From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756807AbcDGTMk (ORCPT ); Thu, 7 Apr 2016 15:12:40 -0400 Received: from mx2.suse.de ([195.135.220.15]:51648 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751802AbcDGTMj (ORCPT ); Thu, 7 Apr 2016 15:12:39 -0400 Date: Thu, 7 Apr 2016 21:12:36 +0200 From: "Luis R. Rodriguez" To: Daniel Kiper Cc: "Luis R. Rodriguez" , Andrew Cooper , Boris Ostrovsky , david.vrabel@citrix.com, Roger Pau =?iso-8859-1?Q?Monn=E9?= , Matt Fleming , Juergen Gross , Charles Arndol , Jim Fehlig , Jan Beulich , "H. Peter Anvin" , x86@kernel.org, Gary Lin , Andy Lutomirski , Stefano Stabellini , Julien Grall , Borislav Petkov , joeyli , Jeffrey Cheung , Michael Chang , =?utf-8?Q?Vojt=C4=9Bch_Pavl=C3=ADk?= , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, Jeff Mahoney Subject: Re: HVMLite / PVHv2 - using x86 EFI boot entry Message-ID: <20160407191236.GN1990@wotan.suse.de> References: <20160406024027.GX1990@wotan.suse.de> <20160406111130.GG3489@olila.local.net-space.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160406111130.GG3489@olila.local.net-space.pl> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 06, 2016 at 01:11:30PM +0200, Daniel Kiper wrote: > On Wed, Apr 06, 2016 at 04:40:27AM +0200, Luis R. Rodriguez wrote: > > Boris sent out the first HVMLite series of patches to add a new Xen guest type > > February 1, 2016 [0]. We've been talking off list with a few folks now over > > the prospect of instead of adding yet-another-boot-entry we instead fixate > > HVMLite to use the x86 EFI boot entry. There's a series of reasons to consider > > this, likewise there are reasons to question the effort required and if its > > really needed. We'd like some more public review of this proposal, and see if > > others can come up with other ideas, both in favor or against this proposal. > > > > This in particular is also a good time to get x86 Linux folks to chime on on > > the general design proposal of HVMLite design, given that outside of the boot > > entry discussion it would seem including myself that we didn't get the memo > > over the proposed architecture review [1]. At least on my behalf perhaps the > > only sticking thorns of the design was the new boot entry, which came to me > > as a surprise, and this thread addresses and the lack of addressing semantics > > for early boot (which we may seem to need to address; some of this is being > > addressing in parallels through other work). The HVMLite document talks about > > using ACPI_FADT_NO_VGA -- we don't use this yet upstream but I have some pending > > changes which should make it easy to integrate its use on HVMLite. Perhaps > > there are others that may have some other points they may want to raise now... > > > > A huge summary of the discussion over EFI boot option for HVMLite is now on a > > wiki [2], below I'll just provide the outline of the discussion. Consider this a > > request for more public review, feel free to take any of the items below and > > elaborate on it as you see fit. > > > > Worth mentioning also is that this topic will be discussed at the 2016 Xen > > Hackathon April 18-19 [3] at the ARM Cambridge, UK Headquarters so if you can > > attend and this topic interests you, consider attending. > > I hope that you will be there as one of the biggest proponents of EFI entry point. It would be a last minute trip to prepare for... > If you does not it will be difficult or impossible to discuss this issue without you. > In the worst case I can raise this topic on behalf of you and then we should organize > phone call if possible (and accepted by others). However, to do that I must know your > plans in advance. I understand, I'd like to make it clear I am taking simply a neutral position on this topic, even though it may seem I'm a die-hard on this idea, this was simply an architectural question that came up, and I have been just dissatisfied with the answers against the architectural questions I had over this. To help better evaluate how neutral really a discussion like this can be can someone please help chime in on the question of if there are pressures to just complete HVMLite design already ? How strong are those ? Are we really able to have a very neutral technical discussion on this ? Luis