This function still has this function for the virtio-net interface on Redhat7. You can use ethtool -K to modify the settings of this ufo.
But to Redhat8, this function was canceled.
Because some switches may not support this offload function. And for virtio-net, the UDP fragment is done from the kernel layer, or from the virtio-net driver, which is actually the implementation of the software layer. So it doesn't make much sense to use the offload function. If the offload logic is used, it will add some overhead to this code.
参考：
https://bugzilla.kernel.org/show_bug.cgi?id=207075
The UDP fragmentation offload feature of Virtio-net device can not be turned on in the VM
https://access.redhat.com/solutions/4594671