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Subject: Re: deadlock in synchronize_srcu() in debugfs?
From: Johannes Berg <johannes@sipsolutions.net>
To: paulmck@linux.vnet.ibm.com
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
        Nicolai Stange <nicstange@gmail.com>,
        gregkh <gregkh@linuxfoundation.org>
Date: Thu, 23 Mar 2017 16:46:37 +0100
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On Thu, 2017-03-23 at 08:37 -0700, Paul E. McKenney wrote:

> I have not seen this, but my usual question for __synchronize_srcu()
> is if some other task is blocked holding srcu_read_lock() for that
> same srcu_struct.
> 

Not as far as I can see - but that was the scenario I was outlining in
my second email, I guess.

I'll need to reproduce it and a get a fuller view of the system, I only
have the "echo w > sysrq-trigger" output right now.

Thanks,
johannes