From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout0.freenet.de ([195.4.92.90]:51851 "EHLO mout0.freenet.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754448Ab2JNPJ6 (ORCPT ); Sun, 14 Oct 2012 11:09:58 -0400 Message-ID: <507AD532.7000707@01019freenet.de> Date: Sun, 14 Oct 2012 17:07:30 +0200 From: Andreas Hartmann MIME-Version: 1.0 To: Alex Williamson , Bjorn Helgaas CC: "Roedel, Joerg" , Andreas Hartmann , kvm@vger.kernel.org, linux-pci Subject: Re: vfio: missing patch in linux 3.6 References: <506DA799.5090603@01019freenet.de> <1349364399.2759.42.camel@ul30vt.home> <20121004161421.GV4009@amd.com> <1349368080.2759.52.camel@ul30vt.home> <20121005130857.GX4009@amd.com> In-Reply-To: <20121005130857.GX4009@amd.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-pci-owner@vger.kernel.org List-ID: Roedel, Joerg wrote: > On Thu, Oct 04, 2012 at 10:28:00AM -0600, Alex Williamson wrote: >> 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. > > You can certainly do that, but for existing hardware (with an AMD IOMMU) > this check would never be true. These devices are always on a seperate > south-bridge chip which is connected to the north-bridge via PCIe. So > the topology where you find these devices is always the same in an AMD > IOMMU system. > >> 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? > > The device ids are kept the same to maintain compatability with older > software. Besides that, my statement about the peer-2-peer safety is > true for all south-bridges that you can find in an AMD IOMMU capable > system. http://news.gmane.org/find-root.php?group=gmane.linux.kernel.pci&article=16422 I think, Joerg wrote clearly that there is no problem any more to apply this patch. I run it since a long time meanwhile without any problem. Please, why aren't these patches applied? Thanks, kind regards, Andreas Hartmann