Re: [PATCH net-next] ptp: add vclock timestamp conversion IOCTL

[Richard Cochran]

On Fri, Oct 08, 2021 at 09:13:58AM +0200, Sebastien Laveze wrote:
> On Thu, 2021-10-07 at 13:19 -0700, Richard Cochran wrote:

> > If two independent processes are both adjusting a clock concurrently,
> > asynchronously, and at different control rates, the result will be
> > chaos.
> 
> This is especially what we want to prove feasible and we think it's
> posssible with the following conditions:
> -limited frequency adjustments
> -offset adjustment in software

Sorry, the kernel still must function correctly, even when user space
does crazy stuff.

> > It does not matter that it *might* work for some random setup of
> > yours.
> > 
> > The kernel has to function correctly in general, not just in some
> > special circumstances.
> 
> Of course, so what tests and measurements can we bring on the table to
> convince you that it doesn't lead to chaos ?

Show that it always works, even with worst case crazy adjustments.

Thanks,
Richard