From f2d3a250897133cc36c13a641bd6a9b4dd5ad234 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 8 Mar 2022 16:30:13 +0100 Subject: objtool: Add --dry-run Add a --dry-run argument to skip writing the modifications. This is convenient for debugging. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Kees Cook Reviewed-by: Miroslav Benes Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154317.282720146@infradead.org --- tools/objtool/builtin-check.c | 3 ++- tools/objtool/elf.c | 3 +++ tools/objtool/include/objtool/builtin.h | 2 +- 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 38070f26105b..853af934c9fd 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -20,7 +20,7 @@ #include bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, - validate_dup, vmlinux, mcount, noinstr, backup, sls; + validate_dup, vmlinux, mcount, noinstr, backup, sls, dryrun; static const char * const check_usage[] = { "objtool check [] file.o", @@ -46,6 +46,7 @@ const struct option check_options[] = { OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"), OPT_BOOLEAN('B', "backup", &backup, "create .orig files before modification"), OPT_BOOLEAN('S', "sls", &sls, "validate straight-line-speculation"), + OPT_BOOLEAN(0, "dry-run", &dryrun, "don't write the modifications"), OPT_END(), }; diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 4b384c907027..456ac2206404 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -1019,6 +1019,9 @@ int elf_write(struct elf *elf) struct section *sec; Elf_Scn *s; + if (dryrun) + return 0; + /* Update changed relocation sections and section headers: */ list_for_each_entry(sec, &elf->sections, list) { if (sec->changed) { diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index 89ba869ed08f..7b4b124b9032 100644 --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -9,7 +9,7 @@ extern const struct option check_options[]; extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, - validate_dup, vmlinux, mcount, noinstr, backup, sls; + validate_dup, vmlinux, mcount, noinstr, backup, sls, dryrun; extern int cmd_parse_options(int argc, const char **argv, const char * const usage[]); -- cgit v1.2.3-59-g8ed1b