Enabling the driver and kconfig options


© 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved.

mlx5 core is modular and most of the major mlx5 core driver features can be selected (compiled in/out)
at build time via kernel Kconfig flags.
Basic features, ethernet net device rx/tx offloads and XDP, are available with the most basic flags
For the list of advanced features, please see below.


This will provide the ability to add representors of mlx5 uplink and VF
ports to Bridge and offloading rules for traffic between such ports.
Supports VLANs (trunk and access modes).

CONFIG_MLX5_CORE=(y/m/n) (module mlx5_core.ko)

The driver can be enabled by choosing CONFIG_MLX5_CORE=y/m in kernel config.
This will provide mlx5 core driver for mlx5 ulps to interface with (mlx5e, mlx5_ib).


Choosing this option will allow basic ethernet netdevice support with all of the standard rx/tx offloads.
mlx5e is the mlx5 ulp driver which provides netdevice kernel interface, when chosen, mlx5e will be
built-in into mlx5_core.ko.



IPoIB offloads & acceleration support.
Requires CONFIG_MLX5_CORE_EN to provide an accelerated interface for the rdma
IPoIB ulp netdevice.


Enables offload support for TC classifier action (NET_CLS_ACT).
Works in both native NIC mode and Switchdev SRIOV mode.
Flow-based classifiers, such as those registered through
tc-flower(8), are processed by the device, rather than the
host. Actions that would then overwrite matching classification
results would then be instant due to the offload.


Enables Hardware-accelerated receive flow steering (arfs) support, and ntuple filtering.



Build support for MACsec cryptography-offload acceleration in the NIC.


Enables ethtool receive network flow classification, which allows user defined
flow rules to direct traffic into arbitrary rx queue via ethtool set/get_rxnfc API.


TLS cryptography-offload acceleration.


Ethernet SRIOV E-Switch support in ConnectX NIC. E-Switch provides internal SRIOV packet steering
and switching for the enabled VFs and PF in two available modes:


Build support for the Innova family of network cards by Mellanox Technologies.
Innova network cards are comprised of a ConnectX chip and an FPGA chip on one board.
If you select this option, the mlx5_core driver will include the Innova FPGA core and allow
building sandbox-specific client drivers.

CONFIG_MLX5_INFINIBAND=(y/n/m) (module mlx5_ib.ko)

Provides low-level InfiniBand/RDMA and RoCE support.


Ethernet Multi-Physical Function Switch (MPFS) support in ConnectX NIC.
MPFs is required for when Multi-Host configuration is enabled to allow passing
user configured unicast MAC addresses to the requesting PF.


Build support for subfunction.
Subfunctons are more light weight than PCI SRIOV VFs. Choosing this option
will enable support for creating subfunction devices.


Build support for subfuction port in the NIC. A Mellanox subfunction
port is managed through devlink. A subfunction supports RDMA, netdevice
and vdpa device. It is similar to a SRIOV VF but it doesn’t require
SRIOV support.


Build support for software-managed steering in the NIC.


Support offloading connection tracking rules via tc ct action.


Support offloading sample rules via tc sample action.


Support library for Mellanox VDPA drivers. Provides code that is
common for all types of VDPA drivers. The following drivers are planned:
net, block.


VDPA network driver for ConnectX6 and newer. Provides offloading
of virtio net datapath such that descriptors put on the ring will
be executed by the hardware. It also supports a variety of stateless
offloads depending on the actual device used and firmware version.


This provides migration support for MLX5 devices using the VFIO framework.

External options ( Choose if the corresponding mlx5 feature is required )

  • CONFIG_MLXFW: When chosen, mlx5 firmware flashing support will be enabled (via devlink and ethtool).

  • CONFIG_PTP_1588_CLOCK: When chosen, mlx5 ptp support will be enabled

  • CONFIG_VXLAN: When chosen, mlx5 vxlan support will be enabled.