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Subject: Re: [PATCH 1/2] optee: fix tee out of memory failure seen during
 kexec reboot
To:     Jens Wiklander <jens.wiklander@linaro.org>
Cc:     Dhananjay Phadke <dphadke@linux.microsoft.com>,
        allen.lkml@gmail.com, zajec5@gmail.com,
        linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
        op-tee@lists.trustedfirmware.org,
        linux-arm-kernel@lists.infradead.org,
        bcm-kernel-feedback-list@broadcom.com
References: <20210217092714.121297-2-allen.lkml@gmail.com>
 <20210217092714.121297-2-allen.lkml@gmail.com>
 <8d87655f-27c6-6a66-6eb0-9244279fbf2c@linux.microsoft.com>
 <20210223081948.GA1836717@jade>
From:   Allen Pais <apais@linux.microsoft.com>
Message-ID: <cbc963d5-6c4b-7e69-4a9b-3d66b95affab@linux.microsoft.com>
Date:   Tue, 23 Feb 2021 21:56:13 +0530
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>>>> -	/*
>>>> -	 * Ask OP-TEE to free all cached shared memory objects to decrease
>>>> -	 * reference counters and also avoid wild pointers in secure world
>>>> -	 * into the old shared memory range.
>>>> -	 */
>>>> -	optee_disable_shm_cache(optee);
>>>> +	if (shutdown) {
>>>> +		optee_disable_shm_cache(optee);
>>>> +	} else {
>>>> +		/*
>>>> +		 * Ask OP-TEE to free all cached shared memory
>>>> +		 * objects to decrease reference counters and
>>>> +		 * also avoid wild pointers in secure world
>>>> +		 * into the old shared memory range.
>>>> +		 */
>>>> +		optee_disable_shm_cache(optee);
>>> Calling optee_disable_shm_cache() in both if and else. It could be
>>> put in front of if().
>>>
>>
>>    Ideally, I could just use optee_remove for shutdown() too.
>> But it would not look good. Hence this approach.
> 
> What is the problem with using optee_remove() for shutdown()?
> 

  There is no problem, I just thought it would be more cleaner/readable
with this approach. If you'd like to keep it simple by just calling
optee_remove() for shutdown() too, I could quickly send out V2.

Thanks for the review.

- Allen