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To: Adam Litke <agl@us.ibm.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [RFC] Smarter stack traces using the frame pointer
From: Andi Kleen <ak@muc.de>
Date: Mon, 10 Nov 2003 19:06:03 +0100
In-Reply-To: <QouH.36G.7@gated-at.bofh.it> (Adam Litke's message of "Mon, 10
 Nov 2003 19:00:15 +0100")
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Adam Litke <agl@us.ibm.com> writes:

> -static int kstack_depth_to_print = 24;
> +static int kstack_depth_to_print = 128;

I would not do that. It makes too much of the oops scroll away.

> +	show_stack_frame((unsigned long) stack, ebp+4);

I think this needs much more sanity checking, otherwise the risk
of recursive oops etc is too big.

I would always check first if the stack value read from ebp is inside the 
stack page of the current process. If you're paranoid you could even use 
__get_user() to catch exceptions.

-Andi