diff options
| author | Li Zefan <lizf@cn.fujitsu.com> | 2009-08-24 12:19:47 +0800 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2009-09-12 22:28:38 -0400 |
| commit | 558e6547e4b8a2b13608a24a9d3679802f91c4c7 (patch) | |
| tree | aa7eeeee57fbf93d2ff3811a362ffef19be17c29 | |
| parent | 4818d80942b7c0021d213b7c5f1a14a832820a01 (diff) | |
tracing/profile: fix profile_disable vs module_unload
If the correspoding module is unloaded before ftrace_profile_disable()
is called, event->profile_disable() won't be called, which can
cause oops:
# insmod trace-events-sample.ko
# perf record -f -a -e sample:foo_bar sleep 3 &
# sleep 1
# rmmod trace_events_sample
# insmod trace-events-sample.ko
OOPS!
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A9214E3.2070807@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/trace_event_profile.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c index 11ba5bb4ed0..55a25c933d1 100644 --- a/kernel/trace/trace_event_profile.c +++ b/kernel/trace/trace_event_profile.c @@ -5,6 +5,7 @@ * */ +#include <linux/module.h> #include "trace.h" int ftrace_profile_enable(int event_id) @@ -14,7 +15,8 @@ int ftrace_profile_enable(int event_id) mutex_lock(&event_mutex); list_for_each_entry(event, &ftrace_events, list) { - if (event->id == event_id && event->profile_enable) { + if (event->id == event_id && event->profile_enable && + try_module_get(event->mod)) { ret = event->profile_enable(event); break; } @@ -32,6 +34,7 @@ void ftrace_profile_disable(int event_id) list_for_each_entry(event, &ftrace_events, list) { if (event->id == event_id) { event->profile_disable(event); + module_put(event->mod); break; } } |