anchor.diff:    irq-handler-function
     (irq-latch (make-latch "Virtio-Block IRQ Notifier"))
     request-phys
  -  request-virt)
  +  request-virt
  +  scanout
  +  width
  +  height)
   
   (defun virtio-gpu-command-address (gpu &optional (offset 0))
     (+ (virtio-gpu-request-virt gpu)
  
positive.code:         (sys.int::memref-unsigned-byte-32 (virtio-gpu-command-address gpu +virtio-gpu-transfer-to-host-2d-y+) 0) y
          (sys.int::memref-unsigned-byte-32 (virtio-gpu-command-address gpu +virtio-gpu-transfer-to-host-2d-width+) 0) w
          (sys.int::memref-unsigned-byte-32 (virtio-gpu-command-address gpu +virtio-gpu-transfer-to-host-2d-height+) 0) h
          (sys.int::memref-unsigned-byte-32 (virtio-gpu-command-address gpu +virtio-gpu-transfer-to-host-2d-offset+) 0) 0
          (sys.int::memref-unsigned-byte-32 (virtio-gpu-command-address gpu +virtio-gpu-transfer-to-host-2d-resource-id+) 0) +virtio-gpu-framebuffer-resource-id+)
    (virtio-gpu-issue-command gpu +virtio-gpu-transfer-to-host-2d-size+ 0 in-unsafe-context-p)
    (virtio-gpu-configure-command gpu
  
negative.code:             (when (not successp)
                (debug-print-line "virtio-gpu: Unable to set scanout: " error)
              (return-from virtio-gpu-register nil)))
            (setf (virtio-gpu-scanout gpu) pmode
                  (virtio-gpu-width gpu) width
                  (virtio-gpu-height gpu) height)
            (video-set-framebuffer framebuffer-phys width height
                                   (* width 4) :x8r8g8b8
                                   (lambda (x y w h in-unsafe-context-p)
  