Re: [PATCH v3 2/3] KVM: SVM: Ensure PSP module is initialized if KVM module is built-in

[Tom Lendacky <thomas.lendacky@amd.com>]

On 2/3/25 15:56, Ashish Kalra wrote:
> From: Sean Christopherson <seanjc@google.com>
> 
> The kernel's initcall infrastructure lacks the ability to express
> dependencies between initcalls, whereas the modules infrastructure
> automatically handles dependencies via symbol loading.  Ensure the
> PSP SEV driver is initialized before proceeding in sev_hardware_setup()
> if KVM is built-in as the dependency isn't handled by the initcall
> infrastructure.
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>

> ---
>  arch/x86/kvm/svm/sev.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index a2a794c32050..0dbb25442ec1 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -2972,6 +2972,16 @@ void __init sev_hardware_setup(void)
>  	    WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_FLUSHBYASID)))
>  		goto out;
>  
> +	/*
> +	 * The kernel's initcall infrastructure lacks the ability to express
> +	 * dependencies between initcalls, whereas the modules infrastructure
> +	 * automatically handles dependencies via symbol loading.  Ensure the
> +	 * PSP SEV driver is initialized before proceeding if KVM is built-in,
> +	 * as the dependency isn't handled by the initcall infrastructure.
> +	 */
> +	if (IS_BUILTIN(CONFIG_KVM_AMD) && sev_module_init())
> +		goto out;
> +
>  	/* Retrieve SEV CPUID information */
>  	cpuid(0x8000001f, &eax, &ebx, &ecx, &edx);
>