From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH v6 0/7] Add virtio-iommu driver Date: Wed, 19 Dec 2018 18:09:59 -0500 Message-ID: <20181219180417-mutt-send-email-mst@kernel.org> References: <20181211182104.18241-1-jean-philippe.brucker@arm.com> <20181212103545.GV16835@8bytes.org> <9110873f-d344-b6b9-c722-9accfc329db2@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Return-path: Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Content-Disposition: inline In-Reply-To: <9110873f-d344-b6b9-c722-9accfc329db2@arm.com> To: Jean-Philippe Brucker Cc: Joerg Roedel , "iommu@lists.linux-foundation.org" , "linux-pci@vger.kernel.org" , "devicetree@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "virtio-dev@lists.oasis-open.org" , "jasowang@redhat.com" , "robh+dt@kernel.org" , Mark Rutland , "bhelgaas@google.com" , "frowand.list@gmail.com" , "kvmarm@lists.cs.columbia.edu" , "eric.auger@redhat.com" , "tnowicki@caviumnetworks.com" , "kevin.tian@intel.com" , Marc Zyngier , Robin Murphy List-Id: devicetree@vger.kernel.org On Thu, Dec 13, 2018 at 12:50:29PM +0000, Jean-Philippe Brucker wrote: > >> [3] git://linux-arm.org/linux-jpb.git virtio-iommu/v0.9.1 > >>     git://linux-arm.org/kvmtool-jpb.git virtio-iommu/v0.9 > > > > Unfortunatly gitweb seems to be broken on linux-arm.org. What is missing > > in this patch-set to make this work on x86? > > You should be able to access it here: > http://www.linux-arm.org/git?p=linux-jpb.git;a=shortlog;h=refs/heads/virtio-iommu/devel > > That branch contains missing bits for x86 support: > > * ACPI support. We have the code but it's waiting for an IORT spec > update, to reserve the IORT node ID. I expect it to take a while, given > that I'm alone requesting a change for something that's not upstream or > in hardware. Frankly I think you should take a hard look at just getting the data needed from the PCI device itself. You don't need to depend on virtio, it can be a small driver that gets you that data from the device config space and then just goes away. If you want help with writing such a small driver let me know. If there's an advantage to virtio-iommu then that would be its portability, and it all goes out of the window because of dependencies on ACPI and DT and OF and the rest of the zoo. > * DMA ops for x86 (see "HACK" commit). I'd like to use dma-iommu but I'm > not sure how to implement the glue that sets dma_ops properly. > > Thanks, > Jean OK so IIUC you are looking into Christoph's suggestions to fix that up? There's still a bit of time left before the merge window, maybe you can make above changes. -- MST