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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 B1C24C43441 for ; Thu, 22 Nov 2018 21:17:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 52B2C20645 for ; Thu, 22 Nov 2018 21:17:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 52B2C20645 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de 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 S2438936AbeKWH7H (ORCPT ); Fri, 23 Nov 2018 02:59:07 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:49050 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727301AbeKWH7H (ORCPT ); Fri, 23 Nov 2018 02:59:07 -0500 Received: from p4fea46ac.dip0.t-ipconnect.de ([79.234.70.172] helo=nanos) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1gPwM5-0005CH-QE; Thu, 22 Nov 2018 22:17:45 +0100 Date: Thu, 22 Nov 2018 22:17:44 +0100 (CET) From: Thomas Gleixner To: Borislav Petkov cc: Josh Poimboeuf , Linus Torvalds , Linux List Kernel Mailing , the arch/x86 maintainers , Peter Zijlstra , Andrew Lutomirski , Jiri Kosina , thomas.lendacky@amd.com, Andrea Arcangeli , David Woodhouse , Andi Kleen , dave.hansen@intel.com, Casey Schaufler , "Mallick, Asit K" , "Van De Ven, Arjan" , jcm@redhat.com, longman9394@gmail.com, Greg KH , david.c.stewart@intel.com, Kees Cook , Tim Chen Subject: Re: [patch 01/24] x86/speculation: Update the TIF_SSBD comment In-Reply-To: <20181122175229.GD10365@zn.tnic> Message-ID: References: <20181121201430.559770965@linutronix.de> <20181121201722.337599561@linutronix.de> <20181121230450.k75e4ipdag73dayz@treble> <20181121230854.GH27559@zn.tnic> <20181122173004.fn4tqoclhcyibxff@treble> <20181122175229.GD10365@zn.tnic> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 22 Nov 2018, Borislav Petkov wrote: > On Thu, Nov 22, 2018 at 11:30:04AM -0600, Josh Poimboeuf wrote: > > But it does describe its purpose, especially in relation to the > > 'spectre_v2=' option. > > Sure, but the thing I'm proposing > > spectre_v2_task_isol= > > describes it more precisely, IMHO. :) > > I.e., "enable/disable spectre v2 task isolation". > > > Previously 'spectre_v2=' might have been more appropriately named > > 'spectre_v2_kernel=' because it only protected the kernel from Spectre > > v2 attacks. Now with these new patches, 'spectre_v2=on' will protect > > the entire system. > > Hmmm, crazy idea: can we extend the options of spectre_v2= nstead? > > spectre_v2=user_isolation,... > spectre_v2=kernel,... > spectre_v2=task_isolation,... > > and so on? > > This way we can do a couple of option switches in one go. That's results in a huge parser state space and changes the existing interface. We stay with the separate option. Thanks, tglx