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Message-ID: <8ee13525-74d1-4308-b7b5-c01daa5352e2@gmail.com>
Date:   Tue, 21 Nov 2023 11:54:34 +0100
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Subject: Re: [PATCH] firmware: qcom: qcm: fix unused
 qcom_scm_qseecom_allowlist
To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Johan Hovold <johan+linaro@kernel.org>,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     kernel test robot <lkp@intel.com>
References: <20231120185623.338608-1-krzysztof.kozlowski@linaro.org>
 <2f14aab8-a5bb-4af4-9475-afe6b678a7fd@gmail.com>
 <e7565064-42a4-43fd-82f7-2e84066bee55@linaro.org>
From:   Maximilian Luz <luzmaximilian@gmail.com>
In-Reply-To: <e7565064-42a4-43fd-82f7-2e84066bee55@linaro.org>
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Am 11/21/2023 um 8:07 AM schrieb Krzysztof Kozlowski:
> On 20/11/2023 20:56, Maximilian Luz wrote:
>> On 11/20/23 19:56, Krzysztof Kozlowski wrote:
>>> For !OF builds, the qcom_scm_qseecom_allowlist is unused:
>>>
>>>     drivers/firmware/qcom/qcom_scm.c:1652:34: error: ‘qcom_scm_qseecom_allowlist’ defined but not used [-Werror=unused-const-variable=]
>>>
>>> Fixes: 00b1248606ba ("firmware: qcom_scm: Add support for Qualcomm Secure Execution Environment SCM interface")
>>> Reported-by: kernel test robot <lkp@intel.com>
>>> Closes: https://lore.kernel.org/oe-kbuild-all/202311191654.S4wlVUrz-lkp@intel.com/
>>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>> ---
>>>    drivers/firmware/qcom/qcom_scm.c | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
>>> index 520de9b5633a..ecdb367dc9b8 100644
>>> --- a/drivers/firmware/qcom/qcom_scm.c
>>> +++ b/drivers/firmware/qcom/qcom_scm.c
>>> @@ -1649,7 +1649,7 @@ EXPORT_SYMBOL_GPL(qcom_scm_qseecom_app_send);
>>>     * We do not yet support re-entrant calls via the qseecom interface. To prevent
>>>     + any potential issues with this, only allow validated machines for now.
>>>     */
>>> -static const struct of_device_id qcom_scm_qseecom_allowlist[] = {
>>> +static const struct of_device_id qcom_scm_qseecom_allowlist[] __maybe_unused = {
>>>    	{ .compatible = "lenovo,thinkpad-x13s", },
>>>    	{ }
>>>    };
>>
>> Thanks! Given that we're right now only allowing qseecom clients to load
>> on devices within that list, maybe it would be cleaner to make
>> QCOM_QSEECOM depend on OF explicitly instead?
> 
> There is no code dependency here.

Which is why I'm fine with this as well. It would just drop
currently unused code on !OF configs.

> The driver should already depend on
> ARCH_QCOM which select OF. Are you saying it does not depend on
> ARCH_QCOM? Why?

QCOM_QSEECOM depends only on QCOM_SCM. QCOM_SCM does not have
any dependencies. Instead, it is selected by ARCH_QCOM.

Best regards,
Max