objtool: Parse options from OBJTOOL_ARGS

Teach objtool to parse options from the OBJTOOL_ARGS environment
variable.

This enables things like:

  $ OBJTOOL_ARGS="--backup" make O=defconfig-build/ kernel/ponies.o

to obtain both defconfig-build/kernel/ponies.o{,.orig} and easily
inspect what objtool actually did.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20210226110004.252553847@infradead.org
This commit is contained in:
Peter Zijlstra 2021-02-26 11:32:30 +01:00 committed by Ingo Molnar
parent a2f605f9ff
commit 900b4df347

View File

@ -15,6 +15,7 @@
#include <subcmd/parse-options.h>
#include <string.h>
#include <stdlib.h>
#include <objtool/builtin.h>
#include <objtool/objtool.h>
@ -26,6 +27,11 @@ static const char * const check_usage[] = {
NULL,
};
static const char * const env_usage[] = {
"OBJTOOL_ARGS=\"<options>\"",
NULL,
};
const struct option check_options[] = {
OPT_BOOLEAN('f', "no-fp", &no_fp, "Skip frame pointer validation"),
OPT_BOOLEAN('u', "no-unreachable", &no_unreachable, "Skip 'unreachable instruction' warnings"),
@ -44,6 +50,25 @@ const struct option check_options[] = {
int cmd_parse_options(int argc, const char **argv, const char * const usage[])
{
const char *envv[16] = { };
char *env;
int envc;
env = getenv("OBJTOOL_ARGS");
if (env) {
envv[0] = "OBJTOOL_ARGS";
for (envc = 1; envc < ARRAY_SIZE(envv); ) {
envv[envc++] = env;
env = strchr(env, ' ');
if (!env)
break;
*env = '\0';
env++;
}
parse_options(envc, envv, check_options, env_usage, 0);
}
argc = parse_options(argc, argv, check_options, usage, 0);
if (argc != 1)
usage_with_options(usage, check_options);