Re: [PATCH] firmware: qcom: qcm: fix unused qcom_scm_qseecom_allowlist

[Maximilian Luz]

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@xxxxxxxxx>
> > > Closes: https://lore.kernel.org/oe-kbuild-all/202311191654.S4wlVUrz-lkp@xxxxxxxxx/
> > > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> > > ---
> > >    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