Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751685AbbLIPX2 (ORCPT ); Wed, 9 Dec 2015 10:23:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56211 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751350AbbLIPX0 (ORCPT ); Wed, 9 Dec 2015 10:23:26 -0500 From: Vitaly Kuznetsov To: Sander Eikelenboom Cc: Jan Beulich , Boris Ostrovsky , David Vrabel , x86@kernel.org, tglx@linutronix.de, xen-devel@lists.xenproject.org, mingo@redhat.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org, hpa@zytor.com Subject: Re: [Xen-devel] [PATCH] x86: Xen PV guests don't have the rtc_cmos platform device References: <1449671569-4540-1-git-send-email-boris.ostrovsky@oracle.com> <56684BD402000078000BDB00@prv-mh.provo.novell.com> <745827c24ef5e59808d725d5777b5698@eikelenboom.it> Date: Wed, 09 Dec 2015 16:23:21 +0100 In-Reply-To: <745827c24ef5e59808d725d5777b5698@eikelenboom.it> (Sander Eikelenboom's message of "Wed, 09 Dec 2015 16:00:21 +0100") Message-ID: <87si3b1w9i.fsf@vitty.brq.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1223 Lines: 39 Sander Eikelenboom writes: > On 2015-12-09 15:42, Jan Beulich wrote: >>>>> On 09.12.15 at 15:32, wrote: >>> --- a/arch/x86/kernel/rtc.c >>> +++ b/arch/x86/kernel/rtc.c >>> @@ -200,6 +200,9 @@ static __init int add_rtc_cmos(void) >>> } >>> #endif >>> >>> + if (paravirt_enabled()) >>> + return -ENODEV; >> >> What about Xen Dom0? >> >> Jan > > Checked that in my testing and that still worked: > [ 16.733837] rtc_cmos 00:02: RTC can wake from S4 > [ 16.734030] rtc_cmos 00:02: rtc core: registered rtc_cmos as rtc0 > [ 16.734087] rtc_cmos 00:02: alarms up to one month, y3k, 114 bytes > nvram > [ 17.760329] rtc_cmos 00:02: setting system clock to 2015-12-09 > 08:43:48 UTC (1449650628) > > and /dev/rtc and /dev/rtc0 both exist. > > But i don't know the nitty gritty details about why ... As far as I can see in Dom0 the device is present in ACPI as PNP0B00 so a different path is probably in use. -- Vitaly -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/