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: Thu, 21 Aug 2008 05:27:54 -0700 (PDT)
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 21 Aug 2008 22:22:45 +1000

> On Thu, Aug 21, 2008 at 12:19:20PM +0000, Jarek Poplawski wrote:
> > 
> > Since qdisc_destroy() is used for destroying root qdisc too, isn't it
> > better to get this lock back in notify_and_destroy() like this:
> > 
> > if (old) {
> > 	if (parent)
> > 		sch_tree_lock()
> > 	qdisc_destroy()
> > 	if (parent)
> > 		sch_tree_unlock()
> > }
> 
> Ugly as it may look, I think this is probably the best fix for now.
> 
> For 2.6.28 we can fix it properly and remove this eyesore :)

This looks even worse, actually.

If we just unlinked this thing, we don't want anyone finding
it, even before we grab this lock, to adjust queue counts.