LGTM, thanks!

Thanks! We would probably need to add more MSRs from the OSSR, but I need to look into what would be useful.
How do you feel about adding MsrWrite? In some cases it's needed to correct Erratas and definitely needed for changing P-States/overclocking or correcting timer issues when not using HPET (there's a workaround, only applicable if the patch level is below certain version).

Reference code:

// P0 fix C001_0015 HWCR[21]=1
// Fixes timer issues when not using HPET
private bool ApplyTscWorkaround()
{
    uint eax = 0, edx = 0;

    if (cpu.ReadMsr(MSR_HWCR, ref eax, ref edx))
    {
        eax |= 0x200000;
        return cpu.WriteMsr(MSR_HWCR, eax, edx);
    }
    return false;
}