From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: vfio: missing patch in linux 3.6 Date: Thu, 04 Oct 2012 10:28:00 -0600 Message-ID: <1349368080.2759.52.camel@ul30vt.home> References: <506DA799.5090603@01019freenet.de> <1349364399.2759.42.camel@ul30vt.home> <20121004161421.GV4009@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Andreas Hartmann , kvm@vger.kernel.org, Bjorn Helgaas , linux-pci To: "Roedel, Joerg" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:33689 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422730Ab2JDQ2G (ORCPT ); Thu, 4 Oct 2012 12:28:06 -0400 In-Reply-To: <20121004161421.GV4009@amd.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, 2012-10-04 at 18:14 +0200, Roedel, Joerg wrote: > On Thu, Oct 04, 2012 at 09:26:39AM -0600, Alex Williamson wrote: > > On Thu, 2012-10-04 at 17:13 +0200, Andreas Hartmann wrote: > > > Hello Alex, > > > > > > I just tested vfio as part of linux 3.6 and detected, that it doesn't > > > work because of the following missing patch: > > > > > > http://news.gmane.org/find-root.php?group=gmane.linux.kernel.pci&article=16422 > > > > > > Could you please get it applied for the next stable release? > > > > Hi Andreas, > > > > This patch needs to go through Bjorn's PCI tree, but as noted in the > > comments I have some outstanding questions that need to be answered, > > probably by Joerg. Thanks, > > What are the open questions? I have confirmation from the hardware > people that the south bridges are peer-2-peer safe. Other questions? Hi Joerg, There are a couple questions in the link above. Since the devices don't expose a PCIe capability, we probably need to add a check to look at the upstream device and verify we're not on a legacy bus where ACS can't be enforced. Then there's the general question of whether the confirmation of no peer-to-peer applies to every case where we might see this device (some of them seem to have history that pre-dates this specific package implementation) or do we need to try to identify specific package properties in addition to just a device ID? Thanks, Alex