Hi Andrei & Stefano, On Thu, Jan 11, 2024 at 04:35:22PM -0800, Stefano Stabellini wrote: > Hi Andrei, > > Great that you are working with Xen and virtio. We at AMD are very > interested in it as well. > > I'll let Artem (CCed) and his team comment about the xen-troops > repository. > > I can share that from our side we are working toward adding complete > support for using QEMU as virtio-backends provider. Vikram (CCed) > managed to get virtio-net to work with the backend in QEMU. He should be > able to provide instructions. We want to get those patches upstream in > Xen and QEMU as soon as possible. Actually, QEMU patches are already upstreamed for virtio-blk and virtio-net devices available in v8.2.0. For virtio with grants, the patches are WiP.
On Xen side, we are yet to upstream xen-tools patches which basically generate the right arguments when invoking QEMU. Here are down stream patches if you want: 1. https://github.com/Xilinx/xen/commit/be35b46e907c7c78fd23888d837475eb28334638 2. For Virtio disk backend: https://github.com/Xilinx/xen/commit/947280803294bbb963f428423f679d074c60d632 3. For Virtio-net: https://github.com/Xilinx/xen/commit/32fcc702718591270e5c8928b7687d853249c882 4. For changing the machine name to Xenpvh(to align with QEMU changes): https://github.com/Xilinx/xen/commit/5f669949c9ffdb1947cb47038956b5fb8eeb072a > > The libxl changes are lagging behind a bit and you might have to use > device_model_args to enable virtio backends in QEMU. But QEMU 8.2.0 can still be used for virtio-net on ARM. @Andrei here is an example on how to use virtio-net with QEMU: -device virtio-net-device,id=nic0,netdev=net0,mac=00:16:3e:4f:43:05 \ -netdev type=tap,id=net0,ifname=vif1.0-emu,br=xenbr0,script=no,downscript=no\ -machine xenpvh Please make sure to use xenpvh as QEMU machine. Regards, Vikram > > For SCMI, I'll let Bertrand (CCed) comment. > > Cheers, > > Stefano > > > On Thu, 11 Jan 2024, Andrei Cherechesu (OSS) wrote: > > Hello, > > > > As I've mentioned in previous discussion threads in the xen-devel > > community, we are running Xen 4.17 (uprev to 4.18 in progress) on NXP > > S32G automotive processors (Cortex-A53 cores) and we wanted to know more > > about the support for various VirtIO device types in Xen. > > > > In the Xen 4.17 release notes, the VirtIO standalone backends mentioned > > as supported and tested are: virtio-disk, virtio-net, virtio-i2c and > > virtio-gpio. > > > > However, we've only managed to successfully set up and try some > > use-cases with the virtio-disk standalone backend [0] (which Olexandr > > provided) based on the virtio-mmio transport. > > > > As such, we have a few questions, which we haven't been able to figure > > out from the mailing list discussions and/or code: > > 1. Are there any plans for the virtio-disk repo to have a stable > > version? Is it going to be long-term hosted and maintained in the > > xen-troops github repo? Or was it just an one-time PoC implementation > > > > and the strategy for future VirtIO devices will be based on a more > > generic > > > > approach (i.e., without need for a specific standalone app)? > > > > > > 2. With regards to the other backends, we want to try out and provide PV > > > > networking to a DomU based on virtio-net, but we haven't found any > > available > > > > resources for it (e.g., the standalone backend implementation if needed > > for > > > > control plane, configuration examples, presentations, demos, docs). > > Does it > > > > rely on the QEMU virtio-net or vhost implementation? Are there any > > examples > > > > on how to set it up? Any required Xen/Linux Kernel/QEMU versions? > > > > > > 3. What other VirtIO device types are there planned to be supported in > > Xen? > > > > I'm supposing libxl will also need changes to accomodate new > > configuration > > > > parameters for each of them. Or is there something I'm missing? > > > > > > 4. Also, while we're at it, are there any plans regarding SCMI > > awareness for Xen (e.g., SCMI Mediator - where the RFC thread from 2022 > > > > seems discontinued)? Or is the preferred approach for sharing SCMI > > access > > > > to guests through virtio-scmi? > > > > Thank you very much for the support, once again, and we're also looking > > forward to the progress on the rust-vmm initiative. > > > > Regards, > > Andrei Cherechesu, > > NXP Semiconductors > > > > [0] https://github.com/xen-troops/virtio-disk > > > > > >
