On 10/16/2023 4:52 PM, Michael S. Tsirkin wrote:
On Mon, Oct 16, 2023 at 04:33:10PM +0800, Zhu, Lingshan wrote:
On 10/13/2023 9:50 PM, Michael S. Tsirkin wrote:
On Fri, Oct 13, 2023 at 06:28:34PM +0800, Zhu, Lingshan wrote:
On 10/12/2023 9:27 PM, Jason Gunthorpe wrote:
On Thu, Oct 12, 2023 at 06:29:47PM +0800, Zhu, Lingshan wrote:
sorry for the late reply, we have discussed this for weeks in virtio mailing
list. I have proposed a live migration solution which is a config space solution.
I'm sorry that can't be a serious proposal - config space can't do
DMA, it is not suitable.
config space only controls the live migration process and config the related
facilities.
We don't use config space to transfer data.
The new added registers work like queue_enable or features.
For example, we use DMA to report dirty pages and MMIO to fetch the dirty data.
I remember in another thread you said:"you can't use DMA for any migration
flows"
And I agree to that statement, so we use config space registers to control the
flow.
Thanks,
Zhu Lingshan
Jason
If you are using dma then I don't see what's wrong with admin vq.
dma is all it does.
dma != admin vq,
Well they share the same issue that they don't work for nesting
because DMA can not be intercepted.
(hope this is not a spam to virtualization list and I try to keep this
short)
only use dma for host memory access, e.g., dirty page bitmap, no need to
intercepted.
and I think we have discussed many details in pros and cons
in admin vq live migration proposal in virtio-comment.
I am not sure we should span the discussions here, repeat them over again.
Thanks
Yea let's not.
