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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_NEOMUTT autolearn=unavailable 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 1DDDFC4360F for ; Fri, 5 Apr 2019 15:32:37 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 993CA21726 for ; Fri, 5 Apr 2019 15:32:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 993CA21726 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 44bP2V4rkTzDqVR for ; Sat, 6 Apr 2019 02:32:34 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=redhat.com (client-ip=209.132.183.28; helo=mx1.redhat.com; envelope-from=jpoimboe@redhat.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 44bP0g2yLlzDqLY for ; Sat, 6 Apr 2019 02:30:59 +1100 (AEDT) Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D00553082AFD; Fri, 5 Apr 2019 15:30:56 +0000 (UTC) Received: from treble (ovpn-123-87.rdu2.redhat.com [10.10.123.87]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CA39A60BFB; Fri, 5 Apr 2019 15:30:50 +0000 (UTC) Date: Fri, 5 Apr 2019 10:30:48 -0500 From: Josh Poimboeuf To: Randy Dunlap Subject: Re: [PATCH RFC 2/5] x86/speculation: Add support for 'cpu_spec_mitigations=' cmdline options Message-ID: <20190405153048.knaizips2n27fwtx@treble> References: <78c63cb08f36f55407f534d49cc2543079e44dbb.1554396090.git.jpoimboe@redhat.com> <20190405135712.GF23348@zn.tnic> <5ccc7515-33e6-b726-833e-9553ab0f4c6a@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <5ccc7515-33e6-b726-833e-9553ab0f4c6a@infradead.org> User-Agent: NeoMutt/20180716 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Fri, 05 Apr 2019 15:30:57 +0000 (UTC) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Heiko Carstens , Paul Mackerras , "H . Peter Anvin" , Ingo Molnar , Andrea Arcangeli , linux-s390@vger.kernel.org, x86@kernel.org, Will Deacon , Linus Torvalds , Catalin Marinas , Waiman Long , linux-arch@vger.kernel.org, Jon Masters , Jiri Kosina , Borislav Petkov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Tyler Hicks , Martin Schwidefsky , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, Apr 05, 2019 at 08:18:09AM -0700, Randy Dunlap wrote: > On 4/5/19 6:57 AM, Borislav Petkov wrote: > > On Thu, Apr 04, 2019 at 11:44:12AM -0500, Josh Poimboeuf wrote: > >> Configure x86 runtime CPU speculation bug mitigations in accordance with > >> the 'cpu_spec_mitigations=' cmdline options. This affects Meltdown, > >> Spectre v2, Speculative Store Bypass, and L1TF. > >> > >> The default behavior is unchanged. > >> > >> Signed-off-by: Josh Poimboeuf > >> --- > >> .../admin-guide/kernel-parameters.txt | 15 +++++++++ > >> arch/x86/include/asm/processor.h | 1 + > >> arch/x86/kernel/cpu/bugs.c | 32 ++++++++++++++++--- > >> arch/x86/kvm/vmx/vmx.c | 2 ++ > >> arch/x86/mm/pti.c | 4 ++- > >> 5 files changed, 49 insertions(+), 5 deletions(-) > >> > >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > >> index ac42e510bd6e..29dc03971630 100644 > >> --- a/Documentation/admin-guide/kernel-parameters.txt > >> +++ b/Documentation/admin-guide/kernel-parameters.txt > >> @@ -2552,6 +2552,11 @@ > >> > >> off > >> Disable all speculative CPU mitigations. > >> + Equivalent to: nopti [x86] > >> + nospectre_v2 [x86] > >> + spectre_v2_user=off [x86] > >> + spec_store_bypass_disable=off [x86] > >> + l1tf=off [x86] > >> > >> auto (default) > >> Mitigate all speculative CPU vulnerabilities, > >> @@ -2560,12 +2565,22 @@ > >> surprised by SMT getting disabled across kernel > >> upgrades, or who have other ways of avoiding > >> SMT-based attacks. > >> + Equivalent to: pti=auto [x86] > >> + spectre_v2=auto [x86] > >> + spectre_v2_user=auto [x86] > >> + spec_store_bypass_disable=auto [x86] > >> + l1tf=flush [x86] > >> > >> auto,nosmt > >> Mitigate all speculative CPU vulnerabilities, > >> disabling SMT if needed. This is for users who > >> always want to be fully mitigated, even if it > >> means losing SMT. > >> + Equivalent to: pti=auto [x86] > >> + spectre_v2=auto [x86] > >> + spectre_v2_user=auto [x86] > >> + spec_store_bypass_disable=auto [x86] > >> + l1tf=flush,nosmt [x86] > >> > >> mminit_loglevel= > >> [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this > > > > Yap, those sets look ok. > > nit: s/x86/X86/g > according to Documentation/admin-guide/kernel-parameters.rst Ah, I didn't realize I was conforming to a standard. I will update the other arch strings as well. Thanks. -- Josh