[PATCH net-next v2 0/4] net: ntb_netdev: Preserve checksum offload across NTB

From: Koichiro Den

Date: Mon Aug 17 2026 - 02:50:25 EST


Hi,

ntb_netdev may be used on embedded systems, where CPU resources are
often limited. L4 checksum calculation can therefore become a bottleneck
even when traffic stays within a trusted PCIe fabric.

This small series makes it possible to carry CHECKSUM_PARTIAL state
across the NTB link using opaque per-payload metadata in ntb_transport.
Existing peers continue to use software checksumming. The feature
remains disabled by default and must be enabled explicitly for trusted
links.

Note: the first two fixes came from Sashiko's review of v1. They touch
the same ntb_transport path as the metadata patch, so keeping them here
avoids a cross-tree dependency. With review from the NTB side, I hope
the whole series can go through net-next.

Best regards,
Koichiro
---
Changes in v2:
- Reset peer checksum capability on every link event (Sashiko)
- Add prerequisite fixes for RX ordering and shared field endianness
(Sashiko)

v1: https://lore.kernel.org/r/20260814032913.3558500-1-den@xxxxxxxxxxxxx/

Koichiro Den (4):
NTB: ntb_transport: Order RX descriptor reads after completion
NTB: ntb_transport: Use little-endian shared fields
NTB: ntb_transport: Add per-payload client metadata
net: ntb_netdev: Preserve CHECKSUM_PARTIAL across NTB

drivers/net/ntb_netdev.c | 77 +++++++++++++++++++++++++++++++++--
drivers/ntb/ntb_transport.c | 73 +++++++++++++++++++++------------
include/linux/ntb_transport.h | 6 ++-
3 files changed, 123 insertions(+), 33 deletions(-)

base-commit: e6a5d573d24cd375e09d24f136523cb3cc85c9d3
--
2.51.0