perf kmaps: Check kmaps to make code more robust
This patch add checks in places where map__kmap is used to get kmaps
from struct kmap.
Error messages are added at map__kmap to warn invalid accessing of kmap
(for the case of !map->dso->kernel, kmap(map) does not exists at all).
Also, introduces map__kmaps() to warn uninitialized kmaps.
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1428394966-131044-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index e45c8f3..9c380a2 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -679,6 +679,9 @@
machine->vmlinux_maps[type]->unmap_ip =
identity__map_ip;
kmap = map__kmap(machine->vmlinux_maps[type]);
+ if (!kmap)
+ return -1;
+
kmap->kmaps = &machine->kmaps;
map_groups__insert(&machine->kmaps,
machine->vmlinux_maps[type]);
@@ -700,7 +703,7 @@
kmap = map__kmap(machine->vmlinux_maps[type]);
map_groups__remove(&machine->kmaps,
machine->vmlinux_maps[type]);
- if (kmap->ref_reloc_sym) {
+ if (kmap && kmap->ref_reloc_sym) {
/*
* ref_reloc_sym is shared among all maps, so free just
* on one of them.