On Wed, Feb 24, 2021 at 04:26:43PM +0800, Jason Wang wrote: > Basically on first guest access QEMU would tell kernel whether > guest is using the legacy or the modern interface. > E.g. virtio_pci_config_read/virtio_pci_config_write will call > ioctl(ENABLE_LEGACY, 1) > while virtio_pci_common_read will call ioctl(ENABLE_LEGACY, 0) > > > But this trick work only for PCI I think? > > Thanks
ccw has a revision it can check. mmio does not have transitional devices at all. -- MST
