Re: [PATCH 1/2] padata: Do not mark padata_mt_helper() as __init

From: Masahiro Yamada
Date: Wed Nov 30 2022 - 17:24:44 EST


On Wed, Nov 30, 2022 at 4:02 AM Nathan Chancellor <nathan@xxxxxxxxxx> wrote:
>
> When building arm64 allmodconfig + ThinLTO with clang and a proposed
> modpost update to account for -ffuncton-sections, the following warning
> appears:



How to enable -ffuncton-sections for ARCH=arm64 ?
(in other words, how to set CONFIG_LD_DEAD_CODE_DATA_ELIMINATION ?)

In upstream, it is only possible for mips and powerpc.

./arch/mips/Kconfig:82: select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
./arch/powerpc/Kconfig:237: select HAVE_LD_DEAD_CODE_DATA_ELIMINATION



Is there another proposal to add it for arm64,
or is this about a downstream kernel?





>
> WARNING: modpost: vmlinux.o: section mismatch in reference: padata_work_init (section: .text.padata_work_init) -> padata_mt_helper (section: .init.text)
> WARNING: modpost: vmlinux.o: section mismatch in reference: padata_work_init (section: .text.padata_work_init) -> padata_mt_helper (section: .init.text)
>
> In both cases, an __init function calls padata_work_init(), which is not
> marked __init, with padata_mt_helper(), another __init function, as a
> work function argument.
>
> padata_work_init() is called from non-init paths, otherwise it could be
> marked __init to resolve the warning. Instead, remove __init from
> padata_mt_helper() to resolve the warning.
>
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> ---
> Cc: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
> Cc: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>
> Cc: linux-crypto@xxxxxxxxxxxxxxx
> ---
> kernel/padata.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/padata.c b/kernel/padata.c
> index e5819bb8bd1d..c2271d7e446d 100644
> --- a/kernel/padata.c
> +++ b/kernel/padata.c
> @@ -45,7 +45,7 @@ struct padata_mt_job_state {
> };
>
> static void padata_free_pd(struct parallel_data *pd);
> -static void __init padata_mt_helper(struct work_struct *work);
> +static void padata_mt_helper(struct work_struct *work);
>
> static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
> {
> @@ -425,7 +425,7 @@ static int padata_setup_cpumasks(struct padata_instance *pinst)
> return err;
> }
>
> -static void __init padata_mt_helper(struct work_struct *w)
> +static void padata_mt_helper(struct work_struct *w)
> {
> struct padata_work *pw = container_of(w, struct padata_work, pw_work);
> struct padata_mt_job_state *ps = pw->pw_data;
> --
> 2.38.1
>


--
Best Regards
Masahiro Yamada