Hmm, I have links like this on my system already: $ ls -l /sys/class/infiniband/mlx4_0/device lrwxrwxrwx 1 root root 0 2007-04-23 12:14 /sys/class/infiniband/mlx4_0/device -> ../../../devices/pci0000:00/0000:00:06.0/0000:0d:00.0 the patch actually looks sane but I don't understand why it's needed. Could you explain?