netdev - Re: [PATCH 1/5] net: remove bogus RCU annotations on socket.wq

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Message-Id: <20180729.130551.870321755786430124.davem@davemloft.net>
Date:   Sun, 29 Jul 2018 13:05:51 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     hch@....de
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH 1/5] net: remove bogus RCU annotations on socket.wq

From: Christoph Hellwig <hch@....de>
Date: Fri, 27 Jul 2018 16:02:10 +0200

> We never use RCU protection for it, just a lot of cargo-cult
> rcu_deference_protects calls.
> 
> Note that we do keep the kfree_rcu call for it, as the references through
> struct sock are RCU protected and thus might require a grace period before
> freeing.
> 
> Signed-off-by: Christoph Hellwig <hch@....de>

These were added by Eric Dumazet and I would never accuse him of cargo
cult programming.

All of the rcu_dereference_protects() calls are legit, even though some
of them use '1' as the protects condition because in fact we know the
object is dead and gone through an RCU cycle at that point.

Let's skip this for now.  The rest of your series looks fine so why
don't you resubmit this series with just #2-#5?

Thanks.