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

From: Jason Wang
Date: Sun Jun 06 2021 - 22:15:31 EST



在 2021/6/6 下午1:31, Eli Cohen 写道:
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 <elic@xxxxxxxxxx>


Acked-by: Jason Wang <jasowang@xxxxxxxxxx>


---
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;