From: Gabriele Paoloni <[email protected]> [ Upstream commit 0c588ac0ca6c22b774d9ad4a6594681fdfa57d9d ]
When __ftrace_event_enable_disable invokes the class callback to unregister the event, the return value is not reported up to the caller, hence leading to event unregister failures being silently ignored. This patch assigns the ret variable to the invocation of the event unregister callback, so that its return value is stored and reported to the caller, and it raises a warning in case of error. Link: https://lore.kernel.org/[email protected] Signed-off-by: Gabriele Paoloni <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- kernel/trace/trace_events.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 94bb5f9251b13..ed0d0c8a2b4bb 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -776,7 +776,9 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); } - call->class->reg(call, TRACE_REG_UNREGISTER, file); + ret = call->class->reg(call, TRACE_REG_UNREGISTER, file); + + WARN_ON_ONCE(ret); } /* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */ if (file->flags & EVENT_FILE_FL_SOFT_MODE) -- 2.39.5
