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Date:   Tue, 27 Aug 2019 18:11:06 +0100
From:   Matthew Garrett <mjg59@srcf.ucam.org>
To:     Seunghun Han <kkamagui@gmail.com>
Cc:     Matthew Garrett <mjg59@google.com>,
        Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        Peter Huewe <peterhuewe@gmx.de>,
        "open list:TPM DEVICE DRIVER" <linux-integrity@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86: tpm: Remove a busy bit of the NVS area for
 supporting AMD's fTPM
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On Wed, Aug 28, 2019 at 01:36:30AM +0900, Seunghun Han wrote:

> I got your point. Is there any problem if some regions which don't
> need to be handled in NVS area are saved and restored? If there is a
> problem, how about adding code for ignoring the regions in NVS area to
> the nvs.c file like Jarkko said? If we add the code, we can save and
> restore NVS area without driver's interaction.

The only thing that knows which regions should be skipped by the NVS 
driver is the hardware specific driver, so the TPM driver needs to ask 
the NVS driver to ignore that region and grant control to the TPM 
driver.

-- 
Matthew Garrett | mjg59@srcf.ucam.org