I in ovs br - ryu controller is configured on an int, the host I use python scapy sendp send packets to cirros instance, source address is my custom false IP

Ryu can receive, but the packet source address is the address of the gateway cirros, rather than false IP,
But when I use tcpdump caught IP is normal display, is my false IP,
I think may be I have a question of ryu listening,
This is probably what circumstance