netdev - Re: Problem with bridge (mcast-to-ucast + hairpin) and Broadcom's 802.11f in their FullMAC fw

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Date:   Mon, 12 Mar 2018 22:49:51 +0100
From:   Rafał Miłecki <zajec5@...il.com>
To:     Linus Lüssing <linus.luessing@...3.blue>
Cc:     Felix Fietkau <nbd@....name>,
        Arend van Spriel <arend.vanspriel@...adcom.com>,
        Franky Lin <franky.lin@...adcom.com>,
        Hante Meuleman <hante.meuleman@...adcom.com>,
        Chi-Hsien Lin <chi-hsien.lin@...ress.com>,
        Wright Feng <wright.feng@...ress.com>,
        Pieter-Paul Giesberts <pieter-paul.giesberts@...adcom.com>,
        Network Development <netdev@...r.kernel.org>,
        bridge@...ts.linux-foundation.org,
        "linux-wireless@...r.kernel.org" <linux-wireless@...r.kernel.org>,
        "open list:BROADCOM BRCM80211 IEEE802.11n WIRELESS DRIVER" 
        <brcm80211-dev-list.pdl@...adcom.com>,
        "open list:BROADCOM BRCM80211 IEEE802.11n WIRELESS DRIVER
        <brcm80211-dev-list.pdl@...adcom.com>," 
        <brcm80211-dev-list@...ress.com>
Subject: Re: Problem with bridge (mcast-to-ucast + hairpin) and Broadcom's
 802.11f in their FullMAC fw

On 12 March 2018 at 12:08, Linus Lüssing <linus.luessing@...3.blue> wrote:
> On Tue, Feb 27, 2018 at 11:08:20AM +0100, Rafał Miłecki wrote:
>> I've problem when using OpenWrt/LEDE on a home router with Broadcom's
>> FullMAC WiFi chipset.
>
> Hi Rafał,
>
> Thanks for reporting this issue!
>
>> Can you see any solution for this problem? Is that an option to stop
>> multicast-to-unicast from touching 802.11f packets? Some other ideas?
>> Obviously I can't modify Broadcom's firmware and drop that obsoleted
>> standard.
>
> Just to avoid some potential confusion: This is more an issue of
> hairpinning than it is an issue of multicast-to-unicast per se,
> right?
>
> That is, if you set this to 0 manually:
> /sys/class/net/<ap-iface>/brport/multicast_to_unicast
> Then the issue still occurs, right?

I can't really tell, I didn't go into details on bridge +
mcast-to-unicast + hairpin.

By default OpenWrt/LEDE sets
/sys/class/net/<ap-iface>/brport/multicast_to_unicast
to 1. Changing it to 0 (with a simple echo) doesn't /fix/ the problem.

-- 
Rafał