netdev - Re: Question on IGMP snooping on switch managment port

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Date: Tue, 18 Jul 2023 12:43:17 +0200
From: Riccardo Laiolo <laiolo@...ff.it>
To: Andrew Lunn <andrew@...n.ch>
Cc: netdev@...r.kernel.org
Subject: Re: Question on IGMP snooping on switch managment port

> I think when the MV88E6XXX_PORT_CTL0_IGMP_MLD_SNOOP bit is reset the 
> switch is not
> parsing the payload looking for the IGMP header, which is fine. But 
> when the system
> tries to answer to the querier its packet get trapped in his own port 
> rule since the
> Membership Report destination address is the multicast group address.

Hi,

Upon further investigations, I found that IGMP Membership Reports coming from my device are
received by other neighboring hosts but don't get forwarded to the router port.
This appears to confirm my quoted statement.

Can you please explain why MV88E6XXX_PORT_CTL0_IGMP_MLD_SNOOP should be reset
on the CPU port? Shouldn't IGMP packets be managed the same way on every physical port?

Thanks for the support

-- 
Riccardo Laiolo