Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755521AbcDMTOL (ORCPT ); Wed, 13 Apr 2016 15:14:11 -0400 Received: from mx2.suse.de ([195.135.220.15]:35218 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751406AbcDMTOJ (ORCPT ); Wed, 13 Apr 2016 15:14:09 -0400 Date: Wed, 13 Apr 2016 21:14:08 +0200 From: "Luis R. Rodriguez" To: Konrad Rzeszutek Wilk Cc: "Luis R. Rodriguez" , Roger Pau =?iso-8859-1?Q?Monn=E9?= , Matt Fleming , jeffm@suse.com, Michael Chang , Linux Kernel Mailing List , Jim Fehlig , Jan Beulich , "H. Peter Anvin" , Daniel Kiper , the arch/x86 maintainers , Takashi Iwai , =?utf-8?Q?Vojt=C4=9Bch_Pavl=C3=ADk?= , Gary Lin , xen-devel , Jeffrey Cheung , Juergen Gross , Stefano Stabellini , Julien Grall , George Dunlap , joeyli , Borislav Petkov , Boris Ostrovsky , Charles Arndol , Andrew Cooper , Julien Grall , Andy Lutomirski , David Vrabel , torvalds@linux-foundation.org Subject: Re: [Xen-devel] HVMLite / PVHv2 - using x86 EFI boot entry Message-ID: <20160413191408.GA1990@wotan.suse.de> References: <20160406024027.GX1990@wotan.suse.de> <20160407185148.GL1990@wotan.suse.de> <5707BD2E.20204@citrix.com> <20160408215854.GU1990@wotan.suse.de> <20160413095428.5mcbrimvc6vxffcw@mac> <20160413185010.GX1990@wotan.suse.de> <20160413190226.GB7501@char.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20160413190226.GB7501@char.us.oracle.com> 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 Content-Length: 2373 Lines: 51 On Wed, Apr 13, 2016 at 03:02:26PM -0400, Konrad Rzeszutek Wilk wrote: > On Wed, Apr 13, 2016 at 08:50:10PM +0200, Luis R. Rodriguez wrote: > > On Wed, Apr 13, 2016 at 11:54:29AM +0200, Roger Pau Monn? wrote: > > > On Fri, Apr 08, 2016 at 11:58:54PM +0200, Luis R. Rodriguez wrote: > > > > OK thanks for the clarification -- still no custom entries for Xen! > > > > We should strive for that, at the very least. > > > > > > > > You do have a point about the legacy stuff. There are two options there: > > > > > > > > * Fold legacy support under HVMLite -- which seems to be what we > > > > currently want to do (we should evaluate the implications and > > > > requirements here for that); or > > > > > > I'm not following here. What does it mean to fold legacy support under > > > HVMlite? HVMlite doesn't have any legacy hardware, and that's the issue when > > > it comes to using native Linux entry points. Linux might expect some legacy > > > PC hardware to be always present, which is not true for HVMlite. > > > > > > Could you please clarify this point? > > > > It seems there is a confusion on terms used. By folding legacy support under > > HVMLite I meant folding legacy PV path (classic PV with PV interfaces) under > > HVMlite. > > Ewww. Probably a confusion again on terms, by the above I meant to say what you seem to be indicating below, which is to keep old PV guest support with PV interfaces using a new shiny entry. Or are we really going to nuke full support for old PV guests ? > > I got the impression that if we wanted to remove the old PV path we had to see > > if we can address old classic PV x86 guests through HVMlite, otherwise we'd > > have to live with the old PV path for the long term. > > No. We need to deprecate the PV paths - and the agreement we hammered out > with the x86 maintainers was that once PVH/HVMLite is stable the clock > would start ticking on PV (pvops) life. All the big users of PV Linux > were told in persons to prep them for this. That's nice. *How* that is done is what we are determining here. > Keep in mind that this is not for deleting of support in hypervisor for > PV hypercalls - meaning you would still be able to run say 2.6.18 RHEL5 > in years to come. It is just that Linux v6.1 won't have any more PV paths > and can only run in HVM or PVH/HVMLite mode under Xen. Sure. Luis