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Date: Thu, 28 May 2009 14:22:17 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Paul Mundt <lethal@linux-sh.org>
cc: Peter Zijlstra <peterz@infradead.org>, Daniel Walker <dwalker@fifo99.com>,
       Linus Walleij <linus.ml.walleij@gmail.com>, Ingo Molnar <mingo@elte.hu>,
       Andrew Victor <linux@maxim.org.za>,
       Haavard Skinnemoen <hskinnemoen@atmel.com>,
       Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org,
       linux-sh@vger.kernel.org, linux-arm-kernel@lists.arm.linux.org.uk,
       John Stultz <johnstul@linux.vnet.ibm.com>
Subject: Re: [PATCH] sched: Support current clocksource handling in fallback
 sched_clock().
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On Thu, 28 May 2009, Paul Mundt wrote:
> @@ -437,10 +441,19 @@ void clocksource_unregister(struct clocksource *cs)
>  	unsigned long flags;
>  
>  	spin_lock_irqsave(&clocksource_lock, flags);
> +
> +	if (sched_clocksource == cs) {
> +		printk(KERN_WARNING "Refusing to unregister "
> +		       "scheduler clocksource %s", cs->name);

  Hmm, isn't that dangerous ? The clocksource might be in a module or
  in kmalloced memory which is going to be freed.

Thanks,

	tglx