Re: [PATCH v3] Makefile: use -z pack-relative-relocs

[Masahiro Yamada]

On Thu, Apr 13, 2023 at 11:55 PM Will Deacon <will@xxxxxxxxxx> wrote:
>
> On Tue, Apr 11, 2023 at 08:09:44PM +0000, Fangrui Song wrote:
> > Commit 27f2a4db76e8 ("Makefile: fix GDB warning with CONFIG_RELR")
> > added --use-android-relr-tags to fix a GDB warning
> >
> > BFD: /android0/linux-next/vmlinux: unknown type [0x13] section `.relr.dyn'
> >
> > The GDB warning has been fixed in version 11.2.
> >
> > The DT_ANDROID_RELR tag was deprecated since DT_RELR was standardized.
> > Thus, --use-android-relr-tags should be removed. While making the
> > change, try -z pack-relative-relocs, which is supported since LLD 15.
> > Keep supporting --pack-dyn-relocs=relr as well for older LLD versions.
> > There is no indication of obsolescence for --pack-dyn-relocs=relr.
> >
> > As of today, GNU ld supports the latter option for x86 and powerpc64
> > ports and has no intention to support --pack-dyn-relocs=relr. In the
> > absence of the glibc symbol version GLIBC_ABI_DT_RELR,
> > --pack-dyn-relocs=relr and -z pack-relative-relocs are identical in
> > ld.lld.
> >
> > GNU ld and newer versions of LLD report warnings (instead of errors) for
> > unknown -z options. Only errors lead to non-zero exit codes. Therefore,
> > we should test --pack-dyn-relocs=relr before testing
> > -z pack-relative-relocs.
> >
> > Link: https://github.com/ClangBuiltLinux/linux/issues/1057
> > Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=a619b58721f0a03fd91c27670d3e4c2fb0d88f1e
> > Signed-off-by: Fangrui Song <maskray@xxxxxxxxxx>
> > Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> > ---
> >  Makefile                      | 3 ++-
> >  scripts/tools-support-relr.sh | 8 ++++++--
> >  2 files changed, 8 insertions(+), 3 deletions(-)
>
> Acked-by: Will Deacon <will@xxxxxxxxxx>
>
> Masahiro -- are you happy to pick this one up?


Sure. Applied to linux-kbuild.


(I will push it next week.)


> If not, I can take it via
> arm64 (as the only arch currently using this reloc format).
>
> Cheers,
>
> Will



-- 
Best Regards
Masahiro Yamada