[PATCH 5.0 032/115] Revert "net/mlx5e: Enable reporting checksum unnecessary also for L3 packets"

From: Greg Kroah-Hartman
Date: Wed Apr 24 2019 - 13:34:41 EST


From: Or Gerlitz <ogerlitz@xxxxxxxxxxxx>

[ Upstream commit 8c8811d46d00d119ffbe039a6e52a0b504df1c2c ]

This reverts commit b820e6fb0978f9c2ac438c199d2bb2f35950e9c9.

Prior the commit we are reverting, checksum unnecessary was only set when
both the L3 OK and L4 OK bits are set on the CQE. This caused packets
of IP protocols such as SCTP which are not dealt by the current HW L4
parser (hence the L4 OK bit is not set, but the L4 header type none bit
is set) to go through the checksum none code, where currently we wrongly
report checksum unnecessary for them, a regression. Fix this by a revert.

Note that on our usual track we report checksum complete, so the revert
isn't expected to have any notable performance impact. Also, when we are
not on the checksum complete track, the L4 protocols for which we report
checksum none are not high performance ones, we will still report
checksum unnecessary for UDP/TCP.

Fixes: b820e6fb0978 ("net/mlx5e: Enable reporting checksum unnecessary also for L3 packets")
Signed-off-by: Or Gerlitz <ogerlitz@xxxxxxxxxxxx>
Reported-by: Avi Urman <aviu@xxxxxxxxxxxx>
Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -848,8 +848,7 @@ static inline void mlx5e_handle_csum(str

csum_unnecessary:
if (likely((cqe->hds_ip_ext & CQE_L3_OK) &&
- ((cqe->hds_ip_ext & CQE_L4_OK) ||
- (get_cqe_l4_hdr_type(cqe) == CQE_L4_HDR_TYPE_NONE)))) {
+ (cqe->hds_ip_ext & CQE_L4_OK))) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
if (cqe_is_tunneled(cqe)) {
skb->csum_level = 1;