Re: [PATCH RFC v2 1/2] binfmt_elf: Wire up AT_HWCAP3 at AT_HWCAP4

Anshuman Khandual
2024-10-08T07:06:42Z

On 10/5/24 01:56, Mark Brown wrote:
> AT_HWCAP3 and AT_HWCAP4 were recently defined for use on PowerPC in commit
> 3281366a8e79 ("uapi/auxvec: Define AT_HWCAP3 and AT_HWCAP4 aux vector,
> entries"). Since we want to start using AT_HWCAP3 on arm64 add support for
> exposing both these new hwcaps via binfmt_elf.
>
> Signed-off-by: Mark Brown <broonie@kernel.org>
> ---
> fs/binfmt_elf.c | 6 ++++++
> fs/binfmt_elf_fdpic.c | 6 ++++++
> fs/compat_binfmt_elf.c | 10 ++++++++++
> 3 files changed, 22 insertions(+)
>
> diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
> index 06dc4a57ba78a7939bbde96bf181eefa950ea13a..3039a6b7aba4bd38f26e21b626b579cc03f3a03e 100644
> --- a/fs/binfmt_elf.c
> +++ b/fs/binfmt_elf.c
> @@ -257,6 +257,12 @@ create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec,
> NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
> #ifdef ELF_HWCAP2
> NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
> +#endif
> +#ifdef ELF_HWCAP3
> + NEW_AUX_ENT(AT_HWCAP3, ELF_HWCAP3);
> +#endif
> +#ifdef ELF_HWCAP4
> + NEW_AUX_ENT(AT_HWCAP4, ELF_HWCAP4);
> #endif
> NEW_AUX_ENT(AT_EXECFN, bprm->exec);
> if (k_platform) {
> diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
> index 4fe5bb9f1b1f5e0be6e8d1ef5b20492935b90633..31d253bd3961a8679678c600f4346bba23502598 100644
> --- a/fs/binfmt_elf_fdpic.c
> +++ b/fs/binfmt_elf_fdpic.c
> @@ -623,6 +623,12 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
> NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
> #ifdef ELF_HWCAP2
> NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
> +#endif
> +#ifdef ELF_HWCAP3
> + NEW_AUX_ENT(AT_HWCAP3, ELF_HWCAP3);
> +#endif
> +#ifdef ELF_HWCAP4
> + NEW_AUX_ENT(AT_HWCAP4, ELF_HWCAP4);
> #endif
> NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE);
> NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
> diff --git a/fs/compat_binfmt_elf.c b/fs/compat_binfmt_elf.c
> index 8f0af4f626316ed2e92204ff9bf381cd14103ae9..d5ef5469e4e620f6ee97f40ce9cbbfa48e37e33c 100644
> --- a/fs/compat_binfmt_elf.c
> +++ b/fs/compat_binfmt_elf.c
> @@ -80,6 +80,16 @@
> #define ELF_HWCAP2 COMPAT_ELF_HWCAP2
> #endif
>
> +#ifdef COMPAT_ELF_HWCAP3
> +#undef ELF_HWCAP3
> +#define ELF_HWCAP3 COMPAT_ELF_HWCAP3
> +#endif
> +
> +#ifdef COMPAT_ELF_HWCAP4
> +#undef ELF_HWCAP4
> +#define ELF_HWCAP4 COMPAT_ELF_HWCAP4
> +#endif
> +
> #ifdef COMPAT_ARCH_DLINFO
> #undef ARCH_DLINFO
> #define ARCH_DLINFO COMPAT_ARCH_DLINFO
>

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>