On Fri, 2012-02-24 at 14:34 +0100, Nicolas Cavallari wrote: > On 23/02/2012 19:51, Nicolas Cavallari wrote: > > On 23/02/2012 19:08, Christian Lamparter wrote: > >> On Thursday, February 23, 2012 06:27:59 PM Nicolas Cavallari wrote: > >>> On 23/02/2012 17:52, Christian Lamparter wrote: > >>>> On Thursday, February 23, 2012 04:53:34 PM Nicolas Cavallari wrote: > >>>>> While this seems to fix my problem, there could still be problems remaining > >>>>> in this code path. Particularly carl9170_tx_status will do lots of things > >>>>> like incrementing counters and waking up mac80211 queues... > >>>> That should be alright. As a rule of thumb, for every call to > >>>> carl9170_tx_accounting [called by carl9170_op_tx tx handler] > >>>> we need to call carl9170_tx_status. If the station is still in > >>>> ps mode, mac80211 will cache the station's frames and sets > >>>> the TIM bits. > >>> Part of the reason i wrote this, is because, while this patch fixes the > >>> memory accounting problem and prevent the AP from stopping working, the > >>> powersaving station sometimes cannot communicate with the AP anymore > >>> (other stations can). The station uses ath9k, and is just really doing a > >>> background scan. The first traces that i have just indicate that the > >>> station entered powersave mode, then sends probe requests and probe > >>> requests directed to the AP, then sends authentication requests to the > >>> AP (?), but the AP does not respond to any of them... > >>> > >> Do you run an 802.11n ap on carl9170? > > No, it's a 802.11g currently. > > My current wild guess is that, the responses to those requests are > > somehow still queued ... > > And i was right... > > /* > * Ignore doze->wake transitions that are > * indicated by non-data frames, the standard > * is unclear here, but for example going to > * PS mode and then scanning would cause a > * doze->wake transition for the probe request, > * and that is clearly undesirable. > */ > if (ieee80211_is_data(hdr->frame_control) && > !ieee80211_has_pm(hdr->frame_control)) > ap_sta_ps_end(sta); > > As (re)associations requests and Auth frames are not data frames, > mac80211 still considers that the station is still in powersave mode, so > it still queues frames, and even queues the responses to the auth > frames. Except that the station disassociated silently, and is trying to > re-associate after a short time. > > Shouldn't mac80211 transition the sta to "awake" when receiving > auth/assoc frames ? I don't think so, that would make us send frames to the station it no longer deserves to have. Hostapd should instead delete & re-create the station entry, I think? johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
