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| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2023-06-05 09:12:21 -0700 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@kernel.org> | 2023-06-07 10:03:11 -0700 |
| commit | 1e4b619185e83e54aca617cf5070c64a88fe936b (patch) | |
| tree | 41fd2c6f5afb7ccc77947cd8f36228967658c48a /tools/objtool | |
| parent | ac27ecf68a1ada240bb71531dc2d30cde04ad70a (diff) | |
| download | linux-1e4b619185e83e54aca617cf5070c64a88fe936b.tar.gz linux-1e4b619185e83e54aca617cf5070c64a88fe936b.tar.bz2 linux-1e4b619185e83e54aca617cf5070c64a88fe936b.zip | |
objtool: Allow stack operations in UNWIND_HINT_UNDEFINED regions
If the code specified UNWIND_HINT_UNDEFINED, skip the "undefined stack
state" warning due to a stack operation. Just ignore the stack op and
continue to propagate the undefined state.
Link: https://lore.kernel.org/r/820c5b433f17c84e8761fb7465a8d319d706b1cf.1685981486.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/check.c | 12 | ||||
| -rw-r--r-- | tools/objtool/include/objtool/cfi.h | 1 |
2 files changed, 13 insertions, 0 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 4b869de7e827..b11c25a715ac 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -33,6 +33,7 @@ static unsigned long nr_cfi, nr_cfi_reused, nr_cfi_cache; static struct cfi_init_state initial_func_cfi; static struct cfi_state init_cfi; static struct cfi_state func_cfi; +static struct cfi_state force_undefined_cfi; struct instruction *find_insn(struct objtool_file *file, struct section *sec, unsigned long offset) @@ -2240,6 +2241,11 @@ static int read_unwind_hints(struct objtool_file *file) insn->hint = true; + if (hint->type == UNWIND_HINT_TYPE_UNDEFINED) { + insn->cfi = &force_undefined_cfi; + continue; + } + if (hint->type == UNWIND_HINT_TYPE_SAVE) { insn->hint = false; insn->save = true; @@ -2793,6 +2799,10 @@ static int update_cfi_state(struct instruction *insn, struct cfi_reg *cfa = &cfi->cfa; struct cfi_reg *regs = cfi->regs; + /* ignore UNWIND_HINT_UNDEFINED regions */ + if (cfi->force_undefined) + return 0; + /* stack operations don't make sense with an undefined CFA */ if (cfa->base == CFI_UNDEFINED) { if (insn_func(insn)) { @@ -4607,6 +4617,8 @@ int check(struct objtool_file *file) init_cfi_state(&init_cfi); init_cfi_state(&func_cfi); set_func_state(&func_cfi); + init_cfi_state(&force_undefined_cfi); + force_undefined_cfi.force_undefined = true; if (!cfi_hash_alloc(1UL << (file->elf->symbol_bits - 3))) goto out; diff --git a/tools/objtool/include/objtool/cfi.h b/tools/objtool/include/objtool/cfi.h index b1258e79a1b7..c8a6bec4f6b9 100644 --- a/tools/objtool/include/objtool/cfi.h +++ b/tools/objtool/include/objtool/cfi.h @@ -36,6 +36,7 @@ struct cfi_state { bool drap; bool signal; bool end; + bool force_undefined; }; #endif /* _OBJTOOL_CFI_H */ |