> -----Original Message----- > From: Hostap [mailto:hostap-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of > Jouni Malinen > Sent: Sunday, September 25, 2016 22:22 > To: Otcheretianski, Andrei <andrei.otcheretianski@xxxxxxxxx> > Cc: Arik Nemtsov <arik@xxxxxxxxxx>; hostap@xxxxxxxxxxxxxxxxxxx; Nemtsov, > ArikX <arikx.nemtsov@xxxxxxxxx> > Subject: Re: [PATCH 04/18] sched_scan: Restart pno/sched_scan on channel > list update > > On Mon, Sep 05, 2016 at 05:32:57PM +0300, andrei.otcheretianski@xxxxxxxxx > wrote: > > As the scan channels might need to change when the channel list has > > been updated by the kernel. > > > diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c @@ > > -3223,14 +3223,22 @@ static void wpa_supplicant_update_channel_list( > > free_hw_features(ifs); > > ifs->hw.modes = wpa_drv_get_hw_feature_data( > > ifs, &ifs->hw.num_modes, &ifs->hw.flags); > > - } > > > > - /* Restart sched_scan with updated channel list */ > > - if (wpa_s->sched_scanning) { > > - wpa_dbg(wpa_s, MSG_DEBUG, > > - "Channel list changed restart sched scan."); > > - wpa_supplicant_cancel_sched_scan(wpa_s); > > - wpa_supplicant_req_scan(wpa_s, 0, 0); > > + /* Restart pno/sched_scan with updated channel list */ > > + if (ifs->pno) { > > + wpas_stop_pno(ifs); > > + wpas_start_pno(ifs); > > + } else if (ifs->sched_scanning && !ifs->pno_sched_pending) { > > OK.. So this part looks straightforward.. > > > + /* > > + * simulate a timeout to restart it. reset the state > > + * to start from the beginning. > > + */ > > + wpa_dbg(ifs, MSG_DEBUG, > > + "Channel list changed restart sched scan."); > > + ifs->sched_scan_timed_out = 1; > > + wpa_s->prev_sched_ssid = NULL; > > + wpa_supplicant_cancel_sched_scan(ifs); > > While this does something else than the previous code. Could you please > clarify why this uses a simulated timeout to restart sched_scan? > The simulated timeout was to handle possible race where an ongoing scheduled scan has stopped asynchronously while trying to restart a new scheduled scan cycle. This is similar to what is done in wpa_supplicant_sched_scan_timeout(). > And is that "wpa_s->prev_sched_ssid = NULL" really supposed to use wpa_s > instead of ifs? I'd assume this was a missed change from moving to be within > the dl_list_for_each loop with ifs being the pointer to the specific interface > while wpa_s is pointing to the interface that received the channel list update > event. > That's a bug. I'll prepare a fixed version for the patch. Regards, Ilan. _______________________________________________ Hostap mailing list Hostap@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/hostap
