Re: [PATCH 0/2] vdpa: Add logging operatins

[Jason Wang]

Adding Eugenio and Si Wei.

On Sat, Aug 26, 2023 at 9:24 AM Jiang Dongxu <jiangdongxu1@xxxxxxxxxx> wrote:
>
> From: jiangdongxu <jiangdongxu1@xxxxxxxxxx>
>
> Currently, the vdpa device supports suspend and resume operations.
> To support vdpa device live migration, we need to support logging
> operations and device state save/load opertions.
>
> These series introduces some new operations for vdpa devices.
> They allow vdpa to enable logging while vm start live migration.
>
> And I will submit another patches about saving and loading
> vdpa device state later.

Thanks for working on this, I have several questions:

1) Is there an example implementation of the logging in the drivers?
We need a real user in order to merge this.
2) Is the logging based on IOVA or VA? How the DMA isolation is being
done with this? Do we need a SET_LOGGING_ASID uAPI for this? (We had
some discussion on this in the past).

Thanks

>
> jiangdongxu (2):
>   vdpa: add log operations
>   vhost-vdpa: add uAPI for logging
>
>  drivers/vhost/vdpa.c       | 49 ++++++++++++++++++++++++++++++++++++++
>  include/linux/vdpa.h       | 14 +++++++++++
>  include/uapi/linux/vhost.h |  4 ++++
>  3 files changed, 67 insertions(+)
>
> --
> 2.27.0
>