From 7520ff8c744a704ca39741c165a2360d63a4f47a Mon Sep 17 00:00:00 2001 From: Will Newton Date: Mon, 25 Nov 2013 14:56:28 +0000 Subject: [PATCH] aarch64: Enable ifunc support. Add support for handling the R_AARCH64_IRELATIVE relocation and STT_GNU_IFUNC symbols to the aarch64 port. ports/ChangeLog.aarch64: 2013-11-26 Will Newton * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h. (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass hwcap to ifunc resolver function. (elf_irela): New function. * sysdeps/aarch64/dl-machine.h: Include dl-irel.h. (elf_machine_rela) Handle STT_GNU_IFUNC symbols and R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel): Handle R_AARCH64_IRELATIVE relocations. --- ports/ChangeLog.aarch64 | 10 ++++++++++ ports/sysdeps/aarch64/dl-irel.h | 22 +++++++++++++++++++--- ports/sysdeps/aarch64/dl-machine.h | 20 ++++++++++++++++++++ 3 files changed, 49 insertions(+), 3 deletions(-) diff --git a/ports/ChangeLog.aarch64 b/ports/ChangeLog.aarch64 index 1fd96ee..c6331a4 100644 --- a/ports/ChangeLog.aarch64 +++ b/ports/ChangeLog.aarch64 @@ -1,3 +1,13 @@ +2013-11-26 Will Newton + + * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h. + (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass + hwcap to ifunc resolver function. (elf_irela): New function. + * sysdeps/aarch64/dl-machine.h: Include dl-irel.h. + (elf_machine_rela) Handle STT_GNU_IFUNC symbols and + R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel): + Handle R_AARCH64_IRELATIVE relocations. + 2013-10-30 Mike Frysinger * sysdeps/unix/sysv/linux/aarch64/configure.in: Moved to ... diff --git a/ports/sysdeps/aarch64/dl-irel.h b/ports/sysdeps/aarch64/dl-irel.h index 1a3811e..f37ee39 100644 --- a/ports/sysdeps/aarch64/dl-irel.h +++ b/ports/sysdeps/aarch64/dl-irel.h @@ -22,15 +22,31 @@ #include #include +#include -/* AArch64 does not yet implement IFUNC support. However since - 2011-06-20 provision of a elf_ifunc_invoke has been mandatory. */ +#define ELF_MACHINE_IRELA 1 static inline ElfW(Addr) __attribute ((always_inline)) elf_ifunc_invoke (ElfW(Addr) addr) { - return ((ElfW(Addr) (*) (void)) (addr)) (); + return ((ElfW(Addr) (*) (unsigned long int)) (addr)) (GLRO(dl_hwcap)); +} + +static inline void +__attribute ((always_inline)) +elf_irela (const ElfW(Rela) *reloc) +{ + ElfW(Addr) *const reloc_addr = (void *) reloc->r_offset; + const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info); + + if (__glibc_likely (r_type == R_AARCH64_IRELATIVE)) + { + ElfW(Addr) value = elf_ifunc_invoke (reloc->r_addend); + *reloc_addr = value; + } + else + __libc_fatal ("unexpected reloc type in static binary"); } #endif diff --git a/ports/sysdeps/aarch64/dl-machine.h b/ports/sysdeps/aarch64/dl-machine.h index 71dd6b3..01a214f 100644 --- a/ports/sysdeps/aarch64/dl-machine.h +++ b/ports/sysdeps/aarch64/dl-machine.h @@ -23,6 +23,7 @@ #include #include +#include /* Return nonzero iff ELF header is compatible with the running host. */ static inline int __attribute__ ((unused)) @@ -243,6 +244,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type); ElfW(Addr) value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value; + if (sym != NULL + && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC) + && __glibc_likely (sym->st_shndx != SHN_UNDEF) + && __glibc_likely (!skip_ifunc)) + value = elf_ifunc_invoke (value); + switch (r_type) { case R_AARCH64_COPY: @@ -331,6 +338,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, } break; + case R_AARCH64_IRELATIVE: + value = map->l_addr + reloc->r_addend; + value = elf_ifunc_invoke (value); + *reloc_addr = value; + break; + default: _dl_reloc_bad_type (map, r_type, 0); break; @@ -374,6 +387,13 @@ elf_machine_lazy_rel (struct link_map *map, td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)]) + map->l_addr); } + else if (__glibc_unlikely (r_type == R_AARCH64_IRELATIVE)) + { + ElfW(Addr) value = map->l_addr + reloc->r_addend; + if (__glibc_likely (!skip_ifunc)) + value = elf_ifunc_invoke (value); + *reloc_addr = value; + } else _dl_reloc_bad_type (map, r_type, 1); } -- 2.7.4