Forwarded: Re: test patch

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Subject: Re: test patch
Author: tahasami8@gmail.com

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 9c03a555a6ba..98130182e05d 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -7995,8 +7995,10 @@ int ring_buffer_map_get_reader(struct trace_buffer *buffer, int cpu)
 		goto out;
 
 	reader = rb_get_reader_page(cpu_buffer);
-	if (WARN_ON(!reader))
+	if (!reader) {
+		WARN_ON(cpu_buffer->reader_page != cpu_buffer->commit_page);
 		goto out;
+	}
 
 	/* Check if any events were dropped */
 	missed_events = cpu_buffer->lost_events;