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Date: Sun, 25 Feb 2024 06:23:13 -0500
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Subject: Re: [PATCH 1/3] tpm: protect against locality counter underflow
To: Jarkko Sakkinen <jarkko@kernel.org>,
 Lino Sanfilippo <l.sanfilippo@kunbus.com>,
 Alexander Steffen <Alexander.Steffen@infineon.com>,
 Jason Gunthorpe <jgg@ziepe.ca>, Sasha Levin <sashal@kernel.org>,
 linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Ross Philipson <ross.philipson@oracle.com>,
 Kanth Ghatraju <kanth.ghatraju@oracle.com>, Peter Huewe <peterhuewe@gmx.de>
References: <20240131170824.6183-1-dpsmith@apertussolutions.com>
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 <ae3fecc4-7b76-4607-8749-045e17941923@infineon.com>
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From: "Daniel P. Smith" <dpsmith@apertussolutions.com>
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On 2/23/24 07:58, Jarkko Sakkinen wrote:
> On Fri Feb 23, 2024 at 3:58 AM EET, Daniel P. Smith wrote:
>>> Just adding here that I wish we also had a log transcript of bug, which
>>> is right now missing. The explanation believable enough to move forward
>>> but I still wish to see a log transcript.
>>
>> That will be forth coming.
> 
> I did not respond yet to other responses that you've given in the past
> 12'ish hours or so (just woke up) but I started to think how all this
> great and useful information would be best kept in memory. Some of it
> has been discussed in the past but there is lot of small details that
> are too easily forgotten.
> 
> I'd think the best "documentation" approach here would be inject the
> spec references to the sites where locality behaviour is changed so
> that it is easy in future cross-reference them, and least of risk
> of having code changes that would break anything. I think this way
> all the information that you provided is best preserved for the
> future.
> 
> Thanks a lot for great and informative responses!

No problem at all.

Here is a serial output[1] from a dynamic launch using Linux Secure 
Launch v7[2] with one additional patch[3] to dump TPM driver state.

[1] https://paste.debian.net/1308538/
[2] 
https://lore.kernel.org/lkml/scpu273f2mprr2uvjlyk2xrjjtcduhse2eb45lmj7givn6jh4u@i2v4f2vbldu4/T/
[3] https://paste.debian.net/1308539/