Re: [PATCH] arm64: take SHN_LIVEPATCH syms into account when calculating plt_max_entries

[Miroslav Benes]

On Tue, 12 Jul 2016, Jessica Yu wrote:

> SHN_LIVEPATCH symbols are technically a subset of SHN_UNDEF/undefined
> symbols, except that their addresses are resolved by livepatch at runtime.
> Therefore, when calculating the upper-bound for the number of plt entries
> to allocate, make sure to take livepatch symbols into account as well.
> 
> Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>

FWIW, I think the patch does what we want, but it's for arm people to 
judge. It might be better to include it to Torsten's patch set.

Miroslav

> ---
> arch/arm64/kernel/module-plts.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kernel/module-plts.c b/arch/arm64/kernel/module-plts.c
> index 1ce90d8..1e95dc1 100644
> --- a/arch/arm64/kernel/module-plts.c
> +++ b/arch/arm64/kernel/module-plts.c
> @@ -122,7 +122,8 @@ static unsigned int count_plts(Elf64_Sym *syms, Elf64_Rela
> *rela, int num)
>                         * as well, so modules can never grow beyond that
> limit.
>                         */
>                        s = syms + ELF64_R_SYM(rela[i].r_info);
> -                       if (s->st_shndx != SHN_UNDEF)
> +                       if (s->st_shndx != SHN_UNDEF &&
> +                           s->st_shndx != SHN_LIVEPATCH)
>                                break;
> 
>                        /*
> -- 
> 2.5.5
>