[PATCH 10/48] objtool/klp: Fix --debug-checksum for duplicate symbol names

[Josh Poimboeuf]

find_symbol_by_name() only returns the first match, so
--debug-checksum=<func> silently ignores any subsequent duplicately
named functions after the first.

Add a new iterate_sym_by_name() to fix that.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
 tools/objtool/check.c               | 19 ++++++++++++++-----
 tools/objtool/elf.c                 | 12 ++++++++++++
 tools/objtool/include/objtool/elf.h |  3 +++
 3 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 5722d4568401..f14212a8c179 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -3657,6 +3657,17 @@ static bool skip_alt_group(struct instruction *insn)
 	return alt_insn->type == INSN_CLAC || alt_insn->type == INSN_STAC;
 }
 
+static void enable_debug_checksum_cb(struct symbol *sym, void *d)
+{
+	bool *found = d;
+
+	if (!is_func_sym(sym))
+		return;
+
+	sym->debug_checksum = 1;
+	*found = true;
+}
+
 static int checksum_debug_init(struct objtool_file *file)
 {
 	char *dup, *s;
@@ -3672,18 +3683,16 @@ static int checksum_debug_init(struct objtool_file *file)
 
 	s = dup;
 	while (*s) {
-		struct symbol *func;
+		bool found = false;
 		char *comma;
 
 		comma = strchr(s, ',');
 		if (comma)
 			*comma = '\0';
 
-		func = find_symbol_by_name(file->elf, s);
-		if (!func || !is_func_sym(func))
+		iterate_sym_by_name(file->elf, s, enable_debug_checksum_cb, &found);
+		if (!found)
 			WARN("--debug-checksum: can't find '%s'", s);
-		else
-			func->debug_checksum = 1;
 
 		if (!comma)
 			break;
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index ac9da81a7a2f..a5486e172e5c 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -335,6 +335,18 @@ void iterate_global_symbol_by_demangled_name(const struct elf *elf,
 	}
 }
 
+void iterate_sym_by_name(const struct elf *elf, const char *name,
+			 void (*process)(struct symbol *sym, void *data),
+			 void *data)
+{
+	struct symbol *sym;
+
+	elf_hash_for_each_possible(symbol_name, sym, name_hash, str_hash_demangled(name)) {
+		if (!strcmp(sym->name, name))
+			process(sym, data);
+	}
+}
+
 struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *sec,
 				     unsigned long offset, unsigned int len)
 {
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index c61bd57767f9..cd5844c7b4e2 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -189,6 +189,9 @@ struct symbol *find_global_symbol_by_name(const struct elf *elf, const char *nam
 void iterate_global_symbol_by_demangled_name(const struct elf *elf, const char *demangled_name,
 					     void (*process)(struct symbol *sym, void *data),
 					     void *data);
+void iterate_sym_by_name(const struct elf *elf, const char *name,
+			 void (*process)(struct symbol *sym, void *data),
+			 void *data);
 struct symbol *find_symbol_containing(const struct section *sec, unsigned long offset);
 int find_symbol_hole_containing(const struct section *sec, unsigned long offset);
 struct reloc *find_reloc_by_dest(const struct elf *elf, struct section *sec, unsigned long offset);
-- 
2.53.0