ACS - Passive Scans - EBUSY

[Usman S]

Hi,

I have two wlan interfaces exposed from my wifi driver wherein one of
them is used as managed and the other one as master. Both of these are
controlled by two different applications (of course via wpa_supplicant
and hostapd). The problem arises when the station mode is already
scanning and there is a request to perform ACS via hostapd. It
receives an error -EBUSY as there is already a scan being performed.

Therefore hostapd fails to configure the AP as ACS failed. I quickly
skimmed through the acs.h and I dont see any error handling when there
is such failure. How to handle these situations? I dont want to look
at the wpa_supplicant state before triggering ACS but something could
be handled from nl80211 subsystem i.e., does it say that a scan is
already in progress. Could you please recommend on such situations.

Best Regards,
Usman