Bug 211859

Summary: Difficulties with macvlan on igc network driver
Product: Networking Reporter: pjw (pjw)
Component: OtherAssignee: Stephen Hemminger (stephen)
Status: NEW ---    
Severity: normal CC: pjw
Priority: P1    
Hardware: IA-64   
OS: Linux   
Kernel Version: 5.4.0-65-generic (x86_64) Subsystem:
Regression: No Bisected commit-id:

Description pjw@rhyme.com.au 2021-02-20 01:21:32 UTC 
Driver: igc
NIC: Ethernet controller: Intel Corporation Device 15f3 (rev 02)
Mobo: ASUS Z490-H
Firmware: 1.45 (latest from Intel)


This NIC is known to have some hardware problems, so this may be insurmountable. That said:


Creating a macvlan attached to this NIC results in failure to route Layer 2 messages correctly (specifically, DHCPOFFER). The config used was:


ip link add mvlan_name link eth_name type macvlan mode bridge


When the link is brought up, virtualbox VMs connected to the ‘mvlan_name’ interface in bridged mode can send DHCPREQUEST messages, which are sent correctly over the interface, and received by the server. The response (DHCPOFFER) is never routed to the VM.


Further, attaching the VM to the NIC interface directly in bridged mode has a similar result.


Performing exactly the same tests on a different NIC (Intel Corporation I350 Gigabit Network Connection (rev 01)), results in correct functioning: the vlan setup works, as direct VM bridging to the NIC.