MSR_MC_CTL2_EN
if (ctl2 & MSR_MC_CTL2_EN)
ctl2 |= MSR_MC_CTL2_EN;
(ctl2 & MSR_MC_CTL2_EN) ? 1 : 0;
ctl2 = (ctl2 & (~MSR_MC_CTL2_EN)) | 1;
ctl2 |= MSR_MC_CTL2_EN;
ctl2 &= ~MSR_MC_CTL2_EN;
ctl2 |= MSR_MC_CTL2_EN;