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Date: Fri, 18 Jan 2008 16:15:14 +0100
From: llandre <r&d2@dave-tech.it>
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To: linux-kernel@vger.kernel.org
Subject: Kernel 2.6.22.6 hangs in synchronize_rcu
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I'm porting kernel 2.6.22.6 on custom embedded system (ARM1136).
During network subsystem initialization, kernel hangs in function 
synchronize_rcu invoked by synchronize_net. In particular
wait_for_completion(&rcu.completion);
never returns and wakeme_after_rcu is never hit.
Anybody can give me any advice about how to investigate this issue?

void synchronize_rcu(void)
{
     struct rcu_synchronize rcu;

     init_completion(&rcu.completion);
     /* Will wake me after RCU finished */
     call_rcu(&rcu.head, wakeme_after_rcu);

     /* Wait for it */
     wait_for_completion(&rcu.completion);
}


Thanks in advance,
llandre

DAVE Electronics System House - R&D Department
web:   http://www.dave-tech.it
email: r&d2@dave-tech.it