Linux Kernel Upstream Release Notes v6.18

Changes and New Features

Upstream Kernel 6.18

Internal Ref.

Feature

Description

Support Added in User Space Version

Support Added in Firmware Version

Core

4314703

Support LAG Net Namespace

[All HCAs] Added LAG support for net namespace isolation. hardware LAG forms only between mlx5 interfaces that share the same network namespace. This avoids cross-namespace interference and matches user expectations when devices are placed in different netns. For example: creating a LAG when a user is passing an entire NIC PFs to a container.

N/A

N/A

4279288

NIC Availability Monitoring Counters in Devlink Interface

[ConnectX-8 and above] Added support for three new counters:

  • bar_uar_access

  • odp_local_triggered_page_fault

  • odp_remote_triggered_page_fault

The counters are exposed to the user through the devlink vnic_reporter interface. This change allows users to monitor per function usage of certain resources that may be involved in a DoS attack.

N/A

xx.47.0368

Net Dev

4533359

RS-FEC Histogram Statics

[ConnectX-7] Added support for reporting RS-FEC histogram statistics through ethtool. These histograms are defined by IEEE 802.3 and present the distribution of corrected codewords based on the number of symbol errors corrected per block, helping diagnose link quality and detect early signal degradation.

N/A

N/A

4373543

Doorbells Number

[All HCAs] Increased the number of doorbells from 1 to 8, assigned in a round-robin fashion to channel send and receive queues. This increases scalability on systems with many cores and high packet rates by reducing MMIO-contention for doorbell addresses.

N/A

N/A

4322159

PTP

[ConnectX-5 and above] Added support in the PTP subsystem and driver to expose the raw free-running cycle counter of PTP hardware clocks. This allows user space to retrieve (cycle, system-time) pairs through new ioctls and correlate hardware cycle timestamps with host time without requiring PHC synchronization.

N/A

N/A

4318230

Support PCIe Congestion Events

[ConnectX-7 and ConnectX-8] Added support for receiving and exposing PCIe congestion events as ethtool counters. PCIe congestion events are events generated by the firmware when the device side has sustained PCIe inbound or outbound traffic above certain thresholds.

N/A

28.45.1300

RDMA

4444316

Flow Steering Rules

[All HCAs] Added support for creating flow steering rules using bulk counter objects.

rdma-core

N/A

3671725

IB Service Record Resolution

[All HCAs] Added support for APIs to resolve and query destination IB address information from IB service name or ID.

Linux-6.18-rc1, rdma-core 60.0

N/A

Security

4088978

Support RSS for IPSec Offload

[ConnectX-6Dx and above] Added support for identifying the inner protocol of decrypted packets in firmware. Added new flow groups and steering rules to redirect them for proper L4-based RSS.

This ensures traffic is spread across multiple CPU cores.

N/A

xx.46.288

4034941

PSP Security Protocol

[ConnectX-7 and above] Added PSP Security Protocol support to the core, including implementation in the mlx5 driver.

N/A

xx.45.1020

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