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From:   Jens Wiklander <jens.wiklander@linaro.org>
Date:   Mon, 12 Apr 2021 09:36:53 +0200
Message-ID: <CAHUa44Gga=k3indU8FC3X5xE=6RnKEDNeZBDWeJzm47-Spm0QA@mail.gmail.com>
Subject: Re: [PATCH v2] tee: amdtee: unload TA only when its refcount becomes 0
To:     Rijo Thomas <Rijo-john.Thomas@amd.com>
Cc:     Dan Carpenter <dan.carpenter@oracle.com>,
        Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>,
        Mythri Pandeshwara krishna <mythri.pandeshwarakrishna@amd.com>,
        OP-TEE TrustedFirmware <op-tee@lists.trustedfirmware.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Mon, Apr 5, 2021 at 11:43 AM Rijo Thomas <Rijo-john.Thomas@amd.com> wrote:
>
> Same Trusted Application (TA) can be loaded in multiple TEE contexts.
>
> If it is a single instance TA, the TA should not get unloaded from AMD
> Secure Processor, while it is still in use in another TEE context.
>
> Therefore reference count TA and unload it when the count becomes zero.
>
> Fixes: 757cc3e9ff1d ("tee: add AMD-TEE driver")
> Reviewed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
> Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
> ---
> v2:
>  * Unload TA if get_ta_refcount() fails
>
>  drivers/tee/amdtee/amdtee_private.h | 13 ++++
>  drivers/tee/amdtee/call.c           | 94 ++++++++++++++++++++++++++---
>  drivers/tee/amdtee/core.c           | 15 +++--
>  3 files changed, 106 insertions(+), 16 deletions(-)

Looks good to me. Please address Dan's comment.

Cheers,
Jens