Virtualization - Mar 2021 - [RFC v4 02/11] vhost-vdpa: protect concurrent access to vhost device iotlb

On 2021/2/23 7:50 ??, Xie Yongji wrote:
> Use vhost_dev->mutex to protect vhost device iotlb from
> concurrent access.
>
> Fixes: 4c8cf318("vhost: introduce vDPA-based backend")
> Signed-off-by: Xie Yongji <xieyongji at bytedance.com>
> ---
>   drivers/vhost/vdpa.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index c50079dfb281..5500e3bf05c1 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -723,6 +723,7 @@ static int vhost_vdpa_process_iotlb_msg(struct
vhost_dev *dev,
>   	if (r)
>   		return r;
>   
> +	mutex_lock(&dev->mutex);

I think this should be done before the vhost_dev_check_owner() above.

Thanks

>   	switch (msg->type) {
>   	case VHOST_IOTLB_UPDATE:
>   		r = vhost_vdpa_process_iotlb_update(v, msg);
> @@ -742,6 +743,7 @@ static int vhost_vdpa_process_iotlb_msg(struct
vhost_dev *dev,
>   		r = -EINVAL;
>   		break;
>   	}
> +	mutex_unlock(&dev->mutex);
>   
>   	return r;
>   }