diff options
| author | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-12-13 17:24:29 -0500 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-12-14 08:50:56 -0500 |
| commit | fb9f5ee9bf5cf7ebc8731a7033e57d98832dc650 (patch) | |
| tree | dd1c4a145db38e938f2c5616d7f06d6539cb35c8 /kernel/trace | |
| parent | fab89a09c86f948adfc7e20a7d608bd9f323bbe1 (diff) | |
tracing: Do not synchronize freeing of trigger filter on boot up
If a trigger filter on the kernel command line fails to apply (due to
syntax error), it will be freed. The freeing will call
tracepoint_synchronize_unregister(), but this is not needed during early
boot up, and will even trigger a lockdep splat.
Avoid calling the synchronization function when system_state is
SYSTEM_BOOTING.
Link: https://lore.kernel.org/linux-trace-kernel/20221213172429.7774f4ba@gandalf.local.home
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_events_trigger.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index 19ce9d22bfd7..e535959939d3 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1085,8 +1085,14 @@ int set_trigger_filter(char *filter_str, rcu_assign_pointer(data->filter, filter); if (tmp) { - /* Make sure the call is done with the filter */ - tracepoint_synchronize_unregister(); + /* + * Make sure the call is done with the filter. + * It is possible that a filter could fail at boot up, + * and then this path will be called. Avoid the synchronization + * in that case. + */ + if (system_state != SYSTEM_BOOTING) + tracepoint_synchronize_unregister(); free_event_filter(tmp); } |