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From: Oliver Neukum <oliver@neukum.name>
To: nataraja kumar <hainattu@yahoo.com>, linux-kernel@vger.kernel.org
Subject: Re: A question on kernel stack
Date: Fri, 21 Feb 2003 19:09:41 +0100
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Am Freitag, 21. Februar 2003 19:05 schrieb nataraja kumar:
> hi,
> my apologies if i am wrong. please let me know
> why does kernel use kernel stack when process jumps
> from user mode to kernel mode. why can't user stack
> be used ?

Security. We can't trust user mode to pass a valid stack pointer.

	Oliver

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