Message-ID: <640dd9a5bdb4c28b7429a6ab9507d645de06c125.camel@kernel.org>
Subject: Re: [PATCH v19 2/5] tpm: tpm_tis: Rewrite "tpm_tis_req_canceled()"
From:   Jarkko Sakkinen <jarkko@kernel.org>
To:     amirmizi6@gmail.com, Eyal.Cohen@nuvoton.com,
        oshrialkoby85@gmail.com, alexander.steffen@infineon.com,
        robh+dt@kernel.org, mark.rutland@arm.com, peterhuewe@gmx.de,
        jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org,
        benoit.houyere@st.com, eajames@linux.ibm.com, joel@jms.id.au
Cc:     devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com,
        tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com,
        Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com,
        shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com
Date:   Wed, 17 Nov 2021 10:03:58 +0200
In-Reply-To: <20211104140211.6258-3-amirmizi6@gmail.com>
References: <20211104140211.6258-1-amirmizi6@gmail.com>
         <20211104140211.6258-3-amirmizi6@gmail.com>
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On Thu, 2021-11-04 at 16:02 +0200, amirmizi6@gmail.com wrote:
> From: Amir Mizinski <amirmizi6@gmail.com>
>=20
> tpm_tis_req_canceled() function is used to check if the caller requested
> to abort the current operation. It was found that in some cases
> tpm_tis_req_canceled() wrongly returned true.

Please, bring some context, i.e. please describe the scenarios.

> Since a cancel request sets the TPM_STS.commandReady field to TRUE, the=
=20
          ~~~~~~~~~~~~~~

What the heck is this? Please refer the exact things.


> tpm_tis_req_canceled() function should check only the TPM_STS.commandRead=
y
> field value.

Why?

> The case for TPM_VID_WINBOND is wrong and was therefore removed.

Why?

It is not removed in the existing mainline, so it definitely *was not*
removed.

> Also, the default comparison is wrong. Only cmdReady bit needs to be
> compared instead of the full lower status register byte.

You should split this into two patches, if it fixes two different
issues.

/Jarkko