Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267876AbUIUR2W (ORCPT ); Tue, 21 Sep 2004 13:28:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267890AbUIUR2W (ORCPT ); Tue, 21 Sep 2004 13:28:22 -0400 Received: from [69.25.196.29] ([69.25.196.29]:46737 "EHLO thunker.thunk.org") by vger.kernel.org with ESMTP id S267876AbUIUR2H (ORCPT ); Tue, 21 Sep 2004 13:28:07 -0400 Date: Tue, 21 Sep 2004 13:25:46 -0400 From: "Theodore Ts'o" To: Alex Williamson Cc: "Yu, Luming" , Dmitry Torokhov , acpi-devel@lists.sourceforge.net, "Keshavamurthy, Anil S" , "Brown, Len" , LHNS list , Linux IA64 , Linux Kernel Subject: Re: [ACPI] PATCH-ACPI based CPU hotplug[2/6]-ACPI Eject interfacesupport Message-ID: <20040921172546.GA7077@thunk.org> Mail-Followup-To: Theodore Ts'o , Alex Williamson , "Yu, Luming" , Dmitry Torokhov , acpi-devel@lists.sourceforge.net, "Keshavamurthy, Anil S" , "Brown, Len" , LHNS list , Linux IA64 , Linux Kernel References: <3ACA40606221794F80A5670F0AF15F84059309EF@pdsmsx403> <1095735738.3920.29.camel@mythbox> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1095735738.3920.29.camel@mythbox> User-Agent: Mutt/1.5.6+20040818i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1390 Lines: 28 On Mon, Sep 20, 2004 at 09:02:18PM -0600, Alex Williamson wrote: > > But, some AML methods are risky to be called directly from user space, > > Not only because the side effect of its execution, but also because > > it could trigger potential AML method bug or interpreter bug, or even > > architectural defect. All of these headache is due to the AML method > > is NOT intended for being used by userspace program. > > I've made an attempt to hide the most obvious dangerous methods, but > undoubtedly, there will be some. Why are we any more likely to hit an > AML method bug, interpreter bug or architectural bug by having a > userspace interface? As long as the userspace interfaces are only available to the root filesystem, I'm not sure it's worth it to hide any of the methods. It's added complexity, and in any case, root can do untold amounts of damage by writing to /dev/mem, trying to upload firmware to IDE drives, etc., etc., etc. As you have pointed out, if there are bugs in the interpret, et. al, it is better to expose them sooner rather than to stick our heads in the sand and pretend they don't exist. - Ted - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/