6.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jesse Brandeburg <[email protected]> [ 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 <[email protected]> Cc: Jake Keller <[email protected]> Cc: IWL <[email protected]> Signed-off-by: Jesse Brandeburg <[email protected]> Acked-by: Jacob Keller <[email protected]> Signed-off-by: Tony Nguyen <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- 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 fc284802e2bcd..b5ebfcdc9d434 100644 --- a/drivers/net/ethernet/intel/ice/ice_main.c +++ b/drivers/net/ethernet/intel/ice/ice_main.c @@ -6993,7 +6993,6 @@ void ice_update_vsi_stats(struct ice_vsi *vsi) cur_ns->rx_errors = pf->stats.crc_errors + pf->stats.illegal_bytes + pf->stats.rx_undersize + - pf->hw_csum_rx_error + pf->stats.rx_jabber + pf->stats.rx_fragments + pf->stats.rx_oversize; -- 2.51.0
