Re: [PATCH net-next] net: stmmac: enable RPS and RBU interrupts

Russell King (Oracle)
2026-04-13T20:53:34Z

On Mon, Apr 13, 2026 at 01:50:18PM -0700, Jakub Kicinski wrote:
> On Mon, 13 Apr 2026 19:49:46 +0100 Russell King (Oracle) wrote:
> > > Firing interrupts when Rx fill ring runs dry (which IIUC this patches
> > > dies?) is not a good idea.
> >
> > Well, I'm thinking that at least on some platforms, such as the Jetson
> > Xavier NX, unless a different solution can be found, we need the RBU
> > interrupt to fire off a reset of the stmmac IP when this happens to
> > reduce the PAUSE frame flood on the network.
> >
> > If we can't do that, then I think stmmac on these platforms needs to be
> > marked with CONFIG_BROKEN because right now there doesn't seem to be any
> > other viable solution.
> >
> > My intention with this patch is merely to start collecting the already
> > existing statistics so other users can start seeing whether they are
> > hitting the same or similar problem. If we're not prepared to do that,
> > then we should delete the useless statistics from ethtool -S, but I
> > suspect they're now part of the UAPI, even though without this patch
> > they will remain stedfastly stuck at zero.
>
> Understood, thanks for the extra context. And the statistic we are
> talking about is rx_buf_unav_irq ?

Yes, correct.