Re: [PATCH v3 0/5] Enable vdpa net migration with features depending on CVQ

[Lei Yang]

QE tested this series with MAC and MQ changes, and the guest migrated
successfully with "x-svq=off" or without this parameter.

Tested-by: Lei Yang <leiyang@redhat.com>


On Tue, Aug 22, 2023 at 4:53 PM Eugenio Pérez <eperezma@redhat.com> wrote:
>
> At this moment the migration of net features that depends on CVQ is not
> possible, as there is no reliable way to restore the device state like mac
> address, number of enabled queues, etc to the destination.  This is mainly
> caused because the device must only read CVQ, and process all the commands
> before resuming the dataplane.
>
> This series lift that requirement, sending the VHOST_VDPA_SET_VRING_ENABLE
> ioctl for dataplane vqs only after the device has processed all commands.
> ---
> v3:
> * Fix subject typo and expand message of patch ("vdpa: move
>   vhost_vdpa_set_vring_ready to the caller").
>
> v2:
> * Factor out VRING_ENABLE ioctls from vhost_vdpa_dev_start to the caller,
>   instead of providing a callback to know if it must be called or not.
> * at https://lists.nongnu.org/archive/html/qemu-devel/2023-07/msg05447.html
>
> RFC:
> * Enable vqs early in case CVQ cannot be shadowed.
> * at https://lists.gnu.org/archive/html/qemu-devel/2023-07/msg01325.html
>
> Eugenio Pérez (5):
>   vdpa: use first queue SVQ state for CVQ default
>   vdpa: export vhost_vdpa_set_vring_ready
>   vdpa: rename vhost_vdpa_net_load to vhost_vdpa_net_cvq_load
>   vdpa: move vhost_vdpa_set_vring_ready to the caller
>   vdpa: remove net cvq migration blocker
>
>  include/hw/virtio/vhost-vdpa.h |  1 +
>  hw/virtio/vdpa-dev.c           |  3 ++
>  hw/virtio/vhost-vdpa.c         | 22 +++++-----
>  net/vhost-vdpa.c               | 75 +++++++++++++++++++---------------
>  hw/virtio/trace-events         |  2 +-
>  5 files changed, 57 insertions(+), 46 deletions(-)
>
> --
> 2.39.3
>
>