From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Lieven Subject: Re: qemu-kvm-1.0.1 - unable to exit if vcpu is in infinite loop Date: Mon, 02 Jul 2012 10:12:10 +0200 Message-ID: <4FF157DA.2000805@dlhnet.de> References: <4FEC56B2.6050502@dlhnet.de> <4FEC5B5A.4060302@siemens.com> <4FEC7214.2020900@dlhnet.de> <4FEC76A8.6060100@siemens.com> <4FEC866F.5000402@dlhnet.de> <4FEC8722.7070301@redhat.com> <7C6F41F3-D0BC-4753-853D-E68B2AAAAADB@dlhnet.de> <4FF00825.7090606@redhat.com> <4FF14855.2040306@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Avi Kivity , "qemu-devel@nongnu.org" , "kvm@vger.kernel.org" To: Jan Kiszka Return-path: Received: from ssl.dlhnet.de ([91.198.192.8]:46283 "EHLO ssl.dlh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752248Ab2GBIMM (ORCPT ); Mon, 2 Jul 2012 04:12:12 -0400 In-Reply-To: <4FF14855.2040306@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: On 02.07.2012 09:05, Jan Kiszka wrote: > On 2012-07-01 21:18, Peter Lieven wrote: >> Am 01.07.2012 um 10:19 schrieb Avi Kivity: >> >>> On 06/28/2012 10:27 PM, Peter Lieven wrote: >>>> Am 28.06.2012 um 18:32 schrieb Avi Kivity: >>>> >>>>> On 06/28/2012 07:29 PM, Peter Lieven wrote: >>>>>>> Yes. A signal is sent, and KVM returns from the guest to userspace on >>>>>>> pending signals. >>>>>> is there a description available how this process exactly works? >>>>> The kernel part is in vcpu_enter_guest(), see the check for >>>>> signal_pending(). But this hasn't seen changes for quite a long while. >>>> Thank you, i will have a look. I noticed a few patches that where submitted >>>> during the last year, maybe one of them is related: >>>> >>>> Switch SIG_IPI to SIGUSR1 >>>> Fix signal handling of SIG_IPI when io-thread is enabled >>>> >>>> In the first commit there is mentioned a "32-on-64-bit Linux kernel bug" >>>> is there any reference to that? >>> >>> http://web.archiveorange.com/archive/v/1XS1vwGSFLyYygwTXg1K. Are you >>> running 32-on-64? >> I think the issue occurs when running a 32-bit guest on a 64-bit system. Afaik, the >> isolinux loader where is see the race is 32-bit altough it is a 64-bit ubuntu lts >> cd image. The second case where i have seen the race is on shutdown of a >> Windows 2000 Server which is also 32-bit. > "32-on-64" particularly means using a 32-bit QEMU[-kvm] binary on a > 64-bit host kernel. What does "file qemu-system-x86_64" report about yours? Its custom build on a 64-bit linux as 64-bit application. I will try to continue to find out today whats going wrong. Any help or hints appreciated ;-) Thanks, Peter > Jan >