From 5b47b402f5833bf10b00dc2e582e986aa66cf2fc Mon Sep 17 00:00:00 2001 From: Jesse Brandeburg Date: Mon, 1 Dec 2025 15:38:52 -0800 Subject: [PATCH] ice: stop counting UDP csum mismatch as rx_errors [ Upstream commit 05faf2c0a76581d0a7fdbb8ec46477ba183df95b ] Since the beginning, the Intel ice driver has counted receive checksum offload mismatches into the rx_errors member of the rtnl_link_stats64 struct. In ethtool -S these show up as rx_csum_bad.nic. I believe counting these in rx_errors is fundamentally wrong, as it's pretty clear from the comments in if_link.h and from every other statistic the driver is summing into rx_errors, that all of them would cause a "hardware drop" except for the UDP checksum mismatch, as well as the fact that all the other causes for rx_errors are L2 reasons, and this L4 UDP "mismatch" is an outlier. A last nail in the coffin is that rx_errors is monitored in production and can indicate a bad NIC/cable/Switch port, but instead some random series of UDP packets with bad checksums will now trigger this alert. This false positive makes the alert useless and affects us as well as other companies. This packet with presumably a bad UDP checksum is *already* passed to the stack, just not marked as offloaded by the hardware/driver. If it is dropped by the stack it will show up as UDP_MIB_CSUMERRORS. And one more thing, none of the other Intel drivers, and at least bnxt_en and mlx5 both don't appear to count UDP offload mismatches as rx_errors. Here is a related customer complaint: https://community.intel.com/t5/Ethernet-Products/ice-rx-errros-is-too-sensitive-to-IP-TCP-attack-packets-Intel/td-p/1662125 Fixes: 4f1fe43c920b ("ice: Add more Rx errors to netdev's rx_error counter") Cc: Tony Nguyen Cc: Jake Keller Cc: IWL Signed-off-by: Jesse Brandeburg Acked-by: Jacob Keller Signed-off-by: Tony Nguyen Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/ice/ice_main.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c index 04e3f6c424c0..db5319a8eb24 100644 --- a/drivers/net/ethernet/intel/ice/ice_main.c +++ b/drivers/net/ethernet/intel/ice/ice_main.c @@ -5841,7 +5841,6 @@ void ice_update_vsi_stats(struct ice_vsi *vsi) pf->stats.illegal_bytes + pf->stats.rx_len_errors + pf->stats.rx_undersize + - pf->hw_csum_rx_error + pf->stats.rx_jabber + pf->stats.rx_fragments + pf->stats.rx_oversize;