2021-06-06 05:37:59

by Eli Cohen

Subject: [PATCH v2] vdpa/mlx5: Clear vq ready indication upon device reset

After device reset, the virtqueues are not ready so clear the ready
field.

Failing to do so can result in virtio_vdpa failing to load if the device
was previously used by vhost_vdpa and the old values are ready.
virtio_vdpa expects to find VQs in "not ready" state.

Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Signed-off-by: Eli Cohen <[email protected]>
---
v0 --> v1:
Make sure clear of ready is done only in reset flow
v1 --> v2:
use ascending loop iterator to avoid confusion

drivers/vdpa/mlx5/net/mlx5_vnet.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 02a05492204c..a42db592e7bb 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1766,6 +1766,14 @@ static void teardown_driver(struct mlx5_vdpa_net *ndev)
mutex_unlock(&ndev->reslock);
}

+static void clear_vqs_ready(struct mlx5_vdpa_net *ndev)
+{
+ int i;
+
+ for (i = 0; i < ndev->mvdev.max_vqs; i++)
+ ndev->vqs[i].ready = false;
+}
+
static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
{
struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
@@ -1776,6 +1784,7 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
if (!status) {
mlx5_vdpa_info(mvdev, "performing device reset\n");
teardown_driver(ndev);
+ clear_vqs_ready(ndev);
mlx5_vdpa_destroy_mr(&ndev->mvdev);
ndev->mvdev.status = 0;
ndev->mvdev.mlx_features = 0;
--
2.31.1

2021-06-07 02:15:51

by Jason Wang

Subject: Re: [PATCH v2] vdpa/mlx5: Clear vq ready indication upon device reset

?? 2021/6/6 ????1:31, Eli Cohen д??:
> After device reset, the virtqueues are not ready so clear the ready
> field.
>
> Failing to do so can result in virtio_vdpa failing to load if the device
> was previously used by vhost_vdpa and the old values are ready.
> virtio_vdpa expects to find VQs in "not ready" state.
>
> Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
> Signed-off-by: Eli Cohen <[email protected]>


Acked-by: Jason Wang <[email protected]>


> ---
> v0 --> v1:
> Make sure clear of ready is done only in reset flow
> v1 --> v2:
> use ascending loop iterator to avoid confusion
>
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 02a05492204c..a42db592e7bb 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -1766,6 +1766,14 @@ static void teardown_driver(struct mlx5_vdpa_net *ndev)
> mutex_unlock(&ndev->reslock);
> }
>
> +static void clear_vqs_ready(struct mlx5_vdpa_net *ndev)
> +{
> + int i;
> +
> + for (i = 0; i < ndev->mvdev.max_vqs; i++)
> + ndev->vqs[i].ready = false;
> +}
> +
> static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
> {
> struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
> @@ -1776,6 +1784,7 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
> if (!status) {
> mlx5_vdpa_info(mvdev, "performing device reset\n");
> teardown_driver(ndev);
> + clear_vqs_ready(ndev);
> mlx5_vdpa_destroy_mr(&ndev->mvdev);
> ndev->mvdev.status = 0;
> ndev->mvdev.mlx_features = 0;