Re: [RFC v3 0/5] virtio: support packed ring

[Jason Wang]

On 2018å04æ25æ 13:15, Tiwei Bie wrote:
> Hello everyone,
>
> This RFC implements packed ring support in virtio driver.
>
> Some simple functional tests have been done with Jason's
> packed ring implementation in vhost:
>
> https://lkml.org/lkml/2018/4/23/12
>
> Both of ping and netperf worked as expected (with EVENT_IDX
> disabled). But there are below known issues:
>
> 1. Reloading the guest driver will break the Tx/Rx;

It looks like the reason is we don't sync wrap counter information 
between host and qemu through VHOST_SET/GET_VRING_BASE. And both vhost 
and qemu need to do this through encoding warp counters to higher bits 
of vhost_vring_state.num,

Thanks