The Linux kernel manipulates switches with three different operation structures: switchdev_ops, ethtool_ops, and netdev_ops. [4]
There are two data bases at work that may not play nicely with each other (bug?):
- switch address database (ageing of 300 seconds)
- bridge fdb [5]
That the one you then stated
?
The switch just switches packets among its downstream ports but does not route any packet. Anything not destined for a learned downstream port gets switched upstream to the CPU for kernel processing (routing); no need for the switch to learn about upstream ports (upstream ports are defined via the Device Tree).
In all likelihood it may be the case
unless the swtich chip is equipped with a WLan port, which the chip in TO is not (no physical connection/lane) and thus
Evidently the bridge fdb is aware of the WLan ports but the switch address database is not.
DSA / SWITCHDEV code is still evolving at kernel source development and may indeed exhibit some erroneous behaviour in some earlier kernel versions. Mind
[4] The switchdev driver model [LWN.net]
[5] https://github.com/torvalds/linux/blob/master/Documentation/networking/switchdev.txt