On Wed, 2011-06-08 at 07:37 -0700, wwguy wrote: > On Wed, 2011-06-08 at 04:07 -0700, Johannes Berg wrote: > > On Fri, 2011-05-13 at 15:56 -0700, Daniel Halperin wrote: > > > > > I'm running an experiment where a client connects to the AP (both HT > > > iwlagn devices), starts a large transfer that gets aggregation going, > > > disassociates, and then reassociates and restarts the transfer. > > > > > > When mac80211 stops the queue (as part of the client's disassocation > > > process), it goes into the following code: > > > > > > IWL_DEBUG_HT(priv, "Stopping a non empty AGG HW QUEUE\n"); > > > priv->stations[sta_id].tid[tid].agg.state = > > > IWL_EMPTYING_HW_QUEUE_DELBA; > > > spin_unlock_irqrestore(&priv->sta_lock, flags); > > > > > > but if the station is removed right away the packets stay in the > > > queue. Indeed, when the client reconnects, the packets are then > > > delivered! But then the queue gets stuck and the AP issues a firmware > > > reset, which doesn't actually get traffic flowing again. Below, > > > there's a log with IWL_DL_HT set. It may be something racy; adding > > > DL_INFO and DL_MAC80211 I haven't been able to reproduce the bug yet > > > in a few tries. > > > > > > I suspect this will also be a problem with P2P, and not just my klugey > > > use of AP mode. Any suggestions as to how to fix? > > > > Sorry I'm replying this late. I'm not sure what the best way to fix it > > would be, but it makes sense that this would happen. Maybe we can flush > > the aggregation queue (asking the ucode to drop all frames) when the > > station is removed, but I'm not sure how we'd do that -- Wey-Yi do you > > know if that's possible? > > > flush the queue might be a good solution, I was being told (I don't > remember who and when which is bad), the "tx flush" command is needed > especially for P2P > > btw, there are 2 type of "tx flush", flush all the frames in uCode, or > just flush the frames in specified queue. Right, but the flush seems to be implemented per FIFO and queue, so it's a bit confusing. In this case we should drop all frames out of the aggretgaiton queue. 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
