Soft-RoCE in qemu on CentOS 7?

[Matthias Leopold]

Hi,

I don't know if this really the right place to ask but I want to know if 
Soft-RoCE 
(https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/networking_guide/sec-configuring_soft-_roce) 
is supposed to work between VMs that are running in qemu on CentOS 7 
hypervisor hosts.

I found two posts which explain my problem (ibv_rc_pingpong fails with a 
"Failed to modify QP to RTR"):
https://lists.openfabrics.org/pipermail/users/2019-May/000729.html (he's 
probably using Virtualbox)
https://mymellanox.force.com/mellanoxcommunity/s/feed/0D51T00006jCUWYSA4

I also found this:
https://github.com/qemu/qemu/blob/master/docs/pvrdma.txt
which I can't use at the moment, but I'm not even sure I would really 
need this.
I would be happy if someone could just confirm if "Soft-RoCE in qemu on 
CentOS 7" works or not.

thank you very much
Matthias