On 7/8/2025 4:16 PM, Johannes Berg wrote:
On Wed, 2025-06-25 at 18:31 +0530, Aditya Kumar Singh wrote:- if (ieee80211_num_beaconing_links(sdata) && - (!(wiphy->features & NL80211_FEATURE_AP_SCAN) || - !(req->flags & NL80211_SCAN_FLAG_AP))) - return -EOPNOTSUPP; + for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; + link_id++) { + link = sdata_dereference(sdata->link[link_id], sdata); + if (!link) + continue;for_each_link_data()
Sure. When I was writing this, this macro was not present hence did not use it. Now that it is there, I will use it. Thanks for pointing it out.
+ + /* if the link is not beaconing, ignore it */ + if (!sdata_dereference(link->u.ap.beacon, sdata)) + continue; + + /* If we are here then at least one of the link is + * beaconing and since radio level information is + * not present or single underlying radio is present, + * no point in checking further and hence return if + * flag requirements are not met. + */ + if (wiphy->n_radio < 2) { + if (!(wiphy->features & NL80211_FEATURE_AP_SCAN) || + !(req->flags & NL80211_SCAN_FLAG_AP)) + return -EOPNOTSUPP; + + continue; + }Is that _really_ worth special-casing in the scan control path? It's not like this is a performance question here. Maybe ieee80211_is_radio_idx_in_scan_req() shouldn't WARN_ON() then or something, so we can reuse it. Or maybe (better?) just reorder the checks there, if the chan_radio_idx==-1 and radio_idx==-1 would return first, and WARN only if we found a scan channel that isn't covered by a radio?
sure reordering seems much better. Thanks for the suggestion, will change.
And <2 seems really strange anyway, ==1 should basically never happen, it's equivalent to ==0, as in no list of radios?
That is correct. If underlying wiphy does not advertise, it would be 0. And if it advertises, ideally it should be 2 or more (otherwise why advertising?) But, there is no check for 1. So a radio can choose to advertise but keep n_radios as 1. And having n_radio 1 is also same as not advertising it. Hence to ensure these kicks in only when we know n_radios is greater than 1, < 2 is checked. Same way other two places also it is used.
-- Aditya
