Re: [PATCH V2 2/25] x86/cpu: Add helper functions to get parameters of hybrid CPUs

[Borislav Petkov]

On Wed, Mar 10, 2021 at 08:37:38AM -0800, kan.liang@xxxxxxxxxxxxxxx wrote:
> From: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
> 
> On processors with Intel Hybrid Technology (i.e., one having more than one
> type of CPU in the same package), all CPUs support the same instruction
> set and enumerate the same features on CPUID. Thus, all software can run
> on any CPU without restrictions. However, there may be model-specific
> differences among types of CPUs. For instance, each type of CPU may support
> a different number of performance counters. Also, machine check error banks
> may be wired differently. Even though most software will not care about
> these differences, kernel subsystems dealing with these differences must
> know. Add a new member to cpuinfo_x86 that subsystems can query to know
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

That is not the case anymore.

And it looks like the IPIing is going away too, which is good.

Thx.

-- 
Regards/Gruss,
    Boris.

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