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Subject: Re: [PATCH] tpm: Revert "tpm: fix invalid locking in NONBLOCKING
 mode"
To:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc:     James Bottomley <James.Bottomley@HansenPartnership.com>,
        Mario Limonciello <mario.limonciello@dell.com>,
        Peter Huewe <peterhuewe@gmx.de>,
        Jason Gunthorpe <jgg@ziepe.ca>, Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jeffrin Jose T <jeffrin@rajagiritech.edu.in>,
        Alex Guzman <alex@guzman.io>
References: <20200526183213.20720-1-mario.limonciello@dell.com>
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 <f63afdc1-6c40-dc0d-bb9a-154bc51d3b95@gmail.com>
 <20200528003040.GA4781@linux.intel.com>
From:   Tadeusz Struk <tstruk@gmail.com>
Message-ID: <e939739d-d193-95e8-c142-4efa57be2502@gmail.com>
Date:   Wed, 27 May 2020 21:40:25 -0700
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On 5/27/20 5:30 PM, Jarkko Sakkinen wrote:
>> This won't help if the message is read by an async tcti. If the problem lies
>> in the chip get locality code, perhaps this could help to debug the root-cause
>> instead of masking it out in the upper layer code:
> What is TCTI and async TCTI? Not following.

TPM Command Transmission Interface (TCTI) as defined by TCG in
https://trustedcomputinggroup.org/resource/tss-tcti-specification/

the reason we added the O_NONBLOCK mode was to satisfy the TCG spec for async TCTI.

Thanks,
Tadeusz