From: Li Zefan 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 LKML-Reference: <4A9214E3.2070807@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- 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 11ba5bb..55a25c9 100644 --- a/kernel/trace/trace_event_profile.c +++ b/kernel/trace/trace_event_profile.c @@ -5,6 +5,7 @@ * */ +#include #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; } } -- 1.6.3.3 -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/