From 96db4a988d653a7f18b518c25367f7bf238f4667 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 8 Mar 2022 16:30:52 +0100 Subject: objtool: Read the NOENDBR annotation Read the new NOENDBR annotation. While there, attempt to not bloat struct instruction. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154319.586815435@infradead.org --- tools/objtool/check.c | 27 +++++++++++++++++++++++++++ tools/objtool/include/objtool/check.h | 13 ++++++++++--- 2 files changed, 37 insertions(+), 3 deletions(-) (limited to 'tools/objtool') diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 894c9a722555..63993945ff9f 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1866,6 +1866,29 @@ static int read_unwind_hints(struct objtool_file *file) return 0; } +static int read_noendbr_hints(struct objtool_file *file) +{ + struct section *sec; + struct instruction *insn; + struct reloc *reloc; + + sec = find_section_by_name(file->elf, ".rela.discard.noendbr"); + if (!sec) + return 0; + + list_for_each_entry(reloc, &sec->reloc_list, list) { + insn = find_insn(file, reloc->sym->sec, reloc->sym->offset + reloc->addend); + if (!insn) { + WARN("bad .discard.noendbr entry"); + return -1; + } + + insn->noendbr = 1; + } + + return 0; +} + static int read_retpoline_hints(struct objtool_file *file) { struct section *sec; @@ -2099,6 +2122,10 @@ static int decode_sections(struct objtool_file *file) if (ret) return ret; + ret = read_noendbr_hints(file); + if (ret) + return ret; + /* * Must be before add_{jump_call}_destination. */ diff --git a/tools/objtool/include/objtool/check.h b/tools/objtool/include/objtool/check.h index 6cfff078897f..f10d7374f388 100644 --- a/tools/objtool/include/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -45,11 +45,18 @@ struct instruction { unsigned int len; enum insn_type type; unsigned long immediate; - bool dead_end, ignore, ignore_alts; - bool hint; - bool retpoline_safe; + + u8 dead_end : 1, + ignore : 1, + ignore_alts : 1, + hint : 1, + retpoline_safe : 1, + noendbr : 1; + /* 2 bit hole */ s8 instr; u8 visited; + /* u8 hole */ + struct alt_group *alt_group; struct symbol *call_dest; struct instruction *jump_dest; -- cgit v1.2.3