Date:   Fri, 27 Jan 2023 05:53:36 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Eugenio =?iso-8859-1?Q?P=E9rez?= <eperezma@redhat.com>
Cc:     leiyang@redhat.com, Laurent Vivier <lvivier@redhat.com>,
        sgarzare@redhat.com, jasowang@redhat.com,
        Zhu Lingshan <lingshan.zhu@intel.com>,
        virtualization@lists.linux-foundation.org, si-wei.liu@oracle.com,
        linux-kernel@vger.kernel.org, lulu@redhat.com,
        Gautam Dawar <gdawar@xilinx.com>, alvaro.karsz@solid-run.com
Subject: Re: [PATCH 0/2] Fix expected set_vq_state behavior on vdpa_sim
Message-ID: <20230127055303-mutt-send-email-mst@kernel.org>
References: <20230118164359.1523760-1-eperezma@redhat.com>
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On Wed, Jan 18, 2023 at 05:43:57PM +0100, Eugenio P?rez wrote:
> The use of set_vq_state is to indicate vdpa device the state of a virtqueue.
> In the case of split, it means the avail_idx.  This is mandatory for use
> cases like live migration.
> 
> However, vdpa_sim reset the vq state at vdpasim_queue_ready since it calls
> vringh_init_iotlb.
> 
> Also, to starting from an used_idx different than 0 is needed in use cases like
> virtual machine migration.  Not doing so and letting the caller set an avail
> idx different than 0 causes destination device to try to use old buffers that
> source driver already recover and are not available anymore.
> 
> This series fixes both problems allowing to migrate to a vdpa_sim_net device.

Jason problems you pointed out are all consmetic do you ack
the patchset? Or expect another revision?

> Eugenio P?rez (2):
>   vdpa_sim: not reset state in vdpasim_queue_ready
>   vringh: fetch used_idx from vring at vringh_init_iotlb
> 
>  drivers/vdpa/vdpa_sim/vdpa_sim.c |  2 ++
>  drivers/vhost/vringh.c           | 25 +++++++++++++++++++++++--
>  2 files changed, 25 insertions(+), 2 deletions(-)
> 
> -- 
> 2.31.1
>