Problem description:

We declare that the driver supports NO_PAUSE_ON_SUSPEND (because it is mandatory). The feature requires the driver to be tolerant to system power down transition without 'pause' command, i.e. some indicated packets might be not returned. We do not implement this (the driver does wait for all the indicated packets) and the implementation is not trivial and the RHEL VM do not support S3/S4.

More for that is that in most cases the power down transition goes without problems and all the packets returned to the driver.

The trigger for this issue is:

https://github.com/virtio-win/kvm-guest-drivers-windows/issues/1394

https://github.com/virtio-win/kvm-guest-drivers-windows/issues/1221

In case there is massive uncontrolled traffic to the adapter, the system may hang on power down transition with BSOD code 9F.

The problem exists on all the operating systems, but might be reproducible better on Win10/Server 2022