From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756313AbYBYGUj (ORCPT ); Mon, 25 Feb 2008 01:20:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752958AbYBYGUb (ORCPT ); Mon, 25 Feb 2008 01:20:31 -0500 Received: from e1.ny.us.ibm.com ([32.97.182.141]:35080 "EHLO e1.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752679AbYBYGUa (ORCPT ); Mon, 25 Feb 2008 01:20:30 -0500 Subject: Re: [RFC] [PATCH] To refuse users from probing preempt_schedule() From: Dave Hansen To: srinivasa Cc: linux-kernel@vger.kernel.org, Andrew Morton , ananth@in.ibm.com, Jim Keniston , srikar@linux.vnet.ibm.com In-Reply-To: <200802251127.40579.srinivasa@in.ibm.com> References: <200802251127.40579.srinivasa@in.ibm.com> Content-Type: text/plain Date: Sun, 24 Feb 2008 22:20:24 -0800 Message-Id: <1203920424.6662.14.camel@nimitz.home.sr71.net> Mime-Version: 1.0 X-Mailer: Evolution 2.12.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2008-02-25 at 11:27 +0530, srinivasa wrote: > This patch prohibits user from probing preempt_schedule(). One way of > prohibiting the user from probing functions is by marking such > functions with __kprobes. But this method doesn't work for those functions, > which are already marked to different section like preempt_schedule() > (belongs to __sched section). So we use blacklist approach to refuse user > from probing these functions. preempt_schedule() does sound really, really important. But, what kinds of functions can't be kprobed? It would be nice to give that blacklist a nice comment on the topic. :) Also, have you strained your brains to think of other functions that this should be applied to? Is it just for functions that are sensitive and already have an assigned section? Might be nice to call that out explicitly. -- Dave