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Date: Mon, 22 May 2023 13:18:59 +0200
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: devel@edk2.groups.io, Jordan Justen <jordan.l.justen@intel.com>, 
	Oliver Steffen <osteffen@redhat.com>, Pawel Polawski <ppolawsk@redhat.com>, 
	Ard Biesheuvel <ardb+tianocore@kernel.org>, Jiewen Yao <jiewen.yao@intel.com>
Subject: Re: [PATCH 1/3] OvmfPkg/PlatformInitLib: check PcdUse1GPageTable
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On Mon, May 22, 2023 at 12:37:51PM +0200, Ard Biesheuvel wrote:
> On Wed, 17 May 2023 at 12:24, Gerd Hoffmann <kraxel@redhat.com> wrote:
> >
> > If PcdUse1GPageTable is not enabled restrict the physical address space
> > used to 1TB, to limit the amount of memory needed for identity mapping
> > page tables.
> >
> > The same already happens in case the processor has no support for
> > gigabyte pages.
> >
> 
> Apologies for the noob question, but does this mean EDK2 maps the
> entire address space 1:1, not just the region that as any DRAM in it?

I just saw memory usage and boot time go up.  Didn't check whenever that
was just the 64-bit mmio area (which recent ovmf scales up with the
available address space) or all address space.

take care,
  Gerd