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Date: Tue, 4 Nov 2008 03:03:27 +0100
From: "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" <fweisbec@gmail.com>
To: "Ingo Molnar" <mingo@elte.hu>
Subject: Re: [PATCH] tracing: use raw spinlocks instead of spinlocks
Cc: "Steven Rostedt" <rostedt@goodmis.org>,
       "Linux Kernel" <linux-kernel@vger.kernel.org>
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2008/11/3 Ingo Molnar <mingo@elte.hu>:
> Frederic, do you have trouble finding the source of the deadlock? In
> theory the NMI watchdog should be able to punch through it. (if not
> then we need to improve things so that it can)

Ok...actually I still have a deadlock. Or it seems to. I launch the
return tracer and then...the system
can block after several seconds, typically after I try to write some
characters on the terminal.

It happens more easily on SMP.

I enabled all I could for lock debugging, but I don't have any errors printed...
Lockdep uses an NMI wachdog?