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Now VFIO allows a migration to happen without this trick. I'm wondering whether all relevant NICs can also support VFIO migrations in the future, then we can drop this tricky feature for good.
Currently, VFIO migration requires a VFIO (PCI) variant driver implementing the specific ops for migration. Only a few NICs are supported. It's growing though and we should expect more in the future, specially entreprise grade NICs. Thanks, C.
