Patch "ath10k: disallow DFS simulation if DFS channel is not enabled" has been added to the 4.4-stable tree

Patch "ath10k: disallow DFS simulation if DFS channel is not enabled" has been added to the 4.4-stable tree

[gregkh]

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

    ath10k: disallow DFS simulation if DFS channel is not enabled

to the 4.4-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:
     ath10k-disallow-dfs-simulation-if-dfs-channel-is-not-enabled.patch
and it can be found in the queue-4.4 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 Mon Mar 19 09:58:12 CET 2018
From: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Date: Wed, 22 Feb 2017 21:03:11 +0530
Subject: ath10k: disallow DFS simulation if DFS channel is not enabled

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


[ Upstream commit ca07baab0b1e627ae1d4a55d190fb1c9d32a3445 ]

If DFS is not enabled in hostapd (ieee80211h=0) DFS channels shall
not be available for use even though the hardware may have the capability
to support DFS. With this configuration (DFS disabled in hostapd) trying to
bring up ath10k device in DFS channel for AP mode fails and trying to
simulate DFS in ath10k debugfs results in a warning in cfg80211 complaining
invalid channel and this should be avoided in the driver itself rather than
false propogating RADAR detection to mac80211/cfg80211. Fix this by
checking for the first vif 'is_started' state(should work for client mode
as well) as all the vifs shall be configured for the same channel

sys/kernel/debug/ieee80211/phy1/ath10k# echo 1 > dfs_simulate_radar

WARNING: at net/wireless/chan.c:265 cfg80211_radar_event+0x24/0x60
Workqueue: phy0 ieee80211_dfs_radar_detected_work [mac80211]
[<c022f2d4>] (warn_slowpath_null) from
[<bf72dab8>] (cfg80211_radar_event+0x24/0x60 [cfg80211])
[<bf72dab8>] (cfg80211_radar_event [cfg80211]) from
[<bf7813e0>] (ieee80211_dfs_radar_detected_work+0x94/0xa0 [mac80211])
[<bf7813e0>] (ieee80211_dfs_radar_detected_work [mac80211]) from
[<c0242320>] (process_one_work+0x20c/0x32c)

WARNING: at net/wireless/nl80211.c:2488 nl80211_get_mpath+0x13c/0x4cc
 Workqueue: phy0 ieee80211_dfs_radar_detected_work [mac80211]
[<c022f2d4>] (warn_slowpath_null) from
[<bf72dab8>] (cfg80211_radar_event+0x24/0x60 [cfg80211])
[<bf72dab8>] (cfg80211_radar_event [cfg80211]) from
[<bf7813e0>] (ieee80211_dfs_radar_detected_work+0x94/0xa0 [mac80211])
[<bf7813e0>] (ieee80211_dfs_radar_detected_work [mac80211]) from
[<c0242320>] (process_one_work+0x20c/0x32c)

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/debug.c |    9 +++++++++
 1 file changed, 9 insertions(+)

--- a/drivers/net/wireless/ath/ath10k/debug.c
+++ b/drivers/net/wireless/ath/ath10k/debug.c
@@ -1892,6 +1892,15 @@ static ssize_t ath10k_write_simulate_rad
 					   size_t count, loff_t *ppos)
 {
 	struct ath10k *ar = file->private_data;
+	struct ath10k_vif *arvif;
+
+	/* Just check for for the first vif alone, as all the vifs will be
+	 * sharing the same channel and if the channel is disabled, all the
+	 * vifs will share the same 'is_started' state.
+	 */
+	arvif = list_first_entry(&ar->arvifs, typeof(*arvif), list);
+	if (!arvif->is_started)
+		return -EINVAL;
 
 	ieee80211_radar_detected(ar->hw);
 


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

queue-4.4/ath10k-fix-a-warning-during-channel-switch-with-multiple-vaps.patch
queue-4.4/ath10k-disallow-dfs-simulation-if-dfs-channel-is-not-enabled.patch