ring-buffer: do not reset while in a commit

The callers of reset must ensure that no commit can be taking place
at the time of the reset. If it does then we may corrupt the ring buffer.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index da2c59d8f486..79d6012bb1f1 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -3373,12 +3373,16 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu)
 
         spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
 
+        if (RB_WARN_ON(cpu_buffer, local_read(&cpu_buffer->committing)))
+                goto out;
+
         __raw_spin_lock(&cpu_buffer->lock);
 
         rb_reset_cpu(cpu_buffer);
 
         __raw_spin_unlock(&cpu_buffer->lock);
 
+ out:
         spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
 
         atomic_dec(&cpu_buffer->record_disabled);