Re: [PATCH v3 RFC 3/4] net: dsa: hsr: Enable in KSZ9477 switch HW HSR offloading

Vladimir Oltean
2023-09-05T16:33:26Z

On Tue, Sep 05, 2023 at 04:03:55PM +0300, Vladimir Oltean wrote:
> > > What are the causes due to which self-address filtering and duplicate
> > > elimination only work "most of the time"?
> >
> > Please refer to section "KSZ9477 CHIP LIMITATIONS" in:
> > https://ww1.microchip.com/downloads/en/Appnotes/AN3474-KSZ9477-High-Availability-Seamless-Redundancy-Application-Note-00003474A.pdf
>
> Ok, so the limitation is a race condition in hardware such that, when
> duplicate packets are received on member ports very close in time to
> each other, the hardware fails to detect that they're duplicates.

It would be good to leave at least the link as part of the comment,
if not also a short summary (in case the PDF URL gets moved/removed).