Re: [Qemu-devel] Logging dirty pages from vhost-net in-kernel with vIOMMU

[Jason Wang]

On 2018/12/5 上午2:37, Jintack Lim wrote:
> Hi,
>
> I'm wondering how the current implementation works when logging dirty
> pages during migration from vhost-net (in kernel) when used vIOMMU.
>
> I understand how vhost-net logs GPAs when not using vIOMMU. But when
> we use vhost with vIOMMU, then shouldn't vhost-net need to log the
> translated address (GPA) instead of the address written in the
> descriptor (IOVA) ? The current implementation looks like vhost-net
> just logs IOVA without translation in vhost_get_vq_desc() in
> drivers/vhost/net.c. It seems like QEMU doesn't do any further
> translation of the dirty log when syncing.
>
> I might be missing something. Could somebody shed some light on this?


Good catch. It looks like a bug to me. Want to post a patch for this?

Thanks


> Thanks,
> Jintack