mlx5_vdpa_change_map() must install the new MR before rebuilding or resuming virtqueues, because both paths read the MR keys from mvdev->mres.mr[].
If rebuilding the virtqueue resources fails, the new MR must not remain installed after its reference is released. Keep an extra reference to the old MR before replacing it. On setup failure, restore the old MR; the saved reference then becomes the map reference, while replacing the new MR drops its map reference. Make mlx5_vdpa_change_map() consume new_mr on all error paths so that set_map_data() does not release an MR already released during rollback. v2: - Keep the new MR installed while virtqueues are rebuilt. - Restore the old MR only after setup_vq_resources() fails. Signed-off-by: Weimin Xiong <[email protected]> --- diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index ad0d5fbbb..25bf1c5cd 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -3055,18 +3055,24 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_dev *mvdev, unsigned int asid) { struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev); + struct mlx5_vdpa_mr *old_mr; bool teardown = !is_resumable(ndev); int err; suspend_vqs(ndev, 0, ndev->cur_num_vqs); if (teardown) { err = save_channels_info(ndev); - if (err) + if (err) { + mlx5_vdpa_put_mr(mvdev, new_mr); return err; + } teardown_vq_resources(ndev); } + /* Keep the old MR alive in case rebuilding the VQs fails. */ + old_mr = mvdev->mres.mr[asid]; + mlx5_vdpa_get_mr(mvdev, old_mr); mlx5_vdpa_update_mr(mvdev, new_mr, asid); for (int i = 0; i < mvdev->max_vqs; i++) @@ -3074,17 +3080,22 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_dev *mvdev, MLX5_VIRTQ_MODIFY_MASK_DESC_GROUP_MKEY; if (!(mvdev->status & VIRTIO_CONFIG_S_DRIVER_OK) || mvdev->suspended) - return 0; + goto out; if (teardown) { restore_channels_info(ndev); err = setup_vq_resources(ndev, true); - if (err) + if (err) { + /* The saved reference becomes the restored map reference. */ + mlx5_vdpa_update_mr(mvdev, old_mr, asid); return err; + } } resume_vqs(ndev, 0, ndev->cur_num_vqs); +out: + mlx5_vdpa_put_mr(mvdev, old_mr); return 0; } @@ -3368,15 +3379,11 @@ static int set_map_data(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb, err = mlx5_vdpa_change_map(mvdev, new_mr, asid); if (err) { mlx5_vdpa_err(mvdev, "change map failed(%d)\n", err); - goto out_err; + return err; } } return mlx5_vdpa_update_cvq_iotlb(mvdev, iotlb, asid); - -out_err: - mlx5_vdpa_put_mr(mvdev, new_mr); - return err; } static int mlx5_vdpa_set_map(struct vdpa_device *vdev, unsigned int asid,
