From 72064474964724c59ddff58a581a31b1ede75cf9 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:37 -0700 Subject: [PATCH] objtool: Make stack validation frame-pointer-specific Now that CONFIG_STACK_VALIDATION is frame-pointer specific, do the same for the '--stackval' option. Now the '--no-fp' option is redundant and can be removed. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/f563fa064b3b63d528de250c72012d49e14742a3.1650300597.git.jpoimboe@redhat.com --- scripts/Makefile.build | 1 - scripts/link-vmlinux.sh | 4 ---- tools/objtool/builtin-check.c | 3 +-- tools/objtool/check.c | 4 ++-- tools/objtool/include/objtool/builtin.h | 1 - 5 files changed, 3 insertions(+), 10 deletions(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 0f73e02b7cf1..6eb99cb08821 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -235,7 +235,6 @@ objtool_args = \ $(if $(CONFIG_STACK_VALIDATION), --stackval) \ $(if $(CONFIG_X86_SMAP), --uaccess) \ $(if $(part-of-module), --module) \ - $(if $(CONFIG_FRAME_POINTER),, --no-fp) \ $(if $(CONFIG_GCOV_KERNEL), --no-unreachable) cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $@) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 5101a7fbfaaf..1be01163a9c5 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -155,10 +155,6 @@ objtool_link() if [ -n "${objtoolopt}" ]; then - if ! is_enabled CONFIG_FRAME_POINTER; then - objtoolopt="${objtoolopt} --no-fp" - fi - if is_enabled CONFIG_GCOV_KERNEL; then objtoolopt="${objtoolopt} --no-unreachable" fi diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index d4e6930ad0a0..30971cc50c63 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -39,7 +39,7 @@ const struct option check_options[] = { OPT_BOOLEAN('o', "orc", &opts.orc, "generate ORC metadata"), OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"), OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"), - OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate stack unwinding rules"), + OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate frame pointer rules"), OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"), OPT_CALLBACK_OPTARG(0, "dump", NULL, NULL, "orc", "dump metadata", parse_dump), @@ -49,7 +49,6 @@ const struct option check_options[] = { OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"), OPT_BOOLEAN(0, "lto", &opts.lto, "whole-archive like runs"), OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"), - OPT_BOOLEAN(0, "no-fp", &opts.no_fp, "skip frame pointer validation"), OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"), OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"), OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"), diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 27126fff91dc..3e02126738a1 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2806,7 +2806,7 @@ static int update_cfi_state(struct instruction *insn, } /* detect when asm code uses rbp as a scratch register */ - if (!opts.no_fp && insn->func && op->src.reg == CFI_BP && + if (opts.stackval && insn->func && op->src.reg == CFI_BP && cfa->base != CFI_BP) cfi->bp_scratch = true; break; @@ -3279,7 +3279,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, if (ret) return ret; - if (!opts.no_fp && func && !is_fentry_call(insn) && + if (opts.stackval && func && !is_fentry_call(insn) && !has_valid_stack_frame(&state)) { WARN_FUNC("call without frame pointer save/setup", sec, insn->offset); diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index 8618585bb742..24a7ff4f37cc 100644 --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -27,7 +27,6 @@ struct opts { bool dryrun; bool lto; bool module; - bool no_fp; bool no_unreachable; bool sec_address; bool stats;