From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751790AbdILPqB (ORCPT ); Tue, 12 Sep 2017 11:46:01 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:21388 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751740AbdILPp4 (ORCPT ); Tue, 12 Sep 2017 11:45:56 -0400 Subject: Re: [PATCH 2/4] xen: limit grant v2 interface to the v1 functionality To: Juergen Gross , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org References: <20170908144849.2958-1-jgross@suse.com> <20170908144849.2958-3-jgross@suse.com> From: Boris Ostrovsky Message-ID: Date: Tue, 12 Sep 2017 11:44:41 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170908144849.2958-3-jgross@suse.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/08/2017 10:48 AM, Juergen Gross wrote: > As there is currently no user for sub-page grants or transient grants > remove that functionality. This at once makes it possible to switch > from grant v2 to grant v1 without restrictions, as there is no loss of > functionality other than the limited frame number width related to > the switch. But isn't that ABI violation? v2 is expected to support this (XSAs notwithstanding) -boris