mlx4_core module is not loading in Red Hat Enterprise Linux Realtime kernel.

Solution Verified - Updated -


  • Red Hat Enterprise Linux Server (RHEL) 6.5
  • Red Hat Enterprise MRG 2.5
  • Mellanox Technologies MT27500 Family
  • libmlx4-rocee-1.0.5-1.1.el6_5.x86_64


  • mlx4_core driver failed to load in RHEL 6.
  • Why mlx4_core: 1' invalid for parameter hpn' message is seen in dmesg file ?
  • Manual loading of mlx4_core shows :
mlx4_core: `1' invalid for parameter `hpn'
FATAL: Error inserting mlx4_core (/lib/modules/3.10.0-229.rt56.162.el6rt.x86_64/kernel/drivers/net/ethernet/mellanox/mlx4/mlx4_core.ko): Invalid argument
FATAL: Error running install command for mlx4_core


  • Update the kernel to kernel-rt-3.10.0-657.rt56.574.el6rt or above versions. If updating the kernel is not feasible you can follow the workaround:

Workaround :

  • Open the file /etc/modprobe.d/libmlx4.conf and comment out the below line :
options mlx4_core hpn=1
  • After modification the file will be :
# cat etc/modprobe.d/libmlx4.conf 
install mlx4_core /sbin/modprobe --ignore-install mlx4_core && (if [ -f /usr/libexec/ -a -f /etc/rdma/mlx4.conf ]; then /usr/libexec/ < /etc/rdma/mlx4.conf; fi; /sbin/modprobe mlx4_en; /sbin/modprobe mlx4_ib)
  • Now restart the system.

Diagnostic Steps

  • The network interface does not detected or not seen in ip a command :
# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
  • The network interface driver(mlx4_en) is not loaded :
# lsmod | grep mlx4_en
  • Manual loading of the driver(mlx4_en) shows error :
# modprobe mlx4_en
FATAL: Error inserting mlx4_en (lib/modules/3.10.0-229.rt56.162.el6rt.x86_64/kernel/drivers/net/ethernet/mellanox/mlx4/mlx4_en.ko): Unknown symbol in module, or unknown parameter (see dmesg)

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