From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] pkt_sched: Destroy gen estimators under rtnl_lock().
Date: Mon, 11 Aug 2008 18:12:35 -0700 (PDT)
Message-ID: <20080811.181235.141399855.davem@davemloft.net>
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From: Jarek Poplawski <jarkao2@gmail.com>
Date: Mon, 11 Aug 2008 22:53:57 +0200

> pkt_sched: Destroy gen estimators under rtnl_lock().
> 
> gen_kill_estimator() requires rtnl_lock() protection, and since it is
> called in qdisc ->destroy() too, this has to go back from RCU callback
> to qdisc_destroy().
> 
> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>

We can't do this.  And at a minimum, the final ->reset() must
occur in the RCU callback, otherwise asynchronous threads of
execution could queue packets into this dying qdisc and
such packets would leak forever.