Re: [RFC PATCH v2 19/20] x86: Access the setup data through debugfs un-encrypted

From: Borislav Petkov
Date: Fri Sep 16 2016 - 03:12:26 EST


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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