net: reintroduce missing rcu_assign_pointer() calls

commit a9b3cd7f32 (rcu: convert uses of rcu_assign_pointer(x, NULL) to
RCU_INIT_POINTER) did a lot of incorrect changes, since it did a
complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x,
y).

We miss needed barriers, even on x86, when y is not NULL.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index c879c1a..b4f8d84 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -59,7 +59,7 @@
 		nfnl_unlock();
 		return -EBUSY;
 	}
-	RCU_INIT_POINTER(subsys_table[n->subsys_id], n);
+	rcu_assign_pointer(subsys_table[n->subsys_id], n);
 	nfnl_unlock();
 
 	return 0;
@@ -210,7 +210,7 @@
 	if (!nfnl)
 		return -ENOMEM;
 	net->nfnl_stash = nfnl;
-	RCU_INIT_POINTER(net->nfnl, nfnl);
+	rcu_assign_pointer(net->nfnl, nfnl);
 	return 0;
 }