Re: [Qemu-devel] [PATCH v2 5/6] x86: fix up 32 bit phys_bits case

[Daniel P. Berrange]

On Mon, Jul 04, 2016 at 08:16:08PM +0100, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <address@hidden>
> 
> On 32 bit systems fix up phys_bits to be consistent with what
> we tell the guest; don't ever bother with using the phys_bits
> property.

> @@ -2990,6 +2986,15 @@ static void x86_cpu_realizefn(DeviceState *dev, Error 
> **errp)
>              cpu->phys_bits = host_phys_bits;
>  
>          }
> +    } else {
> +        /* For 32 bit systems don't use the user set value, but keep
> +         * phys_bits consistent with what we tell the guest.
> +         */
> +        if (env->features[FEAT_1_EDX] & CPUID_PSE36) {
> +            cpu->phys_bits = 36;
> +        } else {
> +            cpu->phys_bits = 32;
> +        }

I kind of feel like we should report an error and exit if the
user/app has provided a phys_bits property value, rather than
silently ignoring their provided value, on the basis that this
is a user/app configuration error.

Regards,
Daniel
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