The following commit has been merged into the x86/core branch of tip: Commit-ID: 4ecdc0265dc911adba0772fd6e816d48da678fe7 Gitweb: https://git.kernel.org/tip/4ecdc0265dc911adba0772fd6e816d48da678fe7 Author: Peter Zijlstra <[email protected]> AuthorDate: Fri, 26 Mar 2021 16:12:13 +01:00 Committer: Borislav Petkov <[email protected]> CommitterDate: Thu, 01 Apr 2021 13:25:38 +02:00
objtool: Cache instruction relocs Track the reloc of instructions to avoid having to look them up again later. (Technically x86 instructions can have two relocations, but not jumps and calls, for which we're using this.) Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Miroslav Benes <[email protected]> Link: https://lkml.kernel.org/r/[email protected] --- tools/objtool/check.c | 28 ++++++++++++++++++++------ tools/objtool/include/objtool/check.h | 1 +- 2 files changed, 23 insertions(+), 6 deletions(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 77074db..1f4154f 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -797,6 +797,25 @@ __weak bool arch_is_retpoline(struct symbol *sym) return false; } +#define NEGATIVE_RELOC ((void *)-1L) + +static struct reloc *insn_reloc(struct objtool_file *file, struct instruction *insn) +{ + if (insn->reloc == NEGATIVE_RELOC) + return NULL; + + if (!insn->reloc) { + insn->reloc = find_reloc_by_dest_range(file->elf, insn->sec, + insn->offset, insn->len); + if (!insn->reloc) { + insn->reloc = NEGATIVE_RELOC; + return NULL; + } + } + + return insn->reloc; +} + /* * Find the destination instructions for all jumps. */ @@ -811,8 +830,7 @@ static int add_jump_destinations(struct objtool_file *file) if (!is_static_jump(insn)) continue; - reloc = find_reloc_by_dest_range(file->elf, insn->sec, - insn->offset, insn->len); + reloc = insn_reloc(file, insn); if (!reloc) { dest_sec = insn->sec; dest_off = arch_jump_destination(insn); @@ -944,8 +962,7 @@ static int add_call_destinations(struct objtool_file *file) if (insn->type != INSN_CALL) continue; - reloc = find_reloc_by_dest_range(file->elf, insn->sec, - insn->offset, insn->len); + reloc = insn_reloc(file, insn); if (!reloc) { dest_off = arch_jump_destination(insn); insn->call_dest = find_call_destination(insn->sec, dest_off); @@ -1144,8 +1161,7 @@ static int handle_group_alt(struct objtool_file *file, * alternatives code can adjust the relative offsets * accordingly. */ - alt_reloc = find_reloc_by_dest_range(file->elf, insn->sec, - insn->offset, insn->len); + alt_reloc = insn_reloc(file, insn); if (alt_reloc && !arch_support_alt_relocation(special_alt, insn, alt_reloc)) { diff --git a/tools/objtool/include/objtool/check.h b/tools/objtool/include/objtool/check.h index e5528ce..56d50bc 100644 --- a/tools/objtool/include/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -56,6 +56,7 @@ struct instruction { struct instruction *jump_dest; struct instruction *first_jump_src; struct reloc *jump_table; + struct reloc *reloc; struct list_head alts; struct symbol *func; struct list_head stack_ops;
