From: Chunyu Hu <chuhu@xxxxxxxxxx> This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 854145e0a8e9a05f7366d240e2f99d9c1ca6d6dd ] Currently register functions for events will be called through the 'reg' field of event class directly without any check when seting up triggers. Triggers for events that don't support register through debug fs (events under events/ftrace are for trace-cmd to read event format, and most of them don't have a register function except events/ftrace/functionx) can't be enabled at all, and an oops will be hit when setting up trigger for those events, so just not creating them is an easy way to avoid the oops. Link: http://lkml.kernel.org/r/1462275274-3911-1-git-send-email-chuhu@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx # 3.14+ Fixes: 85f2b08268c01 ("tracing: Add basic event trigger framework") Signed-off-by: Chunyu Hu <chuhu@xxxxxxxxxx> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- kernel/trace/trace_events.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index f69ec12..6459f77 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1626,8 +1626,13 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file) trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); - trace_create_file("trigger", 0644, file->dir, file, - &event_trigger_fops); + /* + * Only event directories that can be enabled should have + * triggers. + */ + if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) + trace_create_file("trigger", 0644, file->dir, file, + &event_trigger_fops); trace_create_file("format", 0444, file->dir, call, &ftrace_event_format_fops); -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html