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Date: Mon, 29 Nov 2021 10:50:18 +0100
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: Andrew Fish <afish@apple.com>
Cc: edk2-devel-groups-io <devel@edk2.groups.io>, maobibo@loongson.cn
Subject: Re: [edk2-devel] one possible issue with ovmf fvb
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  Hi,

> On real X64 hardware you can’t be in 64-bit mode without pageables,
> and you can’t put pageables in the ROM. Thus PEI ends up being IA32
> (i386) and this usually means the DXE Core gets loaded < 4 GiB, and
> the initial memory map for DXE is memory < 4 GiB.

Well, to exact there are two variants, one with PEI being IA32
(OvmfPkgIa32X64.dsc) and the other with PEI being X64 (OvmfPkgX64.dsc).
The latter does page table setup and switch to long mode in ResetVector
code.

But, yes, on both cases the firmware volume with PEI+DXE ends up being
loaded below 4 GiB.

take care,
  Gerd