User Manual

Driver FeaturesRev 2.2-1.0.1
Mellanox Technologies
128
When a MAC is ff:ff:ff:ff:ff:ff, the VF is not assigned to the port of the net device it is listed
under. In the example above, vf 38 is not assigned to the same port as p1p1, in contrast to vf0.
However, even VFs that are not assigned to the net device, could be used to set and change its
settings. For example, the following is a valid command to change the spoof check:
ip link set dev p1p1 vf 38 spoofchk on
This command will affect only the vf 38. The changes can be seen in ip link on the net device
that this device is assigned to.
4.15.6.3.4Mapping VFs to Ports using the mlnx_get_vfs.pl tool
 To map the PCI representation in BDF to the respective ports:
mlnx_get_vfs.pl
The output is as following:
BDF 0000:04:00.0
Port 1: 2
vf0 0000:04:00.1
vf1 0000:04:00.2
Port 2: 2
vf2 0000:04:00.3
vf3 0000:04:00.4
Both: 1
vf4 0000:04:00.5
4.15.6.3.5RoCE Support
RoCE is supported on Virtual Functions and VLANs may be used with it. For RoCE, the hyper-
visor GID table size is of 16 entries while the VFs share the remaining 112 entries. When the
number of
VFs is larger than 56 entries, some of them will have GID table with only a single
entry which is inadequate if VF's Ethernet device is assigned with an IP address.
When setting num_vfs in mlx4_core module parameter it is important to check that the number
of the assigned IP addresses per
VF does not exceed the limit for GID table size.
4.15.7 Running Network Diagnostic Tools on a Virtual Function
4.15.7.1 Overview
Until now, in MLNX_OFED, administrators were unable to run network diagnostics from a VF
since sending and receiving Subnet Management Packets (SMPs) from a
VF was not allowed, for
security reasons: SMPs are not restricted by network partitioning and may affect the physical net-
work topology. Moreover, even the SM may be denied access from portions of the network by
setting management keys unknown to the SM.
However, it is desirable to grant SMP capability to certain privileged VFs, so certain network
management activities may be conducted within virtual machines rather than only on the hyper-
visor.