CONFIG_LD_DEAD_CODE_DATA_ELIMINATION: Section mismatch in reference from the variable via_pmu_driver to the function .init.text:pmu_init()

[Mathieu Malaterre]

On Tue, Jul 3, 2018 at 11:40 AM Mathieu Malaterre <malat at debian.org> wrote:
>
> Hi Nick,
>
> Would you consider this a bug:
>
> $ touch drivers/macintosh/via-pmu.c
> $ CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=n make ARCH=powerpc
> CROSS_COMPILE=powerpc-linux-gnu-
> ...
>   LD      vmlinux.o
>   MODPOST vmlinux.o
> WARNING: vmlinux.o(.data+0x216018): Section mismatch in reference from
> the variable via_pmu_driver to the function .init.text:pmu_init()
> The variable via_pmu_driver references
> the function __init pmu_init()
> If the reference is valid then annotate the
> variable with __init* or __refdata (see linux/init.h) or name the variable:
> *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
>
> While:
>
> $ touch drivers/macintosh/via-pmu.c
> $ CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y make ARCH=powerpc
> CROSS_COMPILE=powerpc-linux-gnu-
> ...
>   AR      init/built-in.a
>   AR      built-in.a
>   LD      vmlinux.o
>   MODPOST vmlinux.o
>   KSYM    .tmp_kallsyms1.o
>   KSYM    .tmp_kallsyms2.o
>   LD      vmlinux
>   SORTEX  vmlinux
>   SYSMAP  System.map
> ...
>
> Thanks for comment

Just to clarify I reverted 58935176ad17976b7a7f6ea25c0ceb2ca4308a30
just as to reproduce a warning. So my question (rephrased):

Is this expected that CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y inhibit
the behavior of  CONFIG_DEBUG_SECTION_MISMATCH=y ?

Thanks