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Message-ID: <7bd30975-fdcc-7d87-af4a-448b92bb6e02@linux.intel.com>
Date:   Tue, 2 Aug 2022 10:01:10 +0800
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Subject: Re: [PATCH v5 1/22] x86/virt/tdx: Detect TDX during kernel boot
To:     Kai Huang <kai.huang@intel.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     seanjc@google.com, pbonzini@redhat.com, dave.hansen@intel.com,
        len.brown@intel.com, tony.luck@intel.com,
        rafael.j.wysocki@intel.com, reinette.chatre@intel.com,
        dan.j.williams@intel.com, peterz@infradead.org, ak@linux.intel.com,
        kirill.shutemov@linux.intel.com,
        sathyanarayanan.kuppuswamy@linux.intel.com,
        isaku.yamahata@intel.com
References: <cover.1655894131.git.kai.huang@intel.com>
 <062075b36150b119bf2d0a1262de973b0a2b11a7.1655894131.git.kai.huang@intel.com>
From:   "Wu, Binbin" <binbin.wu@linux.intel.com>
In-Reply-To: <062075b36150b119bf2d0a1262de973b0a2b11a7.1655894131.git.kai.huang@intel.com>
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On 2022/6/22 19:15, Kai Huang wrote:
> +	/*
> +	 * TDX guarantees at least two TDX KeyIDs are configured by
> +	 * BIOS, otherwise SEAMRR is disabled.  Invalid TDX private
> +	 * range means kernel bug (TDX is broken).
> +	 */
> +	if (WARN_ON(!tdx_keyid_start || tdx_keyid_num < 2)) {
Do you think it's better to define a meaningful macro instead of the 
number here and below?
> +		tdx_keyid_start = tdx_keyid_num = 0;
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +

> +
> +/**
> + * platform_tdx_enabled() - Return whether BIOS has enabled TDX
> + *
> + * Return whether BIOS has enabled TDX regardless whether the TDX module
> + * has been loaded or not.
> + */
> +bool platform_tdx_enabled(void)
> +{
> +	return tdx_keyid_num >= 2;
> +}
>
>