This is a note to let you know that I've just added the patch titled wcn36xx: Fix (QoS) null data frame bitrate/modulation 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: wcn36xx-fix-qos-null-data-frame-bitrate-modulation.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. >From d3fd2c95c1c13ec217d43ebef3c61cfa00a6cd37 Mon Sep 17 00:00:00 2001 From: Loic Poulain <loic.poulain@xxxxxxxxxx> Date: Mon, 25 Oct 2021 16:12:18 +0300 Subject: wcn36xx: Fix (QoS) null data frame bitrate/modulation From: Loic Poulain <loic.poulain@xxxxxxxxxx> commit d3fd2c95c1c13ec217d43ebef3c61cfa00a6cd37 upstream. We observe unexpected connection drops with some APs due to non-acked mac80211 generated null data frames (keep-alive). After debugging and capture, we noticed that null frames are submitted at standard data bitrate and that the given APs are in trouble with that. After setting the null frame bitrate to control bitrate, all null frames are acked as expected and connection is maintained. Not sure if it's a requirement of the specification, but it seems the right thing to do anyway, null frames are mostly used for control purpose (power-saving, keep-alive...), and submitting them with a slower/simpler bitrate/modulation is more robust. Cc: stable@xxxxxxxxxxxxxxx Fixes: 512b191d9652 ("wcn36xx: Fix TX data path") Signed-off-by: Loic Poulain <loic.poulain@xxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1634560399-15290-1-git-send-email-loic.poulain@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/wcn36xx/txrx.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/wireless/ath/wcn36xx/txrx.c +++ b/drivers/net/wireless/ath/wcn36xx/txrx.c @@ -429,6 +429,7 @@ static void wcn36xx_set_tx_data(struct w if (ieee80211_is_any_nullfunc(hdr->frame_control)) { /* Don't use a regular queue for null packet (no ampdu) */ bd->queue_id = WCN36XX_TX_U_WQ_ID; + bd->bd_rate = WCN36XX_BD_RATE_CTRL; } if (bcast) { Patches currently in stable-queue which might be from loic.poulain@xxxxxxxxxx are queue-5.15/wcn36xx-fix-ht40-capability-for-2ghz-band.patch queue-5.15/wcn36xx-handle-connection-loss-indication.patch queue-5.15/wcn36xx-fix-tx_status-mechanism.patch queue-5.15/wcn36xx-fix-qos-null-data-frame-bitrate-modulation.patch