From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Egger Subject: Re: Allow tools to see the hypervisor command line. Date: Wed, 17 Jun 2009 18:08:49 +0200 Message-ID: <200906171808.50151.Christoph.Egger@amd.com> References: <1245252745.5862.145.camel@zakaz.uk.xensource.com> <200906171742.13899.Christoph.Egger@amd.com> <1245253781.5862.150.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1245253781.5862.150.camel@zakaz.uk.xensource.com> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Ian Campbell Cc: "xen-devel@lists.xensource.com" , Keir Fraser List-Id: xen-devel@lists.xenproject.org On Wednesday 17 June 2009 17:49:41 Ian Campbell wrote: > On Wed, 2009-06-17 at 11:42 -0400, Christoph Egger wrote: > > On Wednesday 17 June 2009 17:32:25 Ian Campbell wrote: > > > This is useful from tools in the same way /proc/cmdline is useful for > > > the domain 0 kernel. > > > > On NetBSD Dom0, this is sysctl machdep.booted_kernel. > > Current implementation doesn't work properly, since Xen throws away > > the first argument at startup. > > Is it possible to not kill it ? > > You mean "module /boot/netsd foo=bar baz=1" becomes just "foo=bar baz=1" > on the command line which the kernel sees but on native netbsd it would > be "/boot/netsd foo=bar baz=1"? Correct. On NetBSD, the system tools accessing kernel virtual space need the kernel name to find the correct one since the kernel can be anywere and can have any name (though there's a default name and default place). You can also place the linux kernel anywhere and have any name for it. GRUB doesn't care about it, right ? (Though there's a default name and a default place as well) > This patch wouldn't make any difference > to that (I guess you are just bringing it up as an aside). I supposed so. > Changing Xen's behaviour here would be interesting -- Linux for example > doesn't expect to get the extra element on the command line, not sure > what it would do with it, similarly for other existing dom0 guests. It > would also be inconsistent with how PV domU's are launched. I suppose, Xen throws the first argument away for historical reasons with the assumption that noone needs it because Linux has no use for it. Christoph -- ---to satisfy European Law for business letters: Advanced Micro Devices GmbH Karl-Hammerschmidt-Str. 34, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Thomas M. McCoy, Giuliano Meroni Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632