From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] netfilter: use per-cpu recursive lock (v11)
Date: Tue, 21 Apr 2009 01:49:23 -0700 (PDT)
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From: Lai Jiangshan <laijs@cn.fujitsu.com>
Date: Tue, 21 Apr 2009 16:42:40 +0800

> softirq is always not nesting. Why we need recursive lock?

Netfilter itself, is nesting.

When using bridging netfilter, iptables can be entered twice
in the same call chain.