wpa_supplicant seems to prefer 2.4GHz over 5GHz

[John Frankish]

Ref: https://bugzilla.kernel.org/show_bug.cgi?id=175401

I've been trying to figure out why Windows seems to connect to my WAP at a faster speed than Linux on the same machine in the same physical location.

No matter if the 5GHz signal strength is greater than or less than the 2.4GHz signal strength, wpa_supplicant always seems to connect to the 2.4GHz signal. Conversely, Windows seems preferentially to connect to the 5GHz signal.

I've found that, if I force wpa_supplicant to connect to the 5GHz signal using "freq_list=5240" in the conf file, (and disable power saving) then I do get a similar throughput in Linux compared to Windows as measured with iperf.

Does anybody know why wpa_supplicant seems to prefer 2.4GHz to 5GHz?

What does wpa_supplicant use to decide which frequency to connect to?

[Using a Cisco WAP371, linux-4.2.9, Intel Dual Band Wireless AC 7260, wpa_supplicant-2.5]

Regards
John