[NETPOLL]: fix initialization/NAPI race
This fixes a race during initialization with the NAPI softirq
processing by using an RCU approach.
This race was discovered when refill_skbs() was added to
the setup code.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index c02a08d..996787b 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -732,6 +732,9 @@
/* last thing to do is link it to the net device structure */
ndev->npinfo = npinfo;
+ /* avoid racing with NAPI reading npinfo */
+ synchronize_rcu();
+
return 0;
release:
