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It certainly > meets the standard required to show in-tree users. > >> When you have a complete open source driver stack which utilizes >> VFIO passthrough as the interface to communicate with the kernel >> drivers then we can eventually talk about that. > > That decision is not up to dmabuf Yes it is. This is the DMA-buf API which is added here. > - what VFIO subsystem requires to > accept a new UAPI is up to the VFIO maintainers. As far as I can see vfio-pci is used as a stub driver to avoid opening up the real driver. Upstreaming an API changes only makes sense if others can use it and this here is something completely special to this particular use case, without all components involved nobody else can use it. So as far as I can see that here is a no-go. But at the end of the day it's Linus who needs to say if that's ok or not, that's why I put him on CC. Regards, Christian. > DRM and VFIO have very different views on what is required to merge a > new uAPI. > > Jason