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Date:   Fri, 11 Aug 2023 11:39:52 +0100
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Subject: Re: [PATCH v2 3/4] venus: hfi: add checks to handle capabilities from
 firmware
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To:     Vikash Garodia <quic_vgarodia@quicinc.com>,
        stanimir.k.varbanov@gmail.com, agross@kernel.org,
        andersson@kernel.org, konrad.dybcio@linaro.org, mchehab@kernel.org,
        hans.verkuil@cisco.com, tfiga@chromium.org
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        linux-kernel@vger.kernel.org, stable@vger.kernel.org
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From:   Bryan O'Donoghue <bryan.odonoghue@linaro.org>
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On 11/08/2023 09:51, Vikash Garodia wrote:
> 
> On 8/11/2023 2:11 PM, Bryan O'Donoghue wrote:
>> On 11/08/2023 06:54, Vikash Garodia wrote:
>>> The case is all about rogue firmware. If there is a need to fill the same cap
>>> again, that itself indicates that the payload from firmware is not correct. In
>>> such cases, the old as well as new cap data are not reliable. Though the
>>> authenticity of the data cannot be ensured, the check would avoid any OOB during
>>> such rogue firmware case.
>>
>> Then why favour the old cap report over the new ?
> 
> When the driver hits the case for OOB, thats when it knows that something has
> gone wrong. Keeping old or new, both are invalid values in such case, nothing to
> favor any value.
> 
> Regards,
> Vikash

Is this hypothetical or a real bug you are actually working to mitigate ?

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bod