Re: [net-next, v5, 02/11] ptp: support ptp physical/virtual clocks conversion

[Richard Cochran]

On Sat, Aug 07, 2021 at 05:43:32PM +0300, Vladimir Oltean wrote:
> >  3. Let the vclocks hold a reference to the underlying posix dynamic clock.
> 
> So even if the vclock holds a reference to the underlying POSIX clock,
> that won't prevent the hardware driver from unbinding, and further
> gettime() calls on the vclock from faulting, will it?

Oh, your are right.  The vclocks call the real PHC clock's methods
directly, not through the posix dynamic clock layer.

> What about:
> 
> 4. Create a device link with the vclock being a consumer and the parent
>    clock being a supplier? This way, ptp_vclock_unregister() is
>    automatically called whenever (and before) ptp_clock_unregister() is.
> 
> https://www.kernel.org/doc/html/latest/driver-api/device_link.html

Sounds promising.

Thanks,
Richard