在 2023/11/30 下午5:33, Paolo Abeni 写道:
On Mon, 2023-11-27 at 10:55 +0800, Heng Qi wrote:
@@ -4738,11 +4881,14 @@ static void remove_vq_common(struct virtnet_info *vi)
static void virtnet_remove(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
+ int i;
virtnet_cpu_notif_remove(vi);
/* Make sure no work handler is accessing the device. */
flush_work(&vi->config_work);
+ for (i = 0; i < vi->max_queue_pairs; i++)
+ cancel_work(&vi->rq[i].dim.work);
If the dim work is still running here, what prevents it from completing
after the following unregister/free netdev?
Yes, no one here is trying to stop it, the situation is like
unregister/free netdev
when rss are being set, so I think this is ok.
It looks like you want need to call cancel_work_sync here?
In v4, Yinjun Zhang mentioned that _sync() can cause deadlock[1].
Therefore, cancel_work() is used here instead of cancel_work_sync() to
avoid possible deadlock.
[1]
https://lore.kernel.org/all/20231122092939.1005591-1-yinjun.zhang@xxxxxxxxxxxx/
Additionally the later remove_vq_common() will needless call
cancel_work() again;
Yes. remove_vq_common() now does not call cancel_work().
possibly is better to consolidate a single (sync)
call there.
Do you mean add it in virtnet_freeze()?
cancel_work() has existed in the path virtnet_freeze() ->
virtnet_freeze_down() -> virtnet_close().
Thanks!
Cheers,
Paolo
