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Date: Mon, 12 Mar 2007 17:46:00 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Michal Schmidt <mschmidt@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
       linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH -rt] fix preempt count underflow in user_trace_stop
Message-ID: <20070312164600.GA25139@elte.hu>
References: <45F579D9.7090307@redhat.com>
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* Michal Schmidt <mschmidt@redhat.com> wrote:

> When playing with trace_user_trigger_irq in order to trace 
> IRQ->userspace latencies, I encountered a bug in the latency tracer. 
> If I have wakeup_timing enabled and attempt to stop the trace in my 
> userspace program, the system crashes. This is caused by an unbalanced 
> preempt_enable() which underflows the preempt count.

good catch! I've applied it,

	Ingo