Re: [PATCHv7 2/3] mac80211: add radar detection command/event

[Johannes Berg <johannes@sipsolutions.net>]

On Thu, 2013-01-31 at 17:31 +0100, Simon Wunderlich wrote:

> > > +void ieee80211_dfs_cac_timer_work(struct work_struct *work)
> > > +{
> > > +	struct delayed_work *delayed_work =
> > > +		container_of(work, struct delayed_work, work);
> > > +	struct ieee80211_sub_if_data *sdata =
> > > +		container_of(delayed_work, struct ieee80211_sub_if_data,
> > > +			     dfs_cac_timer_work);
> > > +
> > > +	rtnl_lock();
> > 
> > what part requires rtnl?
> > 
> ieee80211_vif_release_channel() calls __ieee80211_vif_release_channel()
> and has ASSERT_RTNL() before parsing the AP VLAN list.
> 
> cfg80211_radar_event() probably doesn't need it ... I should remove it
> from the rtnl lock, I guess?

Doesn't really matter, I was just wondering in general but the AP VLAN
list makes sense.

> > > +void ieee80211_radar_detected(struct ieee80211_vif *vif, gfp_t gfp)
> > > +{
> > > +	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
> > > +
> > > +	trace_api_radar_detected(sdata);
> > > +
> > > +	/* may happen to devices which have been added but are not up */
> > > +	if (!cfg80211_chandef_valid(&sdata->vif.bss_conf.chandef))
> > > +		return;
> > 
> > Huh, what does device and up have to do with that?
> > 
> 
> What I've tried:
>  * configure 2 SSIDs in hostapd, start it
>  * both wlan0 and wlan0-1 got created
>  * only wlan0 comes up, wlan0-1 was rejected because of missing channel combinations
>  * now I've injected a radar - which should be sent to wlan0 and wlan0-1
>  * wlan0 could send the event, but wlan0-1 had no bss configured and therefore no chandef
> 
> I can change this comment to "may happen to devices which have currently no BSS configured",
> maybe that it is not so confusing ...

Not sure I understand, how would the radar detected event come to an
interface that doesn't really exist for the driver?

johannes