MSR_KGSBASE
wrmsr(MSR_KGSBASE, 0); /* User value while in the kernel */
pcb->pcb_gsbase = rdmsr(MSR_KGSBASE);
wrmsr(MSR_KGSBASE, 0); /* User value */
rdmsr(MSR_FSBASE), rdmsr(MSR_GSBASE), rdmsr(MSR_KGSBASE));
gsbase = rdmsr(MSR_KGSBASE);
wrmsr(MSR_KGSBASE, 0); /* User value while we're in the kernel */
svm_msr_rw_ok(svm_sc->msr_bitmap, MSR_KGSBASE);
guest_msr_rw(vmx, MSR_KGSBASE);
wrmsr(MSR_KGSBASE, vcpu->guest_msrs[IDX_MSR_KGSBASE]);
vcpu->guest_msrs[IDX_MSR_KGSBASE] = rdmsr(MSR_KGSBASE);
case MSR_KGSBASE: