 From: Borislav Petkov To: Steven Rostedt Cc: Peter Zijlstra , Andy Lutomirski , Tony Luck , x86-ml , lkml Subject: Re: [RFC] #MC mess Message-ID: <20200219144318.GD30966@zn.tnic> References: <20200218173150.GK14449@zn.tnic> <20200219081541.GG14914@hirez.programming.kicks-ass.net> <20200219092115.3b3cccd9@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200219092115.3b3cccd9@gandalf.local.home> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 19, 2020 at 09:21:15AM -0500, Steven Rostedt wrote: > What would be nice is to have a NMI_IRET, that is defined as something > that wont break legacy CPUs. Where it could be just a nop iret, or maybe > if possible a "lock iret"? That is, not have a IRET_NON_NMI, as that > would be all over the place, but just the iret for NMI itself. As > that's in one place. You mean, we could keep the nested NMI thing but it won't practically get executed on NMI_IRET CPUs because there won't be any NMI nesting anymore? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette