Re: [PATCH 13/30] KVM: TDX: Get TDX global information

[Huang, Kai]

On Thu, 2025-02-20 at 12:05 -0500, Paolo Bonzini wrote:
> From: Kai Huang <kai.huang@xxxxxxxxx>
> 
> KVM will need to consult some essential TDX global information to create
> and run TDX guests.  Get the global information after initializing TDX.
> 
> Signed-off-by: Kai Huang <kai.huang@xxxxxxxxx>
> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
> Message-ID: <20241030190039.77971-3-rick.p.edgecombe@xxxxxxxxx>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
>  arch/x86/kvm/vmx/tdx.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 0666dfbe0bc0..761d3a9cd5c5 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -13,6 +13,8 @@ module_param_named(tdx, enable_tdx, bool, 0444);
>  
>  static enum cpuhp_state tdx_cpuhp_state;
>  
> +static const struct tdx_sys_info *tdx_sysinfo;
> +
>  static int tdx_online_cpu(unsigned int cpu)
>  {
>  	unsigned long flags;
> @@ -90,11 +92,20 @@ static int __init __tdx_bringup(void)
>  	if (r)
>  		goto tdx_bringup_err;
>  
> +	/* Get TDX global information for later use */
> +	tdx_sysinfo = tdx_get_sysinfo();
> +	if (WARN_ON_ONCE(!tdx_sysinfo)) {
> +		r = -EINVAL;
> +		goto get_sysinfo_err;
> +	}
> +
>  	/*
>  	 * Leave hardware virtualization enabled after TDX is enabled
>  	 * successfully.  TDX CPU hotplug depends on this.
>  	 */
>  	return 0;
> +get_sysinfo_err:
> +	__do_tdx_cleanup();

We need to call __tdx_cleanup() after we fix the bug in the previous patch using
the diff I provided:

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index a889087f119f..770ac9b8b528 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -112,7 +112,7 @@ static int __init __tdx_bringup(void)
         */
        return 0;
 get_sysinfo_err:
-       __do_tdx_cleanup();
+       __tdx_cleanup();
 tdx_bringup_err:
        kvm_disable_virtualization();
        return r;