Re: [Qemu-devel] [PATCH v5] powerpc: add PVR mask support

[Benjamin Herrenschmidt]

On Thu, 2013-08-29 at 14:52 +1000, Paul Mackerras wrote:
> We are going to need a way to do that for pseries guests.  So for
> example if we are running on a POWER8 machine and using KVM, we would
> want to be able to tell qemu that we want a POWER7 machine and have
> qemu put 0x0f000003 in the device tree, and also tell KVM to enable
> POWER7 compatibility mode when running the guest, presumably by
> setting the PVR for the guest to 0x0f000003.  That PVR setting doesn't
> (and can't) modify the PVR seen by the guest, since the hardware
> doesn't provide any way to virtualize the PVR, but we will make it set
> the compatibility mode for the guest.
> 
> How do you think we should handle this in qemu?

And how does that relate to what we will do during reconfiguration
reboots ?

Cheers,
Ben.