From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753312AbZK3Q2A (ORCPT ); Mon, 30 Nov 2009 11:28:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753187AbZK3Q17 (ORCPT ); Mon, 30 Nov 2009 11:27:59 -0500 Received: from e1.ny.us.ibm.com ([32.97.182.141]:56982 "EHLO e1.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752957AbZK3Q16 (ORCPT ); Mon, 30 Nov 2009 11:27:58 -0500 Subject: Re: kernel bug in kvm_intel From: Andrew Theurer Reply-To: habanero@linux.vnet.ibm.com To: Avi Kivity Cc: Tejun Heo , kvm@vger.kernel.org, Linux-kernel@vger.kernel.org In-Reply-To: <4B12895A.2010706@redhat.com> References: <4ACF9745.3050902@linux.vnet.ibm.com> <4AD16ACE.6040903@redhat.com> <1255372957.4883.49.camel@twinturbo.austin.ibm.com> <4AD4231F.6040608@redhat.com> <1255442640.4883.56.camel@twinturbo.austin.ibm.com> <4AD6061D.5070306@redhat.com> <1255637909.4883.129.camel@twinturbo.austin.ibm.com> <1256926052.4883.203.camel@twinturbo.austin.ibm.com> <4AEC5C24.9080506@redhat.com> <4AEC64FC.7070908@linux.vnet.ibm.com> <4AEC6699.6000202@redhat.com> <4AEC6821.7010801@redhat.com> <4AED5C3F.9050506@kernel.org> <4AED6100.6040804@redhat.com> <4AED66D0.20704@kernel.org> <4AED7178.2060906@redhat.com> <4B03BDCC.4080502@kernel.org> <4B0DDB5D.9030202@linux.vnet.ibm.com> <4B12895A.2010706@redhat.com> Content-Type: text/plain Date: Mon, 30 Nov 2009 10:27:44 -0600 Message-Id: <1259598464.29314.2.camel@twinturbo.austin.ibm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.26.3 (2.26.3-1.fc11) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2009-11-29 at 16:46 +0200, Avi Kivity wrote: > On 11/26/2009 03:35 AM, Andrew Theurer wrote: > > I just tried testing tip of kvm.git, but unfortunately I think I might > > be hitting a different problem, where processes run 100% in kernel > > mode. In my case, cpus 9 and 13 were stuck, running qemu processes. > > A stack backtrace for both cpus are below. FWIW, kernel.org > > 2.6.32-rc7 does not have this problem, or the original problem. > > I just posted a patch fixing this, titled "[PATCH tip:x86/entry] core: > fix user return notifier on fork()". > Thank you, Avi. I am running on this patch and am not seeing this problem anymore. I'll be testing for the previous issue next. -Andrew