On Wed, Dec 04, 2019 at 04:34:45PM +0100, Paolo Bonzini wrote: > On 04/12/19 16:07, Catherine Ho wrote: > >> Ok, so the problem is that some MSR didn't exist in that version. Which > > I thought in my platform, the only MSR didn't exist is MSR_IA32_VMX_BASIC > > (0x480). If I remove this kvm_msr_entry_add(), everything is ok, the guest can > > be boot up successfully. > > > > MSR_IA32_VMX_BASIC was added in kvm-4.10. Maybe the issue is the > _value_ that is being written to the VM is not valid? Can you check > what's happening in vmx_restore_vmx_basic? I believe env->features[FEAT_VMX_BASIC] will be initialized to 0 if the host kernel doesn't have KVM_CAP_GET_MSR_FEATURES. -- Eduardo