The RSS kselftests fail on stmmac, and this is partly due to the driver reporting bogus data for the RSS ops : - ethtool -x reports an indirection table and a key while the hardware doesn't have any of that - ethtool -X fails with -EINVAL. Let's return early in the rss ops if we know the hardware and platform don't support RSS. Note that RSS is currently not supported on any devices upstream, so code that was already useless is now effectively dead. It has been the case since 2019 when the code was added, as platforms need to set rss_en in their plat data, and no glue ever did that. Russell King ran a poll in february 2026 [1] asking if the code should be dropped, without any reply going in either direction. Jitendra Vegiraju from Broadcom sent 9 iterations of a Broadcom PCIe glue driver [2] that actually sets rss_en = 1, so there's some hope that this may be used in the future. [1] : https://lore.kernel.org/netdev/aYd4BkAeNW6d0iIC@shell.armlinux.org.uk/ [2] : https://lore.kernel.org/netdev/20260402213629.1996133-1-jitendra.vegiraju@broadcom.com/ Fixes: 76067459c686 ("net: stmmac: Implement RSS and enable it in XGMAC core") Signed-off-by: Maxime Chevallier --- Jitendra, do you have plans to continue iterating on the BCM8958x glue ? Thanks, Maxime drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c index 1be5310ca766..4e917a448271 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c @@ -927,6 +927,9 @@ static u32 stmmac_get_rxfh_key_size(struct net_device *dev) { struct stmmac_priv *priv = netdev_priv(dev); + if (!priv->dma_cap.rssen || !priv->plat->rss_en) + return 0; + return sizeof(priv->rss.key); } @@ -934,6 +937,9 @@ static u32 stmmac_get_rxfh_indir_size(struct net_device *dev) { struct stmmac_priv *priv = netdev_priv(dev); + if (!priv->dma_cap.rssen || !priv->plat->rss_en) + return 0; + return ARRAY_SIZE(priv->rss.table); } @@ -943,6 +949,9 @@ static int stmmac_get_rxfh(struct net_device *dev, struct stmmac_priv *priv = netdev_priv(dev); int i; + if (!priv->dma_cap.rssen || !priv->plat->rss_en) + return -EOPNOTSUPP; + if (rxfh->indir) { for (i = 0; i < ARRAY_SIZE(priv->rss.table); i++) rxfh->indir[i] = priv->rss.table[i]; @@ -962,6 +971,9 @@ static int stmmac_set_rxfh(struct net_device *dev, struct stmmac_priv *priv = netdev_priv(dev); int i; + if (!priv->dma_cap.rssen || !priv->plat->rss_en) + return -EOPNOTSUPP; + if (rxfh->hfunc != ETH_RSS_HASH_NO_CHANGE && rxfh->hfunc != ETH_RSS_HASH_TOP) return -EOPNOTSUPP; -- 2.55.0