[PATCH 4.19 25/92] net: ethernet: stmmac: Disable hardware multicast filter

From: Greg Kroah-Hartman
Date: Thu Aug 20 2020 - 05:53:06 EST


From: Jonathan McDowell <noodles@xxxxxxxx>

commit df43dd526e6609769ae513a81443c7aa727c8ca3 upstream.

The IPQ806x does not appear to have a functional multicast ethernet
address filter. This was observed as a failure to correctly receive IPv6
packets on a LAN to the all stations address. Checking the vendor driver
shows that it does not attempt to enable the multicast filter and
instead falls back to receiving all multicast packets, internally
setting ALLMULTI.

Use the new fallback support in the dwmac1000 driver to correctly
achieve the same with the mainline IPQ806x driver. Confirmed to fix IPv6
functionality on an RB3011 router.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jonathan McDowell <noodles@xxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
@@ -350,6 +350,7 @@ static int ipq806x_gmac_probe(struct pla
plat_dat->has_gmac = true;
plat_dat->bsp_priv = gmac;
plat_dat->fix_mac_speed = ipq806x_gmac_fix_mac_speed;
+ plat_dat->multicast_filter_bins = 0;

err = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
if (err)