• Jouni Malinen's avatar
    mac80211: Disable requests for new scans in AP mode · b7a530d8
    Jouni Malinen authored
    AP mode operations are seriously affected if mac80211 runs through a
    multi-second scan while the AP is trying to send Beacon frames on the
    operation channel. While this could be implemented in a way that does
    not cause too many problems, it is not very simple and will require
    synchronization with Beacon frame scheduling in the drivers (scan one
    channel at a time between Beacon frames). Furthermore, such scanning
    takes quite a bit longer time and existing userspace applications
    would be likely to timeout while waiting for the results.
    
    For now, just refuse requests for new scans (SIOCSIWSCAN) when in AP
    mode. In practice, this moves the rejection from iwl* drivers into
    mac80211 to make it apply to every mac80211-based driver.
    
    This issue shows up in associated stations getting disconnected when
    something (e.g., Network Manager) requests a scan while the interface
    is in AP mode. When doing this continuously (e.g., NM does it every 120
    seconds), the network gets close to useless.
    Signed-off-by: default avatarJouni Malinen <jouni.malinen@atheros.com>
    Acked-by: default avatarJohannes Berg <johannes@sipsolutions.net>
    Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
    b7a530d8
wext.c 28.8 KB