[3.19.y-ckt stable] Patch "mac80211: Requeue work after scan complete for all VIF types." has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    mac80211: Requeue work after scan complete for all VIF types.

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt16.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 74d5b9bb6c3142631dcebd43c40574d7bb27375f Mon Sep 17 00:00:00 2001
From: Sachin Kulkarni <Sachin.Kulkarni at imgtec.com>
Date: Tue, 12 Jan 2016 14:30:19 +0530
Subject: mac80211: Requeue work after scan complete for all VIF types.

commit 4fa11ec726a32ea6dd768dbb2e2af3453a98ec0a upstream.

During a sw scan ieee80211_iface_work ignores work items for all vifs.
However after the scan complete work is requeued only for STA, ADHOC
and MESH iftypes.

This occasionally results in event processing getting delayed/not
processed for iftype AP when it coexists with a STA. This can result
in data halt and eventually disconnection on the AP interface.

Signed-off-by: Sachin Kulkarni <Sachin.Kulkarni at imgtec.com>
Signed-off-by: Johannes Berg <johannes.berg at intel.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/mac80211/ibss.c |  1 -
 net/mac80211/mesh.c | 11 -----------
 net/mac80211/mesh.h |  4 ----
 net/mac80211/mlme.c |  2 --
 net/mac80211/scan.c | 12 +++++++++++-
 5 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 53b419b..6e56d45 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -1621,7 +1621,6 @@ void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
 			continue;
 		sdata->u.ibss.last_scan_completed = jiffies;
-		ieee80211_queue_work(&local->hw, &sdata->work);
 	}
 	mutex_unlock(&local->iflist_mtx);
 }
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index eff8ac2..026ecf4 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -1298,17 +1298,6 @@ out:
 	sdata_unlock(sdata);
 }

-void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
-{
-	struct ieee80211_sub_if_data *sdata;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(sdata, &local->interfaces, list)
-		if (ieee80211_vif_is_mesh(&sdata->vif) &&
-		    ieee80211_sdata_running(sdata))
-			ieee80211_queue_work(&local->hw, &sdata->work);
-	rcu_read_unlock();
-}

 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
 {
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index 50c8473..472bdc7 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -358,14 +358,10 @@ static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
 }

-void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local);
-
 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
 void mesh_sync_adjust_tbtt(struct ieee80211_sub_if_data *sdata);
 void ieee80211s_stop(void);
 #else
-static inline void
-ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {}
 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
 { return false; }
 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 66acc4b..de4fa35 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -3914,8 +3914,6 @@ static void ieee80211_restart_sta_timer(struct ieee80211_sub_if_data *sdata)
 		if (!(flags & IEEE80211_HW_CONNECTION_MONITOR))
 			ieee80211_queue_work(&sdata->local->hw,
 					     &sdata->u.mgd.monitor_work);
-		/* and do all the other regular work too */
-		ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 	}
 }

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 34b4050..b39b488 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -310,6 +310,7 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 	bool was_scanning = local->scanning;
 	struct cfg80211_scan_request *scan_req;
 	struct ieee80211_sub_if_data *scan_sdata;
+	struct ieee80211_sub_if_data *sdata;

 	lockdep_assert_held(&local->mtx);

@@ -369,7 +370,16 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)

 	ieee80211_mlme_notify_scan_completed(local);
 	ieee80211_ibss_notify_scan_completed(local);
-	ieee80211_mesh_notify_scan_completed(local);
+
+	/* Requeue all the work that might have been ignored while
+	 * the scan was in progress; if there was none this will
+	 * just be a no-op for the particular interface.
+	 */
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (ieee80211_sdata_running(sdata))
+			ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+	}
+
 	if (was_scanning)
 		ieee80211_start_next_roc(local);
 }
--
2.7.0