diff --git a/[refs] b/[refs]
index e40a599e455c..26b3b893cd92 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 54f7be5b831254199522523ccab4c3d954bbf576
+refs/heads/master: 9366c1ba13fbc41bdb57702e75ca4382f209c82f
diff --git a/trunk/kernel/trace/ring_buffer.c b/trunk/kernel/trace/ring_buffer.c
index ec01803e0a55..4cb5e5147165 100644
--- a/trunk/kernel/trace/ring_buffer.c
+++ b/trunk/kernel/trace/ring_buffer.c
@@ -3783,12 +3783,17 @@ void
 ring_buffer_read_finish(struct ring_buffer_iter *iter)
 {
 	struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer;
+	unsigned long flags;
 
 	/*
 	 * Ring buffer is disabled from recording, here's a good place
-	 * to check the integrity of the ring buffer. 
+	 * to check the integrity of the ring buffer.
+	 * Must prevent readers from trying to read, as the check
+	 * clears the HEAD page and readers require it.
 	 */
+	raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
 	rb_check_pages(cpu_buffer);
+	raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
 
 	atomic_dec(&cpu_buffer->record_disabled);
 	atomic_dec(&cpu_buffer->buffer->resize_disabled);