Hello list, Context: I am using one device in AP mode, the other in client mode. The client uses wpa_supplicant to do *background scan to other channels that the data channel*. I am running iperf (UDP) *from the AP* to the client. My device is Cavium development board-based (Octeon III CPU), equipped with Compex WLE350NX. It used to work correctly with kernel 3.18 and an old 2015 wireless backport. Now I updated to kernel 4.9 and the wireless backport 4.19.32-1, the last one from the OpenWRT trunk. (previously I used backport-2017-11-01 with the same failure). I am running wireshark with Airpcap to spy the wireless link. Problem: When the client scans offchannel, it correctly sends nullfunc frames around the offchannel period, with the PM bit set then unset. However, during this time, the AP continues to send data to the client. This results in a lot of lost frames, though I set the powersave buffers to high values on the AP side. After some research I saw that the same kind of problem was fixed [1] and even re-fixed, but since there where so many changes in the queue management, I cannot really compare his work and the current state of the driver. Any idea / patch / directions of research ? J.P. Tosoni - ACKSYS [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5519541d5a5f19893546883547e2f0f2e5934df7
