[PATCH 2/2] perf symbols: Load map before using map->map_ip()

From: Arnaldo Carvalho de Melo
Date: Thu Jan 23 2014 - 14:38:49 EST

From: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>

In map_groups__find_symbol() map->map_ip is used without ensuring the
map is loaded. Then the address passed to map->map_ip isn't mapped at
the first time.

E.g. below code always fails to get a symbol at the first call;

addr = /* Somewhere in the kernel text */
symbol_conf.try_vmlinux_path = true;
host_machine = machine__new_host();
sym = machine__find_kernel_function(host_machine,
addr, NULL, NULL);
/* Note that machine__find_kernel_function calls
map_groups__find_symbol */

This ensures it by calling map__load before using it in

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: "David A. Long" <dave.long@xxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Cc: "Steven Rostedt (Red Hat)" <rostedt@xxxxxxxxxxx>
Cc: yrl.pp-manager.tt@xxxxxxxxxxx
Link: http://lkml.kernel.org/r/20140123022950.7206.17357.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
tools/perf/util/map.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index ee1dd687a262..3b97513f0e77 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -386,7 +386,8 @@ struct symbol *map_groups__find_symbol(struct map_groups *mg,
struct map *map = map_groups__find(mg, type, addr);

- if (map != NULL) {
+ /* Ensure map is loaded before using map->map_ip */
+ if (map != NULL && map__load(map, filter) >= 0) {
if (mapp != NULL)
*mapp = map;
return map__find_symbol(map, map->map_ip(map, addr), filter);

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