Date: Wed, 13 Apr 2016 20:54:51 +0200
From: "Luis R. Rodriguez" <mcgrof@kernel.org>
To: George Dunlap <george.dunlap@citrix.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>,
        Matt Fleming <matt@codeblueprint.co.uk>, jeffm@suse.com,
        Michael Chang <MChang@suse.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Jim Fehlig <jfehlig@suse.com>, Jan Beulich <JBeulich@suse.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Daniel Kiper <daniel.kiper@oracle.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        Takashi Iwai <tiwai@suse.de>,
        =?utf-8?Q?Vojt=C4=9Bch_Pavl=C3=ADk?= <vojtech@suse.cz>,
        Gary Lin <GLin@suse.com>, xen-devel <xen-devel@lists.xenproject.org>,
        Jeffrey Cheung <JCheung@suse.com>, Juergen Gross <jgross@suse.com>,
        Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
        Julien Grall <julien.grall@linaro.org>, joeyli <jlee@suse.com>,
        Borislav Petkov <bp@alien8.de>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Charles Arndol <carnold@suse.com>,
        Andrew Cooper <andrew.cooper3@citrix.com>,
        Julien Grall <julien.grall@arm.com>,
        Andy Lutomirski <luto@amacapital.net>,
        David Vrabel <david.vrabel@citrix.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Roger Pau =?iso-8859-1?Q?Monn=E9?= <roger.pau@citrix.com>
Subject: Re: [Xen-devel] HVMLite / PVHv2 - using x86 EFI boot entry
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On Wed, Apr 13, 2016 at 11:05:00AM +0100, George Dunlap wrote:
> On Tue, Apr 12, 2016 at 11:12 PM, Luis R. Rodriguez <mcgrof@kernel.org> wrote:
> > Also, x86 does have a history of short DT use. Just pointing that its there as
> > an option as well. I'll Cc you on some thread about that.
> 
> I'm not sure how this is relevant to anything.

You brought DT as a reason why ARM was able to use the native point.
I'm clarifying DT has nothing to do as a restriction on x86.

> What we're talking about is how to get from Xen to a point in the
> Linux kernel where everything can Just Work.  The proposed feature is
> a mini trampoline that (as I understand it):
> 1. Tells Xen where to jump to (via ELF note)
> 2. Sets up some basic modes and pagetables and then jumps to the zero
> page so Linux can just carry on.

Right, and the my goal is to see to it we do enough homework to
ensure we reviewed all possibilities to share as much code as possible
already and looked at all options before saying we certainly need yet
another entry point. I am not convinced yet this has been done.

  Luis