On Wed, Jan 07, 2015 at 05:50:11PM +0200, Eliad Peller wrote: > Radar detection can last indefinite time. There is no > point in deferring a scan request in this case - simply > return -EBUSY.
> diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c > @@ -505,7 +505,7 @@ static int __ieee80211_start_scan(struct > ieee80211_sub_if_data *sdata, > - if (local->scan_req) > + if (local->scan_req || ieee80211_is_radar_required(local)) > return -EBUSY; This seems to be breaking a hwsim test case sequence of ap_vht80plus80 followed by ap_vht80. In such a case, all the HT40 scans for ap_vht80 fail due to this added condition resulting in -EBUSY being returned every time. It looks like this happens even if I change ap_vht80 to use the same country code (US) as ap_vht80plus80, so the change in the country code does not explain this either. I'm not sure what is causing the issue here, but it looks like something in ap_vht80plus80 (i.e., an attempt to enable a channel combination that would require DFS on one of the 80 MHz segments) leaves behind state that makes ieee80211_is_radar_required(local) return true even when it shouldn't. DFS for 80+80 is not yet supported, so I'd assume this is somehow related to that. Anyway, I don't think mac80211 should behave in this way. -- Jouni Malinen PGP id EFC895FA -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
