Changes and New Features

Linux Kernel Upstream Release Notes v6.6

Upstream Kernel 6.6

Internal Ref.



Support Added in User Space Version

Support Added in Firmware Version


Dynamic EQ allocation

Added a feature that modifies driver completion EQ allocation method to be dynamic (on-demand), instead of a single static allocation of all completion EQs on driver load. Meaning, only when a completion EQ is needed, the driver will allocate it, reducing the memory overhead of driver load.




VFIO P2P migration support in QEMU

[ConnectX-6 Dx and above] Added a mechanism that safely starts and stops multiple VFIO devices that might do P2P transactions between themselves. Such mechanism didn't exist before, and thus, VFIO migration was allowed only for VMs with a single VFIO device. With this mechanism, this restriction is lifted and VMs with multiple VFIO devices can be migrated, given that all devices support P2P VFIO migration.




Live migration support with IPsec full offload

[ConnectX-7 and above] Added the option to do a live migration on machine with IPsec enabled, meaning we can have a VF on VM that has a valid IPsec state and migrate it without having to remove the IPsec.




Expose max SF configure via devlink resource

[ConnectX-4 and above] Added a feature to allow user applications to view the maximum number of SFs configured on the system via general linux API, devlink resource.




Expose NIC temperature via hardware monitoring kernel API

[ConnectX-5 and above] Added a feature that exposes NIC temperature by implementing hwmon kernel API (which are the standards that the drivers follow, so that an application program can scan for entries and access thermal sensors data in a simple and consistent way via libsensors userspace library).

For each one of the supported and exposed thermal diode sensors, this feature exposes the following attributes:

1) Input temperature: the current measured temperature.

2) Highest temperature: historically, the highest temperature that have been measured.

3) Temperature label (Or name): depends on the firmware capability, if firmware doesn't support sensors naming, the fallback naming convention would be: "sensorX", where X is the HW spec (MTMP register) sensor index.

4) Temperature critical max value: refers to the high threshold of Warning Event. Will be exposed as `tempY_crit` hwmon attribute (RO attribute). For example, for ConnectX5 HCA's, this temperature value will be 105 Celsius, 10 degrees lower than the HW shutdown temperature.

5) Temperature reset history: resets the highest temperature value.


xx.39.1002 GA Rel (rel-12_39_0054)
2844159Baremetal MACsec offload
[ConnectX-7 and above] Added support for MACsec operations' offload to the HW, which yields greater performance than software counterpart, and most importantly enables sending MACsec encrypted RoCE traffic, which isn't possible in software MACsec.




Support IPSec packet offload in switchdev mode

[ConnectX-6 Dx and above] Added support for IPSec packet offload in switchdev mode.




Configuration from VM/VF for full offload transport mode

[ConnectX-6 Dx and above] Introduced two new Boolean attributes of a port function: ipsec_crypto and ipsec_packet. The goal is to provide a level of granularity

for controlling VF IPsec offload capabilities, similar to what is currently

offered in the software mode. This allows users to decide if they want both

types of IPsec offload enabled for a VF, just one of them, or none at all

(which is the default).

A hypervisor-level control parameters to set the IPsec functionality of PCI VF

devices passed through to guests. The administrator of a hypervisor host may

choose to change the settings of a port function from the defaults configured

by the device firmware.

iproute2 v6.6



Forwarding INT packets

[Connect-6 DX, Connect-7, BlueField-2, BlueField-3] Added support for matching over BTH acknowledge bit using the mlx5dv_dr API.



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