[PATCH 1/5] powerpc/pseries: do not use msgsndp doorbells on POWER9 guests

[Nicholas Piggin]

On Sun, 09 Apr 2017 18:03:35 +1000
Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:

> On Fri, 2017-04-07 at 22:55 +1000, Nicholas Piggin wrote:
> > POWER9 hypervisors will not necessarily run guest threads together on
> > the same core at the same time, so msgsndp should not be used.  
> 
> Maybe we shouldn't advertise doorbells at all ?

Possibly not. I don't know if there is a good way to switch it off
in the guest from the host with device tree currently. Might be better
to clear it early in the guest rather than test it here though?

Thanks,
Nick