When objtool discovers an issue, it's very common for it to flood the
terminal with a lot of duplicate warnings. For example:
warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch
warning: objtool: rtlwifi_rate_mapping()+0x2f3: frame pointer state mismatch
warning: objtool: rtlwifi_rate_mapping()+0x2ff: frame pointer state mismatch
warning: objtool: rtlwifi_rate_mapping()+0x30b: frame pointer state mismatch
...
The first warning is usually all you need. Change it to only warn once
per function.
Suggested-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
tools/objtool/builtin-check.c | 48 ++++++++++++++++++++++---------------------
1 file changed, 25 insertions(+), 23 deletions(-)
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index bfeee22..7515cb2 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -800,7 +800,7 @@ static int validate_branch(struct objtool_file *file,
struct instruction *insn;
struct section *sec;
unsigned char state;
- int ret, warnings = 0;
+ int ret;
insn = first;
sec = insn->sec;
@@ -809,7 +809,7 @@ static int validate_branch(struct objtool_file *file,
if (insn->alt_group && list_empty(&insn->alts)) {
WARN_FUNC("don't know how to handle branch to middle of alternative instruction group",
sec, insn->offset);
- warnings++;
+ return 1;
}
while (1) {
@@ -817,10 +817,10 @@ static int validate_branch(struct objtool_file *file,
if (frame_state(insn->state) != frame_state(state)) {
WARN_FUNC("frame pointer state mismatch",
sec, insn->offset);
- warnings++;
+ return 1;
}
- return warnings;
+ return 0;
}
/*
@@ -828,14 +828,15 @@ static int validate_branch(struct objtool_file *file,
* the next function.
*/
if (is_fentry_call(insn) && (state & STATE_FENTRY))
- return warnings;
+ return 0;
insn->visited = true;
insn->state = state;
list_for_each_entry(alt, &insn->alts, list) {
ret = validate_branch(file, alt->insn, state);
- warnings += ret;
+ if (ret)
+ return 1;
}
switch (insn->type) {
@@ -845,7 +846,7 @@ static int validate_branch(struct objtool_file *file,
if (state & STATE_FP_SAVED) {
WARN_FUNC("duplicate frame pointer save",
sec, insn->offset);
- warnings++;
+ return 1;
}
state |= STATE_FP_SAVED;
}
@@ -856,7 +857,7 @@ static int validate_branch(struct objtool_file *file,
if (state & STATE_FP_SETUP) {
WARN_FUNC("duplicate frame pointer setup",
sec, insn->offset);
- warnings++;
+ return 1;
}
state |= STATE_FP_SETUP;
}
@@ -875,9 +876,9 @@ static int validate_branch(struct objtool_file *file,
if (!nofp && has_modified_stack_frame(insn)) {
WARN_FUNC("return without frame pointer restore",
sec, insn->offset);
- warnings++;
+ return 1;
}
- return warnings;
+ return 0;
case INSN_CALL:
if (is_fentry_call(insn)) {
@@ -887,16 +888,16 @@ static int validate_branch(struct objtool_file *file,
ret = dead_end_function(file, insn->call_dest);
if (ret == 1)
- return warnings;
+ return 0;
if (ret == -1)
- warnings++;
+ return 1;
/* fallthrough */
case INSN_CALL_DYNAMIC:
if (!nofp && !has_valid_stack_frame(insn)) {
WARN_FUNC("call without frame pointer save/setup",
sec, insn->offset);
- warnings++;
+ return 1;
}
break;
@@ -905,15 +906,16 @@ static int validate_branch(struct objtool_file *file,
if (insn->jump_dest) {
ret = validate_branch(file, insn->jump_dest,
state);
- warnings += ret;
+ if (ret)
+ return 1;
} else if (has_modified_stack_frame(insn)) {
WARN_FUNC("sibling call from callable instruction with changed frame pointer",
sec, insn->offset);
- warnings++;
+ return 1;
} /* else it's a sibling call */
if (insn->type == INSN_JUMP_UNCONDITIONAL)
- return warnings;
+ return 0;
break;
@@ -922,13 +924,13 @@ static int validate_branch(struct objtool_file *file,
has_modified_stack_frame(insn)) {
WARN_FUNC("sibling call from callable instruction with changed frame pointer",
sec, insn->offset);
- warnings++;
+ return 1;
}
- return warnings;
+ return 0;
case INSN_BUG:
- return warnings;
+ return 0;
default:
break;
@@ -937,12 +939,11 @@ static int validate_branch(struct objtool_file *file,
insn = next_insn_same_sec(file, insn);
if (!insn) {
WARN("%s: unexpected end of section", sec->name);
- warnings++;
- return warnings;
+ return 1;
}
}
- return warnings;
+ return 0;
}
static bool is_gcov_insn(struct instruction *insn)
@@ -1055,7 +1056,8 @@ static int validate_functions(struct objtool_file *file)
if (insn->visited)
continue;
- if (!ignore_unreachable_insn(func, insn)) {
+ if (!ignore_unreachable_insn(func, insn) &&
+ !warnings) {
WARN_FUNC("function has unreachable instruction", insn->sec, insn->offset);
warnings++;
}
--
2.4.3
--
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