On Wed, 2010-06-30 at 10:53 +0200, Stefan Assmann wrote:

From: Stefan Assmann <redacted>

It looks like the VFs get initialized before all the PFs are. Therefore
the udev mapping MAC <-> ethX (for PFs) gets screwed because the VFs
may grab the ethX interface names (reserved by udev) for the PFs.

Example:
igb max_vfs=0
eth0      Link encap:Ethernet  HWaddr 00:13:20:F7:A5:9E
eth1      Link encap:Ethernet  HWaddr 00:13:20:F7:A5:9F
eth2      Link encap:Ethernet  HWaddr 00:13:20:F7:A5:A0
eth3      Link encap:Ethernet  HWaddr 00:13:20:F7:A5:A1
igb max_vfs=1
eth0      Link encap:Ethernet  HWaddr 00:13:20:F7:A5:9E
eth1      Link encap:Ethernet  HWaddr 0A:CF:41:69:F7:A9
eth2      Link encap:Ethernet  HWaddr 3A:FE:20:4C:2A:3B
eth3      Link encap:Ethernet  HWaddr C6:C3:B1:56:C9:A4
eth3_rename Link encap:Ethernet  HWaddr 00:13:20:F7:A5:9F
eth4      Link encap:Ethernet  HWaddr 6E:8A:8A:A3:5F:69
eth4_rename Link encap:Ethernet  HWaddr 00:13:20:F7:A5:A0
eth5_rename Link encap:Ethernet  HWaddr 00:13:20:F7:A5:A1

In the example above VF 0A:CF:41:69:F7:A9 grabs eth1 but udev
has a rule that says eth1 should be assigned PF 00:13:20:F7:A5:9F
(eth3_rename) and waits for the VF to disappear to rename eth3_rename
to eth1. Unfortunately eth1 is not going to disappear.
This is not a udev bug since udev doesn't create persistent rules for
VFs as their MAC address changes every reboot.

[...]

I think it is a bug in the udev rules: udev should rename the VFs even
though their names won't be persistent.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.