Comment 3 for bug 1795296

Though it is not material to the bug itself, Jay was able to determine *why* the traffic fails when both the interface and the bridge has the same IP address. I originally incorrectly suspected this was related to rp_filter.

An ARP request generates an INCOMPLETE ARP entry (Requested IP and requesting device) for the device selected to send the ARP request. When an ARP reply is received, the device that is associated with processing the reply is the one used to determine if the reply completes a valid INCOMPLETE request.

This means that the device that is used to send the ARP request must be the one that processes the ARP reply.

When generating outbound traffic an INCOMPLETE arp entry is created for the non-bridge version of the interface

Example expected "ip neigh show" output, trimmed for relevance:
10.1.1.1 dev bond1.246 INCOMPLETE # Note the association between the requested IP and the device

When the reply comes back, it is processed by br-bond1.246 and the ARP entry is thus not completed