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Message-ID: <7e63912a-895f-d3b3-3173-336beaa86d08@intel.com>
Date:   Thu, 28 Apr 2022 10:25:43 -0700
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Subject: Re: [PATCH v3 20/21] x86/virt/tdx: Add kernel command line to opt-in
 TDX host support
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To:     Kai Huang <kai.huang@intel.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     seanjc@google.com, pbonzini@redhat.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.1649219184.git.kai.huang@intel.com>
 <0d50d13e5f9bd590ee97ff150f1393c4d99a8fa0.1649219184.git.kai.huang@intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <0d50d13e5f9bd590ee97ff150f1393c4d99a8fa0.1649219184.git.kai.huang@intel.com>
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On 4/5/22 21:49, Kai Huang wrote:
> Enabling TDX consumes additional memory (used by TDX as metadata) and
> additional initialization time.  Introduce a kernel command line to
> allow to opt-in TDX host kernel support when user truly wants to use
> TDX.

From the cover letter:

	"This series doesn't initialize TDX at boot time"

Could you please square that circle for me?  How does a feature that
doesn't get initialized a boot time need a boot-time command line opt-in?