From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751964AbeB0UJN (ORCPT ); Tue, 27 Feb 2018 15:09:13 -0500 Received: from mail-ve1eur01on0071.outbound.protection.outlook.com ([104.47.1.71]:18559 "EHLO EUR01-VE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751533AbeB0UJL (ORCPT ); Tue, 27 Feb 2018 15:09:11 -0500 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=Julien.Grall@arm.com; Cc: nd@arm.com, Juergen Gross , Andrii Anisov , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, boris.ostrovsky@oracle.com, jbeulich@suse.com Subject: Re: [Xen-devel] [PATCH] xen: use hvc console for dom0 To: Stefano Stabellini References: <20180226110822.13787-1-jgross@suse.com> <0d8bdda5-faef-41da-344a-644b5c3d6006@epam.com> <58e94cc9-9b09-d6b7-3122-fb4c83e97926@suse.com> From: Julien Grall Message-ID: <19afb9f9-a845-e627-8f78-d1fdb349c6bd@arm.com> Date: Tue, 27 Feb 2018 20:09:05 +0000 User-Agent: Mozilla/5.0 (Macintosh; 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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. Well, that's exactly the goal of add_preferred_console. It will use hvc0 unless specified otherwise by the user on the command line. Cheers, -- Julien Grall