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=-0.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED 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 E1304C43441 for ; Fri, 14 Sep 2018 18:58:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6C1D120833 for ; Fri, 14 Sep 2018 18:58:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="vojrzXJG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C1D120833 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com 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 S1727865AbeIOANt (ORCPT ); Fri, 14 Sep 2018 20:13:49 -0400 Received: from smtp-fw-6001.amazon.com ([52.95.48.154]:38012 "EHLO smtp-fw-6001.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726748AbeIOANt (ORCPT ); Fri, 14 Sep 2018 20:13:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1536951482; x=1568487482; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=sA8qKkq54TsdfgA4cGgc3yjc0A30VSYglWhEoOYxjrk=; b=vojrzXJG2eGSo6dNND3BdMv052Rtmz8G154ti/Xt+LHIEleogZtdYYBJ lpRqifNLzai653PZqMGyx5yhMUGTrLl8e6tfjx7V+nyxIScZkRdW9yDhg lSufJ6YRaNduOsru+gJwlsNvcS5t3nmw7bQEXlgoOIHEOhew3NRei5NOy g=; X-IronPort-AV: E=Sophos;i="5.53,374,1531785600"; d="scan'208";a="357207084" Received: from iad6-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-2b-c300ac87.us-west-2.amazon.com) ([10.124.125.6]) by smtp-border-fw-out-6001.iad6.amazon.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 14 Sep 2018 18:58:00 +0000 Received: from EX13MTAUWB001.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan3.pdx.amazon.com [10.236.137.198]) by email-inbound-relay-2b-c300ac87.us-west-2.amazon.com (8.14.7/8.14.7) with ESMTP id w8EIvvVs100430 (version=TLSv1/SSLv3 cipher=AES256-SHA bits=256 verify=FAIL); Fri, 14 Sep 2018 18:57:59 GMT Received: from EX13D05UWB004.ant.amazon.com (10.43.161.208) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 14 Sep 2018 18:57:53 +0000 Received: from EX13MTAUWB001.ant.amazon.com (10.43.161.207) by EX13D05UWB004.ant.amazon.com (10.43.161.208) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 14 Sep 2018 18:57:53 +0000 Received: from localhost (10.85.19.144) by mail-relay.amazon.com (10.43.161.249) with Microsoft SMTP Server id 15.0.1367.3 via Frontend Transport; Fri, 14 Sep 2018 18:57:53 +0000 Date: Fri, 14 Sep 2018 11:57:53 -0700 From: Eduardo Valentin To: Greg Kroah-Hartman CC: Eduardo Valentin , , , Juergen Gross , Jan Beulich , Boris Ostrovsky Subject: Re: [PATCH 4.14 103/115] x86/xen: dont write ptes directly in 32-bit PV guests Message-ID: <20180914185753.GB9084@u40b0340c692b58f6553c.ant.amazon.com> References: <20180913131823.327472833@linuxfoundation.org> <20180913131829.701763608@linuxfoundation.org> <20180914171222.GA30580@u40b0340c692b58f6553c.ant.amazon.com> <20180914181927.GA20957@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20180914181927.GA20957@kroah.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 14, 2018 at 08:19:27PM +0200, Greg Kroah-Hartman wrote: > On Fri, Sep 14, 2018 at 10:12:22AM -0700, Eduardo Valentin wrote: > > Hello, > > > > On Thu, Sep 13, 2018 at 03:32:03PM +0200, Greg Kroah-Hartman wrote: > > > 4.14-stable review patch. If anyone has any objections, please let me know. > > > > > > ------------------ > > > > > > From: Juergen Gross > > > > > > commit f7c90c2aa4004808dff777ba6ae2c7294dd06851 upstream. > > > > > > In some cases 32-bit PAE PV guests still write PTEs directly instead of > > > using hypercalls. This is especially bad when clearing a PTE as this is > > > done via 32-bit writes which will produce intermediate L1TF attackable > > > PTEs. > > > > > > Change the code to use hypercalls instead. > > > > > > > Good that we got this in. Should we also take this one: > > b2d7a075a1cc ("x86/pae: use 64 bit atomic xchg function in native_ptep_get_and_clear") > > > > Which is under the line of the same issue? > > It's also in this patch series, the very next one in fact :) Cool! Missed that. Sorry for the noise. Thanks for including the patches! > > thanks, > > greg k-h > -- All the best, Eduardo Valentin