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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS 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 09146C04AA7 for ; Mon, 13 May 2019 15:57:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CCBB52147A for ; Mon, 13 May 2019 15:57:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="LlxuNk4L" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730053AbfEMP5x (ORCPT ); Mon, 13 May 2019 11:57:53 -0400 Received: from aserp2130.oracle.com ([141.146.126.79]:49958 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728268AbfEMP5x (ORCPT ); Mon, 13 May 2019 11:57:53 -0400 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x4DFs1hJ072718; Mon, 13 May 2019 15:55:54 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=IDGztZNSk3EOeDwS/6bGjcJdmBuu3X/lohbpa7Ehouo=; b=LlxuNk4Ll9o+8qngaWj0VqzCQgTsSXzex1axGc7UkNh6H5gn9YstC9amPWxaaDjGAGxy Sxa/tWIucIiMuDc5eNs8xpePwQDo9RjRHZDlx4gteU7+7qD3qJfcGlJ8jfI4p0KU2bXF hTrOvWE9u4F+yBZzqkpFK8w/hbkYVOGGj1HI167yYV1YLAZhrm+AGaMuoc32h1acCEu+ Sl+LCkuMuGLucQ66wPTJ9InxMzlRKZsSsAsH/9IxUOkunfxL+CHBTWsawzGKlt1dVVMx tOIPcxxVfu7ZL49L746BHIKd3GBFDSYj5TXX0IQIUKLyuedXoNGVX6/hX8WvrZ3cNXni Fw== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2130.oracle.com with ESMTP id 2sdkwdg710-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 13 May 2019 15:55:54 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x4DFtFss087063; Mon, 13 May 2019 15:55:53 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3030.oracle.com with ESMTP id 2sdmeajnva-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 13 May 2019 15:55:53 +0000 Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x4DFtmTB016531; Mon, 13 May 2019 15:55:49 GMT Received: from [10.166.106.34] (/10.166.106.34) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 13 May 2019 08:55:48 -0700 Subject: Re: [RFC KVM 02/27] KVM: x86: Introduce address_space_isolation module parameter To: Andy Lutomirski Cc: Paolo Bonzini , Radim Krcmar , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Peter Zijlstra , kvm list , X86 ML , Linux-MM , LKML , Konrad Rzeszutek Wilk , jan.setjeeilers@oracle.com, Liran Alon , Jonathan Adams References: <1557758315-12667-1-git-send-email-alexandre.chartre@oracle.com> <1557758315-12667-3-git-send-email-alexandre.chartre@oracle.com> From: Alexandre Chartre Organization: Oracle Corporation Message-ID: <1c541cde-a502-032a-244b-96e110507224@oracle.com> Date: Mon, 13 May 2019 17:55:44 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9256 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905130109 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9256 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905130109 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/13/19 5:46 PM, Andy Lutomirski wrote: > On Mon, May 13, 2019 at 7:39 AM Alexandre Chartre > wrote: >> >> From: Liran Alon >> >> Add the address_space_isolation parameter to the kvm module. >> >> When set to true, KVM #VMExit handlers run in isolated address space >> which maps only KVM required code and per-VM information instead of >> entire kernel address space. > > Does the *entry* also get isolated? If not, it seems less useful for > side-channel mitigation. > Yes, context is switched before VM entry. We switch back to kernel address space if VM-exit handler needs it or when exiting the KVM_RUN ioctl. alex.