This is a note to let you know that I've just added the patch titled wifi: ath10k: Serialize wake_tx_queue ops to the 6.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-ath10k-serialize-wake_tx_queue-ops.patch and it can be found in the queue-6.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b719ebc37a1eacd4fd4f1264f731b016e5ec0c6e Mon Sep 17 00:00:00 2001 From: Alexander Wetzel <alexander@xxxxxxxxxxxxxx> Date: Thu, 23 Mar 2023 17:55:27 +0100 Subject: wifi: ath10k: Serialize wake_tx_queue ops From: Alexander Wetzel <alexander@xxxxxxxxxxxxxx> commit b719ebc37a1eacd4fd4f1264f731b016e5ec0c6e upstream. Serialize the ath10k implementation of the wake_tx_queue ops. ath10k_mac_op_wake_tx_queue() must not run concurrent since it's using ieee80211_txq_schedule_start(). The intend of this patch is to sort out an issue discovered in the discussion referred to by the Link tag. I can't test it with real hardware and thus just implemented the per-ac queue lock Felix suggested. One obvious alternative to the per-ac lock would be to bring back the txqs_lock commit bb2edb733586 ("ath10k: migrate to mac80211 txq scheduling") dropped. Fixes: bb2edb733586 ("ath10k: migrate to mac80211 txq scheduling") Reported-by: Felix Fietkau <nbd@xxxxxxxx> Link: https://lore.kernel.org/r/519b5bb9-8899-ae7c-4eff-f3116cdfdb56@xxxxxxxx CC: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Alexander Wetzel <alexander@xxxxxxxxxxxxxx> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20230323165527.156414-1-alexander@xxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/ath10k/core.c | 3 +++ drivers/net/wireless/ath/ath10k/core.h | 3 +++ drivers/net/wireless/ath/ath10k/mac.c | 6 ++++-- 3 files changed, 10 insertions(+), 2 deletions(-) --- a/drivers/net/wireless/ath/ath10k/core.c +++ b/drivers/net/wireless/ath/ath10k/core.c @@ -3634,6 +3634,9 @@ struct ath10k *ath10k_core_create(size_t mutex_init(&ar->dump_mutex); spin_lock_init(&ar->data_lock); + for (int ac = 0; ac < IEEE80211_NUM_ACS; ac++) + spin_lock_init(&ar->queue_lock[ac]); + INIT_LIST_HEAD(&ar->peers); init_waitqueue_head(&ar->peer_mapping_wq); init_waitqueue_head(&ar->htt.empty_tx_wq); --- a/drivers/net/wireless/ath/ath10k/core.h +++ b/drivers/net/wireless/ath/ath10k/core.h @@ -1170,6 +1170,9 @@ struct ath10k { /* protects shared structure data */ spinlock_t data_lock; + /* serialize wake_tx_queue calls per ac */ + spinlock_t queue_lock[IEEE80211_NUM_ACS]; + struct list_head arvifs; struct list_head peers; struct ath10k_peer *peer_map[ATH10K_MAX_NUM_PEER_IDS]; --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -4732,13 +4732,14 @@ static void ath10k_mac_op_wake_tx_queue( { struct ath10k *ar = hw->priv; int ret; - u8 ac; + u8 ac = txq->ac; ath10k_htt_tx_txq_update(hw, txq); if (ar->htt.tx_q_state.mode != HTT_TX_MODE_SWITCH_PUSH) return; - ac = txq->ac; + spin_lock_bh(&ar->queue_lock[ac]); + ieee80211_txq_schedule_start(hw, ac); txq = ieee80211_next_txq(hw, ac); if (!txq) @@ -4753,6 +4754,7 @@ static void ath10k_mac_op_wake_tx_queue( ath10k_htt_tx_txq_update(hw, txq); out: ieee80211_txq_schedule_end(hw, ac); + spin_unlock_bh(&ar->queue_lock[ac]); } /* Must not be called with conf_mutex held as workers can use that also. */ Patches currently in stable-queue which might be from alexander@xxxxxxxxxxxxxx are queue-6.4/wifi-ath10k-serialize-wake_tx_queue-ops.patch