On Thu, Jun 22, 2023 at 12:54:30PM +0200, Christophe Leroy wrote:
> struct jump_entry {
> s32 code;
> s32 target;
> long key;
> };
>
> It means that the size of the third argument depends on
> whether we are building a 32 bits or 64 bits kernel.
>
> Therefore JUMP_ENTRY_SIZE must depend on elf_class_addrsize(elf).
>
> To allow that, entries[] table must be initialised at runtime. This is
> easily done by moving it into its only user which is special_get_alts().
>
> Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org>
However, it doesn't apply to tip/objtool/core because Josh went and
renamed a bunch of things including elf_class_addrsize(). It's now
elf_addr_siize().
> ---
> .../arch/powerpc/include/arch/special.h | 2 +-
> tools/objtool/special.c | 55 +++++++++----------
> 2 files changed, 28 insertions(+), 29 deletions(-)
>
> diff --git a/tools/objtool/arch/powerpc/include/arch/special.h
> b/tools/objtool/arch/powerpc/include/arch/special.h
> index ffef9ada7133..ede05633c2e4 100644
> --- a/tools/objtool/arch/powerpc/include/arch/special.h
> +++ b/tools/objtool/arch/powerpc/include/arch/special.h
> @@ -6,7 +6,7 @@
> #define EX_ORIG_OFFSET 0
> #define EX_NEW_OFFSET 4
>
> -#define JUMP_ENTRY_SIZE 16
> +#define JUMP_ENTRY_SIZE (8 + elf_class_addrsize(elf)) /* 12 on PPC32, 16 on
> PPC64 */
> #define JUMP_ORIG_OFFSET 0
> #define JUMP_NEW_OFFSET 4
> #define JUMP_KEY_OFFSET 8
> diff --git a/tools/objtool/special.c b/tools/objtool/special.c
> index baa85c31526b..4015c1cd0fe1 100644
> --- a/tools/objtool/special.c
> +++ b/tools/objtool/special.c
> @@ -26,34 +26,6 @@ struct special_entry {
> unsigned char key; /* jump_label key */
> };
>
> -static const struct special_entry entries[] = {
> - {
> - .sec = ".altinstructions",
> - .group = true,
> - .size = ALT_ENTRY_SIZE,
> - .orig = ALT_ORIG_OFFSET,
> - .orig_len = ALT_ORIG_LEN_OFFSET,
> - .new = ALT_NEW_OFFSET,
> - .new_len = ALT_NEW_LEN_OFFSET,
> - .feature = ALT_FEATURE_OFFSET,
> - },
> - {
> - .sec = "__jump_table",
> - .jump_or_nop = true,
> - .size = JUMP_ENTRY_SIZE,
> - .orig = JUMP_ORIG_OFFSET,
> - .new = JUMP_NEW_OFFSET,
> - .key = JUMP_KEY_OFFSET,
> - },
> - {
> - .sec = "__ex_table",
> - .size = EX_ENTRY_SIZE,
> - .orig = EX_ORIG_OFFSET,
> - .new = EX_NEW_OFFSET,
> - },
> - {},
> -};
> -
> void __weak arch_handle_alternative(unsigned short feature, struct
> special_alt *alt)
> {
> }
> @@ -144,6 +116,33 @@ int special_get_alts(struct elf *elf, struct list_head
> *alts)
> unsigned int nr_entries;
> struct special_alt *alt;
> int idx, ret;
> + const struct special_entry entries[] = {
> + {
> + .sec = ".altinstructions",
> + .group = true,
> + .size = ALT_ENTRY_SIZE,
> + .orig = ALT_ORIG_OFFSET,
> + .orig_len = ALT_ORIG_LEN_OFFSET,
> + .new = ALT_NEW_OFFSET,
> + .new_len = ALT_NEW_LEN_OFFSET,
> + .feature = ALT_FEATURE_OFFSET,
> + },
> + {
> + .sec = "__jump_table",
> + .jump_or_nop = true,
> + .size = JUMP_ENTRY_SIZE,
> + .orig = JUMP_ORIG_OFFSET,
> + .new = JUMP_NEW_OFFSET,
> + .key = JUMP_KEY_OFFSET,
> + },
> + {
> + .sec = "__ex_table",
> + .size = EX_ENTRY_SIZE,
> + .orig = EX_ORIG_OFFSET,
> + .new = EX_NEW_OFFSET,
> + },
> + {},
> + };
>
> INIT_LIST_HEAD(alts);
>
> --
> 2.40.1
>
