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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 5CA45C43219 for ; Wed, 1 May 2019 14:49:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 23858208C3 for ; Wed, 1 May 2019 14:49:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726714AbfEAOtu (ORCPT ); Wed, 1 May 2019 10:49:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49598 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726673AbfEAOtu (ORCPT ); Wed, 1 May 2019 10:49:50 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6AA7EC024915; Wed, 1 May 2019 14:49:49 +0000 (UTC) Received: from llong.remote.csb (dhcp-17-85.bos.redhat.com [10.18.17.85]) by smtp.corp.redhat.com (Postfix) with ESMTP id E30A710021B4; Wed, 1 May 2019 14:49:44 +0000 (UTC) Subject: Re: [RFC PATCH v9 03/13] mm: Add support for eXclusive Page Frame Ownership (XPFO) To: Khalid Aziz , Ingo Molnar Cc: juergh@gmail.com, tycho@tycho.ws, jsteckli@amazon.de, keescook@google.com, konrad.wilk@oracle.com, Juerg Haefliger , deepa.srinivasan@oracle.com, chris.hyser@oracle.com, tyhicks@canonical.com, dwmw@amazon.co.uk, andrew.cooper3@citrix.com, jcm@redhat.com, boris.ostrovsky@oracle.com, iommu@lists.linux-foundation.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-security-module@vger.kernel.org, Khalid Aziz , Linus Torvalds , Andrew Morton , Thomas Gleixner , Andy Lutomirski , Peter Zijlstra , Dave Hansen , Borislav Petkov , "H. Peter Anvin" , Arjan van de Ven , Greg Kroah-Hartman References: <20190417161042.GA43453@gmail.com> From: Waiman Long Organization: Red Hat Message-ID: <35c4635e-8214-7dde-b4ec-4cb266b2ea10@redhat.com> Date: Wed, 1 May 2019 10:49:44 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Wed, 01 May 2019 14:49:50 +0000 (UTC) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Wed, Apr 03, 2019 at 11:34:04AM -0600, Khalid Aziz wrote: > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 858b6c0b9a15..9b36da94760e 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -2997,6 +2997,12 @@ > >      nox2apic    [X86-64,APIC] Do not enable x2APIC mode. > > +    noxpfo        [XPFO] Disable eXclusive Page Frame Ownership (XPFO) > +            when CONFIG_XPFO is on. Physical pages mapped into > +            user applications will also be mapped in the > +            kernel's address space as if CONFIG_XPFO was not > +            enabled. > + >      cpu0_hotplug    [X86] Turn on CPU0 hotplug feature when >              CONFIG_BO OTPARAM_HOTPLUG_CPU0 is off. >              Some features depend on CPU0. Known dependencies are: Given the big performance impact that XPFO can have. It should be off by default when configured. Instead, the xpfo option should be used to enable it. Cheers, Longman