From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Lunn <andrew@lunn.ch>
Subject: Re: question about function igmp_stop_timer() in net/ipv4/igmp.c
Date: Tue, 25 Oct 2016 14:19:36 +0200
Message-ID: <20161025121936.GI22417@lunn.ch>
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To: Dongpo Li <lidongpo@hisilicon.com>
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> Otherwise the host can't send IGMP leave message when it leaves the
> group because the im->reporter is 0.

Leave is optional for IGMP v2, so net sending it is fine. And only a
querier is going to take any notice of it.

What happens when you have a querier in your network and you are using
IGMPv3. That is the use case which matters.

     Andrew