From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: Guest hangs after some stress tests Date: Thu, 17 May 2012 23:05:49 +0300 Message-ID: <20120517200548.GA26391@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , Marcelo Tosatti , kvm@vger.kernel.org, Dave Jones To: Sasha Levin Return-path: Received: from mx1.redhat.com ([209.132.183.28]:46087 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932347Ab2EQUFx (ORCPT ); Thu, 17 May 2012 16:05:53 -0400 Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On Thu, May 17, 2012 at 09:49:08PM +0200, Sasha Levin wrote: > Hi all, > > I've observed a guest hang after putting a little stress testing on > it. It basically hangs in ~10 secs after running several trinity > instances inside a KVM tools guest. > And do you set hypervisor bit in KVM tool? > The hang is easy to describe and reproduce: > > 1. No userspace exits observed > 2. kvm_stat looks as follows (with all other fields at 0): > > kvm_entry 3631869 11819 > kvm_apic_accept_irq 1078688 11819 > kvm_exit 3631844 11819 > > I've bisected it down to: > > 9b72d3b07dd99ac8ab2b84de5004a295af460536 is the first bad commit > commit 9b72d3b07dd99ac8ab2b84de5004a295af460536 > Author: Gleb Natapov > Date: Mon Apr 30 14:45:49 2012 +0300 > > KVM guest: make kvm_para_available() check hypervisor bit reading cpuid leaf > > This cpuid range does not exist on real HW and Intel spec says that > "Information returned for highest basic information leaf" will be > returned. Not very well defined. > > Signed-off-by: Gleb Natapov > Signed-off-by: Avi Kivity -- Gleb.