net/802/mrp: fix lockdep splat

edumazet · davem330 · commit faff57a92ba1 · 2013-05-14T13:02:30.000-07:00
commit fb745e9 ("net/802/mrp: fix possible race condition when calling mrp_pdu_queue()") introduced a lockdep splat. [ 19.735147] ================================= [ 19.735235] [ INFO: inconsistent lock state ] [ 19.735324] 3.9.2-build-0063 #4 Not tainted [ 19.735412] --------------------------------- [ 19.735500] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 19.735592] rmmod/1840 [HC0[0]:SC0[0]:HE1:SE1] takes: [ 19.735682] (&(&app->lock)->rlock#2){+.?...}, at: [<f862bb5b>] mrp_uninit_applicant+0x69/0xba [mrp] app->lock is normally taken under softirq context, so disable BH to avoid the splat. Reported-by: Denys Fedoryshchenko <denys@visp.net.lb> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Ward <david.ward@ll.mit.edu> Cc: Cong Wang <amwang@redhat.com> Tested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/802/mrp.c b/net/802/mrp.c
@@ -871,10 +871,10 @@ void mrp_uninit_applicant(struct net_device *dev, struct mrp_application *appl)
 	 */
 	del_timer_sync(&app->join_timer);
 
-	spin_lock(&app->lock);
+	spin_lock_bh(&app->lock);
 	mrp_mad_event(app, MRP_EVENT_TX);
 	mrp_pdu_queue(app);
-	spin_unlock(&app->lock);
+	spin_unlock_bh(&app->lock);
 
 	mrp_queue_xmit(app);
 
