From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754535Ab3ENQZV (ORCPT ); Tue, 14 May 2013 12:25:21 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:17312 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751194Ab3ENQZU convert rfc822-to-8bit (ORCPT ); Tue, 14 May 2013 12:25:20 -0400 User-Agent: K-9 Mail for Android In-Reply-To: <51926396.4040203@linaro.org> References: <1368467768-2316-1-git-send-email-david.vrabel@citrix.com> <1368467768-2316-4-git-send-email-david.vrabel@citrix.com> <51918ABB.5030501@linaro.org> <51920A9502000078000D5D84@nat28.tlf.novell.com> <51925F70.5000309@linaro.org> <51927F2002000078000D6224@nat28.tlf.novell.com> <51926396.4040203@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset=UTF-8 Subject: Re: [Xen-devel] [PATCH 3/3] x86/xen: sync the CMOS RTC as well as the Xen wallclock From: Konrad Rzeszutek Wilk Date: Tue, 14 May 2013 12:24:57 -0400 To: John Stultz , Jan Beulich CC: David Vrabel , Jeremy Fitzhardinge , Thomas Gleixner , xen-devel@lists.xen.org, linux-kernel@vger.kernel.org Message-ID: <32efe991-ac51-410b-aead-68a480e628d6@email.android.com> X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org John Stultz wrote: >On 05/14/2013 09:14 AM, Jan Beulich wrote: >>>>> On 14.05.13 at 17:59, John Stultz wrote: >>> On 05/14/2013 12:57 AM, Jan Beulich wrote: >>>>>>> On 14.05.13 at 02:52, John Stultz >wrote: >>>>> Honestly, it seems a little strange to me. If you're running as >dom0, >>>>> why does HYPERVISOR_dom0_op() not cause the hypervisor to set the >cmos >>>>> its virtualizing? This seems to mess with the proper >virtualization >>>>> layering. >>>> Thy hypervisor tries to control as little system and peripheral >devices >>>> as possible, and the CMOS (including the clock) is among those not >>>> controlled by it, but by Dom0. >>> Huh. So what does calling HYPERVISOR_dom0_op do then? >> Here it merely tells the hypervisor that the wall clock changed (so >> it can propagate this on to DomU-s). > >Ok, I appreciate the explanation. Still waiting for acks on this one. > >thanks >-john Acked-by: Konrad Rzeszutek Wilk Or Reviewed-by. Or John if you would like I can carry this in my branch for Linus. Thought it might make sense to add the comment from Jan about the CMOS and the follow up explanation. -- Sent from my Android phone. Please excuse my brevity.