[dpdk-dev] Why the offloads of the guest's virtio-net network adapter are disabled when vhost-user is used?

[leo zhu <leo.zhu510@gmail.com>]

Hi all,

I am running the vhost sample application on my server.

According to the dpdk-sample-applications-user-guide.pdf, I run the Virtual
Machine with vhost-user enabled.
Following is the command that is used to run the virtual machine.






*qemu-system-x86_64 /root/leo/ubuntu-1.img -enable-kvm -m 1024 -vnc :5
-chardev \socket,id=char1,path=/root/leo/dpdk-2.0.0/examples/vhost/usvhost
-netdev type=vhost-user, \id=mynet1,chardev=char1,vhostforce -device
virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1 \-object
memory-backend-file,id=mem,size=1024M,mem-path=/dev/hugepages,share=on
-numa node,memdev=mem -mem-prealloc*

After the Virtual Machine is started, I found the offloads of the
Virtual Machine's virtio-net network adapter
are all disabled*.* The offloads status is checked with command*
ethtool -k eth0*. I try to enables the offloads with ethtool command,
but it does not work.

My questions are:

1. Can the offloads of the guest's virtio-net network adapter be
enabled when vhost-user is used?

2. If the offloads can't be enabled when vhost-user is used, what is the reason?

It will be great if someone from the forum could give the answers and clues.

Thanks.
Leo