mac80211: use synchronize_rcu() with rcu_barrier()
The RCU docs used to state that rcu_barrier() included a wait
for an RCU grace period; however the comments for rcu_barrier()
as of commit f0a0e6f... "rcu: Clarify memory-ordering properties
of grace-period primitives" contradict this.
So add back synchronize_{rcu,net}() to where they once were,
but keep the rcu_barrier()s for the call_rcu() callbacks.
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Bob Copeland <bob@cozybit.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 490990e..1a89c80 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1043,6 +1043,7 @@
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
sta_info_flush_defer(vlan);
sta_info_flush_defer(sdata);
+ synchronize_net();
rcu_barrier();
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
sta_info_flush_cleanup(vlan);