Re: [PATCH net v3] net: mctp: Fix tx queue stall

[Jeremy Kerr]

Hi Jinliang,

> The tx queue can become permanently stuck in a stopped state due to a
> race condition between the URB submission path and its completion
> callback.
> 
> The URB completion callback can run immediately after usb_submit_urb()
> returns, before the submitting function calls netif_stop_queue(). If
> this occurs, the queue state management becomes desynchronized, leading
> to a stall where the queue is never woken.
> 
> Fix this by moving the netif_stop_queue() call to before submitting the
> URB. This closes the race window by ensuring the network stack is aware
> the queue is stopped before the URB completion can possibly run.

Thanks!

Acked-by: Jeremy Kerr <jk@xxxxxxxxxxxxxxxxxxxx>

Cheers,


Jeremy