MSR_FSBASE
wrmsr(MSR_FSBASE, 0);
wrmsr(MSR_FSBASE, 0);
wrmsr(MSR_FSBASE, pcb->pcb_fs);
cpudata->fsbase = rdmsr(MSR_FSBASE);
wrmsr(MSR_FSBASE, cpudata->fsbase);
svm_vcpu_msr_allow(cpudata->msrbm, MSR_FSBASE, true, true);
vmx_vmwrite(VMCS_HOST_FS_BASE, rdmsr(MSR_FSBASE));
vmx_vcpu_msr_allow(cpudata->msrbm, MSR_FSBASE, true, true);