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Date:   Tue, 28 Feb 2023 00:31:55 +0100
From:   Florian Westphal <fw@strlen.de>
To:     Alexander Atanasov <alexander.atanasov@virtuozzo.com>
Cc:     Florian Westphal <fw@strlen.de>, netdev@vger.kernel.org,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        Eric Dumazet <edumazet@google.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
Subject: Re: [PATCH] netfilter: nf_tables: always synchronize with readers
 before releasing tables
Message-ID: <20230227233155.GA6107@breakpoint.cc>
References: <20230227121720.3775652-1-alexander.atanasov@virtuozzo.com>
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 <20230227124402.GA30043@breakpoint.cc>
 <266de015-7712-8672-9ca0-67199817d587@virtuozzo.com>
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Alexander Atanasov <alexander.atanasov@virtuozzo.com> wrote:
> As i said i am still trying to figure out the basechain place,
> where is that synchronize_rcu() call done?

cleanup_net() in net/core/net_namespace.c.

pre_exit handlers run, then synchronize_rcu, then the
normal exit handlers, then exit_batch.

> > Do you see this with current kernels or did the splat happen with
> > an older version?
> 
> It's with a bit older kernel but there is no significant difference
> wrt nf_tables_api code.
> I will prepare a more detailed report for you.

Thanks.