On Fri, Apr 15, 2022 at 06:45:34AM +0200, Christoph Hellwig wrote: > On Thu, Apr 14, 2022 at 03:46:03PM -0300, Jason Gunthorpe wrote: > > kvm and VFIO need to be coupled together however neither is willing to > > tolerate a direct module dependency. Instead when kvm is given a VFIO FD > > it uses many symbol_get()'s to access VFIO. > > > > Provide a single VFIO function vfio_file_get_ops() which validates the > > given struct file * is a VFIO file and then returns a struct of ops. > > > > Following patches will redo each of the symbol_get() calls into an > > indirection through this ops struct. > > So I got anoyed at this as well a while ago and I still think this > is the wrong way around. What I plan to do in future is to have differnt ops returned depending on if the file is a struct vfio_group or a struct vfio_device, so it is not entirely pointless like this. > I'd much rather EXPORT_SYMBOL_GPL kvm_register_device_ops and > just let kvm_vfio_ops live in a module than all the symbol_get > crazyness. We'll need to be careful to deal with unload races > or just not allow unloading, though. This is certainly more complicated - especially considering module unload - than a single symbol_get(). How do you see the benefit? Jason
