diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2024-11-28 10:38:52 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2024-12-02 12:01:41 +0100 |
| commit | 2116b349e29a2e9ba17ea2e45b31234e4b350793 (patch) | |
| tree | 6dd85584c3a83a90e0bc469b1fc2854688624044 /tools | |
| parent | 40384c840ea1944d7c5a392e8975ed088ecf0b37 (diff) | |
objtool: Generic annotation infrastructure
Avoid endless .discard.foo sections for each annotation, create a
single .discard.annotate_insn section that takes an annotation type along
with the instruction.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/20241128094310.932794537@infradead.org
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/objtool/check.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 4ce176ad411fb..b0efc8ee16d6d 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2373,6 +2373,49 @@ static int read_unwind_hints(struct objtool_file *file) return 0; } +static int read_annotate(struct objtool_file *file, void (*func)(int type, struct instruction *insn)) +{ + struct section *sec; + struct instruction *insn; + struct reloc *reloc; + int type; + + sec = find_section_by_name(file->elf, ".discard.annotate_insn"); + if (!sec) + return 0; + + if (!sec->rsec) + return 0; + + if (sec->sh.sh_entsize != 8) { + static bool warned = false; + if (!warned) { + WARN("%s: dodgy linker, sh_entsize != 8", sec->name); + warned = true; + } + sec->sh.sh_entsize = 8; + } + + for_each_reloc(sec->rsec, reloc) { + type = *(u32 *)(sec->data->d_buf + (reloc_idx(reloc) * sec->sh.sh_entsize) + 4); + + insn = find_insn(file, reloc->sym->sec, + reloc->sym->offset + reloc_addend(reloc)); + if (!insn) { + WARN("bad .discard.annotate_insn entry: %d of type %d", reloc_idx(reloc), type); + return -1; + } + + func(type, insn); + } + + return 0; +} + +static void __annotate_nop(int type, struct instruction *insn) +{ +} + static int read_noendbr_hints(struct objtool_file *file) { struct instruction *insn; @@ -2670,6 +2713,8 @@ static int decode_sections(struct objtool_file *file) if (ret) return ret; + read_annotate(file, __annotate_nop); + /* * Must be before read_unwind_hints() since that needs insn->noendbr. */ |