From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NKHRr-00048A-4P for qemu-devel@nongnu.org; Mon, 14 Dec 2009 15:23:15 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NKHRm-00044E-FX for qemu-devel@nongnu.org; Mon, 14 Dec 2009 15:23:14 -0500 Received: from [199.232.76.173] (port=45647 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NKHRm-000444-1k for qemu-devel@nongnu.org; Mon, 14 Dec 2009 15:23:10 -0500 Received: from mx1.redhat.com ([209.132.183.28]:6818) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NKHRl-0007f4-FR for qemu-devel@nongnu.org; Mon, 14 Dec 2009 15:23:09 -0500 Date: Mon, 14 Dec 2009 22:20:20 +0200 From: "Michael S. Tsirkin" Subject: Re: [Qemu-devel] Re: qdev property bug? Message-ID: <20091214202019.GF6150@redhat.com> References: <20091214132423.GB973@redhat.com> <4B263F23.2090601@suse.de> <4B2647AF.1030605@codemonkey.ws> <20091214141143.GA1360@redhat.com> <20091214141341.GB1360@redhat.com> <4B264AF1.6060802@codemonkey.ws> <7FB8DD1225E54176BCAF5523B6AEA89B@FSCPC> <4B26931E.4000101@codemonkey.ws> <20091214194210.GB6150@redhat.com> <4B269933.3010906@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4B269933.3010906@codemonkey.ws> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: glommer@redhat.com, qemu-devel@nongnu.org, Alexander Graf , Kevin O'Connor , Gerd Hoffmann , Sebastian Herbszt On Mon, Dec 14, 2009 at 01:59:47PM -0600, Anthony Liguori wrote: > Michael S. Tsirkin wrote: >> At some level this is wrong. ROM presence is a hardware feature and you >> definitely need to select your hardware when you create a VM. For real >> hardware, cards with PXE are sometimes more expensive than without as >> they need ROM memory. People do select hardware based on this. >> >> Even when PXE is present in hardware, most BIOS >> vendors will let you turn it on/off optionally, >> for security if not for other reasons. >> >> What the default should be depends on whether the >> majority of our users use PXE. I guess not, >> and if I am right default should be off. >> > > The real way to pose this question is, what is the impact to users by > keeping this on to those that don't use it vs. the cost of turning it > off by default for users that do need it. > > So far, it's not clear to me that anyone has demonstrated how this is > harmful for people that don't want pxe booting. Assuming we fix the bug > about rom loading, then there's really no impact to users. > > Regards, > > Anthony Liguori PXE booting might have security impact. You do not want to do this if you are on a hostile network. -- MST