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Date: Fri, 15 Oct 2021 07:45:57 +0200
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: "Yao, Jiewen" <jiewen.yao@intel.com>
Cc: "devel@edk2.groups.io" <devel@edk2.groups.io>,
	"Xu, Min M" <min.m.xu@intel.com>,
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	Erdem Aktas <erdemaktas@google.com>,
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	Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: [edk2-devel] [PATCH V2 21/28] OvmfPkg: Update PlatformPei to support TDX
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  Hi,

> The original mailbox location is in low memory. If we do not relocate
> to high memory, then the OS will see a hole in low memory.

Well, both low and high memory to be exact.  qemu maps the whole
firmware image below 4G, and mirrors the topmost 128k (including
memfd + reset vector) below 1M.

Given that TDX starts the processor in 32bit mode, so it doesn't need
the 16bit entry @ f000:fff0, I assumed TDX completely ignores the low
memory mapping and uses only the high memory mapping.

So you are telling me this is not the case?

take care,
  Gerd