Re: [PATCH net-next V2] ptp: fix corrupted list in ptp_open

[Richard Cochran]

On Fri, Nov 03, 2023 at 07:13:31PM -0700, Richard Cochran wrote:
> See ptp_clock.c:
> 
>  416         case PTP_CLOCK_EXTTS:
>  417                 /* Enqueue timestamp on selected queues */
>  418                 list_for_each_entry(tsevq, &ptp->tsevqs, qlist) {
>  419                         if (test_bit((unsigned int)event->index, tsevq->mask))
>  420                                 enqueue_external_timestamp(tsevq, event);
>  421                 }
>  422                 wake_up_interruptible(&ptp->tsev_wq);
>  423                 break;

And that code can be called from interrupt context.

Thus the mutex won't work.

It needs to be a spin lock instead.

Thanks,
Richard