From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH net-next] net, cls: allow for deleting all filters for
 given parent
Date: Mon, 06 Jun 2016 21:25:46 +0200
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References: <cd8455dfef0cccec5ef0a1ca2d1f678e9397d66e.1465056745.git.daniel@iogearbox.net> <CAM_iQpWDc1JAa9MhcSAOdJVVRoG52Z+p47CD-rd81LzN28zk1A@mail.gmail.com>
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Cc: David Miller <davem@davemloft.net>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	john fastabend <john.fastabend@gmail.com>,
	Jamal Hadi Salim <jhs@mojatatu.com>,
	Linux Kernel Network Developers <netdev@vger.kernel.org>
To: Cong Wang <xiyou.wangcong@gmail.com>
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On 06/06/2016 07:12 PM, Cong Wang wrote:
> On Sat, Jun 4, 2016 at 9:24 AM, Daniel Borkmann <daniel@iogearbox.net> wrote:
>> +       if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
>> +               tcf_destroy_chain(chain);
>> +               err = 0;
>> +               goto errout;
>> +       }
>
> We need to notify users we removed which filters, right?

As far as I know, most such use cases that listen on this are bypasses
that mirror kernel configs from user space ... but well, sure, I can add
a notification if people care. Would do this as a separate patch.

Looking into this, I would probably make this a single notification that
denotes this 'wild-card' removal for that parent instead of calling
tfilter_notify() for each filter separately (which allocs skb, dumps it,
etc), qdisc del doesn't loop through it either, so probably fine this way.

Thanks,
Daniel