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Date: Thu, 21 May 2009 21:53:30 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org
Subject: fork() && ftrace_graph_exit_task()
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What if the task with ->ret_stack != NULL calls fork(), and
copy_prcoess() fails after successfull dup_task_struct() ?

bad_fork_free: -> free_task()->ftrace_graph_exit_task() will
free the parent's ->ret_stack copied by arch_dup_task_struct(),
no?

Oleg.