From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932578AbcIBPkB (ORCPT ); Fri, 2 Sep 2016 11:40:01 -0400 Received: from mail-ve1eur01on0118.outbound.protection.outlook.com ([104.47.1.118]:10800 "EHLO EUR01-VE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932282AbcIBPjz (ORCPT ); Fri, 2 Sep 2016 11:39:55 -0400 X-Greylist: delayed 4072 seconds by postgrey-1.27 at vger.kernel.org; Fri, 02 Sep 2016 11:39:54 EDT Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=rkagan@virtuozzo.com; Date: Fri, 2 Sep 2016 18:24:40 +0300 From: Roman Kagan To: Paolo Bonzini CC: , , , , Subject: Re: [PATCH 3/4] KVM: x86: introduce get_kvmclock_ns Message-ID: <20160902152439.xraq7pmtryd2nkta@rkaganb.sw.ru> Mail-Followup-To: Roman Kagan , Paolo Bonzini , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, peterhornyack@google.com, rkrcmar@redhat.com, den@openvz.org References: <1472743575-123756-1-git-send-email-pbonzini@redhat.com> <1472743575-123756-4-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; 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This crystallizes the notion of > kvmclock as a thin veneer over a stable TSC, that the guest will > (hopefully) convert with NTP. In other words, kvmclock is *not* a > paravirtualized host-to-guest NTP. It might also be worth documenting this approach in a comment somewhere around pvclock_gtod_notify / update_pvclock_gtod or friends. And, if those could be simplified due to this change, it would be great, too. Roman.