Description of problem: OVS user space component does not correctly negotiate kernel space features on RHEL 7 causing user space to incorrectly detect 'per-cpu-dispatch' mode. This causes upcalls to user space to fail as user space believes it is in 'per-cpu-dispatch' mode whereas kernel space is not. Version-Release number of selected component (if applicable): Kernel: 3.10.0-1160.el7.x86_64 OVS: latest master (https://github.com/openvswitch/ovs/commit/00d3d4a7d3750ab1d907d58894ad817febce1cf7) How reproducible: Always Steps to Reproduce: 1. /usr/local/share/openvswitch/scripts/ovs-ctl start 2. ovs-vsctl add-br br0 3. ovs-appctl dpif-netlink/dispatch-mode Actual results: ovs-system: per-cpu dispatch mode Expected results: ovs-system: per-vport dispatch mode Additional info:
After investigation, the root-cause appears to be that the RHEL7 openvswitch kernel module does not check for unsupported features.
https://patchwork.ozlabs.org/project/openvswitch/list/?series=262432