Patch "mac80211_hwsim: enforce PS_MANUAL_POLL to be set after PS_ENABLED" has been added to the 4.9-stable tree

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

mac80211_hwsim: enforce PS_MANUAL_POLL to be set after PS_ENABLED

to the 4.9-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:
mac80211_hwsim-enforce-ps_manual_poll-to-be-set-after-ps_enabled.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 <[email protected]> know about it.

From: Adiel Aloni <[email protected]>
Date: Fri, 1 Dec 2017 13:50:53 +0200
Subject: mac80211_hwsim: enforce PS_MANUAL_POLL to be set after PS_ENABLED

From: Adiel Aloni <[email protected]>

[ Upstream commit e16ea4bb516bc21ea2202f2107718b29218bea59 ]

Enforce using PS_MANUAL_POLL in ps hwsim debugfs to trigger a poll, only if PS_ENABLED was set before.
This is required due to commit c9491367b759 ("mac80211: always update the PM state of a peer on MGMT / DATA frames") that enforces the ap to check only mgmt/data frames ps bit, and then update station's power save accordingly.
When sending only ps-poll (control frame) the ap will not be aware that the station entered power save.
Setting ps enable before triggering ps_poll, will send NDP with PM bit enabled first.

---
 drivers/net/wireless/mac80211_hwsim.c |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

@@ -728,16 +728,21 @@ static int hwsim_fops_ps_write(void *dat
 	    val != PS_MANUAL_POLL)
 		return -EINVAL;
 
-	old_ps = data->ps;
-	data->ps = val;
-
-	local_bh_disable();
 	if (val == PS_MANUAL_POLL) {
+		if (data->ps != PS_ENABLED)
+			return -EINVAL;
+		local_bh_disable();
 		ieee80211_iterate_active_interfaces_atomic(
 			data->hw, IEEE80211_IFACE_ITER_NORMAL,
 			hwsim_send_ps_poll, data);
-		data->ps_poll_pending = true;
-	} else if (old_ps == PS_DISABLED && val != PS_DISABLED) {
+		local_bh_enable();
+		return 0;
+	}
+	old_ps = data->ps;
+	data->ps = val;
+
+	local_bh_disable();
+	if (old_ps == PS_DISABLED && val != PS_DISABLED) {
 		ieee80211_iterate_active_interfaces_atomic(
 			data->hw, IEEE80211_IFACE_ITER_NORMAL,
 			hwsim_send_nullfunc_ps, data);

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/mac80211_hwsim-enforce-ps_manual_poll-to-be-set-after-ps_enabled.patch