On 3/12/2025 1:55 AM, Johannes Berg wrote:
Hi Aloka, all,
+ * @NL80211_MBSSID_CONFIG_ATTR_TX_LINK_ID: Link ID of the transmitted profile.
+ * This parameter is mandatory if the transmitted profile is part of an MLD
+ * and the interface getting configured is a non-transmitted profile. For all
+ * other cases it will be ignored.
So I guess it's a question of what "the interface getting configured"
means, but I guess you could set up the transmitting interface?
Right, if the interface getting configured is the transmitted profile
the link_id is ignored.
@@ -5561,6 +5563,18 @@ static int nl80211_parse_mbssid_config(struct wiphy *wiphy,
}
config->tx_wdev = tx_netdev->ieee80211_ptr;
+
+ if (config->tx_wdev->valid_links) {
+ if (!tb[NL80211_MBSSID_CONFIG_ATTR_TX_LINK_ID])
+ return -ENOLINK;
+
+ config->tx_link_id =
+ nla_get_u8(tb[NL80211_MBSSID_CONFIG_ATTR_TX_LINK_ID]);
+
+ if (!(config->tx_wdev->valid_links &
+ BIT(config->tx_link_id)))
+ return -ENOLINK;
+ }
} else {
config->tx_wdev = dev->ieee80211_ptr;
}
So shouldn't that be one layer out, so the link ID can also apply if no
interface index was given, i.e. we took the else branch? Seems like that
should be applicable, or is there a specific reason not to apply in that
case?
The 'else' case in the highlighted snippet above is the same scenario as
the 'else' case you referred to, which is one layer out: "else if
(!config->index) {".
Both are executed when the interface getting configured is the
transmitting interface. The difference between these two 'else's is that
in one case userspace explicitly provides
"NL80211_MBSSID_CONFIG_ATTR_TX_IFINDEX" and in other it hasn't.
Similarly, for MLO, mac80211 does not need the link_id of the tx
interface because it already has the link_conf for it as part of basic
AP configuration parameters, hence link_id is ignored in both 'else's.
Thanks.
