Date: Thu, 14 Apr 2016 18:08:14 +0200 (CEST)
From: Jiri Kosina <jikos@kernel.org>
To: Phil Sutter <phil@nwl.cc>
cc: Eric Dumazet <eric.dumazet@gmail.com>, Jamal Hadi Salim <jhs@mojatatu.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Deleting child qdisc doesn't reset parent to default qdisc?
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On Thu, 14 Apr 2016, Phil Sutter wrote:

> > > I've came across the behavior where adding a child qdisc and then deleting 
> > > it again makes the networking dysfunctional (I guess that's because all of 
> > > a sudden there is absolutely no working qdisc on the device, although 
> > > there originally was a default one in the parent).
> > > 
> > > In a nutshell, is this expected behavior or bug?
> > 
> > This is the expected behavior.
> 
> OTOH some qdiscs (CBQ, DRR, DSMARK, HFSC, HTB, QFQ) assign the default
> one upon deletion instead of noop_qdisc, hence I would describe
> the situation using the words 'inconsistent' and 'accident' rather than
> 'expected'. :)

Would a patch that'd unify this in a sense that all qdiscs would assign 
the default one upon deletion acceptable?

Thanks,

-- 
Jiri Kosina
SUSE Labs