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Date: Sun, 16 Sep 2018 22:16:05 +0300
From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Martin Galvan <omgalvan.86@gmail.com>
Cc: linux-integrity@vger.kernel.org
Subject: Re: Question about the TPM driver
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On Thu, Sep 13, 2018 at 10:14:30AM -0300, Martin Galvan wrote:
> Hi all,
> 
> I noticed that, after a command is done, the TPM driver only allows
> for a single read operation (for a limited time). If I wanted to e.g.
> check a command's response code before attempting to read the rest of
> the response, my next read would fail. Same happens if I take too long
> to read a command's results.
> 
> I can understand the timeout, but I'm curious about this single-read
> policy, especially since some commands such as GetCapability don't
> guarantee how much data will actually be returned. Does anyone know
> why it was implemented this way?
> 
> Thanks

I understand your concerns but without a concrete workload there is no
problem with this behavior.

/Jarkko