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Date: Fri, 16 Sep 2016 09:11:47 +0200
From: Borislav Petkov <bp@alien8.de>
To: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-arch@vger.kernel.org, linux-efi@vger.kernel.org,
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Subject: Re: [RFC PATCH v2 19/20] x86: Access the setup data through debugfs
 un-encrypted
Message-ID: <20160916071147.GB23229@nazgul.tnic>
References: <20160822223529.29880.50884.stgit@tlendack-t1.amdoffice.net>
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 <4a357b9b-7d53-5bd6-81db-9d8cc63a6c72@amd.com>
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On Thu, Sep 15, 2016 at 12:08:04PM -0500, Tom Lendacky wrote:
> The problem is that this physical address does not contain the
> encryption bit, and even if it did, it wouldn't matter.  The __va()
> define creates a virtual address that will be mapped as encrypted given
> the current approach (which is how I found this).  It's only ioremap()
> that would create a mapping without the encryption attribute and since
> this is unencrypted data it needs to be access accordingly.

I see. So since this is not obvious, please add this explanation to maybe

Documentation/x86/amd-memory-encryption.txt

and point in there to an example or so so.

Thanks.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
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