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Date: Fri, 21 Sep 2007 14:02:21 +0200
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [RFC PATCH] Add CRC checksum for RCU lists
Message-ID: <20070921140221.000a416a@twins>
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On Thu, 20 Sep 2007 14:34:11 -0400 Steven Rostedt <rostedt@goodmis.org>
wrote:


> +static inline void rcu_crc_check(struct rcu_head *head)
> +{
> +	static int once;
> +	if (unlikely(head->crc != rcu_crc_calc(head)) && !once) {
> +		once++;
> +		printk("BUG: RCU check failed!");
> +		if (head->caller)
> +			printk(" (caller=%p)",
> +			       head->caller);

		char sym[KSYM_SYMBOL_LEN];
		sprint_symbol(sym, head->caller);
		printk(" (caller: [<%p>] %s)", head->caller, sym);

> +		printk("\n");
> +		printk("  CRC was %08lx, expected %08lx\n",
> +		       head->crc, rcu_crc_calc(head));
> +		printk("  %p %p\n",
> +		       head->next, head->func);
> +		dump_stack();
> +	}
> +}