From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: [Patch net-next] act_mirred: use tcfm_dev in tcf_mirred_get_dev()
Date: Sat, 2 Dec 2017 07:56:34 +0100
Message-ID: <20171202065634.GA1821@nanopsycho>
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 <20171201175619.GC2396@nanopsycho>
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Jiri Pirko <jiri@mellanox.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>
To: Cong Wang <xiyou.wangcong@gmail.com>
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Fri, Dec 01, 2017 at 10:46:42PM CET, xiyou.wangcong@gmail.com wrote:
>On Fri, Dec 1, 2017 at 9:56 AM, Jiri Pirko <jiri@resnulli.us> wrote:
>>
>> Isn't this here so user may specify a ifindex of netdev which is not yet
>> present on the system (not sure how much sense that would make though...)
>
>How is this even possible? If an ifindex is not present, we return ENODEV:

Right, I missed this. Thanks.

>
>        if (parm->ifindex) {
>                dev = __dev_get_by_index(net, parm->ifindex);
>                if (dev == NULL) {
>                        if (exists)
>                                tcf_idr_release(*a, bind);
>                        return -ENODEV;
>                }