From 666d695bbd0479e9853f9fb81a8202fcd6869ac8 Mon Sep 17 00:00:00 2001 From: Aditya Kumar Singh Date: Fri, 21 Jun 2024 11:04:39 +0530 Subject: [PATCH] nl80211: Fix simultaneous scanning failure in case of MLO Currently only one scan can be performed on per phy level at a time in the driver. Due to this, if another scan request is sent via anoother underlying phy, the kernel returns -EBUSY. This would result in hostapd trying to set the interface into station mode if it was originally in AP mode and retry sending a scan request. However, this behavior is expected in case of multi link operation and hence there is no need to switch the mode as such. Hence, add logic to not change the NL mode if the kernel returns -EBUSY during multi link AP operation. The caller can accordingly decide and, if needed, it can re-schedule a scan request after some time. Signed-off-by: Aditya Kumar Singh --- src/drivers/driver_nl80211_scan.c | 34 +++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/src/drivers/driver_nl80211_scan.c b/src/drivers/driver_nl80211_scan.c index 9a1e36f32..d0ed7ad95 100644 --- a/src/drivers/driver_nl80211_scan.c +++ b/src/drivers/driver_nl80211_scan.c @@ -416,6 +416,40 @@ int wpa_driver_nl80211_scan(struct i802_bss *bss, wpa_printf(MSG_DEBUG, "nl80211: Scan trigger failed: ret=%d " "(%s)", ret, strerror(-ret)); if (drv->hostapd && is_ap_interface(drv->nlmode)) { +#ifdef CONFIG_IEEE80211BE + /* For multi link BSS, retry scan if any other links + * are busy scanning. */ + if (ret == -EBUSY && + nl80211_link_valid(bss->valid_links, + params->link_id)) { + struct i802_bss *link_bss; + u8 link_id; + + wpa_printf(MSG_DEBUG, + "nl80211: Scan trigger on multi link BSS failed (requested link=%d on interface %s)", + params->link_id, bss->ifname); + + for (link_bss = drv->first_bss; link_bss; + link_bss = link_bss->next) { + if (link_bss->scan_link) + break; + } + + if (!link_bss) { + wpa_printf(MSG_DEBUG, + "nl80211: BSS information already running scan not available"); + goto fail; + } + + link_id = nl80211_get_link_id_from_link( + link_bss, link_bss->scan_link); + wpa_printf(MSG_DEBUG, + "nl80211: Scan already running on interface %s link %d", + link_bss->ifname, link_id); + goto fail; + } +#endif /* CONFIG_IEEE80211BE */ + /* * mac80211 does not allow scan requests in AP mode, so * try to do this in station mode.