On Thu, 2013-02-07 at 19:38 +0100, Simon Wunderlich wrote:
> To remove the dependency to rtnl_lock() for
> ieee80211_vif_use/release_channel in AP mode, protect the AP_VLAN
> list with local->iflist_mtx instead.
>
> RTNL can not be used from within mac80211 workers, but the
> DFS AP interface requires to release channels (after DFS channel
> availability checks).
I have to say ... I don't like this churn.
> @@ -934,12 +936,14 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
> */
> sdata->control_port_protocol = params->crypto.control_port_ethertype;
> sdata->control_port_no_encrypt = params->crypto.control_port_no_encrypt;
> + mutex_lock(&sdata->local->iflist_mtx);
> list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
> vlan->control_port_protocol =
> params->crypto.control_port_ethertype;
> vlan->control_port_no_encrypt =
> params->crypto.control_port_no_encrypt;
> }
> + mutex_unlock(&sdata->local->iflist_mtx);
>
> sdata->vif.bss_conf.beacon_int = params->beacon_interval;
> sdata->vif.bss_conf.dtim_period = params->dtim_period;
> @@ -972,8 +976,10 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
> ieee80211_bss_info_change_notify(sdata, changed);
>
> netif_carrier_on(dev);
> + mutex_lock(&sdata->local->iflist_mtx);
> list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
> netif_carrier_on(vlan->dev);
> + mutex_unlock(&sdata->local->iflist_mtx);
Things like this are also questionable -- it still only works because
the RTNL is there.
I'm not sure what the solution would be though -- maybe allowing/using
both locks.
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
