From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH v2 1/3] iommu/virtio: Add topology description to virtio-iommu config space Date: Tue, 3 Mar 2020 09:02:23 -0500 Message-ID: <20200303090046-mutt-send-email-mst@kernel.org> References: <20200228172537.377327-1-jean-philippe@linaro.org> <20200228172537.377327-2-jean-philippe@linaro.org> <20200302161611.GD7829@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20200302161611.GD7829@8bytes.org> Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" To: Joerg Roedel Cc: Jean-Philippe Brucker , linux-pci@vger.kernel.org, virtualization@lists.linux-foundation.org, eric.auger@redhat.com, iommu@lists.linux-foundation.org, sebastien.boeuf@intel.com, jacob.jun.pan@intel.com, bhelgaas@google.com, robin.murphy@arm.com List-Id: virtualization@lists.linuxfoundation.org On Mon, Mar 02, 2020 at 05:16:12PM +0100, Joerg Roedel wrote: > On Fri, Feb 28, 2020 at 06:25:36PM +0100, Jean-Philippe Brucker wrote: > > This solution isn't elegant nor foolproof, but is the best we can do at > > the moment and works with existing virtio-iommu implementations. It also > > enables an IOMMU for lightweight hypervisors that do not rely on > > firmware methods for booting. > > I appreciate the enablement on x86, but putting the conmfiguration into > mmio-space isn't really something I want to see upstream. It's in virtio config space, not in mmio-space. With a PCI virtio-IOMMU device this will be in memory. > What is the > problem with defining an ACPI table instead? This would also make things > work on AARCH64 UEFI machines. > > Regards, > > Joerg