On Sun, Nov 13, 2022 at 9:45 PM Eli Cohen <elic@xxxxxxxxxx> wrote:
>
> event_handler runs under atomic context and may not acquire reslock. We
> can still guarantee that the handler won't be called after suspend by
> clearing nb_registered, unregistering the handler and flushing the
> workqueue.
>
> Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
> ---
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 14 +++-----------
> 1 file changed, 3 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 6e6490c85be2..bebfba530247 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -2872,8 +2872,8 @@ static int mlx5_vdpa_suspend(struct vdpa_device *vdev)
> int i;
>
> down_write(&ndev->reslock);
> - mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);
> ndev->nb_registered = false;
> + mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);
I wonder why this can help anything. And if it does, we have simliar
logic in mlx5_vdpa_dev_del() do we need to fix that as well?
Thanks
> flush_workqueue(ndev->mvdev.wq);
> for (i = 0; i < ndev->cur_num_vqs; i++) {
> mvq = &ndev->vqs[i];
> @@ -3051,7 +3051,7 @@ static void update_carrier(struct work_struct *work)
> else
> ndev->config.status &= cpu_to_mlx5vdpa16(mvdev, ~VIRTIO_NET_S_LINK_UP);
>
> - if (ndev->config_cb.callback)
> + if (ndev->nb_registered && ndev->config_cb.callback)
> ndev->config_cb.callback(ndev->config_cb.private);
>
> kfree(wqent);
> @@ -3068,21 +3068,13 @@ static int event_handler(struct notifier_block *nb, unsigned long event, void *p
> switch (eqe->sub_type) {
> case MLX5_PORT_CHANGE_SUBTYPE_DOWN:
> case MLX5_PORT_CHANGE_SUBTYPE_ACTIVE:
> - down_read(&ndev->reslock);
> - if (!ndev->nb_registered) {
> - up_read(&ndev->reslock);
> - return NOTIFY_DONE;
> - }
> wqent = kzalloc(sizeof(*wqent), GFP_ATOMIC);
> - if (!wqent) {
> - up_read(&ndev->reslock);
> + if (!wqent)
> return NOTIFY_DONE;
> - }
>
> wqent->mvdev = &ndev->mvdev;
> INIT_WORK(&wqent->work, update_carrier);
> queue_work(ndev->mvdev.wq, &wqent->work);
> - up_read(&ndev->reslock);
> ret = NOTIFY_OK;
> break;
> default:
> --
> 2.38.1
>
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
