Re: [PATCH] firmware: qcom: scm: Hide QCOM_SCM instead of depending on ARCH_QCOM

[Geert Uytterhoeven]

Hi Sasha,

On Sun, 13 Sept 2026 at 19:30, Sasha Levin <sashal@xxxxxxxxxx> wrote:
> imx_v6_v7_defconfig fails to link:
>
>   arm-linux-gnueabihf-ld: drivers/firmware/qcom/qcom_scm.o: in function
>   `qcom_scm_pas_init_image':
>   qcom_scm.c:(.text+0xecc): undefined reference to `qcom_tzmem_alloc'
>   qcom_scm.c:(.text+0x2b0): undefined reference to `qcom_tzmem_free'
>   qcom_scm.c:(.text+0x1514): undefined reference to `qcom_tzmem_to_phys'
>
> QCOM_SCM gained a "depends on ARCH_QCOM || COMPILE_TEST", but it is
> selected from 20 places in the tree and several of those are reachable
> without ARCH_QCOM. DRM_MSM is one of them, via SOC_IMX5, which is how
> imx_v6_v7_defconfig ends up here:
>
>   WARNING: unmet direct dependencies detected for QCOM_SCM
>     Depends on [n]: ARCH_QCOM [=n] || COMPILE_TEST [=n]
>     Selected by [y]:
>     - DRM_MSM [=y] && ... && (ARCH_QCOM [=n] || SOC_IMX5 [=y] ||
>       COMPILE_TEST [=n]) && ...
>
> kconfig still honours the select and sets QCOM_SCM=y, but it does not
> propagate the selects of a symbol whose own dependencies are unmet, so
> QCOM_TZMEM is left unset, qcom_tzmem.c is not built, and the
> unconditional qcom_tzmem_*() calls in qcom_scm.c and qcom_scm-smc.c
> have nothing to bind to.
>
> The point of the dependency was only to stop asking the user about
> Qualcomm firmware interfaces when configuring a non-Qualcomm kernel.
> Express that as a prompt condition, which is what the same commit
> already did for QCOM_PAS: the symbol stays invisible, but it no longer
> carries a dependency that silently drops its selects.
>
> Found by KernelCI builds of the linus-next tree.

linux-next

>
> Fixes: 8fecd3194de3 ("firmware: QCOM interfaces should depend on ARCH_QCOM")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202609120634.g0HMAp3g-lkp@xxxxxxxxx/
> Assisted-by: LLM
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

Thanks for your patch!

> --- a/drivers/firmware/qcom/Kconfig
> +++ b/drivers/firmware/qcom/Kconfig
> @@ -26,8 +26,7 @@ config QCOM_PAS_TEE
>           by the firmware TEE implementation as the backend.
>
>  config QCOM_SCM
> -       tristate "Qualcomm PAS SCM interface driver"
> -       depends on ARCH_QCOM || COMPILE_TEST
> +       tristate "Qualcomm PAS SCM interface driver" if ARCH_QCOM || COMPILE_TEST
>         select QCOM_PAS
>         select QCOM_TZMEM
>         default y if ARCH_QCOM

LGTM for now, so
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

As the MSM driver is used on non-QCOM platforms, too, in the long run,
the "select QCOM_SCM" and "select QCOM_PAS" for DRM_MSM should probably
gain dependencies on ARCH_QCOM (like "select QCOM_UBWC_CONFIG if
ARCH_QCOM" already has), and the various qcom_*() should gain dummies.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds