Re: [RFC PATCH v3 04/20] x86: Handle reduction in physical address size with SME

[Tom Lendacky]

On 11/15/2016 3:33 PM, Borislav Petkov wrote:
> On Tue, Nov 15, 2016 at 03:22:45PM -0600, Tom Lendacky wrote:
>> Hmmm... I still need the ebx value from the CPUID instruction to
>> calculate the proper reduction in physical bits, so I'll still need
>> to make the CPUID call.
> 
>         if (c->extended_cpuid_level >= 0x8000001f) {
>                 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx);
> 
> 		...
> 
> just like the rest of get_cpu_cap() :)

Right, which is what the code does now.  I was looking at switching
over to the cpu_has() function and eliminate the cpuid call, but I
still need the cpuid call for the ebx value.

Thanks,
Tom

>