cfg80211: process events caused by suspend before suspending

When suspending without WoWLAN, cfg80211 will ask drivers to
disconnect. Even when the driver does this synchronously, and
immediately returns with a notification, cfg80211 schedules
the handling thereof to a workqueue, and may then call back
into the driver when the driver was already suspended/ing.

Fix this by processing all events caused by cfg80211_leave_all()
directly after that function returns. The driver still needs to
do the right thing here and wait for the firmware response, but
that is - at least - true for mwifiex where this occurred.

Reported-by: Amitkumar Karwar <akarwar@marvell.com>
Tested-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/sysfs.c

@@ -104,13 +104,16 @@ static int wiphy_suspend(struct device *dev)
 
 	rtnl_lock();
 	if (rdev->wiphy.registered) {
-		if (!rdev->wiphy.wowlan_config)
+		if (!rdev->wiphy.wowlan_config) {
 			cfg80211_leave_all(rdev);
+			cfg80211_process_rdev_events(rdev);
+		}
 		if (rdev->ops->suspend)
 			ret = rdev_suspend(rdev, rdev->wiphy.wowlan_config);
 		if (ret == 1) {
 			/* Driver refuse to configure wowlan */
 			cfg80211_leave_all(rdev);
+			cfg80211_process_rdev_events(rdev);
 			ret = rdev_suspend(rdev, NULL);
 		}
 	}