From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira Ayuso <pablo@netfilter.org>
Subject: Re: [PATCH 3/6] netfilter: ctnetlink: use GFP_ATOMIC in all
 allocations
Date: Tue, 6 Mar 2012 16:35:13 +0100
Message-ID: <20120306153513.GA1725@1984>
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Cc: netfilter-devel@vger.kernel.org, davem@davemloft.net,
	netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Tue, Mar 06, 2012 at 07:09:17AM -0800, Eric Dumazet wrote:
> Le mardi 06 mars 2012 =E0 15:48 +0100, Pablo Neira Ayuso a =E9crit :
> > On Tue, Mar 06, 2012 at 04:50:21AM -0800, Eric Dumazet wrote:
>=20
> > > This cant be right.
> > >=20
> > > Really this must be kept as GFP_KERNEL allocations.
> > >=20
> > > Only if .call_rcu member is used in place of .call rcu_read_lock(=
) is
> > > held instead of nfnl_lock().
> >=20
> > I thought we couldn't sleep while holding rcu_read_lock.
>=20
> True, but as far as I can see we dont hold rcu_read_lock() at this
> point, only a mutex.
>=20
> I added the .call_rcu() mechanism in struct nfnl_callback only for ve=
ry
> specific needs, namely performance improvements in commit 84a797dd0
> (netfilter: nfnetlink_queue: provide rcu enabled callbacks)

Sorry, I overlooked that changed, I still thought that we were calling
these under rcu_read_lock.

This patch has to be kept out indeed. Thanks for spotting this Eric.