Hi, I'm just reporting that I'm getting basically the same error with hostapd on an Asus Tinkerboard, and building an image with the latest kernel (Armbian_5.76_Tinkerboard_Debian_stretch_next_4.19.26.img) doesn't seem to fix the problem. The only solution I have found is reverting back to the mainline kernel, but since I would like to use the spidev devices on the tinkerboard, it would be great if I didn't need to.
For reference, here is the journalctl output that mirrors the original post, but still occurring in an image I built yesterday.
Also, the current wifi driver seems to be r8723bs, which I'm not sure was addressed in your original fix.
Do I need to add a patch somewhere? I'm a kernel noob and not sure where to add the patch in the build directory, or what to even patch against in the linux kernel.