From 4ab7674f5951ac6a8ac4fa8828090edb64a4771f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:39 -0700 Subject: objtool: Make jump label hack optional Objtool secretly does a jump label hack to overcome the limitations of the toolchain. Make the hack explicit (and optional for other arches) by turning it into a cmdline option and kernel config option. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/3bdcbfdd27ecb01ddec13c04bdf756a583b13d24.1650300597.git.jpoimboe@redhat.com --- tools/objtool/builtin-check.c | 37 +++++++++++++++++++++++++++++-------- 1 file changed, 29 insertions(+), 8 deletions(-) (limited to 'tools/objtool/builtin-check.c') diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index c8c4d2bab42f..b2c626d9e2bf 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -31,8 +31,28 @@ static int parse_dump(const struct option *opt, const char *str, int unset) return -1; } +static int parse_hacks(const struct option *opt, const char *str, int unset) +{ + bool found = false; + + /* + * Use strstr() as a lazy method of checking for comma-separated + * options. + * + * No string provided == enable all options. + */ + + if (!str || strstr(str, "jump_label")) { + opts.hack_jump_label = true; + found = true; + } + + return found ? 0 : -1; +} + const struct option check_options[] = { OPT_GROUP("Actions:"), + OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label", "patch toolchain bugs/limitations", parse_hacks), OPT_BOOLEAN('i', "ibt", &opts.ibt, "validate and annotate IBT"), OPT_BOOLEAN('m', "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"), OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"), @@ -87,14 +107,15 @@ int cmd_parse_options(int argc, const char **argv, const char * const usage[]) static bool opts_valid(void) { - if (opts.ibt || - opts.mcount || - opts.noinstr || - opts.orc || - opts.retpoline || - opts.sls || - opts.stackval || - opts.static_call || + if (opts.hack_jump_label || + opts.ibt || + opts.mcount || + opts.noinstr || + opts.orc || + opts.retpoline || + opts.sls || + opts.stackval || + opts.static_call || opts.uaccess) { if (opts.dump_orc) { fprintf(stderr, "--dump can't be combined with other options\n"); -- cgit v1.2.3