lkml.org 
[lkml]   [2021]   [Feb]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] kallsyms: fix nonconverging kallsyms table with lld
On Fri, Feb 5, 2021 at 12:30 AM Arnd Bergmann <arnd@kernel.org> wrote:
>
> From: Arnd Bergmann <arnd@arndb.de>
>
> ARM randconfig builds with lld sometimes show a build failure
> from kallsyms:
>
> Inconsistent kallsyms data
> Try make KALLSYMS_EXTRA_PASS=1 as a workaround
>
> The problem is the veneers/thunks getting added by the linker extend
> the symbol table, which in turn leads to more veneers being needed,
> so it may take a few extra iterations to converge.
>
> This bug has been fixed multiple times before, but comes back every time
> a new symbol name is used. lld uses a different set of idenitifiers from
> ld.bfd, so the additional ones need to be added as well.

Yes, this is a whack-a-mole.

I fixed the typo "idenitifiers" -> "identifiers"
and applied to linux-kbuild.

Thanks.




> I looked through the sources and found that arm64 and mips define similar
> prefixes, so I'm adding those as well, aside from the ones I observed. I'm
> not sure about powerpc64, which seems to already be handled through a
> section match, but if it comes back, the "__long_branch_" and "__plt_"
> prefixes would have to get added as well.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> scripts/kallsyms.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
> index 7ecd2ccba531..54ad86d13784 100644
> --- a/scripts/kallsyms.c
> +++ b/scripts/kallsyms.c
> @@ -112,6 +112,12 @@ static bool is_ignored_symbol(const char *name, char type)
> "__crc_", /* modversions */
> "__efistub_", /* arm64 EFI stub namespace */
> "__kvm_nvhe_", /* arm64 non-VHE KVM namespace */
> + "__AArch64ADRPThunk_", /* arm64 lld */
> + "__ARMV5PILongThunk_", /* arm lld */
> + "__ARMV7PILongThunk_",
> + "__ThumbV7PILongThunk_",
> + "__LA25Thunk_", /* mips lld */
> + "__microLA25Thunk_",
> NULL
> };
>
> --
> 2.29.2
>


--
Best Regards
Masahiro Yamada

\
 
 \ /
  Last update: 2021-02-05 09:45    [W:0.183 / U:0.716 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site