Wen Gong <quic_wgong@xxxxxxxxxxx> wrote: > Deadlock is easily happened while shutdown wlan interface such as run > "ifconfig wlan0 down". > > The reason is because when ar->regd_update_work is ran, it will > call wiphy_lock(ar->hw->wiphy) in function ath12k_regd_update() which > is running in workqueue of ieee80211_local queued by ieee80211_queue_work(). > Another thread from "ifconfig wlan0 down" will also accuqire the lock > by wiphy_lock(sdata->local->hw.wiphy) in function ieee80211_stop(), and > then it call ieee80211_stop_device() to flush_workqueue(local->workqueue), > this will wait the workqueue of ieee80211_local finished. Then deadlock > will happen easily if the two thread run meanwhile. > > Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4 > > Signed-off-by: Wen Gong <quic_wgong@xxxxxxxxxxx> > Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> Patch applied to ath-next branch of ath.git, thanks. 8198950ccb7d wifi: ath12k: avoid deadlock by change ieee80211_queue_work for regd_update_work -- https://patchwork.kernel.org/project/linux-wireless/patch/20230718024724.29120-1-quic_wgong@xxxxxxxxxxx/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
