Drivers that set IEEE80211_HW_TIMING_BEACON_ONLY need to know when the DTIM will be sent. For that purpose, mac80211 sends to the low level driver all the data needed by the low level driver to determine the TBTT of the DTIM: The TSF, the DTIM count and the device clock of one beacon. If the low level driver knows the dtim period, it will be able to know the TBTT of the next DTIM. When we associate to an access point, we usually scan first and get probe responses. Based on the probe responses, we start to associate. If the device needs to configure the TBTT of the next DTIM (IEEE80211_HW_TIMING_BEACON_ONLY is set), mac80211 will wait until it hears a beacon and then give the aforementioned data to the low level driver. This case works fine. A less common case is a case in which we hear a beacon before we even start to associate. In this case, mac80211 already has all the data needed by the low level driver and all the data is sent straight away in the first bss_info_changed call. In that specific flow, the setting of the dtim_period was missing. iwlmvm needs this data and will fail the connection unless it is given the dtim_period within 300ms after the association. The following print would appear: iwlwifi: No association and the time event is over already... This led to disconnections. This patch fixes: https://bugzilla.kernel.org/show_bug.cgi?id=78101 Cc: <stable@xxxxxxxxxxxxxxx> [3.10+] Fixes: ef429dadf33f ("mac80211: introduce beacon-only timing data") Reported-by: Johannes Stezenbach <js@xxxxxxxxx> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx> --- v2: typos in commit message --- net/mac80211/mlme.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index e37b97d..661dc8b 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -4438,6 +4438,8 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata, sdata->vif.bss_conf.sync_device_ts = bss->device_ts_beacon; sdata->vif.bss_conf.sync_dtim_count = dtim_count; + sdata->vif.bss_conf.dtim_period = + ifmgd->dtim_period ? : 1; } } else { assoc_data->timeout = jiffies; -- 1.8.1.msysgit.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html