virtio "transitional devices"?

[Alexander von Gluck IV]

Could someone explain to me what virtio "transitional devices" are?

https://docs.oasis-open.org/virtio/virtio/v1.1/cs01/virtio-v1.1-cs01.html#x1-1020002

Are "Transitional devices" pre-1.0 specification?

Haiku's virtio driver (PCI) is looking for PCIID Devices 0x1000-0x103F


I've noticed qemu-6.1.0 has begun to offer PCI DeviceID  0x1040-0x107F to
the operating system breaking our virtio drivers.

Expanding our search range to 0x1040+ seems to solve the issues and gives
us a working virtio driver, but I feel like we should be checking for
other differences.

Has something changed in recent qemu's around virtio?  I don't see anything
documented in the release notes.

 -- Alex