Re: [Qemu-devel] vhost-user: VHOST_SET_MEM_TABLE, VHOST_SET_VRING_CALL need a reply?

[Linhaifeng]

I think maybe is not need for the backend to wait for response.

There is another way.vhost-user send "VHOST_GET_MEM_TABLE" to qemu then qemu 
send VHOST_SET_MEM_TABLE to update the regions of vhost-user.same as other 
command.
If qemu could response the request of the vhost-user.the vhost-user could 
update date at anytime.

I think it's very useful for Commercialization.

On 2014/9/17 16:38, Michael S. Tsirkin wrote:
> Reply-To: 
> 
> Thinking about the vhost-user protocol, VHOST_SET_MEM_TABLE
> is used to update the memory mappings.
> 
> So shouldn't we want for response?
> Otherwise e.g. guest can start using the memory
> that vhost-user can't access.
> 
> Similarly, with an IOMMU vhost-user might access memory it shouldn't.
> 
> VHOST_SET_VRING_CALL is used for MSI-X masking.
> Again, after vector is masted by switching the call fd,
> backend shouldn't assert the old one.
> 
> Thoughts?
> 
>