From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751968AbeB0UDK (ORCPT ); Tue, 27 Feb 2018 15:03:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:60608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751716AbeB0UDJ (ORCPT ); Tue, 27 Feb 2018 15:03:09 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D9A1820685 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=sstabellini@kernel.org Date: Tue, 27 Feb 2018 12:03:08 -0800 (PST) From: Stefano Stabellini X-X-Sender: sstabellini@sstabellini-ThinkPad-X260 To: Julien Grall cc: Juergen Gross , Andrii Anisov , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, boris.ostrovsky@oracle.com, Stefano Stabellini , jbeulich@suse.com Subject: Re: [Xen-devel] [PATCH] xen: use hvc console for dom0 In-Reply-To: Message-ID: References: <20180226110822.13787-1-jgross@suse.com> <0d8bdda5-faef-41da-344a-644b5c3d6006@epam.com> <58e94cc9-9b09-d6b7-3122-fb4c83e97926@suse.com> User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="8323329-1944649226-1519761789=:4239" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-1944649226-1519761789=:4239 Content-Type: TEXT/PLAIN; charset=UTF-8 Content-Transfer-Encoding: 8BIT On Tue, 27 Feb 2018, Julien Grall wrote: > Hi, > > On 26/02/18 12:32, Juergen Gross wrote: > > On 26/02/18 13:06, Andrii Anisov wrote: > > > Hello Juergen, > > > > > > > > > On 26.02.18 13:08, Juergen Gross wrote: > > > > Today the hvc console is added as a preferred console for pv domUs > > > > only. As this requires a boot parameter for getting dom0 messages per > > > > default add it for dom0, too. > > > > > > > > Signed-off-by: Juergen Gross > > > > --- > > > >   arch/x86/xen/enlighten_pv.c | 4 +++- > > > >   1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c > > > Is this something x86 specific? Could it be a generic approach? > > > > In case ARM wants something similar I guess the test for > > xen_initial_domain() should be dropped in xen_early_init(). > I am pretty sure we discussed to remove !xen_initial_domain() for Arm in the > past. But I don't remember why the patch was not sent to remove it. > > Anyway, I guess this should be fine to have hvc as a preferred console for the > initial domain as well. Usually, Dom0 has access to several physical UARTs and/or VGA, making this patch less obviously desirable. I think that for Dom0 the best behavior would be to add "hvc0" as first console rather than last console, so that if the user specified something else, this call won't interfere with it. --8323329-1944649226-1519761789=:4239--