From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1751976AbcEAN0Z (ORCPT <rfc822;w@1wt.eu>);
	Sun, 1 May 2016 09:26:25 -0400
Received: from mail-wm0-f48.google.com ([74.125.82.48]:36229 "EHLO
	mail-wm0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751098AbcEAN0X (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Sun, 1 May 2016 09:26:23 -0400
Date: Sun, 1 May 2016 14:26:20 +0100
From: Matt Fleming <matt@codeblueprint.co.uk>
To: Shannon Zhao <shannon.zhao@linaro.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Stefano Stabellini <sstabellini@kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        "Luis R. Rodriguez" <mcgrof@kernel.org>,
        Jeremy Fitzhardinge <jeremy@goop.org>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
        Xen Devel <Xen-devel@lists.xensource.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>, linux-next@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@alien8.de>
Subject: Re: efi_enabled(EFI_PARAVIRT) use
Message-ID: <20160501132620.GT2839@codeblueprint.co.uk>
References: <20160429142020.4499e185@canb.auug.org.au>
 <20160429063936.GA28320@gmail.com>
 <alpine.DEB.2.10.1604291123260.3312@sstabellini-ThinkPad-X260>
 <20160429143931.GG2839@codeblueprint.co.uk>
 <CAKv+Gu_k45_r0mke6ELb3Pi05BnJiEMqweJRfsy7S55FzCpF7Q@mail.gmail.com>
 <5724BDD2.5020600@linaro.org>
 <20160430204420.GM2839@codeblueprint.co.uk>
 <572576E2.7060508@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <572576E2.7060508@linaro.org>
User-Agent: Mutt/1.5.24+41 (02bc14ed1569) (2015-08-30)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Sun, 01 May, at 11:24:18AM, Shannon Zhao wrote:
> Because the UEFI params for Dom0 are located under /hypervisor/uefi node
> instead of /chosen. So it needs to check whether it's a Dom0 then search
> and parse different node with different params arrays.
 
Why can't you search both nodes? Would you ever expect to see both for
a Dom0 kernel?

> So it still needs add another check to firstly parse the fdt to see if
> there is "xen,uefi-system-table" under /hypervisor/uefi node, right? I
> think it's a bit redundant compared with xen_initial_domain().

Sometimes you really do need to check xen_initial_domain(), but I do
not think this is such a case. And if we can get by without adding
that check, the code will be better for it.