From a91e1603afb6704545793e967a1a3dfe96b389de Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 4 Apr 2017 09:05:48 -0700 Subject: Support ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX Mark an ALLOC section, which should be placed in special memory area, with SHF_GNU_MBIND. Its sh_info field indicates the special memory type. GNU_MBIND section names start with ".mbind" so that they are placed as orphan sections by linker. All input GNU_MBIND sections with the same sh_type, sh_flags and sh_info are placed in one output GNU_MBIND section. In executable and shared object, create a GNU_MBIND segment for each GNU_MBIND section and its segment type is PT_GNU_MBIND_LO plus the sh_info value. Each GNU_MBIND segment is aligned at page boundary. The assembler syntax: .section .mbind.foo,"adx",%progbits ^ 0: Special memory type. | 'd' for SHF_GNU_MBIND. .section .mbind.foo,"adx",%progbits,0x1 ^ 1: Special memory type. | 'd' for SHF_GNU_MBIND. .section .mbind.bar,"adG",%progbits,.foo_group,comdat,0x2 ^ 2: Special memory type. | 'd' for SHF_GNU_MBIND. bfd/ * elf.c (get_program_header_size): Add a GNU_MBIND segment for each GNU_MBIND section and align GNU_MBIND section to page size. (_bfd_elf_map_sections_to_segments): Create a GNU_MBIND segment for each GNU_MBIND section. (_bfd_elf_init_private_section_data): Copy sh_info from input for GNU_MBIND section. binutils/ * NEWS: Mention support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX. * readelf.c (get_segment_type): Handle PT_GNU_MBIND_XXX. (get_elf_section_flags): Handle SHF_GNU_MBIND. (process_section_headers): Likewise. * testsuite/binutils-all/mbind1.s: New file. * testsuite/binutils-all/objcopy.exp: Run readelf test on mbind1.s. gas/ * NEWS: Mention support for ELF SHF_GNU_MBIND. * config/obj-elf.c (section_match): New. (get_section): Match both sh_info and group name. (obj_elf_change_section): Add argument for sh_info. Pass both sh_info and group name to get_section. Issue an error for SHF_GNU_MBIND section without SHF_ALLOC. Set sh_info. (obj_elf_parse_section_letters): Set SHF_GNU_MBIND for 'd'. (obj_elf_section): Support SHF_GNU_MBIND section info. * config/obj-elf.h (obj_elf_change_section): Add argument for sh_info. * config/tc-arm.c (start_unwind_section): Pass 0 as sh_info to obj_elf_change_section. * config/tc-ia64.c (obj_elf_vms_common): Likewise. * config/tc-microblaze.c (microblaze_s_data): Likewise. (microblaze_s_sdata): Likewise. (microblaze_s_rdata): Likewise. (microblaze_s_bss): Likewise. * config/tc-mips.c (s_change_section): Likewise. * config/tc-msp430.c (msp430_profiler): Likewise. * config/tc-rx.c (parse_rx_section): Likewise. * config/tc-tic6x.c (tic6x_start_unwind_section): Likewise. * doc/as.texinfo: Document 'd' for SHF_GNU_MBIND. * testsuite/gas/elf/elf.exp: Run section12a, section12b and section13. * testsuite/gas/elf/section10.d: Updated. * testsuite/gas/elf/section10.s: Likewise. * testsuite/gas/elf/section12.s: New file. * testsuite/gas/elf/section12a.d: Likewise. * testsuite/gas/elf/section12b.d: Likewise. * testsuite/gas/elf/section13.l: Likewise. * testsuite/gas/elf/section13.d: Likewise. * testsuite/gas/elf/section13.s: Likewise. include/ * elf/common.h (PT_GNU_MBIND_NUM): New. (PT_GNU_MBIND_LO): Likewise. (PT_GNU_MBIND_HI): Likewise. (SHF_GNU_MBIND): Likewise. ld/ * NEWS: Mention support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX. * emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Place input GNU_MBIND sections with the same type, attributes and sh_info field into a single output GNU_MBIND section. * testsuite/ld-elf/elf.exp: Run mbind2a and mbind2b. * testsuite/ld-elf/mbind1.s: New file. * testsuite/ld-elf/mbind1a.d: Likewise. * testsuite/ld-elf/mbind1b.d: Likewise. * testsuite/ld-elf/mbind1c.d: Likewise. * testsuite/ld-elf/mbind2a.s: Likewise. * testsuite/ld-elf/mbind2b.c: Likewise. --- include/elf/common.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/elf') diff --git a/include/elf/common.h b/include/elf/common.h index 65877fe..484cb48 100644 --- a/include/elf/common.h +++ b/include/elf/common.h @@ -460,6 +460,11 @@ #define PT_GNU_STACK (PT_LOOS + 0x474e551) /* Stack flags */ #define PT_GNU_RELRO (PT_LOOS + 0x474e552) /* Read-only after relocation */ +/* Mbind segments */ +#define PT_GNU_MBIND_NUM 4096 +#define PT_GNU_MBIND_LO (PT_LOOS + 0x474e555) +#define PT_GNU_MBIND_HI (PT_GNU_MBIND_LO + PT_GNU_MBIND_NUM - 1) + /* Program segment permissions, in program header p_flags field. */ #define PF_X (1 << 0) /* Segment is executable */ @@ -543,6 +548,8 @@ are not to be further relocated. */ +#define SHF_GNU_MBIND 0x01000000 /* Mbind section. */ + /* Compression types. */ #define ELFCOMPRESS_ZLIB 1 /* Compressed with zlib. */ #define ELFCOMPRESS_LOOS 0x60000000 /* OS-specific semantics, lo */ -- cgit v1.1