Re: [PATCH v4 9/9] KVM: VMX: Consolidate the exit handler for VMX and TDX

[Nikolay Borisov]

On 8/19/26 12:49, Xiaoyao Li wrote:
> The exit handlers for VMX and TDX have the similar pattern. Consolidate
> them into a single vt_handle_exit() helper.
>
> Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
> Changes in v4:
> - new patch.
> ---
>   arch/x86/kvm/vmx/main.c | 38 ++++++++++++++++++++++++++++----------
>   arch/x86/kvm/vmx/tdx.c  | 18 +-----------------
>   arch/x86/kvm/vmx/vmx.c  | 21 +--------------------
>   3 files changed, 30 insertions(+), 47 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 6a813c49ca8a..10df9667d0c0 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -154,15 +154,6 @@ static fastpath_t vt_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags)
>   	return vmx_vcpu_run(vcpu, run_flags);
>   }
>   
> -static int vt_handle_exit(struct kvm_vcpu *vcpu,
> -			  enum exit_fastpath_completion fastpath)
> -{
> -	if (is_td_vcpu(vcpu))
> -		return tdx_handle_exit(vcpu, fastpath);
> -
> -	return vmx_handle_exit(vcpu, fastpath);
> -}
> -
>   static bool vt_unhandleable_emulation_required(struct kvm_vcpu *vcpu)
>   {
>   	if (is_td_vcpu(vcpu)) {
> @@ -887,6 +878,33 @@ int vt_handle_bus_lock_vmexit(struct kvm_vcpu *vcpu)
>   	return 1;
>   }
>   
> +static int vt_handle_exit(struct kvm_vcpu *vcpu,
> +			  enum exit_fastpath_completion fastpath)
> +{
> +	int ret;
> +
> +#ifdef CONFIG_KVM_INTEL_TDX
> +	if (is_td_vcpu(vcpu))
> +		ret = tdx_handle_exit(vcpu, fastpath);
> +	else
> +#endif
> +		ret = vmx_handle_exit(vcpu, fastpath);
> +
> +	/*
> +	 * Exit to user space when bus lock detected to inform that there is
> +	 * a bus lock in guest.
> +	 */
> +	if (vmx_get_exit_reason(vcpu).bus_lock_detected) {
> +		if (ret > 0) {
> +			vcpu->run->exit_reason = KVM_EXIT_X86_BUS_LOCK;
> +			ret = 0;
> +		}
> +
> +		vcpu->run->flags |= KVM_RUN_X86_BUS_LOCK;
> +	}
> +	return ret;
> +}
> +
>   #define VMX_REQUIRED_APICV_INHIBITS				\
>   	(BIT(APICV_INHIBIT_REASON_DISABLED) |			\
>   	 BIT(APICV_INHIBIT_REASON_ABSENT) |			\
> @@ -960,7 +978,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>   
>   	.vcpu_needs_initialization = vt_op_tdx_only(vcpu_needs_initialization),
>   	.vcpu_run = vt_op(vcpu_run),
> -	.handle_exit = vt_op(handle_exit),
> +	.handle_exit = vt_handle_exit,

nit: Why isn't this vt_op() for the sake of consistency and introduce 
needless churn ?

<snip>