Re: [patch-2.3.46-p2] P6 microcode update support

[Tigran Aivazian]

Rogier Wolff wrote:
> .... On the other hand, you don't know what is "below" the 5, as the
> BIOS may have upgraded a stepping 3 CPU to a stepping 5. Short of
> intercepting the CPU right after reset there is nothing you can do to
> determine the hardware level, right?

no, I don't think so. Check section 8.10.3 which shows how to determine
the original signature and the update signature. The idea is to use 0x8B
MSR via rdmsr and after cpuid and compare the result. 

Besides one also has the signatures in processor entries of MP table. Do
they get updated as well? I haven't tried it yesterday. Will try
tonight.

Regards,
Tigran.