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References: <20200707171515.110818-1-izabela.bakollari@gmail.com> <20200804160908.46193-1-izabela.bakollari@gmail.com>
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From:   Cong Wang <xiyou.wangcong@gmail.com>
Date:   Tue, 4 Aug 2020 14:28:28 -0700
Message-ID: <CAM_iQpV-AfX_=o0=ZhU2QzV_pmyWs8RKV0yyMuxFgwFAPwpnXw@mail.gmail.com>
Subject: Re: [PATCHv2 net-next] dropwatch: Support monitoring of dropped frames
To:     izabela.bakollari@gmail.com
Cc:     Neil Horman <nhorman@tuxdriver.com>,
        David Miller <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-kernel-mentees@lists.linuxfoundation.org
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On Tue, Aug 4, 2020 at 9:14 AM <izabela.bakollari@gmail.com> wrote:
>
> From: Izabela Bakollari <izabela.bakollari@gmail.com>
>
> Dropwatch is a utility that monitors dropped frames by having userspace
> record them over the dropwatch protocol over a file. This augument
> allows live monitoring of dropped frames using tools like tcpdump.
>
> With this feature, dropwatch allows two additional commands (start and
> stop interface) which allows the assignment of a net_device to the
> dropwatch protocol. When assinged, dropwatch will clone dropped frames,
> and receive them on the assigned interface, allowing tools like tcpdump
> to monitor for them.
>
> With this feature, create a dummy ethernet interface (ip link add dev
> dummy0 type dummy), assign it to the dropwatch kernel subsystem, by using
> these new commands, and then monitor dropped frames in real time by
> running tcpdump -i dummy0.

drop monitor is already able to send dropped packets to user-space,
and wireshark already catches up with this feature:

https://code.wireshark.org/review/gitweb?p=wireshark.git;a=commitdiff;h=a94a860c0644ec3b8a129fd243674a2e376ce1c8

So what you propose here seems pretty much a duplicate?

Thanks.