From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Guest kernel hangs in smp kvm for older kernels prior to tsc sync cleanup Date: Wed, 19 Dec 2007 17:21:06 +0200 Message-ID: <476936E2.9010902@qumranet.com> References: <47680173.6060606@qumranet.com> <20071218221930.GA26109@elte.hu> <4768BB43.1000609@qumranet.com> <4768FE27.7020305@qumranet.com> <47690304.1090903@qumranet.com> <20071219140624.GF21282@elte.hu> <47693054.20501@qumranet.com> <20071219150938.GA15267@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel , linux-kernel To: Ingo Molnar Return-path: In-Reply-To: <20071219150938.GA15267-X9Un+BFzKDI@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Ingo Molnar wrote: > try this test perhaps in an SMP guest: > > http://people.redhat.com/mingo/time-warp-test/time-warp-test.c > > you can ignore TSC warps - but no GTOD or CLOCK warps should occur. > > On a broken guest kernel, I see gtod and clock warps. On a good guest kernel, I do not, presumably because the tsc clocksource is marked as unstable. I see tsc warps on both. 8 threads on 4 cpus. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- SF.Net email is sponsored by: Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace