macvtap: rcu_dereference outside read-lock section

rcu_dereference occurs in update section. Replacement by rcu_dereference_protected in order to prevent lockdep complaint. Found by Linux Driver Verification project (linuxtesting.org) Signed-off-by: Denis Efremov <[email protected]> Acked-by: Michael S. Tsirkin <[email protected]> Signed-off-by: David S. Miller <[email protected]>
chewitt · Aug 12, 2012 · 3a7f8c3 · 3a7f8c3
1 parent 2359a47
commit 3a7f8c3
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
@@ -94,7 +94,8 @@ static int get_slot(struct macvlan_dev *vlan, struct macvtap_queue *q)
 	int i;
 
 	for (i = 0; i < MAX_MACVTAP_QUEUES; i++) {
-		if (rcu_dereference(vlan->taps[i]) == q)
+		if (rcu_dereference_protected(vlan->taps[i],
+					      lockdep_is_held(&macvtap_lock)) == q)
 			return i;
 	}