Re: [PATCH v3] vdpa/mlx5: should not activate virtq object when suspended

From: Jason Wang
Date: Wed Feb 15 2023 - 23:50:32 EST


On Wed, Feb 15, 2023 at 9:31 AM Si-Wei Liu <si-wei.liu@xxxxxxxxxx> wrote:
>
> Otherwise the virtqueue object to instate could point to invalid address
> that was unmapped from the MTT:
>
> mlx5_core 0000:41:04.2: mlx5_cmd_out_err:782:(pid 8321):
> CREATE_GENERAL_OBJECT(0xa00) op_mod(0xd) failed, status
> bad parameter(0x3), syndrome (0x5fa1c), err(-22)
>
> Fixes: cae15c2ed8e6 ("vdpa/mlx5: Implement susupend virtqueue callback")
> Cc: Eli Cohen <elic@xxxxxxxxxx>
> Signed-off-by: Si-Wei Liu <si-wei.liu@xxxxxxxxxx>
> Reviewed-by: Eli Cohen <elic@xxxxxxxxxx>
>
> ---
> v3: move suspended to struct mlx5_vdpa_dev
> v2: removed the change for improving warning message
> ---
> drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 +
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 6 +++++-
> 2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
> index 058fbe2..25fc412 100644
> --- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
> +++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
> @@ -96,6 +96,7 @@ struct mlx5_vdpa_dev {
> struct mlx5_control_vq cvq;
> struct workqueue_struct *wq;
> unsigned int group2asid[MLX5_VDPA_NUMVQ_GROUPS];
> + bool suspended;
> };
>
> int mlx5_vdpa_alloc_pd(struct mlx5_vdpa_dev *dev, u32 *pdn, u16 uid);
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 3a6dbbc6..daac3ab 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -2411,7 +2411,7 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_dev *mvdev,
> if (err)
> goto err_mr;
>
> - if (!(mvdev->status & VIRTIO_CONFIG_S_DRIVER_OK))
> + if (!(mvdev->status & VIRTIO_CONFIG_S_DRIVER_OK) || mvdev->suspended)

One more thought,

Does this mean set_map() is forbidden during suspending? I'm not sure
this is correct or at least we need restrict in in the vDPA core.

Thanks

> goto err_mr;
>
> restore_channels_info(ndev);
> @@ -2579,6 +2579,7 @@ static int mlx5_vdpa_reset(struct vdpa_device *vdev)
> clear_vqs_ready(ndev);
> mlx5_vdpa_destroy_mr(&ndev->mvdev);
> ndev->mvdev.status = 0;
> + ndev->mvdev.suspended = false;
> ndev->cur_num_vqs = 0;
> ndev->mvdev.cvq.received_desc = 0;
> ndev->mvdev.cvq.completed_desc = 0;
> @@ -2815,6 +2816,8 @@ static int mlx5_vdpa_suspend(struct vdpa_device *vdev)
> struct mlx5_vdpa_virtqueue *mvq;
> int i;
>
> + mlx5_vdpa_info(mvdev, "suspending device\n");
> +
> down_write(&ndev->reslock);
> ndev->nb_registered = false;
> mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);
> @@ -2824,6 +2827,7 @@ static int mlx5_vdpa_suspend(struct vdpa_device *vdev)
> suspend_vq(ndev, mvq);
> }
> mlx5_vdpa_cvq_suspend(mvdev);
> + mvdev->suspended = true;
> up_write(&ndev->reslock);
> return 0;
> }
> --
> 1.8.3.1
>