From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?TWFyY2luIEdpYnXFgmE=?= Subject: Re: [Qemu-devel] [PATCH] kvmclock: Ensure time in migration never goes backward Date: Mon, 05 May 2014 19:46:41 +0200 Message-ID: <5367CE81.6030506@beyond.pl> References: <1399297882-3444-1-git-send-email-agraf@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org To: agraf@suse.de Return-path: Received: from mx.beyond.pl ([92.43.117.49]:39469 "EHLO mx.beyond.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751216AbaEER4v (ORCPT ); Mon, 5 May 2014 13:56:51 -0400 In-Reply-To: <1399297882-3444-1-git-send-email-agraf@suse.de> Sender: kvm-owner@vger.kernel.org List-ID: W dniu 2014-05-05 15:51, Alexander Graf pisze: > When we migrate we ask the kernel about its current belief on what the guest > time would be. However, I've seen cases where the kvmclock guest structure > indicates a time more recent than the kvm returned time. Hi, is it possible to have kvmclock jumping forward? Because I've reproducible case when at about 1 per 20 vm restores, VM freezes for couple of hours and then resumes with date few hundreds years ahead. Happens only with kvmclock. And this patch seems to fix very similar issue so maybe it's all the same bug. -- mg