Re: [PATCH v3 0/2] Fix lack of section mismatch warnings with LTO

Masahiro Yamada
2022-12-14T06:53:00Z

On Wed, Dec 14, 2022 at 3:35 AM Nathan Chancellor <nathan@kernel.org> wrote:
>
> Hi all,
>
> Vincent recently reported an issue with lack of section mismatch
> warnings with LTO. This is due to commit 6c730bfc894f ("modpost: handle
> -ffunction-sections"), which ignores all function sections for modpost.
>
> I believe this is incorrect, as these function sections may still refer
> to symbols in other sections and they will ultimately be coalesced into
> .text by vmlinux.lds anyways.
>
> The first patch fixes a warning that I see with allmodconfig + ThinLTO
> builds after applying the second patch. The second patch moves ".text.*"
> into TEXT_SECTIONS so that modpost audits them for mismatches.
>
> I expect this to go via the kbuild tree with an ack from the padata
> maintainers.

Daniel Acked v2.

Applied to kbuild with his Acked-by.

Thanks.

>
> Cc: Steffen Klassert <steffen.klassert@secunet.com>
> Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
> Cc: linux-crypto@vger.kernel.org
>
> v3:
> - Stick a comment above padata_work_init() to explain presence of
> __ref (Masahiro, Daniel).
> - Expand on problem in first patch's commit message (Masahiro).
> - Adjust location of __ref within function definition (Daniel)
> - Fix typo in commit message of second patch (Masahiro).
> v2: https://lore.kernel.org/20221207191657.2852229-1-nathan@kernel.org/
> v1: https://lore.kernel.org/20221129190123.872394-1-nathan@kernel.org/
>
> Nathan Chancellor (2):
> padata: Mark padata_work_init() as __ref
> modpost: Include '.text.*' in TEXT_SECTIONS
>
> kernel/padata.c | 12 ++++++++++--
> scripts/mod/modpost.c | 4 ++--
> 2 files changed, 12 insertions(+), 4 deletions(-)
>
>
> base-commit: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476
> --
> 2.39.0
>

--
Best Regards
Masahiro Yamada