On Friday, October 30, Remco wrote:
> I don't know if this is still relevant but I noticed that the Pentium III
> processor serial number isn't disabled for model 8 processors.
> (patch was tested on 4.6-STABLE)
>
> Index: sys/arch/i386/i386/machdep.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/i386/i386/machdep.c,v
> retrieving revision 1.453
> diff -u -r1.453 machdep.c
> --- sys/arch/i386/i386/machdep.c 15 Jun 2009 17:01:26 -0000 1.453
> +++ sys/arch/i386/i386/machdep.c 30 Oct 2009 11:18:07 -0000
> @@ -1489,7 +1489,8 @@
> /*
> * Disable the Pentium3 serial number.
> */
> - if ((model == 7) && (ci->ci_feature_flags & CPUID_SER)) {
> + if ( ((model == 7) || (model == 8)) &&
> + (ci->ci_feature_flags & CPUID_SER) ) {
> msr119 = rdmsr(MSR_BBL_CR_CTL);
> msr119 |= 0x0000000000200000LL;
> wrmsr(MSR_BBL_CR_CTL, msr119);
This does look right. However, I'm inclined not to bother.
The "serial number will track me and invade my privacy" lore
has largely died down (at least wrt CPUs). The chances of
this nuking an "innocent" model 8 that did not have the PSN
anymore, and re-tasked that un-documented bit as something
else makes me think that the risk (while low) is higher than
the benefit (which I believe is non-existant).
Your BIOS should have means to turn the PSN off, which is
the right place to be doing this.
--Toby.
