Re: [PATCH] cpu/cpuid: check CPUID_PAE to determine 36 bit processor address space

[Michael S. Tsirkin]

On Tue, Sep 12, 2023 at 05:36:50PM +0530, Ani Sinha wrote:
> PAE mode in x86 supports 36 bit address space. Check the PAE CPUID on the
> guest processor and set phys_bits to 36 if PAE feature is set. This is in
> addition to checking the presence of PSE36 CPUID feature for setting 36 bit
> phys_bits.
> 
> Signed-off-by: Ani Sinha <anisinha@redhat.com>

Acked-by: Michael S. Tsirkin <mst@redhat.com>

who's applying this?

> ---
>  target/i386/cpu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Note: Not sure what tests I should be running in order to make sure I am
> not breaking any guest OSes. Usual qtests pass.
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 24ee67b42d..f3a5c99117 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -7375,7 +7375,7 @@ static void x86_cpu_realizefn(DeviceState *dev, Error 
> **errp)
>              return;
>          }
>  
> -        if (env->features[FEAT_1_EDX] & CPUID_PSE36) {
> +        if (env->features[FEAT_1_EDX] & (CPUID_PSE36 | CPUID_PAE)) {
>              cpu->phys_bits = 36;
>          } else {
>              cpu->phys_bits = 32;
> -- 
> 2.39.1