4 files changed, 29 insertions, 23 deletions

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 437194fe0434..dc5c3bb69d73 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -768,15 +768,16 @@ static int find_symbol_cb(void *arg, const char *name, char type,
 	return 1;
 }
 
-u64 kallsyms__get_function_start(const char *kallsyms_filename,
-				 const char *symbol_name)
+int kallsyms__get_function_start(const char *kallsyms_filename,
+				 const char *symbol_name, u64 *addr)
 {
 	struct process_symbol_args args = { .name = symbol_name, };
 
 	if (kallsyms__parse(kallsyms_filename, &args, find_symbol_cb) <= 0)
-		return 0;
+		return -1;
 
-	return args.start;
+	*addr = args.start;
+	return 0;
 }
 
 int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index cfbe32bd7413..27ac047490c3 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -675,8 +675,8 @@ size_t perf_event__fprintf_cpu_map(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_namespaces(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf(union perf_event *event, FILE *fp);
 
-u64 kallsyms__get_function_start(const char *kallsyms_filename,
-				 const char *symbol_name);
+int kallsyms__get_function_start(const char *kallsyms_filename,
+				 const char *symbol_name, u64 *addr);
 
 void *cpu_map_data__alloc(struct cpu_map *map, size_t *size, u16 *type, int *max);
 void  cpu_map_data__synthesize(struct cpu_map_data *data, struct cpu_map *map,
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 7a47f52ccfcc..d97e014c3df3 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -796,11 +796,11 @@ const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL};
  * Returns the name of the start symbol in *symbol_name. Pass in NULL as
  * symbol_name if it's not that important.
  */
-static u64 machine__get_running_kernel_start(struct machine *machine,
-					     const char **symbol_name)
+static int machine__get_running_kernel_start(struct machine *machine,
+					     const char **symbol_name, u64 *start)
 {
 	char filename[PATH_MAX];
-	int i;
+	int i, err = -1;
 	const char *name;
 	u64 addr = 0;
 
@@ -810,21 +810,28 @@ static u64 machine__get_running_kernel_start(struct machine *machine,
 		return 0;
 
 	for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
-		addr = kallsyms__get_function_start(filename, name);
-		if (addr)
+		err = kallsyms__get_function_start(filename, name, &addr);
+		if (!err)
 			break;
 	}
 
+	if (err)
+		return -1;
+
 	if (symbol_name)
 		*symbol_name = name;
 
-	return addr;
+	*start = addr;
+	return 0;
 }
 
 int __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
 {
 	int type;
-	u64 start = machine__get_running_kernel_start(machine, NULL);
+	u64 start = 0;
+
+	if (machine__get_running_kernel_start(machine, NULL, &start))
+		return -1;
 
 	/* In case of renewal the kernel map, destroy previous one */
 	machine__destroy_kernel_maps(machine);
@@ -1185,8 +1192,8 @@ static int machine__create_modules(struct machine *machine)
 int machine__create_kernel_maps(struct machine *machine)
 {
 	struct dso *kernel = machine__get_kernel(machine);
-	const char *name;
-	u64 addr;
+	const char *name = NULL;
+	u64 addr = 0;
 	int ret;
 
 	if (kernel == NULL)
@@ -1211,8 +1218,7 @@ int machine__create_kernel_maps(struct machine *machine)
 	 */
 	map_groups__fixup_end(&machine->kmaps);
 
-	addr = machine__get_running_kernel_start(machine, &name);
-	if (!addr) {
+	if (machine__get_running_kernel_start(machine, &name, &addr)) {
 	} else if (maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps, name, addr)) {
 		machine__destroy_kernel_maps(machine);
 		return -1;
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 2cb7665e9973..b349e8eda0e2 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -466,7 +466,7 @@ void dso__insert_symbol(struct dso *dso, enum map_type type, struct symbol *sym)
 struct symbol *dso__find_symbol(struct dso *dso,
 				enum map_type type, u64 addr)
 {
-	if (dso->last_find_result[type].addr != addr) {
+	if (dso->last_find_result[type].addr != addr || dso->last_find_result[type].symbol == NULL) {
 		dso->last_find_result[type].addr   = addr;
 		dso->last_find_result[type].symbol = symbols__find(&dso->symbols[type], addr);
 	}
@@ -1075,8 +1075,9 @@ static int validate_kcore_addresses(const char *kallsyms_filename,
 	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
 		u64 start;
 
-		start = kallsyms__get_function_start(kallsyms_filename,
-						     kmap->ref_reloc_sym->name);
+		if (kallsyms__get_function_start(kallsyms_filename,
+						 kmap->ref_reloc_sym->name, &start))
+			return -ENOENT;
 		if (start != kmap->ref_reloc_sym->addr)
 			return -EINVAL;
 	}
@@ -1248,9 +1249,7 @@ static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
 	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
 		return 0;
 
-	addr = kallsyms__get_function_start(filename,
-					    kmap->ref_reloc_sym->name);
-	if (!addr)
+	if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
 		return -1;
 
 	*delta = addr - kmap->ref_reloc_sym->addr;