kern/57645: bridge does not work on raspberry pi

[sc.dying%gmail.com@localhost]

>Number:         57645
>Category:       kern
>Synopsis:       bridge does not work on raspberry pi
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Oct 07 09:25:00 +0000 2023
>Originator:     sc.dying%gmail.com@localhost
>Release:        NetBSD-10.99.9 (and 10.0)
>Organization:
>Environment:
System: raspberrypi,model-b
Architecture: earmv6hf
Machine: evbarm
>Description:
	bridge using ethernet dongles on raspberry pi does
	not work.
	On my testbed (see How-To-Repeat section), tcpdump shows
	only broadcast/multicast packets on both interfaces, but
	unicast packets are not observed.

>How-To-Repeat:
	The testbed consists of a NetBSD rpi (named A) with 2 usb
	ethernet devices and two hosts (B, C). In my case two RTL8152
	are connected to rpi1b.
	Configure A as a bridge, and make sure B and C are connected via A.
	ping, ping6, and arping from B to C are unreachable, and vice versa.

>Fix:
	I have no good idea.