From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 1/5] net: remove bogus RCU annotations on socket.wq
Date: Mon, 30 Jul 2018 09:44:54 +0200
Message-ID: <20180730074454.GA10461@lst.de>
References: <20180727140214.1938-1-hch@lst.de> <20180727140214.1938-2-hch@lst.de> <20180729.130551.870321755786430124.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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On Sun, Jul 29, 2018 at 01:05:51PM -0700, David Miller wrote:
> From: Christoph Hellwig <hch@lst.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@lst.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.

I disagree, but I'll resend it the patch with Eric and Paul in CC to
settle the argument.