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Date: Thu, 14 Oct 2021 10:58:51 +0200
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: devel@edk2.groups.io, James Bottomley <jejb@linux.ibm.com>,
	Min Xu <min.m.xu@intel.com>, Jiewen Yao <jiewen.yao@intel.com>,
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	Ard Biesheuvel <ardb+tianocore@kernel.org>,
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	Michael Roth <Michael.Roth@amd.com>
Subject: Re: [PATCH v9 30/32] OvmfPkg/PlatformPei: mark cpuid and secrets memory reserved in EFI map
Message-ID: <20211014085851.e5xtspfcyz75lgog@sirius.home.kraxel.org>
References: <20211013165713.727815-1-brijesh.singh@amd.com>
 <20211013165713.727815-31-brijesh.singh@amd.com>
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On Wed, Oct 13, 2021 at 11:57:11AM -0500, Brijesh Singh wrote:
> When SEV-SNP is active, the CPUID and Secrets memory range contains the
> information that is used during the VM boot. The content need to be persist
> across the kexec boot. Mark the memory range as Reserved in the EFI map
> so that guest OS or firmware does not use the range as a system RAM.

Why is this needed?  Isn't the complete firmware memory tagged as
reserved anyway?

take care,
  Gerd