[PATCH 2/2] powerpc/time: Only cap decrementer when watchdog is enabled

[Nicholas Piggin]

On Sat, 29 Sep 2018 11:26:07 +1000
Anton Blanchard <anton at ozlabs.org> wrote:

> If CONFIG_PPC_WATCHDOG is enabled, we always cap the decrementer to
> 0x7fffffff. As suggested by Nick, add a run time check of the watchdog
> cpumask, so if it is disabled we use the large decrementer.
> 
> Signed-off-by: Anton Blanchard <anton at samba.org>
> ---

Thanks for tracking this down. It's a fix for my breakage

a7cba02deced ("powerpc: allow soft-NMI watchdog to cover timer
interrupts with large decrementers")

Taking another look... what I had expected here is the timer subsystem
would have stopped the decrementer device after it processed the timer
and found nothing left. And we should have set DEC to max at that time.

The above patch was really intended to only cover the timer interrupt
itself locking up. I wonder if we need to add

    .set_state_oneshot_stopped = decrementer_shutdown

In our decremementer clockevent device?

Thanks,
Nick