> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index d46a61b..2e4e8af 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -2285,6 +2285,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int
> cpu)
> if (per_cpu(current_vmcs, cpu) != vmx->loaded_vmcs->vmcs) {
> per_cpu(current_vmcs, cpu) = vmx->loaded_vmcs->vmcs;
> vmcs_load(vmx->loaded_vmcs->vmcs);
> + indirect_branch_prediction_barrier();
> }
>
> if (!already_loaded) {
> @@ -3342,6 +3343,26 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct
> msr_data *msr_info)
> case MSR_IA32_TSC:
> kvm_write_tsc(vcpu, msr_info);
> break;
> + case MSR_IA32_PRED_CMD:
> + if (!msr_info->host_initiated &&
> + !guest_cpuid_has(vcpu, X86_FEATURE_IBPB) &&
> + !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL))
> + return 1;
> +
> + if (data & ~PRED_CMD_IBPB)
> + return 1;
> +
> + if (!data)
> + break;
> +
> + wrmsrl(MSR_IA32_PRED_CMD, PRED_CMD_IBPB);
> +
> + if (is_guest_mode(vcpu))
> + break;
Don't you want this the other way around? That is first do the disable_intercept
and then add the 'if (is_guest_mode(vcpu))' ? Otherwise the very first
MSR write from the guest is going to hit condition above and never end
up executing the disabling of the intercept?
> +
> + vmx_disable_intercept_for_msr(vmx->vmcs01.msr_bitmap,
> MSR_IA32_PRED_CMD,
> + MSR_TYPE_W);
> + break;
> case MSR_IA32_CR_PAT:
> if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) {
> if (!kvm_mtrr_valid(vcpu, MSR_IA32_CR_PAT, data))
