Re: [RFC PATCH v6 011/104] KVM: TDX: Initialize TDX module when loading kvm_intel.ko

[Xiaoyao Li]

On 5/6/2022 2:14 AM, isaku.yamahata@xxxxxxxxx wrote:
> +int __init tdx_module_setup(void)
> +{
> +	const struct tdsysinfo_struct *tdsysinfo;
> +	int ret = 0;
> +
> +	BUILD_BUG_ON(sizeof(*tdsysinfo) != 1024);
> +	BUILD_BUG_ON(TDX_MAX_NR_CPUID_CONFIGS != 37);
> +
> +	ret = tdx_detect();
> +	if (ret) {
> +		pr_info("Failed to detect TDX module.\n");
> +		return ret;
> +	}
> +
> +	ret = tdx_init();
> +	if (ret) {
> +		pr_info("Failed to initialize TDX module.\n");
> +		return ret;
> +	}
> +
> +	tdsysinfo = tdx_get_sysinfo();
> +	if (tdx_caps.nr_cpuid_configs > TDX_MAX_NR_CPUID_CONFIGS)
> +		return -EIO;

It needs to check tdsysinfo->num_cpuid_config against 
TDX_MAX_NR_CPUID_CONFIG

or move the check down after tdx_caps is initialized.

> +	tdx_caps = (struct tdx_capabilities) {
> +		.tdcs_nr_pages = tdsysinfo->tdcs_base_size / PAGE_SIZE,
> +		/*
> +		 * TDVPS = TDVPR(4K page) + TDVPX(multiple 4K pages).
> +		 * -1 for TDVPR.
> +		 */
> +		.tdvpx_nr_pages = tdsysinfo->tdvps_base_size / PAGE_SIZE - 1,
> +		.attrs_fixed0 = tdsysinfo->attributes_fixed0,
> +		.attrs_fixed1 = tdsysinfo->attributes_fixed1,
> +		.xfam_fixed0 =	tdsysinfo->xfam_fixed0,
> +		.xfam_fixed1 = tdsysinfo->xfam_fixed1,
> +		.nr_cpuid_configs = tdsysinfo->num_cpuid_config,
> +	};
> +	if (!memcpy(tdx_caps.cpuid_configs, tdsysinfo->cpuid_configs,
> +			tdsysinfo->num_cpuid_config *
> +			sizeof(struct tdx_cpuid_config)))
> +		return -EIO;
> +
> +	return 0;
> +}