This is a note to let you know that I've just added the patch titled

ath10k: fix fetching channel during potential radar detection

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: ath10k-fix-fetching-channel-during-potential-radar-detection.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Sun Mar 18 16:55:33 CET 2018

From: Mohammed Shafi Shajakhan mohammed@qti.qualcomm.com Date: Wed, 8 Mar 2017 18:03:32 +0530 Subject: ath10k: fix fetching channel during potential radar detection

From: Mohammed Shafi Shajakhan mohammed@qti.qualcomm.com

[ Upstream commit a28f6f27a88f047f03f04b9246ca260ebc91455e ]

Fetch target operating channel during potential radar detection when the interface is just brought up, but no channel is assigned from userspace. In this scenario rx_channel may not be having a valid pointer hence fetch the target operating channel to avoid warnings as below which can be triggered by the commands with DFS testing over longer run

comamnds: iw wlan1 set type mesh ifconfig wlan1 up (valid tgt_oper_chan only) iw wlan1 cac trigger freq 5260 HT20 (valid rx_channel, tgt_oper_chan) iw wlan1 cac trigger freq 5280 HT20 iw wlan1 cac trigger freq 5300 HT20

Once the CAC expires, current channel context will be removed and we are only left with the fallback option of using 'target operating channel'

Firmware and driver log: ath: phy1: DFS: radar found on freq=5300: id=1, pri=1125, count=5, count_false=4 ath: phy1: DFS: radar found on freq=5260: id=5, pri=3151, count=6, count_false=11 ath: phy1: DFS: radar found on freq=5280: id=1, pri=1351, count=6, count_false=4 ath: phy1: DFS: radar found on freq=5300: id=1, pri=1125, count=5, count_false=4 ath10k_pci 0001:01:00.0: failed to derive channel for radar pulse, treating as radar ath10k_pci 0001:01:00.0: failed to derive channel for radar pulse, treating as radar

Call trace:

WARNING: CPU: 1 PID: 2145 at backports-20161201-3.14.77-9ab3068/net/wireless/chan.c:265 cfg80211_set_dfs_state+0x3c/0x88 [cfg80211]()

Workqueue: phy1 ieee80211_dfs_radar_detected_work [mac80211] [<c0320770>] (warn_slowpath_null) from [<bf79b90c>] (cfg80211_set_dfs_state+0x3c/0x88 [cfg80211]) [<bf79b90c>] (cfg80211_set_dfs_state [cfg80211]) from [<bf79697c>] (cfg80211_radar_event+0xc4/0x140 [cfg80211]) [<bf79697c>] (cfg80211_radar_event [cfg80211]) from [<bf83c058>] (ieee80211_dfs_radar_detected_work+0xa8/0xb4 [mac80211]) [<bf83c058>] (ieee80211_dfs_radar_detected_work [mac80211]) from [<c0339518>] (process_one_work+0x298/0x4a4)

Signed-off-by: Mohammed Shafi Shajakhan mohammed@qti.qualcomm.com Signed-off-by: Kalle Valo kvalo@qca.qualcomm.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/ath/ath10k/wmi.c | 5 +++++ 1 file changed, 5 insertions(+)

--- a/drivers/net/wireless/ath/ath10k/wmi.c +++ b/drivers/net/wireless/ath/ath10k/wmi.c @@ -3638,6 +3638,11 @@ static void ath10k_dfs_radar_report(stru

spin_lock_bh(&ar->data_lock); ch = ar->rx_channel; + + /* fetch target operating channel during channel change */ + if (!ch) + ch = ar->tgt_oper_chan; + spin_unlock_bh(&ar->data_lock);

if (!ch) {

Patches currently in stable-queue which might be from mohammed@qti.qualcomm.com are

queue-4.9/ath10k-fix-fetching-channel-during-potential-radar-detection.patch queue-4.9/ath10k-fix-compile-time-sanity-check-for-ce4-buffer-size.patch queue-4.9/ath10k-fix-a-warning-during-channel-switch-with-multiple-vaps.patch queue-4.9/ath10k-disallow-dfs-simulation-if-dfs-channel-is-not-enabled.patch