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Date:   Mon, 28 Nov 2022 14:19:50 -0800
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Subject: Re: [PATCH v7 11/20] x86/virt/tdx: Add placeholder to construct TDMRs
 to cover all TDX memory regions
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To:     "Huang, Kai" <kai.huang@intel.com>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc:     "Luck, Tony" <tony.luck@intel.com>,
        "bagasdotme@gmail.com" <bagasdotme@gmail.com>,
        "ak@linux.intel.com" <ak@linux.intel.com>,
        "Wysocki, Rafael J" <rafael.j.wysocki@intel.com>,
        "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>,
        "Christopherson,, Sean" <seanjc@google.com>,
        "Chatre, Reinette" <reinette.chatre@intel.com>,
        "pbonzini@redhat.com" <pbonzini@redhat.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "Yamahata, Isaku" <isaku.yamahata@intel.com>,
        "Shahar, Sagi" <sagis@google.com>,
        "imammedo@redhat.com" <imammedo@redhat.com>,
        "Gao, Chao" <chao.gao@intel.com>,
        "Brown, Len" <len.brown@intel.com>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "sathyanarayanan.kuppuswamy@linux.intel.com" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        "Huang, Ying" <ying.huang@intel.com>,
        "Williams, Dan J" <dan.j.williams@intel.com>
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From:   Dave Hansen <dave.hansen@intel.com>
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On 11/28/22 14:13, Huang, Kai wrote:
> Apologize I am not entirely sure whether I fully got your point.  Do you mean
> something like below?
...

No, something like this:

static int init_tdx_module(void)
{
	static struct tdsysinfo_struct tdx_sysinfo; /* too rotund for the stack */
        ...
        tdx_get_sysinfo(&tdx_sysinfo, ...);
        ...

But, also, seriously, 3k on the stack is *fine* if you can shut up the
warnings.  This isn't going to be a deep call stack to begin with.