binutils-gdb/bfd/elf32-ppc.h
Alan Modra 1be5d8d3bb PowerPC PLT speculative execution barriers
Spectre variant 2 mitigation for PowerPC and PowerPC64.

bfd/
	* elf32-ppc.c (GLINK_ENTRY_SIZE): Handle speculation barrier.
	(CRSETEQ, BEQCTRM): Define.
	(is_nonpic_glink_stub): Don't check bctr.
	(ppc_elf_link_hash_table_create): Init new ppc_elf_params field.
	(ppc_elf_relax_section): Size speculation barrier.
	(output_bctr): New function.
	(write_glink_stub): Use output_bctr.
	(ppc_elf_relocate_section): Use output_bctr for long branch stub.
	(ppc_elf_finish_dynamic_symbol): Likewise.
	(ppc_elf_finish_dynamic_sections): Use output_bctr.
	* elf32-ppc.h (struct ppc_elf_params): Add speculate_indirect_jumps.
	* elf64-ppc.c (CRSETEQ, BEQCTRM, BEQCTRLM): Define.
	(GLINK_PLTRESOLVE_SIZE): Size speculation barrier.
	(size_global_entry_stubs): Handle speculation barrier sizing.
	(plt_stub_size): Likewise.
	(output_bctr): New function.
	(build_plt_stub, build_tls_get_addr_stub): Output speculation
	barrier.
	(ppc_build_one_stub): Likewise for ppc_stub_plt_branch.
	(ppc_size_one_stub): Size speculation barrier in ppc_stub_plt_branch.
	(build_global_entry_stubs): Output speculation barrier.
	(ppc64_elf_build_stubs): Likewise in __glink_PLTresolve stub.
	* elf64-ppc.h (struct ppc64_elf_params): Add speculate_indirect_jumps.
gold/
	* options.h (speculate_indirect_jumps): New option.
	* powerpc.cc (beqctrm, beqctrlm, crseteq): New insn constants.
	(output_bctr): New function.
	(Stub_table::plt_call_size): Add space for speculation barrier.
	(Stub_table::branch_stub_size): Likewise.
	(Output_data_glink::pltresolve_size): Likewise.
	(Stub_table::do_write): Output speculation barriers.
ld/
	* emultempl/ppc32elf.em (params): Init new field.
	(OPTION_SPECULATE_INDIRECT_JUMPS): Define.
	(OPTION_NO_SPECULATE_INDIRECT_JUMPS): Define.
	(PARSE_AND_LIST_LONGOPTS): Handle new options.
	(PARSE_AND_LIST_ARGS_CASES): Likewise.
	(PARSE_AND_LIST_OPTIONS): Likewise.
	* emultempl/ppc64elf.em (params): Init new field.
	(OPTION_SPECULATE_INDIRECT_JUMPS): Define.
	(OPTION_NO_SPECULATE_INDIRECT_JUMPS): Define.
	(PARSE_AND_LIST_LONGOPTS): Handle --speculate-indirect-jumps.
	(PARSE_AND_LIST_OPTIONS): Likewise.
	(PARSE_AND_LIST_ARGS_CASES): Likewise.
	* ld.texinfo (--no-plt-thread-safe): Correct itemx.
	(--speculate-indirect-jumps): Document.
	* testsuite/ld-powerpc/elfv2exe.d,
	* testsuite/ld-powerpc/elfv2so.d,
	* testsuite/ld-powerpc/relbrlt.d,
	* testsuite/ld-powerpc/powerpc.exp: Disable plt alignment and
	speculation barriers on various tests.
2018-01-17 18:52:57 +10:30

72 lines
2.4 KiB
C

/* PowerPC-specific support for 64-bit ELF.
Copyright (C) 2003-2018 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
enum ppc_elf_plt_type
{
PLT_UNSET,
PLT_OLD,
PLT_NEW,
PLT_VXWORKS
};
/* Various options passed from the linker to bfd backend. */
struct ppc_elf_params
{
/* Chooses the type of .plt. */
enum ppc_elf_plt_type plt_style;
/* Set if individual PLT call stubs should be aligned. */
int plt_stub_align;
/* Clear if PLT call stubs should use a speculative execution barrier. */
int speculate_indirect_jumps;
/* Whether to emit symbols for stubs. */
int emit_stub_syms;
/* Whether to emit special stub for __tls_get_addr calls. */
int no_tls_get_addr_opt;
/* Insert trampolines for branches that won't reach their destination. */
int branch_trampolines;
/* Avoid execution falling into new page. */
int ppc476_workaround;
unsigned int pagesize_p2;
/* The bfd backend detected a non-PIC reference to a protected symbol
defined in a shared library. */
int pic_fixup;
/* Relocate 16A relocs as 16D and vice versa. */
int vle_reloc_fixup;
bfd_vma pagesize;
};
void ppc_elf_link_params (struct bfd_link_info *, struct ppc_elf_params *);
int ppc_elf_select_plt_layout (bfd *, struct bfd_link_info *);
asection *ppc_elf_tls_setup (bfd *, struct bfd_link_info *);
bfd_boolean ppc_elf_tls_optimize (bfd *, struct bfd_link_info *);
void ppc_elf_maybe_strip_sdata_syms (struct bfd_link_info *);
extern bfd_boolean ppc_elf_modify_segment_map (bfd *,
struct bfd_link_info * ATTRIBUTE_UNUSED);
extern bfd_boolean ppc_elf_section_processing (bfd *, Elf_Internal_Shdr *);