Device hints to put mlx4 on IB mode

[Vinícius Ferrão]

Hello guys,

I would like to put my Connect-X3 card in IB mode during boot time using device hints instead of sysctl's.

Today we have this dirty workarround on /etc/sysctl.conf:
sys.device.mlx4_core0.mlx4_port1=ib
sys.device.mlx4_core0.mlx4_port2=ib

It’s fine when we use a Connect-X3 card with two Infiniband interfaces, but if a ConnectX-3 card with only one interface is used an error message is dumped on the console about failing to set the "sys.device.mlx4_core0.mlx4_port2=ib” sysctl.

To solve this I would like to use device hints passed from the GRUB2 bootloader, but I was unable to find which hints I should use for the mlx4 drivers. I don’t even know if this is supported.

The problem is purely cosmetic, I just want to get rid of the error message during the boot process.

Thanks in advance,
V.