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Date: Tue, 30 Jun 2009 16:14:36 +0800
From: Lai Jiangshan <laijs@cn.fujitsu.com>
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To: Frederic Weisbecker <fweisbec@gmail.com>
CC: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>
Subject: [QUESTION] trace_function_graph: consumed event may be invalid
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In get_return_for_leaf() {
	......
	ring_buffer_consume()
	......
	access to @curr->ent.pid
}

@curr is saved at consumed event, if this event is the last event
in the page, the ring_buffer may reuse the page. It will become invalid.

Is there any other code to ensure it valid when we `cat trace_pipe`?

Lai.