We currently force a synchronize_net() in netdev_set_master()

This seems necessary only when a slave had a master and we dismantle it.

In the other case ("ifenslave bond0 ethO"), we dont need this long
delay.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
---
diff --git a/net/core/dev.c b/net/core/dev.c
index 17b1686..ff578ff 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3733,11 +3733,10 @@ int netdev_set_master(struct net_device *slave, struct net_device *master)
 
 	slave->master = master;
 
-	synchronize_net();
-
-	if (old)
+	if (old) {
+		synchronize_net();
 		dev_put(old);
-
+	}
 	if (master)
 		slave->flags |= IFF_SLAVE;
 	else


--

[ message continues ]

From: Eric Dumazet <eric.dumazet@gmail.com>

Depends upon the net-2.6 race fix?

Thanks for telling me :-/
--

[ message continues ]

I believe it's not related. It's net-next-2.6 material, for sure :)

But yes, I discovered the race fix while studying netdev_set_master()

Thanks David


--

[ message continues ]

From: Eric Dumazet <eric.dumazet@gmail.com>

It was not an issue of related, but rather "B won't apply cleanly
without A". Even line offsets can make "git apply" reject.
--

[ message continues ]

I see, I can resubmit later if you prefer, once net-2.6 fix is pulled in
net-next, there is no hurry :)



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[ message continues ]

From: Eric Dumazet <eric.dumazet@gmail.com>

No need, just let me know about this stuff in the future, that's
all :-)
--

[ message continues ]

From: Eric Dumazet <eric.dumazet@gmail.com>

Applied.
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[ message continues ]