This is a note to let you know that I've just added the patch titled ath10k: Fix tx hanging to the 5.15-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: ath10k-fix-tx-hanging.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e518a0c2d80459a37dad519f40b1345f06e13b34 Author: Sebastian Gottschall <s.gottschall@xxxxxxxxxx> Date: Wed May 5 15:58:06 2021 +0700 ath10k: Fix tx hanging [ Upstream commit e8a91863eba3966a447d2daa1526082d52b5db2a ] While running stress tests in roaming scenarios (switching ap's every 5 seconds, we discovered a issue which leads to tx hangings of exactly 5 seconds while or after scanning for new accesspoints. We found out that this hanging is triggered by ath10k_mac_wait_tx_complete since the empty_tx_wq was not wake when the num_tx_pending counter reaches zero. To fix this, we simply move the wake_up call to htt_tx_dec_pending, since this call was missed on several locations within the ath10k code. Signed-off-by: Sebastian Gottschall <s.gottschall@xxxxxxxxxx> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20210505085806.11474-1-s.gottschall@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/wireless/ath/ath10k/htt_tx.c b/drivers/net/wireless/ath/ath10k/htt_tx.c index d6b8bdcef4160..b793eac2cfac8 100644 --- a/drivers/net/wireless/ath/ath10k/htt_tx.c +++ b/drivers/net/wireless/ath/ath10k/htt_tx.c @@ -147,6 +147,9 @@ void ath10k_htt_tx_dec_pending(struct ath10k_htt *htt) htt->num_pending_tx--; if (htt->num_pending_tx == htt->max_num_pending_tx - 1) ath10k_mac_tx_unlock(htt->ar, ATH10K_TX_PAUSE_Q_FULL); + + if (htt->num_pending_tx == 0) + wake_up(&htt->empty_tx_wq); } int ath10k_htt_tx_inc_pending(struct ath10k_htt *htt) diff --git a/drivers/net/wireless/ath/ath10k/txrx.c b/drivers/net/wireless/ath/ath10k/txrx.c index 7c9ea0c073d8b..6f8b642188941 100644 --- a/drivers/net/wireless/ath/ath10k/txrx.c +++ b/drivers/net/wireless/ath/ath10k/txrx.c @@ -82,8 +82,6 @@ int ath10k_txrx_tx_unref(struct ath10k_htt *htt, flags = skb_cb->flags; ath10k_htt_tx_free_msdu_id(htt, tx_done->msdu_id); ath10k_htt_tx_dec_pending(htt); - if (htt->num_pending_tx == 0) - wake_up(&htt->empty_tx_wq); spin_unlock_bh(&htt->tx_lock); rcu_read_lock();